Projection lens

摘要

A first lens group U1 having a positive optical power, a second lens group U2 having a negative optical power and a third lens group U3 having a negative optical power are disposed in the order from a screen end. For focusing action, the first lens group U1 and the second lens group U2 respectively move in a same direction for different quantities, while the third lens group U3 remains fixed. The aperture ratio of projection lens as a whole is 1:1.1, the magnification of projection is in a range of -0.025 to 0.100.