JPH1137938A - Diffuse reflection light measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the two-dimensional information of a light absorbing substance over a wide range by providing a section for irradiating a sample with a slit-like or linear light thereby realizing an optimal detection sensitivity depending on the characteristics of the substance of a specimen. SOLUTION: When a monochromatic light is transmitted from light sources 4, 5 through an optical fiber 3 to an irradiating part 1, the light impinges vertically onto a sample (s) from the irradiating face of the optical fiber 3 constituting the irradiating part 1. The light irradiating part of the optical fiber 3 has a length in the axial direction and a slit-like or linear light is formed. The light impinging on the sample (s) is scattered by a substance contained therein and radiated again from the surface of the sample (s) with an intensity and at a position corresponding to the absorption coefficient of the substance. A detector 2 detects the intensity of the reflected light thereof. Since the light absorption coefficient is difference for different substance, the absorption sensitivity being detected is also difference for different substance but the absorption sensitivity can be regulated depending on the substance to be measured by varying the width of a light shielding section 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical measurement apparatus for irradiating a subject with light, such as an optical CT or a biological oxygen monitor, and detecting transmitted scattered light to measure information in the subject.

[0002]

2. Description of the Related Art A light measuring device that irradiates a subject with light such as visible light or near-infrared light, detects light transmitted and scattered in the subject, and non-destructively measures information in the subject. It has been known.
Optical CT and biological oxygen monitors are examples of measuring devices that apply such an optical measuring device to a living body. The present invention can be applied to an object that can transmit light such as visible light or near-infrared light, and can be applied to other animals, plants, fruits and vegetables, etc. besides living organisms.

In a light measuring device such as an optical CT, a light transmitting means and a light receiving means are arranged at a distance, the measuring light is irradiated from the light transmitting means into the subject, and the light transmitted or scattered by the subject name is transmitted. This is a device that receives light with a light receiving unit and obtains measurement data based on the measurement light, and can be applied to a noninvasive quantification method of oxyhemoglobin and deoxyhemoglobin in a living body.

[0004] In the above-mentioned light measuring device, two types are known as a measuring method when utilizing reflected light from a light scattering substance. One is as shown in FIG.
Light is emitted from a light source 1 and scattered reflected light is directly detected by a detector 2
And each point p,
This is a method of detecting light emitted from the same point p, p ′, p ″ after light incident on p ′, p ″ is slightly scattered in the sample. The other one is as shown in FIG.
This is a method of irradiating a point p from the light source 1 to light and detecting light re-emitted from a point at a distance r from the incident point.

In the case shown in FIG. 10 (a), since the distance at which light enters the inside of the sample is short, information on a portion close to the surface of the sample can be obtained. On the other hand, in the case shown in FIG. 10B, information on a deep portion of the sample can be obtained, and the depth can be selected by changing the distance r.

In the case shown in FIG. 10A, the detector 2 is replaced by a two-dimensional detector such as a CCD.
The two-dimensional distribution of light re-emitted from points such as p, p ', and p "can be easily obtained, and the distribution of the contained components on the sample surface can be obtained. On the other hand, FIG. In some cases, simply replacing the detector with a two-dimensional detector
The distribution of the re-emitted light of the light incident from one point p can only be measured. This does not directly lead to the distribution measurement of the contained components, but requires a complicated configuration such as combining position scanning on the irradiation point side.

In addition, there is a difference in the measuring method depending on whether the amount of the object to be measured is a change amount or an absolute amount at that time. When the measurement target is a living body, the background variation of the living body itself is large compared to the change due to the contained components, and it is difficult to predict the background of each sample. Therefore, the state at a certain point in time including the background is set to zero, and meaningful measurement can be often performed only for the amount of change from this point. A method using a plurality of detectors has been proposed as a method for obtaining the absolute amount at that time excluding such restrictions, for example.

[0008]

Conventionally, a two-dimensional distribution measurement as shown in FIG. 10 (a) has been known for measuring only the surface, but a measurement for a part deeper to some extent is known.
A simple two-dimensional distribution measuring method of the contained components is not known. In other words, there is a problem that the two-dimensional distribution cannot be measured in the measurement when the re-emission point is far from the incident point as shown in FIG. Therefore, it is a first object of the present invention to image a two-dimensional distribution in measurement when the re-emission point is far from the incident point.

[0009] Although imaging is limited to the amount of change from a certain point in time, it has been difficult to image the absolute amount at a certain point in time. Therefore, a second object of the present invention is to image the absolute amount as a two-dimensional image at a certain point in time.

[0010] In addition to the information on the depth, there is a problem in adjusting the measurement sensitivity in relation to the object to be measured and the substance to be detected. This is a unique problem of absorption measurement. FIG. 11 is a diagram for explaining the measurement sensitivity. FIG.
In 1, the detection signal is strongest when the target component in the sample is zero in the absorption measurement, and the detection signal decreases as the component amount increases. The characteristic curve a in FIG. 11 shows that the intensity of the detection signal is large, but the attenuation rate of the signal when the absorption of the sample increases is small. On the other hand, the characteristic curve b in FIG. 11 has a small detection signal intensity but a large signal attenuation rate.

A case where the detection signal has a large attenuation rate is called a high absorption sensitivity, and is used in distinction from the magnitude of the signal intensity. In the absorption measurement, since the amount of attenuation of the measured light from 100% is measured, the absorption sensitivity is the first factor for improving the measurement sensitivity.

Therefore, in general, even if the sensitivity of the detector is high, the measurement sensitivity is not always high, and it is necessary to increase the absorption sensitivity and secure the detection signal as much as possible. The detection sensitivity in such a case is determined by the absorption sensitivity and the SN ratio.

When the distance that light travels through the sample is large,
Even at the same sample concentration, strong absorption occurs, so that the absorption sensitivity increases. Therefore, in the case of FIG. 10A, the absorption sensitivity is low, and in the case of FIG. 10B, the absorption sensitivity is high.

However, in some cases, the absorption sensitivity may be too high. If the absorption sensitivity is high when the concentration of the sample to be detected is high to some extent, the measurement signal itself becomes extremely small, making the measurement difficult.

Accordingly, it is desirable that the absorption sensitivity can be adjusted according to the purpose of the measurement. Thus, a third object of the present invention is to make it possible to adjust the absorption sensitivity according to the purpose of measurement.

[0016]

A diffuse reflection light measuring apparatus according to the present invention uses an irradiation section for irradiating a sample with slit-like or linear light as a common component.
By the slit or linear irradiation light, to define the separation position between the irradiation position of the irradiation light and the re-emission position of the scattered light, to obtain the optimal absorption sensitivity according to the material properties of the subject, Further, the second invention detects the reflected light obtained by the slit-shaped or linear irradiation light two-dimensionally,
It is for obtaining a two-dimensional distribution of a wide range of target components.

According to the first aspect of the present invention, there is provided a diffuse reflection light measuring device for irradiating a sample with slit-like or linear light, and diffusing the sample into the sample and laterally separating from the irradiation position of the irradiation unit. And a detecting unit for detecting the reflected light re-emitted from the selected position, and the separation distance is determined according to the intensity of the reflected light detected by the detecting unit and the light absorption characteristics of the detection substance contained in the sample.

According to the diffuse reflection measuring device of the first invention,
When the sample is irradiated with slit-shaped or linear light from the irradiation unit, the light is scattered in the sample and re-emitted. The intensity of the light re-emitted from the sample and the distance from the irradiation position differ depending on the light absorption characteristics of the detection substance contained in the sample. The detection unit detects reflected light re-emitted from a position laterally separated from the irradiation position of the irradiation unit, and performs component analysis in the sample.

At this time, the separation distance between the irradiation position and the position of the reflected light detected by the detection unit is determined according to the detection intensity of the detector and the light absorption characteristics of the detection substance contained in the sample. For example, in the case of a detection substance having a small absorption coefficient, the distance through which the scattered light passes through the sample is increased by setting the separation distance large, thereby increasing the absorption sensitivity and the detection sensitivity by the detector. Further, in the case of a detection substance having a large absorption coefficient, the attenuation in the sample is large, so by setting a small separation distance, the distance that the scattered light passes through the sample is shortened, thereby lowering the absorption sensitivity, Be able to measure the desired concentration range.

Therefore, by irradiating slit or linear light and adjusting the separation distance between the irradiation position and the position of the reflected light detected by the detection unit, the optimum detection sensitivity can be obtained according to the material characteristics of the subject. By using the slit-shaped or linear irradiation light, it is possible to easily define the separation distance between the irradiation position and the position of the reflected light detected by the detection unit.

Further, as compared with the conventional method using point-like irradiation points and light receiving points (FIG. 10B), there is an advantage that a larger amount of light can be used. These are based on a configuration in which the irradiation side has a large amount of light due to extension in the length direction, and the light receiving side has a linearly long exit light area with respect to the entire length direction or the entire outer periphery of the light shielding portion. .

The diffuse reflection light measuring device according to the second invention of the present application is an irradiation section for irradiating a sample with slit-like or linear light, and re-emitted from a position laterally separated from the irradiation position of the irradiation section. And a detection unit for two-dimensionally detecting the reflected light, and a distribution of a detection substance contained in the sample is obtained from the intensity and the two-dimensional position of the reflected light detected by the detection unit.

According to the diffuse reflection measuring device of the second invention,
When the sample is irradiated with slit-shaped or linear light from the irradiation unit, the light is scattered in the sample and re-emitted. The intensity of the light re-emitted from the sample and the distance from the irradiation position differ depending on the light absorption characteristics of the detection substance contained in the sample. The detector that performs two-dimensional detection with positional resolution can two-dimensionally measure the light intensity of reflected light re-emitted from each position laterally separated from the irradiation position of the irradiation unit, but received here The light intensity at each point reflects the amount of the absorbing substance in the portion sandwiched between the light receiving portion and the linear irradiation portion.

Therefore, the intensity distribution of each point of the re-emitted light can be measured by the irradiating unit for irradiating the slit or linear light and the detecting unit for detecting the reflected light two-dimensionally. Further, the distribution of the magnitude of the absorption coefficient and the spatial distribution of the detected substance can be obtained by using the relationship between the intensity gradient of the re-emitted light in the distance direction and the absolute value of the absorption coefficient of the substance. When the detection target is hemoglobin, the distribution of the oxygen state can be obtained using a plurality of wavelengths. Further, the measurement result of each distribution can be imaged.

In an embodiment of the diffuse reflected light measuring apparatus according to the present invention, a light-shielding portion is provided on a side portion of the irradiation portion from the irradiation position in a side direction, and re-emission of the diffused light is blocked by the light-shielding portion.
The separation distance between the position of the reflected light detected by the detection unit and the irradiation position can be defined.

In an embodiment of the diffuse reflection light measuring apparatus according to the present invention, the irradiating section is constituted by arranging a plurality of irradiating members for irradiating slit-shaped light or arranging the irradiating members for irradiating linear light in a plane. With this configuration, it is possible to cope with a wide range of two-dimensional distribution measurement.

[0027]

Embodiments of the present invention will be described below in detail with reference to the drawings. With respect to a configuration example of an embodiment of the present invention, a configuration example that obtains an optimum detection sensitivity according to the material characteristics of a subject will be described with reference to FIGS. 1 to 4. A configuration example for obtaining a dimensional distribution will be described.

The configuration example shown in FIGS. 1 and 2 is a first configuration example in which an optimum detection sensitivity is obtained in accordance with the substance characteristics of the specimen.
FIG. 1 is a schematic configuration diagram for explaining a diffuse reflection light measuring device of the present invention, and FIG. 2 is a plan view and a cross-sectional view as viewed from above. The first configuration example of the diffuse reflection light measurement device includes an irradiation unit 1 that irradiates light into the sample s, and a detection unit 2 that detects reflected light diffused and re-emitted in the irradiation s. The irradiating section 1 includes an optical fiber 3 including an irradiating portion 11 configured to leak light from a side surface toward a sample, and a light source 4 is connected to one end of the optical fiber 3. The light source 4 supplies monochromatic light, and can be constituted by a laser light source or a monochromator having a spectroscope 5.

The light-irradiated portion of the optical fiber 3 has a length in the axial direction, thereby forming a slit-like or linear light and bringing the portion into close contact with the sample s. Light vertically (downward in Figure 1)
Irradiate.

Further, a light-shielding portion 12 is provided on a side portion along the axial direction of the irradiation portion 1 in a side direction from the irradiation position. The light shielding unit 12 shields part of the scattered light re-emitted from the sample s, thereby selecting reflected light to be detected by the detector and reflected light not to be detected. That is, the reflected light re-emitted from the irradiation position within the width of the light shielding unit 12 is shielded, and the light shielding unit 1 is blocked.
Only the reflected light re-emitted from outside the width of 2 is detected by the detection unit. Therefore, the width of the light shielding portion 12 in the lateral direction from the irradiation position defines the separation distance between the irradiation position and the detection position.

The detector 2 is a photodetector 2 for detecting the intensity of light.
1 and is arranged above the irradiation unit 1. This detector is
When the light intensity distribution is not required, a photodetector that does not have positional resolution and outputs only the intensity of the received light, such as the photodetector 21 in FIG. 1, can be used.

When monochromatic light is transmitted from the light sources 4 and 5 to the irradiation unit 1 through the optical fiber 3, the transmitted light is perpendicularly incident from the irradiation surface of the optical fiber constituting the irradiation unit 1 toward the sample s. . The light incident on the sample s is
Is scattered by the substance contained in the sample s, and as shown in FIG.
Is re-emitted from the surface. Here, since the light-shielding part 12 is provided on the side of the irradiation part 1, the reflected light re-emitted from the surface of the sample s emits light as shown in FIGS. Only from the outer part 6 of. The detector 2
The light intensity of the reflected light re-emitted from the outer portion of the light shielding unit 12 is detected.

Since the light absorption coefficient differs depending on the substance,
The absorption sensitivity detected also differs depending on the substance. Light shielding part 12
, The absorption sensitivity can be adjusted according to the substance to be measured. The adjustment of the absorption sensitivity corresponds to the adjustment of the optical path length in the light absorption analysis. In addition, the width of the light-shielding portion 2 can be, for example, about 1 to 10 mm.

For example, the change in absorption of glucose in the living body in the near-infrared region is very small, and the change in absorbance is very small. In such a measurement, if the optical path length is increased by increasing the width of the light shielding portion, the change in absorbance increases, and the actual detection ability can be improved.

The configuration example shown in FIGS. 3 and 4 is a second configuration example in which an optimum detection sensitivity is obtained in accordance with the substance characteristics of the specimen.
FIG. 3 is a schematic configuration diagram for explaining the diffuse reflection light measuring device of the present invention, and FIG. 4 is a plan view and a cross-sectional view as viewed from above. The second configuration example of the diffuse reflection light measurement device includes an irradiation unit 1 that irradiates light into the sample s, and a detection unit 2 that detects reflected light diffused and re-emitted in the irradiation s. The irradiating unit 1 is a light transmitting prism 13 configured to leak light from a side surface, and a light source 4 (not shown) via an optical fiber 3.
Connect. The light source 4 supplies monochromatic light as in the case of the first configuration example, and includes a laser light source or a spectroscope 5.
Can be constituted by a monochromator provided with.

The light-irradiated portion of the light-sending prism 13 has a surface having a predetermined width and a length in the axial direction. The surface is used as an irradiation surface to form slit-like light, and this portion is applied to the sample s. Then, the sample s is irradiated with light perpendicular to the axial direction.

The detecting section 2 includes a light receiving prism 22 and a light detector 23 for detecting light intensity, and is disposed above the irradiation section 1. The light receiving surface of the light receiving prism 22 has the same length as the light irradiating portion of the light transmitting prism 13 and is arranged in parallel with a predetermined distance from the light irradiating portion. The detector 23 detects the light intensity of the light incident on the light receiving prism 22, and may be a photodetector having no positional resolution and outputting only the intensity of the received light. The arrangement interval between the light-sending prism 13 and the light-receiving prism 22 defines the separation distance between the irradiation position and the detection position.

When monochromatic light is transmitted from a light source (not shown) to the irradiation unit 1 through the optical fiber 3, the transmitted light is perpendicularly incident from the irradiation surface of the light transmission prism 13 of the irradiation unit 1 toward the sample s. . The light incident on the sample s is
Is scattered by the substance contained in the sample s, and as shown in FIG.
Is re-emitted from the surface. Here, since the light-sending prism 13 and the light-receiving prism 22 are arranged at an interval, the reflected light re-emitted from the surface of the sample s is as shown in FIG.
This is the portion indicated by 6 in (a). The detector 2 detects the light intensity of the light incident on the light receiving prism 22 from the reflected light.

The absorption sensitivity can be adjusted according to the substance to be measured by the distance between the light transmitting prism 13 and the light receiving prism 22. Similarly to the first configuration, the adjustment of the absorption sensitivity corresponds to the adjustment of the optical path length in the light absorption analysis, and the arrangement interval between the light transmitting prism 13 and the light receiving prism 22 is, for example, about 1 to 10 mm. it can.

The optimum absorption sensitivity can be selected by adjusting the distance between the light transmitting prism 13 and the light receiving prism 22 according to the absorption coefficient of the target substance.

According to the second configuration, since only the light incident on the light receiving prism 22 is detected, a light-shielding portion is not required.
Further, the selection of the absorption sensitivity can be performed by adjusting only the arrangement interval.

Next, an example of a configuration for obtaining a two-dimensional distribution over a wide range of the diffuse reflection light measuring device of the present invention will be described. The configuration examples shown in FIGS. 5 and 6 are a first configuration example for obtaining a wide-area two-dimensional distribution, and FIG. 5 is a first configuration example for obtaining a wide-area two-dimensional distribution (hereinafter, the diffuse reflection light measurement of the present invention). FIG. 6 is a plan view and a detection intensity diagram as viewed from above. The third configuration example of the diffuse reflection light measurement device includes an irradiation unit 1 that irradiates light into the sample s, and a detection unit 2 that detects reflected light diffused and re-emitted in the irradiation s. The irradiating unit 1 is configured by arranging a plurality of irradiating members by the optical fiber shown in the first configuration example or by the light transmitting prism shown in the second configuration example. The irradiation unit 1 arranges irradiation members 14a to 14d made of an optical fiber or a prism configured such that light leaks from the side surface at intervals, and connects a light source to each end via the optical fibers 3a to 3d.
The light source can be the same as in the above configuration example.

Slit or linear light is emitted from the irradiation members 14a to 14d, and the sample s is irradiated with light vertically by bringing the irradiation unit 1 into close contact with the sample s. By using the plurality of irradiation members 14a to 14d, it is possible to irradiate light over a wide range of the sample s,
Extensive analysis can be performed.

In each of the irradiation members 14a to 14d, the separation distance between the irradiation position and the detection position is defined by the width of the light shielding portion or the arrangement interval of the light transmitting prism.

The detection unit 2 is a photodetector 21 having a position resolution and detecting a light intensity distribution, and is arranged above the irradiation unit 1.

When monochromatic light is transmitted from a light source (not shown) to the irradiation unit 1 through the optical fibers 3a to 3d in the optical fiber bundle 31, the transmitted light is transmitted to the irradiation units 14a to 14d.
The light is incident vertically (downward in the figure) from the irradiation surface of d toward the sample s. Therefore, this irradiation method is 14a to 14d
By arranging a large number of linear irradiation parts as shown in FIG.
It becomes an irradiation unit in a dimensional arrangement. The light incident on the sample s is scattered by the substance contained in the sample s, and has an intensity and a position corresponding to the absorption coefficient of the substance, as shown in FIGS. 6A and 6B.
It is re-emitted from the surface of the sample s again. The vertical axis in (b) indicates the intensity of light emitted from each position. The detector 21 can two-dimensionally detect the light intensity of the reflected light together with its position, and obtain a light intensity distribution. In addition, as shown in FIG. 6B, at the position where each of the irradiation units 14a to 14d exists,
No light detection is performed and the light intensity becomes zero.

In this configuration, the absorption sensitivity can be adjusted in accordance with the substance to be measured by adjusting the distance between the irradiation sections. This adjustment of the absorption sensitivity corresponds to the adjustment of the optical path length in light absorption analysis. I do. In addition, the width of the light-shielding portion 2 can be, for example, about 1 to 10 mm.

The configuration examples shown in FIGS. 7 and 8 are the second and third configuration examples for obtaining a two-dimensional distribution over a wide range (hereinafter, the fourth and fifth configuration examples of the diffuse reflection light measuring apparatus of the present invention). is there. Hereinafter, the outlines of the irradiation units of the fourth and fifth configuration examples will be described. Note that the detector of the fourth configuration example is the same as the third configuration example of the diffuse reflection light measuring device of the present invention, and thus the description is omitted. In FIG. 7, the irradiation unit 1 of the fourth configuration example of the diffuse reflection light measurement device is configured such that one optical fiber 3 having a light shielding unit 15 is formed in a planar shape and is arranged in contact with the sample s. Light is transmitted from both ends of the optical fiber 3 to irradiate light in a planar manner.

In FIG. 8, the irradiating section 1 and the detecting section 2 of the fifth example of the configuration of the diffuse reflection light measuring device are composed of a plurality of irradiating members 17a to 17d and a plurality of light receiving members 26a to 26e.
Are alternately arranged, and the light receiving members 26a to 26e
Places the end face of the optical fiber perpendicular to the sample s. The irradiation members 17a to 17d have optical fibers 3a to 3d.
d and transmits the reflected light to the optical fibers 25a to 25a.
Detect at the end of e. Irradiation unit 1 and detection unit 2 are sample s
And irradiates the light in a planar manner from the irradiation members 16a to 16d by transmitting light from the optical fibers 3a to 3d,
Light is received by the optical fibers 25a to 25e of the light receiving member. By determining the arrangement positions of the optical fibers 25a to 25e in advance, distribution measurement can be performed.

The distribution measurement by the two-dimensional detector is performed as a first-order measurement quantity, based on the intensity distribution, based on the relationship between the gradient of the light intensity in the distance direction and the absolute value of the absorption coefficient. The distribution of the coefficients, the spatial distribution of the target substance in the detection target, and in the case of hemoglobin, the distribution of the oxygen state can be calculated and displayed.

FIG. 9 shows an irradiation unit 1 and a detection unit 2 of a sixth example of the configuration of a diffuse reflection light measurement apparatus to which a configuration for obtaining an optimum detection sensitivity in accordance with the material properties of a subject is widely applied.
Are a plurality of irradiation members 16a to 16d and a plurality of light receiving members 2
The optical fibers 3a to 3d and the optical fibers 25a to 25d are arranged alternately.
By e, light is transmitted and received. The irradiation unit 1 and the detection unit 2 are arranged in contact with the sample s, and the optical fibers 3 a to 3
Light is emitted from the irradiation members 16a to 16d in a planar manner by transmitting light from the light source d, and measurement over a wide range can be performed by the light receiving members 24a to 24e.

[0052]

As described above, according to the diffuse reflection light measuring apparatus of the present invention, it is possible to obtain an optimum detection sensitivity in accordance with the material characteristics of the subject, and to obtain a wide range of light absorbing substances. Dimension information can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram for explaining a first configuration example for obtaining an optimum detection sensitivity according to a substance characteristic of an object of a diffuse reflection light measurement device of the present invention.

FIG. 2 is a plan view and a cross-sectional view of a first configuration example of the diffuse reflection light measuring device of the present invention.

FIG. 3 is a schematic configuration diagram for explaining a second configuration example for obtaining an optimum detection sensitivity in accordance with a substance characteristic of a subject in the diffuse reflection light measurement device of the present invention.

FIG. 4 is a plan view and a cross-sectional view of a second configuration example of the diffuse reflection light measuring device of the present invention.

FIG. 5 is a schematic configuration diagram for explaining a third configuration example for obtaining a wide-range two-dimensional distribution of the diffuse reflection light measurement device of the present invention.

FIG. 6 is a plan view and a detection intensity diagram of a third configuration example of the diffuse reflection light measuring device of the present invention.

FIG. 7 is a schematic configuration diagram for explaining a fourth configuration example for obtaining a two-dimensional distribution over a wide range of the diffuse reflection light measurement device of the present invention.

FIG. 8 is a schematic configuration diagram for explaining a fifth configuration example for obtaining a wide-range two-dimensional distribution of the diffuse reflection light measurement device of the present invention.

FIG. 9 is a schematic configuration diagram for explaining a sixth configuration example for obtaining an optimum detection sensitivity according to the material characteristics of the subject in the diffuse reflection light measurement device of the present invention.

FIG. 10 is an explanatory diagram illustrating a conventional measurement method.

FIG. 11 is an explanatory diagram showing a relationship between absorption sensitivity and optical signal intensity.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Irradiation part, 2 ... Detection part, 3, 3a-3d, 25a-2
5e: optical fiber, 4: light source, 5: spectroscope, 11: irradiation part, 12, 15: light shielding part, 13: light transmitting prism, 1
4a to 14d, 16a to 16d, 17a to 17d: irradiation member, 21, 23: detector, 22: light receiving prism, 24
a to 24e: light receiving member, 31: optical fiber bundle.

Claims (2)

[Claims] 1. An irradiation unit for irradiating a sample with slit or linear light, and a reflected light diffused in the sample and re-emitted from a position laterally separated from an irradiation position of the irradiation unit. A diffuse reflection light measuring device, comprising: a detection unit; wherein the separation distance is determined according to the intensity of reflected light detected by the detection unit and the light absorption characteristics of a detection substance contained in a sample. 2. An irradiation unit for irradiating a sample with slit or linear light, and a detection unit for two-dimensionally detecting reflected light re-emitted from a position laterally separated from an irradiation position of the irradiation unit. A diffuse reflection light measuring device comprising: obtaining a distribution of a detection substance contained in a sample from an intensity of reflected light detected by the detection unit and a two-dimensional position.