Non-invasive blood analyzer

• US 5,791,345 A
• Filed: 11/30/1995
• Issued: 08/11/1998
• Est. Priority Date: 09/03/1993
• Status: Expired due to Fees

• Current Assignee: Ken Ishihara
• Original Assignee: Toa Medical Electronics Co., Ltd.
• Inventors: Maekawa, Yasunori, Suzuki, Akio, Watanabe, Mitsuru, Ishihara, Ken, Kouchi, Yasuhiro, Yamamoto, Hiroshi, Asano, Kaoru
• Primary Examiner(s): Bahr, Jennifer
• Assistant Examiner(s): WINAKUR, ERIC FRANK
• Application Number:
  US08/565,046
• Time in Patent Office: 985 Days
• Field of Search: 128/633, 128/637, 128/664, 128/665, 356/39
• US Class Current: 600/368
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14535 for measuring haematocrit
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: G01N 15/01 specially adapted for biological cells, e.g. blood cells investigating sedimentation of particle suspensions in blood G01N15/05
• CPC Class Codes: G01N 15/0227 using imaging; using holography
• CPC Class Codes: G01N 2021/1791 stroboscopic; pulse gated; time range gated
• CPC Class Codes: G01N 21/53 within a flowing fluid, e.g. smoke

Abstract

A non-invasive blood analyzer is intended to capture images of a prescribed volume of blood in a blood vessel in a non-invasive manner and with a good contrast without collecting blood from a living body. The non-invasive blood analyzer includes a light application device for illuminating a detection region of vessels contained in a part of a living body, an image capturing device for capturing images of the detection region illuminated by the light application device, and an analyzer for analyzing blood components contained in the detection region by processing the images captured by the image capturing device. The image capturing device includes an object lens for converging the reflected light from the detection region. The light application device illuminates the detection region at an incident angle larger than an aperture angle of the object lens with respect to the detection region to provide dark-field illumination.

Claims

1. A non-invasive blood analyzer comprising:

light application means for applying light to a detection region in a blood vessel contained in a part of a living body;

image capturing means, responsive to light reflected from said detection region, for capturing an image of the detection region from the reflected light; and

analysis means for analyzing characteristics of blood components contained in the detection region by processing the image captured by the image capturing means,

the image capturing means including a lens for converging the light reflected from the detection region, and the light application means applying light to the detection region at an incident angle larger than an aperture angle of the lens with respect to the detection region to provide dark-field illumination.

2. A non-invasive blood and analyzer according to claim 1 wherein the analysis means analyzes captured images of blood cells.

3. A non-invasive blood analyzer according to claim 1 wherein the image capturing means captures images of bilirubin in blood.

4. The non-invasive blood analyzer of claim 3, wherein the light application means illuminates the detection region with a blue and a green light to aid the image capturing means in capturing images of bilirubin in blood.

5. A non-invasive blood analyzer according to claim 1 wherein the image capturing means captures images of oxyhemoglobin in blood.

6. The non-invasive blood analyzer of claim 5, wherein the light application means illuminates the detection region with at least one light emitting element for emitting at least one of red, green and blue light.

7. The non-invasive blood analyzer of claim 6, wherein the light application means illuminates the detection region with a red light and one of a blue and a green light to aid the image capturing means in capturing images of oxyhemoglobin in blood.

8. A non-invasive blood analyzer according to claim 1 wherein the light application means comprises a plurality of light emitting elements disposed around the lens and light guiding means for directing light emitted by the light emitting elements to the detection region.

9. The non-invasive blood analyzer of claim 8, wherein the light application means includes light emitting elements for emitting red, green and blue light.

10. The non-invasive blood analyzer of claim 9, wherein the light application means illuminates the detection region with a red light and one of a blue and a green light to aid the image capturing means in capturing images of oxyhemoglobin in blood.

11. The non-invasive blood analyzer of claim 9, wherein the light application means illuminates the detection region with a blue and a green light to aid the image capturing means in capturing images of bilirubin in blood.

12. A non-invasive blood analyzer according to claim 1 wherein the light application means comprises a plurality of light emitting elements disposed around the lens, each of the light emitting elements emitting light of one of a plurality of different wavelengths, light guiding means for directing light emitted by the light emitting elements to the detection region, and control means for selectively energizing light emitting elements to emit light of different wavelengths.

13. The non-invasive blood analyzer of claim 12, wherein the light application means includes light emitting elements for emitting red, green and blue light.

14. The non-invasive blood analyzer of claim 13, wherein the light application means illuminates the detection region with a red light and one of a blue and a green light to aid the image capturing means in capturing images of oxyhemoglobin in blood.

15. The non-invasive blood analyzer of claim 13, wherein the light application means illuminates the detection region with a blue and a green light to aid the image capturing means in capturing images of bilirubin in blood.