WO2019134059A1

WO2019134059A1 - Optical fingerprint recognition system

Info

Publication number: WO2019134059A1
Application number: PCT/CN2018/000023
Authority: WO
Inventors: 林哲玄; 萧嘉源; 叶俊宏
Original assignee: 敦捷光电股份有限公司
Priority date: 2018-01-04
Filing date: 2018-01-22
Publication date: 2019-07-11
Also published as: CN108009533A

Abstract

An optical fingerprint recognition system (20), which provides the surface of a light guide panel (21) as a fingerprint sensing area (211) to be pressed with a finger, at the same time, provides a collimated optical signal and introduces the optical signal into the light guide panel (21) for transmission by means of total internal reflection effect, and by utilizing the damage caused by the pressing of the finger to the total internal reflection of the optical signal in the light guide panel (21), allows a photosensitive component (24) to detect a waveform change of the optical signal and process into a fingerprint image. As such, when the optical fingerprint recognition system (20) is integrated into a display panel, the photosensitive component (24) is concealed in the rear surface of the display panel and needs not to receive a fingerprint-reflected light, thus obviating the problem with transmittance; moreover, the fingerprint sensing area (211) can be implemented over the entire or a partial area of the light guide panel (21), thus not only allowing increased flexibility in use, but also satisfying aesthetic demands of consumers on product appearance.

Description

Optical fingerprint identification system

Technical field

The invention relates to a fingerprint identification technology, in particular to an optical fingerprint identification system which utilizes the total total reflection effect of light for sensing and identification.

Background technique

Fingerprint recognition is a kind of biometric recognition technology, which uses the unique fingerprint information on the human finger to identify it, and its advantages in terms of security and convenience are widely used; for example, today's smart phones are almost all Added fingerprint recognition function to provide fingerprint encryption and fingerprint unlocking.

An optical fingerprint identification system 10, with reference to FIG. 1, a pressure plate 12, a light diffusion plate 13 and a photosensitive element 11 are sequentially disposed from top to bottom, and a plurality of light sources 14 are disposed around the photosensitive element 11. The platen 12 has a plate surface 121 that can be pressed by a finger. The light diffusing plate 13 guides the incident light emitted from the light source 14 to the pressing plate 12, and has a through hole 131 through which the reflected light passes. When the incident light is projected by the light diffusing plate 13 to the finger A, it is reflected by the through hole 131 to the photosensitive element 11 below. Since the peak of the fingerprint reflects the light, the trough absorbs the light. Therefore, the reflected light forms a contrast stripe, allowing the photosensitive element 11 to achieve fingerprint recognition.

At present, combining the fingerprint recognition function with the display function of the display panel is a hot topic that the industry is actively studying. If the fingerprint identification system is integrated or integrated into the display panel, if the relevant components of the fingerprint recognition are disposed above the display panel, since the photosensitive element based on the silicon wafer is opaque, it will be exposed outside the display panel. However, the problem of penetration under the display panel may not be able to receive the reflected light of the fingerprint well, thereby affecting the accuracy of fingerprint recognition. Therefore, there are certain restrictions on the integration of the fingerprint identification system into the display panel, and it is difficult to not interfere with the design of the product.

Therefore, there is a need to develop an optical fingerprint identification system that can be well integrated into the display panel so that the photosensitive elements are not exposed to meet the appearance requirements of the product, which is not only different from the prior art structure, but also can effectively overcome Its various deficiencies; its specific structure and implementation will be detailed below.

Summary of the invention

In view of the above problems, the main object of the present invention is to provide an optical fingerprint identification system that allows an optical signal to be transmitted through a light-conducting panel through an internal total reflection effect, thereby causing an optical signal to be totally reflected in the light guide panel by finger pressing. The destruction to achieve the role of fingerprint recognition.

Another object of the present invention is to provide an optical fingerprint identification system, which can conceal the photosensitive element on the back side of the display panel without being exposed, and at the same time, the fingerprint sensing area can be disposed in all or part of the light guide panel, preferably It meets the various needs of consumers for the appearance and flexibility of the product.

Therefore, in order to achieve the above object, the present invention provides an optical fingerprint identification system, which mainly comprises a light guide panel, a light source, a signal amplifier and a photosensitive element. The surface of the light guide panel has a fingerprint sensing area for pressing by a finger, and the light guiding panel is provided with a first light guiding portion and a second light guiding portion respectively at an light incident end and a light exit end. . The light source is adjacent to the first light guiding portion and provides at least one optical signal, and the optical signal is introduced into the light guiding panel via the first light guiding portion and transmitted by the total total reflection effect in the light guiding panel, and then through the second guiding The light department is exported. The signal amplifier is adjacent to the second light guiding portion, and receives the optical signal derived by the second light guiding portion, and amplifies the optical signal and then derives the optical signal. The photosensitive element is adjacent to the signal amplifier, and receives the optical signal derived by the signal amplifier, and processes the optical signal into a fingerprint image, thereby achieving the purpose of fingerprint recognition.

According to an embodiment of the invention, wherein the fingerprint sensing area may be all or a partial area of the surface of the light guiding panel.

According to an embodiment of the invention, the light guiding panel is disposed above a display panel.

According to an embodiment of the invention, the light guiding panel is attached to the display panel by coating optical glue or dispensing.

According to an embodiment of the invention, the light source may be a collimated light source or a non-collimated light source.

According to an embodiment of the invention, wherein the light source may be a laser, a vertical cavity laser (VCSEL) or a combination of a non-collimated light source and a secondary optical element.

According to an embodiment of the invention, wherein the secondary optical element may be selected from the group consisting of a parabolic surface concentrating mirror, a compound parabolic concentrating mirror (CPC), a lens, a prism, a Fresnel lens, and combinations thereof.

According to an embodiment of the invention, wherein the wavelength of the optical signal is between 380 and 1400 nanometers (nm).

According to an embodiment of the invention, wherein an angle between the optical signal and a normal to a surface or a bottom surface of the light guide panel is greater than arcsin when the optical signal travels within the light guide panel n ₀ /n ₂ ) and arcsin(n ₁ /n ₂ );

Where n ₀ is the refractive index of the surface of the light guiding panel;

n ₁ is the refractive index of the bottom surface of the light guide panel; and

n ₂ is the refractive index of the light guide panel.

According to an embodiment of the invention, the first light guiding portion, the second light guiding portion and the light guiding panel may be an integrated structure.

According to an embodiment of the invention, the first light guiding portion and the second light guiding portion may be separately disposed with respect to the light guiding panel.

According to an embodiment of the invention, the surface of the light guiding panel forms a plating film, the coating film can be penetrated by a visible light, and the light of the remaining wavelength band is reflected.

According to an embodiment of the invention, wherein the first light guiding portion and the second light guiding portion may be in the form of a mirror or an optical fiber.

According to an embodiment of the invention, wherein the signal amplifier may be in the form of a mirror.

According to an embodiment of the invention, the lens and the signal amplifier further comprise a lens, a prism film, an angular filter, a polarization splitting prism (PBS), and a beam splitter ( BS) or a combination thereof.

According to an embodiment of the invention, wherein the angle filter may be a vertical type or a tilt type grating filter.

According to an embodiment of the invention, wherein the grating filter is a single layer structure composed of a plurality of layers of the first material film being spaced apart.

According to an embodiment of the present invention, the grating filter is a single layer structure composed of a plurality of layers of a first material film and a plurality of layers of a second material film.

According to an embodiment of the present invention, the grating filter is a multilayer structure composed of a plurality of layers of a first material film and a plurality of layers of a second material film, and the different layers of the multilayer structure are The first material film is aligned or staggered.

According to an embodiment of the invention, the photosensitive elements are placed in parallel or obliquely with respect to the light guiding panel.

According to an embodiment of the present invention, at least one prism (Prism) is further included between the first light guiding portion and the light source and/or between the second light guiding portion and the signal amplifier, and the prism It is a fixed or rotatable prism.

According to the optical fingerprint identification system provided by the present invention, the internal total reflection effect of the optical signal in the light guide panel can be utilized, and the fingerprint image can be obtained by detecting the waveform change of the optical signal, and when the optical fingerprint identification system and display When the panel is integrated, the photosensitive element can be concealed on the back side of the display panel, and the problem of insufficient visibility can be affected, which can affect the design of the product appearance, and at the same time, a regional or comprehensive fingerprint feeling can be designed. The measurement area allows users to use the fingerprint recognition function more flexibly and conveniently.

The details, technical contents, features, and effects achieved by the present invention will become more apparent from the detailed description of the embodiments. The object, technical content, features and effects achieved by the present invention will become more apparent from the detailed description of the embodiments.

DRAWINGS

1 is a cross-sectional view of an optical fingerprint recognition system provided by the prior art.

2 is a cross-sectional view of an optical fingerprint recognition system according to an embodiment of the present invention.

3A-3C are schematic diagrams showing the use of different secondary optical elements and non-collimated light sources in an optical fingerprint identification system according to an embodiment of the present invention.

FIG. 3D is a schematic diagram of a combination of a prism and a non-collimated light source in an optical fingerprint identification system according to an embodiment of the present invention.

4A-4D are schematic diagrams showing the use of a lens, a prism film, an angle filter, and a combination of a prism film and an angle filter in a photosensitive element in an optical fingerprint identification system according to an embodiment of the present invention.

5A-5C are schematic diagrams of using different angle filters in a photosensitive element in an optical fingerprint identification system according to an embodiment of the present invention.

FIG. 5D to FIG. 5F are schematic diagrams showing the use of a combination of different angle filters and prism films in a photosensitive element in an optical fingerprint recognition system according to an embodiment of the present invention.

FIG. 6A and FIG. 6B are respectively schematic diagrams of photosensitive elements using different placement modes in an optical fingerprint identification system according to an embodiment of the present invention.

FIG. 7 is a schematic diagram of an optical fingerprint identification system and a display panel according to an embodiment of the present invention.

FIG. 8 is a schematic diagram of a combination of an optical fingerprint identification system and a camera lens of a mobile phone according to an embodiment of the present invention.

DESCRIPTION OF REFERENCE NUMERALS: 10-optical fingerprint identification system; 11-photosensitive element; 12-platen; 121-plate surface; 13-light diffusing plate; 131-through hole; 14-light source; 20-optical fingerprint identification system; Light guide panel; 211-fingerprint sensing area; 212-light-in end; 213-light-emitting end; 214-first light guiding part; 215-second light guiding part; 216-optical glue; 22-collimated light source; - parabolic concentrator or CPC; 222 - non-collimated light source; 223 - Fresnel lens; 224 - lens; 225 - prism; 23 - signal amplifier; 24 - photosensitive element; 251 - lens; 252 - prism film; Filter; 254 - first material film; 255 - second material film; 30 - display panel; 40 - lens module; 41 - polarizing beam splitting prism or beam splitter; A - finger; Θ - incident angle; A - tilt angle.

Detailed ways

Referring to FIG. 2, a cross-sectional view of an optical fingerprint recognition system 20 provided by an embodiment of the present invention is shown. The optical fingerprint recognition system 20 is mainly composed of a light guide panel 21, a collimated light source 22, a signal amplifier 23, and a light receiving element 24.

In this embodiment, the surface of the light guide panel 21 has a fingerprint sensing area 211 that can be pressed by the finger A. In practical applications, the fingerprint sensing area 211 can be designed on all or a partial area of the surface of the light guide panel 21. In this embodiment, the light guide panel 21 has an optical entrance end 212 and a light exit end 213 on both sides, and a first light guide portion 214 and a second light guide portion 215 are respectively disposed at the light entrance end 212 and the light exit end 213. Specifically, the first light guiding portion 214 and the second light guiding portion 215 can be reflectors for adjusting the transmission angle of the optical signal. In practical applications, the positions of the light incident end 212 and the light exiting end 213 can also be designed. The intermediate slit end of the light panel 21. The material of the light guide panel 21 may be glass. The first light guiding portion 214 and the second light guiding portion 215 may be in the form of a mirror or an optical fiber, and the first light guiding portion 214 and the second light guiding portion 215 are opposite to the light guiding portion. The panel 21 may be separately provided. Of course, the first light guiding portion 214 and the second light guiding portion 215 may also be designed in an integrated structure with the light guiding panel 21 .

In this embodiment, the collimated light source 22 is adjacent to the first light guiding portion 214 for providing at least one optical signal for collimation. Further, the collimated light source 22 generates a collimated optical signal, and directs the optical signal to the first light guiding portion 214. The first light guiding portion 214 reflects or transmits the optical signal, and is guided through the light incident end 212. In the light panel 21, the optical signal can be transmitted in the light guide panel 21 by the Total Internal Reflection (TIR) effect, and then transmitted to the light exit end 213, and then reflected or transmitted through the second light guide portion 215.

Furthermore, in order to allow the optical signal to be totally totally internally reflected in the light guiding panel 21, the angle between the optical signal and the normal of the surface or the bottom surface of the light guiding panel 21 (herein referred to as the following description, referred to as The incident angle θ), whose minimum angle is arcsin(n ₀ /n ₂ ) and arcsin(n ₁ /n ₂ ), respectively, can achieve total total reflection. Therefore, when the optical signal travels in the light guide panel 21, the incident angle θ needs to be greater than the minimum angle required for the total internal reflection, that is, the incident angle θ needs to be greater than arcsin(n ₀ /n ₂ ) and Arcsin(n ₁ /n ₂ );

Where n ₀ is the refractive index of the surface of the light guide panel 21;

n ₁ is the refractive index of the bottom surface of the light guide panel 21;

n ₂ is the refractive index of the light guide panel 21.

In this embodiment, the refractive index of the light guide panel 21 is 1.5. When the surface and the bottom surface of the light guide panel 21 are both adjacent to the air, the angle between the traveling direction of the optical signal in the light guide panel 21 and the surface or the bottom surface thereof is That is, the incident angle θ is greater than 43 degrees; when only one of the surface and the bottom surface of the light guide panel 21 is adjacent to the air and the other surface is adjacent to the material having a refractive index of 1.4, the optical signal travels in the light guide panel 21 The angle between the direction and its surface or bottom surface, that is, the incident angle θ is greater than 70 degrees.

In this embodiment, the collimated light source 22 can be a combination of a laser, a vertical cavity laser (VCSEL) or a non-collimated light source and a secondary optical element; specifically, the secondary optical component is optional. Parabolic surface concentrating mirrors, compound parabolic concentrating mirrors (CPC), lenses, prisms, Fresnel lenses, and combinations thereof. As shown in FIG. 3A, the embodiment of the present invention uses a parabolic concentrator or CPC221 to cooperate with the non-collimated light source 222 to provide a collimated optical signal; as shown in FIG. 3B, the embodiment of the present invention uses Fresnel. The lens 223 is coupled with the non-collimated light source 222 to provide a collimated optical signal; as shown in FIG. 3C, the embodiment of the present invention uses one (or more) lens 224 to be used in conjunction with the non-collimated light source 222 to provide a standard Straight optical signal. As shown in FIG. 3D, the embodiment of the present invention uses one (or more) prisms 225 to cooperate with the non-collimated light source 222 to provide a collimated optical signal through the prism 225; in the present invention, the prism 225 It may be disposed only between the first light guiding portion 214 and the collimated light source 22 or the non-collimated light source 222, or between the second light guiding portion 215 and the signal amplifier 23, or even in both places. The prism 225 can be a fixed or rotatable prism.

In addition, the optical signal may have a wavelength of 380 to 1400 nanometers (nm); in practical applications, it can be divided into a visible light segment (380 to 780 nm) and a near infrared segment (780 to 1400 nm). Further, when the wavelength of the visible light segment is used, it is visible to the naked eye, and different wavelengths can be used to indicate the effective or ineffective region to assist the user to understand the available region; when the wavelength of the near-infrared segment is used, it is invisible to the naked eye, and is suitable for use. Under the display panel (underdisplay) or in an environment where the demand is not perceived by the user. In addition, a coating film (not shown) is formed on the surface of the light guiding panel 21 for visible light to pass through, and the remaining wavelengths of light are reflected in the light guiding panel 21.

In this embodiment, the signal amplifier 23 is adjacent to the second light guiding portion 215 for receiving the optical signal derived by the second light guiding portion 215 and amplifying the optical signal, and the signal amplifier 23 may be in the form of a mirror.

In this embodiment, the photosensitive element 24 is adjacent to the signal amplifier 23 for receiving the optical signal derived by the signal amplifier 23 and processing the optical signal into a fingerprint image, thereby achieving the purpose of fingerprint recognition. When the user presses the fingerprint sensing area 211 on the surface of the light guiding panel 21 with the finger A, the optical signal is destroyed by the total reflection in the light guiding panel 21, and the photosensitive element 24 can detect the waveform change of the optical signal, and Processed as a fingerprint image to achieve the purpose of fingerprint recognition.

In this embodiment, the photosensitive element 24 and the signal amplifier 23 may further include a lens, a prism film, an angular filter, or a combination thereof. Referring to FIG. 4A to FIG. 4D, the lens 251, the prism film 252, the angle filter 253, and the prism film 252 and the angle filter 253 are combined on the photosensitive element 24 in the embodiment of the present invention.

The angle filter 253 shown in FIG. 4C is a vertical type grating filter. As shown in FIG. 5A, the angle filter 253 can also be a tilt type grating filter, and as shown in FIG. 4C and FIG. 5A, The angle filter 253 is a single layer structure formed by a plurality of layers of the first material film 254 spaced apart, or the angle filter 253 may be formed by a plurality of layers of the first material film 254 and the plurality of second material films 255. Single layer structure. In addition, as shown in FIG. 5B, the angle filter 253 may be a multilayer structure composed of a plurality of layers of the first material film 254 and the plurality of second material films 255, and the first of the different layers in the multilayer structure. The material film 254 is aligned, or, as shown in Figure 5C, the first material films 254 of the different layers in the multilayer structure are staggered. Further, as shown in FIGS. 5D to 5F, an embodiment in which the combination of the angle filter 253 and the prism film 252 in FIGS. 5A to 5C is combined with the photosensitive element 24 is shown.

The above embodiment provides internal total reflection in the light guide panel 21 by providing a collimated optical signal. In practical applications, the uncollimated light source 222 can also be used to provide an uncollimated optical signal in the light guide panel 21. The high-order angle filter 253 is further disposed on the photosensitive element 24 side, and the purpose of fingerprint imaging can also be achieved.

In addition, as shown in FIG. 6A, the photosensitive element 24 of the optical fingerprint recognition system 20 of the embodiment of the present invention can be placed in parallel with respect to the light guide panel 21; as shown in FIG. 6B, the optical provided by the embodiment of the present invention The photosensitive element 24 in the fingerprint recognition system 20 may also be inclined with respect to the light guide panel 21, and the inclination angle α may be, for example, 10 degrees, 45 degrees, or 90 degrees.

The present invention is applied to a product in which the optical fingerprint identification system 20 is integrated with the display panel. As shown in FIG. 7 , in the embodiment, the light guide panel 21 is disposed above a display panel 30 , and the photosensitive element 24 is concealed in the display panel 30 . On the back side of the light guide panel 21, the light guide panel 21 is attached to the display panel 30 by a coating optical adhesive 216 or a dispensing method. In order to easily achieve full surface fingerprint recognition, the light guide panel 21 is preferably used. It is a method of coating the optical glue on the entire bottom surface. Since the photosensitive element 24 of the present invention is not detected by the reflected light of the received fingerprint, it does not cause a problem of insufficient penetration, which makes the application more extensive.

In addition, the present invention can also combine the optical fingerprint recognition system 20 with the camera lens of the mobile phone. As shown in FIG. 8, in this embodiment, a polarization splitting prism (PBS) or splitting is disposed between the photosensitive element 24 and the signal amplifier 23. The mirror (BS) 41, on the one hand, can provide the optical signal derived from the signal amplifier 23 to the photosensitive element 24 for sensing imaging, and on the other hand, can provide the optical signal transmitted by the lens module 40 to the photosensitive element 24 for sensing imaging. That is to say, the present invention can be shared with the camera lens of the mobile phone to reach the photosensitive element 24, so that the optical fingerprint recognition system 20 does not occupy too much structural space, so that the volume of the final product can be simplified.

In the above embodiment, the type, shape, number, and relative of the light guide panel 21 and its first light guiding portion 214 and second light guiding portion 215, the collimated light source 22 or the non-collimated light source 222, the signal amplifier 23, and the photosensitive element 24 are opposite. The positional relationship is only an example, and is not limited thereto, and any one of the spirits of the present invention does not depart from the scope of the present invention.

In summary, the optical fingerprint identification system according to the present invention provides a collimated optical signal through a light guide panel as a fingerprint sensing area for finger pressing, and is designed with a first light guiding portion and a second light guiding portion. The optical signal is capable of transmitting the total total reflection effect in the light guide panel, and then amplified by the signal, and finally the photosensitive element detects the waveform change thereof to obtain the fingerprint image. Compared with the existing optical fingerprint identification system, the photosensitive element is detected by receiving the light reflected by the finger, and there is a problem of the penetration above the photosensitive element, so that the configuration of the fingerprint identification related component has its limitation; The optical fingerprint identification system provided by the invention is relatively easy to configure, in particular, when the optical fingerprint identification system is integrated with the display panel, the photosensitive element can be concealed on the back side of the display panel without affecting the lack of penetration and affecting the recognition rate. Conducive to the design of the product to meet the consumer's aesthetic needs for the appearance of the product. The invention can also integrate the optical fingerprint identification system with the lens module. By adding a polarization splitting prism (PBS) or a beam splitter (BS), the photosensitive element can be shared, and the product structure can be simplified. Further, a regional or comprehensive fingerprint sensing area can be designed to allow the user to use the fingerprint recognition function more flexibly and conveniently.

The above is only the preferred embodiment of the present invention and is not intended to limit the scope of the present invention. All changes or modifications of the features and spirits of the inventions are intended to be included within the scope of the invention.

Claims

An optical fingerprint identification system, comprising:

a light guide panel having a fingerprint sensing area for pressing by a finger, and the light guiding panel is respectively provided with a first light guiding portion and a second light guiding portion at an light incident end and a light exit end;

a light source adjacent to the first light guiding portion and providing at least one optical signal, the optical signal is introduced into the light guiding panel via the first light guiding portion, and transmitted through the total total reflection effect in the light guiding panel, and then Exporting the second light guiding portion;

a signal amplifier adjacent to the second light guiding portion, receiving the optical signal derived by the second light guiding portion, and amplifying the optical signal and then deriving; and

A photosensitive element, adjacent to the signal amplifier, receives the optical signal derived by the signal amplifier and processes the optical signal into a fingerprint image.
The optical fingerprint recognition system according to claim 1, wherein the fingerprint sensing area is all or a partial area of the surface of the light guiding panel.
The optical fingerprint identification system of claim 1 , wherein the light guide panel is disposed above a display panel.
The optical fingerprint identification system of claim 3, wherein the light guide panel is attached to the display panel by applying an optical glue or a dispensing method.
The optical fingerprint recognition system of claim 1 wherein the light source is a collimated source or a non-collimated source.
The optical fingerprint recognition system according to claim 5, wherein the collimated light source is a laser, a vertical cavity surface laser or a combination of a non-collimated light source and a secondary optical element.
The optical fingerprinting system of claim 6 wherein the secondary optical component is selected from the group consisting of a parabolic concentrating mirror, a compound parabolic concentrating mirror, a lens, a prism, a Fresnel lens, and combinations thereof.
The optical fingerprinting system of claim 1 wherein the optical signal has a wavelength between 380 and 1400 nanometers.
The optical fingerprint recognition system of claim 1 , wherein the optical signal is sandwiched between the optical signal and a normal of the surface or a bottom surface of the light guide panel when the optical signal travels within the light guide panel The angle needs to satisfy greater than arcsin(n 0 /n 2 ) and arcsin(n 1 /n 2 );

Where n 0 is the refractive index of the surface of the light guiding panel;

n 1 is the refractive index of the bottom surface of the light guiding panel; and

n 2 is the refractive index of the light guiding panel.
The optical fingerprint identification system according to claim 1, wherein the first light guiding portion, the second light guiding portion and the light guiding panel are integrated.
The optical fingerprint recognition system according to claim 1, wherein the first light guiding portion and the second light guiding portion are disposed separately from the light guiding panel.
The optical fingerprint identification system of claim 1 , wherein the surface of the light guiding panel forms a coating film for a visible light to pass through, and the remaining wavelengths of light are reflected.
The optical fingerprint recognition system according to claim 1, wherein the first light guiding portion and the second light guiding portion are in the form of a mirror or an optical fiber.
The optical fingerprinting system of claim 1 wherein the signal amplifier is in the form of a mirror.
The optical fingerprint identification system of claim 1 , further comprising a lens, a prism film, an angle filter, a polarization beam splitting prism, a beam splitter or a combination thereof between the light sensor and the signal amplifier.
The optical fingerprint recognition system according to claim 15, wherein the angle filter is a vertical type or a tilt type grating filter.
The optical fingerprint recognition system according to claim 16, wherein the grating filter is a single layer structure formed by a plurality of layers of the first material film being spaced apart.
The optical fingerprint recognition system according to claim 16, wherein the grating filter is a single layer structure formed by a plurality of layers of the first material film and the plurality of second material films.
The optical fingerprint identification system according to claim 16, wherein the grating filter is a multi-layer structure composed of a plurality of layers of the first material film and the plurality of second material films, and the multi-layer structure The first material films of the different layers are aligned or staggered.
The optical fingerprint recognition system of claim 1 wherein the photosensitive element is placed parallel or obliquely relative to the light guide panel.
The optical fingerprint identification system of claim 1 , wherein the first light guiding portion and the light source and/or the second light guiding portion and the signal amplifier further comprise at least one prism, and the The prism is a fixed or rotatable prism.