Projection system for video images using laser as light source, incorporates convex or concave mirror directing reflected light beam onto flat screen

摘要

A parallel laser light beam (1) may strike a convex cylindrical mirror (2), at an angle of approximately 45 degrees. The reflected beam is defocused and spreads at an angle (Theta 1 + Theta 2), where the total angle Theta tot = Theta 1 + Theta 2 = 2 x (alpha 2 + alpha 1). alpha 1 and alpha 2 are 90 degrees minus the angles of incidence of the edges of the beam on the mirror.