CATADIOPTRIC OPTICAL SYSTEM WITH MULTI-REFLECTION ELEMENT FOR HIGH NUMERICAL APERTURE IMAGING

摘要

A catadioptric system includes a first catadioptric group, a second catadioptric group, and a lens group disposed in axial alignment with each other. The first catadioptric group includes a solid lens having an input surface, a primary reflective surface, secondary reflective surface and an exit surface. The primary reflective surface is a curved surface concave towards the secondary reflective surface. A light flux entering through the input surface undergoes more than two reflections between the primary and secondary reflective surfaces, prior to exiting through the exit surface. At least one of the primary reflective surface and secondary reflective surface has a continuous and smooth topological profile.

主权项

1. A catadioptric optical system comprising, in order from an object side to an image side:
a first catadioptric group; a second catadioptric group disposed in axial alignment with the first catadioptric group; and a lens group disposed in axial alignment with the first and second catadioptric optical groups, the first catadioptric group comprising: an object-side surface having an input surface centered on the optical axis; an image-side surface having an exit surface also centered on the optical axis; a primary reflective surface formed on the image-side surface in a rotationally symmetric zone around the exit surface; a secondary reflective surface formed on the object-side surface in a rotationally symmetric zone around the input surface; wherein the primary reflective surface is a curved surface concave towards the secondary reflective surface, wherein the input surface is configured to transmit an incident light flux therethrough, and the primary reflective surface is configured to reflect the light flux towards the secondary reflective surface, and wherein the light flux entering through the input surface undergoes more than two reflections between the primary reflective surface and the secondary reflective surface, prior to exiting through the exit surface.