CN113505749A - Fingerprint identification module, fingerprint identification method and display device - Google Patents

Abstract

The disclosure provides a fingerprint identification module, a fingerprint identification method and a display device. Fingerprint identification module includes: a substrate base plate; the light converging layer is arranged on the substrate and is configured to carry out total reflection convergence on the stray reflection light reflected by the fingerprint; the photosensitive layer is arranged between the substrate and the light converging layer and is configured to receive the stray reflection light converged by the light converging layer and the main reflection light reflected by the fingerprint so as to generate a fingerprint signal. The fingerprint identification module, the fingerprint identification method and the display device can improve the accuracy of fingerprint identification.

Description

Fingerprint identification module, fingerprint identification method and display device

Technical Field

The disclosure relates to the technical field of display, in particular to a fingerprint identification module, a fingerprint identification method and a display device.

Background

With the continuous development of terminal technology, electronic devices are more and more widely applied. Due to the uniqueness of skin texture, such as fingerprint pattern or palm print pattern, in order to protect the information security of users, the use of fingerprint identification function on electronic devices is becoming more and more popular, such as for unlocking mobile phones, mobile payment (e.g. payment, money transfer), and the like.

In the related art, light emitted by a display device is totally reflected at fingerprint valley positions on an interface formed by the display device and a finger, the reflectivity of the fingerprint ridge positions is low, and the reflected light is collected by a photosensitive sensing unit to generate a fingerprint pattern.

At present, the light reflected by the fingerprint valley includes main reflected light and stray reflected light, and the reflection range of the stray reflected light is large, so that the fingerprint identification accuracy is influenced.

Disclosure of Invention

In view of the above, an object of the present disclosure is to provide a fingerprint identification module, a fingerprint identification method and a display device.

Based on above-mentioned purpose, this disclosure provides a fingerprint identification module, includes:

a substrate base plate;

the light converging layer is arranged on the substrate and is configured to carry out total reflection convergence on the stray reflection light reflected by the fingerprint;

the photosensitive layer is arranged between the substrate and the light converging layer and is configured to receive the stray reflection light converged by the light converging layer and the main reflection light reflected by the fingerprint so as to generate a fingerprint signal.

Optionally, the light converging layer includes:

the first electrode layer is arranged on the photosensitive layer;

the first microstructure units are arranged on the first electrode layer;

the plurality of second microstructure units are arranged on the first electrode layer and are arranged at intervals with the first microstructure units, a slope surface is formed at the junction of the second microstructure units and the first microstructure units, and an acute angle is formed between the slope surface and the first electrode layer;

the second electrode layer is arranged on one side, away from the photosensitive layer, of the second microstructure unit;

wherein the first electrode layer and the second electrode layer are configured to: an electric field is formed between the first electrode layer and the second electrode layer, so that the refractive index of the second microstructure unit is increased to be larger than that of the first microstructure unit, and the stray reflection light incident to the slope surface is reflected to the photosensitive layer.

Optionally, the refractive index of the second microstructure unit is increased to 1.1 to 1.2 times of the refractive index of the first microstructure unit.

Optionally, an acute angle θ between the slope surface and the first electrode layer satisfies:

arcsin(n1/n2)≤θ＜90°

where n1 represents the refractive index of the first microstructure unit and n2 represents the refractive index of the second microstructure unit.

Optionally, the first microstructure unit is a bar-shaped structure with an inverted trapezoidal cross section, and the second microstructure unit is a bar-shaped structure with a regular trapezoidal cross section.

Optionally, the first microstructure unit is a block structure with an inverted trapezoid cross section, the second microstructure unit is a block structure with a regular trapezoid cross section, and the plurality of first microstructure units and the plurality of second microstructure units are arranged in an array at intervals.

Optionally, the method further includes:

and the flat layer is arranged on the first microstructure unit and the second microstructure unit and is integrally formed with the second microstructure unit.

Optionally, the first electrode layer includes a plurality of first electrode units, and an orthographic projection of the first electrode unit on the substrate coincides with an orthographic projection of the second microstructure unit on the substrate near the bottom surface of the photosensitive layer.

Optionally, the second electrode layer includes a planar electrode layer structure; or the second electrode layer comprises a plurality of second electrode units, and the orthographic projection of the second electrode units on the substrate is superposed with the orthographic projection of the first electrode units on the substrate.

Optionally, the method further includes:

the touch sensor is configured to collect pressure information of a fingerprint position, and generate an electric signal based on the pressure information to form an electric field between the first electrode layer and the second electrode layer.

The present disclosure also provides a display device, including the fingerprint identification module as in any one of the above.

Optionally, the display device further includes a display panel, the fingerprint identification module includes a light convergence layer, a photosensitive layer, a substrate base plate and a touch sensor, the light convergence layer, the photosensitive layer and the substrate base plate are sequentially stacked in a direction away from the display panel on a backlight surface of the display panel, and the touch sensor is disposed on a light-emitting surface of the display panel.

The present disclosure also provides a fingerprint identification method, which is applied to a fingerprint identification module, wherein the fingerprint identification module comprises a substrate, a photosensitive layer and a light convergence layer, which are sequentially stacked; the method comprises the following steps:

the stray reflection light reflected by the fingerprint is subjected to total reflection convergence through the light convergence layer;

and receiving the stray reflection light rays converged by the light converging layer and the main reflection light rays reflected by the fingerprint through the photosensitive layer to generate a fingerprint signal.

Optionally, the light converging layer includes a first electrode layer, a second electrode layer, and a plurality of first microstructure units and a plurality of second microstructure units disposed between the first electrode layer and the second electrode layer, and a slope is formed at a junction between the second microstructure units and the first microstructure units, and an acute angle is formed between the slope and the first electrode layer;

the total reflection convergence of the stray reflection light reflected by the fingerprint through the light convergence layer comprises:

an electric field is formed between the first electrode layer and the second electrode layer, so that the refractive index of the second microstructure unit is increased to be larger than that of the first microstructure unit, and the stray reflection light incident to the slope surface is reflected to the photosensitive layer.

Optionally, the fingerprint identification module further includes a touch sensor; the method further comprises the following steps:

collecting pressure information of a fingerprint position, and generating an electric signal based on the pressure information to form an electric field between the first electrode layer and the second electrode layer.

From the above can see, the fingerprint identification module and fingerprint identification method, display device that this disclosure provided, carry out total reflection convergence with the stray reflection light through the fingerprint reflection through the light convergence layer and transmit for the photosensitive layer, thereby make the photosensitive layer can receive and handle stray reflection light and the main reflection light through the fingerprint reflection after the light convergence layer converges, thereby generate fingerprint signal, not only avoided stray reflection light to fingerprint identification's interference, also can get up stray reflection light to utilize together to realize fingerprint identification simultaneously, thereby fingerprint identification's accuracy has been improved.

Drawings

In order to more clearly illustrate the technical solutions in the present disclosure or related technologies, the drawings needed to be used in the description of the embodiments or related technologies are briefly introduced below, and it is obvious that the drawings in the following description are only embodiments of the present disclosure, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic diagram illustrating a fingerprint recognition principle according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of a fingerprint identification module according to an embodiment of the disclosure;

FIG. 3 is a schematic diagram illustrating a principle of total reflection of the stray reflected light according to the embodiment of the present disclosure;

fig. 4 is another schematic structural diagram of the fingerprint identification module according to the embodiment of the disclosure;

fig. 5 is a schematic structural diagram of a display device according to an embodiment of the disclosure;

FIG. 6 is a schematic flowchart illustrating a fingerprint identification method according to an embodiment of the disclosure;

fig. 7 is another schematic flow chart of a fingerprint identification method according to an embodiment of the disclosure.

Detailed Description

For the purpose of promoting a better understanding of the objects, aspects and advantages of the present disclosure, reference is made to the following detailed description taken in conjunction with the accompanying drawings.

It is to be noted that technical terms or scientific terms used in the embodiments of the present disclosure should have a general meaning as understood by those having ordinary skill in the art to which the present disclosure belongs, unless otherwise defined. The use of "first," "second," and similar terms in the embodiments of the disclosure is not intended to indicate any order, quantity, or importance, but rather to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

The technology for identifying fingerprints under the screen is characterized in that a fingerprint sensor is integrated below a display panel, and light leakage areas are formed at certain intervals among pixels of the display panel, so that light can be ensured to penetrate through the display panel. As shown in fig. 1, when a user touches and presses the screen with a finger, the screen emits light to illuminate the finger area, and the reflected light illuminating the fingerprint returns to the image sensor closely attached to the lower side of the display panel through the gaps of the pixels of the screen.

The finger fingerprint includes a fingerprint ridge area and a fingerprint valley area. Since the fingerprint tissue in the fingerprint ridge area absorbs light, the light reflected from the fingerprint ridge becomes dark; the light reflected from the fingerprint valleys is relatively bright. Therefore, the brightness difference generated by the fingerprint ridge and the fingerprint valley can form a fingerprint pattern on the image sensor, and the image sensor arranged below the display device realizes the identification of the fingerprint under the screen by detecting the reflected light carrying the fingerprint information of the user.

In the fingerprint identification process, because the reflected light of fingerprint valley includes main reflection light and spurious reflection light, and spurious reflection light can cause the interference to fingerprint identification, if do not handle spurious reflection light, then can influence fingerprint identification's accuracy.

Based on above-mentioned reason, this disclosure provides a fingerprint identification module, can get together stray reflection light and be used for fingerprint identification to improve fingerprint identification's accuracy.

As shown in fig. 2, the fingerprint identification module according to the embodiment of the disclosure includes a substrate 1, a light converging layer 3, and a photosensitive layer 2.

The light converging layer 2 is disposed on the substrate 1, and is configured to transmit the stray reflected light reflected by the fingerprint to the photosensitive layer 2 after being converged by total reflection. The photosensitive layer 2 is disposed between the substrate 1 and the light converging layer 3, and the photosensitive layer 2 is configured to receive the stray reflected light converged by the light converging layer 2 and the main reflected light reflected by the fingerprint to generate a fingerprint signal.

The utility model discloses embodiment fingerprint identification module, carry out the total reflection through light convergence layer 2 and converge the after-transmission for photosensitive layer 2 with the stray reflection light of passing through the fingerprint reflection, thereby make photosensitive layer 2 can receive and handle stray reflection light and the main reflection light of passing through the fingerprint reflection after light convergence layer 2 converges, thereby generate fingerprint signal, stray reflection light has not only been avoided to fingerprint identification's interference, also can utilize stray reflection light together to realize fingerprint identification simultaneously, thereby fingerprint identification's accuracy has been improved.

Optionally, the main reflected light and the stray reflected light in this embodiment may be both reflected light from the fingerprint valley.

Alternatively, the substrate board 1 may be a glass plate, a quartz plate, a metal plate, a resin plate, or the like. For example, the material of the substrate 1 may include an organic material, for example, the organic material may be a resin material such as Polyimide (PI), polycarbonate, polyacrylate, polyetherimide, polyethersulfone, polyethylene terephthalate, and polyethylene naphthalate, and the substrate 1 may be a flexible substrate or a non-flexible substrate, which is not limited in this respect by the embodiment of the present disclosure.

Alternatively, the photosensitive layer 2 may include an image sensor or a fingerprint sensor. Wherein, when photosensitive layer 2 includes image sensor, image sensor includes the sensitization unit array that a plurality of arrays set up, and sensitization unit array can receive main reflection light through fingerprint reflection and the stray reflection light after gathering by light convergence layer 2 to based on main reflection light and the corresponding signal of telecommunication of stray reflection light generation, and finally generate fingerprint signal, this fingerprint signal can be used to information such as generation fingerprint image. When the photosensitive layer 2 includes a fingerprint sensor, the fingerprint sensor may be composed of a photodiode array and a transistor, wherein the photodiode array may absorb a main reflected light reflected by a fingerprint and a stray reflected light converged by the light converging layer 2, and the transistor may convert the light received by the photodiode array into an electrical signal corresponding to the light intensity for output, so as to generate a fingerprint signal.

In some embodiments of the present disclosure, as shown in fig. 2, the light converging layer 3 includes a first electrode layer 31, a second electrode layer 32, and a plurality of first microstructure units 33 and a plurality of second microstructure units 34 disposed between the first electrode layer 31 and the second electrode layer 32.

As shown in fig. 2, in the present embodiment, the first electrode layer 31 is disposed on the photosensitive layer 2. The first microstructure units 33 and the second microstructure units 34 are disposed on the first electrode layer 31 and far away from the substrate base plate 1. The second microstructure units 34 and the first microstructure units 33 are arranged at intervals, and a slope surface is formed at the boundary between the second microstructure units 34 and the first microstructure units 33, and an acute angle is formed between the slope surface and the first electrode layer 31; the second electrode layer 32 is disposed on a side of the second microstructure unit 34 away from the photosensitive layer.

Wherein the first electrode layer 31 and the second electrode layer 32 are configured to: an electric field is formed between the first electrode layer 31 and the second electrode layer 32, so that the refractive index of the second microstructure unit 34 is increased to be greater than that of the first microstructure unit 33, and the stray reflection light incident on the slope surface is reflected to the photosensitive layer 2.

In this embodiment, when no electric field is formed between the first electrode layer 31 and the second electrode layer 32, the refractive index of the first microstructure unit 33 is substantially the same as the refractive index of the second microstructure unit 34, for example, the refractive index of the first microstructure unit 33 is only different from the refractive index of the second microstructure unit 34 by 0-0.002, so that there is almost no total reflection when light is transmitted between the first microstructure unit 33 and the second microstructure unit 34, and thus, when the display device is displaying normally, the display image will not be uneven in bright and dark display due to the total reflection of light between the first microstructure unit 33 and the second microstructure unit 34.

When fingerprint identification is needed, an electric field is formed between the first electrode layer 31 and the second electrode layer 32, at this time, under the action of the electric field, the refractive index of the second microstructure unit 34 is increased until the refractive index of the second microstructure unit 34 is greater than that of the first microstructure unit 33, so that stray reflection light incident to a slope surface from the second microstructure unit 34 can be totally reflected, and the totally reflected stray reflection light can be absorbed by the photosensitive layer 2 after being transmitted to the photosensitive layer 2, thereby improving the accuracy of fingerprint identification.

Optionally, the joints of two adjacent slope surfaces and the first electrode layer 31 are not overlapped and have a certain distance, so as to ensure that the stray reflected light after being totally reflected by the slope surfaces can be transmitted to the photosensitive layer 2.

In some optional embodiments, when an electric field is formed between the first electrode layer 31 and the second electrode layer 32, the magnitude of the electric field needs to be controlled so that the refractive index of the second microstructure unit 34 is increased to be 1.1 to 1.2 times of the refractive index of the first microstructure unit 33, so as to ensure that the stray reflection light can be not only totally reflected when being incident to the slope surface, but also can enter the photosensitive layer 2 after being totally reflected so as to be absorbed by the photosensitive layer 2.

In some alternative embodiments, as shown in fig. 3, the acute angle θ between the slope surface and the first electrode layer 31 satisfies:

arcsin(n1/n2)≤θ＜90°

where n1 represents the refractive index of the first microstructure unit 33 when no electric field is applied, n2 represents the refractive index of the second microstructure unit 34 when no electric field is applied, and arcsin (x) represents the angle in degrees.

Optionally, when the acute angle θ between the slope surface and the first electrode layer 31 is in the range of 60 ° to 80 °, the light converging layer 3 can achieve a better reflection effect on the stray reflected light.

In some embodiments, as shown in fig. 2, the first microstructure unit 33 is a bar-shaped structure with an inverted trapezoid cross section, and the second microstructure unit 34 is a bar-shaped structure with a regular trapezoid cross section, which are spaced apart from each other.

In other embodiments, the first microstructure unit 33 is a block structure with an inverted trapezoid cross section, the second microstructure unit 34 is a block structure with a regular trapezoid cross section, and the plurality of first microstructure units 33 and the plurality of second microstructure units 34 are arranged in an array at intervals, so that the number of slope surfaces between the first microstructure units 33 and the second microstructure units 34 is increased, the reflection effect on stray reflection light is improved, and the accuracy of fingerprint identification is further improved.

In some embodiments, as shown in FIG. 4, the fingerprint recognition module further comprises a flat layer 35. The planarization layer 35 is disposed on the first microstructure unit 33 and the second microstructure unit 34, and is integrally formed with the second microstructure unit 34. The formation of the second electrode layer 32 and other structures is facilitated by providing the planarization layer 35 to planarize the sides of the first and second microstructure units 33 and 34 facing the second electrode layer 32.

Optionally, after the first microstructure units 33 with the inverted trapezoid cross section are formed on the first electrode layer 31, the material of the second microstructure units 34 is used to fill the gaps between the first microstructure units 33, and the second microstructure units 34 and the structure of the planarization layer 35 are formed at the same time.

In some embodiments, the first electrode layer 31 includes a plurality of first electrode units, and an orthographic projection of the first electrode units on the substrate base plate 1 coincides with an orthographic projection of the second microstructure units 34 on the substrate base plate 1 near the bottom surface of the photosensitive layer, so that an electric field formed between the first electrode layer 31 and the second electrode layer 32 can be applied to only the second microstructure units 34, and thus only the refractive index of the second microstructure units 34 is increased to be greater than that of the first microstructure units 33, thereby realizing total reflection of the stray reflected light.

Optionally, as shown in fig. 4, the second electrode layer 32 includes a planar electrode layer structure, so as to facilitate manufacturing and forming of the second electrode layer 32. Or, the second electrode layer 32 includes a plurality of second electrode units, and an orthographic projection of the second electrode units on the substrate base plate 1 coincides with an orthographic projection of the first electrode units on the substrate base plate 1, so that an electric field can be applied only to the second microstructure units 34, and only the refractive index of the second microstructure units 34 is increased to be greater than that of the first microstructure units 33, thereby realizing total reflection of stray reflected light.

In other embodiments of the present disclosure, the fingerprint identification module further includes a touch sensor. The touch sensor is configured to collect pressure information of a fingerprint position and generate an electric signal based on the pressure information to form an electric field between the first electrode layer 31 and the second electrode layer 32. In this embodiment, when a finger touches the fingerprint recognition location, pressure is formed on the display device; when detecting the pressure signal corresponding to the fingerprint identification, the touch sensor may convert the pressure signal into an electrical signal, the electrical signal may be processed to form an electric field signal applied between the first electrode layer 31 and the second electrode layer 32, and an electric field may be formed between the first electrode layer 31 and the second electrode layer 32 based on the electric field signal, so that the refractive index of the second microstructure unit 34 may be increased to be greater than the refractive index of the first microstructure unit 33, thereby implementing total reflection of the stray reflected light.

Optionally, the touch sensor may be disposed on a light emitting surface of the display panel, or may be disposed on a backlight surface of the display panel.

Based on the same inventive concept, the embodiment of the present disclosure further provides a display device, which includes the fingerprint identification module according to any of the above embodiments.

As shown in fig. 5, the display device further includes a display panel 4. The display panel 4 may include a liquid crystal display panel, an OLED display panel, and the like, which is not limited in this respect by the embodiments of the present disclosure.

The fingerprint identification module comprises a light convergence layer 3, a photosensitive layer 2, a substrate base plate 1 and a touch sensor 5. The light converging layer 3, the photosensitive layer 2 and the substrate base plate 1 are sequentially stacked on a backlight surface of the display panel 4 along a direction away from the display panel 4, and the touch sensor 5 is arranged on a light emitting surface of the display panel 4.

Optionally, the display device may further include a polarizer, a cover plate, and other structures disposed on the display panel 4.

The display device of the above embodiment includes the fingerprint identification module described in any of the foregoing embodiments, and has the beneficial effects of the corresponding fingerprint identification module embodiment, which are not described herein again.

The display device in this embodiment may be: any product or component with a display function, such as electronic paper, a mobile phone, a tablet computer, a television, a notebook computer, a digital photo frame, a navigator and the like.

It is noted that in the drawings, the sizes of layers and regions may be exaggerated for clarity of illustration. Also, it will be understood that when an element or layer is referred to as being "on" another element or layer, it can be directly on the other element or layer or intervening layers may also be present. In addition, it will be understood that when an element or layer is referred to as being "under" another element or layer, it can be directly under the other element or intervening layers or elements may also be present. In addition, it will also be understood that when a layer or element is referred to as being "between" two layers or elements, it can be the only layer between the two layers or elements, or there can be more than one intermediate layer or element. Like reference numerals refer to like elements throughout.

Based on the same inventive concept, the embodiment of the disclosure also provides a fingerprint identification method. The fingerprint identification method is applied to a fingerprint identification module, wherein, as shown in fig. 2 and 4, the fingerprint identification module comprises a substrate base plate 1, a photosensitive layer 2 and a light convergence layer 3 which are sequentially stacked. As shown in fig. 6, the fingerprint identification method includes:

step S101, the stray reflection light reflected by the fingerprint is subjected to total reflection convergence through the light convergence layer.

Step S102, receiving the stray reflection light converged by the light converging layer and the main reflection light reflected by the fingerprint through the photosensitive layer to generate a fingerprint signal.

In some optional embodiments, as shown in fig. 2 and 4, the light converging layer 3 includes a first electrode layer 31, a second electrode layer 32, and a plurality of first microstructure units 33 and a plurality of second microstructure units 34 disposed between the first electrode layer 31 and the second electrode layer 32, and a slope is formed at a boundary between the second microstructure units 34 and the first microstructure units 31, and an acute angle is formed between the slope and the first electrode layer 31. In step S101, the total reflection converging of the stray reflected light reflected by the fingerprint by the light converging layer includes: an electric field is formed between the first electrode layer and the second electrode layer, so that the refractive index of the second microstructure unit is increased to be larger than that of the first microstructure unit, and the stray reflection light incident to the slope surface is reflected to the photosensitive layer.

Optionally, the fingerprint identification module further includes a touch sensor; the method further comprises the following steps: collecting pressure information of a fingerprint position, and generating an electric signal based on the pressure information to form an electric field between the first electrode layer and the second electrode layer. In this embodiment, the pressure information of the fingerprint position may be collected by a touch sensor, and an electrical signal for forming an electric field between the first electrode layer and the second electrode layer may be generated based on the pressure information.

In some optional embodiments, as shown in fig. 7, the fingerprint identification method further includes:

step S201, collecting pressure information of a fingerprint position, and generating an electric signal based on the pressure information.

In this step, when it is detected that the finger touches the fingerprint identification position, the pressure information of the fingerprint position is collected by the touch sensor 5, and an electrical signal is generated based on the pressure information, and the electrical signal may be processed to form an electric field signal applied between the first electrode layer 31 and the second electrode layer 32.

Meanwhile, only when it is detected that the finger touches the fingerprint recognition position, the touch sensor 5 generates an electric signal for applying an electric field between the first electrode layer 31 and the second electrode layer 32. When the finger touch fingerprint identification position is not detected, no electric signal is generated and no electric field is applied between the first electrode layer 31 and the second electrode layer 32, so that the brightness and darkness of the picture are not uniform due to the total reflection of the light between the first microstructure unit 33 and the second microstructure unit 34.

Step S202, applying the electric signal between the first electrode layer and the second electrode layer, thereby forming an electric field between the first electrode layer and the second electrode layer.

In this embodiment, since the refractive index of the second microstructure unit 34 needs to be increased to 1.1-1.2 times of the refractive index of the first microstructure unit 33 to achieve the total reflection of the stray reflection light when the stray reflection light is incident on the slope surface, the size of the electric field needs to be controlled to increase the refractive index of the second microstructure unit 34 to 1.1-1.2 times of the refractive index of the first microstructure unit 33, so as to ensure that the stray reflection light can be totally reflected when the stray reflection light is incident on the slope surface, and can also ensure that the stray reflection light can enter the photosensitive layer 2 after being totally reflected, so that the stray reflection light can be absorbed by the photosensitive layer 2.

Step S203 is to form a certain electric field between the first electrode layer and the second electrode layer, and then the refractive index of the second microstructure unit at the electric field area is increased, so that the stray reflection light incident on the slope surface via the second microstructure unit can be totally reflected to the photosensitive layer.

In this embodiment, the orthographic projections of the plurality of first electrode units included in the first electrode layer 31 on the substrate 1 coincide with the orthographic projections of the second microstructure units 34 on the substrate 1 near the bottom surface of the photosensitive layer, so that the electric field formed between the first electrode layer 31 and the second electrode layer 32 can be applied to only the second microstructure units 34. The second electrode layer 32 may include a planar electrode layer structure. Alternatively, the second electrode layer 32 may include a plurality of second electrode units, and an orthogonal projection of the second electrode units on the substrate 1 coincides with an orthogonal projection of the first electrode units on the substrate 1, so that an electric field may be applied only to the second microstructure units 34.

Step S204, the photosensitive layer 2 collects the stray reflected light and the main reflected light reflected by the fingerprint after the light converging layer 2 converges, and generates a fingerprint signal, and finally a fingerprint image can be generated. Because the light convergence layer 2 can carry out total reflection convergence on stray light reflected by the fingerprint valley to the photosensitive layer 2, the interference of the stray reflected light on fingerprint identification is avoided, and the stray reflected light can be utilized to realize fingerprint identification together, so that the accuracy of fingerprint identification is improved.

Those of ordinary skill in the art will understand that: the discussion of any embodiment above is meant to be exemplary only, and is not intended to intimate that the scope of the disclosure, including the claims, is limited to these examples; within the idea of the present disclosure, also technical features in the above embodiments or in different embodiments may be combined, steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present disclosure as described above, which are not provided in detail for the sake of brevity.

In addition, well-known power/ground connections to Integrated Circuit (IC) chips and other components may or may not be shown in the provided figures for simplicity of illustration and discussion, and so as not to obscure the embodiments of the disclosure. Furthermore, devices may be shown in block diagram form in order to avoid obscuring embodiments of the present disclosure, and this also takes into account the fact that specifics with respect to implementation of such block diagram devices are highly dependent upon the platform within which the embodiments of the present disclosure are to be implemented (i.e., specifics should be well within purview of one skilled in the art). Where specific details (e.g., circuits) are set forth in order to describe example embodiments of the disclosure, it should be apparent to one skilled in the art that the embodiments of the disclosure can be practiced without, or with variation of, these specific details. Accordingly, the description is to be regarded as illustrative instead of restrictive.

While the present disclosure has been described in conjunction with specific embodiments thereof, many alternatives, modifications, and variations of these embodiments will be apparent to those of ordinary skill in the art in light of the foregoing description. For example, other memory architectures (e.g., dynamic ram (dram)) may use the discussed embodiments.

The disclosed embodiments are intended to embrace all such alternatives, modifications and variances which fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalents, improvements, and the like that may be made within the spirit and principles of the embodiments of the disclosure are intended to be included within the scope of the disclosure.

Claims (15)

1. A fingerprint identification module, comprising:

a substrate base plate;

the light converging layer is arranged on the substrate and is configured to carry out total reflection convergence on the stray reflection light reflected by the fingerprint;

the photosensitive layer is arranged between the substrate and the light converging layer and is configured to receive the stray reflection light converged by the light converging layer and the main reflection light reflected by the fingerprint so as to generate a fingerprint signal.

2. The fingerprint identification module of claim 1, wherein the light converging layer comprises:

the first electrode layer is arranged on the photosensitive layer;

the first microstructure units are arranged on the first electrode layer;

the plurality of second microstructure units are arranged on the first electrode layer and are arranged at intervals with the first microstructure units, a slope surface is formed at the junction of the second microstructure units and the first microstructure units, and an acute angle is formed between the slope surface and the first electrode layer;

the second electrode layer is arranged on one side, away from the photosensitive layer, of the second microstructure unit;

wherein the first electrode layer and the second electrode layer are configured to: an electric field is formed between the first electrode layer and the second electrode layer, so that the refractive index of the second microstructure unit is increased to be larger than that of the first microstructure unit, and the stray reflection light incident to the slope surface is reflected to the photosensitive layer.

3. The fingerprint identification module of claim 2, wherein the refractive index of the second microstructure unit is increased to 1.1-1.2 times the refractive index of the first microstructure unit.

4. The fingerprint identification module of claim 2, wherein an acute angle θ between the sloped surface and the first electrode layer satisfies:

arcsin(n1/n2)≤θ＜90°

where n1 represents the refractive index of the first microstructure unit and n2 represents the refractive index of the second microstructure unit.

5. The fingerprint identification module of claim 2, wherein the first microstructure unit is a bar structure with an inverted trapezoid cross section, and the second microstructure unit is a bar structure with a regular trapezoid cross section.

6. The fingerprint identification module of claim 2, wherein the first microstructure unit is a block structure with an inverted trapezoid cross section, the second microstructure unit is a block structure with a regular trapezoid cross section, and the plurality of first microstructure units and the plurality of second microstructure units are arranged in a spaced array.

7. The fingerprint identification module of claim 5 or 6, further comprising:

and the flat layer is arranged on the first microstructure unit and the second microstructure unit and is integrally formed with the second microstructure unit.

8. The fingerprint identification module of claim 5 or 6, wherein the first electrode layer comprises a plurality of first electrode units, and an orthographic projection of the first electrode units on the substrate coincides with an orthographic projection of the second microstructure units on the substrate near the bottom surface of the photosensitive layer.

9. The fingerprint identification module of claim 8, wherein the second electrode layer comprises a planar electrode layer structure; or the second electrode layer comprises a plurality of second electrode units, and the orthographic projection of the second electrode units on the substrate is superposed with the orthographic projection of the first electrode units on the substrate.

10. The fingerprint identification module of claim 2, further comprising:

the touch sensor is configured to collect pressure information of a fingerprint position, and generate an electric signal based on the pressure information to form an electric field between the first electrode layer and the second electrode layer.

11. A display device comprising the fingerprint identification module of any one of claims 1-10.

12. The display device according to claim 11, wherein the display device further comprises a display panel, the fingerprint identification module comprises a light converging layer, a photosensitive layer, a substrate and a touch sensor, the light converging layer, the photosensitive layer and the substrate are sequentially stacked on a backlight surface of the display panel along a direction away from the display panel, and the touch sensor is disposed on a light emitting surface of the display panel.

13. A fingerprint identification method is applied to a fingerprint identification module, and the fingerprint identification module comprises a substrate base plate, a photosensitive layer and a light convergence layer which are sequentially stacked; the method comprises the following steps:

the stray reflection light reflected by the fingerprint is subjected to total reflection convergence through the light convergence layer;

and receiving the stray reflection light rays converged by the light converging layer and the main reflection light rays reflected by the fingerprint through the photosensitive layer to generate a fingerprint signal.

14. The fingerprint identification method according to claim 13, wherein the light converging layer comprises a first electrode layer, a second electrode layer, and a plurality of first microstructure units and a plurality of second microstructure units arranged between the first electrode layer and the second electrode layer, and a slope is formed at a junction of the second microstructure units and the first microstructure units, and an acute angle is formed between the slope and the first electrode layer;

the total reflection convergence of the stray reflection light reflected by the fingerprint through the light convergence layer comprises:

an electric field is formed between the first electrode layer and the second electrode layer, so that the refractive index of the second microstructure unit is increased to be larger than that of the first microstructure unit, and the stray reflection light incident to the slope surface is reflected to the photosensitive layer.

15. The fingerprint identification method of claim 14, wherein the fingerprint identification module further comprises a touch sensor; the method further comprises the following steps:

collecting pressure information of a fingerprint position, and generating an electric signal based on the pressure information to form an electric field between the first electrode layer and the second electrode layer.

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