Catadioptric optical system with total internal reflection for high numerical aperture imaging

摘要

A catadioptric optical system includes, in order from an object side to an image side and arranged along an optical axis, a first catadioptric unit, a second catadioptric unit disposed in axial alignment with the first catadioptric unit and with a space therebetween; and a lens group disposed in axial alignment with the first and second catadioptric optical units. Light rays arriving from an object plane undergo a first reflection at the image-side surface of the first catadioptric optical unit, a second reflection at the object-side surface of the first catadioptric optical unit, a third reflection at the image-side surface of the second catadioptric optical unit, and a fourth reflection at the object-side surface of the second catadioptric optical unit. Advantageously, the sum the outward Petzval curvatures is cancelled out by the sum of inward Petzval curvatures.

主权项

1. A catadioptric optical system comprising, in order from an object side along an optical axis:
a first catadioptric unit; a second catadioptric unit disposed so as to have a space from the first catadioptric unit; and a lens group, wherein the first catadioptric unit includes a first object-side surface having a concave specularly reflective portion, and a first image-side surface having a first transmissive portion and a total internal reflection portion surrounding the first transmissive portion, wherein the second catadioptric unit includes a second object-side surface having a convex specularly reflective portion and a second image-side surface having a concave specularly reflective portion, and wherein light rays from an object are sequentially reflected by the first image-side surface, the first object-side surface, the second image-side surface, and the second object-side surface.