Patent ID: 11860361
Assignee: FUJIFILM CORPORATION
Field: Optics (Instruments)
Classification: CPC G  B | IPC B  G

Claim 0:
1. A reflection film comprising:
a linearly polarized light reflection layer obtained by laminating optically anisotropic layers and isotropic layers; and
a polarization converting layer,
wherein the polarization converting layer satisfies any of conditions below,
(A) the polarization converting layer is a retardation layer in which a front retardation at a wavelength of 550 nm is 30 nm to 200 nm and an angle between a slow axis direction and a direction of a transmission axis of the linearly polarized light reflection layer is 35° or less, and
(B) the polarization converting layer is a layer in which a helical alignment structure of a liquid crystal compound is fixed, and a number of pitches x in the helical alignment structure and a film thickness y (unit μm) of the polarization converting layer satisfy all relational expressions below,

0.1≤x≤1.0  (i)

0.5≤y≤3.0  (ii)

3000≤(1560×y)/x≤50000  (iii)