Design of compact freeform off-axis TMA system

Aiming at the design requirement of miniature reflective optical system,a new type of off-axis three-mirror anastigmat (TMA) and freeform surface are adopted, the F#1.8,and diagonal field of view7.5° is realized.Light overlap many times within the optical system,the full field average RMS Wavefront abberations is 0.017λ(λ=10μm). Compared with other optical system, the new freeform TMA has small size, high transmittance, large field of view, large relative aperture, no centered obscuration, low stray, radiation, wide spectral band, etc.