Technical field
[0001] The present invention relates to an equipment 5 for carrying out a
spectroscopic analysis control of moving objects, for example a spatially resolved infrared
spectroscopy analysis of drugs.
Background
10 [0002] There are equipments with probes designed to be placed over moving
objects. These probes have a surface on which illumination optical fibres and measurement
optical fibres open out. A problem with known probes is that some objects or segments of
objects are not observed by any fibre or are not observed well enough for an individualised
spectroscopic analysis per object to be possible.
15 [0003] The document WO2006116569 describes an optical reflectance
measurement applied to a portion of the human body. The document WO2014116277
describes a transcutaneous sensor geometry. In these types of measurements, the observed
objects are not moving and are not particularly small, and the problem mentioned above
does not arise.
20 [0004] The document EP1674859 describes a detector for detecting a certain type
of object among a plurality of objects. This document focuses on the treatment of the data
received and does not mention the problem mentioned above.
[0005] The document EP3575776 describes a measurement system for small volume
items in bulk. In this system, some fibres are above and below the objects, which makes it
25 particularly complicated.
Summary of the invention
[0006] An object of the present invention is a measurement equipment arranged for
improved observation of moving objects, in particular for the purpose of a spatially resolved
30 infrared spectroscopic analysis of said individual objects.
[0007] For this purpose, the invention proposes a measurement equipment
comprising a probe for observing objects moving along a longitudinal direction, preferably
2
for carrying out a spatially resolved spectroscopic analysis on said objects, a triggering device
offset from the probe along the longitudinal direction, and a control unit;
the probe comprising:
 a surface extending along the longitudinal direction and along a lateral direction
perpendicular to the longitudinal 5 direction,
 one or more first optical fibres opening out onto said surface and arranged to
emit electromagnetic radiation from at least one source, each first optical fibre
having a first acceptance cone,
 second optical fibres opening out onto said surface, and arranged to capture
10 electromagnetic radiation and transmit it to a receiving device, each second
optical fibre having a second acceptance cone, the second optical fibres being
offset from the first optical fibre or fibres along the longitudinal direction and
located on a same side of the first optical fibre or fibres;
the probe being such that at least one of the second acceptance cones
15 intersects at least one first acceptance cone at less than 10 mm of said surface;
the triggering device being configured to detect the moving objects; and
the measurement equipment being configured to activate the observation of
the objects by the probe in response to their detection by the triggering device.
[0008] The inventors have realised that the problems with current probes come in
20 particular from their arrangement in which second optical fibres (capture optical fibres) are
distributed into two lateral groups on either side of first optical fibres (illumination optical
fibres). This is because in this known arrangement the central area of the conveyor is too far
away from the second optical fibres to be visible. The inventors first changed the orientation
of the known probe with respect to the moving direction, but then the second optical fibres
25 are distributed over such a long length in the direction of moving that the number of images
taken during a passage of an object under the probe becomes insufficient to make a quality
spectroscopic analysis.
[0009] In the probe according to the invention, all the second optical fibres are offset
along the direction of moving of the first optical fibre or fibres and located on a same side of
30 the first optical fibre or fibres. This allows, for a given number of second optical fibres, a
better lateral distribution of the second optical fibres to eliminate the areas where the
3
objects are not visible. The smaller objects located in the centre of the conveyor are therefore
better observed in particular.
[0010] An objective of the invention is to be able to make rapid analyses in order to
have a good flow of objects. The total number of optical fibres is then a constraint because
distributing the optical fibres over a small enough distribution surface 5 of the assembly of
optical fibres in the orientation of the moving allows for a good spatial resolution at high
moving speeds, while avoiding unnecessary optical fibres. The distribution of the fibres
according to the invention allows a better distribution for a given total number of optical
fibres.
10 [0011] In addition, the number of effectively active second optical fibres is also a
constraint, as the length of the treatment of the captured information increases with the
number of second optical fibres. In the invention, the better lateral distribution of the latter
allows to reduce the number of active second optical fibres, and thus the treating time for
the information per measurement. Thus, the frequency of measurements can be increased,
15 and ultimately, the measured results can be improved because they can be based on a larger
number of measurements (which can be averaged to reduce the signal-to-noise ratio, for
example).
[0012] The arrangement of the optical fibres according to the invention also allows
each object to be observed via photons that have travelled widely varying distances within
20 the objects. This is because when the electromagnetic radiation penetrates an object
shallowly, it emerges close to its point of entry, and is then generally captured by a second
optical fibre close to the first optical fibre that emitted it; whereas when electromagnetic
radiation penetrates deeper into an object, it emerges further away from its point of entry,
and is then generally captured by a second optical fibre further from the first optical fibre
25 that emitted it. Thus, a large variation in the distance between the first and second optical
fibres allows to provide a richer spectral information.
[0013] Furthermore, as in the invention the first and second optical fibres are
sufficiently close that their acceptance cones are dissociated over a distance of at most 10
mm, the capture of electromagnetic radiation reflected by the surfaces of the objects located
30 within this distance is particularly low. This is a great advantage in spatially resolved infrared
spectroscopy where the scattered electromagnetic radiation is of interest and the reflected
electromagnetic radiation is harmful.
4
[0014] Furthermore, since the first and second fibres are offset in the direction of
moving, the objects are illuminated over a clearly defined moving length and are detected
over a defined moving length, which simplifies the treatment of the received data.
[0015] Moreover, since the maximum width for distributing all the optical fibres is a
technical constraint, the distribution of the fibres of the invention 5 allows to cover a
particularly large portion of this maximum width.
[0016] The probe is of the type used for analytical techniques referred to as Single
Particle Counter where each photon is counted.
[0017] Since the second optical fibres are offset from the first optical fibre or fibres
10 along the longitudinal direction and located on a same side of the first optical fibre or fibres,
and the second acceptance cones are disassociated from any first acceptance cone by a fixed
distance of at most 10 mm measured from said surface:
 there is a first reference plane at at most 10 mm from that portion of the surface
into which the first optical fibres opens out such that each first optical fibre has
15 a first acceptance cone whose intersection with the first reference plane forms
a first circle, the first circles of all the first optical fibres of the probe being
inscribed in a first reference rectangle,
 there is a second reference plane at at most 10 mm from the portion of the
surface onto which the second optical fibres opens out such that each second
20 optical fibre has a second acceptance cone whose intersection with the second
reference plane forms a second circle, the second circles of all the second optical
fibres of the probe being inscribed within a second reference rectangle, and
 the first reference rectangle and the second reference rectangle do not overlap.
[0018] Although some characteristics are described as relating to several first optical
25 fibres, it should be understood that they are also appropriate in the case where the probe
comprises only one first optical fibre, unless explicitly stated otherwise.
[0019] The triggering device allows an object to be detected before it arrives in the
viewing area of the probe, so as to trigger the activation of the probe at the moment the
object arrives in the viewing area of the probe. The triggering device is upstream of the probe
30 in relation to the moving of the objects. Preferably, the triggering device sends information
to a control unit in order to activate or deactivate the probe. When the triggering device
starts to detect the object, it sends an object detection information to the control unit, which
5
uses this information and the moving linear speed of the conveyor to calculate the moment
of activation of the probe. When the triggering device stops detecting the object, it sends a
conveyor detection information to the control unit, which uses this information and the
moving linear speed of the conveyor to calculate the moment of deactivation of the probe.
[0020] In the scope of the present document, an "activated" probe 5 is a probe that is
capable of making an observation. An "activation" of the probe preferably comprises an
activation of at least some of the second optical fibres, and a "deactivation" of the probe
preferably comprises a deactivation of the activated second optical fibres. It is possible, while
remaining within the scope of the present invention, that the first optical fibre or fibres
10 remain activated even when the probe is deactivated.
[0021] According to an embodiment, the triggering device comprises two detecting
elements offset from each other along the lateral direction. Preferably, each detection
element detects a point on the conveyor. An information related to each of the detecting
elements, i.e. each of the points, is sent to the control unit.
15 [0022] According to one embodiment, each detection element is on a separate laser
detector, the laser detectors being arranged to be displaceable along the lateral direction.
Their lateral position can thus be adapted mechanically to the size of the objects on the
conveyor. An example of a suitable laser detector is a Keyence LK-G detector or a Panasonic
HL-C detector.

CLAIMS
1. A measurement equipment (500) comprising a probe (1) for observing
objects (2) moving along a longitudinal direction (202), preferably for carrying out a spatially
resolved spectroscopic analysis on said objects (2), a triggering device (5 8) offset from the
probe (1) along the longitudinal direction (202), and a control unit (510);
the probe (1) comprising:
 a surface (100) extending along the longitudinal direction (202) and along a
lateral direction (201) perpendicular to the longitudinal direction (202),
10  one or more first optical fibres (10) opening out onto said surface (100) and
arranged to emit electromagnetic radiation from at least one source (5), each
first optical fibre (10) having a first acceptance cone (11),
 second optical fibres (20) opening out onto said surface (100), and arranged to
capture electromagnetic radiation and transmit it to a receiving device (6), each
15 second optical fibre (20) having a second acceptance cone (21), the second
optical fibres (20) being offset from the first optical fibre or fibres (10) along the
longitudinal direction (202) and located on a same side of the first optical fibre
or fibres (10);
the probe (1) being such that at least one of the second acceptance cones (21)
20 intersects at least one first acceptance cone (11) at less than 10 mm of said surface (100);
the triggering device (8) being configured to detect the moving objects (2); and
the measurement equipment (500) being configured to activate the
observation of the objects (2) by the probe (1) in response to their detection by the triggering
device (8).
25
2. The measurement equipment according to claim 1, wherein the triggering
device (8) comprises two detecting elements (81a, 81b) offset from each other along the
lateral direction (201).
30 3. The measurement equipment according to the preceding claim, wherein
the triggering device (8) comprises separate laser detectors (82a, 82b), the laser detectors
(82a, 82b) being arranged to be displaceable along the lateral direction (201), each of the
laser detectors (82a, 82b) comprising one of the detecting elements (81a, 81b).
4. The measurement equipment of claim 2, wherein the triggering device (8)
emits a beam (83) extending along the lateral direction (201), the detecting 5 elements (81a,
81b) each comprising a separate segment of a detector arranged to capture the beam (83)
after reflection on the objects (2).
5. The measurement equipment according to any of the preceding claims,
10 wherein the second optical fibres (20) are distributed over the surface (100) over a
longitudinal extension (24) and over a lateral extension (25) such that the longitudinal
extension (24) is less than the lateral extension (25).
6. The measurement equipment according to any of the preceding claims,
15 wherein the second optical fibres (20) are distributed over a greater width than the first
optical fibre or fibres (10), the width being taken along the lateral direction (201).
7. The measurement equipment according to any of the preceding claims,
wherein the second optical fibres (20) are distributed over a smaller length than the first
20 optical fibre or fibres (10), the length being taken along the longitudinal direction (202).
8. The measurement equipment according to any of the preceding claims,
wherein the first optical fibres (10) are distributed in at most three laterally extending rows.
25 9. The measurement equipment according to any of the preceding claims,
wherein the second optical fibres (20) are distributed in at most three laterally extending
rows.
10. A probe according to any of the preceding claims, wherein the second
30 optical fibres (20) are on average further apart from each other than the first optical fibres
(10).
11. A measurement system (9) comprising a measurement equipment (500)
according to any of the preceding claims, at least one source (5) of electromagnetic radiation,
a receiving device (6), and a conveyor (3) arranged to transport the objects (2) along the
longitudinal direction (202), so that the objects (2) are detectable by the triggering device (8)
on a portion of the conveyor (3) and are observable by the probe (1) on 5 a portion of the
conveyor (3).
12. The measurement system (9) according to the preceding claim, further
comprising the objects (2), wherein the probe (1) is above the objects (2), the measurement
10 system (9) being arranged so that the top (2a) of the objects (2) is located between the
surface (100) and at least one intersection between a first (11) and a second (21) cone of
acceptance.
13. The measurement system (9) according to claim 11 or 12, further
15 comprising a spectral analysis device (7) arranged to receive information from the receiving
device (6).
14. A use of a measurement equipment (500) according to any one of claims 1
to 10, or a measurement system (9) according to any one of claims 11 to 13, wherein the first
20 optical fibre or fibres (10) emit electromagnetic radiation towards the objects (2), and the
second optical fibres (20) receive electromagnetic radiation from the objects (2).
15. The use according to the preceding claim, wherein a detection of an object
(2) by the triggering device (8) leads to an activation of the probe (1).
25