Selecting method and selecting device for light energy conversion gain of photodiode in CMOS (complementary metal oxide semiconductor) sensor

Abstract

The invention discloses a selecting method and a selecting device for light energy conversion gain of a photodiode in a CMOS (complementary metal oxide semiconductor) sensor. The selecting method includes: computing a light intensity value, wherein the light intensity is related to image brightness Y, exposure time TEXP and current light energy conversion gain FD and second gain of the photodiode; and selecting the light energy conversion gain matched with the light intensity value from a light energy conversion gain series, wherein the light energy conversion gain series comprises at least two types of light energy conversion gain. The selecting device comprises a light intensity value computing unit and a light energy conversion gain selecting unit. According to the method and the device, the proper light energy conversion gain can be intelligently selected according to different light intensities, so that the contradictions of yellow belts in highlight and poor sensitivity in dark light can be effectively overcome.

Description

technical field [0001] The invention relates to a CMOS sensor, in particular to a method and a device for selecting a light energy conversion gain of a photosensitive diode in a CMOS sensor. Background technique [0002] Integrated circuit technology has penetrated into various fields. In the field of imaging, CCD and CMOS sensors are two commonly used image sensors. Both of them use photodiodes to perform photoelectric conversion and convert images into digital data. The main difference lies in the way digital data is transmitted. The charge data of each pixel in each row in the CCD sensor will be transmitted to the next pixel in turn, output from the bottom part, and then amplified and output by the amplifier on the edge of the sensor; in the CMOS sensor, each pixel will be adjacent to each other. An amplifier and A / D conversion circuit output data in a manner similar to a memory circuit. Compared with traditional CCD technology, CMOS sensors can better meet users' incre...

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Problems solved by technology

[0006] How to solve the contradiction between the yellow band under high light and the insufficient sensitivity under dark light, which is difficult to reconcile, has become an urgent problem to be solved by those skilled in the art

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