JP2009097976A - Light measuring instrument and system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light measuring instrument and system that are small and portable, and can safely and easily perform measurement on various object materials at high resolution with laser-induced breakdown spectroscopy. <P>SOLUTION: The light measuring instrument 106 has: an optical device 114, which focuses light entered from either an object point 102 or an image point to the other point; a first optical fiber 112 and a laser source 120, which inject light of which energy density at an object point is higher than a breakdown threshold of the object material at the object point 102 and focus the light to the object point 102 through the optical device 114; and a spectrometer 118 and the second optical fiber 116, which spectrometrically measure the light focused by the optical device 114 on the object point side of the optical device 114 and output the result of a spectrometry as a signal. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical measurement apparatus and measurement system for performing spectral analysis, and more particularly, to an optical measurement apparatus and measurement system for performing spectral analysis by laser-induced breakdown spectroscopy (LIBS).

  Conventionally, as a technique for obtaining information on the composition of a substance, as described in Patent Document 1, laser-induced breakdown spectroscopy (hereinafter referred to as “LIBS”) is known. Yes. LIBS condenses and irradiates a measurement target material with laser light, causes a laser target breakdown to cause the measurement target material to become plasma, and detects and separates light generated from the generated plasma. Thus, various information about the measurement target substance is obtained.

  This technique has been mainly used for component analysis of solid surfaces. For example, it is used for component analysis on the surface of Mars, and for determining whether or not there is a violation of the surface paint of the bobsled edge at a bobsled competition.

JP 2004-226252 A

  By the way, in order to cause laser-induced breakdown in a measurement target substance, it is necessary to irradiate the measurement target substance with light having a high energy density equal to or higher than the breakdown threshold. Therefore, conventionally, a high-power gas laser has been used as a light source in the measurement by LIBS. Therefore, the measuring device for executing the measurement by LIBS is large-scale, and lacks portability.

  Moreover, in such a measuring device, since the output of the laser light source is too high, when combustible gas, liquid, plasma, living body and tissue thereof, protein derived from living body, sugar, nucleic acid, etc. are targeted, If the measurement target substance is changed, the desired measurement cannot be performed, and the measurement target substance may be damaged. In addition, since the output of the laser light source is too high, the wear of parts such as optical elements used in the measuring apparatus was severe.

  Furthermore, in such a measuring apparatus, since laser-induced breakdown is caused by a high energy laser beam, a situation in which a wide range of a measurement target substance is broken down over a long period of time occurs, which is extremely localized. It was difficult to measure in a wide measurement range. That is, in the conventional measuring apparatus, it is difficult to increase the resolution both spatially and temporally.

  In addition, this measuring apparatus includes two optical systems, an optical system for irradiating a measurement target substance with laser light and an optical system for condensing light generated from plasma. For this reason, in the conventional measuring apparatus, the relative positions of these two optical systems have to be adjusted with high accuracy, which is not convenient.

  Therefore, the present invention has been proposed in view of the above-described circumstances, and can perform measurement by LIBS with high resolution for various measurement target substances. Furthermore, the present invention is small, excellent in portability, and simple. It is another object of the present invention to provide an optical measurement device and a measurement system that can perform measurement safely.

  In order to solve the above-described problems and achieve the above object, a measuring apparatus according to the present invention has any one of the following configurations.

[Configuration 1]
An optical element for condensing the light on the other side when light from either the object point or the image point is incident, and an object point of the optical element by causing light to enter the optical element from the image point of the optical element A light emitting means for condensing light having an energy density equal to or greater than a breakdown threshold of the measurement target substance existing on the object point via the optical element, and spectroscopically measuring the light condensed on the image point of the optical element. And a spectroscopic measurement means for outputting a result of the spectroscopic measurement as a signal.

[Configuration 2]
In the optical measurement device having the configuration 1, the light emitting means condenses light having an energy density lower than the minimum ignition energy density of the measurement target substance existing at the object point of the optical element via the optical element. It is characterized by this.

[Configuration 3]
The optical measurement apparatus having the configuration 1 includes a control unit that controls the light emitted from the light emitting unit based on the result of the spectroscopic measurement from the spectroscopic measuring unit, and the light emitting unit is a measurement present at an object point of the optical element. Light having an energy density equal to or higher than the minimum ignition energy density of the target substance is condensed on the object point through the optical element.

[Configuration 4]
In the optical measurement device having any one of Configurations 1 to 3, the light emitting means is characterized in that light is incident along a predetermined optical axis passing through an image point of the optical element.

[Configuration 5]
In the optical measurement device having any one of Configurations 1 to 3, the light emitting means has a plurality of emission positions and condenses the emitted light at a plurality of object points of the optical element. is there.

[Configuration 6]
In the optical measurement device having the configuration 5, the spectroscopic measurement means performs spectroscopic measurement on each of the light at the plurality of condensing points selected from the plurality of image points corresponding to the plurality of object points, and the result of each spectroscopic measurement is obtained. It outputs as a signal.

[Configuration 7]
In the optical measurement device having any one of Configurations 1 to 6, the light emitting means is characterized in that light is incident on the optical element a predetermined number of times.

[Configuration 8]
In the optical measurement device having any one of Configurations 1 to 7, the spectroscopic measurement means sequentially performs spectroscopic measurement and outputs the result of each spectroscopic measurement as a time-series signal.

[Configuration 9]
In the optical measurement device having any one of Configurations 1 to 8, the optical element reflects the light incident from the object point and focuses it on the image point, and reflects the light incident from the image point to the object point. It is a reflective optical element for condensing light.

[Configuration 10]
In the optical measurement device having the configuration 9, the reflective optical element is formed integrally with the first surface and the second surface in order from the object point side, and the first surface and the second surface are the first region and the second surface, respectively. The first surface of the first surface is a concave transmission surface with respect to the object point side, the first region of the second surface is a concave reflection surface with respect to the object point side, and the second surface of the first surface The region is a reflecting surface, the second region of the second surface is a transmitting surface, and light incident from an object point is reflected by the first region of the second surface and the second region of the first surface to be collected at the image point. The light incident on the image point is reflected by the second region of the first surface and the first region of the second surface to be condensed on the object point.

[Configuration 11]
In the optical measurement device having any one of Configurations 1 to 10, the light that the light emitting unit enters the optical element is a laser beam.

[Configuration 12]
In the optical measurement device having the configuration 10, the light that is incident on the optical element by the light emitting means is a TEM ₀₁ ^* mode laser beam.

[Configuration 13]
In the optical measurement device having any one of Configurations 1 to 8, the optical element refracts the light incident from the object point and focuses the light on the image point, and refracts the light incident from the image point to the object point. It is a refracting optical element for condensing light.

[Configuration 14]
In the optical measurement device having the configuration 13, the light that the light emitting unit enters the optical element is light having a predetermined wavelength component.

  The measurement system according to the present invention has any one of the following configurations.

[Configuration 15]
An optical measurement device having any one of Configurations 1 to 14 and a signal processing unit that generates predetermined information on the measurement target substance based on a signal output from the optical measurement device of the optical measurement device. It is a feature.

[Configuration 16]
In the measurement system having the configuration 15, the signal processing unit performs peak detection in the result of the spectroscopic measurement by the spectroscopic measurement unit, and generates information on a predetermined feature of the measurement target substance based on the predetermined feature amount of the detected peak. It is characterized by doing.

[Configuration 17]
In the measurement system having the configuration 16, the information generation unit performs measurement based on at least one feature amount of the detected peak height, spectrum line width, line shape, and shift amount as the predetermined feature amount of the detected peak. Information on a predetermined characteristic of the target substance is generated.

[Configuration 18]
In the measurement system having the configuration 16, the information generation unit generates information on a predetermined feature of the measurement target substance based on a statistic regarding the predetermined feature of the detected peak as the predetermined feature amount of the detected peak. It is characterized by.

[Configuration 19]
In the measurement system having any one of Configurations 15 to 18, the information generation unit generates information on the amount of the measurement target substance as the predetermined information on the measurement target substance.

[Configuration 20]
In the measurement system having any one of Configurations 15 to 18, the information generation means generates information on the concentration of the measurement target substance as the predetermined information on the measurement target substance.

[Configuration 21]
In the measurement system having any one of Configurations 15 to 18, the information generation means generates information on the temperature of the measurement target substance as the predetermined information on the measurement target substance.

[Configuration 22]
In the measurement system having any one of Configurations 15 to 18, the information generation means generates information on the pressure of the measurement target substance as the predetermined information on the measurement target substance.

[Configuration 23]
In the measurement system having any one of Configurations 15 to 18, the information generation unit generates a plasma characteristic evaluation value of the measurement target substance as predetermined information regarding the measurement target substance.

[Configuration 24]
A position of the measurement target substance based on the result of the spectroscopic measurement of light at a plurality of condensing points output from the spectroscopic measurement means of the optical measurement apparatus, and predetermined characteristics of the measurement target substance; And a signal processing means for generating information relating to the relationship.

[Configuration 25]
An optical measurement device having configuration 8 and signal processing means for generating information relating to the relationship between the passage of time and a predetermined characteristic of the measurement target substance based on a time-series signal output from the optical measurement device, To do.

[Configuration 26]
An optical measurement device having configuration 14, and a signal for generating predetermined information related to the measurement target substance based on a signal output from the optical measurement device in the optical measurement device and a wavelength characteristic of light incident on the optical element by the light emitting means And a processing means.

  In the optical measurement device according to the present invention, the light that causes the breakdown of the measurement target substance to the measurement target substance and the light from the plasma generated by the breakdown are collected by one optical element. Done. Therefore, it is possible to reduce the size as compared with the conventional measuring apparatus provided with two optical systems, and it is not necessary to adjust the relative position of the two optical systems with high accuracy, and measurement is easy. Convenience has been improved.

  In the optical measurement device according to the present invention, it is possible to spectroscopically measure the light generated from the plasma at the time at which the breakdown occurs. Therefore, more accurate measurement is possible.

  In the optical measurement apparatus according to the present invention, light that is greater than or equal to the breakdown threshold of the measurement target substance and less than the minimum ignition energy density is condensed onto the measurement target substance by the optical element, so breakdown can be performed without igniting the measurement target substance. Can be generated. Therefore, it is possible to avoid the fact that the measurement target substance is ignited and the desired measurement purpose cannot be achieved, or the measurement target substance is damaged, and safe and accurate measurement is possible.

  Moreover, in the optical measuring device according to the present invention, it is possible to cause a chemical reaction to the measurement target substance, to cause a composition change, or to ignite by the optical measuring device. Furthermore, by controlling the emitted light based on the output signal of the spectroscopic measurement means, it is possible to efficiently cause a chemical reaction, composition change, or ignition in the measurement target substance.

  In the optical measurement device according to the present invention, breakdown can be caused at a plurality of positions of the measurement target substance. By collecting light generated by breakdown at a plurality of positions with an optical element and performing spectroscopic measurement with a spectroscopic measurement unit, it is possible to obtain more information regarding the measurement target substance.

  In the optical measurement device according to the present invention, it is possible to give energy to the measurement target substance in stages, or to cause breakdown multiple times in succession. In this way, it is possible to collect more information regarding the measurement target substance by condensing the light generated by the breakdown by the optical element and performing the spectroscopic measurement by the spectroscopic measurement means.

  In the optical measurement device according to the present invention, when the optical element is a reflective optical element, the optical element is configured to collect light by reflection, so that no specific aberration such as chromatic aberration occurs in the refractive optical system. The light emitted by the emitting means can be collected in a very narrow area, and breakdown can be caused only in that area. Therefore, it is possible to measure with high resolution both spatially and temporally. In addition, since breakdown can be caused by low-energy light, it is possible not only to reduce the size of the optical measurement device and improve portability, but also to improve safety during measurement. It becomes possible.

  In the optical measuring device according to the present invention, the laser beam is excellent in directivity and convergence, and the wavelength can be kept constant. Therefore, the laser beam is incident on the optical element and is passed through the optical element. By condensing the laser beam on the measurement target point, breakdown in the measurement target substance can be generated with high efficiency.

In the optical measurement device according to the present invention, when the optical element is a reflective optical element, the light beam can reach the object point due to the structure of the optical element by causing the TEM ₀₁ ^* mode laser beam to enter the optical element. The energy of the laser beam can be concentrated on the optical path. Therefore, it becomes possible to cause breakdown with high efficiency.

  In the optical measurement device according to the present invention, when the optical element is a refractive optical element, the optical element is configured to collect light by refraction, and therefore uses aberrations peculiar to the refractive optical system such as chromatic aberration. It is possible to induce breakdown or to perform spectroscopic measurement of light generated from plasma. In this case, it is preferable that the light incident on the optical element by the light emitting means is light having a predetermined wavelength component.

  In the optical measurement apparatus according to the present invention, breakdown can be caused at a predetermined position determined according to the wavelength of incident light by utilizing the aberration of the refractive optical element.

  In the optical measurement device according to the present invention, the light generated from the plasma can be spectroscopically measured at a plurality of positions conjugate to a plurality of points on the imaging plane by breakdown.

  In the optical measurement device according to the present invention, it is possible to obtain a measurement result at an optimal timing. In addition, it is possible to obtain information on the time change of the measurement target substance.

  In the measurement system according to the present invention, the measurement target substance and the light generated from the plasma are collected by one optical element, and the measurement target substance is based on the result of the spectroscopic measurement of the collected light. It is the structure which produces | generates the information regarding. Therefore, it is more portable than performing measurement using a conventional measuring device having two optical systems, and information on the predetermined characteristics of the measurement target substance can be obtained easily and safely with high spatial and temporal resolution. It is possible to obtain.

  In the measurement system according to the present invention, based on the predetermined feature value of the peak in the result of the spectroscopic measurement by the spectroscopic measurement means, the measurement object is easy and safe with high portability and high spatial and temporal resolution. It is possible to obtain information about certain characteristics of the substance.

  In the measurement system according to the present invention, based on at least one feature amount of peak height, spectral line width, line shape, and shift amount, it is excellent in portability and simple with a high spatial and temporal resolution. In addition, it is possible to safely obtain information on the predetermined characteristics of the measurement target substance.

  In the measurement system according to the present invention, information on the predetermined characteristics of the measurement target substance is easily and safely based on the statistics about the predetermined characteristics of the peak, with excellent portability and high spatial and temporal resolution. It is possible to obtain

  In the measurement system according to the present invention, it is excellent in portability, and it is possible to obtain information on the amount, concentration, temperature, or pressure of the measurement target substance simply and safely with high spatial and temporal resolution. is there.

  In the measurement system according to the present invention, it is possible to obtain a plasma characteristic evaluation value of a measurement target substance easily and safely with high resolution both spatially and temporally.

  In the measurement system according to the present invention, it is excellent in portability, and it is possible to obtain more information related to the measurement target substance simply and safely with high resolution both spatially and temporally.

  In the measurement system according to the present invention, it is determined according to the wavelength of the incident light by using the aberration of the refractive optical element, which is excellent in portability, simply and safely with high spatial and temporal resolution. It is possible to obtain information on a predetermined characteristic of the measurement target substance at a predetermined position.

  In the measurement system according to the present invention, information on the relationship between a plurality of positions and predetermined characteristics of a measurement target substance can be obtained easily and safely with high resolution both spatially and temporally. Is possible.

  In the measurement system according to the present invention, it is excellent in portability, and it is possible to easily and safely obtain information relating to the relationship between time and a predetermined characteristic of the measurement target substance with high spatial and temporal resolution. .

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  In the drawings used for the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description of the same parts will not be repeated.

[First Embodiment]
FIG. 1 shows a schematic configuration of a measurement system according to the first embodiment of the present invention. As shown in FIG. 1, the measurement system 100 is a device that performs spectroscopic measurement by LIBS on a solid, liquid, or gas (hereinafter referred to as “measurement target substance”) present at a predetermined measurement position 102. is there. That is, an optical measurement device 106 that outputs an electrical signal 104 corresponding to the intensity of light generated by the measurement target substance existing at the measurement position 102 being converted into plasma, and various signals for the electrical signal 104 output by the optical measurement device 106. A signal processing apparatus 110 that analyzes the physical and chemical state of plasma and the like and a substance to be measured (hereinafter referred to as “measurement target”) existing at the measurement position 102 by executing the process and outputs the analysis result 108; Have

  The optical measuring device 106 includes a laser light source 120 that generates a laser beam that causes breakdown in a measurement target substance existing at a measurement position 102, one end connected to the laser light source 120, and another laser beam incident from the one end. The first optical fiber 112 emitted from the end, the other end of the first optical fiber 112 and the measurement position 102 are arranged, and the laser emitted from the first optical fiber 112 is condensed at the measurement position 102. And an optical element 114 that condenses the light generated from the plasma emitted at the measurement position 102 at a predetermined position on the first optical fiber 112 side, and one end is disposed at the condensing position of the light generated from the plasma by the optical element 114 A second optical fiber 116 that emits light incident on the one end from the other end, and is connected to the other end of the second optical fiber 116 and is emitted from the other end. Spectrally the light, and a spectroscopic measurement unit 118 for outputting a signal corresponding to the intensity of each component is dispersed as an electrical signal 104. Specifically, the laser light source 120 is an Nd-YAG (Neodymium-Yttrium Aluminum Garnet) laser light source.

  FIG. 2 is a sectional view of the optical element 114 according to this embodiment. The optical element 114 is an integral optical element having a first surface 130 and a second surface 132, as shown in FIG. A space between the first surface 130 and the second surface 132 is a transparent medium. Specifically, the medium is so-called optical glass or synthetic quartz.

  The first surface 130 and the second surface 132 have first regions 130A and 132A on the outer peripheral side and second regions 130B and 132B at the center. The first region 130A of the first surface 130 is a spherical transmission surface having a predetermined point 102A as the center of curvature. A first reflective film 134 made of a reflective material (for example, aluminum) such as a metal material is deposited on the second region 130 </ b> B of the first surface 130. Therefore, the second region 130B of the first surface 130 is a reflection surface for incident light from the medium side. Further, a protective film 136 for protecting the reflective film 134 from the measurement target is formed on the measurement film 102 side of the reflective film 134. In the first region 132A of the second surface 132, a second reflective film 138 made of a reflective material similar to that of the first reflective film 134 is deposited. That is, the first region 132A of the second surface 132 is a concave reflection surface of light from the medium side. The second region 132B of the second surface 132 is a spherical transmission surface having a predetermined point 140 as the center of curvature. Hereinafter, the point 102A is referred to as an “object point”, and the point 140 is referred to as an “image point”.

  The light from the image point 140 is incident on the second region 132B of the second surface 132 and passes through the second region 132B of the second surface 132. At this time, the light from the image point 140 goes straight without being refracted. The light transmitted through the second region 132B of the second surface 132 travels in the medium between the first surface 130 and the second surface 132 and is reflected by the second region 130B of the first surface 130. The light reflected by the second region 130B of the first surface 130 is reflected by the first region 132A of the second surface 132, is emitted through the first region 130A of the first surface 130, and is focused on the object point 102A. To do. At this time, the light traveling toward the object point 102A travels straight without being refracted when passing through the first region 130A of the first surface 130.

  Conversely, the light from the object point 102A enters the first region 130A of the first surface 130, travels in the medium between the first surface 130 and the second surface 132, and reaches the first surface 130A. Reflected in one region 132A. The light reflected by the first region 132A of the second surface 132 is reflected by the second region 130B of the first surface 130, is emitted through the second region 132B of the second surface 132, and is focused on the image point 140. Is done.

  Therefore, in this optical element 114, for both the light from the object point 102A and the light from the image point 140, the surface that contributes to the optical path is only the reflecting surface, so that no chromatic aberration occurs.

  The exit end face 112 </ b> A of the first optical fiber 112 is disposed in the vicinity of the image point 140 toward the second region 130 </ b> B of the first face 130. Therefore, the laser light beam emitted through the first optical fiber 112 is condensed at the point 102B by the optical element 114. In addition, the incident end face 116 </ b> A of the second optical fiber 116 is also disposed near the image point 140 toward the second region 130 </ b> B of the first face 130. Therefore, the light generated at the point 102 </ b> C is collected on the second optical fiber 116 by the optical element 114.

  Therefore, as shown in FIG. 1, when the laser light source 120 emits a laser beam, the measurement target substance at the point 102B is broken down to be turned into plasma. When the region where this reaction occurs (hereinafter, this region is referred to as “reaction zone”) reaches point 102C, light is generated from the plasma at point 102C. This light is collected at the incident end face 116 </ b> A of the second optical fiber 116 and is incident on the second optical fiber 116. This incident light enters the end face on the spectroscopic measurement unit 118 side via the second optical fiber 116.

  FIG. 3 shows the configuration of the spectroscopic measurement unit 118 (see FIG. 1). As shown in FIG. 3, the spectroscopic measurement unit 118 is disposed on the optical axis of the light emitted from the second optical fiber 116, and converts the light emitted from the second optical fiber 116 into parallel light. 150, the first mirror 152 disposed on the optical axis of the light converted into parallel light by the collimator 150, and the optical axis of the light reflected from the first mirror 152 of the light generated from the plasma A second mirror 154, and a spectroscopic element 156 that is arranged on the optical axis of the light reflected from the second mirror 154 of the light generated from the plasma and that splits and emits the light reflected by the second mirror 154; , A third mirror 158 arranged on the optical path of the spectral light split by the spectroscopic element 156, and an incident spectrum arranged on the optical path of the spectral light reflected by the third mirror 158 Light sequentially photoelectrically converted, and a light receiving element 160 outputs a time series electric signal obtained as a result as an electric signal 104 described above.

  Specifically, the spectroscopic element 156 is a diffraction grating, a prism, or the like. Specifically, the light receiving element 160 is a so-called CCD image sensor or the like in which a large number of charge-coupled devices (CCD) and the like are arranged in a matrix. The mirrors 152, 154, and 158 each have a predetermined angle with respect to the incident light so that the light is not converged in the process from when the light generated from the plasma is incident until it is split by the spectroscopic element 156 and received by the light receiving element 160. It is arranged to make.

  The light that reaches the spectroscopic element 156 is split into spectral light by the spectroscopic element 156 and reaches the light receiving element 160 via the mirror 158. Therefore, the light receiving position of each component of the spectral light on the light receiving element 160 differs depending on the wavelength. On the other hand, the light receiving element 160 sequentially converts light received at each light receiving position, and outputs an electric signal 104 including information indicating the light receiving position at that time and the intensity of light at the light receiving position. Therefore, the electric signal 104 output from the light receiving element 160 includes information indicating the intensity at each time of each wavelength component included in the light generated from the plasma.

[Realization and Operation of Signal Processing Device 110 by Computer]
The functions of the signal processing apparatus 110 of the present embodiment can be realized by computer hardware, a program executed by the computer hardware, and data stored in the computer hardware. FIG. 4 shows the configuration of a computer system 180 that implements the functions of the signal processing device 110.

  As shown in FIG. 4, the computer system 180 includes a computer 184 having an interface 182 that receives input of the electrical signal 104 and output of the analysis result 108, an input device 198 such as a keyboard connected to the computer 184, and a display device. Output device 200.

  In addition to the interface 182, the computer 184 includes a bus 186 connected to the interface 182 and a central processing unit (CPU) 188. The computer 184 further includes a read-only memory (ROM) 190 that stores a boot-up program and the like, a random access memory (RAM) 192 that stores program instructions, system programs, work data, and the like, a hard disk 194, and a removable media drive 196. And have. The CPU 188, ROM 190, RAM 192, hard disk 194 and removable media drive 196 are all connected to the bus 186. Although not shown here, the computer 184 may further include a network adapter board that provides a connection to a local area network (LAN).

  A program that causes the computer system 180 to operate as the signal processing device 110 is stored in a removable medium inserted into the removable media drive 196, and the stored content is transferred to the hard disk 194. The program may be transmitted to the computer 184 through a network (not shown) and stored in the hard disk 194. The program is loaded into the RAM 192 when executed. Note that the program may be loaded directly into the RAM 192 from the above-described removable medium or network without going through the hard disk 194.

  This program includes a plurality of instructions for causing the computer 184 to execute the operation as the signal processing device 110. Some of the basic functions required for execution instructions for these operations are provided by operating system (OS), third party programs, or modules of various toolkits that are installed on the computer 184 and run on the computer 184. Therefore, this program does not necessarily have all the functions necessary for realizing the operation of the signal processing device 110. If this program has only instructions that implement each function of the signal processing device 110 by calling appropriate functions, tools, etc., in a controlled manner so that a desired result is obtained. Good. Since the operation of the computer itself is well known, description thereof will not be repeated here.

[Functional Configuration of Signal Processing Device 110]
FIG. 5 shows a functional configuration of the signal processing apparatus 110 in a block diagram form. As shown in FIG. 5, the signal processing device 110 receives the electric signal 104 and converts it into time-series data (hereinafter referred to as “spectral data”) representing the intensity of each wavelength component of light generated from plasma at each time. And a spectral data storage unit 222 that holds the spectral data generated by the signal conversion unit 220.

  The signal processing device 110 further scans the spectral data held in the spectral data storage unit 222 in the wavelength direction and the time direction, and a portion where the intensity of light generated from the plasma rises sharply (hereinafter, “peak”). A peak detection unit 224 that detects the peak feature amount detected by the peak detection unit 224 based on the spectroscopic data, and a peak feature amount extraction unit 226 that extracts the peak feature amount. A peak feature amount analyzing unit 228 generates statistical information on each peak feature amount by performing statistical processing and generates information representing the feature of light generated from the plasma as an analysis result.

  Specifically, the peak feature amount includes the peak appearance time, wavelength, peak height, that is, the intensity of the wavelength component at the peak apex (hereinafter referred to as “peak intensity”), spectral line width, shift amount, and line shape. It is. The information representing the characteristics of the light generated from the plasma is specifically the peak feature value, the ratio of the peak feature values between the peaks, and their average, mean square, dispersion, and time variation characteristics. .

  The signal processing apparatus 110 further includes a calibration information storage unit 230 that holds calibration information representing the relationship between the characteristics of light generated from plasma and the characteristics of the measurement target, and an analysis result by the peak feature amount analysis unit 228 based on the calibration information. Is converted into information related to the characteristics of the measurement target (hereinafter referred to as “measurement target information”) and output, and the measurement target information that holds the measurement target information output by the analysis result conversion unit 232 And a storage unit 234. The characteristics of the measurement target include, for example, the mass, flow rate, concentration, pressure, temperature, plasma characteristic evaluation value, etc. of the measurement target, their time fluctuations, the reaction zone thickness, the reaction arrival speed, and the like. The calibration information is a function, a correlation curve, a correspondence table, or the like that represents the relationship between the aforementioned characteristics of light generated from plasma and the aforementioned characteristics of the measurement target.

  The signal processing device 110 further reads out and outputs the measurement target information stored in the measurement target information storage unit 234 based on the user interface 238 that receives an operation for commanding the output of the measurement target information from the user and the operation that the user interface 238 receives. Output unit 236.

[Operation]
Hereinafter, an operation example of the measurement system 100 according to the present embodiment will be described. As shown in FIG. 1, the laser light source 120 emits a laser beam. The output of the laser beam is adjusted in advance so that the energy density at the object point is equal to or higher than the breakdown threshold of the measurement target substance existing at the object point when it is collected by the optical element 114. This laser beam emitted from the laser light source 120 is emitted from the emission end face 112A shown in FIG. 2 toward the optical element 114 via the first optical fiber 112. As shown in FIG. 2, the laser light beam emitted from the emission end face 112A passes through the second region 132B of the second surface 132, the second region 130B of the first surface 130, and the first region 132A of the second surface 132. And passes through the first region 130A of the first surface 130 and is collected at the point 102B. When the energy density at the point 102B becomes equal to or higher than the breakdown threshold value of the measurement target substance due to the focused laser beam, the measurement target substance is broken down and turned into plasma. When the measurement target substance is a combustible substance or a living body, the output of the laser beam is adjusted so that the energy density of the laser beam at the point 102B is not less than the breakdown threshold of the measurement target substance and less than the minimum ignition energy. If this is the case, breakdown can be caused to the measurement target substance safely and accurately.

  When the breakdown reaction zone reaches point 102C, light caused by plasma is generated at point 102C. The light is collected on the incident end face 116 </ b> A of the second optical fiber 116 and enters the second optical fiber 116 while reversing the same path as the laser beam.

  The incident light is emitted from the end face of the second optical fiber 116 on the spectroscopic measurement unit 118 side via the second optical fiber 116 as shown in FIG. The light incident on the spectroscopic measurement unit 118 is converted into parallel light by the collimator 150, then reflected by the first mirror 152 and the second mirror 154, and reaches the spectroscopic element 156. The light that reaches the spectroscopic element 156 is split into spectral light by the spectroscopic element 156 and reaches the light receiving element 160 via the mirror 158. The light receiving element 160 sequentially converts light received at each light receiving position, and outputs an electric signal 104 corresponding to information indicating the light receiving position at that time and the intensity of light at the light receiving position. The electric signal 104 is given to the signal processing device 110 as shown in FIGS.

  When the signal processing unit 110 receives the electrical signal 104, the signal conversion unit 220 converts the light receiving position information in the electrical signal 104 into light wavelength information and the signal intensity into light intensity information, as shown in FIG. Each is sequentially converted to generate spectral data. The signal conversion unit 220 stores this spectral data in the spectral data storage unit 222. In response to the spectral data being stored in the spectral data storage unit 222, the peak detector 224 scans the spectral data in the wavelength direction and the time direction, and whether or not a peak exists at that time at each time. Determine. The peak detector 224 gives the result of this determination to the spectral data and outputs it. In LIBS, a number of peaks unrelated to the peak corresponding to the plasma characteristics to be measured appear immediately after the laser beam is emitted and breakdown occurs, and a certain time has elapsed from the time when the laser was emitted. After a lapse, a peak corresponding to a plasma characteristic or the like to be measured appears. For this reason, the peak detection unit 224 does not determine that a peak is present in a time zone in which the former peak appears when performing a scan. For example, prior to scanning, the intensity value may be initialized to 0 in the former time zone using a time-direction window function prepared in advance for the spectral data.

  The peak feature amount extraction unit 226 identifies the appearance time, wavelength, and peak intensity of each peak. The peak feature amount extraction unit 226 further scans data around the peak of each peak, and identifies the spectral line width, shift amount, and line shape of the peak for each peak. Then, the identified information is given to the peak feature amount analysis unit 228 as the feature amount of each peak. The peak feature amount analysis unit 228 calculates the ratio of each feature amount of the peak between the peaks from the feature amount of each peak. The peak feature amount analysis unit 228 further performs statistical processing on each feature amount and its ratio, and calculates an average, a mean square, a variance, and a time variation characteristic thereof. The peak feature amount analysis unit 228 gives the feature amount of each peak, the ratio of each feature amount, and the result of statistical processing thereof to the analysis result conversion unit 232 as information representing the feature of light generated from the plasma.

  In response to the information indicating the characteristics of the light generated from the plasma from the peak feature amount analysis unit 228, the analysis result conversion unit 232 converts this information into the calibration information held in the calibration information storage unit 230. Based on this, it is converted into measurement target information.

  For example, the peak wavelength is converted into information representing the plasma characteristic evaluation value. Further, for example, the peak intensity of a single peak is converted into information representing the quantity, such as the number, mass, and flow rate of plasma at the appearance time of the peak. The average peak intensity is converted into information representing the average number, average mass, average flow rate, and the like of plasma in the time zone in which the measurement was performed. The time variation characteristic of the peak intensity is converted into information representing the time variation characteristic of the plasma amount.

  Further, for example, the spectral line width of the peak is converted into information representing the pressure at the measurement position at the appearance time of the peak. The average of the spectral line width is converted into information representing the average pressure at the measurement position in the time zone when the measurement was performed. The time variation characteristic of the spectral line width is converted into information representing the time variation characteristic of the pressure at the measurement position.

  In addition, for example, if light generated from a certain plasma has a property including a plurality of wavelength components, the ratio of the peak intensities between the wavelengths or the average thereof is converted into information representing the temperature of the plasma. . The time variation characteristic of the ratio of the peak intensities is converted into information representing the time variation characteristic of the temperature.

  Further, for example, if the measurement target includes a plurality of components, the ratio of the peak intensities of the wavelengths corresponding to the respective components is converted into information representing the concentration of the measurement target at the peak appearance time. The average of the peak intensity ratios is converted into information representing the average concentration of the measurement target in the time zone when the measurement was performed. The time variation characteristic of the ratio of peak intensities is converted into information representing the time variation characteristic of the concentration to be measured.

  Various information obtained in this way is stored in the measurement target information storage unit 234 as measurement target information. When the user interface 238 receives an operation requesting output of desired measurement target information from the user, the user interface 238 gives a command corresponding to this operation to the output unit 236. The output unit 236 reads information corresponding to the user's request from the measurement target information storage unit 234 according to the given command, and outputs it as the analysis result 108.

  As described above, the measurement system 100 according to the present embodiment has a configuration in which the optical element 114 performs both the condensing of the laser beam onto the measurement target substance and the condensing of the light generated from the plasma. Therefore, measurement is easier than conventional apparatuses that require two optical systems, and convenience is improved.

  Further, the optical element 114 is configured to collect light by reflection, and does not generate aberrations specific to the refractive optical system such as chromatic aberration. For this reason, the laser beam can be condensed in a very narrow area, and breakdown can be caused only in that area. Therefore, it is possible to measure with high resolution both spatially and temporally. In addition, breakdown can be generated without using a high-power laser light source as in the conventional device, so that the system can be downsized and the portability is improved. By using an output laser light source, safety during measurement can be improved. In addition, the use of a low-power laser light source reduces the effects of changes in the molecular structure of proteins, sugars, nucleic acids, and other biological molecules with complex molecular structures that are vulnerable to heat. It becomes possible.

  Furthermore, since the measurement system 100 according to the present embodiment is configured to sequentially perform spectroscopic measurement and obtain the result as a time-series signal, it is possible to obtain information on the measurement target using the measurement result at the optimal timing. In addition to being able to do so, it is possible to obtain information on the time change of the measurement target.

[Second Embodiment]
In the first embodiment described above, the emission position of the laser beam to the optical element 114 is arranged side by side with the light collection position of the light generated from the plasma. However, the present invention is not limited to such an embodiment. In the second embodiment described below, the optical axis of the laser beam is made to coincide with the optical axis of the light generated from the plasma.

  FIG. 6 shows a schematic configuration of the measurement system according to the present embodiment. As shown in FIG. 6, the measurement system 300 according to the present embodiment is an apparatus that performs spectroscopic measurement by LIBS on a substance present at a measurement position 102, and corresponds to the emission intensity of the substance present at the measurement position 102. An optical measurement device 302 that outputs an electrical signal 104 and a signal processing device 110 that is connected to the optical measurement device 302 so as to receive the electrical signal and is similar to that of the measurement system 100 according to the first embodiment.

The optical measuring device 302 has the same laser light source 120 and optical element 114 as those of the first embodiment. The optical measuring device 302 further includes a third optical fiber 304 having one end connected to the laser light source 120, a spectroscopic measurement unit 306 connected to the other end of the third optical fiber 304 and the signal processing device 110, and spectroscopic measurement. One end of the section 306 is connected to the side opposite to the third optical fiber 304, and the other end is provided with a fourth optical fiber 308 disposed toward the optical element 114. That is, in the present embodiment, the laser light source 120, the spectroscopic measurement unit 306, and the optical element 114 are arranged in series via the third optical fiber 304 and the fourth optical fiber 308. In the present embodiment, the end surface of the fourth optical fiber 308 on the optical element 114 side is disposed, for example, at the position of the image point 140 shown in FIG. The optical element 114 does not allow the light emitted from the image point 140 to the center of the second region 130B of the first surface 130 to reach the object point, and reaches the image point 140 from the second region 132B of the second surface 132. It will be emitted. Therefore, if the laser light source 120 emits a TEM ₀₁ ^* mode laser beam, the energy of the laser beam is concentrated around the image point 140, so that breakdown can be caused with high efficiency.

  FIG. 7 shows the configuration of the spectroscopic measurement unit 306. As shown in FIG. 7, the spectroscopic measurement unit 306 includes the same collimator 150, the first mirror 152, the second mirror 154, the spectroscopic element 156, the first collimator 150 and the spectroscopic device 156 according to the first embodiment. 3 mirrors 158 and light receiving element 160. The spectroscopic measurement unit 306 is connected to the fourth optical fiber 308 at a position corresponding to the connection position of the first optical fiber 116 in the spectroscopic measurement unit 118 according to the first embodiment.

  The spectroscopic measurement unit 306 is further disposed between the collimator 150 and the first mirror 152 so as to form a predetermined angle with respect to the optical axis of the light generated from the plasma, and the light from the incident direction of the light generated from the plasma. A half mirror 320 having transmission characteristics. The spectroscopic measurement unit 306 and the third optical fiber 304 are directed toward the first mirror 152 via the collimator 150 and the optical axis of the reflected light of the laser beam emitted from the third optical fiber 304 by the half mirror 320. Are connected in such a manner that the optical axes of the emitted light coincide with each other.

  The optical measurement device 302 according to the present embodiment operates as follows. When the laser light source 120 emits a laser beam, the laser beam is emitted into the spectroscopic measurement unit 306 shown in FIG. 7 via the third optical fiber 304 as shown in FIG. The laser beam emitted from the third optical fiber 304 is reflected by the half mirror 320 and is incident on the fourth optical fiber 308 via the collimator 150 as shown in FIG. The incident laser beam is emitted toward the optical element 114 from the end face of the fourth optical fiber 308 on the optical element 114 side. The emitted laser beam is condensed at the measurement position 102 by the optical element 114. Thereby, the substance at the measurement position 102 is broken down and turned into plasma. When light is generated from the plasma at the measurement position 102, the light is collected on the end surface of the fourth optical fiber 308 on the optical element 114 side while reversing the same path as the laser beam, and the fourth optical fiber 308 is collected. Is incident on.

  The light incident on the fourth optical fiber 308 is emitted from the end surface of the fourth optical fiber 308 on the spectroscopic measurement unit 306 side. The light incident on the spectroscopic measurement unit 306 passes through the collimator 150 and the half mirror 320 and reaches the first mirror 152 as shown in FIG. The light that has reached the first mirror 152 follows the same path as that of the light in the spectroscopic measurement unit 118 according to the first embodiment, is split by the spectroscopic element 156, and is converted into the electric signal 104 by the light receiving element 160. Is output. The signal processing device 110 processes and analyzes the output signal 104 by the same operation as in the first embodiment, and outputs an analysis result 108.

  As described above, the optical measurement device 302 according to the present embodiment has a configuration in which the optical axis of the laser beam coincides with the optical axis of the light generated from the plasma. The light generated from the plasma at the time can be measured. Therefore, more accurate measurement is possible.

[Other variations, etc.]
The spectroscopic measurement unit 306 according to the second embodiment described above has a configuration in which the optical axis of the laser beam and the beam of light generated from the plasma are matched by the half mirror 320. However, the present invention is not limited to such an embodiment. For example, the optical axes can be matched as follows. That is, first, the third optical fiber 304 and the fourth optical fiber 308 are connected to the spectroscopic measurement unit so that the optical axes of the other outgoing lights coincide with each other. Then, a half mirror is arranged in place of the first mirror 152 at the position of the first mirror 152 on the optical axis. Further, the spectroscopic element 156 is arranged so as not to cross the optical axis, and the angles of the second mirror 154 and the third mirror 158 with respect to the optical path are selected. The angle with respect to the optical axis of the half mirror disposed in place of the first mirror 152 is such that the half mirror reflects light from the collimator 150 toward the second mirror 154 and transmits the laser beam as it is. The angle is such that it has characteristics. The spectroscopic measurement unit having such a configuration and arrangement has the same operation as the spectroscopic measurement unit 306 according to the second embodiment.

  In each of the above-described embodiments, the laser beam is emitted to the optical element 114 through the optical fiber. However, it may be emitted to the optical element 114 directly from the laser light source or via a prism or mirror.

  In each of the above-described embodiments, each of the spectroscopic measurement units 118 and 306 spectrally divides the light generated from the plasma, converts the resulting spectral light into an electrical signal by the light receiving element 160, and outputs it. However, the present invention is not limited to such an embodiment. If the types of substances and plasma that can exist at the measurement position 102 are known, or if it is a measurement target to obtain information only about the measurement object having a predetermined plasma characteristic, the spectroscopic measurement unit Only a specific wavelength component in the light generated from the plasma may be extracted and converted into an electrical signal.

  For example, the light receiving element 160 may be arranged at a position where only a specific wavelength component of the spectral light that has been split passes. If there are a plurality of desired wavelength components, a plurality of light receiving elements may be arranged at positions corresponding to the desired wavelength components, respectively.

Also, for example, only a specific wavelength component may be extracted by an optical element having selective transmission, reflection, or absorption characteristics with respect to the wavelength of light, or a combination of optical systems composed of these optical elements. Good. FIG. 8 shows an example of the spectroscopic measurement unit 400 having such a configuration, which is used in place of the spectroscopic measurement unit 306 according to the second embodiment. As shown in FIG. 8, the third optical fiber 304 and the fourth optical fiber 308 are connected to the spectroscopic measurement unit 400 so that the optical axes of the emitted light of the optical fibers coincide with each other. The spectroscopic measurement unit 400 has a plurality of spectroscopic measurement units 410A, 410B, 410C,... For measuring the intensity of light having a wavelength selected in advance according to the measurement target (hereinafter simply referred to as “selected wavelength”). 410N. For example, if the measurement target substance is a mixture of gasoline and air, the selected wavelengths include light generated from OH ^* , light generated from CH ^* , light generated from CN ^*, and light generated from C ₂ ^*, etc. Each is selected. When this spectroscopic measurement unit 400 is applied, a wavelength other than the selected wavelength is selected as the wavelength of the laser beam.

  The spectroscopic measurement unit 410A is arranged on the optical axis of the light emitted from the third optical fiber 304 and the fourth optical fiber 308 so as to form a predetermined angle with respect to the optical axis, and is selected by the spectroscopic measurement unit 410A. A dichroic mirror 412A having a reflection characteristic with respect to a light component in a predetermined band and having a transmission characteristic with respect to a light component in another wavelength band having a wavelength other than the wavelength of the laser beam and the spectroscopic measurement unit 410A; A filter 414A disposed on the optical axis of the light reflected by the dichroic mirror 412A and having transmission characteristics with respect to the light component of the selected wavelength of the spectroscopic measurement unit 410A, and a filter on the optical axis of the light reflected by the dichroic mirror 412A Light receiving element 41 arranged on the opposite side of dichroic mirror 412A across 414A And an A.

  The configurations of the spectroscopic measurement units 410B, 410C,..., 410N are the same as those of the spectroscopic measurement unit 410A. However, the wavelength characteristics of the dichroic mirror and filter are selected according to the selected wavelength.

  The spectroscopic measurement unit 400 operates as follows. That is, when the laser light beam is emitted from the third optical fiber 304 into the spectroscopic measurement unit 400, the laser light beam passes through the dichroic mirrors from the dichroic mirror 410N to the dichroic mirror 412A in this order and passes through the fourth light. The light enters the fiber 308. Conversely, when light enters from the fourth optical fiber 308, the light is split by the dichroic mirrors 412A, 412B, 412C,. Of the dispersed light components, the components in the wavelength band near the selected wavelength pass through the filters 414A, 414B, 414C,..., 414N and reach the light receiving elements 416A, 416B, 416C,. Each of the light receiving elements 416A, 416B, 416C,..., 416N sequentially converts the reached light component into an electric signal 104 and outputs the electric signal 104.

  When the signal processing device 110 executes signal processing for generating the measurement target information 108 based on the electrical signal 104 thus output, peak detection and other processing are performed for wavelength bands other than the vicinity of the selected wavelength. No need to run. Since the amount of information to be processed is reduced, signal processing becomes efficient and high-speed processing becomes possible.

  If the analysis result based on the spectral line width in the wavelength direction, the shift amount, and the line shape is not required as measurement target information, the output signals of the light receiving elements 416A, 416B, 416C,. It does not necessarily have to be included. In such a case, a photomultiplier tube or the like may be applied as the light receiving elements 416A, 416B, 416C,. Since the photomultiplier tube has higher time response than an image sensor such as a CCD, measurement with high time resolution becomes possible.

  Further, not limited to the above-described example, a spectroscope using an optical filter, a diffraction element such as a diffraction grating, an Eschel diffraction grating, a Roland circle, a refraction element such as a prism or a lens, or a multiple reflection element is used. Spectroscopic measurement may be performed using any type of spectrometer such as a dispersion spectrometer or a Fourier transform spectrometer using an optical interferometer. In the embodiments described above, the configuration in which single point measurement is performed by a set of one laser light source and one spectroscopic measurement unit has been exemplified. However, the emission position of the laser beam and the condensing position of the light generated from the plasma can be selected from arbitrary positions on the imaging surface of the optical element 114. In such a case, the condensing position of the laser beam or the position where the light is generated from the plasma is a position corresponding to the selected position of the focal plane of the optical element 114. Therefore, for example, a plurality of laser light sources 120, a third optical fiber 304, a spectroscopic measurement unit 306, and a fourth optical fiber 308 shown in FIG. 6 are prepared in advance, and optical elements of the plurality of fourth optical fibers 308 are prepared. If the end surface on the 114 side is arranged on the image plane, measurement by LIBS is possible at a plurality of positions on the focal plane of the optical element 114. Furthermore, by integrating the results of spectroscopic measurement at a plurality of positions, it is possible to grasp a planar distribution such as the mass, flow rate, concentration, temperature, pressure, and plasma characteristic of the measurement target.

  The optical element 114 is not limited to the shape shown in FIG. 2, and the optical element 114 may have a tapered diameter between the first surface 130 and the second surface 132. Further, a notch may be provided near the side surface of the medium between the first surface and the second surface, and unnecessary light may be blocked by this notch. Further, the protective film 136 may be made of the same material as the medium, and the protective film may be formed over the entire first surface 130 with a sufficient thickness. In this case, a medium serving as a protective film may be bonded to the first surface 130 by welding or the like.

  Moreover, you may comprise 1st area | region 132A of the 2nd surface 132 as a surface which consists of a concave surface divided | segmented into the part which has a mutually different curvature center or a focus. In this case, each portion of the first region 132A of the second surface 132 has a different focal point, so that a plurality of image points can be formed by one optical element.

  Further, instead of the optical element 114, a single-surface reflective optical element such as a parabolic mirror may be used.

  In the above-described embodiment, the optical element 114 is an optical system that collects light by reflection, but an optical system such as a convex lens may be used instead of the optical element 114. However, in this case, it is desirable to reduce the aberration caused by the wavelength of light by various methods.

  When a refractive optical system is used, the chromatic aberration of the refractive optical system may be used. For example, it is possible to adjust the distance between the refractive optical element and the condensing position of the laser beam by appropriately selecting the wavelength of the laser beam. Furthermore, if multiple laser beam emission positions or condensing positions for light generated from plasma are prepared as described above, the mass and flow rate of the measurement target can be obtained by integrating the results of the spectroscopic measurement at the multiple positions. It is possible to grasp the spatial distribution of concentration, temperature, pressure, plasma characteristics and the like. In the optical measurement device of each of the above-described embodiments, if the laser light source emits energy that is equal to or higher than the minimum ignition energy of the measurement target substance, the optical measurement apparatus causes a chemical reaction to the measurement target substance. It is also possible to cause a composition change. If the measurement target substance is a flammable substance, the phenomenon of ignition may occur after plasmatization. Furthermore, if the substance is analyzed by LIBS in advance and the output and emission timing of the laser light source are controlled based on the analysis result, the chemical reaction, composition change, or Ignition can occur.

  Further, the measurement target substance may be irradiated with the laser light beam a plurality of times. By doing in this way, energy can be given to a measurement object substance in steps, or breakdown can be continuously generated a plurality of times. Further, the output of the laser light source may be adjusted every time the laser beam is emitted.

  In each of the above-described embodiments, an Nd-YAG laser light source is used as a light source for causing breakdown in a measurement target substance. However, a gas laser may be used as the light source. Various light sources such as a solid-state laser light source, a laser diode (LD), or a high-intensity light emitting diode (LED) can be used instead of the laser light source. In particular, since the optical element 114 has excellent light collecting performance, it is possible to cause breakdown even with a light source with low emission intensity. In addition, a light source that generates light by discharge such as glow, corona, arc, and spark, a radiation light source, a flame, and the like can also be used as a light source for causing breakdown in a measurement target substance.

  The embodiment disclosed this time is merely an example, and the scope of the present invention is not limited to only the above-described embodiments. The scope of the present invention is indicated by each claim in the claims after considering the description of the specification and the drawings, and includes all modifications within the meaning and scope equivalent to the words described therein. It is a waste.

[Industrial applicability]
As described above, the present invention can be used for precise analysis of gas, liquid, plasma, or a mixture thereof in a narrow space such as a combustion chamber of an automobile engine or in a nuclear reactor. . Moreover, since it is small and excellent in portability and can be measured easily, it can be used for environmental analysis or poison gas detection outdoors. Furthermore, since measurement can be performed safely, it can be used in the medical field.

1 is a schematic configuration diagram of a measurement system according to a first embodiment of the present invention. It is sectional drawing which shows the structure of the optical element in the said measurement system. It is a side view which shows the structure of the spectroscopic measurement part in the said measurement system. It is a hardware block diagram of the computer system which operate | moves as a signal processing apparatus in the said measurement system. It is a block diagram which shows the functional structure of the signal processing apparatus in the said measurement system. It is a schematic block diagram of the measurement system which concerns on the 2nd Embodiment of this invention. It is a side view which shows the structure of the spectroscopic measurement part in the said measurement system. It is a side view which shows the structure of the spectroscopic measurement part which can be used instead of the spectroscopic measurement part in the said measurement system.

Explanation of symbols

100, 300 Measurement system 102, 302 Measurement position 106 Optical measurement device 110 Signal processing device 112, 116, 304, 308 Optical fiber 114 Optical element 118, 306, 400 Spectrometer 120 Laser light source 130 First surface 130A, 132A First Area 130B, 132B Second area 132 Second surface 134, 138 Reflective film 136 Protective film 150 Collimator 152, 154, 158 Mirror 156 Spectroscopic element 160, 416A, 416B, 416C,..., 416N Light receiving element 180 Computer system 220 Signal converter 222 Spectral data storage unit 224 Peak detection unit 226 Peak feature amount extraction unit 228 Peak feature amount analysis unit 230 Calibration information storage unit 232 Analysis result conversion unit 234 Measurement object information storage unit 236 Output unit 238 User interface Interface 320 a half mirror 410A, 410B, 410C, ..., 410N spectrometry units 412A, 412B, 412C, ..., 412N dichroic mirrors 414A, 414B, 414C, ..., 414N filter

Claims (26)

An optical element for condensing the light on the other side when light from either the object point or the image point is incident;
Light is incident on the optical element from the image point of the optical element, and light having an energy density equal to or higher than the breakdown threshold of the measurement target substance existing at the object point of the optical element is collected at the object point via the optical element. Light emitting means for emitting light;
Spectroscopic measurement means for spectroscopically measuring light condensed on an image point of the optical element and outputting the result of the spectroscopic measurement as a signal. The light emitting means collects light having an energy density lower than a minimum ignition energy density of a measurement target substance existing at an object point of the optical element via the optical element. The optical measuring device according to 1. Based on the result of the spectroscopic measurement from the spectroscopic measurement means, the control means for controlling the emitted light of the light emitting means,
The control means controls the light emitting means so as to condense light above the minimum ignition energy density of the measurement target substance existing at the object point of the optical element through the optical element. The optical measurement device according to claim 1. 4. The optical measurement device according to claim 1, wherein the light emitting unit makes the light incident along a predetermined optical axis passing through an image point of the optical element. 5. . The optical measurement according to any one of claims 1 to 3, wherein the light emitting means has a plurality of emission positions and condenses the emitted light at a plurality of object points of the optical element. apparatus. The spectroscopic measurement means performs spectroscopic measurement of light at a plurality of condensing points selected from a plurality of image points corresponding to the plurality of object points, and outputs a result of each spectroscopic measurement as a signal. The optical measurement device according to claim 5. The optical measurement apparatus according to claim 1, wherein the light emitting unit causes light to enter the optical element a predetermined number of times. The optical measurement apparatus according to claim 1, wherein the spectroscopic measurement unit sequentially performs spectroscopic measurement and outputs a result of each spectroscopic measurement as a time-series signal. The optical element is a reflective optical element that reflects light incident from an object point and focuses it on an image point, reflects light incident from the image point, and focuses it on the object point. The optical measurement device according to claim 1. The reflective optical element is formed integrally with a first surface and a second surface in order from the object point side, and the first surface and the second surface each have a first region and a second region. The first region of the first surface is a concave transmission surface with respect to the object point side, the first region of the second surface is a concave reflection surface with respect to the object point side, and the second region of the first surface is a reflection surface. The second region of the second surface is made a transmission surface, and light incident from an object point is reflected by the first region of the second surface and the second region of the first surface to be condensed at an image point. The optical measurement device according to claim 9, wherein the light incident from an image point is reflected by the second region of the first surface and the first region of the second surface to be collected at an object point. The light measuring apparatus according to any one of claims 1 to 10, wherein the light incident on the optical element by the light emitting means is a laser beam. The optical measurement apparatus according to claim 10, wherein the light incident on the optical element by the light emitting means is a TEM ₀₁ ^* mode laser beam. The optical element is a refracting optical element that refracts light incident from an object point and condenses it on an image point, and refracts light incident from the image point and condenses it on the object point. The optical measurement device according to claim 1. The optical measurement apparatus according to claim 13, wherein the light incident on the optical element by the light emitting means is light having a predetermined wavelength component. An optical measuring device according to any one of claims 1 to 14,
And a signal processing unit configured to generate predetermined information related to the measurement target substance based on a signal output from the optical measurement device of the optical measurement device. The signal processing means performs peak detection in a result of spectroscopic measurement by the spectroscopic measurement means, and generates information on a predetermined characteristic of the measurement target substance based on a predetermined characteristic amount of the detected peak. The measurement system according to claim 15. The information generation means, as the predetermined feature amount of the detected peak, based on at least one feature amount of the detected peak height, spectral line width, line shape, and shift amount, the predetermined feature of the measurement target substance The measurement system according to claim 16, wherein information related to the information is generated. The information generation unit generates information on a predetermined feature of the measurement target substance based on a statistic regarding the predetermined feature of the detected peak as the predetermined feature amount of the detected peak. 16. The measurement system according to 16. The measurement system according to any one of claims 15 to 18, wherein the information generation unit generates information on the amount of the measurement target substance as the predetermined information on the measurement target substance. The measurement system according to any one of claims 15 to 18, wherein the information generation unit generates information on the concentration of the measurement target substance as predetermined information on the measurement target substance. The measurement system according to any one of claims 15 to 18, wherein the information generation unit generates information on a temperature of the measurement target substance as predetermined information on the measurement target substance. The measurement system according to any one of claims 15 to 18, wherein the information generation unit generates information on the pressure of the measurement target substance as the predetermined information on the measurement target substance. The measurement system according to any one of claims 15 to 18, wherein the information generation unit generates a plasma characteristic evaluation value of the measurement target substance as predetermined information regarding the measurement target substance. An optical measuring device according to claim 6;
Generates information on the relationship between the position of the substance to be measured and a predetermined characteristic of the substance to be measured based on the result of the spectroscopic measurement of light at a plurality of condensing points output from the spectroscopic measuring means of the optical measuring device And a signal processing means. An optical measurement device according to claim 8;
A measurement system comprising: a signal processing unit configured to generate information relating to a relationship between a passage of time and a predetermined characteristic of the measurement target substance based on a time-series signal output from the optical measurement device. An optical measurement device according to claim 14,
A signal processing unit configured to generate predetermined information on the measurement target substance based on a signal output from the optical measurement device in the optical measurement device and a wavelength characteristic of light incident on the optical element by the light emitting unit. A measurement system characterized by this.

Images