Blood diagnostic spectrophotometer
US4357105A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 6, 1980 |
| Grant date | Nov 2, 1982 |
| Priority date | — |
| Expiry date | Aug 6, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/0692
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A compact, portable, clinical instrument dedicated to hemoglobin determination employs an L.E.D. light source with a peak output wavelength of about 553 nanometers and a yellow-blocking filter with a long wavelength cut-off not longer than about 565 nanometers. Thus, the relative amount of energy incident upon the blood sample in the 540 nm. hemoglobin absorption band is maximized. In addition to the L.E.D., the photodetector and the amplifying, inverting, log conversion, digital conversion, display and power supply regulation circuits are also exclusively solid-state. The display is of the reflective or liquid crystal type, and the power supply regulator is a sophisticated integrated circuit containing the equivalent of many discrete components. As a result, current consumption is minimized, and battery life and instrument accuracy are maximized. As an alternative illumination source, an infra-red L.E.D. can be employed, and the instrument is then capable of blood turbidity measurement. In either case, the L.E.D. illumination source is powered by a constant-current regulator, which minimizes errors due to fluctuations in illumination intensity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.