Micro lens capable of reducing signal crosstalk

Abstract

The invention discloses a micro lens capable of reducing signal crosstalk, and the micro lens provided by the invention is used for solving the problem of signal crosstalk caused when the long-wavelength visible lights with the wavelength greater than 700 nm are converged and dispersed by a convex lens in a small-pixel CCD (charge coupled device) and signal electrons are generated in an adjacent pixel. The micro lens disclosed by the invention is of a concave-convex combined optical structure, wherein a small-curvature convex lens is arranged in the middle of the pixel, and a large-curvature concave lens is adopted on the edge of the pixel. The micro lens disclosed by the invention can converge the lights on a relatively deep position below the pixel so as to reduce the probability of optical crosstalk of the long-wavelength visible lights; the lights can be dispersed to each independent pixel due to the large-curvature concave lens on the edge of the pixel; and meanwhile, the probability of optical crosstalk of the obliquely-incident lights and the probability of crosstalk of the CCD can be reduced so as to improve an MTF (modulation transfer function).

Description

[0001] technical field [0002] The invention relates to a microlens used in a charge-coupled element CCD imaging system, in particular to a microlens capable of reducing signal crosstalk. Background technique [0003] In a charge-coupled device CCD (hereinafter referred to as CCD) imaging system, it usually includes two parts: a lens and a CCD. The lens transmits the external light image to the CCD, so that the photosensitive material on the CCD changes, thereby converting the optical signal into an electrical signal, and converting the image pixel into a digital signal. Generally, the part of the CCD that can perceive optical signals and convert them into electrical signals is called a photosensitive picture element or pixel, and the vertical space between photosensitive picture elements is called a channel resistance. There are many neatly arranged picture elements on the CCD, which can sense light and convert light images into digital signals. Generally, the more pixel...

AI Technical Summary

Problems solved by technology

[0005] In order to overcome the problem that the convex lens in the small-pixel charge-coupled device CCD system in the prior art converges the long-wave visible light with a wavelength greater than 700nm and then diverges and generates signal electrons in adjacent pixels to cause signal crosstalk. microlenses

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