Constituent concentration measuring apparatus and constituent concentration measuring apparatus controlling method
US8332006B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 2, 2005 |
| Grant date | Dec 11, 2012 |
| Priority date | — |
| Expiry date | Mar 2, 2030 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/1495
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An object of the present invention is to provide a noninvasive constituent concentration measuring apparatus and constituent concentration measuring apparatus controlling method, in which accurate measurement can be performed by superimposing two photoacoustic signals having the same frequency and reverse phases to nullify the effect from the other constituent occupying large part of the object to be measured. The constituent concentration measuring apparatus according to the invention includes light generating means for generating two light beams having different wavelengths, modulation means for electrically intensity-modulating each of the two light beams having different wavelengths using signals having the same frequency and reverse phases, light outgoing means for outputting the two intensity-modulated light beams having different wavelengths toward a test subject, and acoustic wave detection means for detecting an acoustic wave generated in the test subject by the outputted light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.