Ultra-thin parallel light source based on Fresnel zone plate array

Abstract

The invention discloses an ultra-thin parallel light source based on a Fresnel zone plate array. The ultra-thin parallel light source is characterized by including a luminescent source, a small hole aperture array, and a first Fresnel zone plate array, which are successively arranged in parallel, wherein light emitted by the luminescent source diffuses in all directions and exits from small holesof the small hole aperture array to form a point light source array, and light emitted by the point light source array is diffracted by the Fresnel zone plate array to form parallel light. Compared with an existing parallel light source of a double telecentric structure, the ultra-thin parallel light source based on the Fresnel zone plate array has the advantages of small axial distance, light weight, low cost, and simple assembly of a large area parallel light source.

Description

technical field [0001] The invention relates to a parallel light source, in particular to an ultra-thin parallel light source based on a Fresnel zone plate array. Background technique [0002] Parallel light sources can be used in many occasions, such as industrial microstructure inspection, backlight of near-eye display devices, etc. Most of the collimated light sources on the market today use optical structures such as bi-telecentricity to manufacture collimated light sources, such as figure 1 As shown, such a structure has a long axial distance of the optical axis in terms of volume, and is inconvenient to carry and assemble. And there is a problem that the area of ​​the light source is not large, because when the area of ​​the light source becomes larger, the diameter, radius of curvature, and axial distance of the assembly of the convex lens will also increase accordingly, so that the production difficulty, production cost, and installation cost of the large-sized lens...

AI Technical Summary

Problems solved by technology

Most of the collimated light sources on the market today use optical structures such as bi-telecentricity to manufacture collimated light sources, such as figure 1 As shown, such a structure has a long axial distance of the optical axis in terms of volume, and is inconvenient to carry and assemble.

And there is a problem that the area of ​​the light source is not large, because when the area of ​​the light source becomes larger, the diameter, radius of curvature, and axial distance of the assembly of the convex lens will also increase accordingly, so that the production difficulty, production cost, and installation cost of the large-sized lens will increase. sharp increase

Moreover, such a parallel light source with a long axial distance cannot be used in many scenes with strict volume requirements, such as the above-mentioned near-eye display device backlight, etc.

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