OPTICAL MEASUREMENT INSTRUMENT FOR LIVING BODY

• US 20080183056A1
• Filed: 11/16/2007
• Published: 07/31/2008
• Est. Priority Date: 01/25/2007
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Kiguchi, Masashi, Horita, Tadahiro, Atsumori, Hirokazu
• Granted Patent: US 8,244,324 B2
• Time in Patent Office: Days
• US Class Current: 600/310
• CPC Class Codes: A61B 2560/0252 using ambient temperature
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/7228 Signal modulation applied to the input signal sent to patient or subject; demodulation to recover the physiological signal modulation H03C
• CPC Class Codes: G01N 21/253 for batch operation, i.e. multisample apparatus analytical automats G01N35/00

Abstract

An optical measurement instrument for a living body having an optical fiber removed, which is composed so as to transmit a driving signal for the light source to a plurality of an irradiation parts, as well as to convert a transmitted and received signal, between a processing and control unit and the probe unit, to a row of serial digital signals, by having one driving device for light source and one multiplexer, inside the probe unit.

Claims

1. An optical measurement instrument for a living body comprising:

a probe unit for irradiating light onto a subject, and detecting light transmitting through or reflecting from the inside of said subject; and

a processing and control unit for transmitting a signal for light modulation to said probe unit, receiving a received light signal from said probe unit, and acquiring a living body signal,

wherein said probe unit comprising, inside thereof;

an irradiation part for irradiating light;

a digital-to-analog converter for converting said signal for light modulation from a digital signal to an analog signal;

at least one driving device for light source for receiving said signal for light modulation, which was converted to the analog signal, and for emitting the driving signal for light source;

a multiplexer for timewise and sequentially distributing said driving signal for light source to said irradiation part, corresponding to said driving device for light source;

a light detection part for detecting light transmitting through or reflecting from the inside of the subject;

an analog-to-digital converter for converting the received light signal that was emitted at said light detection part, from the analog signal to the digital signal; and

a parallel-serial converter for converting the received light signal that was converted to the digital signal, from a parallel signal to a serial signal,

wherein the digital signal is transmitted and received between said probe unit and said processing and control unit.

2. The optical measurement instrument for the living body according to claim 1, where said probe unit comprises, inside thereof:

a monitor photodiode for monitoring intensity of light irradiated onto the subject at said irradiation part; and

the analog-to-digital converter for converting the monitoring signal emitted at said monitor photodiode, from the analog signal to the digital signal, wherein said monitoring signal is transmitted to said processing and control unit, and said received light signal that was transmitted from said light detection part to said processing and control unit, is divided by said monitoring signal.

3. The optical measurement instrument for the living body according to claim 1, wherein said probe unit comprises, inside thereof:

a monitor photodiode for monitoring intensity of light irradiated onto the subject at said irradiation part; and

the analog-to-digital converter for converting the monitoring signal emitted at said monitor photodiode, from the analog signal to the digital signal, wherein intensity of light emitted at said irradiation part is maintained nearly constant, by transmitting said monitoring signal to said processing and control unit, and adjusting said signal for light modulation based on said monitoring signal.

4. The optical measurement instrument for the living body according to claim 1, comprising a plurality of said multiplexers, wherein said driving signal for light source is transmitted from said one driving device for light source to said plurality of the multiplexers.

5. The optical measurement instrument for the living body according to claim 1, comprising a plurality of said driving devices for light sources and said multiplexers, wherein modulating signals, each having different modulation frequencies or codes, are transmitted to each of a plurality of said driving devices for light sources, and said driving signals for light sources, which are modulated to said modulating signals, each having different modulation frequencies or codes, are transmitted to each of said multiplexers.

6. An optical measurement instrument for a living body comprising:

a probe unit for irradiating light onto a subject, and detecting light transmitting through or reflecting from the inside of said subject; and

a processing and control unit for transmitting a signal for light modulation to said probe unit, receiving a received light signal from said probe unit, and acquiring a living body signal,

wherein said probe unit comprising, inside thereof;

at least two irradiation parts for irradiating light; and

at least one light detection part for detecting light transmitting through or reflecting from the inside of the subject;

wherein light irradiated at each of the irradiation parts is emitted independently timewise, and subjected to intensity modulation, and in said processing and control unit, said received light signal is subjected to a lock-in detection processing.