Design and Fabrication of Computer Generated Hologram for Virtual Projection of a Reticle Pattern

In this paper, we present the design and fabrication of an on-axis Fresnel Computer Generated Hologram (CGH) which on illuminating with the laser diode projects the virtual image of a reticle pattern. This can find application in an aiming sight where the reticle pattern is projected onto a distant target. An iterative optimization algorithm has been used to design the CGH. The CGH of about 20 mm size with 5 microns pixel size is fabricated using a maskless lithography system.