There are several reasons why LCD screens cannot display under screen fingerprints.
Firstly, under screen fingerprint recognition technology is typically based on optical or ultrasonic principles. For optical under screen fingerprint recognition, it requires the screen to emit specific light, illuminate the fingerprint area through the screen, and then receive the reflected light to recognize the fingerprint. However, due to its structural characteristics, LCD screens cannot achieve local self illumination like OLED screens. LCD screens provide light through backlighting, and the backlight of the entire screen cannot be precisely controlled locally, making it difficult to illuminate the fingerprint area and obtain clear fingerprint images.
Secondly, the thickness of LCD screens is relatively thick. Under screen fingerprint recognition requires the installation of a fingerprint recognition sensor below the screen, and a thicker LCD screen will increase the distance between the sensor and the finger, resulting in severe signal attenuation and affecting the accuracy and sensitivity of fingerprint recognition. In contrast, OLED screens are thinner and can better adapt to the installation requirements of under screen fingerprint recognition sensors.
In addition, the pixel structure of LCD screens is not conducive to under screen fingerprint recognition. The pixels of an LCD screen are composed of liquid crystal molecules and color filters, which can interfere with the transmission and reflection of light, making fingerprint recognition signals more complex and difficult to process. The pixel self luminous characteristics of OLED screens can reduce this interference and improve the effectiveness of fingerprint recognition.
In summary, due to the limitations of the backlight structure, thickness, and pixel structure of LCD screens, it is currently difficult to achieve under screen fingerprint recognition function.
