Fong-Zhi CHEN^*, Cheng-Huan CHEN¹, Cheng-Hsien WU², Ching-Hsiang KUO, Jyh-Rou SZE, Wei-Yao HSU, and Yuan-Chieh CHENG

Instrument Technology Research Center, National Applied Research Laboratories, No. 20 R&D Rd. VI, Hsinchu Science Park, Hsinchu 300, Taiwan ¹Department of Power Mechanical Engineering, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 300, Taiwan ²Department of Mold and Die Engineering, National Kaohsiung University of Applied Sciences, No. 415 Chien Kung Road, Kaohsiung 807, Taiwan

(Received December 27, 2010; Accepted May 10, 2012)

This paper introduces the development of a double-sided micro lens array (DSMLA) for application in micro laser projectors. For commercial mass production, it is necessary to investigate the concurrent engineering of optical design, mold fabrication, and plastic injection molding at once. This experiment based the design of the micro lens array on the scalar diffraction theory. The proposed DSMLA can simultaneously shape red, green, and blue laser beams into a uniform projection pattern. An ultra precision diamond turning machine using a slow tool servo method fabricated the mold. The study considered optical design constraints from the feedback of mold fabrication and plastic injection molding, measuring and comparing fabricated samples with calculated results. Experimental results show that the fabricated DSMLAs achieve the desired function and application feasibility for micro laser projectors.

Key words: double-sided micro lens array, micro laser projector

^*E-mail address: chen@itrc.narl.org.tw