Blood flowmeter and sensor part of the blood flowmeter

• US 20020120203A1
• Filed: 02/01/2002
• Published: 08/29/2002
• Est. Priority Date: 02/02/2001
• Status: Active Grant

• Current Assignee: Nippon Telegraph and Telephone Corporation
• Original Assignee: Nippon Telegraph and Telephone Corporation
• Inventors: Sawada, Renshi, Higurashi, Eiji, Ito, Takahiro
• Granted Patent: US 7,128,716 B2
• Time in Patent Office: Days
• US Class Current: 600/504
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: G01F 1/661 using light

Abstract

A sensor part of a blood flowmeter for measuring a value on blood flow in tissue of a living body is provided, in which the sensor part includes: a light emitter for emitting light to tissue of a living body; and a light detector for receiving scattered light from the tissue; a first shading block for preventing light emitted from the light emitter from directly entering the light detector; a second shading block having a predetermined gap in front of the light detector, wherein the light emitter, the light detector and the shading blocks are integrated on a semiconductor substrate.

Claims

1. A sensor part of a blood flowmeter for measuring a value on blood flow in tissue of a living body by emitting light to said tissue of a living body and receiving scattered light from said tissue of a living body, said sensor part comprising:

a light emitter for emitting light to tissue of a living body; and

a light detector for receiving said scattered light from said tissue of a living body;

wherein said light emitter and said light detector are integrated on a semiconductor substrate.

2. The sensor part as claimed in claim 1, said sensor part further comprising a first shading block on said semiconductor substrate for preventing light emitted from said light emitter from directly entering said light detector.

3. The sensor part as claimed in claim 2, said sensor part further comprising a second shading block on said semiconductor substrate in front of said light detector, said second shading block having a predetermined gap.

4. The sensor part as claimed in claim 1, said sensor part further comprising an optical waveguide on said semiconductor substrate for outputting light emitted from said light emitter to said tissue of a living body by converting said light emitted from said light emitter into convergent light or parallel light.

5. The sensor part as claimed in claim 4, said sensor part further comprising a first shading block on said semiconductor substrate for preventing light emitted from said light emitter from directly entering said light detector.

6. The sensor part as claimed in claim 5, wherein said light emitter and said light detector are monolithically integrated on said semiconductor substrate.

7. The sensor part as claimed in claim 5, said sensor part further comprising a second shading block on said semiconductor substrate in front of said light detector, said second shading block having a predetermined gap.

8. The sensor part as claimed in claim 5, wherein an edge-illuminated refracting-facet photodiode is used as said light detector.

9. The sensor part as claimed in claim 5, wherein a laser diode which emits light having a wavelength of about 1.3 μ

m is used as said light emitter.

10. The sensor part as claimed in claim 9, wherein said laser diode is a DFB laser diode.

11. The sensor part as claimed in claim 10, wherein said optical waveguide is formed by using fluorinated polyimide.

12. The sensor part as claimed in claim 11, wherein said value on blood flow is a blood flow amount, a blood amount, a blood flow speed or a pulse.

14. The blood flowmeter as claimed in claim 13, said sensor part further comprising an optical waveguide on said semiconductor substrate for emitting light emitted from said light emitter to said tissue of a living body by converting said light emitted from said light emitter into convergent light or parallel light.

15. The blood flowmeter as claimed in claim 14, said sensor part further comprising a first shading block on said semiconductor substrate for preventing light emitted from said light emitter from directly entering said light detector.

16. The blood flowmeter as claimed in claim 15, said sensor part further comprising a second shading block on said semiconductor substrate in front of said light detector, said second shading block having a predetermined gap.

17. The blood flowmeter as claimed in claim 15, said blood flowmeter further comprising:

a circuit for driving said light emitter; and

a digital signal processor for calculating said value on blood flow by processing signals received from said sensor part.

18. The blood flowmeter as claimed in claim 16, said blood flowmeter further comprising:

a circuit for driving said light emitter; and

a circuit for transmitting signals output from said sensor part by wireless.

13. A blood flowmeter for measuring a value on blood flow in tissue of a living body by emitting light to said tissue of a living body and receiving scattered light from said tissue of a living body, said blood flowmeter comprising a sensor part, said sensor part comprising:

a light emitter for emitting light to tissue of a living body; and

a light detector for receiving said scattered light from said tissue of a living body;

wherein said light emitter and said light detector are integrated on a semiconductor substrate.