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:
Jan. 06, 2015
Filed:
Feb. 02, 2012
Tatsuya Ueno, Tokyo, JP;
Tatsuya Ueno, Tokyo, JP;
Azbil Corporation, Tokyo, JP;
Abstract
A velocity measuring device emitting a laser beam at a web; a photodiode converting an optical output of the laser into an electric signal; a laser driver operating the laser to alternate a first emitting interval wherein the oscillating wavelength increases and a second emitting interval wherein the oscillating wavelength decreases; a current-voltage converting/amplifying portion converting the electric current from the photodiode into a voltage; a filter portion removing a carrier wave from the output of the current-voltage converting/amplifying portion; a signal extracting portion calculating a number of interference waveforms in the output of the filter portion; and a calculator calculating the velocity of the web based on the result of the extracting portion. The laser driver operates so the absolute values for the rates of change, in respect to time, of the oscillating wavelengths during the first emitting interval and during the second emitting interval are different.