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:
Oct. 02, 2012
Filed:
Jun. 08, 2009
Tomoyu Yamashita, Miyagi, JP;
Motoki Imamura, Miyagi, JP;
Tomoyu Yamashita, Miyagi, JP;
Motoki Imamura, Miyagi, JP;
Advantest Corporation, Tokyo, JP;
Abstract
An object is to enable a change in a frequency for which an electric signal based on an optical signal is measured by a spectrum analyzer. An optical measurement device includes a first photoconductive switch that receives predetermined pulse light from a first laser light source, and outputs terahertz light having the same repetition frequency as the repetition frequency of the predetermined pulse light. The optical measurement device also includes a second photoconductive switch that receives the terahertz light and a sampling light pulse, and outputs a signal corresponding to a power of the terahertz light at a time point when the sampling light pulse is received. The optical measurement device further includes an RF spectrum analyzer that measures a magnitude of the signal corresponding to a measured frequency that changes over time, an optical coupler that outputs a simultaneous light pulse when the predetermined pulse light and the sampling light pulse are simultaneously input, a photo detector that converts the simultaneous light pulse into an electric signal as a trigger signal, and an optical delay circuit that delays the trigger signal.