Pulse oximeter having a low power led drive
US6226539A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 26, 1999 |
| Grant date | May 1, 2001 |
| Priority date | — |
| Expiry date | May 26, 2019 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B2560/0209
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A photometer (10) includes a light source (12) operable to direct light toward a sample (14), a detection circuit (16) operable to detect the light after it has passed through the sample, and a drive circuit (18) for powering the light source. The drive circuit includes an input (20) for coupling with a source of power and energy storage circuitry (22) coupled with the input. The energy storage circuitry is operable to store energy from the source of power when switched to a charging state and to deliver current to the light source in a ramped manner when switched to a discharge state so that the current peaks at a selected time. The drive circuit delivers a controlled amount of current to the light source that peaks only after the detection circuit has settled so that power is not wasted at the startup of the oximeter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.