Apparatus for determining the concentration of light-absorbing materials in blood
US5766125A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 27, 1995 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | Apr 27, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/3151
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Light beams of different wavelengths, emitted from a light generating device, are transmitted through a living tissue. The transmitted light beams are converted into electrical signals by a photoelectric transducing device. A pulsation calculating device calculates a pulsation of an absorbance of tissue of a living tissue for each wavelength on the basis of the output signal of the photoelectric transducing device. By using this, a pulsation ratio calculating device calculates the ratio of the pulsations of the absorbance values. A concentration calculating device puts the output signal of the pulsation ratio calculating device into a formula having a single unknown on the tissue term, which is constructed on the basis of the fact that a predetermined relation is present between the tissue terms of the respective wavelengths, thereby calculating a value of the tissue term and the concentration of light absorbing material in blood.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.