Method and apparatus for offsetting baseline portion of oximeter

Surgery – Truss – Pad

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

128664, 128666, 356 41, A61B 500, A61B 600

Patent

active

048921017

ABSTRACT:
A feedback control system is disclosed for use in processing signals employed in pulse transmittance oximetry. The signals are produced in response to light transmitted through, for example, a finger at two different wavelengths. Each signal includes a slowly varying baseline component representing the relatively fixed attenuation of light produced by bone, tissue, skin, and hair. The signals also include pulsatile components representing the attenuation produced by the changing blood volume and oxygen saturation within the finger. The signals are processed by the feedback control system before being converted by an analog-to-digital (A/D) converter (72) for subsequent analysis by a microcomputer (16). The feedback control system includes a controllable offset subtractor (66), a programmable gain amplifier (68), controllable drivers (44) for the light sources (40, 42), and the microcomputer (16). The microcomputer (16) receives signals from the offset subtractor (66), gain amplifier (68), drivers (44) and A/D converter (72) to produce signals that control the function of the subtractor (66) and drivers (44) in the following manner. Normally, the drivers ( 44) are maintained within a predetermined current range. In the event the microcomputer (16) senses an output from the converter (72) that is not within a predetermined range, the drive signal is adjusted to produce an acceptable signal. The magnitude of the offset removed by the subtractor (66), as controlled by the microcomputer (16), is maintained at a constant level when the converter (72) output is within a first predetermined range and is a predetermined function of the converter (72) output when that output falls within a second predetermined range.

REFERENCES:
patent: 2706927 (1955-04-01), Wood
patent: 3430106 (1967-02-01), McDowell
patent: 3709612 (1973-01-01), Clemens
patent: 4086915 (1978-05-01), Kofsky et al.
patent: 4167331 (1979-09-01), Nielsen
patent: 4188551 (1980-02-01), Iwasaki et al.
patent: 4586513 (1986-05-01), Hamaguri
patent: 4639134 (1987-01-01), Bletz
patent: 4759369 (1988-07-01), Taylor
patent: 4819646 (1989-04-01), Cheung et al.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Method and apparatus for offsetting baseline portion of oximeter does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method and apparatus for offsetting baseline portion of oximeter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for offsetting baseline portion of oximeter will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-140099

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.