Patent · US Expired

Process for the photo-optical measurement of the absorption behavior of solid, liquid and gaseous media

US4155010A · kind A · utility

1Cited by

3References

6Claims

0Family size

Assignee

Leybold-Heraeus GmbH & Co. KG · DE

Inventors

Gunther Schunck · Bruchköbel, DE
Albert Randow · Bruchköbel, DE

Key dates

Filing date	Feb 28, 1977
Grant date	May 15, 1979
Priority date	—
Expiry date	Feb 28, 1997

Classification

Technology area (CPC G)Physics
CPC primaryG01J1/36
WIPO fieldMeasurement
WIPO sectorInstruments

Abstract

Process for the photo-optical measurement of the absorption behavior of solid, liquid and gaseous media. A measurement light beam from an optical radiation source is made intermittent by a rotating chopper comprising a rotatable metal wheel. The chopper frequency is maintained constant by regulation of the speed of the metal wheel by two alternating-current magnets inducing eddy currents to slow or speed up the wheel. The actual speed of the wheel is detected and compared with a reference speed and the magnitude of the excitation currents is adjusted on the basis of the rotatory speed difference to effect the regulation of the speed of the chopper.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.