Development of precision polymer molding of aspheric lens for disposable endoscope

Abstract

Low-cost disposable endoscopes are highly demanded because it is difficult to completely prevent infection by endoscopy. We propose an endoscope with an insert molded integrated optics connected to a pair of polymer optical fibers. The integrated optics consists of an aspheric imaging lens and an illumination prism. The lens forms an in-vivo image on a facet of a multicore fiber to transfer to an imaging device, while the prism illuminates target to be observed using light delivered from a single core fiber. The integrated optics is designed using ray-tracing calculations, which size is 2.5mm wide and 3.9 mm high. Furthermore, we developed facet polishing technique for polymer fiber and molding process for manufacturing. Image acquisition experiments are successfully performed using the developed optics.