CN-121978846-A - Air imaging device based on retro-reflection microstructure array

CN121978846ACN 121978846 ACN121978846 ACN 121978846ACN-121978846-A

Abstract

The invention discloses an air imaging device based on a retro-reflection microstructure array, which relates to the field of air imaging and comprises the retro-reflection microstructure array, a spectroscope, a quarter wave plate and an image source, wherein light beams emitted by the image source are reflected by a reflection polaroid, pass through the quarter wave plate and then reach the retro-reflection microstructure array, and then pass through the quarter wave plate and the spectroscope in sequence after being reflected by the retro-reflection microstructure array, so that a real image is formed in the air. The device utilizes the physical reflection and transmission characteristics of the inclined spectroscope and combines the directional reflection function of the retro-reflection microstructure array to realize light path guiding so as to realize the air imaging with large size and large visual angle of naked eyes. The elements are not overlapped in multiple layers, special interference light filtering elements are not needed, and cost is effectively reduced. The problems that the existing aerial imaging display technology is difficult to realize, the display resolution is limited by the size of the plane mirror, and residual shadows exist after imaging are solved.

Inventors

GAO XIN
YU XUNBO
WANG ZIXIAN
HE JINHONG
YAN BINBIN
SANG XINZHU

Assignees

北京邮电大学

Dates

Publication Date: 20260505
Application Date: 20260304

Claims (10)

1. An aerial imaging device based on a retro-reflection microstructure array is characterized by comprising the retro-reflection microstructure array, a spectroscope, a quarter wave plate and an image source, wherein: the quarter wave plate is covered in front of the retro-reflection microstructure array and is used for delaying the phase of the light wave; The spectroscope consists of a glass substrate and a reflective polarizer and is obliquely arranged in front of the quarter wave plate; The reflective polarizer is covered on one surface of the glass substrate facing the quarter wave plate and is used for reflecting polarized light with a set polarization direction and transmitting polarized light perpendicular to the set polarization direction; Light beams emitted by the image source are reflected by the reflective polarizer, pass through the quarter wave plate and reach the retro-reflective microstructure array, then pass through the quarter wave plate, the reflective polarizer and the glass substrate in sequence after being reflected by the retro-reflective microstructure array, and then are converged in the air to form a real image.
2. The aerial imaging device based on the retroreflective microstructure array according to claim 1, wherein the retroreflective microstructure array comprises a plurality of retroreflective microstructures, each of the retroreflective microstructures comprises a first optical structure, a second optical structure and a third optical structure which are sequentially arranged, the first optical structure faces the quarter wave plate, the first optical structure is a first plano-convex lens, the convex surface of the first convex lens faces the quarter wave plate, the second optical structure is an aperture, the third optical structure is a second plano-convex lens, the convex surface of the second plano-convex lens is far away from the second optical structure, the convex surface of the second plano-convex lens is plated with a reflective film, when light is incident from the first optical structure, refraction occurs on the surface of the first optical structure, passes through a light transmitting area in the second optical structure, reflects on the convex surface of the third optical structure and sequentially passes through the second optical structure and the first optical structure to the reflective polarizer.
3. The air imaging device based on a retroreflective microstructure array according to claim 2, wherein in the same retroreflective microstructure, the convex surface of the second plano-convex lens is a circular arc segment centered on the center point of the diaphragm, so that the distance from the center of the second optical structure to the vertex of the third optical structure is equal to the radius of curvature of the convex surface of the third optical structure.
4. The air imaging device based on a retroreflective microstructure array of claim 2 wherein the first optical structure is the same filler material as the third optical structure and the radius of curvature of the convex surface of the first optical structure and the radius of curvature of the convex surface of the third optical structure are constrained by: To ensure that the parallel light is converged at one point on the convex surface of the third optical structure, wherein For the first optical structure and the third optical structure refractive index of filling material of the structure; the distance from the convex top point of the first optical structure to the center point of the diaphragm; a radius of curvature of a convex surface that is the third optical structure; Is the refractive index of air; Is the radius of curvature of the convex surface of the first optical structure.
5. The air imaging device based on a retroreflective microstructure array of claim 4 wherein the radius of curvature of the convex surface of the first optical structure is 0.906mm and the distance from the apex of the convex surface of the first optical structure to the center point of the diaphragm is 0.843mm.
6. The air imaging device based on retroreflective microstructure array of claim 4 wherein the radius of the light transmitting area of the diaphragm is 0.3mm.
7. The air imaging device based on retroreflective microstructure array of claim 4 wherein the filler material refractive index of the first and third optical structures is 1.61.
8. The air imaging device based on retroreflective microstructure array of claim 4 wherein the angle of incidence of the retroreflective microstructures The range of (2) is: Wherein the method comprises the steps of An arctangent function; is the radial thickness of the retroreflective microstructures; a sagittal height of the convex surface of the third optical structure; is the distance from the center of the second optical structure to the apex of the third optical structure.
9. The air imaging device based on a retroreflective microstructure array of claim 8 wherein the radius of curvature of the convex surface of the third optical structure is 1.434mm and the sagittal height of the convex surface of the third optical structure is 0.195mm.
10. The retroreflective microstructure array-based aerial imaging device of claim 1 wherein the beam splitter is tilted at 45 °.

Description

Air imaging device based on retro-reflection microstructure array Technical Field The invention relates to the field of aerial imaging, in particular to an aerial imaging device based on a retro-reflection microstructure array. Background The aerial imaging display device can realize the off-screen display effect that the display content is suspended in the air, the display content and the display screen are not simultaneously appeared in the field of view, the display effect is more real, the space dimension of display is expanded, the viewing experience of more natural immersion can be provided for viewers, and the device has wide application in the fields of commercial display, cultural exhibition, entertainment and the like. The current aerial imaging display technology mainly comprises a space voxel display technology, a foldback display technology based on a curved surface reflector or a large-caliber lens and an air imaging technology based on a negative refractive index flat lens. The space voxel display technology is to construct voxels which can be watched at 360 degrees from all angles in space by constructing a luminous lattice or a projection screen in a high-speed rotating scanning imaging mode through laser ionization, and has high realization difficulty and high requirements on environment and devices, and is currently in research and experimental stages. The air imaging technology based on the negative refractive index flat lens realizes the imaging effect that object points and image points are distributed on two sides of the array through a micro-size plane mirror array, but the display resolution under the structure is limited by the size of the plane mirror, and after imaging, residual shadows exist, so that the viewing experience of a viewer is affected. Disclosure of Invention Aiming at the defects in the prior art, the air imaging device based on the retro-reflection microstructure array solves the problems that the existing air imaging display technology is difficult to realize, the display resolution is limited by the size of a plane mirror, and residual shadows exist after imaging. In order to achieve the aim of the invention, the invention adopts the following technical scheme: an aerial imaging device based on a retro-reflection microstructure array is provided, which comprises the retro-reflection microstructure array, a spectroscope, a quarter wave plate and an image source, wherein: the quarter wave plate is covered in front of the retro-reflection microstructure array and is used for delaying the phase of the light wave; The spectroscope consists of a glass substrate and a reflective polarizer and is obliquely arranged in front of the quarter wave plate; The reflective polarizer is covered on one surface of the glass substrate facing the quarter wave plate and is used for reflecting polarized light with a set polarization direction and transmitting polarized light perpendicular to the set polarization direction; Light beams emitted by the image source are reflected by the reflective polarizer, pass through the quarter wave plate and reach the retro-reflective microstructure array, then pass through the quarter wave plate, the reflective polarizer and the glass substrate in sequence after being reflected by the retro-reflective microstructure array, and then are converged in the air to form a real image. Further, the retroreflective microstructure array comprises a plurality of retroreflective microstructures, each retroreflective microstructure comprises a first optical structure, a second optical structure and a third optical structure which are sequentially arranged, and the first optical structure faces the quarter wave plate; the first optical structure is a first plano-convex lens, the convex surface of the first convex lens faces the quarter wave plate, the second optical structure is a diaphragm, the third optical structure is a second plano-convex lens, the convex surface of the second plano-convex lens is far away from the second optical structure, the convex surface of the second plano-convex lens is plated with a reflecting film, when light rays enter from the first optical structure, refraction occurs on the surface of the first optical structure, passes through a light transmission area in the second optical structure, and is reflected on the convex surface of the third optical structure and sequentially passes through the second optical structure and the first optical structure to be directed to the reflecting polaroid. Further, in the same retroreflective microstructure, the convex surface of the second plano-convex lens is an arc segment centered on the center point of the diaphragm, so that the distance from the center of the second optical structure to the vertex of the third optical structure is equal to the radius of curvature of the convex surface of the third optical structure. Further, the first optical structure is the same as the filler material of t