3D Image Based On Double Cemented Microlens Array

3D image display technology based on microlens array has the advantages of simple structure and continuous parallax,and has important application value in visual anticounterfeiting,advertising printing and so on.Microlens array and light field image array are two key devices to realize 3D image.In the current study,the microlens array used for 3D image display usually has only one refractive surface,resulting in a limited viewing angle with motion parallax.In terms of light field image array generation,the traditional method of multi-view parallax image synthesis has problems such as computational redundancy and slow pixel mapping.In this thesis,the design and fabrication method of double-cemented microlens array with two refractive surfaces is studied,the light field image array generation technology based on ray tracing is developed,and the 3D image display effect is tested and evaluated.The main research contents of this paper are as follows:(1)A double cemented microlens array is designed,and the effect of process tolerance on optical properties is theoretically analyzed.Compared with the traditional microlens array based on a single-layer refractive surface,the spatial resolution of 3D images under a large field of view is greatly improved.Based on the maskless layered exposure technology,the photolithography method of aspherical microlens arrays was explored,and the UV nanoimprinting process for high-precision alignment of double-layered microlens arrays was developed,and the preparation of double-coated microlens arrays was realized.(2)Based on the pixel mapping relationship in the traditional light field image array generation algorithm,combined with the ray tracing technology in computer graphics,to find the farthest collision point when the light collides with the object,and develops no computational redundancy without pixel mapping.The light field image array generation algorithm reduces the rendering time of light field image arrays.Render time is only related to scene complexity and light field image array resolution.(3)Based on laser direct writing technology and UV nanoimprinting technology,a light field image array with higher than 12000 dpi was prepared.Combined with the double cemented micro-lens array,the stereo image effect with correct occlusion relationship and continuous motion parallax is realized,and the field of view is up to 50°.The experimental results verify the correctness and feasibility of the design method of the double cemented microlens array and the light-field image array generation algorithm based on ray tracing,which provides a feasible new idea for realizing 3D images with large viewing angles.