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, and the edge-lit backlight light source is arranged on a side surface, which is perpendicular to a first light exit surface of the light guide plate, 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,

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 to obtain the second backlight, wherein divergence angle of the part first backlight is within the preset angle range, and the plurality of hollowed-out regions are arranged in an array;

wherein the light constraint element is on a side of the backlight element close to the photosensitive element, and the light constraint element is between the photosensitive element and the backlight element;

wherein the light guide plate and the edge-lit backlight light source are arranged along a direction, and in the direction, a density of hollowed-out regions, among the plurality of hollowed-out regions, on a side of the collimating film close to the edge-lit backlight light source is less than a density of hollowed-out regions, among the plurality of hollowed-out regions, on a side of the collimating film away from the edge-lit backlight light source;

wherein the light guide plate comprises a first light incident surface, a first light reflecting surface, and the 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 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 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,

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,

the first light reflecting surface comprises a first side surface of each triangular prism pillar, a second side surface of each triangular prism pillar, and a spacing surface between two adjacent triangular prism pillars,

a first base angle of each triangular prism pillar on a side of each triangular prism pillar close to the first light exit surface ranges from 80 degrees to 90 degrees, and a second base angle of each triangular prism pillar on the side of each triangular prism pillar close to the first light exit surface ranges from 1 degree to 2.5 degrees.