JP2005300451A - Light irradiation device and glucose concentration measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light irradiation device and a glucose concentration measuring device capable of emitting a light of high directivity, while reducing a side lobe. <P>SOLUTION: The glucose concentration measuring device comprises a plurality of wide-band light sources 7-11 emitting lights of different wavelength bands, a spectral division part 3 for spectrally dividing the light of a specified wavelength of the lights incident from the light sources 7-11, and a computer 49 for making the light emitted from any one wide-band light source to be incident on the spectral division part 3, according to the specified wavelength spectrally divided by the spectral section part 3. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a light irradiation device that splits and outputs a specific wavelength from light in a predetermined band, and a glucose concentration measurement device using the light irradiation device.

Conventionally, blood glucose concentration measurement has been performed for the determination of diabetes, and in particular, glucose concentration measurement has been performed in order to examine blood glucose levels that determine the insulin dose of diabetic patients. The measurement of glucose concentration is generally performed by directly analyzing blood collected from a finger or an arm. Since the glucose concentration in the blood in the patient's body changes depending on the measurement conditions such as before and after meals and after exercise, frequent glucose concentration measurement is necessary to obtain an accurate blood glucose level.
However, the above-described method for directly analyzing the collected blood has a problem in that blood must be collected by inserting an injection needle or the like every time the glucose concentration is measured, and the burden on the patient is large.

In order to solve this problem, non-invasive detection of light emitted outside the living body by irradiating a living tissue such as a finger, arm, earlobe, etc. A glucose concentration measurement method has been proposed (see, for example, Patent Document 1). In the method of Patent Document 1, light in a predetermined wavelength band emitted from a halogen lamp is guided to a spectroscope by an optical fiber, and incident on the living body by irradiating the living body with light having a specific wavelength dispersed by the spectroscope. And receiving the light diffused in the living body and returning from the living body surface to the outside of the living body, and calculating the glucose concentration by analyzing the spectrum of the received light.
JP 2000-131322 A (FIG. 3 etc.)

The method disclosed in Patent Document 1 uses a large number of light-emitting fibers and light-receiving fibers to increase the amount of light detected and the amount of light detected, thereby increasing the amount of information on the detected glucose concentration. However, most of the light emitted from the halogen lamp has an inconvenience that it leaks outside without entering the optical fiber.
In order to avoid such inconveniences, for example, a plurality of broadband light sources are used in place of the halogen lamp, and the light emitted from these light sources is combined and then guided to the spectroscope. A technique for performing spectroscopic and irradiating a living body has been proposed. According to this method, since the intensity of light in each wavelength band can be increased, light with relatively high intensity can be efficiently incident on the living body.

  By the way, in the spectroscope, due to the characteristics, a noise component called a side lobe is always generated in the peripheral wavelength of the light (main lobe) to be dispersed. Conventionally, since light having substantially the same intensity emitted from one halogen lamp is dispersed, the light intensity of the side lobe with respect to the main lobe has been weak. However, when a plurality of light sources are used, the light intensity of each light source is often different. In this case, the side lobe has a great influence on the measurement depending on the wavelength of the spectrum, and there is a problem that the glucose concentration cannot be measured with high accuracy.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a light irradiation device and a glucose concentration measuring device capable of reducing side lobes and emitting light having high directivity.

In order to achieve the above object, the present invention provides the following means.
The present invention includes a plurality of broadband light sources that emit light having different wavelength bands, a spectroscopic unit that splits light of a specific wavelength among light incident from the broadband light source, and the specific wavelength that is split by the spectroscopic unit. Accordingly, there is provided a light irradiating apparatus including a control unit that causes light emitted from any one of the broadband light sources to enter the spectroscopic unit.

  According to the present invention, the light emitted from the broadband light source is guided to the spectroscopic means, and the light having a specific wavelength is split and output from the spectroscopic means. In this case, since the light incident on the spectroscopic means is light emitted from any one of the broadband light sources determined according to the specific wavelength, side lobes are generated over the wavelength bands emitted by the other broadband light sources. This can be avoided, and the side lobes can be reduced.

Further, the light irradiation apparatus described above includes a light blocking unit that selectively passes or blocks light from any broadband light source between the broadband light source and the spectroscopic unit, and the control unit includes the control unit, It is preferable to control the light blocking means according to a specific wavelength.
According to the present invention, since the light blocking means for passing or blocking the light emitted from each broadband light source is provided between the broadband light source and the spectroscopic means, the light emitted from one broadband light source with a very simple configuration. Can be guided to the spectroscopic means.

The light irradiation device includes an optical switch between the broadband light source and the spectroscopic unit, and the control unit turns on and off the optical switch, thereby causing the spectroscopic unit to emit light from any one of the broadband light sources. It is preferable to make it enter into.
According to the present invention, since the optical switch is provided between the broadband light source and the spectroscopic means, it is possible to guide the light emitted from any one light source to the spectroscopic means with a simple configuration and control processing. Become.

Moreover, it is preferable that the said light irradiation apparatus provides the filter which adjusts the intensity | strength of the light radiate | emitted from the said broadband light source between the said broadband light source and the said spectroscopy means.
According to the present invention, since the intensity of light emitted from each broadband light source is adjusted by the filter, the wavelength purity of the light can be improved, and even within the wavelength band emitted from one broadband light source, the side lobe is improved. Can be reduced.

Further, the present invention provides a light irradiation apparatus according to any one of claims 1 to 5, which irradiates a living body with light, a light detecting means for detecting return light from the living body, and the light detecting means. A glucose concentration measuring device is provided, comprising a computing means for calculating the glucose concentration in the living body based on the spectrum of the light detected by.
According to the present invention, since the light irradiation device that irradiates light with low directivity with less noise can be used, it is possible to irradiate the living body with light with less noise, and to realize highly accurate glucose concentration measurement. It becomes.

  According to the light irradiation apparatus according to the present invention, it is possible to reduce the side lobes. As a result, there is an effect that light with high directivity with less noise can be emitted.

  Hereinafter, a glucose concentration measuring apparatus according to an embodiment of the present invention will be described in detail in the order of [first embodiment] and [second embodiment] with reference to the drawings.

[First Embodiment]
FIG. 1 is a diagram showing a configuration of a glucose concentration measuring apparatus according to the first embodiment of the present invention. As shown in FIG. 1, a glucose concentration measuring apparatus 1 according to this embodiment includes a light irradiation unit (light irradiation apparatus) 4 that irradiates a sample with measurement light while changing the wavelength over a predetermined wavelength band, and a living body. Based on the light detection part (light detection means) 5 for detecting the light diffused or transmitted in A outside the living body A and the spectrum of the light detected by the light detection part 5, the glucose concentration in the living body A is calculated. A calculation unit (calculation means) 6 is provided as a main component.

The light irradiation unit 4 includes a plurality of broadband light sources 7 to 11, a light source 2 that generates light to irradiate the living body A, an optical switch 12 provided on the output side of the light source 2, and a light switch 2 to the optical switch 12. And a spectroscopic unit (spectral means) 3 that splits the light guided through.
The light source 2 includes a plurality of broadband light sources 7 to 11, for example, ASE light sources 7 to 9 and SLD light sources 10 and 11. Each broadband light source 7 to 11 has a different wavelength band of the emitted light. In the example shown in FIG. 2, for example, a near infrared light region (wavelength of about 1400 to 1700 nm) required for measuring the glucose concentration is divided into five wavelength regions, and each divided wavelength band corresponds to each broadband light source 7. Assigned to ~ 11. Specifically, the broadband light source 7 has a wavelength of 1430 to 1520 nm, the broadband light source 8 has a wavelength of 1520 to 1610 nm, the broadband light source 9 has a wavelength of 1650 to 1690 nm, the broadband light source 10 has a wavelength of 1360 to 1430 nm, and the broadband light source 11 has a wavelength of 1610 to 1650 nm. It has a band. Each of the broadband light sources 7 to 11 has a wavelength band of several tens to several hundreds of nm and generates light having a spatially small diameter of about several tens of μm.

  The light source 2 and the optical switch 12 are connected by an optical fiber 24. As described above, since the broadband light sources 7 to 11 are light sources that emit light having a spatially small diameter, if a point conjugate with the light source is positioned on the end face of the optical fiber 24, the light emitted from the broadband light source is high. The light can be efficiently incident on the optical fiber 24. The optical fiber 24 may be a single mode fiber or a multimode fiber, but preferably has an end face shape corresponding to the shape of the light output port of each light source.

The optical switch 12 includes a plurality of optical switches 12 a to 12 e provided corresponding to the broadband light sources 7 to 11 constituting the light source 2. These optical switches 12 a to 12 e are turned on / off by a computer (control means) 49 described later, thereby causing light emitted from any one of the broadband light sources to enter the spectroscopic unit 3.
The light emitted from the optical switch 12 is guided to the spectroscopic unit 3 by the optical fiber 29. The optical fiber 29 is not particularly limited, and may be a single mode fiber or a multimode fiber.

The spectroscopic unit 3 is an acousto-optic variable wavelength filter 25 (AOTF: Acousto-Optic Tunable Filter) that further divides and emits only light of a specific wavelength of incident light according to an input high frequency frequency. , Hereinafter referred to as AOTF), a filter control unit 26 that outputs a high frequency signal while changing the frequency thereof at a predetermined speed, an oscillator 27 that outputs a high frequency signal of a predetermined frequency, and a multiplier 28. Yes.
The filter control unit 26 outputs a high-frequency signal (hereinafter referred to as “control signal”) whose frequency sequentially changes at a predetermined speed based on the frequency variable signal input from the computer. On the other hand, the oscillator 27 outputs a high-frequency signal (hereinafter referred to as “chopping signal”) having a constant frequency (hereinafter referred to as “chopping frequency”). The multiplier 28 multiplies the control signal output from the filter control unit 26 and the chopping signal output from the oscillator 27 and supplies the result to the AOTF 25. As a result, a control signal chopped at the chopping frequency is supplied to the AOTF 25.
The chopping signal output from the oscillator 27 is also supplied to a lock-in detector 47 of the arithmetic unit 6 described later.

  The polarized light output from the AOTF 25 is guided to the exit of the apparatus main body 31 by the optical fibers 30 and 32. The optical fiber 30 disposed at the outlet of the AOTF 25 is not particularly limited, but all the light can be incident from the end face of the optical fiber 30 even if the output angle of the AOTF 25 varies. It is preferable to employ a multimode fiber having a relatively large core diameter. According to the multimode fiber, it is possible to allow the light emitted from the AOTF 25 to enter without leakage even when the optical path fluctuates due to mechanical deviation or deformation of the optical system.

  Further, between the optical fibers 30 and 32, there is provided an optical branching portion 33 that branches light incident from the AOTF 25 in two directions. For example, as shown in FIG. 3, the light branching unit 33 includes a collimating lens 34 disposed to face the end face of the optical fiber 30, and a beam that branches the light collimated by the collimating lens 34 in two directions. A splitter 35 and two condensing lenses 37 and 38 for condensing the branched collimated light on the two optical fibers 32 and 36 are provided.

  One of the branched optical fibers 32 is connected to the outlet of the apparatus main body 31, and the other optical fiber 36 is configured to guide the branched light to a reference light detector 44 of the light detection unit 5 described later. Has been. The branching ratio of the beam splitter 35 in the optical branching unit 33 is set so that, for example, the measurement light traveling toward the exit side of the apparatus main body 31 is about 95% and the reference light traveling toward the reference light detector is about 5%.

  A connector 39 is provided at the outlet of the apparatus main body 31, and one optical fiber 32 branched at the light branching portion 33 is connected thereto. A measurement probe 40 that is brought into contact with the surface of the living body A tissue is provided outside the apparatus main body 31, and the measurement probe 40 and the connector 39 are connected by an irradiation optical fiber 41. Connection of the optical fibers 32 and 41 in the connector 39 is performed by arranging the end faces of the optical fibers 32 and 41 having the same diameter core so as to abut each other. The end faces of the optical fibers 32 and 41 are, for example, PC-polished so that measurement light emitted from the end face of one optical fiber 32 can be efficiently delivered into the other optical fiber 41.

  As shown in FIG. 4, the measurement probe 40 has a single irradiation optical fiber 41 at its center, as shown in FIG. 4, and a plurality of light receiving optical fibers 42 spaced around the periphery. Is arranged. That is, when the apparatus is operated with the distal end surface 40a of the measurement probe 40 in close contact with the surface of the living body A tissue, the measurement light emitted from the center of the measurement probe 40 enters the living body A and is diffused or transmitted. Then, the light returns to the surface of the living body A and is received as signal light by the light receiving optical fiber 42 arranged around the irradiation optical fiber 41.

  The distance between each light receiving optical fiber 42 and the irradiation optical fiber 41 is such that the measurement light emitted from the irradiation optical fiber 41 is received by the light receiving optical fiber 42 through a predetermined optical path length. Is set to In the case of the glucose concentration measuring apparatus 1 according to the present embodiment, the measuring light is arranged at a distance of about 0.4 to 0.8 mm so that the measuring light reaches the dermis region containing a lot of glucose. As a result, the signal light received by the light receiving optical fiber 42 contains a lot of light that has reached the depth of the dermis in the living body A tissue. The light receiving optical fibers 42 are bundled to form a fiber bundle, and are connected to the apparatus main body 31 by other connectors 43.

  The light detection unit 5 includes two light detectors 44 and 45. These photodetectors 44 and 45 are, for example, PbS sensors or InGaAs sensors. As described above, one reference light detector 44 is disposed opposite to the end face of one optical fiber 36 branched at the light branching section 33, and detects the reference light emitted from the optical fiber 36. The detection signal is output. The other signal light detector 45 is disposed opposite to the end face of the light receiving optical fiber 42 constituting the fiber bundle, and the signal light received and propagated by these light receiving optical fibers 42. Is detected and a detection signal is output.

The arithmetic unit 6 amplifies the detection signal of the signal light detector 45 and the detection signal of the reference light detector 44, and outputs only a signal having a specific frequency from the electric signal output from the amplifier 46. Based on the lock-in detector 47 to be extracted, the A / D converter 48 for converting the electrical signal output from the lock-in detector 47 into a digital signal, and the digital signal output from the A / D converter 48 And a computer 49 for calculating the glucose concentration.
The lock-in detector 47 detects an electrical signal from the amplifier 46 in synchronization with the chopping signal supplied from the oscillator 27.

  Further, an output signal obtained by A / D converting the electrical signal detected by the lock-in detector 47 is input to the computer 49. In the computer 49, the calculation processing of the glucose concentration based on the digital signal output from the A / D converter 48 and the frequency variable signal supplied to the filter control unit 26 and the on / off control of the optical switch 12 are performed in parallel. Has been done.

Specifically, the calculation processing of the glucose concentration is based on the spectral distribution of the output signal obtained based on the plurality of output signals obtained from the A / D converter 48 and the frequency variable signal. Absorbance in a wavelength region, for example, a region in the vicinity of a wavelength of 1600 nm, is obtained, and a glucose concentration is obtained based on this.
On the other hand, the on / off control of the optical switch 12 is performed as follows.
First, as shown in FIG. 5, the computer 49 includes an optical switch control table in which ON / OFF control timings for the optical switches 12 a to 12 e are set in advance according to a specific wavelength to be dispersed. Then, the computer 49 controls on / off of each of the optical switches 12a to 12e based on the frequency variable signal supplied to the filter control unit 26 and the optical switch control table shown in FIG.
The computer 49 is provided with a display (not shown) so that the glucose concentration value calculated by the computer 49 is displayed.

The operation of the glucose concentration measuring apparatus 1 according to this embodiment configured as described above will be described below.
In order to measure the glucose concentration of the body fluid in the living body A using the glucose concentration measuring apparatus 1 according to the present embodiment, the distal end surface 40a of the measuring probe 40 is brought into close contact with the living body A, for example, the surface of the fingertip. The measurement site may be a palm, a forearm or the like in addition to the fingertip.

In this state, the light irradiation device 4 is operated. By operating all the broadband light sources 7 to 11 of the light irradiation device 4, the light of each wavelength band emitted from the broadband light sources 7 to 11 is incident on the end face of the optical fiber 24 without leakage. The light in each wavelength band transmitted through the optical fiber 24 is incident on the corresponding optical switches 12a to 12e.
On the other hand, based on the frequency variable signal supplied to the filter control unit 26, the computer 49 leads the light of any one of the broadband light sources corresponding to the wavelength to be dispersed to the AOTF 25 prior to the spectral timing of the AOTF 25. In addition, the on / off of the optical switches 12a to 12e is controlled. For example, when the wavelength lambda _X being dispersed by AOTF25 is applicable between 1610nm from 1520 nm, the computer 49, based on the optical switch control table shown in FIG. 5, for turning on and off the light switch 12. Specifically, the optical switch 12b is turned on, and the other optical switches 12a and 12c to 12e are turned off. Thereby, only the light of the broadband power supply 8 (ASE2) corresponding to the optical switch 12b is guided to the AOTF 25 through the optical switch 12b. A solid line portion in the upper diagram of FIG. 6 represents light guided to the AOTF 25.

Based on the frequency of the control signal that is intermittently supplied from the multiplier 28 according to the chopping frequency, the AOTF 25 outputs the light having the wavelength λ _X out of the light having the wavelength band of 1520 nm to 1610 nm emitted by the broadband light source 8. The light is split and emitted as measurement light.
As a result, light having a predetermined wavelength λ _X is intermittently emitted from the AOTF 25 at the chopping frequency.
In this case, since only the light of the broadband power supply 8 (ASE2) is input to the AOTF 25, the wavelength emitted by another broadband light source, for example, the broadband power supply 7 (ASE1), as shown in the lower diagram of FIG. Generation of side lobes over the band can be avoided. As a result, it is possible to emit measurement light with less directivity and less directivity from the AOTF 25, and there is an effect that the S / N ratio can be improved and the measurement accuracy can be improved.

  The measurement light emitted from the AOTF 25 is sent to the optical branching unit 33 through the optical fiber 30, and a part of the measurement light is branched by the optical branching unit 33 as reference light. The branched reference light is detected as it is by the reference light detector 44 arranged to face the end face of the reference optical fiber 36.

  The remaining measurement light from which the reference light has been separated is incident on the optical fiber 32 by the condenser lens 37 (see FIG. 3), and is incident on the irradiation optical fiber 41 of the measurement probe 40 connected by the connector 39. Be made. Since the connector 39 is connected so that the end faces of the optical fibers 32 and 41 having the same diameter core are abutted against each other, the transmitted measurement light does not leak to the outside and the front end face of the measurement probe 40 The light is emitted from 40a.

  The measurement light incident in the living body A collides with the living body A tissue and diffuses while traveling in the living body A. The measurement light absorbs light in a specific wavelength region according to the components of the living body A tissue and body fluid that pass therethrough. Therefore, the signal light that has been diffused in the living body A and returned to the surface of the living body A and emitted to the outside of the living body A has a reduced amount of light in a specific wavelength region according to the living body A tissue or body fluid that has passed through. It will be.

Since the light receiving optical fiber 42 is fixed at a constant distance from the irradiation optical fiber 41 as described above, the light receiving optical fiber 42 receives signal light containing a large amount of light that has reached a depth corresponding to the distance. In the case of the present embodiment, since the measurement light reaches the dermis region and then received as signal light by the light receiving optical fiber 42, the received signal light contains a lot of glucose information.
The received signal light is returned into the apparatus main body 31 through the light receiving optical fiber 42 and detected by the signal light detector 45 disposed opposite to the end face of the light receiving optical fiber 42.

  When output signals from the signal light detector 45 and the reference light detector 44 are input to the arithmetic unit 6, they are amplified by the amplifiers 46. The magnitude of the signal light detected by the signal light detector 45 varies with fluctuations in the intensity of the light incident on the living body A, that is, the measurement light emitted from the AOTF 25. Therefore, a part of the measurement light before entering the living body A is detected by the reference light detector 44 as the reference light, and is subtracted from the signal light received by the computer 49 described later, whereby the measurement light emitted from the AOTF 25 It is possible to eliminate fluctuations in signal light intensity due to fluctuations in intensity. In the glucose concentration measuring apparatus 1 according to the present embodiment, the branching ratio in the light branching unit 33 is set to about 95% measuring light and about 5% reference light, so that the measuring light is attenuated in the living body A. It is possible to effectively remove the fluctuation of the signal light intensity due to the fluctuation of the intensity of the measurement light by equalizing the levels of the signal light and the reference light.

  The output signals from the nuclear detectors 44 and 45 amplified by the amplifier 46 are passed through the lock-in detector 47, respectively. Thereby, an output signal is detected in synchronization with the chopping frequency.

  The output signals detected by the lock-in detector 47 are converted into digital signals by the A / D converter 48 and input to the computer 49. The computer 49 obtains a wavelength characteristic indicating the relationship between the output signal and the wavelength information based on the digital signal and the frequency variable signal supplied to the filter control unit 26. Among the obtained wavelength characteristics, a predetermined wavelength region, For example, the glucose concentration in the living body A is calculated by obtaining the output signal value in the region near the wavelength of 1600 nm. Then, the calculated glucose concentration value is displayed on the display.

As described above, according to the glucose concentration measuring apparatus 1 according to the present embodiment, light in a predetermined wavelength band emitted from any one of the broadband light sources is incident on the AOTF 25, so that the wavelength bands emitted by other broadband light sources Thus, the occurrence of side lobes can be avoided, and the side lobes can be reduced. As a result, it is possible to irradiate the living body with measurement light with less directivity and less directivity, so that the measurement accuracy of the glucose concentration can be improved.
In particular, as shown in FIG. 2, when the intensity of light emitted from each broadband light source is different, the side lobes can be further effectively reduced. In other words, in the case of a conventional apparatus, when the main lobe belongs to a wavelength band with low light intensity, and the side lobe occurs over a wavelength band with high light intensity, the influence of the side lobe on the measurement is large. It will be a thing. However, according to the present embodiment, since only the light in the wavelength band to which the wavelength to be dispersed belongs is guided to the AOTF 25, it is possible to remove the side lobe generated in the wavelength band with high light intensity, compared with the conventional case. Thus, the side lobe can be greatly reduced.

  Further, by adopting an optical switch as means for blocking light other than the target band, only light emitted from one broadband light source can be guided to the AOTF 25 with a very simple configuration. Note that the same effect can be obtained by using an optical shutter (light blocking means) instead of the above-described optical switch.

[Second Embodiment]
Next, a glucose concentration measuring apparatus according to the second embodiment of the present invention will be described.
In the glucose concentration measuring apparatus according to the present embodiment, a filter (for example, an ND filter) is provided between the broadband light sources 7 to 11 and the AOTF 25 in the configuration of the glucose concentration measuring apparatus according to the first embodiment described above. And it adjusts so that the intensity | strength of the light radiate | emitted from each broadband light source 7-11 may become substantially the same with this filter. Thereby, the wavelength purity of light can be improved, and side lobes can be reduced even within a wavelength band emitted from one broadband light source.
Furthermore, an output stable light source is adopted as each of the broadband light sources 7-11. As a result, the light intensity of each wavelength emitted from each of the broadband light sources 7 to 11 can be made uniform, so that the light intensity can be flattened over the entire light source 2. As a result, the light intensity of the side lobes can be made uniform in the entire wavelength band, and the measurement light emitted from the AOTF 25 can be stabilized.

As mentioned above, although embodiment of this invention has been described with reference to drawings, a specific structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.
First, the light source 2 is composed of the five broadband light sources 7 to 11. However, instead of this, two to four or six or more broadband light sources may be adopted.
Secondly, although the AOTF 25 is used as the spectroscopic unit 3, a combination of a grating and a scan mirror may be used instead.
Third, the output signals from the signal light detector 45 and the reference light detector 44 are amplified by separate amplifiers 46 and input to the computer 49 via separate lock-in detectors 47 and A / D converters 48. However, the computer 49 performs the difference processing. Instead, the difference signal obtained by inputting to the differential amplifier is converted into a single lock-in detector 47 and an A / D converter 48. May be input to the computer 49 via

It is the schematic which shows the whole structure of the glucose concentration measuring apparatus which concerns on one Embodiment of this invention. It is a figure which shows the spectrum of the light radiate | emitted by the light source of the glucose concentration measuring apparatus of FIG. It is the schematic explaining the light branching part of the glucose concentration measuring apparatus of FIG. It is a figure which shows the measurement probe front end surface of the glucose concentration measuring apparatus of FIG. It is a figure which shows the content of the optical switch control table with which the computer 49 is provided. It is a figure which shows the outline | summary of the light which injects into AOTF, and the light radiate | emitted from AOTF.

Explanation of symbols

DESCRIPTION OF SYMBOLS A Living body 1 Glucose concentration measuring device 3 Spectrometer 4 Light irradiation part 5 Light detection part 6 Calculation part 7-11 Broadband light source 12 Optical switch 25 AOTF (acoustic optical variable wavelength filter)
33 Optical branching unit 40 Measurement probe 44 Photodetector for reference 45 Photodetector for measurement 49 Computer

Claims (5)

A plurality of broadband light sources emitting light in different wavelength bands;
Spectroscopic means for spectrally splitting light of a specific wavelength among light incident from the broadband light source;
A light irradiation apparatus comprising: control means for causing light emitted from any one of the broadband light sources to enter the spectroscopic means in accordance with the specific wavelength split by the spectroscopic means. A light blocking means for selectively passing or blocking light from any broadband light source between the broadband light source and the spectroscopic means,
The light irradiation apparatus according to claim 1, wherein the control unit controls the light blocking unit according to the specific wavelength. An optical switch is provided between the broadband light source and the spectroscopic means,
The light irradiation apparatus according to claim 1, wherein the control unit causes the light of any one of the broadband light sources to enter the spectroscopic unit by turning on and off the optical switch.   4. The light emitting device according to claim 1, wherein a filter that adjusts the intensity of light emitted from the broadband light source is provided between the broadband light source and the spectroscopic unit. 5. The light irradiation apparatus according to any one of claims 1 to 4, wherein the living body is irradiated with light;
Light detecting means for detecting return light from the living body;
A glucose concentration measuring device comprising: an arithmetic means for calculating a glucose concentration in the living body based on a spectrum of light detected by the light detecting means.

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