Processing

Please wait...

Settings

Settings

Goto Application

1. WO1990014606 - OPTICAL SWITCHES USING CHOLESTERIC OR CHIRAL NEMATIC LIQUID CRYSTALS

Publication Number WO/1990/014606
Publication Date 29.11.1990
International Application No. PCT/US1990/002369
International Filing Date 03.05.1990
Chapter 2 Demand Filed 24.08.1990
IPC
G02B 5/30 2006.01
GPHYSICS
02OPTICS
BOPTICAL ELEMENTS, SYSTEMS, OR APPARATUS
5Optical elements other than lenses
30Polarising elements
G02F 1/1333 2006.01
GPHYSICS
02OPTICS
FDEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH IS MODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THE DEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY, COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g. SWITCHING, GATING, MODULATING OR DEMODULATING; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
1Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
01for the control of the intensity, phase, polarisation or colour
13based on liquid crystals, e.g. single liquid crystal display cells
133Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
1333Constructional arrangements
G02F 1/31 2006.01
GPHYSICS
02OPTICS
FDEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH IS MODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THE DEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY, COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g. SWITCHING, GATING, MODULATING OR DEMODULATING; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
1Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
29for the control of the position or the direction of light beams, i.e. deflection
31Digital deflection devices
CPC
G02B 5/3016
GPHYSICS
02OPTICS
BOPTICAL ELEMENTS, SYSTEMS, OR APPARATUS
5Optical elements other than lenses
30Polarising elements
3016involving passive liquid crystal elements
G02F 1/1326
GPHYSICS
02OPTICS
FDEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH IS MODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THE DEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY, COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g. SWITCHING, GATING, MODULATING OR DEMODULATING; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
1Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating, or modulating; Non-linear optics
01for the control of the intensity, phase, polarisation or colour 
13based on liquid crystals, e.g. single liquid crystal display cells
1326Liquid crystal optical waveguides or liquid crystal cells specially adapted for gating or modulating between optical waveguides
G02F 1/31
GPHYSICS
02OPTICS
FDEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH IS MODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THE DEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY, COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g. SWITCHING, GATING, MODULATING OR DEMODULATING; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
1Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating, or modulating; Non-linear optics
29for the control of the position or the direction of light beams, i.e. deflection
31Digital deflection, ; i.e. optical switching
Y10S 359/90
YSECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
10TECHNICAL SUBJECTS COVERED BY FORMER USPC
STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
359Optical: systems and elements
90Methods
Applicants
  • CORNELL RESEARCH FOUNDATION, INC. [US]/[US]
  • E.I. DU PONT DE NEMOURS AND COMPANY [US]/[US]
Inventors
  • SHANKAR, Narendra, K.
  • MORRIS, Jeffrey, A.
  • POLLOCK, Clifford, R.
  • YAKYMYSHYN, Christopher, P.
  • WHITEHEAD, Wilson, T.
Agents
  • BLAKE, William, A.
Priority Data
354,30419.05.1989US
Publication Language English (EN)
Filing Language English (EN)
Designated States
Title
(EN) OPTICAL SWITCHES USING CHOLESTERIC OR CHIRAL NEMATIC LIQUID CRYSTALS
(FR) COMMUTATEURS OPTIQUES UTILISANT DES CRISTAUX LIQUIDES NEMATIQUES CHOLESTERIQUES OU CHIRAUX
Abstract
(EN)
Fiber optic switches (10) using layers of cholesteric or chiral nematic liquid crystals (CLCs) are disclosed. The CLC layer (12) acts both as a polarization beamsplitter and as a reflector by decomposing incoming unpolarized light into two orthogonal circularly polarized components. In a number of embodiments, switchable waveplates (14, 16) are employed to switch the polarization direction of each of the polarization components. The components are then reflected back toward the CLC layer (12) where they are recombined into a transmitted unpolarized beam (26). The direction of transmission depends on the circular sense of the polarized components, and therefore on the state of the switchable waveplates (14, 16). In other embodiments, the CLCs are used actively by exposing them selectively to electric or magnetic fields or to heat which cause a phase change that temporarily neutralizes the circular polarization effect. In this manner, the CLCs can be used as switch elements by themselves.
(FR)
Des commutateurs à fibres optiques (10) utilisent des couches de cristaux liquides nématiques cholestériques ou chiraux (CLCs). La couche CLC (12) joue le rôle à la fois d'un diviseur de rayon de polarisation et d'un réflecteur en décomposant la lumière non polarisée entrante en deux composantes orthogonales polarisées de manière circulaire. Dans plusieurs modes de réalisation, des plaques d'ondes commutables (14, 16) sont utilisées pour commuter la direction de polarisation de chacune des composantes de polarisation. Les composantes sont alors réfléchies vers la couche CLC (12) où elles sont recombinées en un rayon non polarisé transmis (26). La direction de transmission dépend du sens circulaire des composantes polarisées et par conséquent de l'état des plaques d'ondes commutables (14, 16). Dans d'autres modes de réalisation, les CLCs sont utilisées activement en les exposant sélectivement à des champs électriques ou magnétiques ou à la chaleur pour provoquer un changement de phase qui neutralise temporairement l'effet de polarisation circulaire. De cette manière, les CLCs peuvent être utilisées comme élément de commutation par eux-mêmes.
Also published as
Latest bibliographic data on file with the International Bureau