POLARIZING PLATE

• Main Authors: SHODA TAKAMORI, NAKAHARA KENJI, SUGINO YOICHIRO, HAMAMOTO EIJI, KUSUMOTO SEIICHI
• Format: Patent
• Language: English
• Published: 22.06.2001
• Edition: 7
• Subjects: DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

PROBLEM TO BE SOLVED: To develop a polarizing plate such that when the plates are disposed in the cross-Nicol position, the difference in the transmittance of light between the front view and oblique view is small and that a liquid crystal display device or the like hardly causing a decrease in the contrast for the oblique view can be formed. SOLUTION: The polarizing plate consists of a polarizing film containing a dichroic substance and having >=60 dichroic ratio at 600 nm wavelength and transparent protective layers on both surfaces of the film. When the polarizing plates are disposed in a cross-Nicol position and light at 550 nm wavelength is made to enter, the transmittance T0 for the incident light perpendicular to the plate and the transmittance T40 for oblique incident light in 45 deg. direction from the polarizing axis and at 40 deg. angle from the normal line satisfy the relation of T40/T0<=72. Thus, leakage of light in the oblique viewing angle when the polarizing plates are disposed in a cross-Nicol position can be decreased.