DESC:AN APPARATUS AND METHOD FOR ANALYZING BIOLOGICAL SAMPLES

FIELD OF INVENTION
[01] The present invention, in general, relates to the field of medical diagnostic devices and more particularly, relates to an apparatus and method for analyzing biological samples, specifically for measuring Erythrocyte Sedimentation Rate (ESR).

BACKGROUND OF THE INVENTION

[02] Erythrocyte Sedimentation Rate (ESR) is a laboratory test that measures how quickly red blood cells (erythrocytes) settle to the bottom of a vertical tube of blood over a specific time period. The ESR test serves as an indicator of inflammation and is routinely used in medical practice to detect and monitor various inflammatory conditions. In the presence of inflammation, proteins like fibrinogen cause red blood cells to form stacks (rouleaux), which accelerate erythrocytes settling rate.
[03] The Westergren method is recognized as the standard reference method for measuring the ESR. The Westergren method involves placing anticoagulated blood in a 300mm vertical glass tube and measuring the distance that red blood cells fall over a one-hour period. While effective, the Westergren manual method has several limitations in modern clinical settings. The Westergren manual method requires trained personnel to perform the test, involves subjective visual interpretation of results, exposes healthcare workers to potential biohazards, and requires a full hour to complete, making it impractical for busy clinical environments.
[04] To address the limitations of the Westergren method, the patents US4848900A and US9733175B2 disclose an automated ESR analyzers. The majority of automated ESR systems require mixing blood with sodium citrate (3.8%) in specialized ESR tubes. While the citrate-based approach achieves approximately 99% accuracy compared to the Westergren method and yields results in about 30 minutes, the citrate-based approach still requires additional sample preparation steps. These additional steps increase workflow complexity and operational costs, as disclosed in US8211381B2.
[05] ESR analyzers capable of using blood directly from primary Ethylenediaminetetraacetic acid (EDTA) collection tubes have entered the market in recent developments. Certain direct-tube systems, as described in US6506606B1, employ an erythrocyte aggregation method rather than sedimentation, wherein blood is analyzed in capillary tubes or microfluidic channels. Although the aggregation-based method provides results in approximately 2 minutes, clinical validation studies demonstrate only 70-85% accuracy compared to the Westergren method. The accuracy deficiencies are particularly evident at higher ESR values where measurement precision is most clinically significant.
[06] Alternative direct-tube analyzers, as disclosed in patent publication WO2024/002939A1 and US11906413B2, maintain the sedimentation approach while enabling direct use of primary EDTA tubes. The sedimentation-based systems utilize optical detection with light emitters and receivers that move vertically along the tube to track the blood-plasma interface as sedimentation occurs. The optical detection systems achieve only 85-90% correlation with the Westergren method, with measurement discrepancies becoming more pronounced at elevated ESR levels above 50 mm/h.
[07] The reduced accuracy in existing direct-tube ESR analyzers stems from limitations in optical detection systems, as evidenced in devices described in EP0754945B1 and CN216695977U. Current ESR (Erythrocyte Sedimentation Rate) measurement devices utilize infrared emitters and receivers for detecting the blood-plasma interface during sedimentation analysis. These devices incorporate emitters with beam diameters typically exceeding 4 mm, which creates technical limitations in measurement precision. When such wide-beam infrared light is directed at a blood sample tube, the emitted light strikes the gradual transition zone between packed erythrocytes and plasma across a substantial vertical area. The wide beam diameter produces a gradient detection zone at the blood-plasma interface rather than identifying a precise boundary line. This technical limitation reduces measurement accuracy in ESR determination, where position detection precision of ±1mm is necessary for reliable results. The large beam diameter particularly affects measurement accuracy for blood samples with very low ESR values (less than 5 millimeters per hour, where millimeters per hour represents the distance erythrocytes fall within a standardized tube during a one-hour period) and high ESR values (greater than 50 millimeters per hour). In low ESR samples, minimal sedimentation occurs, making precise detection of small changes critical. In high ESR samples, rapid sedimentation produces steeper gradients requiring accurate interface tracking. The imprecise interface detection capability of current optical systems represents a fundamental constraint that limits correlation with the Westergren method to approximately 90% at maximum.
[08] Therefore, there is a need in the art to provide an apparatus and method for analyzing biological samples with greater accuracy and in less time, particularly by improving the precision of optical detection systems used in ESR measurement.

SUMMARY OF THE INVENTION
[09] This summary is provided to introduce the concepts related to an apparatus and method for analyzing biological samples. The concepts are further described in the detailed description. This summary is not intended to identify essential features of the claimed subject matter, nor is it intended to be used in determining or limiting the scope of the present invention.
[010] In an exemplary embodiment, an apparatus for analyzing biological samples is described. The apparatus comprises a housing, a tube receiving unit, an optical module, a drive unit, a set of optical elements and a control unit. The tube receiving unit is attached to the housing. The tube receiving unit is configured to receive at least one tube. The at least one tube contains biological samples. The optical module is housed inside the housing, wherein the optical module is operatively coupled with the tube receiving unit. The optical module comprises at least one light emitting assembly and at least one light receiving assembly. The at least one light emitting assembly is configured to emit light. The at least one light receiving assembly is configured to receive the emitted light. The drive unit is configured to move the optical module relative to the at least one tube. The set of optical elements is positioned in a light path between the light emitting assembly and the light receiving assembly. The set of optical elements focus the emitted light towards the light receiving assembly. The biological samples obstruct the light path. The light receiving assembly detects the intensity of light received at the light receiving assembly. The control unit measures changes in the biological samples in the at least one tube based on the intensity of light received at the light receiving assembly.
[011] In some embodiments, the biological samples comprise blood samples. The apparatus is configured to measure the erythrocyte sedimentation rate (ESR) in the blood samples by detecting changes in a blood-plasma interface over time.
[012] In some embodiments, the tube receiving unit comprises a first plurality of slots. Each slot from the first plurality of slots receives the at least one tube. The optical module comprises an optical module housing having a second plurality of slots. The second plurality of slots are coaxial with the first plurality of slots to receive and align the tube receiving unit. The at least one light emitting assembly and the at least one light receiving assembly are housed inside the optical module housing.
[013] In some embodiments, the at least one light emitting assembly comprises a first printed circuit board having at least one Light Emitting Diode (LED) emitter mounted thereon. The set of optical elements includes a first optical element and a second optical element. The first optical element is positioned between the at least one tube and a first spacer to direct light rays from the LED emitter towards the at least one tube. The first spacer is positioned between the first printed circuit board and the first optical element to prevent light leakage.
[014] In some embodiments, the at least one light receiving assembly comprises a second printed circuit board having at least one receiver mounted thereon. The second optical element from the set of optical elements is positioned between the at least one tube and a second spacer to direct transmitted light from the at least one tube towards the at least one receiver. The second spacer is positioned between the second printed circuit board and the second optical element to prevent light leakage.
[015] In some embodiments, the drive unit comprises a stepper motor, a lead screw, a coupler, at least one guide rod, and a position detector. The stepper motor has an output shaft. The lead screw is attached to the output shaft for converting rotational motion to linear motion to enable vertical movement of the optical module. The optical module is guided along the at least one guide rod. The position detector is operatively coupled with the optical module to monitor and control a vertical movement of the optical module during measurement.
[016] In some embodiments, the set of optical elements comprises lens, or an aperture configured in one of circular, rectangular, triangular, or polygonal shape. The optical elements are configured to control the light path between the light emitting assembly and the light receiving assembly.
[017] In some embodiments, the control unit is configured to operate the at least one LED emitter in a pulse mode at a predetermined frequency and at a predetermined intensity. The pulse mode operates at the predetermined frequency between 2 Hz to 500 Hz.
[018] In some embodiments, the at least one receiver comprises a photodiode. The at least one receiver is configured to detect transmitted light at predetermined intensity. The photodiode generates signals. The control unit processes the signals for measuring the changes in the biological samples.
[019] In some embodiments, the first printed circuit board and the second printed circuit board are vertically oriented within the optical module.
[020] In some embodiments, the tube receiving unit comprises an adjustable holder. The adjustable holder is configured to accommodate the at least one tube of varying dimensions including pediatric tube.
[021] In some embodiments, the apparatus further comprises a display. The display is configured to present measurement results and a set of operational parameters to a user.
[022] In some embodiments, the control unit directs the drive unit to move the optical module at predetermined time intervals to generate a measurement curve. The measurement curve represents the erythrocyte sedimentation rate (ESR) over time.
[023] In some embodiments, the apparatus comprises a quality control element having predetermined height markers. The quality control element is configured to validate measurement accuracy of the apparatus. The quality control element includes at least three predefined height levels corresponding to different blood interface levels.
[024] In another exemplary embodiment, a method for analyzing biological samples is described. In the first step, the method comprises receiving at least one tube containing biological samples in a tube receiving unit. In the second step, the method includes emitting light from a light emitting assembly of an optical module. In the third step, the method includes receiving the emitted light at a light receiving assembly of the optical module. In the fourth step, the method includes positioning a set of optical elements in a light path between the light emitting assembly and the light receiving assembly, the set of optical elements focusing the emitted light towards the light receiving assembly such that the biological samples obstruct the light path and enabling the light receiving assembly for detecting intensity of light received at the light receiving assembly. In the fifth step, the method includes moving the optical module relative to the at least one tube using a drive unit. In the last step, the method includes measuring, by a control unit of the apparatus, changes in the biological samples based on the detected light intensity at different positions of the optical module relative to the at least one tube.
[025] The foregoing general description of the illustrative embodiments and the following detailed description thereof are merely exemplary aspects of the teachings of this disclosure and are not restrictive.

BRIEF DESCRIPTION OF DRAWINGS
[026] The detailed description is described with reference to the accompanying figures. The same numbers are used throughout the drawings to refer like features and components.
[027] FIG. 1 illustrates a perspective view of an apparatus for analyzing biological samples, in accordance with one embodiment of the present invention;
[028] FIG. 2 illustrates a perspective view of an operational assembly, in accordance with one embodiment of the present invention;
[029] FIG. 3 illustrates an exploded view of an optical module, in accordance with one embodiment of the present invention;
[030] FIG. 4 illustrates sectional view of the apparatus depicting the tube holder support and a tube holder receiver, in accordance with one embodiment of the present invention;
[031] FIG. 5 illustrates a top view of the optical module, in accordance with one embodiment of the present invention;
[032] FIG. 6 illustrates sectional view of the operational assembly with retracted tube receiver unit, in accordance with one exemplary embodiment of the present invention;
[033] FIG. 7 illustrates another sectional view of the operational assembly with the optical module inside the tube receiving unit, in accordance with one exemplary embodiment of the present invention;
[034] FIG. 8 illustrates another sectional view of the operational assembly with Pediatric tube, in accordance with one exemplary embodiment of the present invention;
[035] FIG. 9 illustrates the front view of the at least one tube with a quality control element, in accordance with one embodiment of the present invention;
[036] FIG. 10 illustrates, in a flowchart, operations for analyzing biological samples, in accordance with one embodiment of the present invention;
[037] FIG. 11A illustrates a graph representing the comparison with the Westergren method with rectangular aperture, in accordance with one embodiment of the present invention;
[038] FIG. 11B illustrates a graph representing the comparison with the Westergren method with circular aperture, in accordance with one embodiment of the present invention;
[039] FIG. 12 illustrates a graph representing the comparison with the Westergren method with circular aperture, in accordance with one embodiment of the present invention; and
[040] FIG. 13 illustrates graph representing the representative sedimentation curves for blood samples with high and low ESR values, in accordance with one embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION
[041] The following detailed description is susceptible to various modifications and alternative forms, specific embodiments thereof will be described in detail and shown by way of example. It should be understood, however, that there is no intent to limit example embodiments of the present invention to the particular forms disclosed. Conversely, example embodiments are to cover all modifications, equivalents, and alternatives falling within the scope of the invention.
[042] It should be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of the present invention.
[043] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should be further understood that the terms “comprises,” “comprising,” “includes,” “including,” and/or “having” specify the presence of stated features, integers, steps, operations, elements, and/or components when used herein, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
[044] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. It should be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and are not to be interpreted in an idealized or overly formal sense unless expressly so defined herein.
[045] The present invention relates to an apparatus for analyzing biological samples. The apparatus comprises a housing, a tube receiving unit, an optical module, a drive unit, a set of optical elements and a control unit. The tube receiving unit is attached to the housing. The tube receiving unit is configured to receive at least one tube. The at least one tube contains biological samples. The optical module is housed inside the housing, wherein the optical module is operatively coupled with the tube receiving unit. The optical module comprises at least one light emitting assembly and at least one light receiving assembly. The at least one light emitting assembly is configured to emit light. The at least one light receiving assembly is configured to receive the emitted light. The drive unit is configured to move the optical module relative to the at least one tube. The set of optical elements is positioned in a light path between the light emitting assembly and the light receiving assembly. The set of optical elements focus the emitted light towards the light receiving assembly. The biological samples obstruct the light path. The light receiving assembly detects the intensity of light received at the light receiving assembly. The control unit measures changes in the biological samples in the at least one tube based on the intensity of light received at the light receiving assembly.
[046] The apparatus is now explained in detail with reference to FIG. 1 to FIG. 13.
[047] FIG. 1 illustrates a perspective view of an apparatus 10 for analyzing biological samples, in accordance with one embodiment of the present invention. The apparatus 10 comprises a housing 9 and a display 14 mounted on the housing 9. The housing 9 comprises a tube receiving unit 42. The tube receiving unit 42 comprises slots (42a, 42b, 42c,…) for holding at least one tube 20 (depicted in FIG. 2) at a fixed elevation with respect to the ground. Further, the housing 9 encloses an operational assembly 12 (depicted in FIG. 2). The operational assembly 12 is configured for analyzing the biological samples collected in the at least one tube 20.
[048] In an embodiment, the at least one tube 20 may be blood collection vacuum tubes made of polyethylene terephthalate (PET), polypropylene or glass containing anticoagulants including ethylenediaminetetraacetic acid (EDTA), sodium or lithium heparin, sodium citrate, and sodium oxalate/sodium fluoride. The at least one tube 20 includes standardized dimensions compatible with the tube receiving unit 42, typically measuring 13 x 75 mm for standard tubes and proportionally smaller dimensions for pediatric tubes. The at least one tube 20 materials include PET, polypropylene, or glass, chosen for optimal light transmission properties in the 750-1100 nm wavelength range. The at least one tube 20 features a cap that maintains sample integrity and prevents contamination during handling and measurement. The at least one tube 20 accommodates blood volumes ranging from 0.5 mL for pediatric samples to 4 mL for standard adult samples, enabling ESR analysis across diverse clinical requirements.
[049] In an embodiment, the biological samples are whole blood samples collected from a patient. The operational assembly 12 is configured for measuring Erythrocyte Sedimentation Rate (ESR) in the blood samples. The ESR corresponds to the fall or sedimentation of erythrocytes in a blood column over a period of time, measured in millimeters per hour. The ESR serves as a non-specific test used to measure inflammation and other diseases. An increase in ESR indicates underlying pathological processes where certain protein concentrations lead to faster sedimentation of erythrocytes. Once the ESR is measured, the display 14 of the apparatus 10 is configured to display ESR measurements. The display 14 is also configured to present measurement results and a set of operational parameters for a user. The apparatus 10 enables clinicians to use ESR measurements for screening inflammation, infection and monitoring the progression of disease conditions such as cancer, rheumatoid arthritis, tuberculosis, and other inflammatory diseases.
[050] In another embodiment, the apparatus 10 further comprises connection ports (not shown) configured to connect with one or more extension modules. These extension modules expand the sample processing capacity of the apparatus 10, enabling simultaneous analysis of additional tubes. When connected with the one or more extension modules, the apparatus 10 functions as a modular console, capable of controlling multiple extension modules to increase throughput from 10 samples to 30 or more samples per batch, with scalability to accommodate up to 100 blood samples, thereby enabling a throughput of 30-300 samples per hour for ESR analysis.
[051] The process of capturing the ESR measurements by the operational assembly 12 of the apparatus 10 is elaborated with reference to FIG. 2-7. The operational assembly 12 is now described in detail to illustrate the arrangement and interaction of its key functional components with reference to FIG. 2.
[052] Now referring to FIG. 2, a perspective view of an operational assembly 12 is illustrated in accordance with one embodiment of the present invention. The operational assembly 12 comprises an optical module 16, a drive unit 17, a set of optical elements 22a, 22b (as shown in FIG. 3) and a control unit 46. As stated in the description of FIG. 1, the tube receiving unit 42 is attached to the housing 9. The tube receiving unit 42 comprises a first plurality of slots (42a, 42b, 42c…). At least one slot 42a, of the first plurality of slots (42a, 42b, 42c…) is configured to receive the at least one tube 20 containing the biological samples. It must be noted that multiple tubes may be inserted in the first plurality of slots (42a, 42b, 42c…) and tested parallelly by the operational assembly 12. For this purpose, the optical module 16 is enabled with a second plurality of slots (18a, 18b, 18c,…). Each slot from the second plurality of slots (18a, 18b, 18c,…) is coaxial with a corresponding slot from the plurality of slots (42a, 42b, 42c…). While the first plurality of slots (42a, 42b, 42c…) are stationary, the second plurality of slots (18a, 18b, 18c,…) move vertically along with the optical module 16 as the optical module 16 is configured to move vertically with respect to the tube receiving unit 42. The optical module 16 comprises at least one light emitting assembly 16a (depicted in FIG. 3) and at least one light receiving assembly 16b (depicted in FIG. 3). The at least one light emitting assembly 16a is configured to emit light. The at least one light receiving assembly 16b is configured to receive the emitted light. It must be noted that each slot from the second plurality of slots (18a, 18b, 18c,…) is enabled with an independent light emitter 40 that is part of at least one light emitting assembly 16a and light receiver 36 that is part of at least one light receiving assembly 16b for independent ESR analysis of biological sample place in the respective slot of the second plurality of slots (18a, 18b, 18c,…).
[053] The drive unit 17 is configured to move the optical module 16 in vertically along the z-axis where the at least one tube 20 remains stationary in a fixed position within the tube receiving unit 42. The vertical movement of the optical module 16 is to track the progressive sedimentation of erythrocytes at regular time intervals. By scanning the blood-plasma interface at defined positions over a 15–30-minute measurement period, the apparatus 10 captures the dynamic sedimentation profile, which is essential for accurate ESR determination. This automated scanning mechanism eliminates the variability associated with manual measurements while reducing the overall analysis time compared to conventional methods. The drive unit 17 comprises a stepper motor 32 operatively coupled to a lead screw 26 through a coupler 34, at least one guide rod 28, and a position detector 44. The lead screw 26 is attached to an output shaft 32a of the stepper motor 32 for converting rotational motion to linear motion to enable vertical movement of the optical module 16. The optical module 16 is guided along at least one guide rod 28. The position detector 44 is operatively coupled with the optical module 16 to monitor and control a vertical movement of the optical module 16 during measurement.
[054] The stepper motor 32 with gear may divide a full rotation into a number of equal steps, enabling precise position control without any feedback mechanism. The stepper motor 32 may typically operate at 200-25600 steps per revolution to provide precise control over the vertical movement.
[055] The lead screw 26 may have a pitch of 1-2mm per revolution to achieve precise vertical positioning. The coupler 34 mechanically connects the output shaft 32a to the lead screw 26 while compensating for minor misalignments.
[056] The at least one guide rod 28 is positioned parallel to the lead screw 26. The guide rod 28 provides smooth, low-friction guidance for the optical module 16 during vertical movement. The guide rod 28 prevents rotation of the optical module 16 around the lead screw 26 axis while maintaining precise linear motion.
[057] The position detector 44 is operatively coupled with the optical module 16 to monitor and control the vertical movement of the optical module 16 during measurement. The position detector 44 comprises optical or magnetic sensors that may provide feedback about the position of optical module 16. The position detector 44 enables height measurements with accuracy better than +/- 0.01mm, also used to limit movement, ensuring it does not exceed the predefined upper and lower levels, which may be essential for precise ESR determination.
[058] The set of optical elements 22a, 22b is positioned in a light path between the light emitting assembly 16a and the light receiving assembly 16b. The set of optical elements 22a, 22b focus the emitted light towards the light receiving assembly 16b. The biological samples obstruct the light path. The light receiving assembly 16b detects intensity of light received at the light receiving assembly 16b. The control unit 46 measures changes in the biological samples in the at least one tube 20 based on the intensity of light received at the light receiving assembly 16b. The control unit 46 comprises a microcontroller (not shown) and associated memory (not shown) that executes programmed algorithms to process the intensity data from the light receiving assembly 16b at different vertical positions. The control unit 46 analyzes the detected light intensity patterns over time to identify the precise location of the blood-plasma interface as the erythrocyte’s sediment. Furthermore, the control unit 46 applies a mathematical transformation to convert the measured sedimentation rate into standardized ESR values that correlate with clinical reference ranges, while also managing the timing and sequence of the vertical scanning operations. The drive unit 17 operates in a controlled manner where the stepper motor 32 may rotate at predefined intervals, typically every 1-2 minutes. This controlled movement enable the optical module 16 to scan the blood-plasma interface at regular intervals over a 15–30-minute measurement period. The scanning generates data points for plotting sedimentation curves that represents the rate of erythrocyte settling in the blood sample.
[059] The optical module 16 enables measurement of changes in biological samples. To better understand the detailed arrangement and functionality of the optical module 16, reference is now made to FIG. 3, which provides an exploded view of the components in the optical module 16. This exploded view illustrates how the various components within the optical module 16 are spatially arranged to create the optical measurement system essential for ESR analysis.
[060] Now referring to FIG. 3 illustrates an exploded view of the optical module 16 in accordance with one embodiment of the present invention. The at least one light emitting assembly 16a and the at least one light receiving assembly 16b are housed inside the optical module housing 19. The at least one light emitting assembly 16a is configured to emit light. The at least one light receiving assembly 16b is configured to receive the emitted light. The tube receiving unit 42 comprises a first plurality of slots (42a, 42b, 42c…). Each slot from the first plurality of slots (42a, 42b, 42c…) receives the at least one tube 20. The optical module 16 comprises an optical module housing 19 having a second plurality of slots (18a, 18b, 18c…). The second plurality of slots (18a, 18b, 18c…) are coaxial with the first plurality of slots (42a, 42b, 42c…) to receive and align the tube receiving unit 42. The light emitting assembly 16a and a light receiving assembly 16b are positioned on opposite sides of the second plurality of slots (18a, 18b, 18c…) .
[061] The light emitting assembly 16a comprises a first printed circuit board 24 with at least one Light Emitting Diode (LED) emitter 40 mounted thereon. The first printed circuit board 24 is vertically oriented within the optical module 16. The LED emitter 40 operates in infrared spectrum, specifically chosen for its ability to penetrate through standard blood collection tubes made of materials like PET, polypropylene, or glass. The LED emitter 40 operates in pulse mode with frequency between 2 Hz to 500 Hz, typically optimized at 20 Hz. This pulsed operation, similar to a strobe light, generates concentrated bursts of illumination with wavelengths from 750-1100 nm and radial intensity between 1200 to 2100 mW/sr at 200 mA. Such specifications enable reliable light transmission through various blood collection tubes including those with paper labels containing patient information.
[062] The set of optical elements 22a, 22b comprises a first optical element 22a and a second optical element 22b. The first optical element 22a from the set of optical elements 22a, 22b is positioned between the at least one tube 20 and a first spacer 38a. The first optical element 22a directs light rays from the LED emitter 40 towards the at least one tube 20 position. The first spacer 38a, fabricated from light-absorbing material, is positioned between the first printed circuit board 24 and the first optical element 22a, creating a light-sealed chamber.
[063] The light receiving assembly 16b includes a second printed circuit board 30 with at least one receiver 36 mounted thereon. The at least one receiver 36 is a photodiode configured to detect transmitted light at predetermined intensity. The control unit 46 processes signals from the photodiode for measuring the changes in the biological samples.
[064] The second printed circuit board 30 is also vertically oriented. The second optical element 22b from the set of optical elements is positioned between the at least one tube 20 and a second spacer 38b. The second optical element 22b directs transmitted light from the tube position towards the receiver 36. The second spacer 38b, similar to the first spacer, creates a light-sealed chamber. The photodiode receiver 36 can detect light intensity as low as 0.5 mW/cm², essential for measuring subtle changes in blood-plasma interface position.
[065] In an embodiment, the vertical orientation of both printed circuit boards 24, 30 represents a significant improvement over traditional bent LED/photodiode configurations found in existing ESR analyzers. This arrangement, similar to precision optical benches used in laboratory instruments, maintains consistent alignment throughout the measurement process. Clinical validation studies have shown that this optical configuration achieves correlation exceeding 95% with the Westergren method, the internationally recognized standard for ESR measurement. The physical arrangement of the optical elements 22a, 22b within the optical module 16 is critical for precise measurement of the blood-plasma interface.
[066] The set of optical elements 22a, 22b control the light path between the light emitting assembly and light receiving assembly. Each optical element from the set of optical elements 22a, 22b comprises an aperture configured in one of circular, rectangular, triangular, or polygonal shape. In another embodiment the set of optical elements 22a, 22b are lenses. In one implementation when the aperture is circular the diameter of circular apertures ranges between 0.1 mm to 2 mm. While rectangular apertures have width between 0.1 mm to 2 mm and length between 0.5 mm to 4 mm. The triangular and polygonal apertures maintain similar dimensional constraints with openings not exceeding 4 mm² total area.
[067] The different aperture shapes provide specific functions in measurement. Circular apertures produce uniform light distribution for ESR measurements in the range of 1-140 mm/hr. The rectangular apertures detect the blood-plasma interface through their extended dimension, supporting measurements of ESR values above 100 mm/hr. Triangular apertures focus light intensity for ESR measurements below 20 mm/hr. Polygonal apertures combine these capabilities for operation across the measurement range.
[068] The aperture thickness measures between 0.1 mm to 1 mm. The thinner apertures allow wider light dispersion while thicker apertures produce directed light beams. The apertures are formed through electric drilling, laser cutting, photoetching, or injection molding of plastic. The aperture materials include anodized aluminum, blackened stainless steel, or polymers that absorb light to prevent internal reflections.
[069] In one implementation, the apertures utilize multiple layers of different diameters to create a tapered light path that reduces light scattering at edges. In another implementation, micro-lenses integrate with the apertures to direct the light beam. The aperture structure includes mounting points for optical filters to select specific light wavelengths.
[070] The aperture dimensions constrain the LED light beam spread angle. This focused beam detects the blood-plasma interface with measurement variation within ±1 mm. When light transmits through the blood sample, the defined beam generates a clear signal change at the boundary between settled red blood cells and plasma, enabling accurate height measurements for ESR calculation.
[071] To further illustrate the spatial relationship between the drive unit 17, the optical module 16 and the at least one tube 20, reference is now made to FIG. 4. This sectional view provides a clear representation of how light travels through the system and interacts with the biological sample during ESR measurement.
[072] FIG. 4 illustrates a sectional view of the operational assembly 12 and the optical module 16 showing the arrangement of optical elements and at least one tube 20 positioning in accordance with an embodiment of the present invention. As represented in FIG. 4, the light emitting assembly 16a of the optical module 16 is positioned on one side of the at least one tube 20 and a light receiving assembly 16b is positioned on the opposite side of the at least one tube 20.
[073] Further, the drive unit 17 is configured to move the optical module 16 vertically along the z-axis where the at least one tube 20 remains stationary in a fixed position within the tube receiving unit 42. During the vertical movement of the optical module 16, the light emitting assembly 16a continuously emits light which is captured by the light receiving assembly 16b to track the progressive sedimentation of erythrocytes at regular time intervals by scanning the blood-plasma interface at defined positions over a 15–30-minute measurement period.
[074] The drive unit 17 comprises a stepper motor 32 operatively coupled to a lead screw 26 through a coupler 34, at least one guide rod 28, and a position detector 44. The stepper motor 32 is electrically connected to the control unit, which provides precise timing signals to control the motor's rotational speed and position. The lead screw 26 is attached to an output shaft 32a of the stepper motor 32 for converting rotational motion to linear motion to enable vertical movement of the optical module 16. The lead screw 26 interfaces with a threaded component 23 that translates the rotational motion into linear movement. The motion of the lead screw 26 is transfer to the optical module 16 via a connecting rod 21. The optical module 16 is guided along at least one guide rod 28. The position detector 44 is operatively coupled with the optical module 16 to monitor and control a vertical movement of the optical module 16 during measurement. In one embodiment, the control unit 46 directs the stepper motor 32 to move at predetermined intervals, typically every 1-2 minutes, to scan the blood-plasma interface position at regular time points during the sedimentation process. The apparatus 10 captures the dynamic sedimentation profile, which is essential for accurate ESR determination.
[075] On the right side of the FIG. 4, the at least one tube 20 is shown in its vertical orientation with a cap 20a at the top. The at least one tube 20 is positioned between the light emitting assembly 16a on the right side and the light receiving assembly 16b on the left side. The light emitting assembly 16a includes a first printed circuit board 24 with connection ports 24a mounted at the bottom. These connection ports 24a establish electrical communication between the first printed circuit board 24 and a control unit 46, enabling precise control of the LED emitter 40. The LED emitter 40 is positioned on the right side, with the first optical element 22a directing light toward the at least one tube 20.
[076] On the opposite side, the light receiving assembly 16b includes a second printed circuit board 30 with connection ports 30a at the bottom. These connection ports 30a link the second printed circuit board 30 to the control unit 46, facilitating the transmission of signal data from the receiver 36 for processing. The receiver 36 is positioned to detect light that passes through the tube 20, with the second optical element 22b focusing the transmitted light onto the receiver 36 for precise measurements.
[077] The light emitting assembly includes an LED emitter 40 and a first optical element 22a. The first optical element 22a controls the light beam directed toward the at least tube 20. The light receiving assembly includes a receiver 36 and a second optical element 22b. The second optical element 22b controls the light transmitted through the at least one tube 20 before reaching the receiver 36.
[078] The tube 20 is positioned between the optical elements 22a, 22b in a vertical orientation. The optical elements 22a, 22b create a defined light path through the tube 20, enabling accurate measurement of the blood-plasma interface position as erythrocytes settle under gravity. The optical module 16 is now further described with reference to FIG. 5.
[079] Now referring to FIG. 5 illustrates a top view of the optical module 16 showing the linear arrangement of multiple measurement channels in accordance with one embodiment of the present invention. The optical module 16 incorporates a second plurality of slots (18a, 18b, 18c…)in series configuration designed to accommodate at least one tube 20 for simultaneous ESR analysis.
[080] For each measurement channel, the optical module 16 arranges components in a symmetrical configuration. The first spacer 38a and second spacer 38b are positioned on opposite sides of each slot of the second plurality of slots (18a, 18b, 18c…). Between the first spacer 38a and each tube position, the first optical element 22a directs the light from LED emitter 40. Between the second spacer 38b and each tube position, a second optical element 22b directs light to the receiver 36.
[081] The optical module 16 implements a linear array configuration where multiple sets of LED emitters 40 and receivers 36 operate in parallel. Each measurement channel maintains identical spacing and alignment between components. The LED emitters 40 mount on one side while the receivers 36 align directly opposite, creating parallel optical paths through each tube position.
[082] This multi-channel design enables concurrent analysis of multiple blood samples, with each channel maintaining independent light paths isolated by the spacers 38a, 38b. The linear arrangement facilitates standardized measurement conditions across all samples while optimizing throughput capacity of the apparatus.
[083] FIG. 6 and FIG. 7 illustrates a sectional view of the operational assembly 12 with a retracted and engaged tube receiving unit 42 with an optical module 16 in accordance with one embodiment of the present invention. As represented in FIG. 6 the drive unit 17 is configured to move the optical module 16 in vertical direction. The stepper motor 32 of the drive unit 17 is operatively coupled to the lead screw 26 through a coupler 34, at least one guide rod 28, and the position detector 44.
[084] The tube receiving unit 42 comprises of a first plurality of slots (42a, 42b, 42c…) to accommodate at least one tube 20. The at least one tube 20 comprises a cap 20a. The optical module 16 comprises at least one light emitting assembly 16a and at least one light receiving assembly 16b. The at least one light emitting assembly 16a and the at least one light receiving assembly 16b are housed inside the optical module housing 19. The at least one light emitting assembly 16a is configured to emit light. The at least one light receiving assembly 16b is configured to receive the emitted light. Further, the optical module 16 comprises an optical module housing 19 having a second plurality of slots (18a, 18b, 18c…) . Each slot from the second plurality of slots (18a, 18b, 18c,…) is coaxial with a corresponding slot from the plurality of slots (42a, 42b, 42c…) to receive and align the tube receiving unit 42. In the illustrated configuration, the tube receiving unit 42 is shown in a retracted position, demonstrating the accessibility for loading or unloading the at least one tube 20 at any position. In operation, the drive unit 17 is configured to move the optical module 16 while the tube receiving unit 42 with at least one tube 20 remains stationary.
[085] The linear arrangement of the at least one tube 20 positions in the tube receiving unit 42 enables both random access and batch processing capabilities. Each tube position operates independently, allowing ESR analysis to start as soon as the at least one tube 20 is loaded without waiting for other positions to be filled. The spacing between tube positions matches the optical element spacing in the optical module 16, ensuring consistent measurement conditions for each sample. Each tube 20 position maintains an independent alignment with its corresponding optical path when the tube receiving unit 42 engages with the optical module 16, allowing simultaneous or individual sample processing based on laboratory workflow requirements.
[086] FIG. 7 illustrates a sectional view of the operational assembly 12 showing the tube receiving unit 42 engaged with the optical module housing 19. The operational assembly 12 demonstrates the measurement configuration where the tube receiving unit 42 aligns with the optical module 16 for ESR analysis.
[087] FIG. 8 illustrates a sectional view of the operational assembly 12 configured with a pediatric tube 25 in accordance with an embodiment of the present invention. In one implementation an apparatus 10 is enabled to handle the pediatric tube 25. The pediatric tube 25 comprises cap 25a. The operational assembly 12 demonstrates the versatility of the tube receiving unit 42 to accommodate different tube sizes. The tube receiving unit 42 comprises an adjustable holder 25b. The adjustable holder 25b configured to accommodate the at least one tube 20 of varying dimensions including the pediatric tube 25.
[088] The tube receiving unit 42 accepts the pediatric tube 25, which has smaller dimensions compared to standard tubes. The pediatric tube 25 typically contains reduced blood volume suitable for pediatric patients, geriatric patients, or cases where limited sample volume is available. The pediatric tube 25 with its cap 25a, which includes component 25b, is securely held within the tube receiving unit 42. The optical module 16 maintains consistent measurement capability regardless of tube size. When the tube receiving unit 42 engages with the optical module 16, the optical paths align correctly with the pediatric tube 25. The vertical scanning mechanism, driven by the stepper motor at the top, operates with the same precision for pediatric tubes as for standard tubes.
[089] FIG. 9 illustrates a quality control element 100 for validating measurement accuracy of the apparatus in accordance with an embodiment of the present invention. The quality control element 100 includes three predefined height levels corresponding to different blood interface levels - level 1 (102), level 2 (104), and level 3 (106).
[090] The level 1 (102) is set at 9 mm height, level 2 (104) at 24 mm height, and level 3 (106) at 39 mm height. These heights simulate different ESR values commonly encountered in clinical settings. The quality control element 100 is fabricated through 3D-printing or injection molding processes to ensure dimensional accuracy.
[091] Each height level in the quality control element 100 corresponds to specific interface positions that the apparatus must detect within ±1 mm tolerance. When inserted into the apparatus, the optical module scans these predefined heights. The apparatus validates its mechanical and optical systems by comparing measured heights against these known reference values. A successful quality control check confirms the apparatus can detect interface positions accurately across low, medium, and high ESR ranges.
[092] If measured values match the predefined heights within tolerance limits, the apparatus passes quality control validation. Any deviation beyond ±1 mm indicates potential mechanical or optical issues requiring attention. This internal quality control process ensures reliable ESR measurements across the operating range of 1-140 mm/hr. After describing the quality control element 100 and its validation capabilities, it is essential to understand the complete methodological process through which the apparatus 10 performs biological sample analysis. The apparatus 10 follows a systematic analytical procedure that involves multiple coordinated steps from sample loading to final result generation. To illustrate this comprehensive workflow, reference is now made to FIG. 10, which presents a structured flowchart of the analysis process.
[093] FIG. 10 illustrates a flowchart 200 for analyzing biological samples, specifically measuring erythrocyte sedimentation rate (ESR) in blood samples, in accordance with an embodiment of the present invention.
[094] Step 201 involves receiving at least one tube 20 containing biological samples in a tube receiving unit 42. A healthcare professional collects blood from a patient using a syringe or venipuncture kit and transfers it into the at least one tube 20. The at least one tube 20 contains anticoagulants like ethylenediaminetetraacetic acid (EDTA), sodium heparin, lithium heparin, sodium citrate, or sodium oxalate/sodium fluoride pre-added by the manufacturer. The at least one tube 20 material comprises polyethylene terephthalate (PET), polypropylene, or glass, selected for optimal light transmission properties.
[095] Step 202 involves allowing the biological samples to settle undisturbed in the at least one tube 20 for a specific duration. During this period, when the biological samples comprise blood samples, the erythrocytes begin sedimentation under gravity, creating a distinguishable interface between settled red blood cells and plasma.
[096] Step 203 involves emitting light from a light emitting assembly 16a of an optical module 16 and receiving the emitted light at a light receiving assembly 16b of the optical module 16. The light emitting assembly 16a includes a Light Emitting Diode (LED) emitter 40 that projects light through a first optical element 22a, through the biological samples, and through a second optical element 22b to the light receiving assembly 16b. The light receiving assembly 16b detects intensity of light received at the light receiving assembly 16b, which varies as the biological samples change, with different light transmission properties depending on the sample composition.
[097] Step 204 involves positioning a set of optical elements 22a, 22b in a light path between the light emitting assembly 16a and the light receiving assembly 16b. The set of optical elements 22a, 22b focus the emitted light towards the light receiving assembly 16b such that the biological samples obstruct the light path, enabling the light receiving assembly 16b to detect intensity of light received. The control unit 46 operates the LED emitter 40 in pulse mode at a predetermined frequency between 2 Hz to 500 Hz, typically optimized at 20 Hz, and at a predetermined intensity. The pulse mode operation generates higher intensity light bursts, compensating for reduced light transmission through the apertures in optical elements 22a, 22b.
[098] Step 205 involves moving the optical module 16 relative to the at least one tube 20 using a drive unit 17. The drive unit 17, comprising a stepper motor 32, a lead screw 26, at least one guide rod 28, and a position detector 44, controls vertical movement of the optical module 16 relative to the at least one tube 20. The optical module 16 performs multiple sequential vertical movements to scan the entire height of the biological sample at different positions relative to the at least one tube 20 at predetermined time intervals, typically every 1-2 minutes over a 15-30 minute period. Each vertical movement generates a data point corresponding to the blood-plasma interface position at that specific time point. The collection of these sequential position measurements enables the control unit 46 to plot them as a time-series graph, creating a dynamic sedimentation curve that captures the progressive settling of erythrocytes over the measurement period.
[099] Step 206 involves measuring, by a control unit 46 of the apparatus 10, changes in the biological samples based on the detected light intensity at different positions of the optical module 16 relative to the at least one tube 20. The tube receiving unit 42 comprises an adjustable holder 25b configured to accommodate the at least one tube 20 of varying dimensions including pediatric tube 25. When the biological samples comprise blood samples, the control unit 46 measures erythrocyte sedimentation rate (ESR) by detecting changes in a blood-plasma interface over time. The control unit 46 directs the drive unit 17 to move the optical module 16 at predetermined time intervals to generate a measurement curve representing the erythrocyte sedimentation rate (ESR) over time. The multiple sequential measurements from different vertical positions of the optical module 16 are plotted against their corresponding time points to generate a sedimentation curve, as illustrated in FIG. 13. The control unit 46 analyzes this sedimentation curve to calculate the ESR using a quadratic equation (ESR = Ax² + Bx + C) where x represents the difference between initial and final sedimentation heights, with coefficients calibrated against the Westergren method.
[0100] FIG. 11A and FIG. 11B illustrate graphs representing comparison results between the apparatus 10 measurements and the Westergren method using different aperture configurations in accordance with an embodiment of the present invention.
[0101] FIG. 11A illustrates a graph representing the comparison with the Westergren method when using rectangular apertures for the set of optical elements 22a, 22b in accordance with an embodiment of the present invention. The graph presents a scatter plot of erythrocyte sedimentation rate (ESR) values obtained from 89 different blood samples. Each point on the graph represents an individual blood sample where the x-axis coordinate indicates the ESR value measured using the Westergren method, and the y-axis coordinate indicates the corresponding ESR value measured using the apparatus 10 with rectangular apertures in the set of optical elements 22a, 22b. The rectangular apertures used in this experimental validation have width between 0.1 mm to 2 mm and length between 0.5 mm to 4 mm. The graph includes a linear regression line that demonstrates the correlation between the two measurement methods. The coefficient of determination (R²) is 0.9267, indicating that 92.67% of the variation in the apparatus measurements can be explained by the Westergren method values. This high correlation confirms the apparatus 10 provides measurements closely aligned with the accepted the Westergren method. The rectangular apertures demonstrate particularly strong performance for blood samples with ESR values below 15 mm/hr, where the extended vertical dimension of the rectangular shape enables more precise detection of the blood-plasma interface as it moves through the measurement range.
[0102] FIG. 11B illustrates a graph representing the comparison with the Westergren method when using circular apertures for the set of optical elements 22a, 22b in accordance with an embodiment of the present invention. Similar to FIG. 11A, this graph presents a scatter plot of ESR values, but with data from 26 different blood samples. The x-axis indicates ESR values obtained using the Westergren method, while the y-axis shows the corresponding values measured using the apparatus 10 with circular apertures. The circular apertures used in this experimental validation have diameters between 0.1 mm to 2 mm. The graph includes a linear regression line demonstrating the relationship between the two measurement methods. The coefficient of determination (R²) is 0.9204, indicating that 92.04% of the variation in the apparatus measurements with circular apertures can be explained by the Westergren method values. While this represents a strong correlation, it is comparable to the correlation achieved with rectangular apertures as shown in FIG. 11A. The comparative analysis presented in FIG. 11A and FIG. 11B demonstrates several important findings regarding aperture design in the set of optical elements 22a, 22b. First, both aperture configurations achieve high correlation with the Westergren method, confirming the fundamental accuracy of the apparatus measurement approach. However, rectangular apertures provide enhanced measurement accuracy, particularly for lower ESR values below 100 mm/hr where precise detection becomes more challenging. The data points in FIG. 11A show tighter clustering around the regression line compared to FIG. 11B, indicating more consistent measurements across the full range of ESR values. Additional testing performed without any apertures (data not shown in these figures) resulted in a correlation of only 84% with the Westergren method, confirming that the presence of apertures significantly improves measurement precision. The rectangular aperture configuration was tested with a substantially larger sample size (89 samples versus 26 samples for circular apertures), providing stronger statistical validation of its measurement accuracy. These results collectively indicate that while both aperture shapes deliver clinically acceptable performance, the rectangular aperture configuration offers superior technical characteristics for ESR measurement across the full clinical range.
[0103] FIG. 12 illustrates a graph representing the correlation achieved between the apparatus 10 with circular apertures and the Westergren method for measuring erythrocyte sedimentation rate (ESR) in accordance with an embodiment of the present invention. The graph presents a comprehensive scatter plot containing data from 66 EDTA blood samples analyzed using both measurement methods. Each data point represents an individual blood sample with its x-axis coordinate showing the ESR value measured by the apparatus 10 with circular apertures in the set of optical elements 22a, 22b, and the y-axis coordinate showing the corresponding ESR value obtained using the Westergren method. The circular apertures implemented in this validation study have precisely controlled diameters between 0.1 mm to 2 mm, manufactured to maintain consistent optical properties across all measurement channels. The graph includes a linear regression line demonstrating the mathematical relationship between the two measurement approaches. The coefficient of determination (R²) exceeds 0.9561, indicating that more than 95.61% of the variation in the Westergren method values can be explained by the apparatus measurements. This exceptionally high correlation confirms the circular aperture configuration achieves measurement accuracy comparable to the internationally recognized reference method. The circular aperture design narrows the transmitted light beam to increase detection accuracy of the blood/plasma interface to within ±1 mm precision. The tight clustering of data points around the regression line across the entire measurement range (from low ESR values below 20 mm/hr to elevated values above 100 mm/hr) demonstrates the consistent performance of the optical measurement system across diverse clinical samples.
[0104] FIG. 13 illustrates a graph representing the representative sedimentation curves for blood samples with high and low ESR values in accordance with an embodiment of the present invention. The graph plots sedimentation height (measured in millimeters) on the y-axis against time (measured in minutes) on the x-axis for two distinctly different blood samples analyzed using the apparatus 10. The upper curve represents a blood sample with low ESR value, while the lower curve represents a sample with high ESR value. The high-ESR sample curve displays a characteristic S-shaped pattern with three distinct phases: an initial lag phase with minimal sedimentation, followed by a rapid sedimentation phase with steep slope, and concluding with a packing phase where sedimentation rate decreases. This nonlinear sedimentation profile reflects the complex aggregation behavior of erythrocytes in inflammatory conditions. In contrast, the low-ESR sample demonstrates a nearly linear decrease in sedimentation height over the measurement period, indicating minimal erythrocyte aggregation typical of non-inflammatory states. The apparatus 10 captures these distinct sedimentation profiles by measuring the blood-plasma interface position at regular intervals (typically every 1-2 minutes) over a 15-30 minute period. The sedimentation height difference between initial and final measurements correlates with the standard one-hour ESR value through the quadratic equation: ESR (mm/h) = A×X² + B×X + C, where X represents the measured height difference. The coefficients A, B, and C are determined through a calibration process that involves the following steps: First, a set of at least 50 diverse blood samples covering low (0-20 mm/h), medium (21-60 mm/h), and high (>60 mm/h) ESR ranges are measured using both the apparatus 10 and the reference Westergren method. For each sample, the sedimentation height difference X measured by the apparatus 10 is recorded alongside the corresponding Westergren ESR value. Multiple regression analysis is then performed on this calibration dataset to derive the optimal values for coefficients A, B, and C that minimize the mean squared error between the calculated ESR values and the reference Westergren values. The typical ranges for these coefficients are: A ranges from 0.005 to 0.05, B ranges from 1.5 to 2.5, and C ranges from -3 to 3. The regression analysis typically achieves an R² value exceeding 0.95, indicating excellent correlation with the Westergren method. The calibration procedure is performed during the manufacturing validation process, and the apparatus 10 is programmed with these coefficients to enable accurate conversion of measured sedimentation differences to standardized ESR values. By utilizing this sedimentation curve and calibrated quadratic equation, the invention enables accurate and reliable ESR determination from the device measurements. The automated measurement of sedimentation height at regular intervals improves the precision and reproducibility of the ESR assessment compared to manual methods.
[0105] The present disclosure provides technical advancement related to automated blood analysis systems. This advancement addresses the limitations of existing ESR measurement solutions by implementing precision optical elements with controlled aperture dimensions. The disclosure involves specific optical path control techniques through strategically positioned apertures, which offer significant improvements in measurement accuracy with correlation exceeding 95% with the Westergren method. By implementing pulse mode operation of light sources combined with precise optical elements, the disclosed invention enhances ESR measurement capabilities across diverse sample conditions, resulting in reliable diagnostic information for clinical assessment of inflammatory and pathological conditions using standard blood collection tubes without additional processing steps.
[0106] The present disclosure improves measurement accuracy through the implementation of a set of optical elements positioned in the light path. The set of optical elements enable precise detection of the blood-plasma interface, resulting in more reliable ESR measurements across diverse sample conditions.
[0107] The present disclosure eliminates the need for specialized ESR tubes by enabling direct measurement from primary EDTA blood collection tubes. This reduces sample processing steps, decreases overall analysis time, and minimizes potential errors from sample transfer.
[0108] The present disclosure enhances light detection through pulse mode operation of the LED emitter. This operational mode generates higher intensity light bursts that penetrate effectively through blood samples with varying opacity levels and tubes with paper labels.
[0109] The present disclosure accommodates varying tube sizes through the adjustable holders in tube receiving unit. This design feature enables analysis of both standard and pediatric samples without requiring manual adjustments or separate adapters.
[0110] The present disclosure achieves strong correlation with the Westergren method. This high level of agreement ensures reliable clinical results while substantially reducing the measurement time required for ESR determination.
[0111] The present disclosure ensures precise vertical scanning through a drive unit comprising a stepper motor coupled to a lead screw, guided by guide rods, and monitored by a position detector. This mechanical arrangement enables accurate tracking of the sedimentation interface at regular intervals.
[0112] The present disclosure maintains consistent optical alignment through vertically oriented printed circuit boards for both light emitting and receiving assemblies. This configuration eliminates alignment errors associated with bent LED/photodiode arrangements used in conventional systems.
[0113] In the above description, numerous specific details are set forth such as examples of some embodiments, specific components, devices, methods, in order to provide a thorough understanding of embodiments of the present invention. It will be apparent to a person of ordinary skill in the art that these specific details need not be employed and should not be construed to limit the scope of the subject matter.
[0114] In the development of any actual implementation, numerous implementation-specific decisions must be made to achieve the developer's specific goals, such as compliance with system-related and business-related constraints. Such a development effort might be complex and time consuming, but may nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill. Hence as various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
The foregoing description of embodiments is provided to enable any person skilled in the art to make and use the subject matter of the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the novel principles and subject matter disclosed herein may be applied to other embodiments without the use of the innovative faculty. It is contemplated that additional embodiments are within the true scope of the disclosed subject matter.
,CLAIMS:WE CLAIM:
1. An apparatus (10) for analyzing biological samples, the apparatus (10) comprising:
a housing (9);
a tube receiving unit (42) attached to the housing (9), wherein the tube receiving unit (42) is configured to receive at least one tube (20), wherein the at least one tube (20) contains biological samples;
an optical module (16) housed inside the housing (9), wherein the optical module (16) is operatively coupled with the tube receiving unit (42), wherein the optical module (16) comprises at least one light emitting assembly (16a) and at least one light receiving assembly (16b), wherein the at least one light emitting assembly (16a) is configured to emit light, and wherein the at least one light receiving assembly (16b) is configured to receive the emitted light;
a drive unit (17) configured to move the optical module (16) relative to the at least one tube (20);
characterized in that:
a set of optical elements (22a, 22b); and
a control unit (46),
wherein the set of optical elements (22a, 22b) is positioned in a light path between the light emitting assembly (16a) and the light receiving assembly (16b), wherein the set of optical elements (22a, 22b) focus the emitted light towards the light receiving assembly (16b), wherein the biological samples obstruct the light path, wherein the light receiving assembly (16b) detects intensity of light received at the light receiving assembly (16b), and wherein the control unit (46) measures changes in the biological samples in the at least one tube (20) based on the intensity of light received at the light receiving assembly (16b).
2. The apparatus (10) as claimed in claim 1, wherein the biological samples comprise blood samples, and wherein the apparatus (10) is configured to measure erythrocyte sedimentation rate (ESR) in the blood samples by detecting changes in a blood-plasma interface over time.
3. The apparatus (10) as claimed in claim 1, wherein the tube receiving unit 42 comprises a first plurality of slots (42a, 42b, 42c…), wherein each slot from the first plurality of slots (42a, 42b, 42c…) receives the at least one tube 20, wherein the optical module (16) comprises an optical module housing (19) having a second plurality of slots (18a, 18b, 18c…), wherein the second plurality of slots (18a, 18b, 18c…) are coaxial with the first plurality of slots (42a, 42b, 42c…)to receive and align the tube receiving unit (42), and wherein the at least one light emitting assembly (16a) and the at least one light receiving assembly (16b) are housed inside the optical module housing (19).

4. The apparatus (10) as claimed in claim 1, wherein the at least one light emitting assembly (16a) comprises a first printed circuit board (24) having at least one Light Emitting Diode (LED) emitter (40) mounted thereon, wherein a first optical element (22a) from the set of optical elements (22a, 22b) is positioned between the at least one tube (20) and a first spacer (38a) to direct light rays from the LED emitter (40) towards the at least one tube (20), and wherein the first spacer (38a) is positioned between the first printed circuit board (24) and the first optical element (22a) to prevent light leakage.
5. The apparatus (10) as claimed in claim 1, wherein the at least one light receiving assembly (16b) comprises a second printed circuit board (30) having at least one receiver (36) mounted thereon, wherein a second optical element (22b) from the set of optical elements (22a, 22b) is positioned between the at least one tube (20) and a second spacer (38b) to direct transmitted light from the at least one tube (20) towards the at least one receiver (36), and wherein the second spacer (38b) is positioned between the second printed circuit board (30) and the second optical element (22b) to prevent light leakage.
6. The apparatus (10) as claimed in claim 1, wherein the drive unit (17) comprises a stepper motor (32) operatively coupled to a lead screw (26) through a coupler (34), at least one guide rod (28), and a position detector (44), wherein the lead screw (26) is attached to an output shaft (32a) of the stepper motor (32) for converting rotational motion to linear motion to enable vertical movement of the optical module (16), wherein the optical module (16) is guided along at least one guide rod (28), and wherein the position detector (44) is operatively coupled with the optical module (16) to monitor and control a vertical movement of the optical module (16) during measurement.
7. The apparatus (10) as claimed in claim 1, wherein the set of optical elements (22a, 22b) comprises lens, or an aperture configured in one of circular, rectangular, triangular, or polygonal shape, and wherein the set of optical elements (22a, 22b) is configured to control the light path between the light emitting assembly (16a) and the light receiving assembly (16b).
8. The apparatus (10) as claimed in claim 4, wherein the control unit (46) is configured to operate the at least one LED emitter (40) in a pulse mode at a predetermined frequency and at a predetermined intensity, and wherein the predetermined frequency of the pulse mode is between 2 Hz to 500 Hz.
9. The apparatus (10) as claimed in claim 4, wherein the at least one receiver (36) comprises a photodiode configured to detect transmitted light at predetermined intensity, and wherein the control unit (46) processes signals from the photodiode for measuring the changes in the biological samples.
10. The apparatus (10) as claimed in claim 1, wherein the first printed circuit board (24) and the second printed circuit board (30) are vertically oriented within the optical module (16).
11. The apparatus (10) as claimed in claim 1, wherein the tube receiving unit (42) comprises an adjustable holder (25b) configured to accommodate the at least one tube (20) of varying dimensions including pediatric tube (25).
12. The apparatus (10) as claimed in claim 1 further comprises a display (14) configured to present measurement results and a set of operational parameters to a user.
13. The apparatus (10) as claimed in claim 1, wherein the control unit (46) directs the drive unit (17) to move the optical module (16) at predetermined time intervals to generate a measurement curve representing the erythrocyte sedimentation rate (ESR) over time.
14. The apparatus (10) as claimed in claim 1, wherein the apparatus (10) comprises a quality control element (100) having predetermined height markers, wherein the quality control element (100) is configured to validate measurement accuracy of the apparatus (10), and wherein the quality control element (100) comprises at least three predefined height levels (102, 104, 106) corresponding to different blood interface levels.
15. A method for analyzing biological samples, the method comprising the steps of:
receiving at least one tube (20) containing biological samples in a tube receiving unit (42);
emitting light from a light emitting assembly (16a) of an optical module (16);
receiving the emitted light at a light receiving assembly (16b) of the optical module (16),
positioning a set of optical elements (22a, 22b) in a light path between the light emitting assembly (16a) and the light receiving assembly (16b), the set of optical elements (22a, 22b) focusing the emitted light towards the light receiving assembly (16b) such that the biological samples obstruct the light path and enabling the light receiving assembly (16b) for detecting intensity of light received at the light receiving assembly (16b);
moving the optical module (16) relative to the at least one tube (20) using a drive unit (17); and
measuring, by a control unit (46) of the apparatus (10), changes in the biological samples based on the detected light intensity at different positions of the optical module (16) relative to the at least one tube (20).