Material identification device and method

Abstract

The aim is to be able to determine the colour and / or other properties besides the NIR spectrum of objects in the stream. The invention relates to an apparatus (100) for classification of an object (102), comprising a scanning element configured to redirect at least one illumination beam and to shift a plurality of inspection zones and illuminated areas in a first direction relative to the object, a processing circuit configured to perform a second zone collection function configured to collect second zone data related to optical radiation emitted by the object in the second inspection zone, a third zone collection function configured to collect third zone data related to optical radiation emitted by the object in the third inspection zone, and a classification function configured to classify the object based on the second zone data and the third zone data.

Description

[Technical field]

[0001] The present invention relates to apparatus for detecting objects, and more particularly to such apparatus that include a spectroscopic system for detecting and analyzing light-responsive events from the object. [Background technology]

[0002] Throughout a wide range of industries, the identification, detection, classification and sorting of various objects is frequently needed and desired.

[0003] In its simplest form, manual identification of objects by a person may be advantageously employed when a limited number of objects are to be identified, classified and sorted. A person may then identify and classify the relevant objects based on his / her knowledge. However, this type of manual identification is tedious and prone to errors. Also, the experience level of the operator will significantly affect the outcome of the task performed by that operator. Furthermore, the above kind of manual identification has the disadvantage of a slow identification speed.

[0004] Thus, in industry, the identification, sorting, and separation of large quantities of objects is often performed by machines, which are supplied in the form of a continuous stream of objects. Such machines are generally faster than workers and can operate for longer periods, thus providing an enhancement in overall throughput. Machines of this kind are used, for example, in agriculture for fruits and vegetables, and in recycling to identify and separate objects and materials to be recycled.

[0005] Machines of the above types generally have some form of sensor arrangement that is used to identify the object of interest. For example, readings from a VIS spectroscope, i.e. a spectroscope that senses visible light, may be used to determine the color of the object. Similarly, readings from a NIR spectroscope, i.e. a spectroscope that senses near-infrared electromagnetic radiation, may be used to determine, for example, what material the object to be recycled is made of.

[0006] However, further properties of the object need to be determined. Summary of the Invention

[0007] In view of the above, it is an object of the present invention to provide an apparatus for classification of objects, which makes it possible to determine other characteristics than the color and / or NIR spectrum of objects in a stream.

[0008] Another object is to provide such a device for classification of objects which allows the determination of not only the color and / or NIR spectrum of the objects in the stream, but also further properties of the objects.

[0009] Another object is to provide such an apparatus that allows for enhanced sorting of objects.

[0010] In order to achieve at least one of the above objects, as well as other objects that will become apparent from the following description, the present invention provides an apparatus having the characteristics defined in claim 1. Preferred variants of the apparatus will become apparent from the dependent claims.

[0011] More specifically, according to a first aspect, there is provided an apparatus for classifying an object into one of at least a first class and a second class, the apparatus comprising: Irradiation arrangement; A scanning element; A spectroscopic system; Equipped with the illumination arrangement is adapted to emit at least one illumination beam comprising optical radiation, the illumination beam configured to cause a photoexcitation event in the photoresponsive portion of the object upon illumination of the photoresponsive portion of the object by the at least one illumination beam; the illumination arrangement further comprises a first optical arrangement adapted to direct and optionally focus the at least one illumination beam towards the scanning element for at least a first time period; the scanning element is configured to redirect the at least one illumination beam along the illumination direction towards the object passing zone such that the object is illuminated by the at least one illumination beam in the illuminated area for at least a first period of time when the object is transported on the conveyor belt or when the object is free falling through the object passing zone, for example at a speed between 0.4 m / s and 20 m / s, The first optical arrangement is further, optionally, configured to focus the at least one illumination beam within or near an object pass zone; The spectroscopic system comprises a sensor arrangement comprising one or more sensors, the sensor arrangement being adapted to receive and analyze optical radiation reflected, scattered and / or emitted by an object in at least one of a plurality of inspection zones sequentially arranged in a first direction; a first inspection zone of the plurality of inspection zones substantially coincides with the illuminated area for a first period of time; a second inspection zone of the plurality of inspection zones is disposed after the first inspection zone with respect to the first direction; a third inspection zone of the plurality of inspection zones is disposed after the second inspection zone with respect to the first direction; and, the scanning element is further adapted to shift the plurality of inspection zones and the illumination direction in a first direction relative to the object, whereby the second inspection zones substantially coincide with the first inspection zones prior to the shift for a second period of time after the first period of time; the scanning element is further adapted to shift the plurality of inspection zones and the illuminated area in a first direction relative to the object, whereby the third inspection zone substantially coincides with the second inspection zone prior to the shift for a third time period after the second time period; The spectroscopic system further includes an optical element, the optical element being configured to: optical radiation emitted by objects in the second inspection zone during a second time period, the optical radiation being related to phosphorescence events resulting from photoexcitation events in the first inspection zone during the first time period; and optical radiation emitted by an object in the third inspection zone during a third time period, the optical radiation being related to a phosphorescence event resulting from a photoexcitation event in the first inspection zone during the first time period; and and configured to receive configured to redirect the received optical radiation to at least one of the one or more sensors; The sensor arrangement is further a second zone collection function configured to collect second zone data based on at least one sensor signal from one or more sensors, the at least one sensor signal relating to optical radiation emitted by objects in the second inspection zone; and a third zone collection function configured to collect third zone data based on at least one sensor signal from one or more sensors, the at least one sensor signal relating to optical radiation emitted by objects in the third inspection zone; a classification function configured to classify the object based on the second zone data and the third zone data; an output function configured to output a classification signal that assigns one of at least a first class and a second class to the object based on an output of the classification function; The method includes processing circuitry configured to perform the steps of:

[0012] According to a second aspect, there is provided a method for classifying objects to be transported in mass transit into one of at least a first class and a second class, the method comprising: Emitting and directing at least one illumination beam comprising optical radiation towards an object passage zone; illuminating an illuminated area of ​​an object with the at least one illumination beam at least at a first time and for at least a first period of time, the object being transported on a conveyor belt or free falling at a speed between 0.4 m / s and 20 m / s in an object passing zone, thereby causing a photoexcitation event in a photoresponsive portion of the object; directing optical radiation via a scanning element towards one or more sensors of the sensor arrangement, the optical radiation being scattered and / or emitted by the object in at least one of a plurality of inspection zones arranged sequentially in a first direction, a first inspection zone of the plurality of inspection zones substantially coinciding with the illuminated area, and a second inspection zone of the plurality of inspection zones being arranged after the first inspection zone with respect to the first direction; shifting the plurality of inspection zones and the illuminated area in a first direction relative to the object by the scanning element such that a second inspection zone at a second time after the first period of time substantially coincides with the first inspection zone at the first time; thereafter, receiving, with the sensor arrangement, optical radiation emitted by the objects in the second inspection zone during a second time period, the optical radiation emitted by the objects in the second inspection zone relating to phosphorescence events resulting from the photoexcitation events; collecting first phosphorescence data related to received light emitted by objects within the second inspection zone during a second time period; shifting the plurality of inspection zones and the illuminated area in a first direction relative to the object by the scanning element such that a third inspection zone at a third time point after the second time period substantially coincides with the second inspection zone at the second time point; thereafter, receiving, with the sensor arrangement, optical radiation emitted by objects within a third inspection zone during a third time period, the optical radiation emitted by the objects within the third inspection zone relating to phosphorescence events resulting from the photoexcitation events; collecting second phosphorescence data related to received light emitted by objects within the third inspection zone during a third time period; and classifying, by a processing circuit, the object based on the second zone data and the third zone data; outputting, by the processing circuitry, a classification signal that assigns one of at least a first class and a second class to the object based on the results of the classifying; Equipped with.

[0013] The information provided below is applicable to both the first and second aspects described above.

[0014] The first and second aspects provide for combined detection of fluorescence and phosphorescence: characteristics of the fluorescence and / or phosphorescence spectra, such as rise time, decay time, e.g., reaction time of color pigments, one or more slopes of the respective spectra, or the time between them, can be determined, and one or more of these characteristics can be used to determine the characteristics of the passing object.

[0015] According to one exemplary embodiment, the device comprises a point illumination that is scanned over the first object passing zone. This allows lower costs when sweeping illumination over a surface compared to non-scanning solutions, and therefore requires a lower total intensity as well as a smaller number of illumination sources. When the illumination emits light radiation in the UV wavelength range, a smaller number of illumination sources is also advantageous, as it provides a safer system with less or no need for shielding.

[0016] According to one exemplary embodiment, the number of inspection zones is at least n, and each reflective surface of the scanning element shifts the inspection zone exactly or at least n times, where n is a positive integer, before the illumination direction is redirected to the first illumination direction. After the illumination direction is redirected to the first illumination direction, the shifts are preferably repeated n times and further data is collected.

[0017] According to one exemplary embodiment, the scanning element is a polygon mirror configured to rotate in a first direction about a rotation axis, the polygon mirror comprising a set of reflective surfaces arranged one after the other around the rotation axis. The rotation of the polygon mirror is preferably continuous and preferably at a substantially constant speed. Also, each reflective surface of the set of reflective surfaces is preferably configured to receive optical radiation from the first, second and third inspection zones during at least a respective corresponding one of three successive periods. Additionally or alternatively, each reflective surface of the set of reflective surfaces is preferably configured to receive optical radiation from the second to nth inspection zones during a respective corresponding one of at least n successive periods.

[0018] After being redirected by the scanning element, each of the at least one illumination beam may be a beam of parallel light rays or a beam of non-parallel light rays, such as a diverging beam or a converging beam, and / or the cross-section of the illumination beam may be circular, round, or strip-shaped, to name a few non-limiting examples.

[0019] One redirection of the illumination beam from a first position to an nth position by the scanning element is referred to as one scan by the scanning element. Thus, in the case of a polygon mirror having m reflective surfaces, one rotation of the polygon mirror preferably corresponds to m performances of the second and third collection functions, one for each reflective surface.

[0020] The classification function may be performed once per scan of the scanning element, once per revolution of the polygon mirror or at predefined fixed or variable time intervals. The classification function may for example be performed based on data from the first inspection zone and / or based on data from the second to nth inspection zones and / or from any other sensor input, such as based on image processing of the object stream, which image processing is for example performed based on camera or spectrometer images of the object stream.

[0021] The second zone data, the third zone data, and preferably further zone data (e.g., the fourth zone data through the nth zone data), and optionally the first zone data, are preferably repeatedly collected as the scanning element repeatedly redirects the illumination direction from the first position to the nth position. By way of example, data from the second inspection zone may be repeatedly collected as the scanning element repeatedly scans the object passage zone, and may be collected once, twice, or multiple times per scan.

[0022] According to one exemplary embodiment, an inspection zone preceding a first inspection zone in a first direction may be used as a reference area for ambient light calibration or as an ambient light calibration, wherein the first inspection zone is disposed between the preceding inspection zone in the first direction and the second inspection zone.

[0023] According to one exemplary embodiment, specular reflection and fluorescence events of the illumination beam are measured by only the first inspection zone, and optionally the optical radiation received from this inspection zone may be converted into a digital representation of the associated spectrum, although further inspection zones, for example both the first and second inspection zones, may be used to measure specular reflection and / or fluorescence events and optionally convert this into a digital spectrum.

[0024] According to an exemplary embodiment, one or more phosphorus events are measured using inspection zones 1 through n, or 2 through n, and optionally the optical radiation received from these zones may be converted into a digital representation of the associated phosphorus event spectrum.

[0025] Additionally or alternatively, the intensity of the specular reflection of the illumination beam after it is received by the scanning element may be used to create a representation of the object passing therethrough as a greyscale image.

[0026] In the context of the present invention, the term "objects" is to be understood as objects, e.g. apples, rice grains, rocks, minerals, and waste objects, e.g. plastic waste, including used containers. Objects may also comprise slices of objects, such as parts or slices of objects, e.g. waste objects, including used containers. Objects may also include signs or markers, e.g. provided to the object during or after the manufacture of the object, or provided to a part of the object if the object is divided into at least two pieces. The flow of objects consists of individual object pieces, which are inspected and preferably sorted.

[0027] The footprint of the object, i.e. the area occupied by each piece of the object when placed on the horizontal conveyor belt, may be in the range of 1-10 mm2 and / or 10-100 mm2 and / or 1-100 mm2 and / or 10-1000 mm2 and / or 1-100 cm2 and / or 40-400 cm2 and / or 10-1000 cm2 and / or 1-100 dm2. According to one example, the individual object pieces are separated from one another or at least only partially overlap in a plane parallel to the direction of transport (or free fall).

[0028] In the context of the present invention, the term "classify" or "classification" should be understood as assigning at least one class to an object based at least on the spectral response of the object. This class is used by the sorting system when directing the object piece towards at least one of the available destinations, based on characteristics such as the color, material, quality, marking, etc. of the object piece and / or a combination of these characteristics. The classes may be numbers representing the value of this characteristic, such as red, green, yellow; oil, plastic, glass, textile, wood; mature, rot, deteriorated; food container, non-food container, etc. Also the sorting classes may be rejected, possibly rejected and need further inspection, possibly acceptable and need further inspection, acceptable.

[0029] According to one example, the system is configured to classify pieces in the stream of objects based on their individual phosphorus responses or characteristics of their phosphorus responses, where in the context of the present invention the term phosphorus response characteristics is a property of the emitted phosphorus spectrum, such as the duration, rise time, decay time and / or intensity, or a predefined wavelength range of the emitted phosphorus spectrum.

[0030] Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength than the absorbed radiation, and therefore a lower photon energy. Perceptible instances of fluorescence occur when the absorbed radiation is in the ultraviolet region of the spectrum (invisible to the human eye), while the emitted light is in the visible region. Fluorescent materials stop glowing almost immediately when the radiation source is stopped, unlike phosphorescent materials, which continue to emit light for some time afterwards.

[0031] Phosphorescence is a type of photoluminescence related to fluorescence. When exposed to shorter wavelength light (radiation), phosphorescent materials glow, absorb light, and re-emit it at a longer wavelength. Unlike fluorescence, phosphorescent materials do not immediately re-emit the radiation they absorb. Instead, phosphorescent materials absorb some of the radiant energy and re-emit it over a much longer period of time after the radiation source is removed.

[0032] There are two distinct mechanisms that can produce phosphorescence, called triplet phosphorescence and persistent phosphorescence. Persistent phosphorescence occurs when a high-energy photon is absorbed by an atom and its electron is trapped by a defect in the lattice of a crystalline or amorphous material. A defect such as a missing atom (vacancy defect) can trap an electron like a pit and store the electron's energy until it is released by a random spike of thermal (vibrational) energy. Such materials then emit light that gradually decreases in intensity over a period ranging from a few seconds to a few hours after the initial excitation.

[0033] In triplet phosphorescence, an electron that absorbs a photon (energy) undergoes an unusual intersystem crossing to an energy state of different (usually higher) spin multiplicity, usually a triplet state. As a result, the excited electron can become trapped in the triplet state, with only "forbidden" transitions available to return to the lower energy singlet state. Although such transitions are "forbidden," they still occur quantum mechanically, but are kinetically unfavorable and therefore proceed on a significantly slower time scale. Most phosphorescent compounds are still relatively fast emitters, with triplet decay times on the order of milliseconds.

[0034] The objects to be sorted are provided as a stream of objects, and the device illuminates the objects to be sorted with optical radiation, for example in the UV wavelength range designed to induce a phosphorescence response from the illuminated objects. Because the stream of objects is moving and there is a delay before phosphorescence occurs, it is difficult to determine the spectrum, particularly the rise time and decay time, with a high degree of accuracy.

[0035] The objects to be classified are provided as a stream of objects, partially or exclusively containing objects with known phosphorus response characteristics. When the stream of objects contains only objects with known phosphorus response characteristics, each individual object piece has a known phosphorus response characteristic or a known phosphorus response characteristic above or below one or more given thresholds. When the stream of objects contains partially objects with known phosphorus response characteristics, the stream may also include objects that have no phosphorus response at all or may also include objects with unknown phosphorus response characteristics to the irradiated light radiation. The part of the stream that has a phosphorus response to the irradiated light radiation may be referred to as the light-responsive part of the object.

[0036] The present invention is based on an insight by the inventors into how a system should be designed to induce and detect the phosphorus response, and optionally also the fluorescent response and / or color spectrum and / or NIR spectrum, of objects in a stream as the objects move in free fall or are transported by a conveyor.

[0037] According to one exemplary embodiment, the aforementioned device or method further comprises receiving, at one or more sensors of the sensor arrangement during at least a first time period, optical radiation reflected, scattered and / or emitted by objects in the first inspection zone, wherein the optical radiation reflected and / or scattered by the objects in the first inspection zone relates to the at least one illumination beam and the optical radiation emitted by the objects in the first inspection zone relates to fluorescence events resulting from the optical excitation events; collecting first zone data relating to received optical radiation reflected, scattered, and / or emitted by objects within a first examination area during at least a first time period; Equipped with.

[0038] Optical information about the object may be gathered by detecting and collecting, once or repeatedly, radiation from the first detection zone during one, two or all of the first, second and third time intervals, and possibly further time intervals.

[0039] According to one exemplary embodiment, data from a first inspection zone is collected during one or more scans by the scanning element, this first zone data being a representation of at least a first spectrum, and classifying the object comprises determining a wavelength distribution of the first spectrum and, optionally, determining at least one characteristic related to the shape of the first spectrum, such as peak height, peak width, and / or peak area of ​​one or more peaks.

[0040] According to one exemplary embodiment, data from the second and third inspection zones and optionally the fourth to nth inspection zones are collected sequentially during one or several scans by the scanning element, preferably by the second and third collection functions and optionally the fourth to nth collection functions, and the second to third zone data or the second to nth zone data is a representation of at least one phosphorus event spectrum, and classifying the object comprises determining a wavelength distribution of the one phosphorus event spectrum based on the collected data, and optionally determining at least one characteristic related to the shape of the phosphorus event spectrum, such as a peak height, a peak width, and / or a peak area of ​​one or more peaks based on the collected data.

[0041] According to one exemplary embodiment, the second and third collection functions and optionally the fourth through nth collection functions are configured to form phosphor data based on at least the second zone data and the third zone data, the phosphor data being a representation of at least a phosphorescence spectrum, and classifying the object comprises determining a wavelength distribution of the phosphorescence spectrum and, optionally, determining at least one characteristic related to the shape of the second spectrum, such as a peak height, a peak width, and / or a peak area of ​​one or more peaks.

[0042] According to one exemplary embodiment, classifying the object comprises determining the rise time and / or decay time of one or both of the phosphorescent and fluorescent events.

[0043] The type of object can be determined by analyzing a characteristic associated with one or both of the phosphorescent and fluorescent events. The characteristic can be compared to, for example, one, two, or all of a threshold, a lookup table, and a criterion.

[0044] According to one exemplary embodiment, classifying the object includes: At least one characteristic related to a phosphorescence event of the object; and at least one characteristic related to a respective one of the object's color, transmittance, reflectance, and fluorescence; Classifying the object based on

[0045] According to one exemplary embodiment, classifying the object further comprises comparing at least one property related to the phosphorescence of the object, as well as one or more other properties related to a corresponding one of the color, transmittance, reflectance, and fluorescence of the object, to data stored in a local or centralized database.

[0046] According to one exemplary embodiment, the classifying comprises: determining whether the object is provided with phosphorus markers by at least one of image processing and spectral processing; and / or Identifying, for example by spectral processing, one or more materials that make up the object; and / or Determining the materials that make up a single piece of material and determining whether the combination of these materials is acceptable or unacceptable Equipped with.

[0047] The phosphorus markers may be identified, for example, based on their shape and their profile may be identified by image processing. Additionally or alternatively, the phosphorus markers may be identified, for example, based on the spectrum or spectral signature that they emit in response to being illuminated by an illumination beam. The spectral signature may be identified by spectral processing.

[0048] According to one exemplary embodiment, the at least one illumination beam that causes the photoexcitation events comprises optical radiation in the ultraviolet and / or visible wavelength range. The at least one illumination beam may comprise optical radiation in one or a combination of the ultraviolet, visible, near infrared, and infrared wavelength ranges.

[0049] According to one exemplary embodiment, receiving optical radiation reflected, scattered, and / or emitted by objects in the first inspection zone comprises receiving optical radiation within one or a combination of ultraviolet, visible, near infrared, and infrared wavelength ranges.

[0050] According to one exemplary embodiment, the sensor arrangement comprises at least a first sensor configured to detect optical radiation in the ultraviolet and / or visible wavelength range and a second sensor configured to detect optical radiation in the near infrared and / or infrared wavelength range.

[0051] According to one exemplary embodiment, the scanning element and the optical element are further configured to receive and redirect optical radiation from at least the second and third inspection zones towards the sensor arrangement simultaneously during at least the second and third time intervals; The sensor arrangement preferably comprises at least one sensor array, each of the at least one sensor array having a plurality of sensor pixels, and the at least one sensor array is arranged such that optical radiation reflected, scattered and / or emitted by objects in the respective inspection zones is received on a respective set of corresponding sensor pixels of the at least one sensor array, the pixels of the respective corresponding set of sensor pixels being different or only partially overlapping.

[0052] The inventors have realised that by using interleaved readings of the sensor, where different sets of pixels are used to detect phosphorescence responses at different times from the same portion of the object and adjacent pixels are used to detect phosphorescence responses at the same time from adjacent portions of the object, a highly accurate phosphorescence spectrum can be determined along with its rise and decay times even though the object is moving in free fall at high speed or transported by a conveyor.

[0053] The above sensor readings correspond to the collection of zone data by the second zone collection function through the nth zone collection function.

[0054] According to one exemplary embodiment, the optical element further includes a scanning element. light radiation relating to at least one illumination beam reflected and / or scattered by an object in a first inspection zone during a first time period, and / or during a first time period, light radiation emitted by the object associated with a fluorescence event resulting from a light excitation event in the first examination zone. is configured to receive The processing circuitry further comprises: a first zone collection function configured to collect first zone data based on at least one sensor signal from one or more sensors, the sensor signal relating to optical radiation reflected, scattered, and / or emitted by objects in the first inspection zone; is configured to run The classification function is further configured to classify the object based also on the first zone data.

[0055] The flow of objects may comprise pieces of objects that do not exhibit fluorescent or phosphorescent events when illuminated with at least one illumination beam. Such pieces of objects are considered not to be photoresponsive in the context of the present invention. The flow of objects may comprise pieces of objects that exhibit fluorescent and / or phosphorescent events when illuminated with at least one illumination beam, which fluorescent and / or phosphorescent events are preferably strong enough to be detected and determined by at least one sensor. Such pieces of objects are considered to be photoresponsive in the context of the present invention. Portions of objects that exhibit detectable fluorescent events when illuminated with at least one illumination beam are referred to as fluorescent portions. Portions of objects that exhibit detectable phosphorescent events when illuminated with at least one illumination beam are referred to as phosphorescent portions.

[0056] According to one exemplary embodiment, the fluorescent portion of the light-responsive portion of the object emits light radiation upon illumination with at least one illumination beam in a first zone, the light radiation being associated with a fluorescent event and comprising light radiation within one or more wavelength bands, and each piece of the object of the fluorescent portion of the light-responsive portion of the object emits radiation within at least one of the one or more wavelength bands upon illumination with the at least one illumination beam; at least one illumination beam is substantially free of optical radiation within one or more wavelength bands; Optionally, the at least one illumination beam is comprised of optical radiation within at least one low wavelength range and at least one high wavelength range, and each of the one or more wavelength bands is optionally comprised of optical radiation within a wavelength range different from both the low wavelength range and the high wavelength range.

[0057] As described further herein, the above embodiments facilitate detection of radiation associated with a fluorescent event because they allow the radiation to be detected without being swamped by reflected or scattered radiation. This is possible because a fluorescent event contains one or more unique wavelengths that are not present in at least one illumination beam.

[0058] According to one exemplary embodiment, the sensor arrangement comprises a first sensor and a first diffractive element, and a second sensor and a second diffractive element, and the optical element comprises: directing optical radiation within a first wavelength range to only a first grating of the first and second gratings and to only a first sensor of the first and second sensors; Directing optical radiation within a second wavelength range to only the second diffraction grating of the first and second diffraction gratings and to only the second sensor of the first and second sensors. It is structured as follows: The first and second wavelength ranges may be the same, different, or only partially overlapping.

[0059] When the first and second wavelength ranges are the same, the radiation is split, for example by a beam splitter that directs half the intensity of all wavelengths in one direction and the other half of the intensity of all wavelengths in another direction.

[0060] When the first and second wavelength ranges are different, the radiation is split, for example, by a beam splitter that directs substantially all of the UV and VIS light intensity in one direction and the NIR light in another direction.

[0061] When the first and second wavelength ranges partially overlap, the radiation is split, for example by a beam splitter that directs substantially all of the UV intensity and half the VIS light intensity in one direction and the other half of the VIS light intensity and all of the NIR light intensity in another direction.

[0062] According to one exemplary embodiment, the sensor arrangement comprises a first sensor, and the optical element comprises: directing optical radiation within a first wavelength range to a first sensor for a period of time; Directing optical radiation within a second wavelength range to a second sensor for another period of time. It is structured as follows: The first and second wavelength ranges may be different or may only partially overlap.

[0063] According to one exemplary embodiment, the illumination arrangement comprises at least two illumination arrangements, the optical axes of which are incident on the scanning element from different directions, each of the at least two illumination arrangements adapted to emit optical radiation in different or only partially overlapping wavelength ranges, the optical radiation in the different or only partially overlapping wavelength ranges being emitted simultaneously or sequentially, the different directions being preferably non-parallel.

[0064] According to one exemplary embodiment, the illumination arrangement comprises at least one illumination arrangement adapted to emit optical radiation in different or only partially overlapping wavelength ranges at different times.

[0065] By providing at least two illumination arrangements, a stronger illumination can be provided in the first detection zone. Also, the illumination of the first detection zone can be easily adjusted by using different types of illumination sources or light sources with different characteristics as the first and second illumination arrangements. Furthermore, a more robust device can be achieved. The device may not have to be taken out of operation in case of failure of one of the first and second illumination sources, and therefore can still operate during replacement of one of the illumination sources.

[0066] The focusing arrangement may comprise a first focusing element adapted to direct and focus the first set of illumination beams onto the scanning element and a second focusing element adapted to direct and focus the second set of illumination beams onto the scanning element, which is advantageous in that the first and second sets of illumination beams may be individually directed and focused onto the scanning element. The focusing element may be any optical element capable of focusing and directing the first and / or second sets of illumination beams. The focusing element may be a combination of multiple optical elements acting together. The focusing element may direct the first and / or second sets of illumination beams along the incident illumination direction of the first and / or second sets of illumination beams. The first focusing element may be a lens or a mirror. The first focusing element may be a combination of a lens and a mirror. The second focusing element may be a combination of a lens and a mirror. The second focusing element may be a combination of a lens and a mirror.

[0067] The illumination source arrangement may comprise a single illumination source or light source adapted to emit the first set of illumination beams and the second set of illumination beams, which is advantageous in that the illumination source arrangement may be made more energy efficient and the light source arrangement may be made more compact, since only space needs to be allocated to a single illumination source.

[0068] According to one exemplary embodiment, each of the one or more sensors comprises a sensor array having a plurality of sensor pixels arranged such that optical radiation reflected, scattered and / or emitted by an object in a second inspection zone is received on a second set of sensor pixels of the sensor array, and such that optical radiation emitted by an object in a third inspection zone is simultaneously received on a third set of sensor pixels of the sensor array, the pixels of the first and second sets of sensor pixels being different or only partially identical.

[0069] Optionally, the plurality of sensor pixels are arranged such that optical radiation emitted by an object in the first inspection zone is received on a first set of sensor pixels of the sensor array, the pixels of the first set of pixels being different from or only partially overlapping with the first and second sets of sensor pixels.

[0070] According to one exemplary embodiment, the apparatus comprises a further sensor arrangement adapted to receive and analyze optical radiation reflected and / or scattered by objects in the illuminated area, and the processing circuitry is optionally further configured to perform an additional collection function configured to collect additional data based on an additional sensor signal from the further sensor arrangement, the additional sensor signal relating to optical radiation reflected and / or scattered by objects in the illuminated area.

[0071] The scanning arrangement is preferably calibrated using a white reference or white light. The apparatus optionally comprises a reference arrangement comprising a white reference element, which is adapted to receive the optical radiation from the illumination arrangement and to direct the received optical radiation towards the detector system via the white reference element. The white reference element is a reference that reflects or transmits a substantially uniform spectrum within one or more predetermined wavelength intervals of interest. For example, if all wavelengths within the visible spectrum are of interest, the white reference element will reflect or transmit light that is perceived as white when illuminated by a light source that emits a uniform spectrum across the entire visible wavelength range. However, if only or additionally wavelengths in the NIR spectrum are of interest, the white reference element will reflect or transmit optical radiation with a substantially uniform intensity when illuminated by a light source that emits a uniform spectrum across the NIR wavelength range of interest.

[0072] In addition to or instead of the spectrometer, a camera-based sensor system may be used, i.e. a sensor system without a diffractive element for splitting the optical radiation into different wavelength bands. The camera-based sensor system may comprise a CCD or CMOS camera with one or more sensor matrices or arrays for detecting all the radiation or for example for detecting red, green and blue separately. The sensor array or matrix of the camera-based sensor system may be used to detect the intensity of the radiation reflected, scattered and / or emitted from the 1st to nth inspection zones as described above. The acquisition of the camera system may be synchronized with the polygon mirror used for the optical projection.

[0073] Additionally or alternatively, the camera-based sensor system may be used as part of a laser triangulation system. According to one exemplary embodiment, the device comprises a laser triangulation system. The laser triangulation system includes a laser arrangement adapted to emit a laser beam toward a second detection zone through which the object is provided. The laser arrangement typically includes one or more laser light sources and, optionally, an optical element for forming the emitted laser light into a laser beam.

[0074] It should be noted that within the context of this application, the term laser beam can be any type of laser light, visible or invisible, that has an elongated extension, such that when it strikes a surface, the light forms a line or line-like profile.

[0075] The laser triangulation system includes a camera-based sensor arrangement configured to receive and analyze light reflected and / or scattered by objects within the first object pass zone or the second object pass zone.

[0076] The first and second detection zones may overlap, which is advantageous in that it may be easier to correlate an object in the first detection zone with a corresponding object in the second detection zone. In other words, it may be easier to determine when a particular piece of object that passed through the first detection zone passes through the second detection zone. This configuration is advantageous when an object moves through the first and / or second detection zone in a random manner, as is typically the case when an object free-falls or slides through the first and / or second detection zone.

[0077] The first and second detection zones may partially overlap, the first and second detection zones may almost completely overlap, and thus the first and second detection zones may be located in substantially the same physical location.

[0078] According to one embodiment, the received light of the spectroscopic system is fully or partially intersected with the received light of the camera-based sensor arrangement and / or the laser beam. The special provision of the spectroscopic system in relation to the camera-based sensor arrangement and / or the laser arrangement allows for a compact system requiring significantly less space.

[0079] According to one example, the optical radiation received by the spectroscopic system from the first object passage zone completely or partially intersects or crosses the light received by the camera-based sensor arrangement, i.e. light originating from the laser beam and reflected and / or scattered by an object in the first or second detection zone.

[0080] According to one example, an object transported through a first object passing zone is also transported through a second object passing zone. This allows a particular object provided to a first object passing zone to be correlated to be the same object when provided later or in parallel through a second object passing zone. In effect, the same object will typically be analyzed by both the spectroscopic system and the laser triangulation system, either sequentially or in parallel. Thus, a compact device with enhanced detection capabilities is provided.

[0081] According to one example, the device further includes one, two or more optical filters arranged in the light path from the one or more illumination sources through the first detection zone to at least one sensor of the spectrometer system. The one, two or more optical filters prevent light originating from the first set of light beams and the second set of light beams from reaching the camera-based sensor arrangement. This arrangement of the one, two or more optical filters can form preventing undesired light from reaching the camera-based sensor system or the spectrometer system that would otherwise risk interfering with them. Providing one, two or more is particularly relevant and therefore advantageous when the first and second detection zones overlap. According to one example, at least one of the optical filters prevents the passage of light originating from the first set of light beams, the second set of light beams and ambient light, while allowing the passage of light originating from the laser light.

[0082] The apparatus may further comprise a processing unit coupled to the spectroscopic system and the camera-based sensor arrangement, the processing unit configured to determine a first set of characteristics for the object in the first detection zone based on the output signal of the spectroscopic system, and the processing unit configured to determine a second set of characteristics for the object in the second detection zone based on the output signal of the camera-based sensor arrangement. Providing a processing unit coupled to the spectroscopic system and the camera-based sensor arrangement enables the processing unit to determine a plurality of or one characteristics of the object in each of the first and second detection zones. Thus, the processing unit may receive signals from the spectroscopic system and the camera-based sensor arrangement, respectively. The received signals may be based on an analysis of light received by the spectroscopic system and the camera-based sensor arrangement, respectively.

[0083] It should be noted that within the context of this application, the term processing unit may be any unit, system, or device capable of receiving one or more signals or data from other entities and processing the received signals or data. Processing may include, for example, calculating multiple or one characteristics based on the received signals or data, forwarding the received signals or data, and modifying the received signals or data. The processing unit may be a single unit or may be distributed across multiple devices, such as multiple PCs, each with processing capabilities. The processing unit may be implemented in hardware or software.

[0084] It should be noted that within the context of this application, the term property set may be any set of data including any type of data. A property set may include any number of properties, including zero. Thus, a property set may be an empty set, which may indicate, for example, the absence of an object.

[0085] The first set of characteristics may be indicative of at least one of a spectral response of the object, a material type of the object, a color of the object, fluorescence of the object, phosphorescence of the object, maturity of the object, dry object content of the object, water content of the object, fat content of the object, oil content of the object, heat value of the object, presence of bones or fish bones in the object, presence of pests, mineral type of the object, ore type of the object, defect level of the object, detection of hazardous biological material in the object, presence of the object, absence of the object, detection of multi-layer material in the object, detection of fluorescent and / or phosphorescent markers in the object, color markers of the object, quality grade of the object, physical structure of the surface of the object, and molecular structure of the object.

[0086] One example of a relevant harmful biological material that can be detected is mycotoxins.

[0087] The above features of the first feature set may be determined in certain combinations that may be useful for detecting objects in the first detection zone. Examples of applications where such combinations are useful are pet food sorting, fish bone detection in fillets, paper sorting using visible and NIR spectroscopy, removal of foreign material and shells from pistachios, polymer recycling, to name a few non-limiting examples.

[0088] The second set of characteristics may be indicative of at least one of the following: height of the object, height profile of the object, a 3D map of the object, intensity profile of reflected and / or scattered light, center of volume of the object, estimated center of mass of the object, estimated weight of the object, estimated material of the object, presence of the object, absence of the object, detection of isotropic and anisotropic light scattering of the object, wood structure and quality, surface roughness and texture of the object, and an indication of the presence of fluid in the object.

[0089] Examples of relevant fluids are the oil and water in food products.

[0090] The above features of the second feature set may be determined in particular combinations that may be useful for detecting objects in the second detection zone. Examples of applications in which such combinations are useful are glass sorting and quartz sorting, to name a few non-limiting examples.

[0091] The processing unit may further be configured to receive an input indicative of a viewing angle of the camera-based sensor arrangement relative to the second detection zone and to compensate for the viewing angle of the camera-based sensor arrangement when determining the second set of characteristics, which is advantageous in that a more accurate subsequent sorting or ejection of the object may be achieved. In fact, the height of the object in the second detection zone may be compensated for when determining the position of the object in the second detection zone. This allows the subsequent sorting or ejection operation to act or affect the object at a location to prevent an unjustified sorting or ejection. For example, the sorter or ejector may impact the object at its estimated center of mass, thereby reducing the risk of, for example, slipping or rolling of the object. The ejector may be configured with a valve image processing step to reduce or minimize compressed air and energy consumption while maintaining optimal sorting yield and sorting losses.

[0092] The processing unit may be configured to receive an input indicative of a geometry of a laser arrangement and a camera-based sensor arrangement relative to the second detection zone.

[0093] The processing unit may be configured to compensate for a geometry of the laser arrangement and the camera-based sensor arrangement relative to the second detection zone when determining the second set of characteristics.

[0094] The apparatus may further comprise a discharge arrangement coupled to the processing unit, the discharge arrangement adapted to discharge and sort the objects into a plurality of fragments in response to receiving a signal from the processing unit based on the determined first set of characteristics and / or the determined second set of characteristics, the discharge arrangement adapted to discharge and sort the objects by at least one of a jet of compressed air, a jet of pressurized water, a mechanical finger, a bar of jets of compressed air, a bar of jets of pressurized water, a bar of mechanical fingers, a robotic arm, and a mechanical diverter.

[0095] By providing a ejection arrangement coupled to the processing unit, the apparatus may eject and thus sort the object into a plurality of pieces based on the determined first set of characteristics and / or the determined second set of characteristics. Thus, the object may be sorted based on the analysis performed by the spectroscopic system and / or the laser triangulation system.

[0096] The multiple fragments may be based on any of the determined characteristics. The fragments may be based on material or color, for example. A fragment may represent an object that should be discarded or scrapped.

[0097] The ejection and sorting may be performed by compressed air jets, pressurized water jets, mechanical fingers, a bar of compressed air jets, a bar of pressurized water jets, a bar of mechanical fingers, a robotic arm, or a mechanical diverter.

[0098] Alternatively, to be rejected and sorted, the objects may be analyzed online, for example by a cloud service. Objects so analyzed may then be classified, for example with respect to purity, defect level, average color, etc.

[0099] The apparatus may further comprise a conveyor for transporting objects through the first and second detection zones, or a chute, optionally including a vibratory feeder, for sliding or free-falling objects through the first and / or second detection zones.

[0100] By providing a conveyor, objects can be transported through the first and second detection zones in a controlled manner. Objects transported through and analyzed in the first detection zone can then be transported through and analyzed in the second detection zone. By controlled transport of objects through the first and second detection zones, the objects can be kept track of. Thus, objects in the first detection zone can be correlated or identified as being the same as objects in the second detection zone.

[0101] By providing a chute, optionally including a vibratory feeder, an object may be slid or allowed to free fall through the first and / or second detection zone. An object may be slid through the first and second detection zones. An object may be allowed to free fall through the first and second detection zones. An object may be slid through the first detection zone and allowed to free fall through the second detection zone. The provision of a chute, optionally including a vibratory feeder, is advantageous for small bulk objects, such as different types of grains.

[0102] Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. It should be understood, however, that the detailed description and specific examples, while indicating preferred variations of the inventive concept, are given by way of example only, since various changes and modifications within the scope of the inventive concept will become apparent to those skilled in the art from this detailed description.

[0103] Thus, it should be understood that the inventive concept is not limited to the specific components of the device described, as such devices may vary. It should also be understood that the terminology used herein is for the purpose of describing the particular variant only, and is not intended to be limiting. It should be noted that, as used in this specification and the appended claims, the articles "a," "an," "the," and "said" are intended to mean that there is one or more of the element, unless the context clearly dictates otherwise. Thus, for example, reference to "a unit" or "the unit" may include several devices, etc. Also, the terms "comprising," "including," "containing," and similar expressions do not exclude other elements. Moreover, items or arrangements described as part of a whole may also be used alone by themselves. [Brief description of the drawings]

[0104] [Figure 1]1 shows a schematic diagram of an apparatus 100 for classification of an object 102 according to the present disclosure. [Diagram 2] 2 shows a schematic diagram of some of the components inside the housing 110 shown in FIG. 1. [Diagram 3] 2 shows a schematic diagram of some of the components inside the housing 110 shown in FIG. 1. [Figure 4] A schematic diagram of some of the components in the spectroscopic system 120 of the apparatus is shown. [Figure 5a] 1 is a top view of a piece of material on a conveyor belt (not shown). [Figure 5b] 1 is a top view of a piece of material on a conveyor belt (not shown). [Figure 5c] 1 is a top view of a piece of material on a conveyor belt (not shown). [Figure 6] 1 shows a graphical representation of intensity data from a material that emits both fluorescence and phosphorescence. [Figure 7a] 4 shows intensity data of detected radiation when the illuminated object is a white piece of paper. [Figure 7b] 4 shows intensity data of detected radiation when the illuminated object is a white piece of paper. [Figure 8a] 4 shows intensity data of detected radiation when the illuminated object is a yellow glowing bottle. [Figure 8b] 4 shows intensity data of detected radiation when the illuminated object is a yellow glowing bottle. [Figure 9a] 4 shows intensity data of detected radiation when the illuminated object is a blue marker. [Figure 9b] 4 shows intensity data of detected radiation when the illuminated object is a blue marker. [Figure 10a] 4 shows intensity data of detected radiation when the illuminated object is a red marker. [Figure 10b] 4 shows intensity data of detected radiation when the illuminated object is a red marker. [Figure 11]Detected radiation intensity data for four different materials is shown. [Figure 12] Average intensity data across several experiments for white paper is shown. [Figure 13] Average intensity data across several experiments for yellow glowing bottles is shown. [Figure 14] Average intensity data across several experiments for blue markers is shown. [Figure 15] Average intensity data across several experiments for the red markers is shown. [Figure 16] The maximum intensity recorded across all wavelengths as a function of time for white paper is shown. [Figure 17] The red marker shows the maximum intensity recorded across all wavelengths as a function of time. [Figure 18] FIG. 2 is a process diagram of the method according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0105] The inventive concepts are more fully described below with reference to the accompanying drawings, in which presently preferred versions of the inventive concepts are illustrated. However, the inventive concepts may be embodied in many different forms and should not be construed as being limited to the versions set forth herein. Rather, these versions are provided for thoroughness and completeness, and to fully convey the scope of the inventive concepts to those skilled in the art.

[0106] 1 shows a schematic diagram of an apparatus 100 for compiling information about objects and / or for classifying the objects into at least a first and a second class. An object 102 is provided through a first object passage zone 104.

[0107] In the illustrated apparatus 100 of FIG. 1, the object 102 is conveyed through the first object passing zone 104 by a conveyor 108. However, the object 102 may be provided through the first object passing zone 104 by any suitable means, for example by sliding or free falling. For this purpose, the apparatus 100 may be provided with a chute. The conveyor of FIG. 1 is therefore optional. More specifically, this entails that the object is illuminated in the illuminated area 118 by at least one illumination beam for at least a first period of time when the object is transported through the object passing zone by the conveyor 108 at a speed between 0.4 m / s and 20 m / s, or when it is slid through the object passing zone by a chute, or when it is free falling through the object passing zone.

[0108] The illustrated device 100 in Fig. 1 further comprises an optional housing 110 arranged to the side of, and preferably above, the first object passing zone 104. In other words, the housing 110 is arranged above the conveyor 108. Reference is now also made to Fig. 2, which discloses in a schematic manner a selection of components preferably arranged within the optional housing 110.

[0109] Inside the housing 110, an illumination arrangement 114, also referred to as illumination arrangement 114, adapted to emit at least one illumination beam with optical radiation in a first wavelength range towards the scanning element 136, which scanning element is configured to redirect the at least one illumination beam 116 towards the first object passing zone 104. If an object is present in the first object passing zone, a surface portion of this object will be illuminated by the at least one illumination beam. In the context of the present invention, this surface portion illuminated by the at least one illumination beam is referred to as illuminated area 118.

[0110] According to one exemplary embodiment, at least some of the object pieces in the object stream are expected to fluoresce (i.e., when illuminated in the first zone with at least one illumination beam, emit light radiation related to a fluorescent event), which is of interest for detection. In order to facilitate detection of light radiation related to a fluorescent event with radiation in one or more predetermined wavelength bands, it is preferred that at least one illumination beam has no radiation or at least no significant radiation in the one or more predetermined wavelength bands. Although the wavelength range of the light radiation related to the one or more fluorescent events may be wider than the one or more predetermined wavelength bands, the one or more predetermined wavelength bands at least allow to detect a sufficient portion of the light radiation related to the one or more fluorescent events to determine information of interest, e.g. that a fluorescent event has occurred. If the at least one illumination beam is substantially free of light radiation in the one or more wavelength bands, it is a risk that in at least some applications the fluorescent radiation is not distinguishable from the reflected or scattered radiation.

[0111] Provided within the housing 110 is a spectroscopy system 120 adapted to receive and analyze optical radiation 122 reflected, scattered and / or emitted by the objects 102 within the first detection area 104 .

[0112] The illustrated apparatus 100 of Fig. 1 further includes a discharge arrangement 112 disposed downstream of the first object passing zone 104. The discharge arrangement 112 is adapted to discharge and sort the objects 102 to at least two different destinations, although the discharge arrangement 112 of Fig. 1 is optional.

[0113] The illustrated apparatus 100 of Figure 1 further includes a control cabinet 111 disposed above the conveyor 108. The control cabinet 111 contains equipment used to control the apparatus 100. The equipment typically includes a processing unit 113 or control unit for controlling the conveyor 108, the discharge arrangement 112, and the equipment in the housing 110. The processing unit 113 is typically used to determine a property or properties of the object 102 based on measurements performed by the equipment in the housing 110.

[0114] Referring now specifically to Figure 2, there is shown a conceptual diagram of the components inside the housing 110 of Figure 1. Figure 2 also shows a portion of the conveyor 108, including the first object pass-through zone 104.

[0115] In Fig. 2, one of the small arrows in the illuminated area 118 indicates the scanning direction. As can be seen in Fig. 2, the illumination beam intersects the object passing zone at a non-orthogonal angle, i.e. in this example, the illumination beam is non-orthogonal to the conveyor belt in at least one geometrical plane. According to an alternative embodiment, the illumination beam intersects the object passing zone orthogonally, i.e. in this example, the illumination beam is orthogonal to the conveyor belt in at least two geometrical planes.

[0116] The objects 102 are provided through the first object pass zone by a conveyor 108. The objects 102 are typically transported continuously through the first object pass zone 104.

[0117] Further, in conjunction with the illustrated illumination arrangement 114, a first optical arrangement 134 is provided. The first optical arrangement 134 is adapted to direct and optionally converge the at least one illumination beam 116 towards the scanning element 136. The steering element 136 is adapted to redirect the at least one illumination beam 116 along the illumination direction towards the first object passing zone 104 and, if present, towards the illuminated area 118 of the passing object piece. The first optical arrangement 134 is configured to focus the at least one illumination beam in or near the first object passing zone 104, as shown in FIG. 2. The illustrated scanning element 136 in FIG. 2 is in the form of a rotating polygon mirror. Rotating the polygon mirror thus results in redirection and shifting of the illumination direction of the at least one illumination beam 116 in the first object passing zone 104. Thus, the at least one illumination beam 116 will be repeatedly redirected across the first object passage zone 104 for each rotation of the polygon mirror, the number of repetitions being equal to the number of reflective surfaces of the polygon mirror, i.e. 10 for the polygon mirror shown in FIG.

[0118] Other types of scanning elements may be used to advantage, for example a scanning element having only one reflective surface hinged about a pivot axis.

[0119] As mentioned above, the spectroscopic system 120 is adapted to receive and analyze optical radiation 122 reflected, scattered and / or emitted by the object 102 in the first object passing zone 104. Before entering the spectroscopic system 120, the radiation 122 reflected, scattered and / or emitted by the object 102 in the first object passing zone 104 impinges on a scanning element 136, i.e. a polygon mirror, from which the optical radiation 122 is received by an optical element 121 of the spectroscopic system 120. Optionally, the optical path from the polygon mirror 136 to the spectroscopic system 120 comprises a further optical element, for example a fixed folding mirror, which redirects the radiation reflected by the polygon mirror towards an optional housing 121 of the spectroscopic system. The fixed folding mirror may be located in the vicinity of where the at least one illumination beam 116 exits the first optical arrangement 134.

[0120] The spectrometer system 120 may be manufactured by Tomra and may be capable of handling the required number of repetitions. Each spectrometer of the spectrometer system may be configured to analyze optical radiation in the wavelength interval 400-1000 nm, or optical radiation in the wavelength interval 500-1000 nm, or optical radiation in the wavelength interval 1000-1900 nm. Additionally or alternatively, a spectrometer in a spectrometer system may be configured to analyze optical radiation having a wavelength greater than 900 nm. A spectrometer may be configured to analyze optical radiation in the wavelength interval 1900-2500 nm, for example, or a spectrometer may be configured to analyze optical radiation in the wavelength interval 2700-5300 nm. A spectrometer may also be configured to analyze optical radiation in the wavelength interval 900-1700 nm. Additionally or alternatively, a spectrometer of a spectrometer system may be configured to analyze optical radiation in the wavelength interval 700-1400 nm. A spectrometer may analyze visible light. A spectrometer may analyze NIR light. A spectrometer may analyze IR light. Depending on the expected characteristics of the object 102, different types of spectrometers may be used.

[0121] The spectrometer system may comprise one, two or more sensors, for example a first sensor 131 and a second sensor 132. Preferably, each of the one, two or more sensors is an array or matrix sensor comprising a plurality of pixels. Each sensor is also preferably associated with a corresponding diffractive element 128, 129, such as a grating. The sensor-diffractive element pairs are arranged at different locations and are arranged to receive respective corresponding portions of the optical radiation 122, with the different portions of the optical radiation 122 being directed towards the first diffractive element 128 and the second diffractive element 129, respectively. The optical radiation 122 may be split into two different portions, for example by a beam splitting element 123.

[0122] More than one spectrometer may be used in the device 100. For example, the spectroscopic system 120 may include a first sensor 131 adapted to analyze light in a first wavelength interval and a second sensor 120 adapted to analyze light in a second wavelength interval. As an example, the first spectrometer 120 may analyze light in the wavelength interval 450-800 nm and the second spectrometer 120 may analyze optical radiation in the wavelength interval 1500-1900 nm. For example, one spectrometer for visible light may be used in combination with one NIR spectrometer.

[0123] Similarly, two, three, or more spectrometers 120 may be included in the spectroscopic system 120. Thus, two or three spectrometers may be used. For example, one spectrometer for visible light may be used in combination with two NIR spectrometers.

[0124] The spectroscopy system 120 may be a scanning spectroscopy system 120. One example of a suitable scanning spectrometer is manufactured by Tomra.

[0125] Various characteristics of the object 102 in the first object pass zone 104 may be determined based on measurements performed by the spectroscopic system 120 .

[0126] As mentioned above, the illustrated apparatus 100 of Figures 1, 2 and 3 includes a processing unit 113, which in the illustrated apparatus 100 is located within a control cabinet 111. The processing unit 113 is coupled to a spectroscopy system 120, the coupling between which is shown diagrammatically in Figure 2 by a dashed line. The processing unit 113 may be coupled to the spectroscopy system 120 and the camera-based sensor arrangement 128 by any suitable connection, including wired and wireless connections. Any connection capable of transmitting data in any format, digital or analog, may be advantageously used.

[0127] Figures 5a to 5c show views from above of a piece of material on a conveyor belt (not shown). Similar views can be seen by looking at the stream perpendicular or transverse to the transport direction of the stream of material when the material is in free fall, for example at up to + / - 60°, or up to + / - 45°, or up to + / - 30° from the perpendicular direction.

[0128] FIG. 5a shows the positions of the plurality of inspection zones at a first, second and third time point, respectively, where the scanning element is arranged at a first, second and third position, respectively, and at least one illumination beam is directed towards the first object passing zone in a first, second and third illumination direction, respectively. At the first time point, the scanning element is arranged at a first position, and at least one illumination beam is directed along a first illumination direction to illuminate the object in a first illuminated area 118a, marked by a circle in FIG. 5a. The object passing zone comprises a plurality of inspection zones numbered 1 to 8, which are arranged sequentially in a first direction 140. More specifically, a second inspection zone 2 of the plurality of inspection zones is arranged after the first inspection zone with respect to the first direction, and a third inspection zone 3 of the plurality of inspection zones is arranged after the second inspection zone with respect to the first direction. At this first time point, the plurality of inspection zones 1 to 8 are arranged at a first position relative to the object. The first optical arrangement 134, the scanning element and the optical element 125 are preferably arranged such that the illuminated area substantially coincides with the first inspection zone 1 during a first time period.

[0129] At a second time, the scanning element is arranged at a second position relative to the object, and the at least one illumination beam is directed along a second illumination direction to illuminate the object in a second illuminated area 118b, marked by a circle in Fig. 5b. At this second time, the plurality of inspection zones 1-8 are arranged at a second position relative to the object. More specifically, when rotating to the second position, the scanning element shifts the plurality of inspection zones 1-8 and the illumination direction in a first direction relative to the object, whereby the second inspection zone 2 substantially coincides with the first inspection zone before the shift during a second time period after the first time period. As mentioned above, the spectroscopic system 120 comprises a sensor arrangement comprising one or more sensors 131, 132, which is adapted to receive and analyze optical radiation 122 reflected, scattered and / or emitted by an object in at least one of the plurality of inspection zones. More specifically, the sensor arrangement is adapted to receive at least optical radiation 122 emitted by an object in the second inspection zone during a second period of time, the optical radiation relating to phosphorescence events resulting from optical excitation events in the first zone during a first period of time.

[0130] During a third time period, the scanning element is arranged in a third position relative to the object, and the at least one illumination beam is directed along a third illumination direction to illuminate an area 118c outside the object, marked in FIG. 5c by a circle. During this third time period, the plurality of inspection zones 1-8 are arranged in a third position relative to the object. More specifically, when rotating to the third position, the scanning element shifts the plurality of inspection zones 1-8 and the illumination direction in the first direction relative to the object, whereby the third inspection zone 3 substantially coincides with the second inspection zone before the shift during a third time period after the second time period. The sensor arrangement of the spectroscopic system is adapted to receive at least optical radiation 122 emitted by the object in the third inspection zone during the third time period, the optical radiation being related to phosphorescence events resulting from photoexcitation events in the first inspection zone during the first time period.

[0131] During the second and third time periods, and optionally also during the first time period, the optical element is further configured to redirect the received radiation 122 to at least one of the one or more sensors.

[0132] It should be noted that the device 100 is illustrated here with the first direction 140 transverse to the conveyor belt 108. In other words, the scanning direction is orthogonal to the conveyor belt and thus to the movement of the object 102 being transported on the conveyor belt 108. In alternative embodiments, the angular difference between the conveying direction 141 and the first direction 140 may have any value, for example between 0° and less than 360°. Alternatively, the angular difference deviates from 90° by at most + / -70°, or at most + / -50°, or at most + / -30°, or the angular difference deviates from -90° by at most + / -70°, or at most + / -50°, or at most + / -30°. In Figs. 5a to 5c, the angular difference is 90°.

[0133] According to one exemplary embodiment, the number of inspection zones is at least n, and each reflective surface of the scanning element preferably shifts the inspection zones n times before the illumination direction is redirected to the first illumination direction, n being a positive integer. After the illumination direction is redirected preferably to the first illumination direction, the n shifts are preferably repeated.

[0134] As described above, the optical radiation received by the spectrometer system is directed to one or more sensors. The sensor arrangement further comprises a processing circuit configured to collect sensor data based on a sensor signal from the sensor arrangement. The processing circuit may be located anywhere, for example in the spectrometer housing 121 and / or in the processing unit 113, for example partially in the spectrometer housing and partially in the processing unit. Additionally or alternatively, the processing circuit may be located completely or partially in a cloud-based solution.

[0135] More specifically, the processing circuitry is configured to perform a second zone collection function configured to collect second zone data based on at least one sensor signal from one or more sensors, the at least one sensor signal related to optical radiation emitted by an object within the second inspection zone.

[0136] According to one example, during and / or after the second time period, the first sensor outputs at least one signal corresponding to the optical radiation received by that sensor from the second inspection zone during the second time period, and optionally more sensors, such as a second sensor, do the same, and this at least one signal from the one or more sensors may be referred to as at least one second zone sensor signal.

[0137] Also, during and / or after the third time period, the first sensor outputs at least one signal corresponding to the optical radiation received by that sensor from the third inspection zone during the third time period, and optionally more sensors do the same, such as the second sensor, This at least one signal from the one or more sensors may be referred to as at least one third zone sensor signal.

[0138] Generally, during and / or after the nth epoch, for example a first sensor will output at least one signal corresponding to the optical radiation received by that sensor from the nth inspection zone during the nth epoch, and optionally more sensors, such as a second sensor, will do the same. This at least one signal from one or more sensors may be referred to as at least one nth zone sensor signal.

[0139] The processing circuit is configured to perform a second zone collection function configured to collect second zone data based on at least one second zone sensor signal or based on at least one sensor signal from one or more sensors, the at least one sensor signal being related to optical radiation emitted by objects in the second inspection zone. The second zone data can be a representation of all or part of the information present in the at least one second zone sensor signal. According to one example, the at least one second zone sensor signal is a continuous analog signal from a plurality of pixels representing a plurality of wavelength bands, while the second zone data is sampled values ​​of the analog signals from all or part of the wavelength bands.

[0140] The processing circuitry is also configured to perform a third zone collection function configured to collect third zone data based on at least one third zone sensor signal or based on at least one sensor signal from one or more sensors, the at least one sensor signal related to optical radiation emitted by an object within the third inspection zone.

[0141] In general, the processing circuitry may be configured to perform an nth zone collection function configured to collect nth zone data based on at least one nth zone sensor signal or based on at least one sensor signal from one or more sensors, the at least one sensor signal relating to optical radiation emitted by an object in the nth inspection zone. The nth zone data may be a representation of all or part of the information present in the at least one nth zone sensor signal. According to one example, the at least one nth zone sensor signal is a plurality of continuous analog signals from a plurality of pixels each associated with a respective one wavelength band, while the nth zone data is sampled values ​​of the analog signals from all or a portion of the pixels. Additionally or alternatively, the at least one nth zone sensor signal comprises a continuous analog signal from a pixel, while the nth zone data is sampled values ​​of a portion, all, or a discontinuous portion of the analog signal. However, it is optional for the at least one nth zone sensor signal to comprise one or more analog signals. The at least one nth zone sensor signal may comprise any type of data and / or signal, either ongoing or raw.

[0142] The processing circuitry is configured to perform a classification function to classify the object based on at least the second through nth zone data, where n is 3. In other words, the processing circuitry is configured to perform a classification function to classify the object based on at least the second zone data and the third zone data.

[0143] The processing circuitry may be configured, for example, to classify the object based on the first to nth zone data or the second to nth zone data, where n is the number of shifts performed by the scanning element in the first direction before the illumination direction is redirected to the first illumination direction.

[0144] In general, the processing circuitry may be configured to classify the object based on a predetermined selection of two, three, four or more of the first to nth zone data, where n is the number of shifts performed by the scanning element in the first direction before the illumination direction is redirected to the first illumination direction.

[0145] The processing circuitry is configured to perform an output function configured to output a classification signal that assigns one of at least a first class and a second class to the object based on an output of the classification function.

[0146] In FIG. 6, intensity data from a material that emits both fluorescence and phosphorescence is shown, where a first set of sensor pixels detects fluorescence and a second set of sensor pixels detects phosphorescence, where the second set of sensor pixels is different from the first set of sensor pixels, and where the first and second sets of sensor pixels belong to the same sensor or different sensors in the spectroscopic system. In FIG. 6, data from eight collection functions (first collection function to eighth collection function) are shown sequentially, where the nth collection function comprises intensity data (y-axis) from the nth time period. During the first time period, labeled 1 on the x-axis, increasing and decreasing light emission from a fluorescent event detected by the first set of pixels and collected by the first zone collection function is shown. During the second time period to the eighth time period, labeled 8 on the x-axis, increasing and decreasing light emission from a phosphorescent event detected by the second set of pixels and collected by the second to eighth zone collection functions is shown. As can be seen in FIG. 6, the decay of the phosphorescent event is significantly slower compared to the fluorescent event.

[0147] Different characteristics of the fluorescent and / or phosphorus events can be used to classify the objects. Such characteristics can be one, two, three or more of the following: presence / absence, intensity above a predefined threshold, rise time, decay time, strongest wavelength band. These characteristics can be determined for one or both of the fluorescent and / or phosphorus events and can be compared to preset values ​​and / or look-up tables. Additionally or alternatively, one characteristic of one of the events can be compared to one characteristic of the other of the events. For example, the maximum intensity of the fluorescent event can be compared to the decay time of the phosphorus event. Additionally or alternatively, one characteristic of one of the events can be compared to another characteristic of the same event. For example, the maximum intensity of the phosphorus event can be compared to the decay time of the phosphorus event.

[0148] Figures 7 to 11 show intensity data of fluorescent and / or phosphorescent events from different types of objects. The graphs clearly show that the intensity data can be used to distinguish different types of materials from each other based on, for example, peak intensity, rise and decay times, and peak width, and / or occurrence of fluorescent and / or phosphorescent events. In all measurements, the object was illuminated by a 365 nm UV LED emitter OSRAM LZ4-V4UV0R-0000 and the emitted radiation was recorded.

[0149] Figures 7a, 8a, 9a, and 10a show the intensity data as a function of wavelength, where the illuminated objects are a white piece of paper, a yellow glowing bottle, a blue marker, and a red marker, respectively. Each line represents one triggered experiment. Figures 7b, 8b, 9b, and 10b show the corresponding illumination timelines, with the vertical stripes labeled corresponding to different timings of the intensity data in Figures 7a, 8a, 9a, and 10a.

[0150] For example, in Fig. 7a, where the illuminated object is a white piece of paper, intensity lines are shown for different experiments at five different times, labeled A-E on the timeline in Fig. 7b. Times A and E are taken before and after illumination, i.e. under ambient light conditions. Times B, C, D are the beginning, middle and end of illumination. As can be seen, there is a spread in the recorded intensity during the illumination of the object. However, there is a clear cut-off, i.e. no afterglow is recorded after the end of illumination, i.e. in this case there is only fluorescence and no phosphorescence. The intensity lines also have a characteristic shape.

[0151] Figures 8a,b and 9a,b show a similar example where a yellow bottle and a blue marker are illuminated, respectively. As with Figures 7a,b, the times labeled A and E in each of Figures 8a,b and 9a,b are before and after illumination, respectively. The times labeled B, C, and D are the beginning, middle, and end of illumination. The recorded intensities are different for each object (different peak heights / shapes), but in each case, only fluorescence is detected. There is now afterglow, i.e., no phosphorescence.

[0152] In Figure 10a,b the illuminated object is a red marker. The times labelled A-E are taken at times relating to the same illumination as the corresponding labelling in Figures 7 to 9. As in the previous example, the intensity is low at time A, before illumination. It rises at times B and C, i.e. the beginning and middle of illumination, and reaches its maximum value at time D, the end of illumination. At time E, after illumination, a clear intensity peak is still recorded. There is an afterglow, i.e. a phosphorescence event is recorded. At time F, which occurs approximately 1.25 ms after the end of illumination, the afterglow is still detectable.

[0153] Intensity data from experiments on different objects from Figures 7 to 10 are presented simultaneously in Figure 11. The clusters of peaks labeled M1, M2, M3, and M4 correspond to the white paper, yellow bottle, blue marker, and red marker from Figures 7 to 10, respectively. Figure 11 clearly shows that materials can be classified based on the height and shape of the intensity peaks obtained.

[0154] Figures 12 to 15 are plots of the average intensities measured during different experiments in which the illuminated objects were white paper, a yellow glowing bottle, a blue marker, and a red marker, respectively. Thus, each line in Figure 12 shows the average intensities measured at times labeled A to E in Figures 7a and 7b. Figures 13 to 15 similarly show the average intensities at times labeled A to E in Figures 8a,b to 10a,b, respectively.

[0155] In Figures 12-15, the line labeled "205" (as in "Paper 205", "Yellow 205", etc.) corresponds to time A, the line labeled "220" corresponds to time B, the line labeled "230" corresponds to time C, the line labeled "240" corresponds to time D, and the line labeled "250" corresponds to time E. In Figures 12-14, the average intensity is essentially null at times A and E before illumination begins and after illumination ends, but there are characteristic peaks at times B, C, and D. In Figure 15, for the red marker, there is still a characteristic peak at time E after illumination has ended, indicating the presence of phosphorescence.

[0156] The absence or presence of phosphorescence is clearly shown in Figures 16 and 17, which show the maximum intensity recorded across all wavelengths as a function of time for white paper and red marker, respectively. For the white paper in Figure 16, the maximum intensity drops to 0 as soon as the illumination is terminated. In contrast, for the red marker in Figure 17, there is an afterglow, i.e. the maximum intensity drops much more slowly, indicating the presence of phosphorescence.

[0157] Optionally, the apparatus may be configured such that optical radiation 122 from a plurality of inspection zones, e.g. at least two, or at least three, or at least four, or at least eight, or at least twenty inspections, is received simultaneously by the optical element during a predetermined time interval, and the optical element redirects the simultaneously received optical radiation towards the sensor arrangement, where the simultaneously received optical radiation from the plurality of inspection zones (referred to as simultaneous optical radiation) is analysed by the sensor arrangement, the analysed simultaneous optical radiation comprising a portion of the radiation from each one of the plurality of inspection zones. According to one example, the scanning element and the optical element are configured to receive and redirect simultaneously optical radiation from at least the second and third inspection zones, e.g. also from the first inspection zone, during at least the second and third time intervals.

[0158] To illustrate, for example, when there are four shifts and at least one illumination beam is directed towards the first object passage zone in a fifth illumination direction, the sensor may receive light radiation simultaneously from the first, second, third, fourth and fifth inspection zones. If the light radiation received from the first inspection zone indicates the color and / or fluorescence of the object in the currently illuminated portion, the light radiation received simultaneously from the second inspection zone indicates the phosphorescence of the object in the portion illuminated one period ago, the light radiation received simultaneously from the third inspection zone indicates the phosphorescence of the object in the portion illuminated two periods ago, the light radiation received simultaneously from the fourth inspection zone indicates the phosphorescence of the object in the portion illuminated three periods ago and the light radiation received simultaneously from the fifth inspection zone indicates the phosphorescence of the object in the portion illuminated four periods ago. By sorting together data belonging to the same portion of the object over time, information can be gathered about the light radiation reflected, scattered or emitted from that portion of the object. Similarly, by culling together data belonging to different object pieces over time, information can be gathered about the optical radiation reflected, scattered or emitted from those different pieces. Although this example describes the use of five simultaneous inspection zones, the same can be done by using any number of inspection zones.

[0159] Simultaneous measurements from multiple inspection zones may increase the accuracy of the measurements but are optional. Information about the optical radiation reflected, scattered or emitted from one object piece or from different object pieces may be gathered by using only one inspection zone in each time interval.

[0160] According to one exemplary embodiment, the processing circuitry of the illustrated device 100 is configured to classify the object based on a first set of characteristics for the object 102 in the first detection zone 104. The first set of characteristics can be any set of data, including any type of data. The first set of characteristics can include any number of characteristics. The first set of characteristics is determined based on an output signal S1 of at least one sensor of the spectroscopy system 120. The signal S1 can include any type of data, ongoing or raw. Thus, the processing circuitry is configured to receive and analyze data based on the output signal S1 of the spectroscopy system 120, and to determine the first set of characteristics based on the signal S1.

[0161] The first set of characteristics may indicate at least one of the spectral response of the object 102, the material type of the object, the color of the object, the fluorescence of the object, the maturity of the object, the dry matter content of the object, the water content of the object, the fat content of the object, the oil content of the object, the heat value of the object, the presence of bones or fish bones in the object, the presence of pests in the object, the mineral type of the object, the ore type of the object, the defect level of the object, detection of hazardous biological material in the object, the presence of the object, the absence of the object, detection of multi-layer materials in the object, detection of fluorescent markers in the object, the quality grade of the object, the physical structure of the surface of the object, and the molecular structure of the object.

[0162] The processing circuitry may also include processing capabilities that may be used to process actual raw data from one or more spectrometers of the spectroscopy system 120. This means that the spectroscopy system 120 may be able to determine the characteristics or characteristics to be included in the first characteristic set. In other words, the processing unit 113 may be configured to simply include already processed data from the spectroscopy system 120 in the first characteristic set.

[0163] Different properties are typically included in the first property set for different applications of the device 100. In other words, the first property set typically exhibits different characteristics for different applications of the device 100.

[0164] In waste recycling applications, the first set of properties typically refers to the polymeric material, the sleeve material, and the cap material.

[0165] In applications where fruits or vegetables are being sorted, the first set of properties typically indicates foreign objects such as polymers, stones, and shells.

[0166] In applications where wood is being sorted, the first set of characteristics typically indicates the type of wood and the presence of foreign materials.

[0167] The apparatus may optionally further comprise a camera-based sensor arrangement 128, such as a laser triangulation system 124, for determining one or more further parameters of the object or for measuring objects within the first object passing zone 104 or the second object passing zone 106, the second object passing zone being positioned, fully or partially, upstream or downstream of the first object passing zone.

[0168] According to one example, a camera-based detector system may be used to determine the height or width of a passing object to facilitate ejection of the object.

[0169] The discharge arrangement 112 of the depicted device 100 is coupled to a processing unit 113. The discharge arrangement 112 is adapted to discharge and thus sort the objects 102 into a first and second class or into multiple classes or pieces. For example, the objects 102 may be sorted into one scrap piece and one used piece. In case of fruits and vegetables, the objects 102, i.e. fruits and vegetables, may be sorted into multiple classes based on color, i.e. color corresponds to ripeness level, blemishes or the presence of foreign material.

[0170] The ejection and sorting performed by the ejection arrangement 112 may be initiated in response to receiving a signal from the processing unit 113. The signal from the processing unit 113 is typically based on the determined first set of properties and / or the determined second set of properties. Thus, objects may be sorted based on the analysis performed by the spectroscopic system 120 and / or the camera-based system.

[0171] The signal so received may be a simple on / off signal, or may be a complex signal including, for example, the specific coordinates of the object 102 as it approaches the ejection arrangement 112. In the latter case, the ejection arrangement 112 may thus strike or grab a particular object 102 that meets certain criteria, and may do so at a particular location, so that the object 102 is ejected and thus sorted.

[0172] To perform the actual discharge and sorting, the discharge arrangement 112 may include compressed air jets, pressurized water jets, mechanical fingers, bars of compressed air jets, bars of pressurized water jets, bars of mechanical fingers, robotic arms, and mechanical diverters. The entities and principles used to perform the discharge and sorting are therefore known per se in the art.

[0173] According to Fig. 18, when one VIS spectrometer and one NIR spectrometer are used and the at least one illumination beam comprises one focused UV illumination beam and one focused NIR illumination beam, the following processing of the collected zone data can be performed: the NIR spectrometer detects radiation only from illuminated inspection zone 1, and the VIS spectrometer detects radiation from inspection zones 1 to n.

[0174] According to one exemplary embodiment, to associate each inspection zone data with the same portion of the object, the following procedure may be used. Calculate the NIR pixels in zone 1 P_a=pix(z_1) For each zone (i:2..8) Calculate the NIR pixel in zone i: P_b=pix(z_i) Add the VIS spectrum of zone i to all pixels between P_a and P_b For each NIR pixel (j:P_a..P_b+1) Add VIS pixel j, zone i P_a=P_b where z is the cc distance [mm] between the two inspection zones.

[0175] In detection zones 2-8, phosphorescence spectra may occur. Among the zones, the zone with the maximum phosphorescence intensity is searched for (maxP(D2,..,D8). The phosphorescence spectrum of the maximum zone is considered as the phosphorescence spectrum of the measurement. To improve the SNR of the phosphorescence signal, adjacent zones may be used v_p. In extreme cases, the data are integrated in the TDI method (time delay integration).

[0176] Additionally or alternatively, two series of data may be provided, one from a VIS spectrometer and one from a NIR spectrometer. The following processing may be performed, for example, when processing the data and classifying the objects: Each data series is pre-processed, for example, by performing a dark subtraction, a white calibration, and / or a temperature calibration. One or both of the data series may also be compensated for ambient light by ambient light subtraction. One or both of the data series may then be subjected to one or more steps of spectral processing. Spectral processing may involve onset and decay analysis to determine information related to the onset and decay of different spectra, and / or time delay integration to integrate the spectra, and / or a cross comparison of several spectra to determine the best spectrum. After the optional one or more steps of spectral processing, the model continues with a classification model step, preferably where one or more NIR data sets representing one or more NIR spectra and one or more VIS data sets representing one or more VIS spectra are preferably provided. One or more NIR data sets may be processed to perform material classification, i.e., to determine what material or materials the substance is made of. One or more VIS data sets may be processed to perform fluorescence / phosphorescence classification, where the VIS data is matched against one or more criteria to determine or classify the material / marker based on features in the fluorescence-phosphorescence spectrum of the object. Optionally, one or more VIS data may be processed to determine or classify the color of the object. The results of the classification model step are then provided to a resulting synthesis, where the classification results are processed to provide a resulting classification. After the resulting synthesis, the output, optionally together with initial or processed data from the NIR and / or VIS spectrometers, may be provided for object processing, such as further image processing, cleaning or evacuation.

[0177] Thus, it should be understood that the inventive concept is not limited to the specific components of the described devices, as such devices may vary. It should also be understood that the terminology used herein is for the purpose of describing the particular variations only, and is not intended to be limiting. It should be noted that, as used in this specification and the appended claims, the articles "a," "an," "the," and "said" are intended to mean that there is one or more of the element, unless the context clearly dictates otherwise. Thus, for example, reference to "a unit" or "the unit" may include several devices, etc. Also, the terms "comprising," "including," "containing," and similar expressions do not exclude other elements. Furthermore, items described as part of a whole may also be used alone by themselves.

[0178] Itemized List of Embodiments Item 1. An apparatus (100) for classifying an object (102) into one of at least a first class and a second class, comprising: an illumination arrangement (114); A scanning element (136); a spectroscopic system (120), the illumination arrangement is adapted to emit at least one illumination beam (116) comprising optical radiation, the illumination beam being configured to cause a photoexcitation event in the photoresponsive portion of the object upon illumination of the photoresponsive portion of the object by the at least one illumination beam; the illumination arrangement further comprises a first optical arrangement (134) adapted to direct and optionally focus the at least one illumination beam towards the scanning element for at least a first period of time; the scanning element is configured to redirect the at least one illumination beam along an illumination direction towards the object passing zone (104), whereby the object is illuminated by the at least one illumination beam in the illuminated area (118) during at least a first period of time as it is transported or falls freely on the conveyor belt (108) through the object passing zone, for example at a speed between 0.4 m / s and 20 m / s; The spectroscopic system (120) comprises a sensor arrangement comprising one or more sensors (131, 132), the sensor arrangement being adapted to receive and analyze optical radiation reflected, scattered and / or emitted by an object in at least one of a plurality of inspection zones (1-8) arranged sequentially in a first direction (140); a first inspection zone (1) of the plurality of inspection zones substantially coincides with the illuminated area for a first period of time; a second inspection zone (2) of the plurality of inspection zones is disposed after the first inspection zone (1) with respect to the first direction (140); a third inspection zone (3) of the plurality of inspection zones is disposed after the second inspection zone (2) with respect to the first direction (140); and, the scanning element is further adapted to shift the plurality of inspection zones and the illumination direction in a first direction relative to the object, whereby the second inspection zones substantially coincide with the first inspection zones prior to the shift for a second period of time after the first period of time; the scanning element is further adapted to shift the plurality of inspection zones and the illuminated area in a first direction relative to the object, whereby the third inspection zone substantially coincides with the second inspection zone prior to the shift for a third time period after the second time period; The spectroscopic system further includes an optical element, the optical element being configured to: optical radiation emitted by objects in the second inspection zone during a second time period, the optical radiation being related to phosphorescence events resulting from photoexcitation events in the first inspection zone during the first time period; and optical radiation emitted by an object in the third inspection zone during a third time period, the optical radiation being related to a phosphorescence event resulting from a photoexcitation event in the first inspection zone during the first time period; and and configured to receive configured to redirect the received optical radiation to at least one of the one or more sensors; The sensor arrangement is further a second zone collection function configured to collect second zone data based on at least one sensor signal from one or more sensors, the at least one sensor signal relating to optical radiation emitted by objects in the second inspection zone; and a third zone collection function configured to collect third zone data based on at least one sensor signal from one or more sensors, the at least one sensor signal relating to optical radiation emitted by objects in the third inspection zone; a classification function configured to classify the object based on the second zone data and the third zone data; an output function configured to output a classification signal that assigns one of at least a first class and a second class to the object based on an output of the classification function; 23. An apparatus comprising: a processing circuit configured to perform the steps of: Item 2. The scanning element (136) and the optical element are further configured to receive and redirect optical radiation from at least the second inspection zone (2) and the third inspection zone (3) toward the sensor arrangement simultaneously during at least the second and third time intervals; The device (100) of item 1, wherein the sensor arrangement comprises at least one sensor array, each of the at least one sensor array having a plurality of sensor pixels, and the at least one sensor array is arranged such that optical radiation reflected, scattered and / or emitted by an object (102) in a respective inspection zone is received on a respective corresponding set of sensor pixels of the at least one sensor array, the pixels of the respective corresponding set of sensor pixels being different or only partially overlapping. Item 3. The optical element further includes a scanning element (136), light radiation relating to at least one illumination beam reflected and / or scattered by an object (102) in a first inspection zone (1) during a first time period, and / or during a first time period, light radiation emitted by the object associated with a fluorescence event resulting from a light excitation event in the first examination zone. is configured to receive The processing circuitry further comprises: a first zone collection function configured to collect first zone data based on at least one sensor signal from one or more sensors, the sensor signal relating to optical radiation reflected, scattered, and / or emitted by objects in the first inspection zone; is configured to run the classification functionality is further configured to classify the object based on the first zone data; 3. The device (100) according to any one of items 1 to 2. Item 4. The fluorescent portion of the light-responsive portion of the object (102) emits light radiation upon illumination with at least one illumination beam in the first zone (1), the light radiation being related to a fluorescent event and comprising light radiation within one or more wavelength bands, and each piece of the object of the fluorescent portion of the light-responsive portion of the object emits radiation within at least one of the one or more wavelength bands upon illumination with the at least one illumination beam; at least one illumination beam is substantially free of optical radiation within one or more wavelength bands; Optionally, the at least one illumination beam is comprised of optical radiation within at least one low wavelength range and at least one high wavelength range, and each of the one or more wavelength bands is optionally comprised of optical radiation within a wavelength range different from both the low wavelength range and the high wavelength range. 4. The device (100) according to any one of items 1 to 3. Item 5. The scanning element (136) is a polygon mirror configured to rotate in a first direction about a rotation axis, the polygon mirror having a set of reflective surfaces arranged one after the other around the rotation axis; each reflective surface of the set of reflective surfaces is configured to receive optical radiation from the first inspection zone (1), the second inspection zone (2), and the third inspection zone (3) during at least a respective corresponding one of three successive time periods; 5. The device (100) according to any one of items 1 to 4. Item 6. The sensor arrangement comprises a first sensor (131) and a first diffractive element, and a second sensor (132) and a second diffractive element, and the optical elements are: directing optical radiation within a first wavelength range to only a first grating of the first and second gratings and to only a first sensor of the first and second sensors; Directing optical radiation within a second wavelength range to only the second diffraction grating of the first and second diffraction gratings and to only the second sensor of the first and second sensors. It is structured as follows: The first wavelength range and the second wavelength range may be the same, different, or only partially overlapping; 6. The apparatus (100) according to any one of items 1 to 5. Item 7. The sensor arrangement includes a first sensor (131), and the optical element is directing optical radiation within a first wavelength range to a first sensor for a first time period; Directing optical radiation within a second wavelength range to a second sensor during a second time period different from the first time period. It is structured as follows: the first wavelength range and the second wavelength range are different or only partially overlapping; 6. The device (100) according to any one of the preceding items 1 to 5. Item 8. The device (100) of any one of items 1 to 7, wherein the illumination arrangement (114) comprises at least two illumination arrangements, the optical axes of which are incident on the scanning element (136) from different directions, each of the at least two illumination arrangements adapted to emit optical radiation in different or only partially overlapping wavelength ranges, the optical radiation in the different or only partially overlapping wavelength ranges being emitted simultaneously or sequentially. Item 9. The device (100) according to any one of items 1 to 8, wherein the irradiation arrangement (114) comprises at least one irradiation arrangement adapted to emit optical radiation in different or only partially overlapping wavelength ranges at different times. Item 10. An apparatus (100) according to any one of items 1 to 9, wherein one of the one or more sensors comprises a sensor array, the sensor array having a plurality of sensor pixels arranged such that optical radiation reflected, scattered and / or emitted by an object (102) in the second inspection zone (2) is received on a second set of sensor pixels of the sensor array, and such that optical radiation emitted by an object in the third inspection zone (3) is simultaneously received on a third set of sensor pixels of the sensor array, the pixels of the first and second sets of sensor pixels being different or only partially identical. Item 11. An apparatus (100) as described in Item 10 when dependent on at least Item 2, further comprising: a plurality of sensor pixels arranged such that optical radiation emitted by an object (102) in the first inspection zone (1) is received on a first set of sensor pixels of the sensor array, the pixels of the first set of pixels being different from or only partially overlapping with the first and second sets of sensor pixels. Item 12. The device comprises a further sensor arrangement adapted to receive and analyze optical radiation reflected and / or scattered by objects in the illuminated area, and the processing circuitry optionally further comprises: a fourth collection function configured to collect fourth data based on a fourth sensor signal from a further sensor arrangement, the fourth sensor signal relating to optical radiation reflected and / or scattered by objects in the illuminated area; 12. The apparatus of any one of items 1 to 11, configured to execute the steps: Item 13. A method for classifying objects (102) to be transported in bulk into at least one of a first class and a second class, comprising: Emitting and directing at least one illumination beam comprising optical radiation towards an object passage zone (104); illuminating an illuminated area (118) of an object (102) with at least one illumination beam at least for at least a first time period, wherein the object (102) is transported or free-falls on a conveyor belt (108) at a speed between 0.4 m / s and 20 m / s in an object passing zone, thereby causing photoexcitation events in photoresponsive portions of the object (102); Directing optical radiation via a scanning element (136) towards one or more sensors of the sensor arrangement, the optical radiation being scattered and / or emitted by an object in at least one of a plurality of inspection zones (1-8) arranged sequentially in a first direction (140), a first inspection zone (1) of the plurality of inspection zones (1-8) substantially coinciding with the illuminated area (118) and a second inspection zone (2) of the plurality of inspection zones (1-8) being arranged after the first inspection zone with respect to the first direction (140); shifting the plurality of inspection zones and the illuminated area in a first direction (140) with the scanning element relative to the object (102) such that a second inspection zone at a second time after the first period of time substantially coincides with the first inspection zone at the first time; thereafter, receiving, by the sensor arrangement, optical radiation emitted by the object (102) in the second inspection zone during a second time period, the optical radiation emitted by the object (102) in the second inspection zone relating to a phosphorescence event resulting from the photoexcitation event; collecting first phosphorescence data related to received light emitted by the object (102) within the second inspection zone during a second time period; shifting the plurality of inspection zones and the illuminated area in a first direction (140) relative to the object (102) by the scanning element such that a third inspection zone at a third time point after the second time period substantially coincides with the second inspection zone at the second time point; thereafter, receiving, by the sensor arrangement, optical radiation emitted by the object (102) in the third inspection zone during a third time period, the optical radiation emitted by the object (102) in the third inspection zone relating to a phosphorescence event resulting from the photoexcitation event; collecting second phosphorescence data related to received light emitted by objects (102) within the third inspection zone during a third time period; and classifying, by a processing circuit, the object (102) based on the second zone data and the third zone data; outputting, by the processing circuitry, a classification signal that assigns one of at least a first class and a second class to the object based on the results of the classifying; A method for providing the above. Item 14. Receiving, at one or more sensors of the sensor arrangement during at least a first time period, optical radiation reflected, scattered, and / or emitted by objects (102) in a first inspection zone, wherein the optical radiation reflected and / or scattered by the objects in the first inspection zone is related to the at least one illumination beam, and the optical radiation emitted by the objects in the first inspection zone is related to a fluorescence event resulting from a photoexcitation event; collecting first zone data relating to received optical radiation reflected, scattered, and / or emitted by objects within a first examination area during at least a first time period; Item 14. The method of item 13, further comprising: Item 15. The method of item 14, wherein the first zone data is a representation of at least a first spectrum, and classifying the object comprises determining a wavelength distribution of the first spectrum, and optionally determining at least one characteristic related to a shape of the first spectrum, such as a peak height, a peak width, and / or a peak area of ​​one or more peaks. Item 16. The method of any one of items 13 to 15, further comprising forming phosphorus data based on at least the second zone data and the third zone data, the phosphorus data being a representation of at least a second spectrum, such as a phosphorescence spectrum, and classifying the object comprises determining a wavelength distribution of the second spectrum, and optionally determining at least one characteristic related to a shape of the second spectrum, such as a peak height, a peak width, and / or a peak area of ​​one or more peaks. Item 17. The method of any one of items 13 to 16, wherein classifying the object comprises determining the rise time and / or decay time of a phosphorescence event. Item 18. Classifying objects further involves: At least one characteristic related to a phosphorescence event of the object; and at least one characteristic related to a respective one of the object's color, transmittance, reflectance, and fluorescence; classifying the object based on 18. The method according to any one of items 13 to 17. Item 19. The method of item 18, wherein the step of classifying the object further comprises comparing at least one property related to the phosphorescence of the object, as well as one or more other properties related to a corresponding one of the object's color, transmittance, reflectance, and fluorescence, to data stored in a local database or a centralized database. Item 20. Classification can be further determining whether the object is provided with phosphorus markers by at least one of image processing and spectral processing; and / or Identifying, for example by spectral processing, one or more materials that make up the object; and / or Determining the materials that make up a single piece of material and determining whether the combination of these materials is acceptable or unacceptable 21. The method according to any one of items 13 to 20, comprising: Item 21. The method of any one of items 13 to 20, wherein at least one illumination beam that causes a photoexcitation event comprises light radiation in the ultraviolet and / or visible wavelength range. Item 22. Emitting and directing at least one illumination beam comprises emitting and directing at least one illumination beam comprising optical radiation within one or a combination of ultraviolet, visible, near infrared, and infrared wavelength ranges; and / or receiving optical radiation reflected, scattered, and / or emitted by objects in the first inspection zone comprises receiving optical radiation within one or a combination of ultraviolet, visible, near infrared, and infrared wavelength ranges; 22. The method according to any one of items 13 to 21. Item 23. Sensor placement is a first sensor configured to detect optical radiation within an ultraviolet and / or visible wavelength range; and a second sensor configured to detect optical radiation within the near infrared and / or infrared wavelength range; and 23. The method according to any one of items 13 to 22, comprising:

Claims

1. An apparatus (100) for classifying an object (102) into one of at least a first class and a second class, comprising: an illumination arrangement (114); A scanning element (136); A spectroscopic system (120); a conveyor (108) for transporting said objects (102) or a chute, optionally including a vibratory feeder, for sliding or free-falling of said objects (102), the illumination arrangement is adapted to emit at least one illumination beam (116) comprising optical radiation, the illumination beam configured to cause a photoexcitation event in the photoresponsive portion of the object (102) upon illumination of the photoresponsive portion of the object by the at least one illumination beam; the illumination arrangement further comprises a first optical arrangement (134) adapted to direct and optionally focus the at least one illumination beam towards the scanning element for at least a first time period; the scanning element is configured to redirect the at least one illumination beam along an illumination direction towards an object passing zone (104), whereby the object is illuminated by the at least one illumination beam in an illuminated area (118) during at least a first period of time when it is transported by the conveyor (108) through the object passing zone, for example at a speed between 0.4 m / s and 20 m / s, or when it is slid by the chute or falls freely, The spectroscopic system (120) comprises a sensor arrangement comprising one or more sensors (131, 132), the sensor arrangement being adapted to receive and analyze optical radiation reflected, scattered and / or emitted by the object in at least one of a plurality of inspection zones (1-8) arranged sequentially in a first direction (140), a first inspection zone (1) of the plurality of inspection zones substantially coincides with the illuminated area during the first time period; a second inspection zone (2) of the plurality of inspection zones is arranged after the first inspection zone (1) with respect to the first direction (140); a third inspection zone (3) of the plurality of inspection zones is arranged after the second inspection zone (2) with respect to the first direction (140); and, the scanning element is further adapted to shift the plurality of inspection zones and the illumination direction in the first direction relative to the object, whereby the second inspection zone substantially coincides with the first inspection zone prior to the shift for a second period of time after the first period of time; the scanning element is further adapted to shift the plurality of inspection zones and the illuminated area in the first direction relative to the object, whereby the third inspection zone substantially coincides with the second inspection zone prior to the shift for a third period of time after the second period of time; The spectroscopic system further includes an optical element, the optical element being configured to: light radiation emitted by the object in the second inspection zone during the second time period, the light radiation being related to a phosphorescence event resulting from the photoexcitation event in the first inspection zone during the first time period; and light radiation emitted by the object in the third inspection zone during the third time period, the light radiation being related to a phosphorescence event resulting from the photoexcitation event in the first inspection zone during the first time period; and and configured to receive configured to redirect the received optical radiation to at least one of the one or more sensors; The sensor arrangement further comprises: a second zone collection function configured to collect second zone data based on at least one sensor signal from the one or more sensors, the at least one sensor signal relating to the optical radiation emitted by the object in the second inspection zone; and a third zone collection function configured to collect third zone data based on at least one sensor signal from the one or more sensors, the at least one sensor signal relating to the optical radiation emitted by the object in the third inspection zone; and a classification function configured to classify the object based on the second zone data and the third zone data; an output function configured to output a classification signal that assigns one of the at least first and second classes to the object based on the output of the classification function; 23. An apparatus comprising: a processing circuit configured to perform the steps of:

2. the scanning element (136) and the optical element are further configured to receive and redirect optical radiation from at least the second inspection zone (2) and the third inspection zone (3) towards the sensor arrangement simultaneously during at least the second and third time intervals; 2. The apparatus (100) of claim 1, wherein the sensor arrangement comprises at least one sensor array, each of the at least one sensor array having a plurality of sensor pixels, the at least one sensor array being arranged such that optical radiation reflected, scattered and / or emitted by the object (102) in each inspection zone is received on a respective corresponding set of sensor pixels of the at least one sensor array, the pixels of the respective corresponding sets of sensor pixels being different or only partially overlapping.

3. The optical element further includes, via the scanning element (136), light radiation relating to said at least one illumination beam reflected and / or scattered by said object (102) in said first inspection zone (1) during said first period of time; and / or during the first period of time, light radiation emitted by the object associated with a fluorescent event resulting from the photoexcitation event in the first examination zone. is configured to receive The processing circuitry further comprises: a first zone collection function configured to collect first zone data based on at least one sensor signal from the one or more sensors, the sensor signal relating to the optical radiation reflected, scattered, and / or emitted by the object in the first inspection zone; is configured to run the classification functionality is further configured to classify the object based also on the first zone data. An apparatus (100) according to any one of claims 1 to 2.

4. a fluorescent portion of the light-responsive portion of the object (102) emits light radiation upon illumination with the at least one illumination beam in the first zone (1), the light radiation being associated with a fluorescent event and comprising light radiation within one or more wavelength bands, and each piece of the object of the fluorescent portion of the light-responsive portion of the object emits radiation within at least one of the one or more wavelength bands upon illumination with the at least one illumination beam; the at least one illumination beam is substantially free of optical radiation within the one or more wavelength bands; Optionally, the at least one illumination beam consists of optical radiation within at least one low wavelength range and at least one high wavelength range, each of the one or more wavelength bands optionally consisting of optical radiation within a wavelength range different from both the low wavelength range and the high wavelength range. An apparatus (100) according to any one of claims 1 to 3.

5. the scanning element (136) is a polygon mirror configured to rotate in a first direction about an axis of rotation, the polygon mirror comprising a set of reflective surfaces arranged one after the other about the axis of rotation; each reflective surface of the set of reflective surfaces is configured to receive optical radiation from the first inspection zone (1), the second inspection zone (2) and the third inspection zone (3) during at least a respective corresponding one of three successive time periods; An apparatus (100) according to any one of claims 1 to 4.

6. The sensor arrangement comprises a first sensor (131) and a first diffractive element, and a second sensor (132) and a second diffractive element, the optical elements being: directing optical radiation within a first wavelength range to only the first grating of the first and second gratings and to only the first sensor of the first and second sensors; directing the optical radiation within a second wavelength range to only the second diffraction grating of the first and second diffraction gratings and to only the second sensor of the first and second sensors. It is structured as follows: The first wavelength range and the second wavelength range are the same, different, or only partially overlapping. An apparatus (100) according to any one of claims 1 to 5.

7. The sensor arrangement comprises a first sensor (131), the optical element comprising: directing optical radiation within a first wavelength range to the first sensor for a first time period; Directing the optical radiation within a second wavelength range to the second sensor for a second time period different from the first time period. It is structured as follows: The first wavelength range and the second wavelength range are different or only partially overlapping. An apparatus (100) according to any one of the preceding claims 1 to 5.

8. 8. The apparatus (100) of claim 1, wherein the illumination arrangement (114) comprises at least two illumination arrangements, the optical axes of which are incident on the scanning element (136) from different directions, each of the at least two illumination arrangements adapted to emit optical radiation in different or only partially overlapping wavelength ranges, the optical radiation in the different or only partially overlapping wavelength ranges being emitted simultaneously or sequentially.

9. 9. The apparatus (100) according to any one of claims 1 to 8, wherein the illumination arrangement (114) comprises at least one illumination arrangement adapted to emit optical radiation in different or only partially overlapping wavelength ranges at different times.

10. 10. The apparatus (100) of claim 1, wherein one of the one or more sensors comprises a sensor array having a plurality of sensor pixels arranged such that optical radiation reflected, scattered and / or emitted by the object (102) in the second inspection zone (2) is received on a second set of sensor pixels of the sensor array and such that optical radiation emitted by the object in the third inspection zone (3) is simultaneously received on a third set of sensor pixels of the sensor array, the pixels of the first and second sets of sensor pixels being different or only partially identical.

11. The apparatus (100) of claim 10 when dependent on at least claim 2, further comprising: the plurality of sensor pixels arranged such that optical radiation emitted by the object (102) in the first inspection zone (1) is received on a first set of sensor pixels of the sensor array, the pixels of the first set of pixels being different from or only partially overlapping with the first and second sets of sensor pixels.

12. The apparatus may comprise a further sensor arrangement adapted to receive and analyze optical radiation reflected and / or scattered by the object in the illuminated area, the processing circuitry optionally further comprising: a fourth collection function configured to collect fourth data based on a fourth sensor signal from the further sensor arrangement, the fourth sensor signal relating to the optical radiation reflected and / or scattered by the object in the illuminated area; 12. The apparatus of claim 1 , configured to:

13. 1. A method for classifying mass-transported objects (102) into one of at least a first class and a second class, comprising: Emitting and directing at least one illumination beam comprising optical radiation towards an object passage zone (104); illuminating an illuminated area (118) of the object (102) with the at least one illumination beam at at least a first time and for at least a first period of time, the object (102) being transported by a conveyor (108) or free-falling at a speed between 0.4 m / s and 20 m / s in the object passing zone, thereby causing a photoexcitation event in a photoresponsive portion of the object (102); directing optical radiation via a scanning element (136) towards one or more sensors of a sensor arrangement, the optical radiation being scattered and / or emitted by the object in at least one of a plurality of inspection zones (1-8) arranged sequentially in a first direction (140), a first inspection zone (1) of the plurality of inspection zones (1-8) substantially coinciding with the illuminated area (118) and a second inspection zone (2) of the plurality of inspection zones (1-8) being arranged after the first inspection zone with respect to the first direction (140); shifting the plurality of inspection zones and the illuminated area in the first direction (140) with the scanning element relative to the object (102) such that the second inspection zones at a second time after the first period of time substantially coincide with the first inspection zones at the first time; thereafter, receiving, by the sensor arrangement, optical radiation emitted by the object (102) in the second inspection zone during a second time period, the optical radiation emitted by the object (102) in the second inspection zone being related to a phosphorescence event resulting from the optical excitation event; collecting first phosphorescence data related to the received light emitted by the object (102) within the second inspection zone during the second time period; shifting the plurality of inspection zones and the illuminated area in the first direction (140) with the scanning element relative to the object (102) such that the third inspection zone at a third time after the second period of time substantially coincides with the second inspection zone at the second time; thereafter, receiving, by the sensor arrangement, optical radiation emitted by the object (102) in the third inspection zone during a third time period, the optical radiation emitted by the object (102) in the third inspection zone being related to a phosphorescence event resulting from the optical excitation event; collecting second phosphorescence data related to the received light emitted by the object (102) within the third inspection zone during the third time period; and classifying, by a processing circuit, the object (102) based on the second zone data and the third zone data; outputting, by the processing circuitry, a classification signal that assigns one of the at least first and second classes to the object based on the result of the classifying; A method for providing the above.

14. receiving optical radiation reflected, scattered and / or emitted by the object (102) in the first inspection zone at the one or more sensors of the sensor arrangement during at least the first time period, the optical radiation reflected and / or scattered by the object in the first inspection zone relating to the at least one illumination beam and the optical radiation emitted by the object in the first inspection zone relating to a fluorescence event resulting from the optical excitation event; collecting first zone data related to the received optical radiation reflected, scattered, and / or emitted by the objects within the first examination area during at least the first time period; The method of claim 13 further comprising:

15. 15. The method of claim 14, wherein the first zone data is a representation of at least a first spectrum, and classifying the object comprises determining a wavelength distribution of the first spectrum, and optionally determining at least one characteristic related to the shape of the first spectrum, such as the peak height, peak width, and / or peak area of ​​one or more peaks.

16. 16. The method of claim 13, further comprising forming phosphorus data based on at least the second zone data and the third zone data, the phosphorus data being a representation of at least a second spectrum, such as a phosphorescence spectrum, and classifying the object comprises determining a wavelength distribution of the second spectrum and, optionally, determining at least one characteristic related to the shape of the second spectrum, such as a peak height, a peak width, and / or a peak area of ​​one or more peaks.

17. 17. The method of any one of claims 13 to 16, wherein classifying the object comprises determining a rise time and / or a decay time of the phosphorescent event.

18. Classifying the object further comprises: at least one characteristic related to the phosphorescence event of the object; and at least one characteristic related to a respective one of the color, the transmittance, the reflectance, and the fluorescence of the object; classifying the object based on 18. The method according to any one of claims 13 to 17.

19. 20. The method of claim 18, wherein the step of classifying the object further comprises comparing the at least one property related to the phosphorescence of the object, and one or more other properties related to a corresponding one of the color, the transmittance, the reflectance, and the fluorescence of the object, to data stored in a local or centralized database.

20. The classifying step further comprises: determining whether said object is provided with phosphorus markers by at least one of image processing and spectral processing; and / or Identifying, for example by spectral processing, the material or materials that make up said object; and / or Determining the materials that make up a piece of material and determining whether the combination of materials is acceptable or unacceptable.

21. The method of any one of claims 13 to 20, comprising:

21. 21. The method of any one of claims 13 to 20, wherein the at least one illumination beam causing the photoexcitation event comprises light radiation within the ultraviolet and / or visible wavelength range.

22. emitting and directing the at least one illumination beam comprises emitting and directing at least one illumination beam comprising optical radiation within one or a combination of the ultraviolet, visible, near infrared, and infrared wavelength ranges; and / or receiving optical radiation reflected, scattered, and / or emitted by the object in the first inspection zone comprises receiving optical radiation within one or a combination of the ultraviolet, visible, near infrared, and infrared wavelength ranges.

22. The method according to any one of claims 13 to 21.

23. The sensor arrangement includes: a first sensor configured to detect optical radiation within the ultraviolet and / or visible wavelength range; and a second sensor configured to detect optical radiation within the near infrared and / or infrared wavelength range; and 23. The method of any one of claims 13 to 22, comprising:

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