Texture recognition device and display device
A texture recognition device and a display device are provided. The texture recognition device includes a backlight element, configured to provide first backlight; a light constraint element, configured to perform a light divergence angle constraint process on the first backlight to obtain second backlight with a divergence angle within a preset angle range, the second backlight being transmitted to a detection object; and a photosensitive element, configured to detect the second backlight reflected by a texture of the detection object to recognize a texture image of the texture of the detection object.
1 . A texture recognition device, comprising:
a backlight element, configured to provide first backlight;
a light constraint element, configured to perform a light divergence angle constraint process on the first backlight to obtain second backlight with a divergence angle within a preset angle range, wherein the second backlight is transmitted to a detection object; and
a photosensitive element, configured to detect the second backlight reflected by a texture of the detection object to recognize a texture image of the texture of the detection object;
wherein the backlight element comprises an edge-lit backlight light source and a light guide plate, the light guide plate is on a light exit side of the edge-lit backlight light source,
the light guide plate comprises a first light incident surface, a first light reflecting surface, and a first light exit surface, and the first light reflecting surface and the first light exit surface are oppositely arranged in a first direction,
the first light reflecting surface comprises a prism pillar structure array, the prism pillar structure array comprises a plurality of triangular prism pillars arranged in sequence along a second direction.
2 . The texture recognition device according to claim 1 , wherein the light constraint element comprises a collimating film, the collimating film has a mesh structure and comprises a plurality of hollowed-out regions, and each of the plurality of hollowed-out regions is configured to transmit part first backlight, whose divergence angle is within the preset angle range, of the first backlight to obtain the second backlight.
3 . The texture recognition device according to claim 2 , wherein the plurality of hollowed-out regions are arranged in an array, and a shape of each of the plurality of hollowed-out regions comprises a square, a rectangle, a regular triangle, a regular hexagon, or a circle.
4 . The texture recognition device according to claim 3 , wherein a thickness of the collimating film ranges from 400 μm to 800 μm.
5 . The texture recognition device according to claim 3 , wherein a size of each of the plurality of hollowed-out regions ranges from 25 μm to 65 μm,
in a case where the shape of each of the plurality of hollowed-out regions is a square, a side length of the square ranges from 25 μm to 65 μm;
in a case where the shape of each of the plurality of hollowed-out regions is a rectangle, a long side of the rectangle ranges from 25 μm to 65 μm, a short side of the rectangle ranges from 25 μm to 65 μm, and a length of the long side is greater than a length of the short side;
in a case where the shape of each of the plurality of hollowed-out regions is a regular triangle, a side length of the regular triangle ranges from 25 μm to 65 μm;
in a case where the shape of each of the plurality of hollowed-out regions is a regular hexagon, a distance between two parallel sides of the regular hexagon ranges from 25 μm to 65 μm; and
in a case where the shape of each of the plurality of hollowed-out regions is a circle, a diameter of the circle ranges from 25 μm to 65 μm.
6 . The texture recognition device according to claim 2 , wherein the edge-lit backlight light source is configured to provide light source backlight, and the light source backlight is transmitted through the light guide plate to obtain initial backlight, and the first backlight comprises the initial backlight.
7 . The texture recognition device according to claim 2 , wherein the photosensitive element comprises a plurality of photosensitive sensors arranged in an array, and the plurality of photosensitive sensors are in one-to-one correspondence to the plurality of hollowed-out regions.
8 . The texture recognition device according to claim 7 , wherein each of the plurality of photosensitive sensors comprises a light transmitting region and a photoelectric conversion region.
9 . The texture recognition device according to claim 8 , wherein the light transmitting region at least partially surrounds the photoelectric conversion region.
10 . The texture recognition device according to claim 1 , wherein the light constraint element comprises an inverse prism sheet, the inverse prism sheet is on a light exit side of the light guide plate,
the edge-lit backlight light source is configured to provide light source backlight, and the light source backlight is transmitted through the light guide plate to obtain initial backlight, and the first backlight comprises the initial backlight; and
the inverse prism sheet is configured to cause the first backlight to be refracted to obtain the second backlight.
11 . The texture recognition device according to claim 10 , wherein the first light incident surface is configured to receive the light source backlight, the first light reflecting surface is configured to reflect the light source backlight, and the initial backlight emits from the first light exit surface,
the second direction is perpendicular to the first direction, a thickness of each of the plurality of triangular prism pillars is less than 2.5 μm in the first direction, a distance between two adjacent triangular prism pillars ranges from 45 μm to 50 μm in the second direction.
12 . The texture recognition device according to claim 10 , wherein the inverse prism sheet comprises a second light incident surface and a second light exit surface, the second light incident surface and the second light exit surface are oppositely arranged in the first direction, the second light incident surface is configured to receive the first backlight, the second backlight emits from the second light exit surface,
the second light incident surface comprises a prism structure array, the prism structure array comprises a plurality of inverse prisms arranged in sequence along the second direction,
in the first direction, a thickness of each of the plurality of inverse prisms ranges from 10 μm to 25 μm, and in the second direction, a distance between two adjacent inverse prisms of the plurality of inverse prisms ranges from 20 μm to 50 μm.
13 . The texture recognition device according to claim 12 , wherein the second light incident surface comprises a first side surface and a second side surface of each of the plurality of inverse prisms.
14 . The texture recognition device according to claim 10 , wherein the photosensitive element comprises a plurality of photosensitive sensors, the plurality of photosensitive sensors constitute a photosensitive sensor array, and
in the first direction, the inverse prism sheet is located between the light guide plate and the photosensitive sensor array.
15 . The texture recognition device according to claim 10 , wherein the backlight element further comprises a reflecting sheet,
the reflecting sheet is configured to reflect light incident on the reflecting sheet to obtain reflected light, and the first backlight further comprises the reflected light,
in the first direction, the light guide plate is located between the reflecting sheet and the inverse prism sheet.
16 . The texture recognition device according to claim 10 , wherein the photosensitive element comprises a plurality of photosensitive sensors arranged in an array.
17 . The texture recognition device according to claim 1 , wherein the backlight element further comprises a reflecting sheet,
the reflecting sheet is on a side of the backlight element away from the light constraint element, and is configured to reflect light incident on the reflecting sheet to obtain reflected light, and the first backlight further comprises the reflected light.
18 . The texture recognition device according to claim 1 , wherein the preset angle range is 0 degree to 20 degrees.
19 . The texture recognition device according to claim 1 , wherein the texture of the detection object comprises a skin corresponding to a fingerprint of a user, and the texture image comprises a fingerprint image.
20 . A display device, comprising a texture recognition device,
wherein the texture recognition device comprises:
a backlight element, configured to provide first backlight;
a light constraint element, configured to perform a light divergence angle constraint process on the first backlight to obtain second backlight with a divergence angle within a preset angle range, wherein the second backlight is transmitted to a detection object; and
a photosensitive element, configured to detect the second backlight reflected by a texture of the detection object to recognize a texture image of the texture of the detection object;
wherein the backlight element comprises an edge-lit backlight light source and a light guide plate, the light guide plate is on a light exit side of the edge-lit backlight light source,
the light guide plate comprises a first light incident surface, a first light reflecting surface, and a first light exit surface, and the first light reflecting surface and the first light exit surface are oppositely arranged in a first direction,
the first light reflecting surface comprises a prism pillar structure array, the prism pillar structure array comprises a plurality of triangular prism pillars arranged in sequence along a second direction.