Hyper numerical aperture imaging lens using a thin multi reflection Catadioptric optical element

Several state-of-the-art imaging applications require a large operational spectral band, a large field size, and a high numerical aperture (NA). The design of a lens that simultaneously meets these requirements is a challenging task. We present optical designs of hyper NA imaging systems that comprise a multi reflection optical element. Light entering this element reflects multiple times before exiting. The present lens designs are 1.65 NA imaging system that operate in the broad spectral band [486.1 ∼656.3 nm], have field size of 1.75 mm, and 20X magnification.