DEVELOPMENT OF HIGH THROUGHPUT PLASTIC MICROLENSES USING A REPLACEABLE INJECTION MOLD DISK
The objective of this work is to develop plastic microlenses using high throughput injection molding techniques. In this work, plastic microlenses have been designed, fabricated and characterized for future applications in optical communications and biochemical chip detection systems. Microlenses, that have wide ranging applications in image processing, displays, communications and biochemical detection have been researched for the past two decades. Various fabrication techniques have been developed using a wide range of materials. Plastic as a material for fabricating microlenses has been investigated in recent years. Soft lithography and hot embossing are examples of two of the techniques that have been used to fabricate plastic microlenses. The primary reason for using plastics as the material is their potential for high volume replication at a very low cost. However, a suitable technique for high volume fabrication of plastic microlenses has not been optimized yet. This work has successfully implemented a fabrication technique that enables high volume replication of plastic microlenses using injection molding techniques. A replaceable injection mold disk was fabricated using metal electroforming. The initial microlens mold was realized using the photoresist reflow technique. The fabricated mold disk was used as the master mold for the injection molding process. The microlenses were fabricated using two new plastics, COC and Poly IR 2 that have excellent optical transparency in the visible and infrared wavelength regions respectively. The plastic microlenses were characterized in terms of their focal lengths and surface roughness. The plastic microlenses developed in this work hold lot of promise for numerous applications in optical communications and biochemical detection.
School:University of Cincinnati
School Location:USA - Ohio
Source Type:Master's Thesis
Keywords:mems microlenses plastic micromachining injection molding electroforming
Date of Publication:01/01/2003