US5372135A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Blood constituent determination based on differential spectral analysis
Assignee: LOCK J PAUL
•
Filing: 1994-03-21
•
Granted: 1994-12-13
•
Expires: 2014-03-21
Abstract
Abstract The present invention relates to the determination of an analyte or multiple analytes in blood using information derived from the differential optical absorption spectra of blood. Specifically, the information is derived from the differential spectra of tissue before and immediately after the volume of blood in the tissue has been changed.
Inventors
- 👤 Yitzhak Mendelson
- 👤 Hannu Harjunmaa
- 👤 Yi Wang
- 👤 Brian D. Gross
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:32
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/145; A61B5/1455; A61B5/14532; G; G01; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/31; G01N21/314
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
185 words
A non-invasive in vivo method for obtaining a differential absorption spectrum relating to the concentration of analyte in living tissue comprising the steps of: a) illuminating the tissue with a first light beam which is varied in wavelength in a substantially continuous manner about a first wavelength over a first time period; b) detecting the wavelength varied first light beam after the beam has traversed a first blood volume of tissue containing said analyte to produce a first absorption spectrum comprising a substantially continuous plot of absorption in said first volume versus wavelength; c) changing the blood volume of tissue; d) illuminating the changed blood volume of tissue with a second light beam which is varied in wavelength in a substantially continuous manner about a second wavelength over a second time period; e) detecting the wavelength varied second light beam after the beam has traversed a second blood volume of tissue containing said analyte to produce a second absorption spectrum comprising a substantially continuous plot of absorption in said changed volume versus wavelength; f) combining the two absorption spectrums to produce a differential absorption spectrum.
Claim 2
Dependent Claim
185 words
A non-invasive in vivo method for obtaining a differential absorption spectrum relating to the concentration of analyte in living tissue comprising the steps of: a) illuminating the tissue with a first light beam which is varied in wavelength in a substantially continuous manner about a first wavelength over a first time period; b) detecting the wavelength varied first light beam after the beam has traversed a first blood volume of tissue containing said analyte to produce a first absorption spectrum comprising a substantially continuous plot of absorption in said first volume versus wavelength; c) changing the blood volume of tissue; d) illuminating the changed blood volume of tissue with a second light beam which is varied in wavelength in a substantially continuous manner about a second wavelength over a second time period; e) detecting the wavelength varied second light beam after the beam has traversed a second blood volume of tissue containing said analyte to produce a second absorption spectrum comprising a substantially continuous plot of absorption in said changed volume versus wavelength; f) combining the two absorption spectrums to produce a differential absorption spectrum.
Claim 3
Dependent Claim
15 words
The method of claim 1 including processing of the differential spectrum to determine analyte concentration.
Claim 4
Dependent Claim
10 words
The method of claim 2 wherein the analyte is glucose.
Claim 5
Dependent Claim
24 words
The method of claim 2 including detecting of the light by a photodetector and wherein the absorption spectrum is comprised of an electrical signal.
Claim 6
Dependent Claim
30 words
The method of claim 1 including varying the wavelength of at least one of said first and second light beams over a range between about 1100 nanometers and 2500 nanometers.
Claim 7
Dependent Claim
12 words
The method of claim 1 wherein the blood volume is changed electromechanically.
Claim 8
Dependent Claim
21 words
The method of claim 1 wherein the blood volume is changed by the natural blood pressure pulse of the cardiac cycle.
Claim 9
Dependent Claim
26 words
The method of claim 1 wherein the wavelength is varied in step d) over a range which is similar to the wavelength variation in step a).
Claim 10
Dependent Claim
154 words
A non-invasive method for obtaining a differential absorption spectrum relating to the concentration of analyte in living tissue comprising the steps of: a) illuminating the tissue at a first tissue site with a light beam which is varied in wavelength during a first time period; b) during a second time period changing the blood volume of the tissue at the first tissue site from a first volume to a second volume; c) detecting the light beam during the first time period after the wavelength varied beam has traversed the first volume of tissue containing said analyte to produce a first absorption spectrum; d) detecting the light beam during the second time period after the wavelength varied beam has traversed the second volume of tissue containing said analyte to produce a second absorption spectrum; e) combining the two absorption spectrum to produce a differential absorption spectrum which represents tissue absorption versus a spectrum of wavelengths.
Claim 11
Dependent Claim
154 words
A non-invasive method for obtaining a differential absorption spectrum relating to the concentration of analyte in living tissue comprising the steps of: a) illuminating the tissue at a first tissue site with a light beam which is varied in wavelength during a first time period; b) during a second time period changing the blood volume of the tissue at the first tissue site from a first volume to a second volume; c) detecting the light beam during the first time period after the wavelength varied beam has traversed the first volume of tissue containing said analyte to produce a first absorption spectrum; d) detecting the light beam during the second time period after the wavelength varied beam has traversed the second volume of tissue containing said analyte to produce a second absorption spectrum; e) combining the two absorption spectrum to produce a differential absorption spectrum which represents tissue absorption versus a spectrum of wavelengths.
Claim 12
Dependent Claim
14 words
The method of claim 9 including processing the differential spectrum to determine analyte concentration.
Claim 13
Dependent Claim
10 words
The method of claim 9 wherein the analyte is glucose.
Claim 14
Dependent Claim
167 words
Apparatus for non-invasive generation of a differential signal relating to the concentration of analyte in living tissue comprising: a) a light source generating a beam of light; b) a tuner varying the frequency of said beam of light over a predetermined time period; c) a photosensitive detector for detecting said frequency varying light after traversing said tissue: (ii) when the tissue contains a first volume of blood; and (iii) when the tissue contains a second volume of blood; to produce two separate absorption signals a first one of which is proportional to the absorption of said frequency varying light by said tissue containing the first volume of blood versus frequency and a second of which is proportional to the absorption of said frequency varying light by said tissue containing the second volume of blood versus frequency; and d) generating means for generating said differential signal which is proportional to the difference between the light detected versus frequency for each signal detected in (c) (i) and (ii) above.
Claim 15
Dependent Claim
167 words
Apparatus for non-invasive generation of a differential signal relating to the concentration of analyte in living tissue comprising: a) a light source generating a beam of light; b) a tuner varying the frequency of said beam of light over a predetermined time period; c) a photosensitive detector for detecting said frequency varying light after traversing said tissue: (ii) when the tissue contains a first volume of blood; and (iii) when the tissue contains a second volume of blood; to produce two separate absorption signals a first one of which is proportional to the absorption of said frequency varying light by said tissue containing the first volume of blood versus frequency and a second of which is proportional to the absorption of said frequency varying light by said tissue containing the second volume of blood versus frequency; and d) generating means for generating said differential signal which is proportional to the difference between the light detected versus frequency for each signal detected in (c) (i) and (ii) above.
Claim 16
Dependent Claim
13 words
The apparatus of claim 12 wherein the tuner comprises an acousto-optical tunable filter.
Claim 17
Dependent Claim
31 words
The apparatus of claim 12 including a beam splitter dividing the frequency varied beam of light into two beams, one of which traverses a greater volume of blood than the other.
Claim 18
Dependent Claim
21 words
The apparatus of claim 12 including clamp means for varying the volume of blood in the tissue traversed by the light.
Claim 19
Dependent Claim
14 words
The apparatus of claim 15 wherein the clamp means is an optically transparent body.
References Cited (Backward Citations)
DE74428C
Cited
US1758088A
Cited
CH160768A
Cited
US2721942A
Cited
US3463142A
Cited
US3638640A
Cited
US3614450A
Cited
US3926527A
Cited
US3958560A
Cited
US3963019A
Cited
US4033330A
Cited
US4169676A
Cited
US4029085A
Cited
US4321930A
Cited
US4380240A
Cited
US4267844A
Cited
US4398541A
Cited
US4266554A
Cited
US4306877A
Cited
US4513751A
Cited
US4427889A
Cited
US4523279A
Cited
US4490845A
Cited
US4586513A
Cited
US4485820A
Cited
US4621643A
Cited
US4653498A
Cited
US4653498B1
Cited
US4570638A
Cited
US4768516A
Cited
US4817623A
Cited
US4603700A
Cited
EP0152979A1
Cited
US4725147A
Cited
US4655225A
Cited
US4704029A
Cited
US4759369A
Cited
US4832484A
Cited
US4750496A
Cited
US4867557A
Cited
US4785814A
Cited
US4805623A
Cited
US4796636A
Cited
US4863265A
Cited
US4854699A
Cited
US4927264A
Cited
US4882492A
Cited
US4883055A
Cited
WO1990007905A1
Cited
US5028787A
Cited
US5178142A
Cited
US5099123A
Cited
US5183042A
Cited
US4975581A
Cited
EP0404562A2
Cited
EP0407992A1
Cited
US5054487A
Cited
US5112124A
Cited
US5137023A
Cited
US5277181A
Cited
US7511341B2
Cited
US7511229B2
Cited
US7725502B1
Cited
US7527514B2
Cited
US7806144B2
Cited
US7725441B2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-12-12 | 1998-06-13 | 1998-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-12-12 | 2002-06-13 | 2002-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-12-12 | 2006-06-13 | 2006-12-13 | $7700.00 | Window Closed / Lapsed |