The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 17, 1987
Filed:
Apr. 19, 1985
Eltro GmbH, Heidelberg, DE;
Abstract
A method and circuit arrangement for performing surface measurements to enable a beam source to be triggered such that changes in the oscillation frequency, maximum scanning angle, and distance from the measurement surface of the scanner are automatically compensated for. In one embodiment an alternating voltage proportional to the lateral displacement of the impinging beam from a reference point is generated and then compared with a stepped reference voltage. A trigger signal is produced when the alternating voltage equals the reference voltage, so that the beam impinges at equidistant intervals. The reference voltage is adjusted to compensate for changes in distance and maximum scanning angle. In another embodiment, a pulse sequence is generated such that the number of pulses occurring in the scanning cycle is constant. The pulses are counted and the count is compared with reference values corresponding to equiangular intervals. A trigger signal is output if the count equals the reference value.