| 摘要 |
<P>PROBLEM TO BE SOLVED: To realize a structure of a polarization conversion element in which an ultraviolet curable resin adhesive is used that is excellent in heat-resistance and light-resistance performance, and wave plates are included that reliably function as 1/2 wave plates for light beams having a plurality of wavelength bands. <P>SOLUTION: A polarization conversion element includes an optical element that has a plurality of translucent substrates, and polarization separation films and reflection films which are alternately provided between the translucent substrates; and wave plates that are arranged on a light emission surface of the optical element and rotate a polarization plane of light emitted from the optical element by θ. In the polarization conversion element, the thickness of adhesion layers bonding the translucent substrates is 5 μm or more and 10 μm or less, each wave plate has a first wave plate with a phase difference of Γ1, a second wave plate with a phase difference of Γ2, a third wave plate with a phase difference of Γ3, with respect to a light of design wavelength λ included in any of a plurality of wavelength bands, the first to third wave plates are laminated so that optical axis azimuths thereof θ1 to θ3 intersect, and the following expressions are satisfied: Γ1=180+360×n (deg), Γ2=180+360×n (deg), Γ3=180+360×n (deg), θ1=15±5, θ2=45±5, and θ3=75±5. <P>COPYRIGHT: (C)2013,JPO&INPIT |
