Patent ID: 7564504

Claim:
A phase plate, comprising: a polymer liquid crystal film held between transparent substrates, wherein the polymer liquid crystal film is parted spatially in the region, into which an incident light of wavelength λ enters, so that the light transmitting the phase plate assumes a different state of polarization depending on an aligning direction of the molecules of the polymer liquid crystal film, the phase plate comprises a transparent substrate having a surface on which a first polymer liquid crystal film whose molecules are aligned in a specified direction with respect to its surface, is formed in a first spatially parted region and another transparent substrate having a surface on which a second polymer liquid crystal film whose molecules are aligned in a specified direction different from that of the former polymer liquid crystal film with respect to its surface, is formed in a second spatially parted region, and the transparent substrates are laminated so that the region of the first polymer liquid crystal film and the region of the second polymer liquid crystal film are not overlapped with each other in plane view.