Optical fingerprint recognition device and display device

Abstract

The invention discloses an optical fingerprint recognition device and a display device. The optical fingerprint recognition device comprises a light source, a light guide plate, a first volume grating, a second volume grating, and a light detector. The light guide plate comprises two parallel light guide surfaces. The first and second volume gratings are located on the light guide surfaces of the light guide plate. The light source is located at one side, backing on to the first volume grating, of the light guide plate. The light detector is located at one side, backing on to the second volume grating, of the light guide plate. During fingerprint recognition, a detected finger makes contact with the light guide surface of the light guide plate, and the light detector recognizes the fingerprint of the detected finger through detecting the light intensity distribution of the light from the second volume grating. Because the reflection light in the light guide surfaces is much higher in intensity than the diffuse reflection light of the finger and is not liable to be affected by the external light and the difference, corresponding to the ripples of the fingerprint, of the reflection light is more apparent, the device employs the reflection light of the light guide surface making contact with the finger for determining the light intensity distribution corresponding to the fingerprint, so as to achieve the higher accuracy of fingerprint recognition.

Description

technical field [0001] The invention relates to the field of display technology, in particular to an optical fingerprint identification device and a display device. Background technique [0002] With the development of fingerprint identification technology, it has been widely used in many fields, such as mobile phones, tablet computers and TVs in electronic equipment terminals; access control and safes in security protection systems. The realization methods of fingerprint collection mainly include optical, capacitive and ultrasonic imaging technologies, among which the optical fingerprint recognition technology has a relatively large recognition range and relatively low cost. [0003] At present, the optical fingerprint recognition technology used in liquid crystal displays (LCD) including mobile phones and other mobile terminals is still immature. Usually, backlight panels and optical imaging devices are used for diffuse reflection fingerprint imaging. The principle is that...

AI Technical Summary

Problems solved by technology

However, due to the low transmittance of the LCD, the light energy received by the photoelectric detection in the LCD is extremely low, and the light energy difference between the trough and the peak of the fingerprint diffusely reflected back to the sensor is very small, and the trough There is light interference between the ridge and the ridge, which makes it difficult for the detection system to identify the fingerprint, resulting in low accuracy of fingerprint identification

Images