Method and apparatus for modulating backlight source, lamp strip, backlight module, and display apparatus

Abstract

The embodiments of the invention provide a method and apparatus for modulating a backlight source, a lamp strip, a backlight module, and a display apparatus, and relate to the technical field of display, for reducing noise output by a backlight source. The method of modulating backlight comprises inputting periodic AC voltages into the backlight source within image-frame time so as to enable the backlight source to be periodically turned on and turned off. The method is applied to a display apparatus with a fingerprint or palm print identification function.

Description

technical field [0001] The invention relates to the field of display technology, in particular to a method and device for modulating a backlight source, a light bar, a backlight module, and a display device. Background technique [0002] With the continuous improvement of living standards, display devices such as mobile phones and computers have become necessities of life. Currently, there are various types of display devices on the market, and consumers are constantly pursuing display devices with good performance, high safety, and novel and unique appearance. [0003] For security, it is mainly realized by fingerprint or palmprint recognition function. Because each person's fingerprint or palmprint is different, that is, fingerprint or palmprint is unique and will remain unchanged for life, so it is used for security verification. [0004] Based on this, the inventor proposes to install a photosensitive device in the display device to realize the recognition of fingerpri...

AI Technical Summary

Problems solved by technology

[0005] However, in the liquid crystal display device, the light emitted by the backlight source in the backlight module such as LED (Light Emitting Diode, light-emitting diode) is in the visible light band, and its luminous intensity is determined based on the input voltage. During the time, that is, within one image frame time T, the voltage driving the LED is as follows Figure 1a As shown, however, due to external or device reasons, a lot of uncertain noise will be introduced, and these noises will be input into the LED with the driving voltage, and then output together with the visible light emitted by the LED

Since fingerprint recognition relies on the light emitted by LEDs, such as Figure 1b As shown, in the identification process, in addition to the light emitted by the driving voltage input to the LED incident on the valley and ridge, and projected on the photosensitive device to generate current, the light emitted by the above-mentioned noise input to the LED will also be incident on the valley and ridge. Ridge, and projected on the photosensitive device to generate a corresponding current, which will cause current fluctuations in the identification process, and thus cause identification difficulties

Images