SU1467521A1 - Device for measuring the intensity of electrostatic field - Google Patents

Abstract

This invention relates to electrical measurements. The purpose of the invention is to simplify the device and increase the measurement accuracy. The device contains an electro-optical cell 1, consisting of transparent electrodes 2, the space between which is filled with a layer of nematic liquid crystal 3 with negative dielectric constant anisotropy, the thickness of which is specified by an insulating gasket 4, as well as conductive plates 5, LED 6, photodetector 7, switch 8, power supply 9 and recording unit Sh. By placing plates 5 connected to electrodes 2 into an electric field, the transparency of cell 1 can be changed depending on the magnitude of the voltage lektromagnitnogo floor. Improving the accuracy of measurements is provided by the almost complete isolation between the plates 5 and the inputs of the recording unit 10 without the use of complex electronic: circuits. 1 il. i (L

Description

The invention relates to electrical engineering and can be used to measure the strength of static and quasistatic electric fields.

The purpose of the invention g 'simplification of the device, and increase accuracy.

The drawing shows a structural electrical diagram of a device for measuring electrostatic field strength.

The device for measuring the electrostatic field strength contains an electro-optical cell 1, including 15 first and second transparent electrodes 2, the space between which is filled with a layer of nematic liquid crystal 3 with negative dielectric constant anisotropy, the thickness of which is specified by an insulating gasket 4. To each of the first and second the transparent electrode 2 is connected to the first and

I _ the second parallel conductive plate 5, respectively, the light source is an LED 6, a photodetector 7, a switch 8, a power source 9, a recording unit 10.

The device operates as follows.

Plate 5, parallel to one another at a given size. standing, they are placed in an electric field perpendicular to the field lines of 35 fields. In the presence of an electrostatic field through the plates 5, a sufficient voltage is generated on the liquid crystal electro-optical cell 1 to excite the nematic liquid-crystal 40. In this case, the liquid-crystal electro-optical cell 1 passes from a transparent state to an opaque one due to dynamic light scattering. Therefore, the intensity of the light emitted by the LED 6, passing through the liquid crystal electro-optical cell 1, decreases, which is recorded using the photodetector 7 and the registration unit 10 59. Moreover, depending on the magnitude of the electrostatic field, the transmission of the liquid crystal electro-optical cell 1 and, accordingly, the magnitude of the recorded electrostatic field changes. At small values of the field strength, the scattering is insignificant, with increasing field strength, the liquid crystal electro-optical cell 1 becomes scattering and more opaque for light passing through the liquid-crystal electro-optical cell 1. .

Thus, by placing the plates 5 in an electric field, it is possible to change the transparency of the liquid crystal electro-optical cell 1 depending on the magnitude of the electromagnetic field strength 20.

. Improving the accuracy of measurements is ensured by almost complete isolation between the plates 5 and the inputs of the registration unit 10 without the use of complex electronic circuits.

The upper cutoff frequency of the measured electric field is ~ 1 kHz, which is due to the absence of dynamic scattering at frequencies above 1 kHz. ' thirty

Claims (1)

Claim. A device for measuring the electrostatic field strength, containing a field sensor made in the form of first and second parallel conductive plates, a registration unit, characterized in that, in order to simplify the device and improve accuracy, an electro-optical cell filled with a nematic liquid crystal with negative anisotropy of dielectric constant is introduced , to the first and second transparent electrodes of which the first and second parallel conductive plates are attached, respectively, an LED and a photodetector nick, located on opposite sides of the electrooptic cell on the same axis with it, and the photodetector output is connected k.vhodu registration unit.