CN108241833A - Biometric feature recognition device - Google Patents

Abstract

The invention provides a biological characteristic identification device, which comprises a light source, a light guide element, an image acquisition element and a first collimator. The light source is adapted to provide a light beam. The light guide element is positioned on the transmission path of the light beam. The image capturing element is located below the light guide element and has a plurality of pixel regions. The first collimator is located between the light guide element and the image capturing element, wherein the first collimator comprises a light transmitting element and a light absorbing layer. The light-transmitting element is provided with a first surface and a second surface. The light absorbing layer is disposed on the first surface and the second surface and has a plurality of first openings exposing the first surface and a plurality of second openings exposing the second surface. The first opening and the second opening are overlapped in the pixel area, and the aperture of the second opening is smaller than that of the first opening. The light absorption layer is used for absorbing the light beams with large angles so as to collimate the light beams transmitted to the image capturing element and improve the image capturing quality of the image capturing element. Therefore, the biometric identification device can have good identification capability.

Description

biometric identification device

technical field

The invention relates to a biometric identification device.

Background technique

The types of biometric identification include face, voice, iris, retina, vein, fingerprint and palmprint recognition, etc. Since each person's fingerprint is unique, and the fingerprint is not easy to change with age or health status, the fingerprint identification device has become the most popular biometric identification device at present. According to different sensing methods, fingerprint recognition devices can be classified into optical type and capacitive type. When the capacitive fingerprint recognition device is assembled in an electronic product (such as a mobile phone, a tablet computer), a protective element (cover lens) is often provided above the capacitive fingerprint recognition device. Generally speaking, additional processing (such as drilling or thinning) of the protection element is required, so that the capacitive fingerprint recognition device can sense the capacitance or electric field change caused by finger touch.

Compared with the capacitive fingerprint recognition device, the optical fingerprint recognition device captures the light that easily penetrates the protective element for fingerprint recognition, and does not require additional processing of the protective element, so it is more convenient to combine with electronic products.

An optical fingerprint identification device usually includes a light source, an image capture element and a light-transmitting element. The light source is used to emit light beams to irradiate fingers pressed on the light-transmitting element. The fingerprint of the finger is composed of many irregular convex lines and concave lines. The light beams reflected by the convex and concave grooves will form a bright and dark fingerprint image on the receiving surface of the image capturing element. The image capturing component can convert the fingerprint image into corresponding image information, and input the image information to the processing unit. The processing unit can use an algorithm to calculate the image information corresponding to the fingerprint, so as to identify the identity of the user. However, in the above-mentioned image capturing process, the light beam reflected by the fingerprint is likely to be scattered and transmitted to the image capturing element, resulting in poor image capturing quality and affecting the identification result.

Contents of the invention

The invention provides a biometric identification device.

According to an embodiment of the present invention, the biometric identification device includes a light source, a light guide element, an image capture element, and a first collimator. The light source is adapted to provide a light beam. The light guiding element is located on the transmission path of the light beam. The image capture element is located under the light guide element and has a plurality of pixel areas. The first collimator is located between the light guide element and the image capture element, wherein the first collimator includes a light-transmitting element and a light-absorbing layer. The light-transmitting element has a first surface and a second surface located between the first surface and the image capturing element. The light absorbing layer is disposed on the first surface and the second surface and has a plurality of first openings exposing the first surface and a plurality of second openings exposing the second surface, wherein the first openings and the second openings overlap the pixel area , and the aperture of the second opening is smaller than the aperture of the first opening.

In the biometric identification device according to the embodiment of the present invention, the light guide element has a light exit portion and a light entrance portion connected to the light exit portion. The light source and the image capturing element are both located under the light emitting part. The light incident part is located between the light source and the light exit part.

In the biometric authentication device according to the embodiment of the present invention, the light source is located at the side of the light guide element.

In the biometric identification device according to the embodiment of the present invention, a plurality of microstructures are formed on the surface of the light guide element facing the first collimator. Microstructures protrude or indent on the surface.

In the biometric authentication device according to the embodiment of the present invention, the refractive index of the light-transmissive element falls within the range of 1.3 to 1.7.

In the biometric identification device according to an embodiment of the present invention, the ratio of the aperture of each first opening to the height of the light-transmitting element falls within a range of 2-20.

In the biometric identification device according to an embodiment of the present invention, the ratio of the aperture of each second opening to the height of the light-transmitting element falls within a range of 2-20.

In the biometric identification device according to an embodiment of the present invention, the light-transmitting element further has a sidewall connecting the first surface and the second surface, and the light-absorbing layer is further disposed on the sidewall.

In the biometric identification device according to the embodiment of the present invention, the biometric identification device further includes a cover plate, wherein the light guide element is located between the cover plate and the first collimator.

In the biometric identification device according to the embodiment of the present invention, the biometric identification device further includes a second collimator. The second collimator is located between the light guiding element and the first collimator. The second collimator includes a plurality of prisms, and the apex angles of the prisms respectively point to the light guide element.

Based on the above, in the biometric identification device according to the embodiment of the present invention, the large-angle light beams acting on the object to be identified and passing through the light guide element are absorbed by adjusting the apertures of the first opening and the second opening, so as to transfer to the image The collimation of the light beam of the capturing element improves the imaging quality of the image capturing element. Therefore, the biometric identification device can have good identification capability.

Description of drawings

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain principles of the invention.

FIG. 1 is a schematic cross-sectional view of a biometric identification device according to an embodiment of the present invention;

Fig. 2 is an enlarged view of the light guide element in Fig. 1;

3A is a schematic top view of the first collimator in FIG. 1;

Figure 3B is a schematic bottom view of the first collimator in Figure 1;

Fig. 4 is a schematic cross-sectional view of the first collimator, the image capture element and the circuit board in Fig. 1;

Fig. 5 is an enlarged view of the light guide element and the second collimator in Fig. 1;

FIG. 6 is a schematic cross-sectional view of a biometric identification device according to another embodiment of the present invention.

Explanation of reference numbers:

10: object to be identified;

100, 100A: biometric identification device;

110: light source;

112: light emitting element;

120, 120A: light guide element;

122: light emitting part;

124: light incident part;

130: image capture component;

132: charge coupled device;

140: a first collimator;

142: light-transmitting element;

144: light absorbing layer;

150: circuit board;

160: cover plate;

170: a second collimator;

172: prism;

B, B', B1', B2': Beam;

BA: bottom angle;

C: concave;

H: height;

M: microstructure;

O1: first opening;

O2: second opening;

PR: pixel area;

S, S': surface;

S1: the first reflective surface;

S2: second reflective surface;

S1421: the first surface;

S1422: the second surface;

S1423: side wall surface;

TA: top angle;

WO1, WO2: aperture.

Detailed ways

Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used in the drawings and description to refer to the same or like parts.

FIG. 1 is a schematic cross-sectional view of a biometric identification device according to an embodiment of the present invention. Referring to FIG. 1 , the biometric identification device 100 is, for example, a fingerprint identification device for identifying the fingerprint of the object 10 to be identified, but not limited thereto. In another embodiment, the biometric identification device 100 can also be used to identify veins, palm prints, or a combination of at least two of fingerprints, veins, and palm prints.

The biometric identification device 100 includes a light source 110 , a light guide element 120 , an image capture element 130 and a first collimator 140 .

The light source 110 is adapted to provide a beam B of light. The light source 110 may be an invisible light source or a visible light source. That is to say, the light beam B can be invisible light (for example: infrared light) or visible light (for example: red light, blue light, green light or a combination thereof). Alternatively, the light source 110 may be a combination of an invisible light source and a visible light source. For example, the light source 110 may include a plurality of light emitting elements 112 . The light emitting element 112 can be a light emitting diode or other suitable types of light emitting elements. FIG. 1 schematically shows two light emitting elements 112 , and the two light emitting elements 112 are located on opposite sides of the image capturing element 130 . However, the number and configuration of the light emitting elements 112 can be changed according to requirements, and are not limited thereto.

The light guide element 120 is located on the transmission path of the light beam B, and is suitable for guiding the light beam B provided by the light source 110 to the object 10 to be identified. For example, the material of the light guide element 110 can be glass, polycarbonate (PC), polymethyl methacrylate (PMMA) or other suitable materials. In this embodiment, the light source 110 and the image capture element 130 are located on the same side of the light guide element 120 . The biometric identification device 100 further includes a circuit board 150 . The light source 110 is disposed on the circuit board 150 and electrically connected to the circuit board 150 . The light guide element 120 has a light exit portion 122 and at least one light incident portion 124 connected to the light exit portion 122 . The light source 110 and the image capture element 130 are both located under the light exit portion 122 , and the light source 110 is located beside the image capture element 130 . The light incident portion 124 is located between the light source 110 and the light exit portion 122 . In detail, the light incident portion 124 can be fixed on the circuit board 150 , and the light incident portion 124 has a depression C. As shown in FIG. The recess C and the circuit board 150 enclose a space for accommodating the light source 110 . In another embodiment, at least one of the light incident portion 124 and the circuit board 150 may have a recess (not shown) to accommodate the light source 110 . In yet another embodiment, the light incident portion 124 and the circuit board 150 can be fixed together by a fixing mechanism (not shown) or an adhesive layer (not shown, such as optical glue). In yet another embodiment, the light incident portion 124 may be fixed on the light source 110 by an adhesive layer (not shown, such as optical glue), and the light incident portion 124 may not be in contact with the circuit board 150 . FIG. 1 schematically shows two light incident portions 124 , and the two light incident portions 124 are located on opposite sides of the light exit portion 122 . However, the number and arrangement of the light incident portions 124 can be changed according to requirements, and are not limited thereto.

FIG. 2 is an enlarged view of the light guide element in FIG. 1 . Referring to FIG. 1 and FIG. 2 , the light beam B emitted from the light source 110 enters the light guide element 120 from the light incident portion 124 , and the light beam B can be transmitted to the light output portion 122 through the light incident portion 124 . The surface S of the light guide element 120 facing the first collimator 140 may optionally be formed with a plurality of microstructures M (not shown in FIG. 1 , please refer to FIG. 2 ). The microstructure M is adapted to change the transmission direction of the light beam B, so that the light beam B reflected by the microstructure M exits the light emitting portion 122 vertically or nearly vertically. As shown in FIG. 2 , the microstructure M may protrude from the surface S and may have a first reflective surface S1 and a second reflective surface S2 . The first reflective surface S1 and the second reflective surface S2 are connected to each other, wherein the first reflective surface S1 and the second reflective surface S2 are inclined relative to the surface S, and the inclination directions of the first reflective surface S1 and the second reflective surface S2 are opposite. In one embodiment, the microstructure M, the light exit portion 122 and the light entrance portion 124 can be integrally formed, but not limited thereto. In another embodiment, the microstructure M, the light exit portion 122 and the light entrance portion 124 can be manufactured separately, and then fixed together by a connection mechanism or an adhesive layer (eg, optical glue). Alternatively, the microstructure M can also be recessed on the surface S. As shown in FIG. Specifically, the microstructure M may be a depression formed on the surface S. As shown in FIG. In addition, the number and distribution of the microstructures M can be changed according to different requirements, and are not limited to the number and distribution shown in FIG. 2 .

The surface S' of the light emitting part 122 outputting the light beam B is opposite to the surface S on which the microstructure M is formed. In one embodiment, the surface S' may be a pressing surface for pressing the object 10 to be identified. Under the framework of the surface S' being the pressing surface, as shown in FIG. 2, the light beam B from the light source 110 passes through the light incident portion 124 and the light exit portion 122 in sequence, and undergoes total internal reflection (Total Internal Reflection, TIR) on the surface S'. , and then reflected by the second reflective surface S2 and the first reflective surface S1 in sequence, and exit the surface S′ vertically or nearly vertically.

Alternatively, as shown in FIG. 1 , the biometric identification device 100 may further include a cover plate 160 for pressing the object 10 to be identified. The cover plate 160 is located above the light guide element 120 , and the light guide element 120 is located between the cover plate 160 and the first collimator 140 . The cover plate 160 may be a cover lens of an electronic product to be assembled (such as a touch panel or a touch display panel), but is not limited thereto. In one embodiment, the cover plate 160 and the light guide element 120 can be fixed together by a connection mechanism or an adhesive layer (eg, optical glue), but not limited thereto. In the case of fixing the cover plate 160 and the light guide element 120 with an adhesive layer, the refractive index of the adhesive layer, the cover plate 160 and the light guide element 120 can be the same or similar to reduce interface reflection, thereby improving the light utilization of the biometric identification device 100 efficiency and/or image quality. However, in other embodiments, the refractive indices of the adhesive layer, the cover plate 160 and the light guide element 120 may also be different. Under the structure of the cover plate 160 , the light beam B from the light source 110 sequentially passes through the light incident portion 124 , the light output portion 122 and the cover plate 160 , and undergoes total internal reflection on the surface of the cover plate 160 on which the object 10 to be identified is pressed. The light beam B' that has been acted on (for example: diffused) by the object to be identified 10 passes through the cover plate 160 and the light emitting portion 122 in sequence and is delivered to the surface S. A part of the light beam B' transmitted to the surface S will be reflected by the surface S, and then transmitted toward the surface of the cover plate 160 for pressing the object 10 to be identified. On the other hand, another part of the light beam B' delivered to the surface S exits the light guide element 120 from the surface S.

The image capture element 130 is located under the light guide element 120 and has, for example, a plurality of pixel (pixel) regions PR (shown in FIG. 4 ) arranged in an array to receive the light beam B' acting on the object 10 to be identified, and then obtain the object to be identified. Image of object 10. In this embodiment, the image capture device 130 includes, for example, a plurality of charge-coupled devices (Charge-Coupled Device, CCD) 132 (shown in FIG. 4 ). The CCD 132 is disposed on the circuit board 150 and electrically connected to the circuit board 150 . The region where the CCD 132 is located is the pixel region PR of the image capture device 130 . In another embodiment, the image capture device 130 may include a plurality of complementary metal oxide semiconductors (Complementary Metal Oxide Semiconductor, CMOS), and the region where the CMOS is located is the pixel region PR of the image capture device 130 .

The first collimator 140 is located between the light guide element 120 and the image capture element 130, and the first collimator 140 is located on the transmission path of the light beam B' after the object 10 to be identified 10 is acted on. For example, the first collimator 140 can be disposed on the image capture element 130, and the first collimator 140 and the image capture element 130 can be fixed on the first collimator 140 and the image capture element 130 by a connection mechanism or an adhesive layer (such as: optical glue). together, but not limited to.

FIG. 3A is a schematic top view of the first collimator in FIG. 1 . FIG. 3B is a schematic bottom view of the first collimator in FIG. 1 . FIG. 4 is a schematic cross-sectional view of the first collimator, the image capture element and the circuit board in FIG. 1 . Referring to FIG. 1 , FIG. 3A to FIG. 4 , the first collimator 140 includes a light-transmitting element 142 and a light-absorbing layer 144 . The transparent element 142 has a first surface S1421, a second surface S1422 located between the first surface S1421 and the image capture element 130, and a sidewall surface S1423 connecting the first surface S1421 and the second surface S1422. The light absorbing layer 144 is disposed on the first surface S1421 and the second surface S1422 and has a plurality of first openings O1 exposing the first surface S1421 and a plurality of second openings O2 exposing the second surface S1422, wherein the first openings O1 It overlaps with the second opening O2 in the pixel region PR, so that the light beam passing through the first opening O1 and the second opening O2 in sequence can be transmitted to the image capture device 130 (as shown by the light beam B2 ′ in FIG. 4 ). In addition, the aperture WO2 of the second opening O2 is smaller than the aperture WO1 of the first opening O1.

In this embodiment, the size of the pixel region PR may be slightly larger than the aperture WO1 of the first opening O1 and the aperture WO2 of the second opening O2 , but it is not limited thereto. In addition, the light-absorbing layer 144 can be further disposed on the sidewall surface S1423 of the light-transmitting element 142 , so as to prevent the light beam transmitted in the light-transmitting element 142 from being emitted from the sidewall surface S1423 . However, in another embodiment, the light absorbing layer 144 may not be disposed on the side wall surface S1423 of the light transmitting element 142 .

When the refractive index of the light transmission medium (for example: air or optical glue) between the light guiding element 120 and the first collimator 140 is different from the refractive index of the light transmitting element 142, the light beam B' ( The light beam B1 ′ incident on the light-transmitting element 142 at a large angle and the light beam B2 ′ incident on the light-transmitting element 142 at a small angle enter the light-transmitting element 142 through refraction on the first surface S1421 of the light-transmitting element 142 . Therefore, the arrangement of the light-transmitting element 142 helps to narrow the angle at which the light beam B' enters the first collimator 140, so that more light beams B' can be transmitted to the image capturing element 130.

The light-transmitting element 142 can be made of glass, polycarbonate (PC), polymethyl methacrylate (PMMA) or other suitable materials. The material of the light-absorbing layer 144 can be, for example, silicon-based or acrylic-based materials containing light-absorbing materials (eg, carbon). In this way, even if the light beam B1 ′ incident on the light-transmitting element 142 at a large angle and the light beam B2 ′ incident on the light-transmitting element 142 at a small angle both enter the light-transmitting element 142 through the first opening O1, the light beam located on the second surface S1422 can still be utilized. The light absorbing layer 144 absorbs the light beam B1 ′ incident on the light-transmitting element 142 at a large angle, and only allows the light beam B2 ′ incident on the light-transmitting element 142 at a small angle to pass through and transmit to the image capturing element 130 . In the case where the pixel regions PR are densely arranged, by making the aperture WO2 of the second opening O2 smaller than the aperture WO1 of the first opening O1, the light-absorbing area of the light-absorbing layer 144 on the second surface S1422 can be increased, thereby helping to avoid large The light beam incident on the light-transmitting element 142 at an angle passes through the second opening O2 not directly below (the second opening O2 obliquely below) and is transmitted to the image capturing element 130 .

Whether the light beam entering the first collimator 140 is absorbed by the light absorbing layer 144 on the second surface S1422 may depend on the aperture WO1 of the first opening O1, the aperture WO2 of the second opening O2, the height H of the light-transmitting element 142 and the light beam The refraction angle of B′ on the first surface S1421 of the light-transmitting element 142 (determined by the incident angle of the light beam B′ and the refractive index of the light-transmitting element 142 ), etc. When the height H of the light-transmitting element 142 is constant, the larger the aperture WO1 of the first opening O1 and the aperture WO2 of the second opening O2 are, the larger the angle range of the beam B' received by the image capturing element 130 is. When the aperture WO1 of the first opening O1 and the aperture WO2 of the second opening O2 are constant, the larger the height H of the transparent element 142 is, the smaller the angular range of the light beam B' received by the image capturing element 130 is. When the aperture WO1 of the first opening O1, the aperture WO2 of the second opening O2, and the height H of the light-transmitting element 142 are constant values, the larger the refraction angle of the beam B' (that is, the larger the incident angle), the more May be absorbed by light absorbing layer 144. In this embodiment, the refractive index of the light-transmissive element 142 is greater than 1, and falls within a range of 1.3 to 1.7, for example. In addition, the ratio of the diameter WO1 of each first opening O1 (which is also the diameter WO2 of the second opening O2 ) to the height H of the light-transmitting element 142 falls within a range of 2-20. The ratio of the diameter WO2 of each second opening O2 to the height H of the transparent element 142 falls within a range of 2-20. However, the refractive index of the light-transmitting element 142, the ratio of the aperture WO1 of the first opening O1 to the height H of the light-transmitting element 142, and the ratio of the aperture WO2 of the second opening O2 to the height H of the light-transmitting element 142 may depend on different design requirements ( For example: the pitch of the image capture device 130 is changed, not limited to the above.

The light-absorbing layer 144 is used to absorb the large-angle light beam (for example: light beam B1') that is acted on by the object to be identified 10 and passes through the light guide element 120, so that only a specific angle of light beam (a small-angle incident light beam, such as: light beam B2') can be transmitted to the image capture device 130 . By appropriately adjusting the aperture WO1 of the first opening O1 and the aperture WO2 of the second opening O2, the light beam B' passing through the first collimator 140 can be incident on the image capture device 130 at an angle of 0 degrees or close to 0 degrees. . In other words, the first collimator 140 helps to collimate the light beam transmitted to the image capture device 130 . In this way, it not only helps to filter out stray light, but also helps to avoid the mutual interference of the light beams B' output from different second openings O2, so as to improve the image quality of the image capturing element 130. Therefore, the biometric identification device 100 can have good identification capability. 3A and 3B schematically show that the shapes of the first opening O1 and the second opening O2 are circular, but not limited thereto. In other embodiments, the shapes of the first opening O1 and the second opening O2 may also be triangles, quadrilaterals, pentagons or other polygons.

According to different requirements, the biometric identification device 100 may also include other components. For example, the biometric identification device 100 may further include a second collimator 170 . The second collimator 170 is located between the light guide element 120 and the first collimator 140, and the second collimator 170 is located on the transmission path of the beam B' after the object 10 to be identified is acted upon. For example, the second collimator 170 can be disposed on the surface S, and the light guide element 120 and the second collimator 170 can be fixed together by a connection mechanism or an adhesive layer (for example: optical glue), but not This is the limit.

The second collimator 170 is suitable for pre-collimating the beam B' before the beam B' passes through the first collimator 140, so as to converge the divergence angle of the beam B'. In this way, the probability of the beam B' subsequently passing through the first collimator 140 can be increased. Fig. 5 is an enlarged view of the light guide element and the second collimator in Fig. 1 . Referring to FIG. 1 and FIG. 5 , the second collimator 170 may include a plurality of prisms 172 , and the apex angles TA of the prisms 172 are respectively directed to the light guide element 120 . In this embodiment, the two base angles BA of each prism 172 are the same. However, the apex angle TA and the base angle BA of the prism 172 can be changed according to different requirements, and are not limited thereto.

FIG. 6 is a schematic cross-sectional view of a biometric identification device according to another embodiment of the present invention. The biometric identification device 100A in FIG. 6 is similar to the biometric identification device 100 in FIG. 1 , and the biometric identification device 100A has functions and advantages similar to those of the biometric identification device 100 , which will not be repeated here. The difference between the biometric identification device 100A in FIG. 6 and the biometric identification device 100 in FIG. 1 lies in the location of the light source 110 . In detail, in the embodiment of FIG. 6 , the light source 110 is located at the side of the light guide element 120A. Under this framework, the light guide element 120A is, for example, plate-shaped, and the light incident portion 124 of the light guide element 120 in FIG. 1 can be omitted from the light guide element 120A.

To sum up, in the biometric identification device according to the embodiment of the present invention, the large-angle light beams acting on the object to be identified and passing through the light guide element are absorbed by adjusting the apertures of the first opening and the second opening, so as to transmit The collimation of the light beam to the image capture element improves the image quality of the image capture element. Therefore, the biometric identification device can have good identification capability.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. scope.

Claims (10)

1. A biometric identification device, characterized in that, comprising: a light source adapted to provide a beam of light; a light guide element located on the transmission path of the light beam; an image capture element, located below the light guide element and having a plurality of pixel regions; and A first collimator, located between the light guide element and the image capture element, wherein the first collimator includes: a light-transmitting element having a first surface and a second surface located between the first surface and the image capturing element; and A light-absorbing layer configured on the first surface and the second surface, and the light-absorbing layer has a plurality of first openings exposing the first surface and a plurality of second openings exposing the second surface Openings, wherein the plurality of first openings and the plurality of second openings overlap the pixel area, and the apertures of the plurality of second openings are smaller than the apertures of the plurality of first openings. 2. The biometric identification device according to claim 1, wherein the light guide element has a light exit portion and a light entrance portion connected to the light exit portion, and the light source and the image capture element are co-located Below the light emitting part, the light entering part is located between the light source and the light emitting part. 3. The biometric identification device according to claim 1, wherein the light source is located at a side of the light guide element. 4. The biometric identification device according to claim 1, wherein a plurality of microstructures are formed on the surface of the light guide element facing the first collimator, and the plurality of microstructures are protruding or concave. into the surface. 5 . The biometric identification device according to claim 1 , wherein the refractive index of the light-transmitting element falls within the range of 1.3 to 1.7. 6 . The biometric identification device according to claim 1 , wherein a ratio of an aperture of each of the plurality of first openings to a height of the light-transmitting element falls within a range of 2-20. 7 . The biometric identification device according to claim 1 , wherein a ratio of an aperture of each of the plurality of second openings to a height of the light-transmitting element falls within a range of 2-20. 8. The biometric identification device according to claim 1, wherein the light-transmitting element further has a side wall surface connecting the first surface and the second surface, and the light-absorbing layer is also arranged on the on the side wall. 9. The biometric identification device according to claim 1, further comprising: A cover plate, wherein the light guide element is located between the cover plate and the first collimator. 10. The biometric identification device according to claim 1, further comprising: The second collimator is located between the light guide element and the first collimator, the second collimator includes a plurality of prisms, and the apex angles of the plurality of prisms are respectively directed to the light guide element.