Realization of fabricating microlens array in mass production

Micro-electro-mechanical system technology offers a wide number of applications for the military, industrial, and consumer markets. The miniaturization of components is a common objective for ail studies. Refractive microlens array with density 400 lenses per cm(2) are fabricated in three minutes by using hot embossing. The higher accuracy and lower cost of microlens fabrication methods are needed to meet the rapid growth of commercial devices. Higher density of microlens is achievable by a higher density mesh mold. Microlens diameters of 250 similar to 380 mu m are shaped with various molds. Focal lengths of 185 similar to 225 mu m are obtained by changing compression pressure and working temperature which are discovered in this experiment. Molding temperature effects on the surface tension in lens material as explored is essential. Form accuracy of microlens arrays are less than Rt 0.1 mu m that adapt to the form accuracy of the lenses. This article describes a mass fabricating method for microlens array by using hot embossing and the experimental results show its feasibility for practice.