Light sensation detection device and display terminal

Abstract

The invention provides a light sensation detection device and a display terminal which are applied to the technical field of display. In the light sensation detection device, a power supply module comprises a control unit and a processing unit which are connected with each other to output a first voltage, a second voltage and a third voltage; a detection module is connected with the power supply module, and comprises a first bridge arm and a second bridge arm which are connected in parallel to receive a first voltage, a second voltage and a third voltage, an upper switching tube of the first bridge arm and a lower switching tube of the second bridge arm are photoinduction switching tubes, the midpoint of the first bridge arm outputs a first detection signal, and the midpoint of the secondbridge arm outputs a second detection signal; and the work period of the light sensation detection device comprises a first time period and a second time period, and the first voltage is higher than the second voltage in the first time period and lower than the second voltage in the second time period. According to the light sensation detection device and the display terminal, light sensation errors can be reduced, the device stability is enhanced, and the sensitivity of an automatic backlight system of the display terminal is improved.

Description

technical field [0001] The present invention relates to the field of display technology, in particular to a photosensitive detection device and a display terminal. Background technique [0002] In the existing automatic backlight adjustment system of a display terminal, the light sensing structure adopts a differential structure to improve the sensitivity and linearity of the detection result and enhance the anti-interference ability. In the use of this photo-sensing structure, the bias voltage of the differential circuit is a DC voltage. Due to the mechanism of charge trapping, the threshold voltage of the transistor device will drift with the increase of the gate biasing time, and the transfer characteristic curve will change. The overall offset, the direction of the offset is related to the polarity of the gate voltage, and the variation of the threshold voltage has a logarithmic relationship with the gate pressurization time, which leads to the error of the light sensing...

AI Technical Summary

Problems solved by technology

In the use of this photo-sensing structure, the bias voltage of the differential circuit is a DC voltage. Due to the mechanism of charge trapping, the threshold voltage of the transistor device will drift with the increase of the gate biasing time, and the transfer characteristic curve will change. The overall offset, the direction of the offset is related to the polarity of the gate voltage, and the variation of the threshold voltage has a logarithmic relationship with the gate pressurization time, which leads to the error of the light sensing signal. In the actual test, it is found that the deviation of 24 hours is within 15 -25% or so

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