JP6792865B2 - Terahertz time domain spectrometer - Google Patents

Description

The present invention relates to a terahertz time-domain spectroscopic apparatus, in particular, the sample was placed in the path of the terahertz wave propagates, it is suitable for use in an apparatus for time domain measurement characteristics of the terahertz wave that has passed through the sample.

Surfactants (also called emulsifiers) have amphipathic molecules in which hydrophilic and hydrophobic groups are attached. In a surfactant mixed aqueous solution, amphipathic molecules spontaneously form various aggregates such as micelles and vesicles, which are spherical structures, depending on the mixing ratio and concentration. Since micelles and vesicles can wrap other molecules inside, they are expected to be applied not only to familiar applications such as soap, cosmetics, and food fields, but also to medical fields such as artificial blood and drug delivery. ..

Micelles and vesicles formed by multiple amphipathic molecules in a solution have a strong correlation with the intermolecular binding state, and a direct observation method is desired in order to accurately grasp the mixed state of the solution. It was. Conventionally, especially in a liquid chromatograph device frequently used for analysis of a liquid sample, it is possible to analyze a component molecule by isolating the molecule in the solution in the mixed state, but a plurality of molecules in the mixed state are analyzed. It was not possible to capture the unique state created by the mixture of molecules. It is difficult to obtain appropriate information for weak association of large molecules by infrared spectroscopy or NMR.

Micelle and vesicle are molecular aggregates formed only by intermolecular interactions such as hydrophobic interactions, electrostatic interactions, and hydrogen bonds, and their states are easily changed by disturbance factors. It is possible to take a small portion of the solution and capture its changed shape with a microscope, but it is difficult to observe more turbid concentrated solutions in real time. Therefore, since it is not possible to directly observe the state of micelles and vesicles, research and development and manufacturing have been carried out depending on indirect observation means and experience. As a result, the behavior of the transition between amphipathic molecules that do not have a spherical structure and micelles and between micelles and vesicles has not been fully understood at present.

In addition, an apparatus aimed at enabling measurement of spectral information with less noise has been proposed (see, for example, Patent Documents 1 and 2). In the apparatus described in Patent Documents 1 and 2, a nozzle for directly forming a thin film of a liquid sample is used, and the liquid sample is ejected from the nozzle by the pressure of a pump to generate a thin flat plate-shaped liquid film. Has been done.

Japanese Unexamined Patent Publication No. 2011-127950 Japanese Unexamined Patent Publication No. 2015-21908

The present invention has been made in view of the above-mentioned current situation, and the behavior of the transfer between the amphipathic molecule and the micelle, which does not have a spherical structure, and the micelle and the vesicle, and the components of the solution are used. The purpose is to enable measurement in a mixed state without isolation.

In order to solve the above-mentioned problems, in the present invention, the terahertz wave generated from the terahertz light source is detected via the sample liquid film, and the terahertz wave signal representing the waveform is analyzed. In the present invention, the analysis of the terahertz wave signal is performed as follows. That is, the transmittance with respect to frequency was expressed by Fourier transforming each of the plurality of terahertz wave signals obtained when a plurality of surfactant mixed aqueous solutions generated by changing the concentration of the surfactant were used as the sample liquid film. The frequency spectrum is acquired for each concentration of the surfactant, and the frequencies having a significant difference in transmittance among the plurality of frequency spectra are specified. Then, at the specified frequency, a correlation characteristic representing the transmittance with respect to the concentration of the surfactant is acquired.

According to the present invention constructed as described above, the component of the solution is isolated from the behavior of the transition between the micelle and the micelle in the state where the amphipathic molecule does not have a spherical structure, and between the micelle and the vesicle. It is possible to measure in a mixed state.

It is a figure which shows the structural example of the terahertz time domain spectroscope according to this embodiment. It is a figure which shows the structural example of the liquid circulation apparatus by this embodiment for forming a liquid film. It is a block diagram which shows the functional configuration example of the terahertz wave signal analysis apparatus by this embodiment. It is a figure for demonstrating the operation example of the frequency spectrum acquisition part and the frequency specifying part by this Embodiment. It is a figure which shows an example of the correlation characteristic acquired by the correlation characteristic acquisition part of this embodiment. It is a figure which shows the other structural example of the terahertz time domain spectroscope by this embodiment. It is a figure which shows the other structural example of the terahertz time domain spectroscope by this embodiment. It is a figure which shows the other structural example of the terahertz time domain spectroscope by this embodiment. It is a figure which shows the other structural example of the liquid circulation apparatus by this embodiment for forming a liquid film.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a configuration example of a terahertz time domain spectroscope according to the present embodiment. As shown in FIG. 1, the terahertz time region spectroscope of the present embodiment includes a femtosecond laser light source 10, a laser light spectroscopic unit 11, a terahertz wave generation semiconductor 12 (corresponding to a terahertz light source in the range of patent claims), and a terahertz wave. Terahertz wave focusing unit 14, terahertz wave focusing unit 14, terahertz wave detection semiconductor 15 (corresponding to the terahertz wave detection unit in the range of patent claims), variable optical delay unit 16 for time region spectroscopy, variable optical delay unit 17 for delay amount setting, and It is configured to include a terahertz wave signal analysis device 20 (corresponding to a terahertz wave signal analysis unit within the scope of the patent claim).

The laser light spectroscopic unit 11 uses the laser light (femtosecond laser pulse, which is excitation light) emitted from the femtosecond laser light source 10 as pump light for operating the terahertz wave generation semiconductor 12 which is a terahertz light source, and terahertz. It is divided into two types: sampled light for increasing the weak current generated by the terahertz wave incident on the terahertz wave detection semiconductor 15 which is a wave detection unit. Specifically, the laser light spectroscopic unit 11 is composed of a semi-transmissive mirror (half mirror).

The terahertz wave generation semiconductor 12 generates a terahertz wave in a predetermined frequency band by using the laser light output from the laser light spectroscopic unit 11. The terahertz wave spectroscopy unit 13 disperses the terahertz wave generated from the terahertz wave generation semiconductor 12 into two. Specifically, the terahertz wave spectroscope 13 is composed of a first parabolic mirror 13a, a first triangular prism 13b, and two first reflection mirrors 13c and 13d.

The terahertz wave generated from the terahertz wave generating semiconductor 12 is reflected by the first parabolic mirror 13a and output as a parallel ray bundle. The terahertz wave as a ray bundle is reflected by the two surfaces of the first triangular prism 13b and is dispersed in two directions. Then, the terahertz wave dispersed in one direction is reflected by the first reflection mirror 13c on one side and passes through the sample liquid film 101. The terahertz wave dispersed in the other direction is reflected by the other first reflection mirror 13d and passes through the reference liquid film 102. The details of the sample liquid film 101 and the reference liquid film 102 will be described later.

The terahertz wave focusing unit 14 focuses the terahertz wave that has passed through the sample liquid film 101 and the terahertz wave that has passed through the reference liquid film 102. Specifically, the terahertz wave focusing unit 14 is composed of a second parabolic mirror 14a, a second triangular prism 14b, and two second reflection mirrors 14c and 14d.

One terahertz wave that has passed through the sample liquid film 101 sequentially reflects the second reflection mirror 14c and the second triangular prism 14b, and is incident on the second parabolic mirror 14a. On the other hand, the other terahertz wave transmitted through the reference liquid film 102 sequentially reflects the other second reflecting mirror 14d and the second triangular prism 14b, and is incident on the second parabolic mirror 14a.

That is, the second triangular prism 14b reflects one terahertz wave that has passed through the sample liquid film 101 and the other terahertz wave that has passed through the reference liquid film 102 in one direction on each of the two surfaces, and the sample liquid. The terahertz wave transmitted through the film 101 and the terahertz wave transmitted through the reference liquid film 102 are emitted toward the second parabolic mirror 14a as a light bundle.

The second parabolic mirror 14a reflects a bundle of light rays (a bundle of terahertz waves transmitted through the sample liquid film 101 and a bundle of terahertz waves transmitted through the reference liquid film 102) incident in parallel from the second triangular prism 14b. , Focus on the terahertz wave detection semiconductor 15.

The terahertz wave detection semiconductor 15 detects the terahertz wave focused by the terahertz wave focusing unit 14, and outputs a terahertz wave signal representing the waveform. The terahertz wave signal analysis device 20 analyzes the terahertz wave signal output from the terahertz wave detection unit 15. This makes it possible to grasp the characteristics of the sample liquid film 101. The details of the analysis of the terahertz wave signal will be described later with reference to FIG.

The time domain variable optical delay unit 16 is provided in the path through which the sampled light, which is one of the laser lights dispersed by the laser light spectroscopic unit 11, propagates, and the delay amount of the sampled light is variably set. The time domain variable optical delay unit 16 has two reflection mirrors 16a and 16b, and the reflection mirrors 16a and 16b are configured to be physically translateable in the direction of arrow A. As a result, the delay time of the sampling light is made variable. The time domain variable optical delay unit 16 is used to measure the time change of the terahertz wave while shifting the timing at which the sampled light reaches the terahertz wave detection unit 15.

The variable optical delay unit 17 for setting the delay amount is provided on the path where the terahertz wave transmitted through the reference liquid film 102 propagates among the two terahertz waves dispersed by the terahertz wave spectroscopic unit 13, and the delay of the terahertz wave is provided. Variable amount setting. The variable optical delay unit 17 for setting the delay amount has the two reflection mirrors 13d and 14d described above, and the reflection mirrors 13d and 14d are configured to be physically parallel movable in the direction of the arrow B. .. The variable optical delay unit 17 for setting the delay amount has an optical path length of one path through which the terahertz wave passing through the sample liquid film 101 propagates and an optical path length of the path propagating by the other terahertz wave passing through the reference liquid film 102. It is used to make a predetermined difference between.

FIG. 2 is a diagram showing a configuration example of a liquid circulation device for producing the sample liquid film 101 and the reference liquid film 102. As shown in FIG. 2, the liquid circulation device of the present embodiment uses the tube pump 21, the sample liquid film generation unit 22S that generates the sample liquid film 101 using the liquid to be measured, and the reference liquid. It is configured to include a reference liquid film generation unit 22R that generates a reference liquid film 102. A syringe pump or other pump may be used instead of the tube pump 21.

The sample liquid film generation unit 22S includes a container 23S, an outward pipe 24S, a return pipe 25S, and a nozzle 26S. The container 23S is provided with a liquid tank 23Sa. Similarly, the reference liquid film generation unit 22R includes a container 23R, an outward pipe 24R, a return pipe 25R, and a nozzle 26R. The container 23R is provided with a liquid tank 23Ra. As described above, the sample liquid film generation unit 22S and the reference liquid film generation unit 22R have exactly the same configuration, and are structurally and mechanically the same.

The tube pump 21 sucks up the liquid to be measured from the liquid tank 23Sa of the sample liquid film generation unit 22S via the return pipe 25S, and guides the sucked liquid to the nozzle 26S via the outward pipe 24S. Then, the sample liquid film 101 is formed by ejecting the liquid from the nozzle 26S. The sample liquid film 101 becomes water droplets, accumulates in the liquid tank 23Sa, and is sucked up again by the tube pump 21.

Further, the tube pump 21 sucks up the reference liquid from the liquid tank 23Ra of the reference liquid film generation unit 22R via the return pipe 25R, and leads the sucked liquid to the nozzle 26R via the outward pipe 24R. Then, the reference liquid film 102 is formed by ejecting the liquid from the nozzle 26R. The reference liquid film 102 becomes water droplets, accumulates in the liquid tank 23Ra, and is sucked up again by the tube pump 21.

In this way, the liquid in the liquid tank 23Sa circulates in the sample liquid film generation unit 22S, and the sample liquid film 101 is formed by the nozzle 26S in the process of the circulation. Further, the liquid in the liquid tank 23Ra circulates in the sample liquid film generation unit 22R, and the reference liquid film 102 is formed by the nozzle 26R in the process of the circulation.

Here, two liquids having different properties are stored in the liquid tank 23Sa of the sample liquid film generation unit 22S and the liquid tank 23Ra of the reference liquid film generation unit 22R, and the two liquids are stored by one tube pump 21. The sample liquid film 101 and the reference liquid film 102 are formed by sucking up and circulating the sample liquid film 101. Then, the terahertz wave transmitted through the sample liquid film 101 and the reference liquid film 102 is detected by the terahertz wave detection semiconductor 15, and the terahertz wave signal output from the terahertz wave detection semiconductor 15 is detected by the terahertz wave signal analyzer 20. Analyze with.

At this time, the sample liquid is sampled by changing the delay amount of the terahertz wave on the reference liquid film 102 side by operating the variable optical delay unit 17 for setting the delay amount added to the optical path of the terahertz wave on the reference liquid film 102 side. Adjustment is made so that a predetermined optical path length difference occurs between the path through which the terahertz wave on the film 101 side propagates and the path through which the terahertz wave on the reference liquid film 102 side propagates.

According to the terahertz time region spectroscope of the present embodiment configured as described above, the terahertz wave detection semiconductor 15 is in a state where the terahertz wave transmitted through the sample liquid film 101 and the terahertz wave transmitted through the reference liquid film 102 interfere with each other. Will be detected at the same time. Therefore, if the sample liquid film 101 and the reference liquid film 102 are made of the same liquid, the spectral information of the sample liquid film 101 is offset by the spectral information of the reference liquid film 102. At this time, the environment at the time of measuring the terahertz wave, such as the terahertz wave generated by the semiconductor 12 for generating the terahertz wave, the temperature at the time of measurement, and the pulsation generated in the liquid film due to the operation of the tube pump 21, is the sample liquid film 101 and the reference liquid film. Since it is the same as 102, the offset effect can be enhanced.

On the other hand, if the sample liquid film 101 has different characteristics from the reference liquid film 102, the spectral information other than the different characteristics is canceled out, and the different characteristics, that is, the characteristic characteristics of the sample liquid film 101 are related. Only spectral information will be detected. In this way, the spectral information regarding the characteristics common to the sample liquid film 101 and the reference liquid film 102 is canceled out, so that the spectral information regarding the characteristic characteristics of the sample liquid film 101 can be sensitively detected. .. For example, the sample liquid film 101 is generated from a mixed aqueous solution of a surfactant in which a surfactant is mixed with pure water, while the reference liquid film 102 is generated from pure water, thereby being derived from the mixed surfactant. It is possible to detect spectral information on characteristic characteristics.

FIG. 3 is a block diagram showing a functional configuration example of the terahertz wave signal analysis device 20. As shown in FIG. 3, the terahertz wave signal analysis device 20 includes a frequency spectrum acquisition unit 20A, a frequency identification unit 20B, and a correlation characteristic acquisition unit 20C as its functional configuration. Each functional block 20A to 20C can be configured by any of hardware, DSP (Digital Signal Processor), and software. For example, when configured by software, each of the above functional blocks 20A to 20C is actually configured to include a computer CPU, RAM, ROM, etc., and is a program stored in a recording medium such as RAM, ROM, hard disk, or semiconductor memory. Is realized by the operation of.

The frequency spectrum acquisition unit 20A acquires a frequency spectrum representing the transmittance with respect to the frequency by Fourier transforming the terahertz wave signal detected by the terahertz wave detection semiconductor 15. In the present embodiment, in particular, the frequency spectrum acquisition unit 20A is detected by the terahertz wave detection semiconductor 15 when the sample liquid film 101 is generated from a plurality of surfactant mixed aqueous solutions generated by changing the concentration of the surfactant. By Fourier transforming each of a plurality of terahertz wave signals, a frequency spectrum representing the transmittance with respect to the frequency is acquired for each concentration of the surfactant.

The frequency specifying unit 20B identifies a frequency having a significant difference in transmittance among a plurality of frequency spectra acquired by the frequency spectrum acquisition unit 20A for each concentration of the surfactant.

FIG. 4 is a diagram for explaining an operation example of the frequency spectrum acquisition unit 20A and the frequency identification unit 20B. FIG. 4 is a diagram showing an example of a plurality of frequency spectra for each concentration acquired by the frequency spectrum acquisition unit 20A. Here, an example is shown in which six frequency spectra are obtained by using six kinds of fatty acid glycerin esters having different concentrations as surfactants and using a mixed aqueous solution of surfactants dissolved by ultrasonic stirring at 60 ° C. ing. The six concentrations are 0 g / L, 0.0125 g / L, 0.025 g / L, 0.05 g / L, 0.1 g / L, and 0.2 g / L.

The frequency specifying unit 20B identifies frequencies having a significant difference in transmittance among these six frequency spectra. In the example of FIG. 4, at a frequency of 0.4 THz, the difference in transmittance between the six frequency spectra is significantly large. Therefore, the frequency specifying unit 20B specifies the frequency of 0.4 THz.

The correlation characteristic acquisition unit 20C acquires the correlation characteristic representing the transmittance with respect to the concentration of the surfactant at the frequency specified by the frequency identification unit 20B. FIG. 5 is a diagram showing an example of the correlation characteristic acquired by the correlation characteristic acquisition unit 20C. The correlation characteristic of FIG. 5 shows the transmittance for 6 kinds of concentrations at 0.4 THz.

As shown in FIG. 5, the transmittance at a specific concentration appears as a deep dent. The concentration that appears as this deep dent is the critical micelle concentration that causes a transition between the amphipathic molecule that does not have a spherical structure and the micelle. In the example of FIG. 5, 0.05 [g / L] is shown as the micelle critical concentration of the fatty acid glycerin ester.

As described in detail above, according to the terahertz time region spectroscope of the present embodiment, the behavior of the transition between the amphipathic molecule and the micelle (particularly, the critical micelle concentration) is determined by the component of the aqueous surfactant mixed solution. It can be measured in a mixed state without isolation. By the same method, the behavior of the transition between micelles and vesicles (particularly, the critical vesicle concentration) can be measured in a mixed state without isolating the components of the surfactant mixed aqueous solution.

Further, according to the terahertz time region spectroscope of the present embodiment, it is possible to construct a production library of micelles and vesicles by performing measurement using various types of mixed aqueous solutions of surfactants.

FIG. 6 is a diagram showing another configuration example of the terahertz time domain spectroscope according to the present embodiment. Note that, in FIG. 6, those having the same reference numerals as those shown in FIG. 1 have the same functions, and therefore, duplicate description will be omitted here. The terahertz time region spectroscope shown in FIG. 6 differs from the configuration example of FIG. 1 in the configurations of the terahertz wave spectroscope and the terahertz wave focusing portion and the path through which the terahertz wave passes through the sample liquid film 101 and the reference liquid film 102. There is.

That is, the terahertz time region spectroscope shown in FIG. 6 includes a semitransmissive mirror (half mirror) 41 in place of the terahertz wave spectroscopic unit 13 and the terahertz wave focusing unit 14 shown in FIG. The half mirror 41 has both a terahertz wave spectroscopic unit and a terahertz wave focusing unit.

That is, the half mirror 41 as the terahertz wave spectroscopic unit disperses the terahertz wave generated from the terahertz wave generating semiconductor 12 in two directions. That is, the half mirror 41 is installed at an angle of 45 degrees with respect to the terahertz wave generating semiconductor 12, and has a part of the terahertz waves generated from the terahertz wave generating semiconductor 12 at an angle of 45 degrees. By reflecting a part of the sample liquid film 101 and transmitting a part of the material, the sample liquid film 101 and the reference liquid film 102 are separated.

The terahertz wave that has passed through the sample liquid film 101 is reflected by the reflection mirror 19 via the attenuation filter 18, and follows the original path toward the half mirror 41. Further, the terahertz wave transmitted through the reference liquid film 102 is reflected by the reflection mirrors 13d and 14d included in the variable optical delay unit 17 for setting the delay amount, and follows the original path toward the half mirror 41.

The half mirror 41 as a terahertz wave focusing unit transmits one terahertz wave that has passed through the sample liquid film 101 and reflects the other terahertz wave that has passed through the reference liquid film 102 at an angle of 45 degrees. , The two terahertz waves are focused in the direction of the terahertz wave detection semiconductor 15.

FIG. 7 is a diagram showing still another configuration example of the terahertz time domain spectroscope according to the present embodiment. Note that, in FIG. 7, those having the same reference numerals as those shown in FIG. 6 have the same functions, and therefore, duplicate description will be omitted here.

In the terahertz time domain spectroscope shown in FIG. 7, the function of the half mirror 41 shown in FIG. 6 is realized by two half mirrors 41'and 41 ". That is, the first half mirror 41'is a terahertz wave. The second half mirror 41 "corresponds to the spectroscopic portion, and corresponds to the terahertz wave focusing portion.

The first half mirror 41'spects the terahertz wave generated from the terahertz wave generating semiconductor 12 in two directions. That is, the first half mirror 41'is installed at an angle of 45 degrees with respect to the terahertz wave generating semiconductor 12, and a part of the terahertz wave generated from the terahertz wave generating semiconductor 12 is 45 degrees. By reflecting at an angle of 1 and transmitting a part of the sample liquid film 101, the sample liquid film 101 is separated into the path on which the sample liquid film 101 is installed and the path on which the reference liquid film 102 is installed.

The second half mirror 41 ”is installed at an angle of 45 degrees with respect to the terahertz wave detection semiconductor 15, and transmits one terahertz wave that has passed through the sample liquid film 101 and the reference liquid film 102. By reflecting the other terahertz wave transmitted through the above at an angle of 45 degrees, the two terahertz waves are focused in the direction of the terahertz wave detection semiconductor 15.

Further, in the terahertz time region spectroscope shown in FIG. 7, instead of the delay amount setting variable optical delay unit 17 and the reflection mirror 19 shown in FIG. 6, the delay amount setting variable optical delay unit 17'and the reflection mirror 19' It has. The variable optical delay unit 17'for setting the delay amount and the reflection mirror 19'have the same functions as the variable optical delay unit 17 for setting the delay amount and the reflection mirror 19 although the number of reflection mirrors used is different.

The terahertz wave that has passed through the first half mirror 41'is reflected by the reflection mirror 19', then passes through the sample liquid film 101 via the attenuation filter 18, and heads for the second half mirror 41'. The terahertz wave reflected by the first half mirror 41'at an angle of 45 degrees is reflected by the reflection mirror of the variable optical delay unit 17'for setting the delay amount, and then passes through the reference liquid film 102 to pass through the second half mirror. Head to Half Mirror 41 ".

As described above, the second half mirror 41 ”condenses one terahertz wave transmitted through the sample liquid film 101 and the other terahertz wave transmitted through the reference liquid film 102 in the direction of the terahertz wave detection semiconductor 15. To do.

By configuring the terahertz time domain spectroscope as shown in FIG. 6 or 7, there is an advantage that the configuration can be simplified as compared with FIG. In the present embodiment, FIGS. 1, 6 and 7 are shown as configuration examples of the terahertz time domain spectroscope, but these are only examples, and the present invention is not limited to these configurations. ..

In the above embodiment, an example in which the variable optical delay unit 17 for setting the delay amount is provided on the optical path on which the terahertz wave passes through the reference liquid film 102 has been described, but the delay amount is on the optical path on the sample liquid film 101 side. The variable optical delay unit 17 for setting may be provided. Alternatively, the variable optical delay unit 17 for setting the delay amount may be provided on both the optical path on the sample liquid film 101 side and the optical path on the reference liquid film 102 side.

Further, in the embodiment of FIG. 1, an example in which the delay amount of the terahertz wave is adjusted by the variable optical delay unit 17 for setting the delay amount has been described, but the reflection mirrors 13d and 14d included in the variable optical delay unit 17 for setting the delay amount. A liquid film moving portion that moves the arrangement position of the reference liquid film 102 may be further provided in accordance with the movement of the reference liquid film 102. For example, by configuring the nozzle 26R so that it can be physically translated in the direction of arrow B, it is possible to configure the liquid film moving portion. When the variable optical delay unit 17 for setting the delay amount is provided on the optical path on the sample liquid film 101 side, the nozzle 26S is configured to be physically movable in parallel.

Further, in the embodiment of FIG. 1, an example in which the sample liquid film 101 is arranged between the reflection mirrors 13c and 14c and the reference liquid film 102 is arranged between the reflection mirrors 13d and 14d has been described. Not limited to. For example, the sample liquid film 101 is arranged between the first triangular prism 13b and one of the first reflection mirrors 13c, and the reference liquid is placed between the first triangular prism 13b and the other first reflection mirror 13d. The film 102 may be arranged. In this case, the terahertz wave spectroscope is composed of a first parabolic mirror 13a and a first triangular prism 13b.

Further, in the above embodiment, the example in which the time domain variable optical delay unit 16 is arranged in the path through which the sampling light propagates has been described, but the time domain variable optical delay unit 16 is arranged in the path through which the pump light propagates. You may try to do it.

Further, in the above embodiment, the configuration in which the delay amount of the terahertz wave transmitted through the reference liquid film 102 is set to be variable by the variable optical delay unit 17 for setting the delay amount has been described, but the present invention is not limited to this. For example, the delay amount of the terahertz wave may be fixedly set to a predetermined value.

Further, in the above embodiment, an example of applying the terahertz time region spectroscope of the present invention to absorption spectroscopy has been described, but it can also be applied to reflection spectroscopy. FIG. 8 is a diagram showing a configuration example of a terahertz time domain spectroscope when applied to reflection spectroscopy. In addition, in FIG. 8, those having the same reference numerals as those shown in FIG. 6 have the same functions, and therefore, duplicate description will be omitted here.

In the configuration shown in FIG. 8, instead of the sample liquid film 101 and the reference liquid film 102, the sample 201 and the reference material 202 made of a material that does not transmit light or a material that scatters light are used. Further, instead of the variable optical delay unit 17 for setting the delay amount, the variable optical delay unit 17 ”for setting the optical delay amount by moving the arrangement position of the reference material 202 is provided. Note that the configuration of the terahertz time region spectroscope according to the reflection spectroscopy is not limited to this, as FIG. 8 shows only an example.

Further, in the above embodiment, in order to keep the temperature at which the mixing ratio of the surfactant is kept stable, a temperature control unit that gives thermal disturbance to the surfactant mixed aqueous solution in the liquid tank 23Sa is further provided. You may. As shown in FIG. 9, the temperature control unit includes, for example, a heating / cooling element 31S and a drive circuit 32 for driving the heating / cooling element 31S. The heating / cooling element 31S can be configured by, for example, a Peltier element.

Further, in the above embodiment, a flow velocity control unit for controlling the rate of deriving the surfactant mixed aqueous solution to the nozzle 26S may be further provided.
Further, in the above embodiment, a gas introduction mechanism for controlling the environmental atmosphere of the sample liquid film 101 and the reference liquid film 102 may be further provided.

Further, in the above embodiment, the terahertz wave detection semiconductor 15 sequentially detects the terahertz wave with a predetermined time resolution, and the terahertz wave signal analyzer 20 sequentially analyzes the sequentially detected terahertz wave signal to obtain the micelle. The state in which the mixed state of the vesicles changes from moment to moment may be measured with a predetermined time resolution.

Further, in the above embodiment, an example in which the terahertz wave is split into two and passed through the sample liquid film 101 and the reference liquid film 102, respectively, has been described, but the configuration of two splits is not essential. For example, first, the reference liquid film 102 generated with pure water having a reference air or a surfactant concentration of zero was measured via a terahertz wave, and then produced with a surfactant mixed aqueous solution having a non-zero concentration. The sample liquid film 101 may be measured via a terahertz wave.

Further, the detection may be performed by a fixed wavelength CW light source method. In addition, a device for changing the state in real time regarding the mixing of the liquid, a device for measuring the liquid film with terahertz, a device for using the sample in 1 way with a syringe pump to prevent foaming, and the like may be added.

In addition, the above embodiments are merely examples of embodiment of the present invention, and the technical scope of the present invention should not be construed in a limited manner. That is, the present invention can be implemented in various forms without departing from its gist or its main features.

11 Laser beam spectroscope 12 Terahertz wave generation semiconductor (terahertz wave light source)
13 Terahertz wave spectroscope 13a First parabolic mirror 13b First triangular prism 13c, 13d First reflection mirror 14 Terahertz wave focusing part 14a Second parabolic mirror 14b Second triangular prism 14c, 14d Reflection mirror of 2 15 Terahertz wave detection semiconductor (terahertz wave detection unit)
Variable optical delay unit for 16-hour region 17,17', 17 "Variable optical delay unit for setting delay amount (optical delay unit)
20 Terahertz wave signal analyzer (Terahertz wave signal analysis unit)
20A Frequency spectrum acquisition unit 20B Frequency identification unit 20C Correlation characteristic acquisition unit 41 Half mirror (Terahertz wave spectroscopy and terahertz wave focusing)
41'Half Mirror (Terahertz Wave Spectroscopy)
41 ”Half mirror (terahertz wave focusing part)
101 Sample liquid film 102 Reference liquid film 201 Sample 202 Reference material

Claims (6)

A terahertz wave spectroscope that splits terahertz waves generated from a terahertz light source into two,
In the path propagating the terahertz wave via the sample liquid film arranged in the path propagating by one terahertz wave split by the terahertz wave spectroscope and the other terahertz wave spectroscopic by the terahertz wave spectroscope. A terahertz wave focusing section that focuses the terahertz wave that has passed through the reference liquid film arranged in
A terahertz wave detection unit that detects a terahertz wave focused by the above terahertz wave focusing unit and outputs a terahertz wave signal representing the waveform, and a terahertz wave detection unit.
It is equipped with a terahertz wave signal analysis unit that analyzes the terahertz wave signal output from the terahertz wave detection unit.
The terahertz wave signal analysis unit
When the sample liquid film is generated from a plurality of surfactant mixed aqueous solutions generated by changing the concentration of the surfactant, the frequency is obtained by performing Fourier conversion on each of the plurality of terahertz wave signals detected by the terahertz wave detection unit. A frequency spectrum acquisition unit that acquires a frequency spectrum representing the transmittance for each concentration of the surfactant,
A frequency specifying unit that specifies a frequency having a significant difference in transmittance among a plurality of frequency spectra acquired for each concentration of the surfactant by the frequency spectrum acquisition unit, and a frequency specifying unit.
A terahertz time region spectroscope comprising a correlation characteristic acquisition unit that acquires a correlation characteristic representing a transmittance with respect to a concentration of the surfactant at a frequency specified by the frequency identification unit. Claim 1 is characterized in that the frequency specifying unit specifies a frequency at which the difference in transmittance is maximized among a plurality of frequency spectra acquired for each concentration of the surfactant by the frequency spectrum acquisition unit. The terahertz time region spectroscope according to. A sample liquid film generation unit that generates the above sample liquid film using the surfactant mixed aqueous solution to be measured,
A reference liquid film generator that generates the above reference liquid film using a reference liquid,
The terahertz time region spectroscope according to claim 1 or 2 , further comprising a temperature control unit that gives thermal disturbance to the surfactant mixed aqueous solution. The sample liquid film generation unit and the reference liquid film generation unit are respectively provided with a liquid tank, a pipe, and a nozzle, and a liquid is led out from the liquid tank to the nozzle via the pipe, and the liquid is led from the nozzle to the nozzle. Is configured to form the sample liquid film and the reference liquid film by ejecting.
The terahertz time region spectroscope according to any one of claims 1 to 3, further comprising a flow velocity control unit for controlling the rate of leading the liquid to the nozzle. The terahertz time region spectroscope according to any one of claims 1 to 4 , further comprising a gas introduction mechanism for controlling the environmental atmosphere of the sample liquid film and the reference liquid film. A femtosecond laser light source is used as the above terahertz light source.
The terahertz wave detection unit sequentially detects the terahertz wave with a predetermined time resolution, and the terahertz wave signal analysis unit sequentially analyzes the sequentially detected terahertz wave signal, according to claims 1 to 5 . The terahertz time region spectroscope according to any one item.