Slit-lamp用非球面前置レンズ

An Aspheric Minus Pre-Set Lens for Slit Lamp Fundus Microscope

諸言

　従来困難であつた非球面製作法の最近の進歩^1）〜4）と相まつて検眼レンズ^5），眼底カメラ光学系^6）あるいは白内障患者用眼鏡レンズ^7）〜8）などに非球面が実用化されるに至つている。

　今回，Slit lampがその立体的観察により前眼部の観察に用いられる他面に，後眼部観察に重要な役割りを果している実情から，マイナス前置レンズに検討を加え，設計製作したので報告する。

Two types of minus pre-set lenses for slit-lamp biomicroscopy of the fundus have been de-signed and fabricated.

1. A bi-concave lens with quadratic surfaces was devised to attain minimum deviation of the fundus image. This type has the drawback that it causes slightly more reflex from the lens surface than the meniscus one.

2. A convex-concave meniscus lens was de-signed having a high order aspheric surfaces. In spite of certain amount of deviation of the fundus image, it was possible to attain greater resolution power, lesser reflex or flare than the hitherto customary Hruby lens.