Patent ID: 9122068
Filing Date: 2015-09-01
Classification: G02B,G03B,H04N

Abstract:
1. A polarization converting element group for a projection apparatus, comprising: a polarization beam splitter, having a plurality of polarization plated films, wherein each of the polarization plated films includes an angle with a surface of the polarization beam splitter to divide a light beam into a first polarized light beam with a first polarization direction and a second polarized light beam with a second polarization direction; and a plurality of half wave plates, disposed next to the polarization beam splitter and moving in a reciprocating motion with respect to the polarization beam splitter; wherein at a first time point, each of the half wave plates moves to a first position to face one of the polarization plated films to allow the second polarized light beam to pass therethrough and turn into the second polarized light beam with the first polarization direction; and at a second time point, each of the half wave plates moves to a second position to face another one of the polarization plated films to allow the first polarized light beam to pass therethrough and turn into the first polarized light beam with the second polarization direction.