LIQUID CRYSTAL OPTICAL SWITCH

• Main Author: KASAHARA KUMIO
• Format: Patent
• Language: English
• Published: 19.11.1986
• 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 compensate the temperature dependency of the double refraction of liquid crystal by that of the thickness of a liquid crystal layer and to reduce the temperature dependency of crosstalk by opening the one end surface of a liquid crystal cell from a substrate in space. CONSTITUTION:A rectangular prism 18 fitted to one end surface of the liquid crytal cell 17 can be moved independently of the substrate 19, so that when the cell 17 sealed with d=2.8mum thickness at 20 deg. peripheral temperature is raised up to 50 deg. peripheral temperature, the change of the thickness becomes 5X10<-2>, increasing 5% thickness. On the other hand, the double refraction of the liquid crystal are 0.121 and 0.115 at 20 deg. and 50 deg. peripheral temperatures respectively, reducing 5% double refraction. Therefore, the increase of the depth (d) and the reduction of double refraction are offset each other, so that the temperature dependency of double refraction of the liquid crystal is removed and the increase of crosstalk due to the temperature change can be reduced.