JP2020159978A - Spectroscopic measuring device and spectroscopic measuring method - Google Patents

Abstract

To provide practical technology with which spectroscopic measurement can be carried out at high speed with sufficient accuracy over a wide wavelength band.SOLUTION: The wideband pulse light emitted from a pulse light source 1 has its pulse width stretched with a fiber 20 as an extension element 2 and thereafter divided into a long wavelength-side light and short wavelength-side light by a dichroic mirror 32 before being irradiated onto an object S. Light from the object S having been irradiated with the long wavelength-side light is received by a first optical receiver 41 and light from the object S having been irradiated with the short wavelength-side light is received by a second optical receiver 42. Output data from the optical receivers 41, 42 are inputted to computation means 5 via an AD converter 7 and then processed by a measurement program 53, and a spectroscopic spectrum is calculated.SELECTED DRAWING: Figure 8

Description

The invention of this application relates to a technique for spectroscopic measurement.

The spectroscopic measurement technique of irradiating an object with light and measuring the spectrum of the light (transmitted light, reflected light, scattered light, etc.) from the object is typical as a technique for analyzing the composition and properties of the object. It is a thing. A typical spectroscopic measurement method is a method using a diffraction grating. The light to be measured incident from the incident slit is made into parallel light by a concave mirror and irradiated to the diffraction grating, the dispersed light from the diffraction grating is similarly condensed by the concave mirror, and a receiver is placed at the condensing position for detection. By changing (scanning) the attitude of the diffraction grating, light of different wavelengths is sequentially incident on the receiver, and the output of the receiver becomes a spectrum.

In spectroscopic measurement using such a diffraction grating, high-speed measurement cannot be performed because a scan of the diffraction grating is required. Further, since the light is limited in the incident slit, the SN ratio of the measurement cannot be increased. Therefore, it is necessary to repeat the scan several times to increase the total amount of light (light amount) incident on the receiver, which is also a factor that prevents high-speed measurement.

In recent years, a multi-channel spectroscope using an area sensor in which a large number of photoelectric conversion elements are arranged in a row has been developed. In the case of the multi-channel type, scanning of the diffraction grating is unnecessary, so high speed can be expected. However, since the basic structure of limiting the light with the incident slit and irradiating the diffraction grating with the concave mirror remains the same, the problem of a small SN ratio is not solved, and the drawback of lengthening the measurement time to increase the amount of light is solved. Not.

Japanese Unexamined Patent Publication No. 2013-205390

On the other hand, in the field of light source technology, research on widening the wavelength of pulsed light emitted from a pulsed light source is being actively conducted. A typical pulsed light source is a pulsed laser (pulse laser). In particular, when an ultrashort pulse laser beam is passed through a non-linear element such as a fiber, the band is widened by a non-linear optical effect such as self-phase modulation. This light is called supercontinuum light (hereinafter referred to as SC light).

Broadband pulsed light, such as SC light, is extended in wavelength range but remains narrow in pulse width (time width). However, if an appropriate transmission delay difference is generated between the wavelengths, the pulse width can also be extended. For example, when broadband pulsed light is passed through a fiber having an appropriate group delay characteristic such as a distributed compensation fiber (DCF), the pulse width is extended due to the transmission delay difference between wavelengths. When an element having an appropriate wavelength dispersion characteristic is selected at the time of pulse extension, the pulse can be extended in a state where the elapsed time (time) in the pulse and the wavelength have a one-to-one correspondence.

The correspondence between the elapsed time and the wavelength in the wideband pulsed light (hereinafter referred to as wideband stretched pulsed light) pulse-stretched in this way can be effectively used for spectroscopic measurement. That is, when a wideband extended pulsed light is received by a certain receiver, the temporal change in the light intensity detected by the receiver corresponds to the light intensity of each wavelength, that is, the spectrum. Therefore, the temporal change of the output data of the receiver can be converted into a spectrum, and spectroscopic measurement can be performed without using a special dispersion element such as a diffraction grating. That is, the spectral characteristics (for example, spectral transmittance) of the sample can be known by irradiating the sample with wideband extended pulsed light, receiving the light from the sample with a receiver, and measuring the temporal change thereof. Will be.

However, according to the research of the inventor, in reality, there is a problem of the characteristics of the element that performs pulse elongation and a problem of the characteristics of the receiver that detects the wideband extended pulse light, which is a practical problem when considering the entire spectroscopic measurement system. Exists.
The invention of this application has been made to solve the above-mentioned problems when the wideband extended pulsed light is used for spectroscopic measurement, and is practical in that spectroscopic measurement can be performed at high speed with sufficient accuracy over a wide wavelength band. The purpose is to provide various technologies.

In order to solve the above problems, the invention of the spectroscopic measuring apparatus of the present application includes a pulse light source that emits wideband pulsed light and a pulse light source.
An extension element that extends the pulse width of wideband pulsed light from a pulse light source so that the relationship between the elapsed time and wavelength in the pulse is 1: 1.
A dividing element that divides the wideband pulsed light whose pulse width is extended by the expanding element into two,
The first receiver that receives the light from the object irradiated with one of the light divided by the dividing element, and
A second receiver that receives light from the object irradiated with the other light divided by the dividing element, and
It is equipped with a calculation means for converting the temporal change of the output from the first receiver and the temporal change of the output from the second receiver into a spectrum.
The first and second receivers have a configuration in which the spectral sensitivity characteristics are different from each other.
Further, in this spectroscopic measurement device, the first receiver is a receiver having a higher spectral sensitivity than the second receiver in the first wavelength range, and the second receiver has the first wavelength range. Is a receiver with higher spectral sensitivity than the first receiver in a different second wavelength range, and the computing means spectrum the temporal change in the output from the first receiver for the first wavelength range. The second wavelength range may have a configuration of being a means for converting the temporal change of the output from the second receiver into a spectrum.
Further, in order to solve the above problems, the invention of the spectroscopic measuring apparatus of the present application includes a pulse light source that emits wideband pulsed light and a pulse light source.
An extension element that extends the pulse width of wideband pulsed light from a pulse light source so that the relationship between the elapsed time and wavelength in the pulse is 1: 1.
A dividing element that divides wideband pulsed light whose pulse width is extended by the extending element into a long wavelength and a short wavelength with the dividing wavelength as a boundary.
The first receiver that receives the light from the object irradiated with the long wavelength light divided by the dividing element, and
A second receiver that receives light from an object irradiated with light of a shorter wavelength that is divided by a dividing element, and
It is configured to include a calculation means for converting a temporal change in the output from the first receiver and a temporal change in the output from the second receiver into a spectrum.
Further, in order to solve the above problems, the invention of the spectroscopic measuring apparatus of the present application includes a pulse light source that emits wideband pulsed light and a pulse light source.
A dividing element that divides the wideband pulsed light emitted from the pulse light source into a long wavelength and a short wavelength with the dividing wavelength as a boundary.
A first extension element that extends the pulse width so that the relationship between the elapsed time in the pulse and the wavelength is 1: 1 for the light of the longer wavelength divided by the dividing element.
A second extending element that extends the pulse width so that the relationship between the elapsed time in the pulse and the wavelength is 1: 1 for the light of the shorter wavelength divided by the dividing element.
The first receiver that receives the light from the object irradiated with the light whose pulse width is extended by the first extension element, and
A second receiver that receives light from an object irradiated with light whose pulse width is extended by the second extension element, and
It is configured to include a calculation means for converting a temporal change in the output from the first receiver and a temporal change in the output from the second receiver into a spectrum.
Further, in order to solve the above problems, the spectroscopic measuring apparatus of the present application includes a pulse light source that emits wideband pulsed light and a pulse light source.
An extension element that extends the pulse width of wideband pulsed light from a pulse light source so that the relationship between the elapsed time and wavelength in the pulse is 1: 1.
A dividing element that divides the light from an object irradiated with wideband pulsed light extended by the expanding element into two, and a dividing element.
The first receiver that receives one of the light divided by the dividing element, and
A second receiver that receives the other light divided by the dividing element, and
It is equipped with a calculation means for converting the temporal change of the output from the first receiver and the temporal change of the output from the second receiver into a spectrum.
The first and second receivers have a configuration in which the spectral sensitivity characteristics are different from each other.
Further, in this spectroscopic measurement device, the first receiver is a receiver having a higher spectral sensitivity than the second receiver in the first wavelength range, and the second receiver has the first wavelength range. Is a receiver with higher spectral sensitivity than the first receiver in a different second wavelength range, and the computing means spectrum the temporal change in the output from the first receiver for the first wavelength range. The second wavelength range may have a configuration of being a means for converting the temporal change of the output from the second receiver into a spectrum.
Further, in order to solve the above problems, the spectroscopic measuring apparatus of the present application includes a pulse light source that emits wideband pulsed light and a pulse light source.
An extension element that extends the pulse width of wideband pulsed light from a pulse light source so that the relationship between the elapsed time and wavelength in the pulse is 1: 1.
A dividing element that divides the light from an object irradiated with wideband pulsed light extended by the stretching element into a long wavelength and a short wavelength with the dividing wavelength as a boundary.
The first receiver that receives the long wavelength light divided by the dividing element, and
A second receiver that receives light of the shorter wavelength divided by the dividing element, and
It is configured to include a calculation means for converting a temporal change in the output from the first receiver and a temporal change in the output from the second receiver into a spectrum.
Further, in order to solve the above problems, the spectroscopic measurement method of the present application includes an emission step of emitting a broadband pulsed light from a pulse light source.
A pulse extension step in which the pulse width of the wideband pulsed light emitted in the emission step is extended by an extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1.
In the pulse extension step, the wideband pulsed light whose pulse width is extended is divided into two by a dividing element, and the dividing step.
In the first light receiving step, in which the light from the object irradiated with one of the light divided in the dividing step is received by the first light receiver,
In the second light receiving step, in which the light from the object irradiated with the light of the other wavelength divided in the dividing step is received by the second light receiver,
Calculation of the temporal change of the output from the first receiver received in the first light receiving step and the temporal change of the output from the second receiver received in the second light receiving step into a spectrum by an arithmetic means. It has a process and
The first and second receivers have a configuration in which the spectral sensitivity characteristics are different from each other.
Further, in this spectroscopic measurement method, the first receiver is a receiver having a higher spectral sensitivity than the second receiver in the first wavelength range, and the second receiver has the first wavelength range. Is a receiver with higher spectral sensitivity than the first receiver in a different second wavelength range.
In the calculation process, the temporal change of the output from the first receiver is converted into a spectrum for the first wavelength range, and the temporal change of the output from the second receiver is spectrumd for the second wavelength range. It can have a configuration that it is a process of converting to.
Further, in order to solve the above problems, the spectroscopic measurement method of the present application includes an emission step of emitting a broadband pulsed light from a pulse light source.
A pulse extension step in which the pulse width of the wideband pulsed light emitted in the emission step is extended by an extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1.
In the pulse extension step, the wideband pulsed light whose pulse width is extended is divided into long wavelengths and short wavelengths with the division wavelength as a boundary by a dividing element.
In the first light receiving step, in which the light from the object irradiated with the long wavelength light divided in the dividing step is received by the first light receiver,
In the second light receiving step, in which the light from the object irradiated with the light of the shorter wavelength divided in the dividing step is received by the second light receiver,
Calculation of the temporal change of the output from the first receiver received in the first light receiving step and the temporal change of the output from the second receiver received in the second light receiving step into a spectrum by an arithmetic means. It has a configuration that includes a process.
Further, in order to solve the above problems, the spectroscopic measurement method of the present application includes an emission step of emitting a broadband pulsed light from a pulse light source.
A dividing element that divides the wideband pulsed light emitted in the emission process into a long wavelength and a short wavelength with the dividing wavelength as a boundary.
The first pulse extension step in which the pulse is extended by the first extension element so that the relationship between the elapsed time in the pulse and the wavelength is 1: 1 for the light having a long wavelength among the broadband pulsed light divided in the division step. When,
A second pulse extension step in which the pulse is extended by the second extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1 for the light having the shorter wavelength divided in the division step.
In the first pulse extension step, the first light receiving step of receiving the light from the object irradiated with the pulse-stretched light by the first receiver, and
In the second pulse extension step, the second light receiving step of receiving the light from the object irradiated with the pulsed extended light by the second receiver, and
An arithmetic means for converting the temporal change of the output from the first receiver received in the first light receiving step and the temporal change of the output from the second receiver received in the second light receiving step into a spectrum. It has a configuration of being equipped.
Further, in order to solve the above problems, the invention of the spectroscopic measurement method of the present application includes an emission step of emitting a broadband pulsed light from a pulse light source.
A pulse extension step in which the pulse width of the wideband pulsed light emitted in the emission step is extended by an extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1.
In the pulse extension step, the split step of splitting the light from the object irradiated with the broadband pulsed light whose pulse width is stretched into two by the split element,
In the first light receiving step, in which one of the light divided in the dividing step is received by the first light receiver,
In the second light receiving step, in which the other light divided in the dividing step is received by the second light receiver,
Calculation of the temporal change of the output from the first receiver received in the first light receiving step and the temporal change of the output from the second receiver received in the second light receiving step into a spectrum by an arithmetic means. It has a process and
The first and second receivers have a configuration in which the spectral sensitivity characteristics are different from each other.
Further, in this spectroscopic measurement method, the first receiver is a receiver having a higher spectral sensitivity than the second receiver in the first wavelength range, and the second receiver has the first wavelength range. Is a receiver with higher spectral sensitivity than the first receiver in a different second wavelength range.
In the calculation process, the temporal change of the output from the first receiver is converted into a spectrum for the first wavelength range, and the temporal change of the output from the second receiver is spectrumd for the second wavelength range. It can have a configuration that it is a process of converting to.
Further, in order to solve the above problems, the invention of the spectroscopic measurement method of the present application includes an emission step of emitting a broadband pulsed light from a pulse light source.
An extension step in which the pulse width of the wideband pulsed light emitted in the emission step is pulse-extended by an extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1.
In the stretching step, the splitting step of dividing the light from the object irradiated with the stretched broadband pulsed light into a long wavelength and a short wavelength with the splitting wavelength as a boundary by a splitting element,
In the first light receiving step, in which one of the light divided in the dividing step is received by the first light receiver,
In the second light receiving step, in which the other light divided in the dividing step is received by the second light receiver,
The calculation step of converting the temporal change of the output from the first receiver received in the first light receiving step and the temporal change of the output from the second receiver received in the second light receiving step into a spectrum. It has a configuration of being equipped.
Further, in order to solve the above problems, the spectroscopic measurement method of the present application includes a first emission step of emitting a broadband pulsed light from a pulse light source and a first emission step.
In the first pulse extension step, the pulse width of the broadband pulsed light emitted in the first emission step is extended by the extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1.
In the first pulse extension step, the first irradiation step of irradiating the object with the pulse-stretched broadband pulsed light, and
In the first light receiving step, in which the light from the object irradiated in the first irradiation step is received by the first light receiver,
A second emission step of emitting another broadband pulsed light from a pulsed light source,
A second pulse extension step in which the pulse width of the broadband pulsed light emitted in the second emission step is extended by an extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1.
In the second pulse extension step, the second irradiation step of irradiating the object with the pulse-extended broadband pulsed light, and
In the second light receiving step, the light from the object irradiated in the second irradiation step is received by the second light receiving device having different spectral sensitivity characteristics from the first light receiving device.
Calculation of the temporal change of the output from the first receiver received in the first light receiving step and the temporal change of the output from the second receiver received in the second light receiving step into a spectrum by an arithmetic means. It has a configuration that includes a process.
In each of the above configurations, the extension element can be single-mode fiber, single-mode multi-core fiber, single-mode fiber bundle fiber, multimode fiber, diffraction grating, chirped fiber Bragg grating or prism.
In each of the above configurations, the first extension element and the second extension element may be elements having different extension characteristics from each other.
In each of the above configurations, the dividing element can be any of a dichroic mirror, a wavelength dividing multiplex coupler, a diffraction grating, and an array waveguide grating.
In each of the above configurations, the pulse light source can be a supercontinuum light source.
In each of the above configurations, the pulse light source can be a supercontinuum light source that outputs continuous light over a wavelength width of at least 10 nm in a wavelength range of 900 nm or more and 1300 nm or less.
In each of the above configurations, the first receiver may be an InGaAs photodiode receiver.
In each of the above configurations, the second receiver can be a Si photodiode receiver.
In each of the above configurations, the spectroscopic measuring device sets the position where the object is irradiated with one of the light divided by the dividing element or the light having a long wavelength, and the other light or the short of the divided elements. It may be provided with a moving mechanism that moves it to and from a position where light of a wavelength is irradiated.
In each of the above configurations, the spectroscopic measuring device irradiates the object with the light whose pulse width is extended by the first stretching element and the light whose pulse width is extended by the second stretching element. It may be provided with a moving mechanism for moving to and from a position.

As described below, according to the spectroscopic measuring device or the spectroscopic measuring method of the present application, in the spectroscopic measurement utilizing the time wavelength uniqueness of the pulse-stretched wideband pulsed light, the measurement is divided into two detection systems. The detection of light in each wavelength range can be optimized according to the characteristics of the stretching element and the characteristics of the receiver. Therefore, spectroscopic measurement can be performed at high speed with sufficient accuracy over a wide wavelength band.
Further, according to the spectroscopic measurement device or the spectroscopic measurement method of the present application, in the spectroscopic measurement utilizing the time wavelength uniqueness of the pulse-extended broadband pulsed light, the measurement is divided into two detection systems according to the wavelength range. The detection of light in each wavelength range can be optimized according to the characteristics of the stretching element and the characteristics of the receiver. Therefore, spectroscopic measurement can be performed at high speed with sufficient accuracy over a wide wavelength band.
Further, in a configuration in which the wideband pulsed light is subjected to pulse elongation after the dividing element divides the wavelength, if the first and second stretching elements have different stretching characteristics, the pulse stretching can be optimized according to the wavelength range. it can.
In addition, according to a device or method that divides the light from the object into two and measures it with two detection systems, the structure is simpler and the measurement accuracy is improved even if the reproducibility of the wideband pulsed light is reduced. The effect that it does not decrease can be obtained.
Further, if the pulse light source is a supercontinuum light source that outputs continuous light over a wavelength width of at least 10 nm in the wavelength range of 900 nm or more and 1300 nm or less, it is particularly suitable for spectroscopic analysis of solid-phase or liquid-phase objects. It will be meaningful.

It is the schematic of the spectroscopic measurement apparatus of 1st Embodiment. It is the schematic which showed the principle of the pulse extension of a wide band pulsed light. It is the schematic which showed an example of the spectral sensitivity characteristic of each receiver. It is a figure which showed the transmission characteristic of a certain fiber used as an extension element. It is the schematic which showed the data which a measurement program handles. It is a flowchart which showed the schematic diagram of the measurement program. It is the schematic of the spectroscopic measurement apparatus of the 2nd Embodiment. It is a schematic diagram of the spectroscopic measurement apparatus of the third embodiment. It is the schematic of the spectroscopic measurement apparatus of 4th Embodiment. It is the schematic of the spectroscopic measurement apparatus of the 5th Embodiment. It is the schematic which showed the example of another division element. It is a schematic diagram of the spectroscopic measurement apparatus of the sixth embodiment. It is the schematic of the spectroscopic measurement apparatus of 7th Embodiment. It is the schematic of the spectroscopic measurement apparatus of 8th Embodiment. It is the schematic which showed the other example of the extension element.

Hereinafter, embodiments (embodiments) for carrying out the invention of this application will be described.
FIG. 1 is a schematic view of the spectroscopic measuring device of the first embodiment. The spectroscopic measurement device shown in FIG. 1 is a device that irradiates an object S with pulsed light for spectroscopic measurement, and as described above, irradiates pulsed light having a one-to-one relationship between time and wavelength in the pulse. It is a device for spectroscopic measurement.
Specifically, the spectroscopic device shown in FIG. 1 includes a pulse light source 1 that emits wideband pulsed light, an extension element 2 that extends the pulse width of the wideband pulsed light from the pulse light source 1, and a pulse whose pulse width is extended. An operation to calculate a spectrum according to an irradiation optical system 3 that irradiates an object S with light, receivers 41 and 42 that receive light from the object S irradiated with pulsed light, and outputs from the receivers 41 and 42. It is provided with means 5.

In this embodiment, the pulse light source 1 emits SC light. The pulse light source 1 which is an SC light source includes an ultrashort pulse laser source 11 and a non-linear element 12.
A gain switch laser, a microchip laser, a fiber laser, or the like can be used as the ultrashort pulse laser source 11. Further, as the nonlinear element 12, a fiber is often used. For example, a photonic crystal fiber or other non-linear fiber can be used as the non-linear element 12. The fiber mode is often a single mode, but it can be used as the non-linear element 12 as long as it exhibits sufficient non-linearity even in the multi-mode.

The wavelength range of the wideband pulsed light is not particularly limited. The SC light can have a continuous spectrum over a very wide wavelength range of, for example, about 500 to 2000 nm, and may be a pulsed light having a wide band to this extent. A pulse light source 1 that is not so wide and emits pulsed light having a wide band within a required range may be used. For example, in the case of spectroscopic measurement in the near infrared region, a light source that emits pulsed light having a continuous spectrum over at least 10 nm, 50 nm, or 100 nm in the range of about 900 to 1300 nm can be used as the pulse light source 1.
As the extension element 2, a single mode fiber 20 is used in this embodiment. For example, a fiber having a predetermined group delay characteristic as used as a dispersion compensation fiber (DCF) in the optical communication field can be used as the extension element 2.

FIG. 2 is a schematic view showing the principle of pulse elongation of wideband pulsed light. As a means for extending the pulse width of wideband pulsed light such as SC light, for example, when SC light L1 having a continuous spectrum in a certain wavelength range is passed through a fiber 20 having a positive dispersion characteristic in the wavelength range, the pulse width is increased. Is effectively stretched. That is, as shown in FIG. 2, in the SC light L1, although it is an ultra-short pulse, light having the longest wavelength λ ₁ exists at the beginning of one pulse, and light having a gradually shorter wavelength exists over time. However, at the end of the pulse, there is light with the shortest wavelength λ _n . When this light is passed through the normally dispersed fiber 20, the light having a shorter wavelength propagates later in the normally dispersed fiber 20, so that the time difference within one pulse is increased, and when the light is emitted from the fiber 20, it is shorter. Wavelength light will be further delayed compared to long wavelength light. As a result, the emitted SC light L2 becomes light whose pulse width is extended while the uniqueness of time vs. wavelength is ensured. That is, as shown on the lower side of FIG. 2, the times t _{1 to} t _n are pulse-extended in a state of having a one-to-one correspondence with each of the wavelengths λ _{1 to} λ _n .

It is also possible to use an abnormal dispersion fiber as the fiber 20 for pulse extension. In this case, in the SC light, the light on the long wavelength side that existed at the beginning of the pulse is delayed, and the light on the short wavelength side that existed at a later time is dispersed in a state of advancing, so that the time within one pulse The target relationship is reversed, and the light on the short wavelength side exists at the beginning of one pulse, and the pulse is extended in a state where the light on the longer wavelength side exists with the passage of time. However, as compared with the case of normal dispersion, it is often necessary to lengthen the propagation distance for pulse extension, and the loss tends to be large. Therefore, normal dispersion is preferable in this respect.

The irradiation optical system 3 includes a beam expander 30 in this embodiment. Although the light from the fiber 20 as the extending element 2 is a time-extended wideband pulsed light, it is light from an ultrashort pulse laser source 11, and the beam diameter is small. In addition, a scanning mechanism such as a galvano mirror may be provided to cover a wide irradiation area by beam scanning.

In this embodiment, it is assumed that the absorption spectrum of the object S is measured, and therefore the receivers 41 and 42 are provided at positions where the transmitted light from the object S is incident. The receiving plates 61 and 62 are provided at the irradiation positions of the broadband pulsed light by the irradiation optical system 3. The receiving plates 61 and 62 are transparent in the measurement wavelength range. The object S is placed on the receiving plates 61 and 26. The irradiation optical system 3 is adapted to irradiate light from above, and the receivers 41 and 42 are located on the exit side (lower in this example) of the receiving plates 61 and 62.

As the calculation means 5, a general-purpose personal computer is used in this embodiment. An AD converter 7 is provided between the light receivers 41 and 42 and the calculation means 5, and the output of the receivers 41 and 42 is digitized by the AD converter 7 and input to the calculation means.
The calculation means 5 includes a processor 51 and a storage unit (hard disk, memory, etc.) 52. A measurement program 53 that processes output data from the receivers 41 and 42 to calculate a spectrum and other necessary programs are installed in the storage unit 52.

In the spectroscopic measurement apparatus of such an embodiment, the entire spectroscopic measurement system is optimized in consideration of the characteristics of the extension element 2 and the characteristics of the photoreceivers 41 and 42. Specifically, the spectroscopic measurement system in the apparatus of the embodiment is a system in which wideband pulsed light is divided into two and each is detected individually, and two different detection systems, first and second, are provided. ..

More specifically, as shown in FIG. 1, the irradiation optical system 3 includes a dividing element. As the dividing element, the beam splitter 31 is used in this embodiment. The beam splitter 31 is a half-split mirror, and is an element that splits into 1/2 light flux.
Since the beam splitter 31 as a dividing element is arranged, the optical path from the extending element 2 branches into a first optical path P1 and a second optical path P2, as shown in FIG. The receiving plates 61 and 62 are provided on the respective optical paths P1 and P2, respectively, and the receivers 41 and 42 are arranged on the exit side of the receiving plates 61 and 62, respectively.

In this embodiment, receivers 41 and 42 having different spectral sensitivity characteristics are adopted as constituents of different detection systems. That is, receivers 41 and 42 having different spectral sensitivity characteristics depending on the measurement wavelength range are used. Assuming that the receivers 41 and 42 are the first receiver 41 and the second receiver 42, the first receiver 41 has a higher spectral sensitivity than the second receiver 42 in the first wavelength range, and is the first. As the second receiver 42, one having a higher spectral sensitivity than the first receiver 41 in a second wavelength range different from the first wavelength range is used. As an example, an InGaAs diode receiver using an InGaAs diode as a light receiving cell can be used as the first receiver 41, and a Si diode receiver using a Si diode as a light receiving cell can be used as the second receiver 42. Can be used.

FIG. 3 is a schematic view showing an example of the spectral sensitivity characteristics of each receiver. Similarly, in the example of FIG. 3, the spectral sensitivity characteristics of the InGaAs diode receiver as the first receiver 41 and the spectral sensitivity characteristics of the Si diode receiver as the second receiver 42 are shown. As shown in FIG. 3, the InGaAs diode receiver has a good sensitivity in the range of about 1000 to 1700 nm, and the Si diode receiver has a good sensitivity in the range of about 500 to 1000 nm.

The spectroscopic measurement apparatus of the embodiment is provided with two different detection systems in this way because the transmission characteristics of the fiber used as the extension element 2 and the sensitivity characteristics of the receiver itself are taken into consideration. This point will be described below.
FIG. 4 is a diagram showing the transmission characteristics of a certain fiber used as the extension element 2. The fiber whose transmission characteristics are shown in FIG. 4 is a quartz-based single-mode fiber having positive dispersion characteristics. In FIG. 4, the horizontal axis represents the wavelength, and the vertical axis represents the attenuation rate (dB) per 1 km. As shown in FIG. 4, this fiber has a transmission characteristic in which the attenuation factor increases as the wavelength becomes shorter.

On the other hand, when it is used as the extension element 2 as in the embodiment, a certain length is required. This is because the gradient in time wavelength uniqueness (Δλ / Δt shown in FIG. 2) needs to be moderated to some extent. This is because if the gradient is steep, the wavelength resolution becomes low due to the relationship with the response speed (signal ejection cycle) of the receiver. In order to make the gradient Δλ / Δt gentle, it is necessary to increase the amount of elongation, and for that purpose, it is necessary to lengthen the fiber.

However, as can be seen from FIG. 4, if the fiber is lengthened, the light attenuation increases, and the amount of attenuation increases particularly on the short wavelength side. That is, if the fiber is lengthened in order to increase the wavelength resolution, the attenuation increases especially on the short wavelength side. As a result, even if the pulse light source 1 emits wideband pulsed light having flat intensity characteristics between wavelengths, the intensity balance between wavelengths is deteriorated due to the decrease in intensity in the short wavelength region after pulse extension. Can be.

Another problem is that it is difficult for the receiver to have uniform sensitivity characteristics for wideband light. For example, in the case of spectroscopic measurement in the near infrared region, an InGaAs diode receiver that employs InGaAs as a light receiving cell can be preferably used. However, when attempting spectroscopic measurement over a wide band from the visible region to the near infrared region, the InGaAs diode receiver does not have sufficient sensitivity in the short wavelength region of less than 900 nm, as shown in FIG.

In the spectroscopic measuring apparatus of the embodiment, in consideration of these, the detection system is divided into two wavelength bands, and the optimum receiver is used for each. That is, as described above, the InGaAs diode receiver is used as the first receiver 41 in the first wavelength range (long wavelength region), and the second receiver 42 in the second wavelength range (short wavelength region). A Si diode receiver is used as a device. As shown in FIG. 3, the Si diode receiver has good sensitivity in the short wavelength region up to about 1050 nm, and the intensity is reduced in the short wavelength region due to the attenuation in the fiber as the extension element 2. However, a sufficient photoelectric conversion output can be obtained, and spectroscopic measurement in this wavelength range can be performed without any trouble.

Next, the measurement program 53 implemented in the arithmetic means will be described. FIG. 5 is a schematic diagram showing the data handled by the measurement program 53, and FIG. 6 is a flowchart showing a schematic diagram of the measurement program 53.
The examples of FIGS. 5 and 6 are examples of a program in which the measurement program 53 measures the absorption spectrum (spectral absorption rate) as a spectral characteristic. As described above, the outputs from the receivers 41 and 42 are input to the calculation means 5 via the AD converter 7, respectively. This is a collection of data (photoelectric conversion values) for each signal payout cycle in each of the receivers 41 and 42, and is a data set. Hereinafter, the data set input from the first receiver 41 via the AD converter 7 is referred to as the first data set, and the data set input from the second receiver 42 via the AD converter 7 is the first data set. Let us be the second data set.
As described above, the first receiver 41 is for measurement in the first wavelength range, and the second receiver 42 is for measurement in the second wavelength range. Hereinafter, for convenience of explanation, the first wavelength range is λ ₁ to λ _m . Further, the second wavelength range is λ _{m + 1} to λ _n .

Reference spectrum data is used in the calculation of the absorption spectrum. The reference spectrum data is a value for each wavelength that serves as a reference for calculating the absorption spectrum. The reference spectrum data is acquired in advance by incidenting the wideband pulse extended light on the receivers 41 and 42 without passing through the object S. That is, the light is directly incident on the receivers 41 and 42 without passing through the object S, and the outputs of the receivers 41 and 42 are similarly input via the AD converters 7. Hereinafter, the data set input in this manner will be referred to as a first reference data set and a second reference data set. Each reference data set is recorded in a file, and each file is stored in the storage unit 52.

Each reference data set is the reference intensity of each time t ₁ , t ₂ , t ₃ , ... For each time resolution Δt (V ₁ , V ₂ , V ₃ , ...). The time resolution Δt is the response speed (signal payout cycle) of the detector 5, and is the time interval for outputting the signal. Hereinafter, the first reference data set is a reference data set for the first wavelength range, the reference intensity at time _{t 1 ~t m V 1, V} 2, V 3, ···, a _{V m.} A second reference data set, a reference data set for the second wavelength range, the time _{t m} + 1 reference intensity in _{~t n V m + 1, V} m + 2, V m + 3, ···, a _{V n.}

Regarding the first reference data set, the relationship between the time t ₁ , t ₂ , t ₃ , ..., T _m in one pulse and the wavelength has been investigated in advance, and the values V ₁ , V ₂ , V of each time have been investigated. ₃ , ..., V _m is treated as the light intensity at λ ₁ , λ ₂ , λ ₃ , ..., λ _m , respectively. The same applies to the second reference data set, and the values at each time in one pulse V _{m + 1} , V _{m + 2} , V _{m; 3} , ..., V _n are λ _{m + 1} , λ _{m + 2} , λ _{m + 3} , ...・, It is treated as the light intensity at λ _n .

As shown in FIG. 6, the measurement program 53 first acquires the first data set and the first reference data set from the files, respectively. Then, each measured value in the first data set is compared with each reference value in the first reference data set (v ₁ / V ₁ , v ₂ / V ₂ , v ₃ / V ₃ , ..., v _m / V _m ), and the result is temporarily stored in a variable (array variable).
Next, the measurement program 53 acquires the second data set and the second reference data set from the files, respectively. Then, each measurement value in the second data set is compared with each reference value in the second reference data set (vm _{+ 1} / V _{m + 1} , v _{m + 2} / V _{m + 2} , v _{m + 3} / V _{m + 3} , ... ·, V _n / V _n ), and the result is temporarily stored in another variable (array variable).

Next, the measurement program 53 acquires the calculation result from the variable, and the calculation result of the absorption spectrum S _A it as a a the calculation result successively. That is, v ₁ / V ₁ is the absorption rate at λ ₁ , v ₂ / V ₂ is the absorption rate at λ ₂ , and ... v _m / V _m is the absorption rate at λ _m . Further, v _{m + 1} / V _{m + 1} is defined as the absorption rate at λ _{m + 1} , v _{m + 2} / V _{m + 2} is defined as the absorption rate at λ _{m + 2} , and ... v _n / V _n is defined as the absorption rate at λ _n . If necessary, the logarithm of each reciprocal is taken as the absorption rate. Thus, the absorption rate i.e. absorption spectrum _{S A} in lambda ₁ to [lambda] _n is obtained. Measurement program 53 ends as a result of execution of the program and the resulting absorption spectrum S _A.

The operation of the spectroscopic measuring device of such an embodiment will be described below. The following description is also a description of the spectroscopic measurement method of the embodiment.
First, the object S is placed on the first receiving plate 61, and the pulse light source 1 is operated. In the pulse light source 1, the ultrashort pulsed light from the ultrashort pulsed laser source 11 is incident on the nonlinear element 12, widened by the nonlinear optical effect, and emitted as broadband pulsed light. The wideband pulsed light is incident on the stretching element 2, and the pulse width is stretched by the stretching element 2.

The pulsed light having an extended pulse width is split by a beam splitter 31 as a dividing element, one light travels along the first optical path P1 and the other light travels along the second optical path P2. The light traveling along the first optical path P1 irradiates the object S. Then, the light transmitted through the object S is incident on the first receiver 41. The output from the first receiver 41 is input to the calculation means 5 via the AD converter 7, temporarily recorded in a file, and stored in the storage unit 52.

Next, the operation of the pulse light source 1 is temporarily stopped, and the (same) object S (object S measured by the light traveling through the first optical path P1) is transferred to the second receiving plate 62. (For example, the measurer manually reprints it). In this state, the pulse light source 1 is operated again. Similarly, the broadband pulsed light is extended by the stretching element 2 and split by the beam splitter 31 as a splitting element. This time, the other light that has traveled through the second optical path P2 is applied to the object S, and the light that has passed through the object S is received by the second light receiver 42. The output of the second receiver 42 is input to the calculation means 5 via the AD converter 7. Then, similarly, it is temporarily recorded in a file and stored in the storage unit 52.
In this way, when the detection of the transmitted light by the two detection systems is completed, the measurement program 53 operates and the absorption spectrum is calculated as described above. The calculated absorption spectrum is appropriately displayed on a display or the like.

In the above operation, the output from the first receiver 41 includes values v _{m + 1 to} v _n from t _{m + 1 to} t _n , and the output from the second receiver 42 includes t ₁ to t _m. Values up to v _{1 to} v _m are included, but these are not included in the final measurement results. However, for the output data from the second receiver 42, it is necessary to specify the time of t ₁ (rise of the pulse) in order to specify the time of t _{m + 1} . In that part, the data of the time before t _{m + 1} is also used for the measurement. That is, the spectrum is obtained by using the time of t ₁ as a reference and assuming that the time when the time of t _{m + 1} has elapsed is the intensity of the wavelength of λ _{m + 1} . The same applies to λ _{m + 2 and} later.

According to the spectroscopic measurement device and the spectroscopic measurement method of such an embodiment, in the spectroscopic measurement utilizing the time wavelength uniqueness of the pulse-stretched wideband pulsed light, the spectroscopic measurement is divided into two detection systems. The detection of light in each wavelength range can be optimized according to the characteristics and the characteristics of the receivers 41 and 42. Therefore, a spectroscopic measuring device and a spectroscopic measuring method capable of performing spectroscopic measurement with sufficient accuracy and high speed over a wide wavelength band are provided.
In the above embodiment, a configuration divided into two detection systems is adopted, but it goes without saying that it may be divided into three or more detection systems.

Since the above operation and method are configured to selectively use one of the detection systems for measurement, it is preferable to adopt a configuration for canceling the measurement in the unselected detection system. For example, each of the receiving plates 61 and 62 is provided with a sensor for detecting whether or not the object S is mounted, and when the object S is not mounted, the output of the corresponding receivers 41 and 42 is There may be a configuration in which the calculation means 5 is not input (or is canceled even if it is input). Alternatively, a shutter may be appropriately provided in each detection system, and in a detection system that is not used, light may not be incident on the receivers 41 and 42 by the shutter.

In the above embodiment, the wavelength band of the broadband pulsed light from the pulse light source 1 and the total felt wavelength band of the two receivers 41 and 42 extend to the near infrared region of 900 to 1300 nm. This point has the meaning that the object S is a solid phase or a liquid phase and is suitable for analyzing the object S by absorption. Many materials have absorption wavelengths in the 900 to 1300 nm band, and it is particularly meaningful for spectroscopic analysis of the solid-phase or liquid-phase object S to cover this band widely by two detection systems. .. For example, the spectroscopic measuring device and the spectroscopic measuring method of the embodiment can be used for the analysis of a drug (tablet or the like).

In the above description, the spectroscopic measurement is performed by the wide band pulse light of one pulse emitted from the pulse light source 1, but in reality, the spectroscopic measurement is often performed by the wide band pulse light of a plurality of pulses. In this case, each of the above data sets is a plurality of data sets, and the spectrum is calculated by averaging the measured values of each data set.
Further, in the above example, the absorption spectrum is measured as a spectral characteristic, but other spectra such as a reflection spectrum and a scattering spectrum may be used. When measuring the reflection spectrum, the receivers 41 and 42 are arranged at positions where the reflected light from the object S is received, and when measuring the scattering spectrum, the receivers 41 and 42 are located at positions where the scattered light is received. Is placed.

Next, the spectroscopic measuring device and the spectroscopic measuring method of the second embodiment will be described. FIG. 7 is a schematic view of the spectroscopic measuring device of the second embodiment.
Also in the second embodiment, the first and second detection systems are provided. The second embodiment is different from the first embodiment in that the dividing element is provided on the optical path in front of the extending element, and as a result, the first and second two extending elements 21 and 22 are provided. That is the point. Also in this embodiment, the beam splitter 31 is used as the dividing element.

The incident end of the fiber (hereinafter, the first fiber) 210 as the first extension element 21 is arranged on the optical path P1 of one of the lights transmitted through the beam splitter 31, and the other light reflected by the beam splitter 31. The incident end of the fiber (hereinafter, the second fiber) 220 as the second extension element 22 is arranged on the optical path P2. The first receiving plate 61 is arranged at the irradiation position of the light emitted from the first fiber 210, and the second receiving plate 62 is arranged at the irradiation position of the light emitted from the second fiber 220. Further, as in the first embodiment, the first receiver 41 is arranged on the exit side of the first receiving plate 61, and the second receiver 42 is arranged on the emitting side of the second receiving plate 62. Has been done.

The difference between the first embodiment and the second embodiment is whether the light is wavelength-divided after pulse extension or pulse extension is performed before pulse extension, and the other parts are basically the same. is there. One of the lights transmitted through the beam splitter 31 as a splitting element is transmitted by the first fiber 210 to extend the pulse width, and then irradiates the object S. Then, the light transmitted through the object S is detected by the first receiver 41. Further, the other light reflected by the beam splitter 31 is transmitted by the second fiber 220 to extend the pulse width, and then irradiates the object S. Then, the light transmitted through the object S is detected by the second receiver 42. Then, the outputs from the light receivers 41 and 42 are input to the calculation means 5 via the AD converter 7, and the spectrum is calculated by the measurement program 53.

The configuration of the second embodiment can be said to be a configuration in which a pulse extension element is incorporated in each detection system. This configuration has the advantage that an optimum extension element can be adopted according to the characteristics of the detection system. That is, the pulse extension can be optimized as a whole by using the extension elements 21 and 22 having different dispersion characteristics to obtain a desired dispersion. For example, different group dispersion characteristics can be used for the first fiber 210 and the second fiber 220. Further, the first fiber 210 and the second fiber 220 having different lengths can be used.

To show a more preferable configuration, in the pulse extension shown in FIG. 2, it is desirable that the time-to-wavelength slope (Δλ / Δt) after the extension is constant over the entire wavelength range. This is because it becomes easier to correspond the time and the wavelength, and the calculation accuracy of the spectrum is improved. In this case, the fibers 210 and 220 used as the extension elements 21 and 22 often have different delay sizes depending on the wavelength even if they have the same positive dispersion. Therefore, a first detection system including the first receiver 41 for the purpose of measuring the first wavelength range and a second receiver 42 for the purpose of measuring the second wavelength range are provided. In the detection system of, pulse extension is performed with separate fibers, and the delay amount of each is optimized. As a result, Δλ / Δt after pulse extension can be made uniform as a whole. The configuration of the second embodiment is superior to the first embodiment in that such a thing becomes possible.
However, since two extension elements 2 are required, the cost is high in that respect. Conversely, the first embodiment in which pulse extension is performed and then wavelength division is performed is more cost effective.

Next, the third embodiment will be described. FIG. 8 is a schematic view of the spectroscopic measuring device of the third embodiment.
In the third embodiment, the dichroic mirror 32 is used as the split element instead of the beam splitter 31 in the configuration of the first embodiment. Other configurations are the same as in the first embodiment.
The dichroic mirror 32 is an element that divides light into two lights according to a wavelength. For example, as shown in FIG. 9, one that transmits light having a wavelength longer than the divided wavelength λc and transmits light having a wavelength shorter than λc is used. The first light receiver 41 is arranged on the first optical path P1 for long wavelengths, and the second light receiver 42 is arranged on the second optical path P2 for short wavelengths.

In this embodiment, since the light is divided by the dividing element according to the wavelength and the detection system is different for each wavelength range, the loss can be reduced when the detection system is optimized according to the wavelength range. In this respect, it is a more suitable spectroscopic measuring device. This point will be described below.
In the first embodiment, the light is split into two by the beam splitter 31 without splitting according to the wavelength, and is received by the first and second receivers 41 and 42 via the object S. Then, among the outputs from the first and second receivers 41 and 42, the wavelength range having higher spectral sensitivity is selected and converted into wavelength, which is used as the measurement result. In this configuration, the wavelength range with low spectral sensitivity is not used for measurement, and that amount is a loss in a sense.

On the other hand, in the third embodiment, since the dichroic mirror 32 that divides the light according to the wavelength is used as the dividing element, the divided wavelength λc is determined according to the spectral sensitivity characteristics of the first and second receivers 41 and 42. If is appropriately selected, there will be no loss when a wavelength range having a higher spectral sensitivity is selected and converted into a wavelength. Therefore, a spectroscopic measurement device and a spectroscopic measurement method capable of performing spectroscopic measurement with sufficient accuracy, high speed, and efficiency over a wide wavelength band are provided.

The split wavelength can be the boundary wavelength between the first wavelength range and the second wavelength range in the first embodiment. That is, when the InGaAs diode receiver and the Si diode receiver are used as described above, both have sensitivity in the range of about 900 to 1100 nm (the sensitive wavelength ranges overlap). Therefore, the division wavelength is selected within this range, and can be set to, for example, about 1050 nm. That is, the dichroic mirror 32 as the dividing element can be a mirror that transmits 1050 nm or more and reflects less than 1050 nm.

The configuration of the calculation means is basically the same as that of the first and second embodiments, but the processing of the output data from the second receiver 42 is slightly different. In the first and second embodiments, in the processing of the output data from the second receiver 42, t ₁ in the output data of the second receiver 42 is used to specify the time t _{m + 1} at the first wavelength λ _{m + 1.} It was based on the time of (pulse rise). In the third embodiment, the light having the wavelength of λ ₁ corresponding to t ₁ does not enter the second receiver 42. The light of the first wavelength incident on the second receiver 42 is the wavelength closest to λc among the light having an effect shorter than λc and an effective intensity (for example, an intensity of 5% or more with respect to the peak of the pulse). (Hereinafter referred to as the division reference wavelength). The time of the division reference wavelength becomes the reference time in the processing of the output data from the second receiver 42, and the intensity of light of each wavelength is acquired by the elapsed time for each Δt with respect to this. The division reference wavelength has been investigated in advance, and the time when the effective intensity of the output data from the second receiver 42 is first observed is set as the time of the division reference wavelength. After that, the intensity of each wavelength is set according to the correspondence relationship for each Δt.

Next, a fourth embodiment will be described. FIG. 9 is a schematic view of the spectroscopic measuring device of the fourth embodiment.
The spectroscopic measuring device of the fourth embodiment has a configuration in which the dichroic mirror 32 is used as the splitting element instead of the beam splitter 31 in the configuration of the second embodiment. Other configurations are the same as in the second embodiment.

Similarly, the dichroic mirror 32 is an element that divides wideband pulsed light into two light according to a wavelength, and as shown in FIG. 9, transmits light having a wavelength longer than the divided wavelength and a wavelength shorter than the divided wavelength. The one that transmits the light of is used. Then, the incident end of the first fiber 210 as the first extension element 21 is arranged on the first optical path P1 for the long wavelength, and the second extension is placed on the second optical path P2 for the short wavelength. The incident end of the second fiber 220 as the element 22 is arranged. Similarly, the first receiver 41 is arranged at a position where the light emitted from the first fiber 210 is received through the object S, and the light emitted from the second fiber 220 is received through the object S. A second light receiver 42 is arranged at a position where light is received.
Also in the fourth embodiment, since the light of λ ₁ does not enter the second receiver 42, the division reference wavelength is examined in advance as in the third embodiment, and it is effective first. It is assumed that the time when the intensity is observed is the division reference wavelength. After that, the intensity of light of each wavelength is acquired by the correspondence relationship for each Δt.

Also in the fourth embodiment, there is an advantage that an optimum extension element can be adopted according to the characteristics of the detection system. That is, the pulse extension can be optimized as a whole by using the extension elements 21 and 22 having different dispersion characteristics to obtain a desired dispersion. At this time, since the dichroic mirror 32 that divides the light according to the wavelength is used as the dividing element, each characteristic of the extending elements 21 and 22 can be further utilized. Then, as in the third embodiment, there is no light that is not used for the measurement, and the spectroscopic measurement device and the spectroscopic measurement method are highly efficient.

Next, a fifth embodiment will be described. FIG. 10 is a schematic view of the spectroscopic measuring device of the fifth embodiment.
In the fifth embodiment shown in FIG. 10, a WDM (wavelength division multiplexing) coupler 33 is used as the dividing element. Other configurations are the same as those of the third embodiment shown in FIG.
In this embodiment, the WDM coupler 33 is a fiber type, and a single-mode or multi-mode fiber fused and stretched is used. As shown in FIG. 10, one end on the incident side is terminated, and the light from the extending element 2 is incident from the other incident end 331. Light having a wavelength longer than the divided wavelength is emitted from one of the two branched emission ends 332, and a wavelength shorter than the divided wavelength is emitted from the other emission end 333.

In the fifth embodiment, since the fiber type WDM coupler 33 is used, when the fiber 20 is used as the extension element 2, it is suitable because it has a high affinity for each other. That is, since the fibers are connected to each other, they can be connected and transmitted with low loss by appropriately using a connector or the like, and a highly efficient spectroscopic measuring device can be obtained.
Similarly, when irradiating the object S, it is preferable to provide a beam expander 30, and the beam expander 30 is provided on the exit side of the WDM coupler 33 as a dividing element, as shown in FIG. Be done.

Further, the fiber type WDM coupler 33 can also be used as a dividing element in the fourth embodiment shown in FIG. In this case, the exit end of the fiber as the nonlinear element 12 is connected to the incident end 331 of the WDM coupler 33. Further, one of the branched exit ends 332 is connected to the first fiber 210, and the other 333 is connected to the second fiber 220. Here, too, since the fibers are connected to each other, low-loss connection and transmission can be achieved, and a highly efficient spectroscopic measurement device can be obtained.

FIG. 11 is a schematic view showing an example of another dividing element.
As shown in FIG. 11, as the dividing element, in addition to the above, a diffraction grating, an AWG (array waveguide grating), or the like can be used.
For example, as shown in FIG. 11 (1), the light from the stretching element 2 is wavelength-dispersed by the diffraction grating 35, condensed by the lens 363 according to the divided wavelength, and incident on the auxiliary fibers 361 and 362. The first auxiliary fiber 361 has an exit end arranged so as to irradiate an object S on the first receiving plate 61 with light, and the second auxiliary fiber 362 has an object on the second receiving plate 62. The exit end is arranged so as to irradiate S with light. At this time, each auxiliary fiber 361 and 362 can be used as a pulse extension fiber (first and second fibers 210 and 220).

Further, as shown in FIG. 11 (2), the AWG37 can be used as the dividing element. The AWG 37 is configured by forming each functional waveguide 372 to 377 on the substrate 371. Each functional waveguide includes a large number of array waveguides 372 having slightly different optical path lengths, slab waveguides 373 and 374 connected to both ends (incident side and emission side) of the array waveguide 372, and an incident side slab waveguide. There are an incident side waveguide 375 that causes light to enter the 373, and each emitting side waveguide 376 that extracts light of each wavelength from the emitting side slab waveguide 374.

The slab waveguides 373 and 374 are free spaces, and the light incident through the incident side waveguide 375 spreads in the incident side slab waveguide 373 and is incident on each array waveguide 372. Since each array waveguide 372 has a slightly different length, the light that reaches the end of each array waveguide 372 is out of phase (shifted) by this difference. Light is diffracted and emitted from each array waveguide 372, but the diffracted light passes through the exit-side slab waveguide 374 and reaches the incident end of the exit-side waveguide 376 while interfering with each other. At this time, due to the phase shift, the interference light has the highest intensity at the position corresponding to the wavelength. That is, light having different wavelengths is sequentially incident on each emission end waveguide 376, and the light is spatially dispersed. Strictly speaking, each exit side waveguide 376 is formed so that each incident end is located at such a spectroscopic position.

Two auxiliary fibers 377 and 378 are connected to the emission side waveguide 376 according to the division wavelength. That is, the first auxiliary fiber 377 is connected to the exit side waveguide 376 that emits a wavelength longer than the division wavelength, and the second auxiliary fiber 378 is connected to the exit side waveguide 376 that emits a wavelength shorter than the division wavelength. Is connected. A lens (not shown) is interposed or a fan-in-fan-out device is used to connect the auxiliary fibers 377 and 378. In this case as well, each of the auxiliary fibers 377 and 378 irradiates the object S on the receiving plates 61 and 62 with light, and can also be a fiber for pulse extension.
In addition, also in the example of FIGS. 11 (1) and 11 (2), since the affinity with the fiber is high, it can be easily connected to the fiber as the nonlinear element 12 with low loss, and a highly efficient spectroscopic measuring device. Can be.

Next, the sixth embodiment will be described. FIG. 12 is a schematic view of the spectroscopic measuring device of the sixth embodiment.
In the first embodiment described above, the transfer of the object S from the first receiving plate 61 to the second receiving plate 62 has been described with the image of being performed by the measurer, but the transfer mechanism of a robot or the like has been described. May be provided separately and automatically performed. The sixth embodiment is a modification of the third embodiment from this point of view.

In this embodiment, a moving mechanism 8 for moving the object S is provided in order to continuously perform the measurement in the first detection system and the measurement in the second detection system at high speed. More specifically, in this embodiment, a large number of receiving plates 63 are provided side by side in a horizontal direction. The moving mechanism 8 is a mechanism for linearly moving each receiving plate 63 in the direction in which the receiving plates 63 are arranged (hereinafter, moving direction). For example, assuming that the horizontal direction perpendicular to the moving direction is left and right, a configuration in which a linear guide is provided on one of the left and right sides and a linear drive source such as a linear motor is provided on the other side can be adopted. The receiving plates 63 are connected to each other and move linearly while being guided by a linear guide by a linear drive source.
In this embodiment, the receiving plate 63 is provided with a recess (not shown) so that the object S does not shift. Each object S is placed on each receiving plate 63 in a state of being dropped into the recess.

The moving mechanism 8 is provided with a control unit 81. The control unit 81 is configured to sequentially position each receiving plate 63 at an irradiation position set above the receivers 41 and 42. The control unit 81 controls each receiving plate 63 to move integrally with the linear drive source in a predetermined stroke. In the apparatus, a position where the light traveling through the first optical path P1 is irradiated (hereinafter, the first irradiation position) and a position where the light traveling through the second optical path P2 is irradiated (hereinafter, the second irradiation position). ) Is set, and the predetermined stroke is the distance between the first and second irradiation positions. The control unit 81 is configured to input a signal from the calculation means 5. The arithmetic means 5 is equipped with a sequence program 54 that operates each unit of the device including the control unit 81 in a predetermined sequence.

The spectroscopic measurement apparatus of the sixth embodiment is suitable for applications in which a large amount of objects S are sequentially spectroscopically measured at high speed. For example, spectroscopic measurements can be made during product inspection on the production line. The reference absorption spectrum in the case of a non-defective product has been investigated in advance, and the pass / fail of the product is determined by obtaining the absorption spectrum of each product by spectroscopic measurement and comparing it with the reference absorption spectrum. The device of the sixth embodiment is suitably used for such an application. In this application, as shown in FIG. 12, the pass / fail determination program 55 is mounted on the calculation means 5, and a file (not shown) in which the reference absorption spectrum is recorded is stored in the storage unit 52.

Specifically, each object S is dropped and held in a recess of each receiving plate 63. Then, the moving mechanism 8 sequentially moves the object S on each receiving plate 63 to the first irradiation position and the second irradiation position. Then, when it is located at the first irradiation position, the pulse light source 1 operates to irradiate the object S with light on the long wavelength side, and the transmitted light is received by the first receiver 41. Then, a data set (first data set) on the long wavelength side of the object S is temporarily recorded in a file.

The receiving plate 63 then moves to the second irradiation position, and in this state, the pulse light source 1 operates to irradiate the object S with light on the short wavelength side. Then, the data set on the short wavelength side (second data set) for the object S is temporarily recorded in the file.
After that, the measurement program 53 operates, and the absorption spectrum for the object S is calculated. Next, the pass / fail determination program 55 operates to perform pass / fail determination. That is, the calculated absorption spectrum is compared with the reference absorption spectrum, and it is determined whether or not the deviation is within a predetermined range. If it is within the specified range, it will be passed, and if it is outside the range, it will be rejected.

The moving mechanism 8 sequentially positions the object S on each receiving plate 63 at the first and second irradiation positions, and is irradiated with light at each position to acquire the first and second data sets. Then, the measurement program 53 sequentially calculates the absorption spectrum, and the pass / fail determination program determines the pass / fail. As a result of the pass / fail determination, the product is stored in the storage unit 52 as inspection information. It is more preferable that an exclusion mechanism is provided to exclude the rejected products from the production line and prevent them from being shipped.
Further, in the sixth embodiment, when the object S is placed at the second irradiation position and the measurement is performed, the next object S is placed at the first irradiation position and the measurement is performed at the same time. It is said. That is, the first data set and the second data set are acquired at the same time in one irradiation. In this case, the measurement program 53 in the calculation means 5 collectively calculates the entire absorption spectrum of the object S by combining the first data set in one irradiation and the second data set in the next irradiation. Programmed to result. For each data set, the absorption spectrum may be calculated by comparing with the reference absorption spectrum and then summarized, or each data set may be combined into the entire data set and then compared with the reference absorption spectrum to measure the absorption spectrum. The result may be good.

In the spectroscopic measurement device and the spectroscopic measurement method of the sixth embodiment, since each object S is moved by the moving mechanism 8 and sequentially located at the first and second irradiation positions, a large amount of objects S can be moved at high speed. It can be spectroscopically measured, and can be suitably used for applications with such a need.
In FIG. 12, the moving mechanism 8 is provided for the configuration of the third embodiment, but the moving mechanism 8 may be provided for the configuration of other embodiments such as the first embodiment. Of course it is good.

Next, the acquisition of the reference spectrum data will be supplementarily described.
As described above, reference spectrum data is acquired in advance when calculating the spectral characteristics of the object S. In this case, the acquisition of the reference spectrum data (measurement in a state where the object S is not arranged) is periodically performed as a calibration work in consideration of the temporal characteristic change of the pulse light source 1 and the receivers 41 and 42.

For more reliable spectroscopic measurements, it is preferable to acquire reference spectrum data frequently. As a method of doing this without reducing the efficiency of the measurement, it is preferable that when the data set is acquired by using one receiver, the reference data set is acquired by the other receiver. That is, in each of the first to fifth embodiments, when the object S is placed on the first receiving plate 61 and the first data set is acquired, the object S is placed on the second receiving plate 62. Since it is not mounted, the reference spectrum data for the second receiver 42 is acquired from the data output from the second receiver 42 at this time. Further, when the object S is placed on the second receiving plate 62 and the second data set is acquired by the output from the second receiver 42, the object S is placed on the first receiving plate 61. Since it is not installed, the reference data set for the second receiver 42 is acquired from the data output from the first receiver 41 at this time. In this way, the acquisition of each reference data set can be performed frequently in a state close in time to the actual measurement. Therefore, it becomes a more reliable spectroscopic measuring device and spectroscopic measuring method.

Next, the spectroscopic measuring device of the seventh embodiment will be described. FIG. 13 is a schematic view of the spectroscopic measuring device of the seventh embodiment.
In order to further improve the reliability of spectroscopic measurement, it is conceivable to acquire each data set and each reference data set at the same time (in real time). The seventh embodiment shown in FIG. 13 has this configuration.
The seventh embodiment shown in FIG. 13 is an embodiment in which real-time calibration is performed in the configuration of the third embodiment shown in FIG. Specifically, the first and second optical paths P1 and P2 extending from the dichroic mirror as the dividing element are provided with the first and second beam splitters 341 and 342, respectively.

The first beam splitter 33 further splits the first optical path P1 into two. Hereinafter, these two optical paths P11 and P12 will be referred to as a first measurement optical path and a first reference optical path. In the first measurement optical path P11, a first receiving plate 61 is arranged as in the first embodiment, and a first receiver 41 is arranged on the emitting side thereof. A first reference receiver 43 is arranged in the first reference optical path P12. A receiving plate is not arranged in the first reference optical path P12, and the light enters the first reference receiver 43 without passing through the object S.

The second beam splitter 34 also splits the second optical path P2 into two optical paths P21 and P22. Hereinafter, these two optical paths P21 and P22 will be referred to as a second measurement optical path and a second reference optical path. Similarly, a second receiving plate 62 is arranged in the second measurement optical path P21, and a second receiver 42 is arranged on the emitting side thereof. A second reference receiver 44 is arranged in the second reference optical path P22. A receiving plate is not arranged in the second reference optical path P22, and the light enters the second reference receiver 44 without passing through the object S.

The output from each of the receivers 41 to 44 is input to the calculation means 5 via the AD converter 7. The outputs from the receivers 41 to 44 are recorded in separate files as the first data set, the first reference data set, the second data set, and the second reference data set, and are recorded in the storage unit 52. It is temporarily memorized. Then, it is read by the measurement program 53 and the spectrum is acquired. Since the measurement program 53 itself is the same as described above, the description thereof will be omitted.
In the seventh embodiment, one light split by the beam splitters 33 and 34 is used for measurement and the other light is used for reference, and each reference data set is acquired in real time. Therefore, more reliable spectroscopic measurement can be performed.

Next, the eighth embodiment will be described. FIG. 14 is a schematic view of the spectroscopic measuring device of the eighth embodiment.
The spectroscopic measuring device of the eighth embodiment has a modified configuration of the third embodiment shown in FIG. Specifically, in this spectroscopic measurement device, a dividing element is arranged at a position where the light from the object S is divided, and the light from the object S is divided into two by the receivers 41 and 42. It is configured to receive light. In this embodiment, the dividing element is a dichroic mirror 32, but a beam splitter 31 may be used.

The light from the stretching element 2 is directly applied to the object S, and the light from the object S is divided by the dichroic mirror 32. Then, the divided long wavelength side light is received by the first receiver 41, and the short wavelength side light is received by the second receiver 42. The configuration of the calculation means for processing the output data from the receivers 41 and 42 to acquire the spectrum is the same as that of the third embodiment.

In the eighth embodiment, since the entire spectrum can be obtained by irradiating one object 2 with only one pulse, more accurate spectroscopic measurement can be performed in this respect. Reproducibility of wideband pulsed light when spectroscopic measurement is performed by irradiating different pulses for measurement of the first wavelength range and measurement of the second wavelength range for one object S as in each of the above embodiments. However, if it should decrease, the measurement accuracy will decrease. However, in the eighth embodiment, there is no such problem. Other embodiments other than the third embodiment can be modified in this way.

In FIG. 14, the object S is assumed to be in a liquid phase or a gas phase, and is placed in a transparent cell for measurement. Such a configuration may also be adopted in the first to seventh embodiments. Further, in the eighth embodiment, it is of course possible to adopt a configuration in which a receiving plate having a horizontal posture is provided and the light from the object on the receiving plate is divided. Since the light from the object S irradiated with the broadband pulsed light is divided by the dividing element, only one receiving plate is required. This makes it structurally simpler.

Next, another example of the extension element 2 will be described with reference to FIG. FIG. 15 is a schematic view showing another example of the extension element 2. As the extension element 2, in addition to single-mode fiber, single-mode multi-core fiber, single-mode bundle fiber, multi-mode fiber, and the like can be used. Further, the stretching element 2 can be configured by using a diffraction grating, a chirped fiber Bragg grating (CFBG), a prism or the like.
For example, as shown in FIG. 15 (1), wavelength dispersion is performed using two diffraction gratings 23. At this time, an optical path difference is formed according to the wavelength, and the pulse is extended in a state where the time wavelength uniqueness is achieved. In this example, the longer the wavelength of light, the shorter the optical path. As described above, since the diffraction grating can be used as the dividing element, a configuration in which both pulse extension and wavelength division are performed by the diffraction grating can be adopted.

Further, as shown in FIG. 15 (2), it is also possible to extend the pulse by using the CFBG24. The FBG is a fiber in which a part where the refractive index changes in the length direction of the core is periodically provided to form a diffraction grating. Of these, the CFBG is such that the function of the chirped mirror is realized by using the fiber. It can be said that the reflection position is set to be different depending on the wavelength. When used as the stretching element 2, in the CFBG24, for example, the light on the long wavelength side is reflected and returned on the front side in the traveling direction in the fiber, and is reflected and returned on the back side as it becomes the short wavelength side. It forms a refractive index changing layer in the core. This is the same configuration as a normal dispersion fiber. Since the shorter wavelength side returns later, the time wavelength uniqueness is similarly ensured.

Further, as shown in FIG. 15 (3), pulse extension can also be performed using the prism 25. In this example, the extension element 2 is configured by using four prisms 25 and arranging them so that the optical path becomes longer toward the shorter wavelength side. Also in this example, the shorter wavelength side is emitted later, so that the uniqueness of the time wavelength is ensured.
In the examples of FIGS. 15 (1) to 15 (3), an optical path difference is formed when the light is turned back. As a configuration for extracting light on the return path, a configuration in which a combination of a polarizing beam splitter and a 1/4 wave plate is arranged on an optical path in front of the extension element 2 can be adopted. On the outward path, the light travels in the order of the polarizing beam splitter and the 1/4 wave plate and enters the extension element 2, and on the return path, the light returned from the extension element 2 travels in the order of the 1/4 wave plate and the polarizing beam splitter. Constitute.

In each of the above embodiments, an InGaAs diode receiver is used in one detection system that detects light on the long wavelength side, and a Si diode receiver is used in the other detection system that detects light on the short wavelength side. , This is an example, and other types of receivers can be used. For example, a CdS receiver or the like can be used in the visible region, and a PbS receiver, an InSb receiver or the like can be used in the near infrared region.
The wavelength range of the spectroscopic measurement may also be a visible range or an infrared range longer than the near infrared.
In addition, although an example of an SC light source is taken as the pulse light source 1, other broadband pulse light sources such as an ASE (Amplified Spontaneous Emission) light source and an SLD (Superluminescent Diode) light source may be used. ..

In the present invention, it is not always essential to include a dividing element. When there is no dividing element, the first and second optical paths P1 and P2 are not divided, so that the first and second detection systems are formed by dividing them in time. That is, the first and second irradiation steps are performed on the object on the receiving plate. In each irradiation step, the receiving plate and the object hold the same position, but in the first irradiation step, the first receiver 41 is placed at the light receiving position and measurement is performed, and in the second irradiation step, the second The light receiver 42 is arranged at the light receiving position and measurement is performed. The measurement program 53 similarly calculates the spectrum based on the data sets from the receivers 41 and 42. A mechanism for replacing the receivers 41 and 42 (for example, a mechanism such as a revolver) may be provided.
Further, in each embodiment, the receiving plates 61 to 63 are in a horizontal posture, and the object S is irradiated with light from above. This is an example, and the object S is irradiated with light from the side. , Light may be emitted from an angle.

1 Pulse light source 11 Ultrashort pulse laser source 12 Non-linear element 2 Stretching element 21 Fiber 210 First fiber 220 Second fiber 3 Irradiation optical system 31 Beam splitter 32 Dichroic mirror 33 Wavelength split multiplex coupler 41-44 Receiver 5 Arithmetic means 51 Processor 52 Storage unit 53 Measurement program 61-63 Receiver plate 7 AD converter 8 Movement mechanism 81 Control unit

Claims (34)

A pulsed light source that emits wideband pulsed light,
An extension element that extends the pulse width of wideband pulsed light from a pulse light source so that the relationship between the elapsed time and wavelength in the pulse is 1: 1.
A dividing element that divides the wideband pulsed light whose pulse width is extended by the expanding element into two,
The first receiver that receives the light from the object irradiated with one of the light divided by the dividing element, and
A second receiver that receives light from the object irradiated with the other light divided by the dividing element, and
It is equipped with a calculation means for converting the temporal change of the output from the first receiver and the temporal change of the output from the second receiver into a spectrum.
The first and second receivers are spectroscopic measuring devices characterized in that their spectral sensitivity characteristics are different from each other. The first receiver is a receiver having a higher spectral sensitivity than the second receiver in the first wavelength range, and the second receiver is a second receiver different from the first wavelength range. A receiver having a higher spectral sensitivity than the first receiver in the wavelength range.
The calculation means converts the temporal change of the output from the first receiver into a spectrum for the first wavelength range, and temporally changes the output from the second receiver for the second wavelength range. The spectroscopic measuring apparatus according to claim 1, wherein the spectroscopic measuring apparatus is a means for converting a change into a spectrum. A pulsed light source that emits wideband pulsed light,
An extension element that extends the pulse width of wideband pulsed light from a pulse light source so that the relationship between the elapsed time and wavelength in the pulse is 1: 1.
A dividing element that divides wideband pulsed light whose pulse width is extended by the extending element into a long wavelength and a short wavelength with the dividing wavelength as a boundary.
The first receiver that receives the light from the object irradiated with the long wavelength light divided by the dividing element, and
A second receiver that receives light from an object irradiated with light of a shorter wavelength that is divided by a dividing element, and
A spectroscopic measuring apparatus including a calculation means for converting a temporal change of an output from a first receiver and a temporal change of an output from a second receiver into a spectrum. A pulsed light source that emits wideband pulsed light,
A dividing element that divides the wideband pulsed light emitted from the pulse light source into a long wavelength and a short wavelength with the dividing wavelength as a boundary.
A first extension element that extends the pulse width so that the relationship between the elapsed time in the pulse and the wavelength is 1: 1 for the light of the longer wavelength divided by the dividing element.
A second extending element that extends the pulse width so that the relationship between the elapsed time in the pulse and the wavelength is 1: 1 for the light of the shorter wavelength divided by the dividing element.
The first receiver that receives the light from the object irradiated with the light whose pulse width is extended by the first extension element, and
A second receiver that receives light from an object irradiated with light whose pulse width is extended by the second extension element, and
A spectroscopic measuring apparatus including a calculation means for converting a temporal change of an output from a first receiver and a temporal change of an output from a second receiver into a spectrum. A pulsed light source that emits wideband pulsed light,
An extension element that extends the pulse width of wideband pulsed light from a pulse light source so that the relationship between the elapsed time and wavelength in the pulse is 1: 1.
A dividing element that divides the light from an object irradiated with wideband pulsed light extended by the expanding element into two, and a dividing element.
The first receiver that receives one of the light divided by the dividing element, and
A second receiver that receives the other light divided by the dividing element, and
It is equipped with a calculation means for converting the temporal change of the output from the first receiver and the temporal change of the output from the second receiver into a spectrum.
The first and second receivers are spectroscopic measuring devices characterized in that their spectral sensitivity characteristics are different from each other. The first receiver is a receiver having a higher spectral sensitivity than the second receiver in the first wavelength range, and the second receiver is a second receiver different from the first wavelength range. A receiver having a higher spectral sensitivity than the first receiver in the wavelength range.
The calculation means converts the temporal change of the output from the first receiver into a spectrum for the first wavelength range, and temporally changes the output from the second receiver for the second wavelength range. The spectroscopic measuring apparatus according to claim 5, further comprising a means for converting a change into a spectrum. A pulsed light source that emits wideband pulsed light,
An extension element that extends the pulse width of wideband pulsed light from a pulse light source so that the relationship between the elapsed time and wavelength in the pulse is 1: 1.
A dividing element that divides the light from an object irradiated with wideband pulsed light extended by the stretching element into a long wavelength and a short wavelength with the dividing wavelength as a boundary.
The first receiver that receives the long wavelength light divided by the dividing element, and
A second receiver that receives light of the shorter wavelength divided by the dividing element, and
A spectroscopic measuring apparatus including a calculation means for converting a temporal change of an output from a first receiver and a temporal change of an output from a second receiver into a spectrum. The extension element is a single-mode fiber, a single-mode multi-core fiber, a bundle fiber of a single-mode fiber, a multi-mode fiber, a diffraction grating, a chirped fiber Bragg grating or a prism. 5, 6 or 7 of the spectroscopic measuring apparatus. The first extension element and the second extension element are single-mode fiber, single-mode multi-core fiber, single-mode fiber bundle fiber, multi-mode fiber, diffraction grating, chirp fiber Bragg grating or prism. The spectroscopic measuring apparatus according to claim 4. The spectroscopic measuring device according to claim 4 or 9, wherein the first stretching element and the second stretching element are elements having different stretching characteristics from each other. The spectroscopic measuring apparatus according to claim 3, 4 or 7, wherein the dividing element is any one of a dichroic mirror, a wavelength dividing multiplex coupler, a diffraction grating, and an array waveguide grating. The spectroscopic measuring apparatus according to claim 1 to 11, wherein the pulse light source is a supercontinuum light source. The spectroscopic measuring apparatus according to claim 12, wherein the pulse light source is a supercontinuum light source that outputs continuous light over a wavelength width of at least 10 nm in a wavelength region of 900 nm or more and 1300 nm or less. The spectroscopic measuring device according to any one of claims 1 to 13, wherein the first receiver is an InGaAs photodiode receiver. The spectroscopic measuring device according to any one of claims 1 to 14, wherein the second receiver is a Si photodiode receiver. A moving mechanism for moving the object between a position where one of the light divided by the dividing element is irradiated and a position where the other light is irradiated which is divided by the dividing element. The spectroscopic measuring device according to claim 1, 2, 5 or 6, wherein the spectroscopic measuring device is provided. Movement to move the object between the position where the long wavelength light is irradiated while being divided by the dividing element and the position where the short wavelength light is irradiated which is divided by the dividing element. The spectroscopic measuring apparatus according to claim 3 or 7, further comprising a mechanism. The object is moved between the position where the light whose pulse width is extended by the first stretching element is irradiated and the position where the light whose pulse width is extended by the second stretching element is irradiated. The spectroscopic measuring apparatus according to claim 4, further comprising a moving mechanism for causing the light to move. An emission process that emits wideband pulsed light from a pulsed light source,
A pulse extension step in which the pulse width of the wideband pulsed light emitted in the emission step is extended by an extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1.
In the pulse extension step, the wideband pulsed light whose pulse width is extended is divided into two by a dividing element, and the dividing step.
In the first light receiving step, in which the light from the object irradiated with one of the light divided in the dividing step is received by the first light receiver,
In the second light receiving step, in which the light from the object irradiated with the light of the other wavelength divided in the dividing step is received by the second light receiver,
Calculation of the temporal change of the output from the first receiver received in the first light receiving step and the temporal change of the output from the second receiver received in the second light receiving step into a spectrum by an arithmetic means. A spectroscopic measurement method comprising a process. The first receiver is a receiver having a higher spectral sensitivity than the second receiver in the first wavelength range, and the second receiver is a second receiver different from the first wavelength range. A receiver having a higher spectral sensitivity than the first receiver in the wavelength range.
In the calculation step, the temporal change of the output from the first receiver is converted into a spectrum for the first wavelength range, and the temporal change of the output from the second receiver for the second wavelength range. The spectroscopic measurement method according to claim 19, wherein the step is a step of converting a change into a spectrum. An emission process that emits wideband pulsed light from a pulsed light source,
A pulse extension step in which the pulse width of the wideband pulsed light emitted in the emission step is extended by an extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1.
In the pulse extension step, the wideband pulsed light whose pulse width is extended is divided into long wavelengths and short wavelengths with the division wavelength as a boundary by a dividing element.
In the first light receiving step, in which the light from the object irradiated with the long wavelength light divided in the dividing step is received by the first light receiver,
In the second light receiving step, in which the light from the object irradiated with the light of the shorter wavelength divided in the dividing step is received by the second light receiver,
Calculation of the temporal change of the output from the first receiver received in the first light receiving step and the temporal change of the output from the second receiver received in the second light receiving step into a spectrum by an arithmetic means. A spectroscopic measurement method comprising a process. An emission process that emits wideband pulsed light from a pulsed light source,
A dividing element that divides the wideband pulsed light emitted in the emission process into a long wavelength and a short wavelength with the dividing wavelength as a boundary.
The first pulse extension step in which the pulse is extended by the first extension element so that the relationship between the elapsed time in the pulse and the wavelength is 1: 1 for the light having a long wavelength among the broadband pulsed light divided in the division step. When,
A second pulse extension step in which the pulse is extended by the second extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1 for the light having the shorter wavelength divided in the division step.
In the first pulse extension step, the first light receiving step of receiving the light from the object irradiated with the pulse-stretched light by the first receiver, and
In the second pulse extension step, the second light receiving step of receiving the light from the object irradiated with the pulsed extended light by the second receiver, and
The calculation step of converting the temporal change of the output from the first receiver received in the first light receiving step and the temporal change of the output from the second receiver received in the second light receiving step into a spectrum. A spectroscopic measurement method characterized by being provided. An emission process that emits wideband pulsed light from a pulsed light source,
A pulse extension step in which the pulse width of the wideband pulsed light emitted in the emission step is extended by an extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1.
In the pulse extension step, the split step of splitting the light from the object irradiated with the broadband pulsed light whose pulse width is stretched into two by the split element,
In the first light receiving step, in which one of the light divided in the dividing step is received by the first light receiver,
In the second light receiving step, in which the other light divided in the dividing step is received by the second light receiver,
Calculation of the temporal change of the output from the first receiver received in the first light receiving step and the temporal change of the output from the second receiver received in the second light receiving step into a spectrum by an arithmetic means. A spectroscopic measurement method comprising a process. The first receiver is a receiver having a higher spectral sensitivity than the second receiver in the first wavelength range, and the second receiver is a second receiver different from the first wavelength range. A receiver having a higher spectral sensitivity than the first receiver in the wavelength range.
In the calculation step, the temporal change of the output from the first receiver is converted into a spectrum for the first wavelength range, and the temporal change of the output from the second receiver for the second wavelength range. The spectroscopic measurement method according to claim 23, wherein the step is a step of converting a change into a spectrum. An emission process that emits wideband pulsed light from a pulsed light source,
An extension step in which the pulse width of the wideband pulsed light emitted in the emission step is pulse-extended by an extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1.
In the stretching step, the splitting step of dividing the light from the object irradiated with the stretched broadband pulsed light into a long wavelength and a short wavelength with the splitting wavelength as a boundary by a splitting element,
In the first light receiving step, in which one of the light divided in the dividing step is received by the first light receiver,
In the second light receiving step, in which the other light divided in the dividing step is received by the second light receiver,
The calculation step of converting the temporal change of the output from the first receiver received in the first light receiving step and the temporal change of the output from the second receiver received in the second light receiving step into a spectrum. A spectroscopic measurement method characterized by being provided. Claims 19, 20, 21 wherein the extending element is a single-mode fiber, a single-mode multi-core fiber, a bundle fiber of a single-mode fiber, a multi-mode fiber, a diffraction grating, a chirp fiber bragg grating or a prism. 23, 24 or 25. The first extension element and the second extension element are single-mode fiber, single-mode multi-core fiber, single-mode fiber bundle fiber, multi-mode fiber, diffraction grating, chirp fiber Bragg grating or prism. 22. The spectroscopic measurement method according to claim 22. The spectroscopic measurement method according to claim 22 or 27, wherein the first stretching element and the second stretching element are elements having different stretching characteristics from each other. The spectroscopic measurement method according to claim 21, 22 or 25, wherein the dividing element is any one of a dichroic mirror, a wavelength dividing multiplex coupler, a diffraction grating, and an array waveguide grating. The spectroscopic measurement method according to any one of claims 19 to 29, wherein the broadband pulsed light is supercontinuum light. The spectroscopic measurement method according to claim 30, wherein the broadband pulsed light is supercontinuum light that is continuous over a wavelength width of at least 10 nm in a wavelength region of 900 nm or more and 1300 nm or less. The spectroscopic measurement method according to any one of claims 19 to 31, wherein the first receiver is an InGaAs photodiode receiver. The spectroscopic measurement method according to any one of claims 19 to 32, wherein the second receiver is a Si photodiode receiver. The first emission process for emitting broadband pulsed light from a pulse light source,
In the first pulse extension step, the pulse width of the broadband pulsed light emitted in the first emission step is extended by the extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1.
In the first pulse extension step, the first irradiation step of irradiating the object with the pulse-stretched broadband pulsed light, and
In the first light receiving step, in which the light from the object irradiated in the first irradiation step is received by the first light receiver,
A second emission step of emitting another broadband pulsed light from a pulsed light source,
A second pulse extension step in which the pulse width of the broadband pulsed light emitted in the second emission step is extended by an extension element so that the relationship between the elapsed time and the wavelength in the pulse is 1: 1.
In the second pulse extension step, the second irradiation step of irradiating the object with the pulse-extended broadband pulsed light, and
In the second light receiving step, the light from the object irradiated in the second irradiation step is received by the second light receiving device having different spectral sensitivity characteristics from the first light receiving device.
Calculation of the temporal change of the output from the first receiver received in the first light receiving step and the temporal change of the output from the second receiver received in the second light receiving step into a spectrum by an arithmetic means. A spectroscopic measurement method comprising a process.

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