Optical element, illuminating device, and projection type video display

摘要

An optical element includes a dichroic surface formed by a multilayer dielectric film or the like and a polarized beam splitter surface formed by a multilayer dielectric film or the like. The dichroic surface transmits light (G and R) from a green wavelength band to a red wavelength band irrespective of the polarization directions of light, and reflects light (B) in a blue wavelength band. The polarized beam splitter surface reflects an S-polarized light (Gs) in a green wavelength band. Furthermore, the polarized beam splitter surface transmits an S-polarized light (Bs) and a P-polarized light (Bp) in the blue wavelength band, and also transmits the S-polarized light (Rs) and P-polarized light (Rp) in the red wavelength band.