Large-size image sensor and image correction method thereof

Abstract

The invention provides an image sensor and an image correction method thereof. The whole pixel array of an image sensor chip is divided into multiple sub-arrays; after the image sensor chip is encapsulated and before the delivery, a test is carried out so that a fitting value of each sub-array in different light intensities is obtained and written into an internal storage unit of the image sensorchip; and after the image sensor chip is delivered and used for outputting images, corresponding fitting values can be called automatically from the internal storage unit to correct output of the sub-arrays correspondingly, so corrected images are output. Thus, image uniformity of the image sensor is improved.

Description

technical field [0001] The invention relates to the technical field of image sensors, in particular to a large-scale image sensor and an image correction method thereof. Background technique [0002] An image sensor or photosensitive element is a device that converts an optical image into an electronic signal, and it is widely used in digital cameras and other electronic optical devices. With the development of modern industry and the increase of human needs, the pixels of image sensors are increasing day by day, and when the pixels reach tens of millions or even tens of millions, the entire image sensor will reach a huge size of centimeters or even decimeters, that is, For large-size image sensors, there is a large difference in the ratio of pixels between large-size image sensors and normal-size image sensors on the wafer, such as figure 1 as shown, figure 1 shows the difference in the proportion of pixels on a wafer between a large-scale image sensor with 50 million pix...

AI Technical Summary

Problems solved by technology

[0003] The current large-size image sensors generally suffer from poor image uniformity, mainly due to:

[0004] 1. The pixels and physical size of large-size image sensors are greatly increased compared with normal-size image sensors, resulting in poor image uniformity;

[0005] 2. From the perspective of semiconductor manufacturing process, due to the limitation of semiconductor process capability, there are differences in pixels from the center to the edge within a wafer, and there are also differences in different degrees between different wafers. pixel difference

For a normal megapixel image sensor chip, because the chip size is small, these pixel differences inside a single chip do not have a great impact on image uniformity, but for a large-size image sensor, its size increases to tens of millions. When the number of pixels is large, the difference of the pixels inside the chip will be too large to be ignored, which will make the image uniformity worse.

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