Design and Fabrication of Micro Aspherical Lens for Optical Pickup Head

• Main Authors: Chiung-Ting Chen, 陳炯廷
• Other Authors: Fan-Gang Tseng
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/34406559231277733538

碩士 === 國立清華大學 === 微機電工程研究所 === 94 === This paper proposes a novel design concept and fabrication method of micro aspherical lens for Optical pickup head. Gradient-Electrostatic-Forces (GEF) were employed to shape liquid polymer from hemisphere into parabolic or near cone shape, and the shape can be fixed by a UV curing process in situ. As a result, the numerical aperture for this lens was varied from 0.49 at spherical shape into 0.66 at near parabolic shape and the focused light spot size (by red light 632.8nm) was reduced from 2.302 μm into 1.166 μm, suitalbe for the need of objective lenses with high mumerical apertures and resolution. Very high quality focus effects, 0.778 μm spot size (by red light 632.8nm), and 0.66 NA were obtained at an optimized shape of the GEF lens, which is compatible to those of the commercial DVD objective lens.