(19)

(11)

EP 0 267 256 A1

(12)

(43) Date of publication: 18.05.1988 Bulletin 1988/20 (21) Application number: 87903362.0 (22) Date of filing: 20.05.1987

(51) International Patent Classification (IPC):  G01R 15/ 24( . ) G02F 1/ 095( . ) G01R 33/ 032( . ) (86) International application number: PCT/GB1987/000345 (87) International publication number: WO 1987/007387 (03.12.1987 Gazette 1987/27)

(84) Designated Contracting States: CH DE FR LI (30) Priority: 20.05.1986 GB 19860012190 (71) Applicants: Qian, Jingren Hefei, Anhui (CN) LI, Luksun GB-Southampton, Hampshire (GB) Payne, David Neil Winchester, Hampshire, (GB)	(72) Inventors: Qian, Jingren Hefei, Anhui (CN) LI, Luksun GB-Southampton, Hampshire (GB) Payne, David Neil Winchester, Hampshire, (GB) (74) Representative: Cullis, Roger  Patents Department British Technology Group Ltd 101 Newington Causeway London SE1 6BU London SE1 6BU (GB)