Liquid crystal display device having a compensation film with a phase retardation

• Main Author: YANG HUI-WEN
• Format: Patent
• Language: English
• Published: 23.06.2009
• 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

Disclosed is a liquid crystal display device including a liquid crystal layer sandwiched between two substrates; two polarizers each provided on an outer side of respective one of the first and second substrates; and a compensation film provided between the polarizer and the substrate, wherein the retardation of the biaxial film satisfies the following formulae (1)-(3) and/or (4)-(5): 1<=R0(450)/R0(lambda0)<=1.3 (1) 1.1<=R0(650)/R0(lambda0)<=2.1 (2) 100 nm<=R0(lambda0)<=240 nm (3) 1<=R0(380)/R0(lambda0)<=2 (4) 1.2<=R0(780)/R0(lambda0)<=2.7 (5) where R0(380), R0(450), R0(650), R0(780) and R0(lambda0) represent the retardation of the biaxial film at wavelengths of 380 nm, 450 nm, 650 nm, 780 nm and lambda0, respectively, and lambda0 is the value calculated by lambda0=[ne-no]xd/k (where ne and no represent the refractive indices of the liquid crystal, d represents the cell gap defined between the two substrates, and k is a constant, 0.55<=k <=1).