JPH08110270A - Fluid-temperature measuring apparatus utilizing fluorescence - Google Patents

Abstract

PURPOSE: To make it possible to measure the temperature of fluid without contact by casting laser light on a measuring region, through which fluid to be measures flows, and a standard cell, whose amount of state is known, and obtaining the ratio of the induced amounts of flurescence. CONSTITUTION: The laser light of a laser device 11 is split 12. One laser light is cast on fluid to be measured flowing through a measuring region, and the other laser light is reflected 14 and cast on the fluid, whose pressure and temperature are known, in a standard cell 15. The fluorescence generated by the laser induction is converged 17, respectively. A chopper 18 selectively switches both flurescences alternately and sends the fluorescence to a beam splitter 19. The splitter 19 performs adjustment so that both fluorescence optical paths go through the common optical path. A sharp- cut filter 20 cuts the scattered laser light and passes only the fluorescence. The electric signal, which is obtained by photoelectric conversion 21, is inputted into a signal processor 22. The effect of the noises is eleminated based on the ratio of the florescence-amount voltage of the region 13 to the fluorescence-amount voltage of the cell 15, and the temperature of the fluid of the measuring region 13 is computed. Thus, the accurate temperature measurement can be performed without contact.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid temperature measuring device utilizing fluorescence capable of non-contact measurement of fluid temperature.

[0002]

A thermocouple is generally used as a means for measuring the temperature of a fluid. When the temperature of a fluid is measured using this thermocouple, the thermocouple is inserted into the fluid, but when the thermocouple is inserted into the fluid, the flow is disturbed and the temperature of the fluid cannot be accurately measured. .

To compensate for this problem, FIG.
CARS (Coherent Anti-Stokes Raman Spectos shown in
It is known to measure the temperature of the fluid in a non-contact manner using copy). In this measurement method, the laser light from the Nd: YAG laser 1 is put into the dye laser 2 and the seed material in the fluid is excited by the laser light (frequency ω 1) and the Stokes light of the seed material (scattering of a wavelength longer than the irradiation light is scattered. Light) and laser light (frequency ω 2) having the same wavelength. These laser lights are integrated by the dichroic filter 3 into spot-like laser lights having frequencies (frequency) ω1 and ω2, and projected onto the fluid in the measurement area A to be measured. As a result, anti-Stokes light (frequency ω3: scattered light having a shorter wavelength than the irradiation light) of the seed material is resonantly generated. It is known that the fluid temperature can be calculated by analyzing and processing the spectrum analysis of the light of the anti-Stokes light ω3 by the monochromator 4 and the signal processor 5.

[0004]

However, in the case of CARS, since the spot-like laser light is used and the scattering cross-section is small, the amount of scattered light is small, and the SN ratio is poor, which makes it difficult to handle. There is a problem that it is difficult to improve the temperature measurement accuracy.

The present invention has been made in consideration of the above-mentioned circumstances, and irradiates a fluid to be measured in a measurement region with laser light,
An object of the present invention is to provide a fluid temperature measuring device using fluorescence, which can accurately measure the temperature of a fluid to be measured in a non-contact manner by utilizing the fluorescence induced by laser light, has a good SN ratio, and is easy to handle. To do.

Another object of the present invention is to provide a fluorescent light which can obtain a large amount of scattered fluorescent light by using laser-induced fluorescent light having a large scattering cross section and which can measure the temperature of a fluid to be measured with a good SN ratio and with high accuracy. In order to provide a fluid temperature measuring device using the same.

Another object of the present invention is to provide a fluorescence-based fluid temperature measuring device capable of accurately measuring the temperature of a fluid to be measured with non-contact by utilizing laser-induced fluorescence.

[0008]

In order to solve the above-mentioned problems, a fluid temperature measuring device using fluorescence according to the present invention, as set forth in claim 1, is a laser device for outputting a laser beam, Beam splitting means for splitting a laser beam from this laser device into two laser beams, and a standard cell in which a measurement region in a fluid to be measured to which each of the split laser beams is irradiated and a state quantity containing a seed substance are known. An optical switching means for selectively and selectively passing the fluorescence generated in the measurement area and the standard cell, an optical path combining means for matching the optical paths of the two fluorescences, and a fluorescent light from the optical path combining means for receiving the fluorescence. A photoelectric conversion element for converting into an electric signal, and a signal processor for calculating the temperature of the fluid to be measured from the ratio of the fluorescence amount from the measurement region and the fluorescence amount from the standard cell are provided.

Further, in order to solve the above-mentioned problems, a fluid temperature measuring device using fluorescence according to the present invention, as described in claim 2, a laser device for outputting a laser beam, and the laser device. Beam splitting means for splitting the laser light, a lens optical system for expanding the split laser light to form a two-dimensional laser light, a two-dimensional measurement region in the fluid to be measured irradiated with the two-dimensional laser light, and A standard cell with a known state quantity containing a seed substance, an optical switching means for selectively switching two-dimensional fluorescence generated in the measurement region and the standard cell, and optical path synthesis for matching the optical paths of two fluorescences. Means, a two-dimensional photoelectric conversion element for receiving the fluorescence from the optical path synthesizing means and converting it into an electric signal, and a plane temperature component of the fluid to be measured from the ratio of the fluorescence amount from the measurement region and the fluorescence amount from the standard cell. Fluid temperature measuring apparatus using the fluorescence, characterized by comprising a signal processor for calculating a.

Further, in order to solve the above-mentioned problems, a fluid temperature measuring device using fluorescence according to the present invention, as described in claim 3, is a laser device for outputting a laser beam, and the laser device. A beam splitting means for splitting the laser light, a scanning optical system having an optical fiber for scanning the split laser light, and a laser beam scanned by the scanning optical system in the fluid to be measured. A standard cell with a known state quantity containing a measurement region and a seed substance, an optical switching means for selectively and selectively passing the fluorescence generated in the measurement region and the standard cell, and an optical path for matching the optical paths of the two fluorescences. The synthesizing means, the photoelectric conversion element for receiving the fluorescence from the optical path synthesizing means and converting it into an electric signal, and the flow to be measured based on the ratio of the fluorescence quantity from the measurement region and the fluorescence quantity from the standard cell And a signal processing unit for calculating the temperature of the beam. Further, as described in claim 4, the scanning optical system includes a focusing objective lens for focusing the laser light split by the beam splitting means. An optical fiber for guiding the laser light from the objective lens, and a lens assembly connected to the exit end of the optical fiber for collimating the laser light.

In order to solve the above-mentioned problems, a fluid temperature measuring device utilizing fluorescence according to the present invention is further provided.
As described in claim 5, a laser device that outputs laser light, a beam splitting unit that splits the laser light from the laser device, and the split laser light are guided and expanded to generate a two-dimensional laser light. The scanning optical system to be formed, the two-dimensional measurement region in the fluid to be measured irradiated with the two-dimensional laser light and the standard cell in which the state quantity containing the seed substance is known, and the two cells generated in the measurement region and the standard cell, respectively. A light switching means for selectively passing two-dimensional fluorescence, an optical path combining means for matching the optical paths of two fluorescences, and a two-dimensional photoelectric conversion element for receiving the fluorescence from the optical path combining means and converting it into an electric signal. , A signal processor for calculating a plane temperature distribution of the fluid to be measured from the ratio of the fluorescence amount from the measurement region and the fluorescence amount from the standard cell, and scanning as described in claim 6. The optical system is An objective lens for condensing the laser light split by the beam splitting means, an optical fiber for guiding the laser light from this objective lens, and an exit end of this optical fiber are connected to expand the laser light. And a lens optical system for forming a two-dimensional laser beam.

On the other hand, in order to solve the above-mentioned problems, a fluid temperature measuring device using fluorescence according to the present invention is, as described in claim 7, a laser beam between a light switching means and a photoelectric conversion element. And a sharp cut filter that passes only fluorescence is provided. Further, as described in claim 8, the fluorescence amount can be calculated from the measurement region in the fluid to be measured in the state where the standard cell does not flow. It is a substitute.

[0013]

In the fluid temperature measuring device using fluorescence according to claim 1, the spot-shaped laser light divided by the beam splitting means is divided into a measurement area through which the fluid to be measured flows and a standard cell whose state quantity is known. Irradiation, the temperature of the fluid to be measured was measured in a non-contact manner by taking the ratio of the amount of fluorescence generated by this laser induction, so without disturbing the fluid flow,
Accurate temperature measurement can be performed.

Further, by dividing the fluorescence amount of the fluid to be measured from the measurement region by the fluorescence amount of the standard cell whose state quantity is known,
It is possible to eliminate the influence of noise from detection means such as photoelectric conversion elements,
The temperature of the fluid to be measured can be calculated as a difference from the standard cell temperature. And laser-induced fluorescence (Laser-Indu
Since the scattering cross section by ced Fluorescence is about 1000 times that of CARS, the amount of scattered light is large, and the SN ratio is correspondingly improved, and handling is simple, and the temperature of the fluid to be measured can be accurately measured.

Further, since the temperature of the fluid to be measured is measured by measuring the fluorescence induced by the laser light, the temperature of the fluid to be measured can be accurately and instantaneously measured. .

In the fluid temperature measuring device using fluorescence according to a second aspect, the fluid to be measured flowing in the measurement region and the fluid in the standard cell are each irradiated with a two-dimensional laser beam, and a two-dimensional laser light having a spread ( Since the plane temperature distribution of the fluid to be measured can be calculated by the (surface) measurement, there is an advantage that the temperature measurement of the fluid to be measured can be measured more accurately and more accurately than that of the first aspect. .

In the fluid temperature measuring device using fluorescence according to the third or fourth aspect, since the scanning optical system having the optical fiber is used, the optical path of the laser beam can be freely set by this scanning optical system, and the optical path can be set. The degree of freedom in selection is improved, and the overall adjustment and assembly of the fluid temperature measuring device is facilitated.

In the fluid temperature measuring device using fluorescence according to claim 5 or 6, an optical fiber is provided in the scanning optical system to improve the degree of freedom in selecting the optical path of the laser light, and the fluid temperature measuring device is entirely adjusted. And easy to assemble,
Two-dimensional (plane) with a spread by irradiating the measured fluid in the measurement area or the fluid in the standard cell with two-dimensional (plane) laser light
Since the plane temperature distribution of the fluid to be measured can be measured by the measurement, the temperature of the fluid to be measured can be measured accurately and accurately.

In the fluid temperature measuring device using fluorescence according to the seventh aspect, a sharp cut filter is provided to cut scattered laser light other than fluorescence so that only the fluorescence is input to the photoelectric conversion element. The influence of disturbances other than fluorescence can be reliably excluded, and the amount of fluorescence can be measured accurately.

In the fluid temperature measuring device using fluorescence according to claim 8, the standard cell is not always used, and the standard is used for measuring the fluorescence amount from the measurement region in the fluid to be measured in the state of no flow. Since it can be used as an alternative to the cell, the standard cell can be omitted, which is economically advantageous.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a fluid temperature measuring device using fluorescence according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a block diagram showing a first embodiment of a fluid temperature measuring device 10 using fluorescence, which has a laser device 11 for outputting laser light (monochromatic light) of a specific wavelength as a light source. A laser beam output from the laser device 11 is split into two laser beams by a beam splitter 12 as a beam splitter. The beam splitter 12 is adjusted so that the light intensities of the split laser lights are equal to each other.

One of the laser beams divided by the beam splitter 12 is applied to the fluid to be measured to form a measurement region 13, and the other laser beam passes through a reflection mirror 14 and its state quantity such as pressure and temperature is known. Is irradiated to the standard cell 15 of
It is designed to obtain a reference fluorescence as a reference. The laser light applied to the measurement area 13 and the standard cell 15 is stopped by the beam stoppers 16 and 16.

A small amount of seed substance as a fluorescent substance for generating fluorescence is injected into the fluid to be measured flowing in the measurement region 13 or the fluid in the standard cell 15 at a concentration of PPM order. The seed material includes iodine (I), NO, O _{2 in} the air, etc. Each seed material is irradiated with laser light of a specific wavelength to be laser-induced, and fluorescence is generated in the surroundings. There is. For example, the seed substances iodine, NO, and oxygen (O ₂ ) are adapted to generate fluorescence upon receiving laser irradiation from an argon ion laser, an ultraviolet dye laser, and an argon fluorine laser.
Therefore, the seed material has a special relationship with the laser device 11, and the type and output wavelength of the laser device 11 are determined by selecting the seed material.

The measurement area 13 and the standard cell 15 are irradiated with spot-shaped laser light of a specific wavelength, and the fluorescence generated by laser induction is focused by a condenser lens 17 and selectively switched by a chopper 18 as a light switching means. After that, the beam is adjusted by a beam splitter 19 as an optical path synthesizing means so as to pass through a common optical path, is input to a photoelectric conversion element 21 as a light receiving means through a sharp cut filter 20, and is proportional to the fluorescence amount by the photoelectric conversion element 21. Is converted into an electric signal. This electric signal is input to the signal processor 22,
Signal processing is performed here, and the temperature of the fluid to be measured is calculated. The sharp cut filter 20 is a filter that sharply cuts a short wavelength of fluorescence or less that is a predetermined wavelength or a long wavelength of fluorescence or more.
At 0, the scattered laser light from the measurement area 13 and the standard cell 15 is cut, and it is guided so that only the fluorescence passes.

By the way, the fluorescence from the standard cell 15 has its optical path adjusted by the mirror optical system of the reflection mirrors 24, 24 so as to approach the fluorescence from the measurement region 13, and the condenser lens 16 is provided.
And is guided to the chopper 18 of the light switching means. The fluorescence passing through the chopper 18 is guided to the beam splitter 19, and the beam splitter 19 matches the fluorescence from the measurement region 13 with the optical path of the standard cell 15. .

The switching of the chopper 18 is controlled by a control signal from the signal processor 22, and the fluorescence from the standard cell 15 and the fluorescence from the measurement region 13 are selectively and alternately transmitted to the beam splitter 19. In the beam splitter 19, the optical paths of both fluorescences are adjusted so as to pass through a common optical path and are guided to the photoelectric conversion element 21. Therefore, the fluorescence is input to the common photoelectric conversion element 21, and the calibration of the input signal becomes unnecessary.

The electric signal from the photoelectric conversion element 21 is input to the signal processor 22, and the fluorescence amount voltage of the measurement region 13 is divided by the fluorescence amount voltage of the standard cell 15 to obtain the influence of noise of the photoelectric conversion element 21 or the like. Can be eliminated, and the temperature of the measurement region 13 in the fluid can be calculated. At that time, since the scattering cross section of the laser-induced fluorescence obtained by irradiating the measurement region 13 with the laser light is about 1000 times that of CARS, the scattered light amount of the fluorescence becomes large, and therefore the SN ratio is improved and the handling becomes easy. At the same time, the accuracy of temperature measurement of the fluid to be measured can be improved.

As the photoelectric conversion element 21, a photomultiplier tube is generally used, but a semiconductor avalanche diode can also be used.

FIG. 2 is a block diagram showing a second embodiment of a fluid temperature measuring device 10A using fluorescence according to the present invention.
This fluid temperature measuring device has a laser device 11 that outputs a laser beam that laser-induces a seed material as a light source,
A laser beam from this laser device 11 is split into two laser beams by a beam splitter 12 as a beam splitting means. The divided laser light is expanded into a sheet by a cylindrical lens 26 that constitutes the lens optical system 25,
It is adjusted by the condenser lens 27 into parallel two-dimensional (plane) laser light. The two-dimensional laser light is a parallel laser light whose cross section has a required area.

One of the two-dimensional laser beams irradiates the fluid to be measured to form a two-dimensional (planar) measurement area 28. The fluid to be measured in this two-dimensional measurement area 28 is irradiated with the two-dimensional laser light. By this, laser induction occurs and two-dimensional fluorescence is generated. The other laser light is applied to the standard cell 15 whose state quantity such as pressure and temperature is known to obtain standard two-dimensional fluorescence. The two-dimensional laser light irradiating the measurement area 28 and the standard cell 15 is stopped by the beam stoppers 16, 16.

Therefore, the two-dimensional fluorescence from the measurement region 28 in the fluid and the two-dimensional fluorescence from the standard cell 15 are collected by the condenser lens 17 and condensed on the two-dimensional photoelectric conversion element 29. Has become. Of these, the fluorescence from the standard cell 15 is subjected to optical path adjustment using the mirror optical system of the reflection mirrors 24, 24, and is brought close to the fluorescence from the measurement region 28 and guided to the condenser lens 17.

The laser light guided to the condenser lens 17 is
Further, the light passes through the chopper 18 as the light converting means and is guided from the reflection mirror 24 to the beam splitter 19 as the optical path combining means. The beam splitter 19 is adjusted so that the optical paths of the two-dimensional fluorescence from the measurement area 28 and the two-dimensional fluorescence from the standard cell 15 coincide with each other. The fluorescent light adjusted by the beam splitter 19 to have a common optical path is then guided to the sharp cut filter 20, where scattered laser light other than fluorescent light is cut.

Ambient light other than fluorescence is removed by the sharp cut filter 20, and only fluorescence is generated by the two-dimensional photoelectric conversion element 29.
And is converted into an electric signal corresponding to the fluorescence amount. The electric signal from the two-dimensional photoelectric conversion element 29 is input to the signal processor 22, and the two-dimensional fluorescence amount voltage of the measurement region 28 is divided by the two-dimensional fluorescence amount voltage of the standard cell 15 to obtain the two-dimensional photoelectric conversion element 29 or the like. The influence of noise can be eliminated, and the planar temperature distribution of the fluid to be measured guided in the two-dimensional measurement area can be measured in two dimensions (surface) without contact, and can be calculated accurately. .

In order to accurately calculate the surface temperature of the fluid to be measured by this temperature measuring device 10A without performing temperature calibration, the state quantity such as temperature and pressure is the same as that of the known standard cell 15. In advance in the flow of the fluid to be measured in the measurement region 28, the two-dimensional fluorescence of the fluid to be measured from the measurement region 28 in the initial state is taken into the signal processor 22, and the processing in the signal processor 22 in the initial state is performed. Result is standard cell 1
It is required to confirm that it is in the same state as 5.

The signal processor 22 controls the chopper 18 so that the two-dimensional fluorescence from the measurement area 28 and the two-dimensional fluorescence from the standard cell 15 enter the two-dimensional photoelectric conversion element 29 alternately. There is. As the two-dimensional photoelectric conversion element 29, a CCD camera with an image intensifier, a photodiode array, or the like is used.

FIG. 3 shows a third embodiment of the fluid temperature measuring apparatus using fluorescence according to the present invention.

The fluid temperature measuring device 10B is capable of measuring the temperature of a fluid to be measured such as gas or liquid in a non-contact manner, and has a laser device 11 for outputting a laser beam for laser-inducing a seed substance. . This laser device 1
The laser beam from 1 is split into two laser beams by a beam splitter 12 as a beam splitting means. Each split laser light has the same light intensity.

Each of the divided laser beams is scanned by the scanning optical system 33. The scanning optical system 33 is the beam splitter 1.
A condenser objective lens 34 for condensing the laser light split by 2, an optical fiber 35 as an optical transmission means for guiding the split laser light from the objective lens 34, and an outlet end of the optical fiber 35. Lens assembly 36
And the lens assembly 36 has an optical fiber 3
The laser light from 5 is collimated and adjusted to a spot-shaped laser light. This scanning optical system 33 includes an optical fiber 3
Since the optical fiber 35 is provided, not only the straight optical path but also the curved optical path can be arbitrarily formed by the optical fiber 35 as needed, and the degree of freedom of the optical path for guiding the split laser light can be increased.

The spot-shaped laser light from each scanning optical system 33 is guided and irradiated to the measurement area 13 of the fluid and the standard cell 15 whose temperature and pressure state quantities are known.
A small amount (PPM order) of a seed substance as a fluorescent substance is put in the fluid to be measured flowing in the measurement region 13 or the fluid in the standard cell 15. The laser light irradiating the measurement area 13 and the standard cell 15 is stopped by the beam stoppers 16, 16.

By irradiating the measurement region 13 or the standard cell 15 with spot-shaped laser light, the seed material of the fluid to be measured or the fluid in the standard cell 15 is laser-induced to generate fluorescence. Fluorescence from measurement area 13 generated and standard cell 1
Fluorescence from 5 is condensed by a condenser lens 17, and is condensed on a photoelectric conversion element 21 via a chopper 18 which is a light conversion means, a beam splitter 19 which is an optical path combining means, and a sharp cut filter 20 which cuts scattered laser light. To be done. The fluorescence from the standard cell 15 is adjusted in optical path by the mirror optical system of the reflection mirror 24 so as to approach the fluorescence from the measurement region 13,
The light is guided from the condenser lens 17 to the beam splitter 19 via the chopper 18. In the beam splitter 19,
The optical paths of the fluorescent light from the measurement region 13 and the fluorescent light from the standard cell 15 are made to coincide with each other and guided so as to have a common optical path.

The switching operation of the chopper 18, which is the light switching means, is controlled by the control signal from the signal processor 22, and the fluorescence from the measurement region 13 and the fluorescence from the standard cell 15 are selectively alternately switched to perform photoelectric conversion. It is designed to guide the element 21.

The scattered light of the laser collected together with the fluorescence by the condenser lens 17 is sharp cut filter 2.
0 is removed, and only the fluorescence is incident on the photoelectric conversion element 21. The photoelectric conversion element 21 converts the input fluorescence into an electric signal, and the electric signal converted by the photoelectric conversion element 21 is output to the signal processor 22. In the signal processor 22, the fluorescence amount voltage of the measurement region 13 is divided by the fluorescence amount voltage of the standard cell 15 to calculate the temperature of the measurement region 13 in the fluid in which the influence of noise such as the photoelectric conversion element 21 is removed.

FIG. 4 shows a fourth embodiment of a fluid temperature measuring apparatus using fluorescence according to the present invention.

Fluid temperature measuring device 1 shown in this embodiment
0C is the surface of the fluid to be measured in a non-contact state (two-dimensional)
It is an accurate measurement. This fluid temperature measuring device 1
It has a laser device 11 as a light source, which outputs a laser beam for laser-induced 0C seed material. The laser light from the laser device 11 is split into two by a beam splitter 12 as a beam splitting means, and is guided to each scanning optical system 38.

The scanning optical system 38 condenses the divided laser light from the beam splitter 12 into a condensing objective lens 34.
And a bendable optical fiber 35 for guiding the laser light from the objective lens 34, and a lens optical system 40 connected to the exit end of the optical fiber 35. The lens optical system 40 includes the optical fiber 35. The laser light from the laser is expanded to form parallel two-dimensional laser light. The lens optical system 40 includes a lens assembly 41 such as a cylindrical lens, and a condenser lens 42 that adjusts the laser light magnified by the lens assembly 41 into parallel two-dimensional laser light. A parallel two-dimensional laser beam is obtained.

The one-dimensional scanning optical system 38 scans and expands the two-dimensional laser light to irradiate the fluid to be measured containing the seed substance to form a two-dimensional (planar) measurement region 28. In addition, the standard cell 15 passes through the other scanning optical system 38.
The two-dimensional laser light applied to the laser light is used to induce the laser in the fluid in the standard cell 15 containing the seed substance, the state amount of temperature and pressure of which is known, to obtain standard two-dimensional fluorescence. These laser lights are stopped by the beam stoppers 16, 16.

The two-dimensional fluorescence from the measurement region 28 in the fluid and the two-dimensional fluorescence from the standard cell 15 are collected by the condenser lens 17.
And is collected by the two-dimensional photoelectric conversion element 29. Of these, the fluorescence from the standard cell 15 is adjusted in its optical path by using the mirror optical system of the reflection mirror 24, is brought close to the fluorescence from the measurement region 28, and is guided to the condenser lens 17. The fluorescence guided by the condenser lens 17 passes through a chopper 18 serving as light switching means, a reflection mirror 24, and is guided to a beam splitter 19 serving as light combining means. The beam splitter 19 is adjusted so that the optical paths of the two-dimensional fluorescence from the measurement region 28 and the two-dimensional fluorescence from the standard cell 15 coincide with each other.

The fluorescence adjusted by the beam splitter 19 so as to have a common optical path is then guided to the sharp cut filter 20, where scattered laser light other than fluorescence is cut and removed.

Scattered light other than fluorescence is cut by the sharp cut filter 20, and only fluorescence is generated by the two-dimensional photoelectric conversion element 2.
It is incident on 9 and is converted into an electric signal here. The electric signal from the two-dimensional photoelectric conversion element 29 is input to the signal processor 22, and the electric signal is arithmetically processed by the signal processor 22. In the signal processor 22, noise of the two-dimensional photoelectric conversion element 29 or the like is removed by dividing the two-dimensional fluorescence amount voltage of the measurement region 28 by the two-dimensional fluorescence amount voltage of the standard cell 15, and the two-dimensional fluorescence amount voltage of the two-dimensional measurement region 28 in the fluid is removed. The temperature is calculated by two-dimensional (area) measurement.

The signal processor 22 controls the chopper 18 so that the two-dimensional fluorescence from the measurement area 28 and the two-dimensional fluorescence from the standard cell 15 enter the two-dimensional photoelectric conversion element 29 alternately. There is. As the two-dimensional photoelectric conversion element 29, a CCD camera with an image intensifier,
Alternatively, a photodiode array or the like is used.

In the description of each embodiment of the present invention, an example in which a standard cell having a known state quantity and containing a seed substance is used is shown. However, this standard cell is omitted, and the standard cell is not flowed in the fluid. Alternatively, the fluorescence amount in the measurement area may be measured to replace the standard cell.

Further, the fluorescence from the measurement region and the fluorescence from the standard cell are detected by separate photoelectric conversion elements, and the electric signal from the photoelectric conversion elements is subjected to signal processing to measure the temperature of the fluid to be measured. Good. In this case, it is necessary to calibrate the temperature in order to absorb the error caused by the accuracy problem between the photoelectric conversion elements.

[0054]

In the fluid temperature measuring device using fluorescence according to the first aspect of the present invention, the laser divided by the beam dividing means into the standard cells of which the measuring region through which the fluid to be measured flows and the state quantity are known. Since the temperature of the fluid to be measured is measured in a non-contact manner by irradiating light and measuring the ratio of the amount of fluorescence generated by this laser induction, accurate temperature measurement can be performed without disturbing the flow of the fluid. .

Further, by dividing the fluorescence amount of the fluid to be measured from the measurement region by the fluorescence amount of the standard cell whose state quantity is known,
It is possible to eliminate the influence of noise from detection means such as photoelectric conversion elements,
The temperature of the fluid to be measured can be calculated as a difference from the standard cell temperature. And laser-induced fluorescence (Laser-Indu
Since the scattering cross section by ced Fluorescence is about 1000 times that of CARS, the amount of scattered light is large, and the SN ratio is correspondingly improved, and handling is simple, and the temperature of the fluid to be measured can be accurately measured.

Further, since the temperature of the fluid to be measured is measured by measuring the fluorescence induced by the laser light irradiation, the temperature of the fluid to be measured can be accurately measured.

In the fluid temperature measuring device using fluorescence according to a second aspect, the fluid to be measured flowing in the measurement region or the fluid in the standard cell is irradiated with a two-dimensional laser beam to form a two-dimensional (surface) having a spread. ) It is possible to measure and calculate the plane temperature distribution of the fluid to be measured.
There is a merit that more accurate and accurate measurement can be performed as compared with the case of the first aspect.

In the fluid temperature measuring apparatus using fluorescence according to the third or fourth aspect, since the scanning optical system provided with the optical fiber is used, the optical path of the laser beam can be freely set by this scanning optical system, and the optical path can be set. The degree of freedom in selection is improved, and the overall adjustment and assembly of the fluid temperature measuring device is facilitated.

In the fluid temperature measuring device using fluorescence according to the fifth or sixth aspect, the scanning optical system is provided with an optical fiber to improve the degree of freedom in selecting the optical path of the laser light, and the fluid temperature measuring device is entirely adjusted. And easy to assemble,
Two-dimensional (plane) with a spread by irradiating the measured fluid in the measurement area or the fluid in the standard cell with two-dimensional (plane) laser light
Since it is possible to measure and calculate the planar temperature distribution of the fluid to be measured, the temperature of the fluid to be measured can be accurately and accurately measured.

In the fluid temperature measuring device using fluorescence according to the seventh aspect, a sharp cut filter is provided to cut off scattered laser light other than fluorescence so that only fluorescence enters the photoelectric conversion element. The influence of disturbances other than fluorescence can be reliably excluded, and the amount of fluorescence can be measured accurately.

In the fluorescence-based fluid temperature measuring device according to the eighth aspect, the standard cell is not always used, and the standard is used for measuring the fluorescence amount from the measurement region in the fluid to be measured in the state of no flow. Since it can be used as an alternative to the cell, the standard cell can be omitted, which is economically advantageous.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a fluid temperature measuring device using fluorescence according to the present invention.

FIG. 2 is a configuration diagram showing a second embodiment of a fluid temperature measuring device using fluorescence according to the present invention.

FIG. 3 is a configuration diagram showing a third embodiment of a fluid temperature measuring apparatus using fluorescence according to the present invention.

FIG. 4 is a configuration diagram showing a fourth embodiment of a fluid temperature measuring device using fluorescence according to the present invention.

FIG. 5 is a schematic diagram showing a conventional fluid temperature measuring device using CARS.

[Explanation of symbols]

 10, 10A, 10B, 10C Fluid temperature measuring device 11 Laser device 12 Beam splitter (beam splitting means) 13, 28 Measurement area 15 Standard cell 18 Chopper (light switching means) 19 Beam splitter (optical path synthesizing means) 20 Sherb cut filter 21 , 29 Photoelectric conversion element 22 Signal processor 25, 40 Lens optical system 33, 38 Scanning optical system 34 Condensing objective lens 35 Optical fiber 36, 41 Lens assembly

Claims (8)

[Claims] 1. A laser device that outputs a laser beam, a beam splitting device that splits the laser beam from the laser device into two laser beams, and a measurement in a fluid to be measured to which each of the split laser beams is irradiated. A standard cell in which a state quantity containing a region and a seed substance is known, an optical switching means for selectively and selectively passing the fluorescence generated in the measurement region and the standard cell, and an optical path synthesis for matching the optical paths of two fluorescences Means, a photoelectric conversion element for receiving the fluorescence from the optical path synthesizing means and converting it into an electric signal, and a signal for calculating the temperature of the fluid to be measured from the ratio of the fluorescence amount from the measurement region and the fluorescence amount from the standard cell. A fluid temperature measuring device using fluorescence, comprising: a processor. 2. A laser device for outputting a laser beam, a beam splitting device for splitting the laser beam from the laser device, and a lens optical system for expanding the split laser beam to form a two-dimensional laser beam. Selectively switch between the two-dimensional measurement region in the fluid to be irradiated with the two-dimensional laser light and the standard cell with a known state quantity containing the seed substance and the two-dimensional fluorescence generated in the measurement region and the standard cell. An optical switching means that allows light to pass through, an optical path combining means that matches the optical paths of two fluorescences, a two-dimensional photoelectric conversion element that receives the fluorescence from the optical path combining means and converts it into an electric signal, and the amount of fluorescence from the measurement region And a signal processor that calculates a planar temperature distribution of a fluid to be measured based on a ratio of the amount of fluorescence from the standard cell, and a fluid temperature measuring device using fluorescence. 3. A scanning optical system comprising a laser device for outputting a laser beam, a beam splitting means for splitting the laser beam from the laser device, and an optical fiber for scanning the split laser beam; and the above scanning. Selectively switch between the measurement area in the fluid to be measured, which is irradiated with the laser beam scanned by the optical system, and the standard cell in which the state quantity is known, and the fluorescence generated in the measurement area and the standard cell. A light switching means that allows the light to pass through, an optical path combining means that matches the optical paths of two fluorescences, a photoelectric conversion element that receives the fluorescence from the optical path combining means and converts it into an electric signal, and the amount of fluorescence from the measurement region. And a signal processor that calculates the temperature of the fluid to be measured from the ratio of the amount of fluorescence from the standard cell, and a fluid temperature measuring device using fluorescence. 4. The scanning optical system includes a focusing objective lens for focusing the laser light split by the beam splitting means, an optical fiber for guiding the laser light from the objective lens, and an exit end of the optical fiber. The fluid temperature measuring device using fluorescence according to claim 3, further comprising a lens assembly that is connected to the lens assembly and collimates the laser light. 5. A laser device for outputting a laser beam, a beam splitting device for splitting the laser beam from the laser device, and a scanning optics for guiding and expanding the split laser beam to form a two-dimensional laser beam. System, a standard cell with a known state quantity containing a two-dimensional measurement area and a seed substance in a fluid to be measured irradiated with a two-dimensional laser beam, and two-dimensional fluorescence generated in the measurement area and the standard cell, respectively From the measurement area, a light switching means that allows the light to be switched, a light path combining means that matches the light paths of the two fluorescences, a two-dimensional photoelectric conversion element that receives the fluorescence from the light path combining means and converts it into an electrical signal. And a signal processor for calculating a plane temperature distribution of a fluid to be measured from the ratio of the fluorescence amount from the standard cell to the fluorescence amount from the standard cell. 6. The scanning optical system includes a focusing objective lens for focusing the laser light split by the beam splitting means, an optical fiber for guiding the laser light from the objective lens, and an exit end of the optical fiber. 6. A fluid temperature measuring device utilizing fluorescence according to claim 5, further comprising: a lens optical system connected to the lens section and expanding a laser beam to form a two-dimensional laser beam. 7. A fluid temperature using fluorescence as claimed in claim 1, wherein a sharp cut filter for cutting laser light and passing only fluorescence is provided between the light switching means and the photoelectric conversion element. measuring device. 8. A fluid temperature measuring device utilizing fluorescence according to claim 1, 2, 3 or 5, wherein the standard cell is substituted for measurement of the amount of fluorescence from a measurement region in a fluid to be measured in the state of no flow. .