A method for manufacturing a flexible variable-angle array diffractive optical device made of PDMS material

Abstract

The invention provides a fabrication method of a flexible variable-angle array diffractive optical device made from a PDMS material. The method comprises the following steps that firstly, a mask of the flexible variable-angle array diffractive optical device containing N groups of one-dimensional binary diffractive optical structures is well prepared; secondly, a silicon wafer is selected as a substrate material and cleaned; thirdly, the silicon wafer is coated with photoresist so as to form a photoresist diffraction pattern; fourthly, the photoresist pattern is subjected to surface rougheningby using dry etching equipment; fifthly, liquid PDMS is prepared; sixthly, the liquid PDMS is dripped into a photoresist structure; seventhly, after the sixth step, the photoresist structure patternis transferred to the PDMS material and becomes solid; eighthly, the solidified PDMS material is stripped from the photoresist structure, and the flexible variable-angle array diffractive optical device is fabricated. The fabrication method is good in all-band speckle reduction effect, simple in motion mode, easy to implement, good in system universality and robustness and low in cost.

Description

technical field [0001] The invention belongs to the field of laser display projection, and in particular relates to a method for manufacturing a flexible variable-angle array diffractive optical device made of PDMS (polydimethylsiloxane) material. Background technique [0002] Laser projection display system is getting more and more attention and welcome because of its rich colors, high picture quality, long life, high reliability, high efficiency, low energy consumption and other advantages. However, since laser light is highly coherent light, a picture noise called laser speckle will inevitably be generated. Speckle appears as black spots randomly distributed in the laser spot, and its essence is the random coherent superposition of signals. The existence of speckle seriously affects the quality of images and information. In the field of laser projection display, speckle will degrade the image quality of projection display, cause viewers to experience symptoms such as fat...

AI Technical Summary

Problems solved by technology

[0005] In order to overcome the disadvantages of the prior art that the speckle suppression effect is not good enough, full-band speckle suppression cannot be performed, the number and types of devices used in the system are large, the moving parts are complex and have impact damage to the instrument, the size is large, the structure of the instrument is complex, and the energy consumption is high. , the present invention provides a method for manufacturing a diffractive optical device with good full-band speckle suppression effect, simple movement mode, easy implementation, system versatility, good robustness, and low cost, using polydimethylsiloxane ( PDMS) materials, through variable-angle array diffraction structure, to build a crawler transmission that can circulate infinitely at a constant speed instead of reciprocating mechanical movement to achieve red, green, blue full-band laser speckle suppression

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