Patent ID: 9007685
Filing Date: 2015-04-14
Classification: G02B

Abstract:
1. A polarization separation device comprising: a first end surface on which incident light is incident; a polarization separation surface that reflects an s-polarized light component and transmits a p-polarized light component; a second end surface that is arranged to be opposed to the first end surface, converts the p-polarized light component transmitted through the polarization separation surface to the s-polarized light component, and reflects the converted light component to an optical axis direction which is the same as the incident light; a third end surface from which the s-polarized light component reflected by the polarization separation surface without transmitting through the polarization separation surface is output, a fourth end surface that is arranged to be opposed to the third end surface and from which the s-polarized light component reflected by the second end surface and the polarization separation surface is output, and an optical path length adjusting member that converts an optical path length of light transmitted through the third end surface, wherein a member from the first end surface to the polarization separation surface, a member from the polarization separation surface to the second end surface, and the optical path length adjusting member are formed by the same member, and a length of the optical path adjusting member in an optical axis direction is twice a distance from the polarization separation surface to the second end surface.