Compensator for liquid crystal display, having two types of layers with different refractive indices alternating
Monolithic optical compensation device for improved viewing angle in liquid crystal displays
Laminated wavelength plate, circular polarizing plate and liquid crystal display
Optical device with a dichroic polarizer and a multilayer optical film Patent #: 6307676
ApplicationNo. 667222 filed on 09/21/2000
US Classes:349/117, Compensator or retarder (i.e., not using liquid crystal cell)359/494, By birefringent element359/497, Using plural elements359/499Using compensation techniques
ExaminersPrimary: Dudek, James A.
Attorney, Agent or Firm
International ClassG02F 001/133.5
Foreign Application Priority Data1999-09-22 JP
AbstractA phase retarder comprises two optically anisotropic layers A & B. The optically anisotropic layer A essentially gives the phase retardation of π at wavelength of 550 nm, and the optically anisotropic layer B essentially gives the phase retardation of π/2 at wavelength of 550 nm. The layers A and B are laminated so that the retarder has such an optical characteristic that a retardation value per wavelength is within the range of 0.2 to 0.3 at each wavelength of 450 nm, 550 nm and 650 nm. The total thickness of the layers A and B is within the range of 500 nm to 20 μm.