PRODUCTION OF PHASE DIFFERENCE FILM

• Main Authors: SAKAKURA KAZUAKI, MIZUGUCHI KEIICHI, SHIMOMURA HIDEKI
• Format: Patent
• Language: English
• Published: 29.08.1995
• Edition: 6
• 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

PURPOSE:To obtain a process for production which is easily dealable with a change of retardation and is efficient by sticking heat shrinkable films to a uniaxially stretched thermoplastic resin film and thermally shrinking these films. CONSTITUTION:The heat shrinkable films are stuck to one or both surfaces of the uniaxially stretched thermoplastic resin film and are heated in such a manner that the axial direction of the thermal shrinkage of these heat shrinkable films intersects orthogonally with the stretching axial direction of the uniaxially stretched thermoplastic resin film. The uniaxially stretched thermoplastic resin film, then, shrinks in the stretching axial direction and shrinks in the direction orthogonal with the stretching axial direction or its expansion is suppressed. The retardation ratio R40/R0 and/or retardation value of the uniaxially stretched thermoplastic resin film is thus changed. Where R40 denotes the retardation measured in the state of inclining the phase film at 40 deg. from horizontal and R0 denotes the retardation measured in the state of not inclining the film.