Method and means for generating synthetic spectra allowing quantitative measurement in near infrared measuring instruments

• US 5,324,979 A
• Filed: 07/24/1992
• Issued: 06/28/1994
• Est. Priority Date: 09/26/1990
• Status: Expired due to Term

• Current Assignee: Futrex, Inc.
• Original Assignee: Futrex, Inc.
• Inventors: Rosenthal, Robert D.
• Primary Examiner(s): Dzierzynski, Paul M.
• Assistant Examiner(s): NGUYEN, KIET TUAN
• Application Number:
  US07/917,998
• Time in Patent Office: 704 Days
• Field of Search: 250/504 R, 250/495.1, 250/494.1, 250/338.1, 250/493.1
• US Class Current: 250/504.00R
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: G01J 3/108 for measurement in the infrared range
• CPC Class Codes: G01N 21/255 Details, e.g. use of specially adapted sources, lighting or optical systems
• CPC Class Codes: G01N 21/359 using near infrared light
• CPC Class Codes: G01N 2201/0621 Supply

Abstract

A method and means for generating synthetic spectra allowing quantitative measurement utilizes dual chip alternatively energized IREDs with optical bandpass filter(s) passing two optical bands which is be combined with curvilinear interpolation to be utilized in a low cost small size quantitative measuring instrument.

Claims

1. A quantitative near-infrared analysis instrument for non-invasive measurement of a blood analyte present in a body part of a subject, said analysis instrument comprising:

(a) an introducing means comprising a near-infrared energy source for introducing near-infrared energy into blood present in a body part of a patient, said near infrared energy source comprising at least one infrared emitting diode having at least two chips and producing at least two separate wavelengths;

(b) detecting means for detecting near-infrared energy emerging from the body part and generating a signal based upon each of said at least two separate wavelengths from each of said at least two chips from said one infrared emitting diode; and

(c) processing means for calculating a synthetic spectra for ,curvilinear interpolation based upon the signal generated from said detection means.

2. The near-infrared analysis instrument of claim 1, wherein said at least one infrared emitting diode having at least two chips is used in combination with a filter means for passing two separate wavelengths.

3. The near-infrared analysis instrument of claim 2, wherein said filter means is a single filter having two bandpasses.

4. The near-infrared analysis instrument of claim 2, wherein said filter means comprises separate filters, each with a single bandpass.

5. The near-infrared analysis instrument of claim 1, wherein said near-infrared energy source comprises six infrared emitting diodes each having at least two chips and producing at least two separate wavelengths.

6. A quantitative near-infrared analysis instrument for non-invasive measurement of a blood analyte present in a body part of a subject, said instrument comprising:

(a) an introducing means comprising a near-infrared energy source for introducing near-infrared energy into blood present in a body part of a patient, said near infrared energy source comprising six infrared emitting diodes each having at least two chips and wherein each of said two chips produces a separate wavelength;

(b) detecting means for detecting near-infrared energy emerging from the body part and generating a signal based upon said separate wavelength from each of said at least two chips from each of said six infrared emitting diodes; and

(c) processing means for calculating a synthetic spectra for curvilinear interpolation based upon the signal generated from said detection means.

7. A quantitative near-infrared analysis instrument for non-invasive measurement of a blood analyte present in a body part of a subject, said analysis instrument comprising:

(a) an introducing means comprising a near-infrared energy source for introducing near-infrared energy into blood present in a body part of a patient, said near infrared energy source comprising seven infrared emitting diodes each having at least two chips and wherein each of said two chips produces a separate wavelength;

(b) detecting means for detecting near-infrared energy emerging from the body part and generating a signal based upon said separate wavelength from each of said at least two chips from each of said seven infrared emitting diodes; and

(c) processing means for calculating a synthetic spectra for curvilinear interpolation based upon the signal generated from said detection means.

8. The near-infrared analysis instrument of claim 7, wherein each of said seven infrared emitting diodes having at least two chips is used in combination with a filter means for passing two separate wavelengths.

9. The near-infrared analysis instrument of claim 8, wherein said filter means is a single filter having two bandpasses.

10. The near-infrared analysis instrument of claim 8, wherein said filter means comprises separate filters, each with a single bandpass.

11. The near-infrared analysis instrument of claim 7, wherein said seven infrared emitting diodes emit energy at selected wavelengths from approximately 600 nanometers to approximately 1100 nanometers.

12. A quantitative near-infrared analysis instrument for non-invasive measurement of a blood analyte present in a body part of a subject, said analysis instrument comprising:

(a) an introducing means comprising a near-infrared energy source for introducing near-infrared energy into blood present in a body part of a patient, said near infrared energy source comprising at least one infrared emitting diode having three chips and producing at least three separate wavelengths;

(b) detecting means for detecting near-infrared energy emerging from the body part and generating a signal based upon each of said at least three separate wavelengths from each of said three chips from said one infrared emitting diode; and

(c) processing means for calculating a synthetic spectra for curvilinear interpolation based upon the signal generated from said detection means.