Projection image display apparatus with diffractive reflection polariser and astigmatism corrector

摘要

A projection type image display apparatus comprises a reflection polarizing plate 101, 102, 103 which functions as a polarizing plate by its grating function only in a specific direction, and an astigmatism corrector 211-213 between the reflection polarising plate and a projection lens 15 for correcting astigmatism which occurs in this plate wherein image light reflected by a reflection image diaplay 111-113 enters on a working plane side (hatched) of the plate, and then reaches the projection lens after passing through the plate. Dichroic mirrors 6,7 and cross dichroic prism 14 are shown.