RU2261475C2 - Optical device for scanning skin pattern - Google Patents

Abstract

FIELD: biometric person identification.

SUBSTANCE: device has light source, sensor optical element with angle of full inner reflection at glass-water limit, optical lens system, photo-receiver. Light source has light sources matrix. Each element of light sources matrix forms a flat light beam. Light source has prism in form of wedge. Prism forms homogenous total light flow. One of wedge surfaces has raster surface. Sensor optical element can have flat, convex, or concave working surface. Optical system has compensation prism in form of wedge. Optical lens system has two positive lens components. Lens components form an afocal dual telecentric optical system. First lens component consists of two flat-convex lenses, second lens component consists of two meniscuses and two convex-concave lenses.

EFFECT: higher quality, lesser dimensions, higher efficiency.

1 cl, 11 dwg, 1 tbl

Description

The present invention relates to the field of biometric identification of personalities, and more particularly to methods and devices for scanning a pattern of skin lines of fingers, palms, feet, etc., as well as to the field of optical scanning systems, more specifically to special structures, optical projection systems using in the general case, a prism with an angle of total internal reflection with flat faces, cylindrical, conical, etc.

Currently, paintless methods of obtaining fingerprints with direct input to an electronic database using computers are being used more and more, and increasingly increasing demands are placed on scanning devices for the quality of the resulting image with smaller dimensions.

The quality of an optical image of an object is determined by its size, resolution, geometric distortion (distortion), different scale across the image field, frequency-contrast characteristics, aperture.

Fingerprints, palms, etc. used mainly in forensics and access systems to important objects. Better prints increase the accuracy of personal identification and the reliability of access systems.

The smaller dimensions of the device allow more widely and mobile use of well-known methods of biometric identification of individuals.

Depending on the specific application of the fingerprinting device, there can be at least 4 types: palm scanners, fingerprint scanners (4 fingers), scanners for rolling one finger, scanners for taking a fingerprint without rolling.

A wide range of applications allows us to talk about the relevance of the unification of technical solutions.

Currently, the highest image quality of fingerprints, palms, etc. receive optical devices having a illuminator, a sensor optical element in the form of a prism with total internal reflection, a lens system and a photodetector in the form of a linear CCD.

In this case, the object is scanned along the prism’s working surface by a line that is optically conjugated with a linear CCD matrix and which moves frontally either in the direction along the plane of the angle of total internal reflection or in the transverse direction to the plane of this angle.

The first is called longitudinal scanning, the second is called transverse scanning.

A device is known (Pat. No. 05189132 JP, classes: G 06 T 7/00, A 61 B 5/117, G 06 T 1/00, publication number 07-098764, publication date 04/11/1995, priority date 06/30/1993) , which uses longitudinal scanning by linear movements of the scanning mirror, the lens system and the linear CCD matrix, connected by a ratio that ensures the constancy of the optical path in the prism and in the air.

There is an additional optical channel for tracking control when scanning prints.

When increasing the size of the working field, it is required to increase the focal length of the lens system and significantly increase the size of the prism in thickness.

The disadvantage of this device is that scanning is performed with a significantly changing thickness of the prism glass and the complexity of the mechanical drive, which should provide the ratio of the movements of the mirror, the lens system and the linear CCD matrix for a constant optical path.

With a changing glass thickness, image distortion and the frequency-contrast characteristics of the optical channel can change, which can be compensated by the complexity of the lens system.

The versatility of the device is limited.

Closest to the proposed device is (US Pat. No. 5548394 US, classes: 356/71, G 06 K 009/20, August 20, 1996, applicants; Giles at al), which uses transverse scanning by rotating the scanning mirror, while the dimensions scan fields are determined by the size of the first optical lens component.

The optical lens system satisfies the following conditions: Scheimpflug (Smith, Warren J. "Modem Optical Engeneering: the design of optical systems / Warren J. Smith.-2 nd ed", pp. 52-53) - the condition for the angular conjugation of the object and image planes, the telecentricity condition of the input and output rays (dual telecentricity), and also satisfies the condition of correcting distortion and image scale in 2 directions along and across the scanning direction with natural anamorphic image.

There is an additional optical channel for tracking control during scanning.

Scanning is performed at a constant thickness of the prism glass.

A condenser-type illuminator creates a directional parallel beam of light.

The disadvantages of this device are the limitation of the size of the scanning field in two directions by the dimensions of the first lens component, the increased dimensions of the device due to the correction of distortion in two directions throughout the field, which requires an increase in the focal lengths of the optical components, a luminaire having large dimensions, creating a directed beam of light and not having enough high efficiency.

The versatility of the device is limited. The technical result of the present invention is:

1) obtaining high-quality handprints, control prints, rolling fingers, etc. with small distortions and high resolution in accordance with modern requirements for the quality of fingerprint information;

2) reducing the dimensions of the device in comparison with analogues;

3) the universality of the device, which allows to widely unify components, with a wide range of devices with various applications and scanning methods.

To achieve a technical result in an optical device for scanning a skin pattern containing a illuminator having a matrix of light sources, an optical system having a sensor optical element with an angle of total internal reflection at the glass-water interface and an optical lens system forming an optical beam defining an optical image of the skin fingerprint, with the property of dual telecentricity and anamorphic image, satisfying the condition of angular conjugation of the planes of the object and braces, photodetector, each element from the matrix of light sources creates a flat beam of light, for example, using a bifocal lens, a prism with double internal reflection is introduced into the light source, forming a total light stream uniform from the matrix of light sources, directed in the specified direction for the lens system, having the form of a wedge, one of the surfaces of the wedge has a raster surface, the touch optical element can have a convex, flat or concave working surface and is intended for scanning tions relative movement as a linear movement or rotation, the illuminator may be associated with the relative movement of both sensor optical element, and a compensating prism lens system and a photodetector; the optical system immediately behind the touch optical element contains a compensating prism in the form of a wedge, the angle of which is a complementary angle at which the output face of the prism is perpendicular to the optical axis of the lens system; the optical lens system consists of two positive lens components forming an afocal dual telecentric optical system, the first lens component consists of two plane-convex lenses, the first lens is convex towards the image space, the second lens is convex towards the object space, the second lens component consists consistently of two menisci and two convex-concave lenses, the first meniscus is convex towards the object space, the second meniscus is facing you uklostyu toward the image space, the first convexo-concave lens is convex toward the image space, the second convex-concave lens is convex toward the object space.

In addition, in an optical device for scanning a skin pattern, each bifocal lens of the matrix of light sources has a spherical surface input for the light beam, directed concavity toward the light source, and an output cylindrical surface, convex towards the object.

In addition, the illuminator also contains an additional prism, which has a face input to the light beam and an internal reflective face, which together with the wedge prism creates a five-fold internal reflection of the light flux.

In another case, the illuminator contains an additional prism in the form of a wedge, having a face input to the light flux, creating together with the wedge prism a four-fold internal reflection of the light flux.

It is also possible that in the illuminator an additional prism has an input cylindrical surface.

In addition, in the illuminator, the raster surface is made in the form of a set of a large number of narrow inclined mirror faces, so that the raster surface has a sawtooth profile in cross section.

Also, in the illuminator, the raster surface of the wedge prism can be made in the form of a directional or non-directional rough surface.

It is assumed that in the illuminator a wedge prism can have two rough surfaces with directional or non-directional roughness.

In addition, the touch optical element is made in the form of a cylinder and is designed to scan the pattern of skin lines by rotating it about its own axis.

For a better layout, the compensating prism is made with an inclined reflective face that creates a single internal reflection for the working light beam.

Also, it contains an additional mirror between two lens components to refract the optical axis.

In addition, the touch optical element is made in the form of a prism with a flat working surface and is intended for scanning by linear movement of the lens unit and the photodetector along the working plane of the prism.

In this case, it contains an additional optical channel containing a lens system, for example, a lens and a photodetector, designed to control scanning, for example, when rolling fingers.

In order to reduce the size, it additionally contains the first and second mirrors between the first and second lens components and a third mirror between the lens system and the photodetector.

For the same purpose, the additional optical channel contains three mirrors and two glued rectangular prisms, and in the case of combining the additional optical channel with the lens system, the first of the mirrors may be translucent.

In addition, the sensor optical element is made in the form of a truncated cone with a concave conical working surface and is intended for scanning by rotation of the compensating prism, the lens assembly and the photodetector relative to the axis of the conical sensor optical element.

In this case, it additionally contains two mirrors: the first after the first lens component and the second after the second lens component.

Figure 1 shows the main view of the optical device in a generalized form.

Figure 2 shows a illuminator having a wedge prism 20, a raster surface 22, forming an output light flux with an inclination angle α3 greater than 90 °, a matrix of light sources 25 with lenses 24.

Figure 3 shows a similar illuminator having an additional prism 21 and mirror surfaces 29, creating a five-fold internal reflection of the light flux, which allows to reduce the length of the illuminator in length.

Figure 4 a) and figure 4 b) shows in two projections a light source LED with a lens having a spherical surface 26 and a cylindrical surface 27, creating a flat light beam with a divergence angle of thickness β1 and a beam angle β2.

Figure 5 shows a illuminator with a wedge prism having a rough surface 23 for illumination of a predominantly sensor optical element in the form of a cylinder.

Figure 6 shows the tracing of light rays modeled by a special program in the illuminator of figure 3 and a sensor optical element in the form of a prism with total internal reflection from a matrix of 84 LEDs arranged in four rows of 21 pieces in each row, while the flat detector is located behind output face of the prism.

7 shows a picture of the illumination in the plane of the detector, traces of 400,000 rays.

On Fig shows a diagram of an optical device with an optical sensor element in the form of a cylinder 30.

Fig. 9 a) shows a graph of the frequency-contrast characteristics of the lens unit for various image points falling on the linear photodetector in tangential (T) and sagittal (S) directions.

Figure 9 b) shows a diagram of the scattering of points in the image plane with the calculated radius of the scattering of the point in microns.

Fig. 9 c) shows a graph of distortion in the image plane for tangential (T) and sagittal (S) rays.

Figure 10 a) and figure 10 b) shows in two projections an optical device for scanning the skin pattern of the palms, fingerprints, etc. with an optical sensor element in the form of a prism 2 with a flat working surface 18.

11 shows an optical device for scanning a skin pattern of fingers on a conical concave working surface without rolling.

The problem is solved in that in the device of FIG. 1, having a illuminator 1, a prism 2, a compensating prism 3, an optical lens system 4, consisting of two groups of lenses 5 and 6, a linear array photodetector 7, scanning is performed by relative movement in the transverse direction prisms 2 relative to the compensating prism 3, the optical lens system 4, the linear array photodetector 7, forming a single node 8.

There are options in which the node 8 is stationary, the prism 2 moves, or the prism 2 is stationary, the node 8 moves.

The relative movement of the prism 2 and the optical node 8 is possible both in the form of translational movement and rotation about the selected axis.

In this device, the dimensions of the scanning working field are determined in the longitudinal direction only by the height of the first group of lenses 5 and, accordingly, by the longitudinal size of the prism, and in the transverse direction, only by the transverse size of the prism and does not depend on the parameters of the optical lens assembly.

The illuminator can be connected to the prism and illuminate the entire working surface of the prism, or it can be connected to the optical unit and, moving with it, illuminate the area of the scan line.

The compensating prism 3 is distinguished as a separate element in cases when scanning is performed by relative rotation and is necessary to compensate for refractive distortions, which create additional difficult to exclude distortions (aberrations) in the image plane.

If the compensating prism is made of the same glass as the prism, then the output face of the compensating prism should be perpendicular to the optical axis of the lens assembly.

If the compensating prism is of a different glass than the prism, then the output face of the compensating prism should be at an angle to the optical axis of the lens assembly.

This angle should correspond to the angle of minimal wavefront distortions for the entire optical system as a whole.

If scanning is performed by linear transverse movement of the scanning line, then the compensating prism 3 is either an integral part of the prism 2, or can be used to optimize the shape and size of the prism 2.

The illuminator 1, figure 2, consists of a prism 20 in the form of a wedge having a raster surface 22, and a matrix light source, each element of which consists of a lens 24 and a light source 25, for example an LED.

The raster mirror surface 22 with internal reflection is formed by a set of a large number of alternating faces in the form of narrow transverse stripes, inclined at an angle that provides a given angle of inclination α3 of the output light beam.

The angle α3 corresponds to the angle α1 incident on the working surface 8 of the prism 2 of the original light beam.

Lens 24, figa, is a bifocal lens and has an input spherical surface 26 and an output cylindrical surface 27, creating a flat light beam with a transverse angle of divergence β1 and a longitudinal angle of opening β2.

The divergence angle β1 should be consistent with the input aperture angle of the lens unit 4.

A lighter having reduced overall dimensions in length is shown in FIG. 3, characterized in that it further has a prism 21 with an input cylindrical surface 28 and three mirror surfaces 29.

The illuminator for a rotating cylindrical prism is shown in figure 5, characterized in that the raster surface in this case is not required, instead of it a scattering surface 23.

A wedge prism with an angle α1 is required for a more complete input of the light flux at an angle α1 into the end face of a rotating prism.

The design features of the illuminator, in particular the use of a raster, are associated with the layout dimensions of the entire device, the requirement is for an angle α3, which must be greater than 90 degrees, while a uniform light flux throughout the field must be formed and the illuminator must have high efficiency.

The illuminator, Fig. 3, has practically no scattered and absorbed light, its theoretical output coefficient of efficiency is about 88% (excluding losses due to reflection on mirror surfaces 29), which is confirmed by the results of three-dimensional modeling of ray tracing shown in Fig. 6, and counting on the uniformity of illumination of the working field, Fig. 7, where the output energy according to the calculation, falling on the entire working field of the detector, is 37.7 watts against the originally set radiation energy of the source of 42 watts.

The high value of the efficiency, directivity of the light flux and the absence of scattered light make it possible to obtain sufficient illumination of the photosensitive photodetector and to exclude spurious background illumination from the scanning object during operation, which ultimately directly affects the formation of a high-quality image of fingerprints.

The lens system of the device was calculated to obtain a high-quality image from a linear CCD matrix, which depends on the total correspondence of its level of illumination, the frequency-contrast characteristics of the lens system, the sensitivity of the CCD matrix, the number of CCD sensitive elements and their sizes.

The calculated frequency-contrast characteristics, figa, of the lens system of the inventive device have a limit of about 300 lines / mm, the maximum spatial working frequency corresponding to 1000 dpi, about 70 lines / mm with a contrast level of at least 20%.

The size of the standard sensitive element of the CCD matrix is 7 × 7 μm, which corresponds to the dot scatter diagram in FIG.

The first group of lenses 5 consists of two plane convex lenses 9 and 10, convex to each other.

The second group of lenses 6 consists of four lenses 11-14, the first two lenses of which 11 and 12 are menisci with convexities facing outward from each other, the second two lenses 13 and 14 are positive convex-concave lenses located along the beam: the first bulge in the direction of the image, the second bulge in the direction of the object.

The diaphragm 15 is placed between the two menisci 11 and 12.

The first group of lenses 5 and the second group of lenses 6 form an afocal optical system with a given conversion scale and a telecentric course of the input and output rays.

Menisci 11 and 12 are used to correct wavefront errors.

For such an optical scheme, the object is located at infinity, as it were, and its orthogonal projection in the transformed scale is observed in the image.

An additional light channel with a lens system 16 and a matrix photodetector 17 can be placed, as shown in Fig. 1, required for adaptive scanning control, for example, when rolling fingerprints.

In this case, the area of the object captured by the additional light channel can be significantly smaller than the entire working surface of the prism, but sufficient to control rolling.

However, in the case of a translucent mirror 56, Fig.10, the additional optical channel can be combined with the main optical channel of the lens system 4.

The tilt angle α1 of the optical axis of the main lens system 4 is selected from the conditions of total internal reflection at the glass-air interface, total internal reflection at the glass-water interface, total internal reflection at the glass-skin interface of the finger.

For the selected BK-4 prism glass (Nc = 1.5276), clean water (Nc = 1.3316), sea water (Nc = 1.33953), finger skin (Nc = 1.440), the angle of inclination of the main lens system was α1 = 63.5 °.

The angle of inclination α2 of the additional light channel can be determined from the condition of total internal reflection at the glass-air interface, α2> 40.89 °, that is, from the condition: 40.89 ° <α2 <α1 = 63.5 °.

The choice of the angle of inclination α1 = 63.5 ° eliminates the influence of moisture on the palms, fingers, etc. on the quality of scanned prints.

A smaller angle α1 has an advantage.

A soft optical coating with an optical refractive index greater than that of the finger skin can be applied to the working surface of prism 2 to improve image quality. The presence of a soft optical coating on the working surface of the prism does not affect the parameters of the optical scheme.

The optical unit 8 was created and designed as an afocal anamorphic system that satisfies the conditions of angular conjugation of the object and image at a given conversion scale and telecentricity for input and output rays, as well as the condition for correcting distortion in one vertical direction along the scan line.

In this case, the focal length of the first lens component satisfies the condition:

F1≥L / 2 · (cosα1 / tgβ),

where β is the half-angle of convergence of the rays after the first group of lenses;

L is the longitudinal size of the working field of the prism.

The angle β is chosen empirically as the maximum at which the calculations give a reliable qualitative result, about 13 °, that is, β≤13 °.

A larger angle has an advantage because it reduces the size.

Focal length of the second lens component:

F2 = m1

where m1 is the transverse image scale.

The optimal and maximum focal length value F0 of the entire optical system is determined from optimization calculations of the entire optical system, based on such characteristics as image distortion, point scattering energy circle, and functions of frequency-contrast characteristics for different points of the image field.

The degree of telecentricity of the input and output rays, the gradient of the image scale depend on the magnitude of the focal length F0.

With the focal length of the entire optical system tending to infinity, the condition for the constancy of the longitudinal and transverse image scales is fulfilled.

With the focal length of the entire optical system lying in the region of positive values, there is a positive perspective.

With the focal length of the entire optical system lying in the region of negative values, there is a negative perspective.

A positive or negative perspective leads to the fact that the oblique object in the form of a square is depicted by a trapezoid with a large base either above or below.

The choice and control of the focal length F0 of the entire optical system can be used to compensate for image distortions obtained by scanning fingerprints on the conical working surfaces of prisms.

One of the applications of the proposed device is the implementation of a palm scanner according to the method (RU 2168206 C1, classes: G 06 K 9/00, A 61 V 5/117, publication date 05/27/2001, priority 30/06/2000), in which there is a prism in the form a cylinder rotating about its axis for scanning palm prints, Fig. 8.

In this device, the compensating prism 32 is made with a vertical reflecting face 33, which rotates the optical axis by 90 °, a vertical mirror 35 behind the first lens component rotates the optical axis by another 90 °.

The focal length of the first lens component of two lenses is 144 mm, the focal length of the second lens component of four lenses is 68 mm, the total focal length is from 1500 mm to 2800 mm, the aperture was calculated at a value of 3.5, the image size is 36 mm, the angle of inclination of the linear matrix is 30 °.

The device, Fig. 8, has small dimensions and allows you to get high-quality palm prints with image distortion of not more than 1% and a resolution of 1000 dpi. Qualitative optical characteristics of the device are shown in Fig.9: a) - Frequency-contrast characteristics; b) - Diagrams of scattering points; c) - Schedule of distortion.

In the table. 1 gives the structural data of the optical circuit of the device.

The second application of the proposed device is a palm scanner, figure 10, with a fixed prism 51 and a movable lens unit 52, which has an additional three mirrors: two mirrors 53 and 54 after the first group of lenses and mirror 55 after the second group of lenses.

An additional optical channel is located below the main optical channel at a smaller angle of inclination of the optical axis and has three mirrors 56, 57, 58, a prism 59 glued from two rectangular prisms, a lens objective 16, and an array photodetector 17.

The device of FIG. 10 has the same optical parameters as the device of FIG.

The third application is a scanner for scanning fingerprints on a concave conical surface of the prism, Fig.11.

The conical prism 61 is fixedly mounted, the optical lens assembly 62 with a compensating prism 3, a linear array photodetector 7 and a illuminator 65 rotate around a common axis 66 by a predetermined angle, the axis of rotation is the axis of the working conical surface of the prism 61.

The focal length of the optical system of the device, Fig. 11, lies in the region of positive values F0 = 107 mm, which creates a direct perspective of 6% to the side when creating an image scan, which partially compensates for the trapezoidal scan of the image of the object, leading it to a view that is close to rectangular.

The focal length of the first lens component is F1 = 68 mm, the second is F2 = 35.2 mm, the longitudinal size of the object is L = 70 mm, and the image size is 19 mm.

For a better design arrangement, the optical lens assembly 62 further has a mirror 67 behind the first lens component and a mirror 68 behind the second lens component.

Table 1 Surface number The radius of the surface. Thick Refractive Index Dispersion Grade
glass An object Flat 150 1,530272 60.26 BK4 1 Flat 40 2 Flat 8.5 1,806276 25.35 TF10 3 -185.13 0.2 4 300.6 6 1,806276 25.35 TF10 5 Flat 103.8 6 17,378 7.07 1,612682 58.14 TK16 7 13.6 15.04 Aperture Flat 6.47 nine -16,368 6.86 1,612682 58.14 TK16 10 -18.97 55.7 eleven -644.2 7 1,806276 25.35 TF10 12 -88.12 0.1 thirteen 86.1 8.25 1,806276 25.35 TF10 14 322.8 72.8 Image Flat

Claims (17)

1. An optical device for scanning a skin pattern, comprising a illuminator having a matrix of light sources, an optical system having a sensor optical element with an angle of total internal reflection at the glass-water interface, and an optical lens system forming an optical beam defining an optical image of the skin imprint having the property of dual telecentricity and anamorphic image, satisfying the condition of angular conjugation of the planes of the object and the image, the photodetector, which differs in That the optical system for directly touch compensating optical element comprises a prism in the form of a wedge, wherein the compensating prism exit face perpendicular to the optical axis of the lens system; each element from the matrix of light sources creates a flat beam of light, for example, using a bifocal lens, a prism with double internal reflection is introduced into the illuminator, forming a total light stream from the matrix of light sources directed in the direction working for the lens system, having the form of a wedge, one of the surfaces of the wedge has a raster surface, the touch optical element can have a convex, flat or concave working surface and is intended for scanning during rotation or linearly m movement relative to the compensating prism, the optical lens system and the photodetector, the illuminator being associated with relative movement either with the touch optical element or with the compensating prism, the lens system and the photodetector; the optical lens system consists of two positive lens components forming an afocal dual telecentric optical system, the first lens component consists of two plane-convex lenses, the first lens is convex towards the image space, the second lens is convex towards the object space, the second lens component consists consistently of two menisci and two convex-concave lenses, the first meniscus is convex towards the object space, the second meniscus is facing you uklostyu toward the image space, the first convexo-concave lens is convex toward the image space, the second convex-concave lens is convex toward the object space. 2. The device according to claim 1, characterized in that each bifocal lens of the matrix of light sources has an input for the light beam spherical surface directed by concavity towards the light source, and an output cylindrical surface facing convex towards the object. 3. The device according to claim 1, characterized in that the illuminator comprises an additional prism having a face input to the light beam and an internal reflective face, creating, together with the prism with double internal reflection, a five-fold internal reflection of the light flux. 4. The device according to claim 1, characterized in that the illuminator contains an additional prism in the form of a wedge having a face input for the light flux, creating together with a prism with double internal reflection a four-fold internal reflection of the light flux. 5. The device according to claim 3 or 4, characterized in that in the illuminator an additional prism has an input cylindrical surface. 6. The device according to claim 1, characterized in that in the illuminator the raster surface is made in the form of a set of a large number of narrow inclined mirror faces so that the raster surface has a sawtooth profile in cross section. 7. The device according to claim 1, characterized in that in the illuminator, the raster surface of the prism with double internal reflection can be made in the form of a directional or non-directional rough surface. 8. The device according to claim 1 or 7, characterized in that in the illuminator a prism with double internal reflection may have two rough surfaces with directional or non-directional roughness. 9. The device according to claim 1, or 2, or 7, or 8, characterized in that the touch optical element is made in the form of a cylinder and is designed to scan the pattern of skin lines by rotating it about its own axis. 10. The device according to claim 1 or 9, characterized in that the compensating prism is made with an inclined reflective face that creates a single internal reflection for the working light beam. 11. The device according to claim 1, or 9, or 10, characterized in that it contains an additional mirror between two lens components for refracting the optical axis. 12. The device according to any one of claims 1 to 8, characterized in that the sensor optical element is made in the form of a prism with a flat working surface and is intended for scanning by linear movement of the lens unit and photodetector along the working plane of the prism. 13. The device according to claim 1 or 12, characterized in that it contains an additional optical channel containing a lens system, such as a lens and a photodetector, designed to control scanning, for example, when rolling fingers. 14. The device according to claim 1, or 12, or 13, characterized in that it further comprises a first and second mirror between the first and second lens components and a third mirror between the lens system and the photodetector. 15. The device according to any one of claims 1 or 12-14, characterized in that the additional optical channel contains three mirrors and two glued rectangular prisms, and in the case of combining the additional optical channel with the lens system, the first of the mirrors may be translucent. 16. The device according to any one of claims 1 to 8, or 2, or 3, or 4, or 6, or 7, characterized in that the sensor optical element is made in the form of a truncated cone with a concave conical working surface and is intended for scanning by rotation of the compensating prism, lens unit and photodetector relative to the axis of the conical sensor optical element. 17. The device according to claim 1 or 16, characterized in that it further comprises two mirrors: the first after the first lens component and the second after the second lens component.

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