Off-axial three-mirror system

摘要

An off-axial three-mirror system includes a primary mirror, a secondary mirror, a tertiary mirror, and an image sensor. The secondary mirror is located on a reflective optical path of the primary mirror. The tertiary mirror is located on a reflective optical path of the secondary mirror. The image sensor is located on a reflecting optical path of the tertiary mirror. The primary mirror and the tertiary mirror are formed as one piece. The surface type of both the primary mirror and the tertiary mirror is a freeform surface.

主权项

1. An off-axial three-mirror system comprising: a primary mirror, a secondary mirror, a tertiary mirror, and an image sensor; wherein the secondary mirror is located on a primary mirror reflective optical path, the tertiary mirror is located on a secondary mirror reflective optical path, the image sensor is located on a tertiary mirror reflecting optical path; the primary mirror and the tertiary mirror are formed as one piece; and a surface type of both the primary mirror and the tertiary mirror is a freeform surface, wherein the primary mirror, the secondary mirror, and the tertiary mirror are concave minors; the surface type of both the primary mirror and the tertiary mirror is a XY polynomial surface, and an equation of the XY polynomial surface isz=x2+y2R⁡(1+1-(1+C1)⁢(x2+y2)/R2)+C2⁢x+C3⁢y+C4⁢x2+C5⁢xy+C6⁢y2+C7⁢x3+C8⁢x2⁢y+C9⁢xy2+C10⁢y3+C11⁢x4+C12⁢x3⁢y+C13⁢x2⁢y2+C14⁢xy3+C15⁢y4,R in the equation represents radius of the primary mirror and the tertiary mirror, and C1˜C15 represent coefficients in the equation.