JPH10148611A - Light-measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve an efficient layout with a simple mechanism and to determine and correct the origin of time base without decreasing the amount of application light by providing a plurality of light-transmitting/receiving means that is formed by closely arranging optical fibers for transmitting light and optical fibers, for receiving light. SOLUTION: Light transmission and reception means Sp, Sq, and Sr where one end face of installed at a specimen 2 include optical fibers Ip, Iq, and Ir for transmitting light and optical fibers Op, Oq, and or for receiving light, respectively. Then, a light pulse is transmitted to the optical fiber Ip for transmitting light of the light-transmitting/receiving means Sp and is applied to the specimen 23 from an end face. The applied light is transmitted or scattered in the specimen 2 and advances. Light advancing the inside of the specimen 2 partially advance the inside of the optical fiber from the end face of the light-transmitting/receiving means Sr and the optical fiber Or for receiving light. The advancing light passes through the optical fiber Or for receiving light, is transmitted to a signal-processing means, and performs signal processing, thus obtaining data corresponding to the installation conditions of, for example, a distance between the light-transmitting/receiving means Sp and Sr.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light measuring apparatus for irradiating a subject with light, such as an optical CT or an 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 oxygen monitors are examples of measuring devices that apply such an optical measuring device to a living body. The subject can be any object that can transmit and scatter light such as visible light and near-infrared light, and can be applied to animals, plants, fruits and vegetables, as well as living organisms.

A light measuring device such as an optical CT or the like includes a plurality of light transmitting means and a plurality of light receiving means arranged around a subject, irradiates the inside of the subject with measurement light from one light transmitting means, and transmits the inside of the subject. Alternatively, the scattered light is received by the light receiving means. The light transmitting means for irradiating the measurement light is moved around the subject, and a large number of measurement data is measured by receiving the light with a plurality of light receiving means. A tomographic image inside the subject can be obtained based on the measurement data.

FIG. 10 is a view for explaining the arrangement of a light transmitting means and a light receiving means of a conventional light measuring device. In FIG. 10, light transmitting ends I1 to In of an optical fiber are arranged around the subject 2 as light transmitters, and light receiving ends O1 to On are provided between the light transmitting ends.
Are arranged and configured. The measuring light is sequentially transmitted from the optical fiber at the light transmitting end by the light transmitting pulse, and all the light receiving ends O1
ＯOn are simultaneously received by the optical fibers to obtain n light receiving signals. By performing the above steps sequentially while switching the light transmitting end, a total of n ² light receiving signals are measured, and a tomographic image of the subject can be calculated and obtained based on these signals.
In the light measuring device, since the light is strongly scattered, the light transmitting point of the light transmitting means and the light receiving point of the light receiving means need to be brought into close contact with the subject.

[0005] In the measurement of an object by an optical measurement device, it is known that pulse light is applied to the inside of the object and time-resolved measurement of light scattered in the object is performed. This optical time-resolved measurement measures the time required for scattered light to pass through the subject. In this measurement, the point in time at which the pulse light is applied to the subject is specified, and the time axis origin of the measurement is determined. It is necessary to determine.

Conventionally, as a general method for determining the origin of the time axis, as shown in FIG. 11, a light transmitting fiber for guiding a pulse light and a light receiving fiber for guiding a detection light to a light detection mechanism are joined to directly irradiate the irradiation pulse light. There is known a method in which a point at which a signal intensity obtained by measurement by a light detection mechanism reaches a peak value is set as an origin of a time axis. FIG. 12 shows the time distribution of the signal intensity of the light detection mechanism. In FIG. 12, the generation time of the pulse signal at the light source is set to time 0, and the point P where the signal intensity of the pulse light at the light detection mechanism reaches its peak value is set as the origin of the time axis. The time axis origin P is after the time T from the generation of the pulse signal due to the light transmission time or the like. Conventionally, the origin of the time axis of the optical measurement device is determined by arranging the transmitting and receiving fibers against each other and using the above-described determination method.

In general, a mechanism for generating pulse light and a mechanism for transmitting light are susceptible to the external environment, and are provided between a pulse signal for driving a light detection mechanism and generated pulse light, and between generated pulse light and irradiation. Between the light at the point
A temporal variation may occur, and the origin of the time axis of the measured time-resolved waveform may be shifted. If the deviation of the origin of the time axis occurs during the measurement, an error occurs in the determination of the optical constant of the subject and the image formation of the subject.

Therefore, conventionally, a mechanism for directly detecting the pulse light from the light source has been used to monitor and correct the deviation of the origin of the time axis while measuring the subject. FIG. 13 is a diagram for explaining a conventional mechanism for monitoring and correcting the deviation of the origin of the time axis. In FIG. 13, the light source 5 and the photodetector 6 are connected to the fiber F with respect to the optical measurement device including the light source 5, the transmission fiber I, the light reception fiber O, and the photodetector 6.
To form a monitoring and correction mechanism. FIG. 14 is a light intensity distribution diagram for explaining monitoring and correction of the deviation of the time axis origin. FIG. 14A shows the light intensity immediately after the determination of the time axis origin, and FIG. 14B shows the light intensity at the point in time after the determination of the time axis origin. By measuring the time difference dT at the peak of the light intensity, the shift of the origin of the time axis is monitored and corrected.

[0009]

As described above, it is necessary to arrange a large number of light transmitting means and light receiving means side by side around the subject, and it is difficult to efficiently arrange them in a narrow place. In addition, there is a problem that handling of the light transmitting and receiving means becomes difficult. Further, there is a first problem that the installation density of the light transmitting and receiving means cannot be easily increased.

As shown in FIG. 10, in order to obtain n 2 measurement data for the subject 2, a total of 2n optical fibers are provided around the subject 2 by combining a light transmitting optical fiber and a light receiving optical fiber. Need to be placed.
Further, even when the size of the subject 2 changes, it is necessary to devise a configuration so that the mutual arrangement of the optical fibers does not change.

Further, the conventional optical measuring device requires a mechanism for determining and correcting the origin of the time axis, and has a second problem that the amount of light irradiated on the subject is reduced.

In the time-resolved measurement of the optical measuring device, a light transmitting fiber and a light receiving fiber are attached to a subject, respectively. In order to determine and correct the origin of the time axis, the light transmitting fiber is required as shown in FIG. And a light receiving fiber are required. FIG.
In order to determine the origin of the time axis in a device having a large number of transmitting and receiving fibers, such as an optical tomographic imaging device (optical CT) as shown in FIG. It is necessary to perform at least the same number of operations as the number of detectors for determination and correction, and it takes much time and effort to set the configuration shown in FIG.

In order to correct the origin of the time axis, if an optical fiber branching mechanism as shown in FIG. 13 is used,
In addition to the necessity of a branching mechanism, the light from the light source is branched and the amount of irradiation light is reduced.

SUMMARY OF THE INVENTION Accordingly, it is a first object of the present invention to solve the above-mentioned problems of the conventional light measuring device and to provide a light measuring device capable of performing efficient arrangement, and to irradiate the light with a simple mechanism. It is a second object of the present invention to provide a light measuring device capable of determining and correcting the origin of the time axis without reducing the light quantity.

[0015]

According to a first aspect of the present invention, there is provided a light measuring apparatus for transmitting light to a subject and receiving light from the subject to optically measure the subject. This is a measuring device, wherein a light transmitting and receiving means is formed by arranging a light transmitting optical fiber and a light receiving optical fiber close to each other, and a plurality of the light transmitting and receiving means are provided. Thus, the number of light transmitting and receiving means provided in the light measuring device can be reduced, and efficient arrangement can be performed.

According to the light measuring device of the first invention of the present application, light is sent through the light transmitting optical fiber of the one light transmitting / receiving means, and light is irradiated into the subject from the end of the light transmitting optical fiber. The light radiated into the subject is transmitted or scattered in the subject, and then received from the end of the receiving optical fiber of the same transmitting / receiving unit or a different transmitting / receiving unit, and transmitted to the signal processing unit through the receiving optical fiber. Can be

Therefore, the light transmitting and receiving means of the light measuring device according to the first invention of the present application includes the light transmitting means and the light receiving means close to each other,
In order to transmit and receive the light of the light transmitting unit and the light receiving unit in the proximity state, the light transmission and the reception are performed by separate optical fibers, respectively, as in a conventional optical measurement device, so that the irradiation of the light to the subject and the The number of light transmitting and receiving means including optical fibers can be reduced as compared with the method of individually receiving light from the light source, and efficient arrangement can be performed to increase the arrangement density of the light transmitting and receiving means.

Further, the light measuring device of the second invention of the present application is a light measuring device for optically measuring a subject by transmitting light to the subject and receiving light from the subject. A pulse light generating means for generating pulse light, a light detecting means for time-resolved measurement of light from the subject, and an integrated light transmitting and receiving means including a light transmitting optical fiber and a light receiving optical fiber. Thus, the origin of the time axis can be obtained from the time-resolved waveform of the light transmission / reception by the light transmission / reception means.

According to the optical measuring device of the second invention of the present application, the subject is irradiated with the pulse light generated by the pulse light generating means by the light transmitting optical fiber of the light transmitting and receiving means, and is scattered by the subject. The reflected light is received by the light receiving optical fiber of the light transmitting and receiving means, and the light from the subject is time-resolved and measured by the light detecting means. In the light transmitting and receiving means, since the light transmitting optical fiber and the light receiving optical fiber are arranged close to each other, the light receiving optical fiber receives light reflected from the vicinity of the irradiation point. The reflected light from a distance close to the irradiation point of the subject is not so affected by the optical constants of the subject, and a time-resolved waveform of almost the same shape can be obtained. Decisions and corrections can be made.

An optical tomographic imaging apparatus (light C) in which a plurality of light transmitting fibers and light receiving fibers are arranged around a subject.
In T), the object is illuminated using one of the light-transmitting fibers, and simultaneously detected by a plurality of light-receiving fibers, while the time detected by the light-receiving fiber arranged close to the light-transmitting point among the light-receiving points. Using the decomposition waveform, it is possible to determine the origin of the time axis of the time-resolved measurement, monitor the deviation, and correct the deviation.

The optical tomographic imaging apparatus can change the position of the irradiation point and perform measurement by sequentially switching the light transmission fiber to be irradiated.

According to a first embodiment of the present invention, the light transmitting / receiving means for the light transmitting optical fiber and the light receiving optical fiber arranged in close proximity is formed by an integrated optical fiber bundle including the light transmitting optical fiber and the light receiving optical fiber. It is.

In a second embodiment of the present invention, a pair of optical fibers for transmitting and receiving light and an optical fiber for receiving light are formed in a double concentric cylindrical shape. Optical fiber for light transmission
The outer optical fiber can be a receiving optical fiber. According to this configuration, when the light transmitting / receiving unit rotates, the rotation center of the light transmitting / receiving unit is set to the center of the optical fiber pair, so that the fluctuation of the light transmitting point and the light receiving point due to the rotation can be eliminated.

A third embodiment of the present invention is directed to a double concentric cylinder as a multi-component bundle fiber in which a light transmitting optical fiber is a single core fiber and a light receiving optical fiber is provided around the single core fiber via a mold. It is formed in a shape.

Further, in a fourth embodiment of the present invention, the light radiated into the subject from the light transmitting / receiving optical fiber of the light transmitting / receiving means is received by the light receiving / receiving optical fibers of different light transmitting / receiving means, so that the measurement signal is obtained. The reference time origin can be set.

[0026]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic block diagram for explaining an embodiment of the light measuring device of the present invention. In FIG. 1, the optical measurement device 1 includes a plurality of light transmitting / receiving means S, and the light transmitting / receiving means S is arranged around the subject 2 to perform measurement. The light transmitting / receiving means S is a light transmitting optical fiber I
And an optical fiber bundle including a light receiving optical fiber O, and one end of each optical fiber is a light transmitting end face and a light receiving end face. A light emitting means and a signal processing means are provided on the other end (not shown) of the optical fiber bundle. A known light-emitting device such as a light-emitting diode can be used as the light-emitting means, and the signal processing means uses an electric signal converted by the light-electric signal conversion means, and performs measurement signal processing for measuring time between transmitted and received light, Various signal processing such as arithmetic processing for obtaining a tomographic image can be performed. In addition, signal processing such as selection of light transmitting / receiving means for transmitting light in the light emitting device, control of the order of light transmission, and correction of the time origin in signal processing,
This can be performed in the signal processing means.

FIG. 1 shows an example in which n transmitting / receiving means S from S1 to Sn are provided.

FIG. 2 is a schematic diagram for explaining the operation of the light transmitting / receiving means S, and includes three light transmitting / receiving means Sp, Sq, Sr.
Is set on the subject 2. Each of the light transmitting / receiving means Sp, Sq, Sr is a light transmitting optical fiber Ip,
It includes Iq, Ir and optical fibers Op, Oq, Or for light reception, and one end face thereof is placed on the subject 2. The light pulse is sent to the light transmitting optical fiber Ip of the light sending / receiving means Sp, and the object 2 is irradiated from the end face. The irradiated light is transmitted or scattered in the subject 2 and proceeds. A part of the light traveling inside the subject 2 is received by the light receiving optical fiber Or of the light transmitting / receiving means Sr.
From the end face of the optical fiber. The entered light is sent to a signal processing means (not shown) through a light receiving optical fiber Or to perform signal processing to obtain data according to installation conditions such as a distance between the light sending / receiving means Sp and the light sending / receiving means Sr. be able to.

FIG. 2 shows an example in which the light irradiated from the light transmitting / receiving optical fiber Ip of the light transmitting / receiving means Sp is received by the light receiving optical fiber Or of the light transmitting / receiving means Sr, but the light transmitting / receiving means Sq or Sr Can be transmitted from the optical fiber O. Also, the light receiving optical fiber O of the light transmitting / receiving means Sq can be used.
The light can be received by q. When signal processing is performed with the received light to obtain measurement data, the measurement data is processed in consideration of the installation relationship such as the distance between the light transmission and reception of the light transmission and reception unit and the installation position.

When n light transmitting / receiving means S1 to Sn are provided around the subject 2 as shown in FIG. 1, for example, light is transmitted from the light transmitting optical fiber Ik of one light transmitting / receiving means Sk. The light transmitted through the subject 2 is received by the light receiving optical fibers O1 to On of the light transmitting and receiving means S1 to Sn, and the light is measured to obtain measurement data. The processing step of performing a measurement by receiving sending from this single beam transmitting and receiving means Sk by a plurality of beam transmitting and receiving unit S1 to Sn, by performing while switching beam transmitting and receiving means Sk for performing sending ^two n in total Measurement data can be obtained.

In the configuration example of FIG. 1, in order to obtain n ² measurement data, the optical measuring apparatus of the present invention uses n transmitting / receiving means, whereas the conventional optical measuring apparatus shown in FIG. In the light measuring device, n light transmitting means and n light receiving means total 2
It requires n light transmitting and receiving means. Therefore, according to the optical measuring device of the present invention, the number of light transmitting / receiving means can be reduced.

FIG. 3 is a view for explaining an embodiment of an optical fiber used for the light measuring device of the present invention. In FIG. 3, the optical fiber 3 constituting the light transmitting and receiving means is formed by forming a pair of optical fibers of a light transmitting optical fiber 3a and a light receiving optical fiber 3b in a double concentric cylindrical shape. An optical fiber may be used, and the outer optical fiber 3b may be used as a light receiving optical fiber.

The light transmitting optical fiber 3a may be, for example, a single-core quartz fiber, and the light-receiving optical fiber 3b may be, for example, a multi-component bundle fiber. By providing the multi-component bundle fiber in the above, it is possible to form a double concentric cylindrical shape.

Usually, the light transmitting side uses light guided from a light emitting means such as a laser, so that a thin fiber such as a single-core fiber is used, and the light receiving side receives a large amount of diffused light. It is effective to use a component bundle fiber. It is to be noted that both the light transmission and the light reception can be configured by bundle fibers, and in this case, the inside can be configured to receive light and the outside can be configured to transmit light.

FIG. 4 is a view for explaining an example of a configuration using the light measuring device of the present invention, and is an example in which a ring-shaped belt is configured. In FIG. 4B, the light measuring device 10 is a ring-shaped belt. A pair of adjacent pieces 10a and 10
b is crossed in an X-shape, and one end of the optical fiber 3 of the light transmitting / receiving means is attached to the center of the X-shape so that the end face faces the subject 2. Further, a unit in which the X-shaped units are successively connected by pins 10c so as to be movable is formed. With this configuration, when a ring-shaped belt is attached around the subject 2 as shown in FIG. 4A, the pair of pieces 10a and 10b change the angular relationship between the two according to the outer diameter of the subject 2. This allows the entire ring to expand and contract, so that the end face of the optical fiber of the light transmitting and receiving means can be brought into contact with the subject 2. Since the cylindrical optical fiber can rotate about the axis, the optical fiber is not twisted.

Since the optical fiber used in the optical measuring device of the present invention has a structure in which the light transmitting means and the light receiving means are provided in one place, even if the optical fiber is rotated, the light is transmitted and received according to the installation position of the light transmitting and receiving means. It is possible to reduce a change in the amount of light and light received.

In particular, when the optical fiber is configured as shown in FIG. 3, the center of rotation of the light transmitting and receiving means is set to the center of the pair of optical fibers, so that the positional relationship between the light transmitting means and the light receiving means is the same, and the transmission by rotation is performed. Fluctuations in the light spot and the light receiving point can be eliminated, and the handling of the support and the fiber becomes easy. If the fiber cannot rotate,
Fibers may be twisted or broken or broken by rotational stress.

FIG. 5 is a diagram for explaining another configuration example using the light measuring device of the present invention.
An example is shown in which the surface is measured in a two-dimensional manner. In FIG. 5, the light measuring device 11 has a planar base 11a.
A plurality of optical fibers 3 are arranged on one side of the base 11a, and the end faces of the optical fibers 3 are set so as to face the subject 2 from the other side of the base 11a.

At the other end of the optical fiber, light emitting means and signal processing means (not shown) are provided. When the optical fiber having the configuration shown in FIG. 3 is used, the light transmitting optical fibers arranged on the center side of the optical fiber are collected, and FIG.
A light transmitting pulse is transmitted from the light emitting means provided on the side 11b to one of the light transmitting optical fibers. In addition, optical fibers for light reception arranged on the outer peripheral side of the optical fiber are collected, and FIG.
The received light is sent to a signal processing means provided on the side 11c.

A well-known light-emitting device such as a light-emitting diode can be used as the light-emitting means. A light-to-electric signal conversion means for converting light into an electric signal and a time measurement between light transmission and reception light can be used for the signal processing means. Processing means for performing various signal processing such as the measurement signal processing described above and the arithmetic processing for obtaining a tomographic image can be arranged.

Next, the measurement in the light measuring device of the present invention will be described with reference to FIG. In the light measuring device, in order to irradiate the subject with light, one of the plurality of light transmitting / receiving means is selected from among a plurality of light transmitting / receiving means, and FIGS.
As shown in (c), this is carried out by sending a light pulse to the one light sending / receiving means through the light sending optical fiber I1. On the other hand, as shown in FIGS. 6 (a) to 6 (c), the light that has traveled through the subject is converted from light incident on one of the light-receiving end faces of the plurality of light-receiving means into light-receiving optical fibers O1, O2, O2, and O2. Or O
By sending it to the signal processing means through 3.

In a normal measurement performed by the light measuring device, FIG.
As shown in (b) and (c), the light passing through the subject is
The light is received by the optical fiber of the light transmitting / receiving means different from the light transmitting / receiving means for transmitting the light. For example, in FIG. 6B, the light pulse incident from the light transmitting optical fiber I1 is received by the light receiving optical fiber O2 of the different light transmitting and receiving means, and FIG.
Then, the light pulse incident from the light transmitting optical fiber I1 is received by the light receiving optical fiber O3 of the different light transmitting / receiving means. The time response of the light received by the light-receiving optical fiber O2 by the time-resolved photometry has, for example, a waveform shown by a broken line in FIG.
The time response of the light received at 3 has a waveform, for example, as shown by the dashed line in FIG.

The waveform of the light received by each light receiving means changes according to the distance between the light transmitting optical fiber and the light receiving optical fiber, the characteristics of the subject, and the temperature change of the light source. For example, in a light source that generates pulsed light, a temporal change occurs between a pulse signal for driving a pulsed light generation mechanism and the generated pulsed light due to an environmental change such as a temperature change.

In the time-resolved photometry, measurement is performed by determining the time difference between received light. However, a large number of optical fibers are transmitted through an optical fiber due to a difference in length between the light emitting means and the end of the light transmitting / receiving means. Differences in light transmission time,
Due to the time variation between the pulse signal and the pulse light, it is necessary to monitor and correct the origin of the time axis.

Therefore, as shown in FIG. 6 (a), when light is transmitted and received between the same light transmitting and receiving means, the incident point and the emitting point are extremely close to each other. Can be ignored. Therefore, it is possible to correct the reference of the time for transmitting light in the living body by defining the peak time of the time-resolved waveform when transmitting and receiving light between the same transmitting and receiving means as the zero point of time. In other words, even if there is a time difference between different transmitting and receiving means due to the difference in the length of the fiber, it can be easily corrected by this method. The extra operation to be determined can be omitted.

Next, using FIGS. 7 and 8 and Tables 1 and 2,
The operation of obtaining the time base origin from the time-resolved waveform using the present invention will be described. FIG. 7 is a simulation configuration diagram,
FIG. 8 and Tables 1 and 2 show the simulation results.

In FIG. 7, the simulation for obtaining the origin of the time axis from the time-resolved waveform is based on the assumption that the light transmitting unit 21 and the light receiving unit 22 are arranged at an interval of the distance d between the light transmission and reception by infinity in the lateral and depth directions. It is placed on the subject 20 which approximates a flat plate, light is incident at point incidence, and reflected light is detected by a circle having a diameter of 1 mm.

In this simulation, when the interval d between the light transmitting and receiving points is 2 mm, the absorption coefficient μa is set to 0.
Table 1 shows the time (pSec) at which the light intensity peaks when the scattering coefficient is changed from 00 / mm to 0.02 / mm and the scattering coefficient μs ′ is changed from 0.50 / mm to 1.5 / mm.
Shown in In addition, in the scattering coefficient μs ′, 0.50 / m
The range of m to 1.5 / mm is generally a value that a living body can take.

[0049]

[Table 1] According to the simulation results shown in Table 1, the time when the light intensity reaches a peak is almost constant.

FIG. 8 shows the scattering coefficient μs'1.00 / m
The simulation result in the case of m is shown. Here, the vertical axis represents the normalized light amount.

In the simulation, when the distance d between the light transmitting and receiving points is 3 mm, the absorption coefficient μa is changed from 0.00 / mm to 0.02 / mm.
Table 2 shows the time (pSec) at which the light intensity peaks when the scattering coefficient μs ′ is changed from 0.50 / mm to 1.5 / mm.

[0052]

[Table 2] Therefore, according to the simulation result, when the interval d between the light transmitting and receiving points is about 2 to 3 mm, the error is several pSe.
c and 2.5 in the distance accuracy of the transmitting and receiving points.
For an accuracy of ± 0.5 mm, it is about ± 6 pSec.

Therefore, according to the present invention, the light transmitting and receiving fibers are attached to a subject such as a living body or a simulated living body without forming an optical system for abutting the light transmitting and receiving fibers. By measuring the time-resolved waveform when irradiated at
The origin of the time axis can be determined.

During the measurement of the subject,
The generated pulse light generation mechanism and the shift of the time axis of the optical fiber can be calculated from the time-resolved waveform that detects the reflected light at a distance close to the irradiation point and the time axis obtained by determining the time-axis origin. Therefore, using this time axis shift,
The time axis of the time-resolved waveform measured by another photodetector can be corrected.

FIG. 9 is a view for explaining another embodiment of the optical fiber used for the light measuring device of the present invention.
In FIG. 9, an optical fiber 4 constituting a light transmitting / receiving means is shown.
Comprises a plurality of light transmitting optical fibers 4a and light receiving optical fibers 4b dispersedly arranged.
5 can also be applied to the embodiment shown in FIG. In the case of this configuration, the shape of the optical fiber 4 can be set to an arbitrary shape, and a light transmitting point and a light receiving point having a spread can be formed.

According to the embodiment of the present invention, the time axis can be determined without abutting the transmitting and receiving fibers.

According to the embodiment of the present invention, the time axis deviation of the pulse light generating mechanism can be monitored and corrected without branching the irradiated pulse light.

[0058]

As described above, according to the light measuring apparatus of the present invention, efficient arrangement can be performed, and the time axis origin can be determined and reduced by a simple mechanism without lowering the irradiation light quantity. Corrections can be made.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram for explaining an embodiment of a light measuring device according to the present invention.

FIG. 2 is a schematic diagram for explaining the operation of the light transmitting / receiving means of the present invention.

FIG. 3 is a diagram illustrating an embodiment of an optical fiber used in the optical measurement device of the present invention.

FIG. 4 is a diagram illustrating an example of a configuration using the optical measurement device of the present invention.

FIG. 5 is a diagram illustrating another configuration example using the optical measurement device of the present invention.

FIG. 6 is a diagram illustrating measurement by the optical measurement device of the present invention.

FIG. 7 is a simulation configuration diagram for explaining an operation of obtaining a time base origin from a time-resolved waveform using the present invention.

FIG. 8 is a simulation result for explaining an operation of obtaining a time base origin from a time-resolved waveform using the present invention.

FIG. 9 is a diagram illustrating another embodiment of the optical fiber used for the light measuring device of the present invention.

FIG. 10 is a diagram illustrating an arrangement of a light transmitting unit and a light receiving unit of a conventional light measuring device.

FIG. 11 is a configuration diagram for explaining a general method of determining a time axis origin.

FIG. 12 is a diagram illustrating a time distribution of signal intensity of the light detection mechanism.

FIG. 13 is a diagram for explaining a conventional mechanism for monitoring and correcting the deviation of the origin of the time axis.

FIG. 14 is a light intensity distribution diagram for explaining monitoring and correction of a deviation of a time axis origin.

FIG. 15 is a diagram for explaining an optical tomographic imaging apparatus (optical CT).

[Explanation of symbols]

Reference numerals 1, 10, 11: optical measuring device, 2: subject, 3, 4: optical fiber, 20: subject, 21: light transmitting unit, 22: light receiving unit, S1, S2, -Sn, light transmitting and receiving means I1, I2 , ~ In: Optical fiber for transmitting light, O1, O2, -On: Optical fiber for receiving light.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Ichiro Oda 380-1 Matsuba, Horiyamashita, Hadano-shi, Kanagawa Inside the Hadano Plant of Shimadzu Corporation

Claims (2)

[Claims] 1. An optical measuring device for transmitting light to a subject and optically measuring the subject by receiving light from the subject, wherein an optical fiber for transmitting light and an optical fiber for receiving light are arranged close to each other. An optical measurement device, comprising: a light transmitting / receiving means; and a plurality of the light transmitting / receiving means. 2. A light measuring apparatus for optically measuring a subject by transmitting light to the subject and receiving light from the subject, wherein a pulse light generating means for generating pulsed light; Light detection means for time-resolved measurement of light from
An optical measurement device comprising: an integrated light transmitting and receiving means including a light transmitting and receiving optical fiber and a light receiving and receiving optical fiber; and obtaining a time axis origin from a time-resolved waveform of the light transmitting and receiving by the integrated light transmitting and receiving means.