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. 13, 1996
Filed:
Dec. 02, 1994
Tsuneyuki Urakami, Hamamatsu, JP;
Yutaka Tsuchiya, Hamamatsu, JP;
Hamamatsu Photonics K.K., Hamamatsu, JP;
Abstract
Light the intensity of which is modulated to the initial intensity by a modulating signal having an ac component with a predetermined frequency and which is from the intensity tuneable light irradiating unit irradiates the scattering and absorption medium which is an object to be measured. The modulated light incident on the scattering and absorption medium propagates in the scattering and absorption medium, emerges therefrom and is incident to the photodetecting unit, and the photodetecting unit converts the incident light into an electric signal corresponding to the intensity of the incident light, and thereafter, outputs the electric signal as an optically detected signal. The feedback unit extracts the ac component from the input optically detected signal, and the intensity of the ac electric signal and the adjusting value are compared and the variation of the quantity of generating light is sent to the intensity tuneable light irradiating unit. Then, the phase difference detection is performed as the gain of the photodetecting means is fixed and the intensity of the ac component having a modulation frequency emitted from the photodetecting means is maintained so as to substantially match with the preset adjusting value.