US 12,424,022 B2
Display panel and display device
Chuan Shuai, Hubei (CN); Guiyang Zhang, Hubei (CN); and Yaqiong Long, Hubei (CN)
Assigned to WUHAN CHINA STAR OPTOELECTRONICS TECHNOLOGY CO., LTD., Hubei (CN)
Appl. No. 17/297,545
Filed by WUHAN CHINA STAR OPTOELECTRONICS TECHNOLOGY CO., LTD., Hubei (CN)
PCT Filed May 18, 2021, PCT No. PCT/CN2021/094313
§ 371(c)(1), (2) Date Jan. 3, 2024,
PCT Pub. No. WO2022/227133, PCT Pub. Date Nov. 3, 2022.
Claims priority of application No. 202110467234.7 (CN), filed on Apr. 28, 2021.
Prior Publication US 2024/0127623 A1, Apr. 18, 2024
Int. Cl. G06V 40/13 (2022.01); G02B 27/30 (2006.01)
CPC G06V 40/1329 (2022.01) [G02B 27/30 (2013.01); G06V 40/1318 (2022.01)] 20 Claims
OG exemplary drawing
 
1. A display panel, comprising:
a fingerprint recognition area, a cover plate, and an optically transparent layer, wherein the optically transparent layer at least covers a portion of the cover plate disposed in the fingerprint recognition area, a refractive index of the optically transparent layer is greater than a refractive index of air and less than a refractive index of a finger and a refractive index of the cover plate, and an optical thickness of the optically transparent layer is an even multiple of a half-wavelength of a fingerprint recognition light ray,
wherein the optically transparent layer comprises a first surface on a side adjacent to the cover plate and a second surface on a side opposite to the cover plate,
wherein the optically transparent layer is configured such that:
when a fingerprint recognition light ray is reflected from the first surface and the second surface thereof at valleys of a fingerprint in contact with the optically transparent layer, the reflected fingerprint recognition light rays have a phase difference that is an integer multiple of 2π, and constructively interfere; and
when a fingerprint recognition light ray is reflected from the first surface and the second surface thereof at ridges of the fingerprint in contact with the optically transparent layer, the reflected fingerprint recognition light rays have a phase difference that is an odd multiple of x due to a half-wave loss at the second surface, and destructively interfere, thereby increasing a fingerprint recognition contrast between the ridges and the valleys of the fingerprint.