This paper presents the fabrication and test of a micro-lens array (MLA) made of quartz substrate and UV adhesive. Numerical analysis of optics was used to find the optimal design parameters such as radius of curvature and etching depth of the micro lens. The fabricated device has an array of 1024×768 lenses. The dimension of each lens is 13.68μm×13.68μm. A quartz substrate which is a stable material at harsh environment was etched isotropically with buffered oxide etchant (BOE). We found the optimal wet etching time of quartz. We spin-coated UV adhesive on quartz substrate to complete the micro-lens array. The fill factor was almost 100%. The focal length depending on the radius of curvature and thickness of UV adhesive is in the range from 28.1 to 45.4μm. The FWHM (full width at half maximum) of the spot size is about 1.5μm in case of the sample etched for 95min at 23°C and 50% absolute humidity. Experimental tests demonstrated that each lens is fabricated successfully.
Financed by the National Centre for Research and Development under grant No. SP/I/1/77065/10 by the strategic scientific research and experimental development program:
SYNAT - “Interdisciplinary System for Interactive Scientific and Scientific-Technical Information”.