Imaging of Micro Half Conical Lens Fabricated by Using Ball End Milling Machining

By ball-end milling processes, die base with cavity of half conical shape is fabricated on an aluminum block. With the plastic materials heated to melt and filling the mold, half conical lens is formed as plastic material cooling and solidifying. Due to various curvature of conical shape, different incident angles will produce some types of projecting images. The lens can change the laser spot to one fork light sheet which is line-like image. Moreover, it can further split the one fork line-like image to two folks light sheet which is a cross line image or "X" shape image. It is obvious that the larger incident angle would induce "X" shape image. With the smaller incident angle and more parallel to incline of the conical surface, the image would be a light spot. From this study, it is found that CNC machining can fabricate micro conic lenses successfully. It can be used to machine lenses with complex surface practically.