Abstract
A digital indicating null method vibrating probe electrometer for electrophotography has been developed. Nulification is made automatically by the aid of the servo techniques. Compensating voltage is supplied from electronically stabilized voltage source, so that high accuracy and high stability of about ±0.2%, on potential measurement is attained.
A coded disk analogue to digital converter connected with nullifying potentiometer encodes the angle of rotation to three decimal numbers and indicates the surface potential of the electrophotographic materials in digital numbers in the range of 0 to-999 volts.
The exposure lamp is 50 watt exciter lamp, its color temperature is adjusted at 2854°K and maximum intensity obtainable is about 500 lux. The exposure intensity is controlled with an optical neutral filter.
The sector type of electromagnetic shutter controlled by a crystal controlled digital timer gives accurate exposure.
