An optical sight includes an optical train having an optical path therethrough. The optical train typically includes an objective, a prism that receives the optical path from the objective, and an eyepiece that receives the optical path from the prism. A reticle is formed on a surface of the prism. The reticle is illuminated by a reticle illumination source including a light source having a light-source output beam that illuminates the reticle, and a light diffuser lying in the light-source output beam between the light source and the reticle. The light diffuser is made of a non-lambertian material such as acetal.