Optical system for providing a uniform intensity distribution and optical microscope

摘要

An optical system which corrects an intensity distribution of incident light to a flat intensity distribution includes: a first lens group which includes at least one lens (2) and has a positive refracting power; a second lens group which includes at least one lens (3) and has a negative refracting power, the second lens group being positioned behind the first lens group in a direction of the incident light; and a third lens group which includes at least one lens (4) and has a positive refracting power, the third lens group being positioned behind the second lens group in the direction of the incident light. In the optical system, the intensity distribution of the incident light is corrected to the flat intensity distribution by spherical aberrations of the first lens group, the second lens group and the third lens group.
In case of an incident light having different divergence angles in X-direction and Y-direction, the optical system comprises two lens groups, each one including a cylindrical lens having positive refracting power.