FORM 2THE PATENTS ACT 1970(39 of 1970)&The Patent Rules 2005PROVISIONAL SPECIFICATION(see sections 10 & rule 13)TITLE OF THE INVENTION“ INCLUSION DETECTION”
2. APPLICANT (S)
NAME NATIONALITY ADDRESS
Sahajanand Technologies Pvt. Ltd. Indian Company Sahajanand House, Parsi Street, Saiyedpura, Surat 395003, Gujarat, India
3. PREAMBLE TO THE DESCRIPTION
PROVISIONAL SPECIFICATION
The following specification describes the nature of the invention

INCLUSION DETECTION
FIELD OF INVENTION
The present invention in general relates to a system and apparatus for determining the presence of an inclusion in a gemstone.
BACKGROUND
Typically, a raw gemstone i.e. the gemstone as found in its natural state, has a highly irregular geometry and comprises many inclusions. A series of steps are involved in processing the raw gemstone to obtain a finished gemstone. Major steps involved in the processing are obtaining the 3D profile of the gemstone, selecting a best shape for the finished gemstone to be cut from the raw gemstone and finally cutting the raw gemstone into the selected shape. For selecting the best shape for the gemstone, precise information of the geometry of the gemstone is required. This information not only includes the 3D profile of the gemstone but also information regarding the presence of any inclusion or marking in the gemstone.
Markings are imperfections found on the surface of a gemstone. Markings are surface blemishes present on a gemstone. Markings may be inherently present in gemstone or may be created during the processing or polishing of the gemstone. Unlike an inclusion, a marking is superficial and not within the bulk or under the surface of the gemstone.


Inclusions are characteristics that occur inside a gemstone. They are usually called flaws, because their presence affect the clarity of the gemstone, making it less brilliant because they interfere with light as it passes through the stone. In certain cases, inclusions can also make a gemstone vulnerable to shattering.
The best shape for the finished gemstone is so chosen that it avoids the presence of any inclusion in the finished gemstone. If at all the presence of an inclusion in the finished gemstone cannot be avoided, the shape chosen is such that the impact of presence of the inclusion, on the brilliance of the finished gemstone, is minimized. Avoiding the presence of an inclusion in the culet is especially important in case of gemstones such as diamonds where the monetary value of the gemstone depends not only on the size but the brilliance of the gemstone.
Thus, the information regarding the presence of an inclusion in the gemstone is very essential in determining a best shape for the finished gemstone to be cut from the raw gemstone in order to obtain a maximum value finished stone.
OBJECTS OF THE INVENTION
An object of the present invention is to determine an inclusion in a gemstone.
Another object of the present invention is that it can be used in conjunction with a profile mapping apparatus and/ or system to decide a best suited plan for the gemstone.
Yet another object of the present invention is to distinguish between an inclusion and a marking.


Various modifications of the disclosed objects, as well as alternate objects of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. It is therefore contemplated that such modifications can be made without departing from the spirit or scope of the present invention as defined.
DESCRIPTION
The subject matter described herein, is a system and apparatus for determining the presence of an inclusion in a gemstone and distinguishing an inclusion from a marking.
To determine the presence of an inclusion in a gemstone by conventional methods, a very high level of precision and skill is required. The conventional method comprises polishing a small area of the surface of the gemstone so as to make that area very smooth. This area is called window. The window region is illuminated using a beam of light falling normal to the window. The gemstone is observed through the window holding the gemstone strictly perpendicular to the line of sight. This requires a high level of expertise and any lack in precision leads to loss in value of the gemstone.
With the advent of technology, various computerized systems, are employed in processing the raw gemstone to obtain the finished gemstone. These systems carry out all the major steps involved in processing the raw gemstone. These systems obtain the 3D profile of the gemstone, provide to the user the best suited shapes for the finished gemstone, provide laser marks on the gemstone, cut and polish the gemstone. However, determining the presence of an inclusion and distinguishing an inclusion from a marking remains a critical task in the processing of a gemstone.


Proposed herein is a method and apparatus of determining the presence of an inclusion in the gemstone which does not require high level of expertise. The method and apparatus work in a computer environment.
An embodiment of the subject matter illustrated in Fig. 1, describes an apparatus 100 for determining the presence of an inclusion in a gemstone.
The apparatus 100 comprises a means for mounting and rotating the gemstone 105. The means for mounting and rotating the gemstone 105 may be any rotating surface and is typically a turntable 110. However, applicant intends to encompass within the language any structure presently existing or developed in future that performs the same function. A first light source 115 is used to illuminate the gemstone 105 from behind to create a silhouette of the gemstone. The first light source 115 may be a collimated light source or alternatively an ordinary light source. A second light source 120 is used for illuminating a point, line or grid on the surface of the object to perform structured light triangulation. In one example of the apparatus described herein, the second light source 120 is a laser light source.
A means for scanning 125 the gemstone is disposed at a predefined angle from the second light source 120. Examples of the means for scanning 125 includes, but is not restricted to, a camera, preferably a CCD camera, a scanner, or a digitizer and encompasses within the language any structure presently existing or developed in future that performs the same function. The means for scanning 125 captures a plurality of silhouette and also light from the second light source 120 being reflected from the


gemstone 105 and provides as inputs, these captured signals to a means for processing signals 130.
The means for processing 130 processes the input signals and generates a 3D profile for the gemstone 105. The means for processing 130 also stores the input signal as well as the 3D profile of the gemstone 105. This stored information is required by the means for processing 130 while determining the presence of an inclusion. One or more third light source 135, called as baselight is provided to illuminate the gemstone so as to facilitate the means for scanning 125 to capture the image of the gemstone 105. Baselight 135 is an ordinary diffused or direct light source, such as a source of white light or any other coloured light source and can be placed at any appropriate position in the apparatus 100.
The apparatus 100 performs silhouette mapping and structured light triangulation to generate a true 3D profile of the gemstone which is a prerequisite for determining the presence of an inclusion in the gemstone.
In an embodiment of the present invention, the method and apparatus for determining the presence of an inclusion in a gemstone, operates in conjunction with another system employed to generate the 3D profile of the gemstone. The method and apparatus described herein takes as an input, the 3D profile of the gemstone, from the system employed to generate the 3D profile of the gemstone. Thus, the method and apparatus for determining the presence of an inclusion in the gemstone can be made to function in conjunction with any other computerized system employed for generating the 3D profile of the gemstone by any image processing technique.


Fig. 2 illustrates a method 200 for determining the presence of an inclusion in a gemstone, in accordance with an embodiment of the subject matter, by means of a flowchart.
Method 200 is a software implemented method that works in a computer environment. The method 200 is preferably implemented in the aforementioned means for processing 130, wherein the 3D profile of the gemstone 105 is generated and stored.
Method 200 is initiated by step 205 wherein, a true 3D profile of the gemstone 105 is generated. The true 3D profile of the gemstone 105 is generated by employing image processing methods that typically involve silhouette mapping and structured light triangulation. Once the 3D profile of the gemstone 105 is generated, all image data relating to every point on the surface of the gemstone 105 is available and stored in the means for processing 130.
In step 210, image data of one frame is captured. The image data is captured by the means for scanning 125, which may be a camera, preferably a CCD or CMOS- CCTV camera or a scanner. The image data in the frame comprises the information about the surface of the gemstone 105 covered in that frame and the points lying therein. The image data captured is analyzed for any point that appears as a probable inclusion in step 215.
The turntable 110 is rotated by predetermined angle of rotation in step 220 and in the next step i.e. step 225 of the method 200, another frame of image data corresponding to the new position of the gemstone 105 is captured. A displacement in the position of the point that appears to be a probable inclusion is observed. In step 230 the displacement of the probable inclusion is calculated using the image data captured in two frames.


The image data of points on the surface of the gemstone 105 is available in the form of the generated 3D profile and is stored in the means for processing 130. The means for processing 130 can compute the displacement of a point on the surface taking into account the distance of that point from a notional central line of the gemstone 105 and the predetermined angle of rotation of the turntable 110. In step 235, the displacement of the probable inclusion, calculated in step 230, is compared to the displacement of a point on the surface of the gemstone 105. If the displacement of the probable inclusion is lesser than the displacement of the point on the surface, the probable inclusion is actual inclusion as depicted in step 245. However, if the displacement of the probable inclusion is not less than or is equal to the displacement of the point on the surface, the point is tagged as a marking in step 250.
In certain cases, upon rotating the turntable 110 by predetermined angle of rotation the displacement of the probable inclusion may appear to have shifted in the opposite direction. For example, if the turntable 110 is rotated towards the left of an observer, the probable inclusion may appear to have shifted towards the right of the observer. In these cases the inclusion is present, away from the field of view of the means for scanning 125, behind the notional central line of the gemstone 105.
The order in which the method 200 is described is not intended to be construed as a limitation, and the steps described can be combined in other ways obvious to a person skilled in the art. Additionally, individual blocks may be added or deleted from the method without departing from the spirit and scope of the subject matter described.


Although the subject matter has been described with reference to certain preferred embodiments thereof, other embodiments are possible. As such, the spirit and scope of the subject matter described herein should not be limited to the description of the embodiment contained herein.