Several approaches to fabricate micro optical elements by use of half tone masks are studied and compared. It is shown that half tone masks employed in filtering image systems can obtain gray patterns with considerabl...Several approaches to fabricate micro optical elements by use of half tone masks are studied and compared. It is shown that half tone masks employed in filtering image systems can obtain gray patterns with considerably high precision, but it is hard to operate from the viewpoint of operation. The method using contacting lithography technology or laser ablation can be easily operated with the cost of reducing fabrication precision and the trouble of choosing appropriate materials. For all of these methods, the coding of half tone masks with corrections for the nonlinear characteristics of coding, imaging and photoresist is recommended.展开更多
＂Hollow mask illusion＂ is an optical illusion and appears due to an error in the process of reconstructing the three-dimensional objects from our two-dimensional retinal image. In this paper, we present a computatio...＂Hollow mask illusion＂ is an optical illusion and appears due to an error in the process of reconstructing the three-dimensional objects from our two-dimensional retinal image. In this paper, we present a computational method to create ＂Hollow mask＂ type new illusionary solid by calculating the hollow structure and its shading. The straight line Voronoi diagram for a given shape obtains the three-dimensional vertices of the hollow structure and the shading effect on each surface is calculated under the assumption that each surface has diffusely reflecting surface（Lambertian reflectance）. We also show two examples of our new illusionary solid works.展开更多
基金supported by 973 Program of China under Grant No.2006CB302900part by the National Natural Science Foundation of China under Grant No.60825405 and No.60778018
文摘Several approaches to fabricate micro optical elements by use of half tone masks are studied and compared. It is shown that half tone masks employed in filtering image systems can obtain gray patterns with considerably high precision, but it is hard to operate from the viewpoint of operation. The method using contacting lithography technology or laser ablation can be easily operated with the cost of reducing fabrication precision and the trouble of choosing appropriate materials. For all of these methods, the coding of half tone masks with corrections for the nonlinear characteristics of coding, imaging and photoresist is recommended.
文摘＂Hollow mask illusion＂ is an optical illusion and appears due to an error in the process of reconstructing the three-dimensional objects from our two-dimensional retinal image. In this paper, we present a computational method to create ＂Hollow mask＂ type new illusionary solid by calculating the hollow structure and its shading. The straight line Voronoi diagram for a given shape obtains the three-dimensional vertices of the hollow structure and the shading effect on each surface is calculated under the assumption that each surface has diffusely reflecting surface（Lambertian reflectance）. We also show two examples of our new illusionary solid works.
