| 摘要 |
PROBLEM TO BE SOLVED: To reconcile the effect peculiar to cholesteric liquid crystal with the diffraction effect resulting from the area showing diffractive performance to provide an excellent visibility and design property by constituting a diffracting element from a cholesteric liquid crystal layer partially having the area showing diffractive performance, and setting the actual film thickness of the cholesteric liquid crystal layer in a specified range. SOLUTION: This polarizing diffraction element is formed of at least a cholesteric liquid crystal layer partially having the area showing diffractive performance. The actual film thickness of the cholesteric liquid crystal layer constituting this polarization diffracting element is set to 0.6-6 μm, preferably 0.7-5 μm, more preferably, 0.8-4 μm. When the actual film thickness of the cholesteric liquid crystal layer is less than 0.6 μm, the selective reflecting characteristic and the circular polarization characteristic by cholesteric alignment might be deteriorated. When the thickness exceeds 6 μm, the selective reflecting characteristic and the circular polarization characteristic by cholesteric alignment might appear too conspicuously. |
