Micro-lens array capable of reducing optical crosstalk between pixels of polarization imaging device

Abstract

The invention provides a micro-lens array capable of reducing optical crosstalk between pixels of a polarization imaging device. The micro-lens array comprises a pixel array, a planarization layer, agrating array and a micro-lens array body; the pixel array is composed of the pixels distributed in an array; the grating array is composed of a plurality of sub-wavelength gratings which are distributed in an array; the micro-lens array body is composed of a plurality of micro-lenses which are distributed in an array. The micro-lens array is characterized in that the diameter of the micro-lensesis equal to the length of the diagonal lines of the pixels; isolation grooves are formed between every two adjacent micro-lenses, and the depth of the isolation grooves reaches the surface of the grating array. The micro-lens array has the advantages that the micro-lens array for the polarization imaging device is provided and can effectively reduce the optical crosstalk between the pixels.

Description

technical field [0001] The invention relates to a polarization imaging device, in particular to a microlens array capable of reducing optical crosstalk between image elements of the polarization imaging device. Background technique [0002] Traditional imaging technology generally achieves imaging functions by capturing wavelength and intensity information, and imaging using polarization information is an emerging field that has emerged in recent years. As we all know, light is essentially a kind of electromagnetic wave. When light is propagating, its electric field vibration deviates to a certain direction, which is the polarization characteristic of light; imaging with polarization information can provide richer scene information. When light passes through After the surface of the object is reflected, its polarization characteristics will change accordingly, so the composition information and surface characteristics of the object can be extracted from it, and the ability o...

AI Technical Summary

Problems solved by technology

[0004] In the prior art, the polarized imaging device based on the split focal plane scheme usually adopts a subwavelength grating for its miniature polarizer, and the subwavelength grating has the characteristic of analyzing polarization. Only the polarization component of the polarization component can pass through the sub-wavelength grating, and a polarization functional unit is formed by combining four sub-wavelength gratings with analysis angles of 0°, 45°, 90°, and 135° respectively and corresponding picture elements; For polarization imaging devices, the polarization extinction ratio is one of its main parameters. The polarization extinction ratio refers to the ratio of the light intensity received by a pixel in a specific polarization direction to the light intensity in other polarization directions. Since each subwavelength grating is surrounded by It is a sub-wavelength grating with other analysis angles, so the optical crosstalk between pixels must be strictly limited to ensure a high polarization extinction ratio. However, since the sub-wavelength grating also has diffraction characteristics, after the incident light enters the sub-wavelength grating, it will Into adjacent pixels under the action of diffraction, causing optical crosstalk

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