Circuit for defining the dye dilution curves in vivo and in vitro for calculating the cardiac blood flowrate value per minute
US4095117A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 30, 1974 |
| Grant date | Jun 13, 1978 |
| Priority date | — |
| Expiry date | Jun 30, 1994 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/0275
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
The invention concerns a circuit for the determination of the concentration of any component of a liquid containing three different components having different optical properties, for the determination of the concentration sum of all components and of one other component, for the determination of the product and of the quotient which is formed by the third component, and for the calculation of the blood volume per minute of the heart. One or more light sources, a light sensing element, an optical filter and a lens are disposed in the circuit, and also power supply circuits and control circuits. To these are added a signal converting unit or a sensing system operating on three wavelengths other than the isobestic points or on a range containing these points, containing optical measurement channels, and measuring on the transmission or reflection principle. The signals delivered by the three-channel sensor or by the signal converter, as the case may be, are processed by logarithmatic circuits. The logarithmating circuits are connected to channel amplifiers, and to the latter are connected subtraction circuits and multiplication circuits. By means of the electronics of suitable constr…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.