Patent ID: 9638906
Date: 2017-05-02
CPC Classifications: G02B,G03F

Claim:
1. A projection optical system configured to form an image on a substrate and including a catadioptric illumination relay lens, a catadioptric projection lens, and a spatial light modulator (SLM) positioned to receive light from the catadioptric illumination relay lens and reflect said light towards the catadioptric projection lens, wherein the catadioptric projection lens includes first and second portions in optical communication with one another, said second portion configured as a catadioptric optical system forming, in light received from the catadioptric illumination relay lens, an intermediate optical image at a location between elements of the second portion; said first portion located between the second portion and an image plane of the projection optical system, said first portion configured as a dioptric optical system disposed to transfer light from said location to the image plane of the projection optical system to form said image at the image plane of the projection optical system, said catadioptric projection lens configured to satisfy a condition of |β