Metamaterial motion-sensing holographic element and design method thereof

Abstract

The invention discloses a metamaterial motion-sensing holographic element and a design method thereof. The motion-sensing holographic element comprises a substrate, and periodically distributed silicon nano brick array units are etched on the work face of the substrate. The sizes of silicon nano bricks in the silicon nano brick array units are equal, the orientation angle phi(x,y) of the silicon nano bricks is theta(x,y) / 2, theta(x,y) is the phase of corresponding pixels (x,y) of the silicon nano bricks, and center gaps between adjacent silicon nano bricks in the x direction and the y direction are equal. By means of the element and the design method, continuous phase modulation can be achieved on incident light. The process is simple, and the element has the outstanding advantages of being excellent in performance, high in stability, good in reliability, easy to manufacture and the like.

Description

technical field [0001] The invention belongs to the technical field of micro-nano optics and optical holography, and in particular relates to a metamaterial somatosensory holographic element and a design method thereof. Background technique [0002] Somatosensory technology is an active human motion recognition technology that has been popular in recent years. It uses optical cameras and image processing algorithms to quickly identify the characteristics of human movement. It can be applied to somatosensory games, human-computer interaction, video Important science and technology in the fields of monitoring and intelligent perception. The image in the somatosensory technology is not a simple scene image, but uses holographic technology to irradiate a beam of collimated laser light on the holographic element, and then forms a random array of light spots on the human body. The image processing algorithm recognizes human body movements in the image. It is the identification of...

AI Technical Summary

Problems solved by technology

At present, the binary step structure with only one depth value is most commonly used, and its manufacturing process and replication technology are relatively simple; but because there are only two simple phase adjustment functions of 0 and π, its image signal-to-noise ratio (SNR) It is difficult to improve, so it puts great pressure on the subsequent narrow-band filtering, image processing, etc.

Holographic elements with multi-step structures (4, 8, 16 steps are the most common) can alleviate this problem, but at the cost of process complexity (requires multi-step overlay process, or complex electron beam direct writing process); and for This complex multi-step structure, on the one hand, will reduce performance due to manufacturing errors, and on the other hand, it will cause a lot of trouble for device replication

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