Liquid crystal electrostatic voltmeter

Details Liquid crystal electrostatic voltmeter Liquid crystal electrostatic voltmeter

1986-12-18

1988-11-22

Eisenzopf, Reinhard J.

Electricity: measuring and testing

Measuring, testing, or sensing electricity, per se

Using radiant energy

324 73R, 324158R, 350356, G01R 2316, G02F 103

Patent

active

047868589

ABSTRACT:
A voltage sensing device having a liquid crystal cell electrically connected to a charged surface and having a light transmissivity varying with applied voltage. A light source is directed through the liquid crystal cell, and a light detector, detects changes in the intensity of light directed through the cell and providing an output indicative of variations in voltage on the charged surface. Polarizers, which polarize light from the light source directed through the liquid crystal cell, and analyze light exiting the cell, convert electro-optically induced phase changes into intensity changes. A saturation level biasing voltage is periodically applied to the liquid crystal cell to set the cell to a reference level, clearing the cell of transient polarization effects. A second reference liquid crystal cell may be provided, electrically coupled to a reference voltage. Signals from the charged surface derived by the liquid crystal cell connected to the surface are compared with reference signals derived by the reference cell prior to output of the signal to eliminate a time-based drift component from the output.

REFERENCES:
patent: 3627408 (1971-12-01), Fergason
patent: 3934199 (1976-01-01), Channin
patent: 3936815 (1976-02-01), Kogure et al.
patent: 3938878 (1976-02-01), Fox
patent: 3939412 (1976-02-01), Hermstein et al.
patent: 4029393 (1977-06-01), Dungan et al.
patent: 4100484 (1978-07-01), Buchheit
patent: 4112361 (1978-09-01), Nakada et al.
patent: 4277146 (1981-07-01), Morgan et al.
patent: 4279474 (1981-07-01), Belgorod
patent: 4396997 (1983-08-01), Kahn et al.
patent: 4423927 (1984-01-01), Bly
patent: 4446425 (1984-05-01), Valdmanis et al.
patent: 4465969 (1988-08-01), Tada et al.
patent: 4579422 (1986-04-01), Simoni et al.
patent: 4589735 (1986-05-01), Saunders
patent: 4643525 (1987-02-01), Haim
Xerox Disclosure Journal, vol. 2, No. 6, Nov./Dec., 1977, p. 91 "Liquid Crystal Electrometer", R. Case.
Molecular Crystals and Liquid Crystals", A New Type of Analog Voltmeter Using Electrooptic Effect in Nematic Liquid Crystals", vol. 38, No. 4, 1977, pp. 303-309.
Review of Scientific Instruments, "Direct Reading DC Electro-Optic Voltmeter with High Input Resistance", K. Geisen et al., vol. 48, No. 7, Jul. 1977, pp. 790-792, American Institute of Physics, NY.
Proceedings of the Society for Information Display, "A Facsimile Printer Utilizing an Array of Liquid Crystal Cells", J. Tults, vol. 12, No. 4, Fourth Quarter 1971, pp. 199-203, Los Angeles, CA.

Affiliated with

Also associated with

Rating

Liquid crystal electrostatic voltmeter does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Liquid crystal electrostatic voltmeter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Liquid crystal electrostatic voltmeter will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-437114