Medical diagnostic instrument using light-to-frequency converter
US6011985A · kind A · utility
294Cited by
34References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 18, 1996 |
| Grant date | Jan 4, 2000 |
| Priority date | — |
| Expiry date | Nov 18, 2016 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/726
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A diagnostic instrument for determining a cardiovascular system parameter. In one embodiment, the instrument takes the form of a portable pulse oximeter comprising a light to frequency converter (LFC) as a sensor. Also provided is a light to frequency converter comprising a photoresistor and capacitor in circuit communication with an inverting Schmitt trigger and configured such that the inverter generates a periodic electrical signal corresponding to the amount of electromagnetic radiation illuminating the photoresistor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.