JP2018119894A - Laser spectroscopy inspection method and laser spectroscopy inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the repetition measurement accuracy by suppressing the reduction in analysis accuracy due to reflected light.SOLUTION: An inspection beam R1 radiated from a projection source 22A passes through outer walls Bwi and Bwo of a container B storing the gas to be analyzed, and is received by a detector 23A. The outer walls Bwi and Bwo of the container B through which the inspection beam R1 passes are disposed so as to form incident angles θ1 and θ2 with respect to the perpendicular line of an orthogonal plane of a beam axis Ro. The travel direction of the light that collides against the front surface and rear surface of the outer walls Bwi and Bwo and is reflected is deviated from the beam axis Ro, thereby eliminating or reducing the light reception of the reflected light by the detector 23A.SELECTED DRAWING: Figure 4

Description

  The present invention is a sealed container containing pharmaceuticals, beverages, foods, etc., optically transparent vials and food containers through which laser light is transmitted, or incubators, production equipment and combustion used for culture of bacteria and tissues A laser is emitted from the light source to the internal space of the container against a container such as a duct or tank that has an optically transparent portion through which exhaust gas (analyzed gas) flows or stays in the facility and through which the laser beam is transmitted. The present invention relates to a laser spectroscopic inspection method and a laser spectroscopic inspection device that measure the gas component amount, concentration, pressure, and the like of an analyte gas by irradiating light, allowing the analyte gas to pass through, and receiving the light by a detector.

  Utilizing frequency modulation (semiconductor laser) spectroscopy, the laser light is transmitted through the vial headspace, for example, and the oxygen concentration in the vial based on the change in the waveform of the frequency absorbed by the gas molecules in the headspace For example, Patent Literature 1 discloses a technique for analyzing the water concentration and the like.

  In Patent Document 1, reference vials and sample vials are held alternately on a transport conveyor, for example, and transported to an inspection area, and the pressure and concentration of the reference gas in the reference vial are set by a laser emission device and a laser detector, respectively. Analyzing and calibrating the detection value of the sample vial with the detection value of the reference vial.

Japanese Patent No. 4445971

  By the way, the laser light projected from the light projecting light source passes through the light projecting window of the light projecting light source, the front and rear surfaces of the outer wall on the incident side of the vial, the front and rear surfaces of the outer wall on the emission side, and the light receiving window of the detector. During transmission through these transmissive outer walls, part of the laser light is reflected and polarized, increasing the amount of polarization in the detector. In addition, the reflected reflected laser light waveforms overlap, causing the laser light to resonate or change in wavelength. In this way, the reflected light generated when the laser light is projected and projected by the light projecting light source and light receiving light source, the light receiving window and the outer wall of the vial bottle causes resonance and a change in wavelength, resulting in disturbances and reducing analysis accuracy. There was a problem.

  In Patent Document 1, the analysis accuracy is improved by calibrating the detection value of the sample vial with the detection value of the reference vial, but it is necessary to increase the detection frequency of the reference vial and the detection efficiency is poor. .

  The present invention provides a laser spectroscopic inspection method and a laser spectroscopic inspection device capable of suppressing a decrease in analysis accuracy due to a reflected beam generated when laser light passes through the outer wall of a container, and performing stable detection with high repeated measurement accuracy. The purpose is to provide.

  A laser spectroscopic inspection method according to the present invention is a laser spectroscopic inspection method in which an inspection beam irradiated from a light projecting light source is transmitted through an outer wall of a container containing a gas to be analyzed and received by a detector. The outer wall of the container through which the beam is transmitted is disposed so as to be inclined with respect to a plane orthogonal to the beam optical axis of the inspection beam, and the traveling direction of the reflected light reflected on the front and back surfaces of the outer wall is determined from the beam optical axis. The reflected light received by the detector is eliminated or reduced so as to be shifted.

  Moreover, it is preferable that the outer wall of the container has a cylindrical cross section on a plane including the beam optical axis, and the beam optical axis is displaced from the center of the internal space surrounded by the outer wall on the plane.

  Further, in the above laser spectroscopic inspection method, the container has an incident-side outer wall and an emission-side outer wall arranged in parallel to each other, and the container is arranged so that the outer wall is inclined with respect to a plane orthogonal to the beam optical axis. It is preferable to arrange.

  A laser spectroscopic inspection apparatus according to the present invention is a laser spectroscopic inspection apparatus in which an inspection beam irradiated from a light projecting light source is sequentially transmitted through a plurality of outer walls of a container containing a gas to be analyzed and received by a detector. The container is arranged such that at least an outer wall of the container through which the inspection beam passes is inclined with respect to a plane orthogonal to the beam optical axis.

  Further, in the laser spectroscopic inspection apparatus, the outer wall of the container has a cylindrical cross section on a plane including the beam optical axis, and the beam optical axis is positioned from the center of the inner space surrounded by the outer wall on the plane. It is preferable that they are arranged so as to be displaced.

  Further, in the laser spectroscopic inspection apparatus, the container is disposed such that the outer wall on the incident side and the outer wall on the emission side of the container are parallel to each other, and the outer wall is inclined with respect to a plane orthogonal to the beam optical axis. It is preferable.

  Furthermore, in the laser spectroscopic inspection apparatus, it is preferable that a container rotating device for rotating the container around the axis of the container is disposed at an inspection position where the inspection beam is irradiated onto the container.

  In addition, from the position where the beam optical axis passes through the center of the internal space in the light receiving data received by the detector, the light source and the detector, the moving device that moves at least one of the containers, and / or Alternatively, it is preferable to include a spectroscopic analyzer that analyzes the component of the gas to be analyzed based on the inspection beam that is displaced rearward in the moving direction.

  According to the laser spectroscopic inspection apparatus and the laser spectroscopic inspection method of the present invention, the outer wall of the container through which the inspection beam is transmitted is inclined with respect to the plane orthogonal to the beam optical axis. Since the reflected light reflected on the front and back surfaces of the outer wall of the glass is shifted from the beam optical axis, the detector receives or receives the inspection beam transmitted only through the gas to be analyzed in the internal space. be able to. Therefore, the inspection beam detected by the detector is not polarized, the amount of polarization does not increase or decrease, resonance or wavelength change does not occur, and the component amount, concentration, pressure, etc. of the gas to be analyzed are increased by frequency modulation spectroscopy. The analysis accuracy is high and the repeated measurement accuracy is high, and the detection can be performed stably.

  In addition, for containers such as vials with a cylindrical outer wall, an offset distance is set and the beam is displaced from the center of the internal space, so that the gas to be analyzed can be detected stably with high analytical accuracy. can do.

  Furthermore, in the case where the outer wall on the entrance side and the exit side of the inner space are parallel to each other, for example, the body is a container having a rectangular cross section, the outer wall is inclined with respect to the plane perpendicular to the beam optical axis, Can be detected stably with high analysis accuracy.

  Furthermore, by rotating the container around the center of the internal space, the gas to be analyzed can be stably detected with high analysis accuracy.

  In addition, when continuously detecting by moving the container, the inspection beam when the beam optical axis is displaced forward and / or backward in the movement direction from the position where the beam optical axis passes through the center of the internal space by the spectroscopic analyzer. Based on the above, by analyzing the gas to be analyzed in the internal space, the component amount, concentration, pressure, etc. of the gas to be analyzed in the container can be stably detected with high analysis accuracy.

It is a longitudinal cross-sectional view explaining the inspection state of the vial bottle by the laser spectroscopy inspection apparatus which concerns on this invention. It is a fragmentary sectional view of planar view explaining the inspection beam and reflected light in the head space. (A)-(b) shows the state in which the inspection beam passes through the axis of the container and the combined waveform of the inspection beam, (a) is an explanatory view showing a plane cross section showing the head space, and (b) is the inspection beam. A waveform graph showing a resonance state by reflected light, (c) is a waveform graph showing waveform deformation and period variation by an inspection beam and reflected light. It is a plane sectional view showing a laser spectroscopic inspection method concerning the present invention, and showing offset distance in head space. It is sectional drawing of the side view of the inspection equipment provided with the laser spectroscopy inspection apparatus which concerns on this invention. It is an expanded sectional view of the principal part shown in FIG. 5 by the side view. It is a top view of inspection equipment. It is a front view of an inspection facility. (A) and (b) show experimental results and experimental modes, (a) is a graph showing the relationship between the standard deviation of the measured value when the oxygen concentration is 0% and the offset distance, and (b) is the headspace of the vial. FIG. It is a graph which shows the relationship between the standard deviation of the measured value at the time of oxygen concentration 8%, and offset distance. It is a graph which shows the relationship between the standard deviation of the measured value when oxygen concentration is 20%, and offset distance. It is explanatory drawing in the case of letting an inspection beam pass through the shoulder part of an airtight container, showing other examples of a laser spectroscopy inspection method and device concerning the present invention. In Example 2 of the laser spectroscopy inspection method and apparatus concerning the present invention, it is a plane sectional view showing the irradiation state of the inspection beam to the airtight container which has the head space of the square tube section. FIG. 9 is a diagram illustrating a third embodiment of the laser spectral inspection method and apparatus according to the present invention, and is an explanatory view when a cylindrical cross-section container is inspected by an inspection beam during continuous movement. FIG. 10 is a diagram illustrating a modified example of Embodiment 3 of the laser spectral inspection method and apparatus according to the present invention, and is an explanatory view when inspecting a rectangular tube container with an inspection beam during continuous movement. (A) And (b) shows Example 4 of the laser spectroscopy inspection method and apparatus concerning this invention, (a) is explanatory drawing which shows the detection state of the culture chamber whose plane cross section is cylindrical, (b) is It is explanatory drawing which shows the detection state of the culture chamber whose plane cross section has a rectangular tube-shaped cross section. (A) And (b) shows the application example of the laser spectroscopy apparatus which concerns on this invention, (a) is explanatory drawing which shows the detection state of the accommodation tank whose plane cross section has a square cylindrical cross section, (b) is a longitudinal cross section FIG. 6 is an explanatory view showing a detection state of a cylindrical duct.

  This inspection facility analyzes a test beam (laser light) of a predetermined frequency by frequency modulation spectroscopy, and detects the component amount, concentration, pressure, etc. of the gas to be analyzed from the value of the laser light transmitted and absorbed. It is equipped with a device. The vial bottle shown here as a container is a sealed container in which a medicine for medical use or laboratory use is sealed in an inert atmosphere. The laser spectroscopic inspection apparatus according to the embodiment absorbs, for example, an inspection beam having a wavelength (763 nm) absorbed by oxygen molecules and a water molecule in a head space (internal space) where no drug is present at the upper portion of the vial from two projection light sources. A test beam having a wavelength (1400 nm) is irradiated and transmitted, and received by a detector (detector). Then, this data is analyzed by frequency modulation spectroscopy based on the peak height of the waveform, and the oxygen concentration and water content are analyzed, and the pressure (degree of vacuum) is analyzed based on the waveform width. In addition, non-destructive inspection such as nitrogen substitution rate and dryness can be performed.

  In addition, this laser spectroscopic inspection device changes the target of inspection to the gas to be analyzed in the vial, selects the wavelength of the inspection beam, and selects the wavelength of the inspection beam. Optically transparent to transmit laser light, such as petri dishes, test tubes, and incubators used for culture of tissues such as remarkable multicellular organisms and culture of microorganisms such as fungi, algae, protozoa, and bacteria It can be used for inspection of the amount of oxygen and the amount of carbon dioxide in a space portion without contents such as a sealed container, a vacuum container, and a storage container having various parts.

  Furthermore, as an application example, the gas to be analyzed can be flowed, retained, or stored in a production facility or a combustion facility, and can be applied as a device that analyzes gas components in a duct or a tank in real time.

[Example 1]
Hereinafter, Example 1 of the inspection facility equipped with the laser spectroscopic inspection apparatus according to the present invention will be described with reference to FIGS.

(container)
As shown in FIG. 1, a vial (sealed container, hereinafter referred to as container B), which is a container, encloses a medical drug C and the like, and has a mouth Bp sealed at the upper end and a container having a cylindrical cross section. The main body is provided, and at least the outer walls Bwi and Bwo of the container main body are formed of optically transparent glass that transmits the inspection beam (laser light) R1 without being absorbed or colored transparent glass that does not absorb the laser light. ing. Then, the inspection beam R1 emitted from the light projecting light source 22A (22B) passes through the head space (internal space) Bs surrounded by the outer walls Bwi and Bwo having a cylindrical section in a plan view without the contents at the upper part of the container body. Set to be transparent.

  By the way, as shown in FIG. 3A, the inspection beam R1 projected from the projection light source 22A (22B) passes through the head space Bs from the outer wall Bwi on the incident side of the container body, and further, the outer wall Bwo on the emission side. And the laser beam axis Ro of the inspection beam R1 coincides with the axis Lo that intersects the container axis Bo, which is the center of the head space Bs, at right angles when being received by the detector 23A (23B). The front and back surfaces (parallel to the front surface) of the outer walls Bwi and Bwo are perpendicular to the laser optical axis Ro. In this case, the reflected light R2 reflected from the front and back surfaces of the outer walls Bwi and Bwo on the incident side and the outgoing side, the light projecting window of the light projecting light source 22A, and the light receiving window of the detector 23A is inspected along the laser optical axis Ro. At the same time, it returns to the detector 23A and becomes a cause of disturbance. For example, when the inspection beam R1 and the reflected light R2 are combined, the amount of polarization is increased, or the waveforms of the inspection beam R1 and the reflected light R2 overlap as shown in FIG. Further, as shown in FIG. 3C, the waveform, amplitude λ, and frequency Δf are changed. For this reason, the reflected light R2 has been a factor of reducing the analysis accuracy of the inspection beam R1.

  In the first embodiment, as shown in FIG. 2, the laser optical axis Ro is shifted from the axis Lo where the laser optical axis Ro intersects the container axis Bo with an offset distance δ on a cross section in plan view including the laser optical axis Ro. To form incident angles θs1, θb1, θs2, and θb2 with respect to the front and back surfaces of the outer walls Bwi and Bwo that are orthogonal to the laser optical axis Ro, whereby the reflected light R2 reflected by the front and back surfaces of the outer walls Bwi and Bwo is formed. The direction deviates from the laser optical axis Ro, and the reflected light R2 entering the detectors 23A and 23B is eliminated or reduced.

  That is, as shown in FIG. 4 in which only the reflected light of the outer wall surface is displayed, in the case of the container B having the outer walls Bwi and Bwo having a cylindrical cross section in a plan view including the laser optical axis Ro, in Example 1, the laser optical axis The position of the laser optical axis Ro is set in the range of the offset distance δ1 or more and δ2 or less in which the laser optical axis Ro is displaced in the radial direction from the axis Lo intersecting the container axis Bo on the cross section in plan view including Ro. Thus, incident angles θ1 and θ2 with respect to the laser optical axis Ro are formed with respect to the normal lines (normal lines) of the surfaces of the outer walls Bwi and Bwo.

These incident angles θ1 and θ2 can be obtained from offset distances (outer diameter ratios) δ1 and δ2 from Sinθ1 = δ1 / 50 and Sinθ2 = δ2 / 50.
(Inspection equipment)
This inspection facility will be described with reference to FIGS. This inspection facility periodically inspects a container B (vial bottle) sampled from, for example, a chemical production line. As shown in FIG. 7, a container transport apparatus 10 that intermittently transports containers B arranged in tandem along the transport line L to inspection positions P1, P2, and lasers disposed at the inspection positions P1, P2, respectively. A laser inspection unit 20 having inspection devices 21A and 21B for performing analysis, and a container for rotating a container B stopped at two inspection positions P1 and P2 around a container axis Bo as shown in FIGS. Based on the rotation device 30, the container transport device 10, the laser inspection unit 20, the operation control device 40 with a power supply device for driving and controlling the container rotation device 30, and the inspection beam R1 detected by the inspection devices 21A and 21B. A spectroscopic analyzer 41 that detects an oxygen concentration and water content in B, a pressure (degree of vacuum), a nitrogen substitution rate, and the like, and a touch panel type operation screen 42 are provided.

  Although not described in detail, reference numeral 43 shown in FIG. 5 is an operating device for supplying nitrogen. At the inspection positions P1 and P2, a gap between the light projection windows 22A and 22B and the container B, and the container B and the detector 23A. , 23B, nitrogen gas is supplied to the gap between the light receiving windows to eliminate the influence of oxygen contained in the atmosphere and improve the analysis accuracy.

(Container transport device)
As shown in FIGS. 6 to 8, the container transport device 10 is installed on a transport holder 11 having a holder portion 12 that holds a plurality of containers B and a base frame 13, and moves the transport holder 11 along a transport line L. And a feed driving device 14 for intermittent conveyance. The feed drive device 14 is composed of, for example, a single-acting robot, a linear slider, a ball screw type drive device, or the like.

  In the transport holder 11, ten holder portions 12 are formed at regular intervals along the transport line L. As shown in FIG. 6, each holder portion 12 includes a cylindrical holding recess 12 a that holds the container B in a standing state and rotatably around the container axis Bo, and a bearing 12 d at the bottom of the holding recess 12 a. A bottom support plate 12b that can rotate around the container axis Bo via a base plate, and a passive recess 12c that engages the drive shaft of the container rotation device 30 at the bottom of the bottom support plate 12b.

(Laser inspection department)
As shown in FIGS. 5 and 8, the laser inspection unit 20 is provided with a height adjustment device including an elevating drive mechanism (for example, a ball screw type) on an inspection support frame 24 erected in the vicinity of the downstream side of the inspection position P2. 25 and a pair of left and right light projecting and light receiving sensor support frames 27S and 27R adjust the height and distance with respect to the container B via a light projecting / receiving position adjusting device 26 comprising an approach / separation drive mechanism (for example, a ball screw type). It is installed freely.

  The inspection devices 21A and 21B have the same structure, and the laser light source 22A and 22B of the semiconductor laser respectively installed on the two front light emitting sensor support frames 27S across the transport line L, and the two rear light sources. Detectors 23A and 23B that receive inspection beams (laser beams) that are respectively installed on the light receiving sensor support frame 27R and transmitted through the container B.

  Here, the inspection device 21A installed on the upstream side of the transport line L is for oxygen concentration detection, and the inspection device 21B installed on the downstream side of the transport line L is for water content detection.

(Container rotating device)
As shown in FIG. 6, the container rotating device 30 is provided with a lifting block 32 a installed over the inspection positions P <b> 1 and P <b> 2 on the output rod of the shaft elevator 32 erected and arranged at an intermediate position between the inspection positions P <b> 1 and P <b> 2. A pair of front and rear intermediate shafts 31b are erected on the elevating block 32a via bearings 31a so as to correspond to the inspection positions P1 and P2. In the two intermediate shafts 31b, a spur passive gear 33c is attached to the intermediate part, and a driving convex part 31c fitted to the passive concave part 12c is formed at the upper end part.

  A rotary drive device 33a is erected on the back side of the shaft elevator 32, and a spur drive gear 33b that meshes with each spur passive gear 33c is attached to the output shaft of the rotary drive device 33a. The spur drive gear 33b has a width wider than the lift stroke of the intermediate shaft 31b so that the spur drive gear 33b meshes within a range in which the spur passive gear 33c is lifted and lowered by the shaft elevator 32.

  Therefore, when the holder portion 12 holding the container B to be inspected is stopped at the first inspection position P1 and the second inspection position P2, the shaft elevator 32 is activated, and the drive convex portion 31c is raised and rotated. The driving device 33a is activated to rotate the intermediate shaft 31b via the spur drive gear 33b and the spur passive gear 33c. And each drive convex part 31c is each inserted in the passive recessed part 12c of both the holder parts 12, and the container B of the two holder parts 12 is rotated around the container axis Bo at a constant speed, respectively.

  Conventionally, due to the stopping accuracy of the container at the inspection position and the processing accuracy of the parts of the transport device, the positional deviation between the intermediate shaft 31b and the holder portion 12 occurs, and the driving convex portion 31c is not fitted well to the passive concave portion 12c, There is a problem that the rotation failure of the bottle B occurs or the rotation speed of the bottle B becomes uneven. However, in the first embodiment, the intermediate shaft 31b is rotatably provided on the elevating block 32a via the bearing 31a, while the bottom support plate 12b having the passive recess 12c is provided at the bottom of the holder portion 12a via the bearing 12d. It is supported by. As a result, since the inclination of the intermediate shaft 31b is absorbed by the two bearings 31a and 12d, even if the intermediate shaft 31b and the passive recess 12c are displaced, the bottle B is moved by the rotation drive device 33a. It is smoothly rotated around the center Bo. In this way, since the bottle B is rotated around the container axis Bo at a constant speed, the measurement error due to the container thickness error can be averaged, so that a stable detection value can be obtained and repeated measurement accuracy can be improved. Can be high.

(Experimental example)
9 to 11 are experimental graphs obtained by measuring three types of vials (containers) in which the oxygen concentration is set to 0%, 8%, and 20% using the above inspection equipment. Here, the horizontal axis represents the offset distance (outer diameter ratio%), and the vertical axis represents the standard deviation. The three types of vials are CASE 1 with an outer diameter of 30.2 mm, outer wall thickness of 1.5 mm (inner diameter 27.2 mm), CASE 2 with an outer diameter of 24.3 mm, outer wall thickness of 1.2 mm (inner diameter of 21.9 mm), CASE 3 Then, the outer diameter is 18.0 mm and the thickness of the outer wall is 1.0 mm (inner diameter 16.0 mm).

  In the experiment, an inspection beam having a wavelength (763 nm) at which oxygen molecules are absorbed from the light projecting light source 22B is irradiated and transmitted through the headspace Bs of the vial for 10 seconds, and this is received by the detector 23B. At the time of measurement, each vial was rotated around the container axis Bo. Then, the oxygen concentration was analyzed based on the peak height of the waveform by frequency modulation spectroscopy, and the standard deviation was obtained from the measurement data for 10 times.

(Offset distance)
Referring to FIGS. 9 to 11 respectively, when the offset distance δmin (δ1) is 0% and its vicinity, and the inspection beam R1 passes through the axis Lo and its vicinity, the standard deviation is high and the repeated measurement accuracy is low. Recognize. This tendency spreads until the offset distance δmin is in the range of about 10% of the outer diameter of the container. It can also be seen that the standard deviation is low when the offset distance δmax (δ2) is between 30% and 40%, and the repeated measurement accuracy is improved. When the offset distance exceeds 30% to 40%, the standard deviation increases again.

  By the way, it is presumed that the lower the oxygen concentration, the more oxygen molecules decrease. Therefore, it is presumed that the analysis accuracy is low and the variation in the detection value is likely to increase, but this tendency is not observed in this experiment. However, CASE 1 with a large container outer diameter has a wide range of low standard deviations corresponding to the offset distances δmin and δmax compared to CASE 2 and CASE 3 with small container outer diameters, and repeatability is high. This is considered to be because even if the offset distances δmin and δmax are increased, if the outer diameter of the container (the inner diameter of the head space Bs) is large, a sufficient transmission distance Ls is secured. Therefore, in the case of a vial with a large outer diameter such as an outer diameter of 75 mm, it is assumed that the offset distance δmin−δmax is wide, the standard deviation is low, the repeatability is high, and the measurement range is wide. Is done.

  The offset distances (outer diameter ratio%) δmin and δmax are shown in Table 1 and the incident angles θmin and θmax of the inspection beam R1 are shown in Table 2 below. The transmission distances Ls.min and Ls.max (outer diameter ratio%) of R1 are shown in Table 3.

  (Offset distance)

  For example, when the outer diameter of the container B is about 15 to 30 mm, as shown in Table 1, the range of the offset distance (outer diameter ratio%) where the standard deviation is 0.050 or less is δmin = ± 8% or more in CASE1, δmax = ± 38% or less, and in CASE3, δmin = ± 11% or more and δmax = ± 32.5% or less. Therefore, in consideration of the experimental values, the offset distances (outer diameter ratio%) δmin, δmax are suitable values within the range of 8% to 30% with respect to the container outer diameter. It turns out that it will be 10% or more and 25% or less with respect to a container outer diameter.

  As described above, by setting appropriate offset distances δmin and δmax corresponding to the outer diameter (or inner diameter) of the container, measurement can be performed with high analysis accuracy, and variation can be increased with little variation.

  In the CASE 2 experiment, it is shown that the deviation is low and the variation is large at the detection value of the offset distance δmin = −12% regardless of the oxygen concentration. There may be a deviation in Ro or other trouble has occurred.

  (Angle of incidence)

  As shown in Table 2, based on the offset distances δmin and δmax, the incident angles θmin and θmax of the laser optical axis Ro with respect to the normal (normal) of the outer wall (surface) are expressed as sinθmin = δmin / 50 and sinθmax = δmax / 50. Can be sought. When the outer diameter of the container B is about 15 to 30 mm, the incident angle at which the standard deviation is 0.050 or less is θmin = ± 9.2 ° or more and θmax = 49.5 ° or less in CASE1, and CASE3 It can be seen that θmin = ± 12.7 ° or more and θmax = ± 40.5 ° or less.

  Therefore, from this experimental result, the incident angles θmin and θmax of the laser optical axis Ro with respect to the normal lines of the outer walls Bwi and Bwo are in the range of 9 ° or more and 50 ° or less as preferable values, and 15 ° or more as optimal values. The range is 35 ° or less.

  In addition, when the thickness of an outer wall is thin with respect to a container outer diameter here, since the difference of the reflection angle of an outer wall surface and an outer wall back surface becomes small, it becomes substantially the same.

  (Transmission distance)

  For example, when the container outer diameter is about 15 to 30 mm and the standard deviation is 0.050, the minimum transmission distance Ls.min with respect to the inner diameter is 65.0% for CASE 1 and 73.3% for CASE 2. CASE 3 shows 76.0%. Therefore, from this experiment, the inner diameter ratio of the transmission distance Ls.min is 65% or more as a suitable value and 76% or more as an optimum value.

  By the way, with respect to the offset distances δmin and δmax, the factor that the standard deviation decreases due to the decrease in the transmission distance Ls of the head space Bs depends on the size of the container B (head space Bs). For example, in a vial with an outer diameter of 75 mm, the permeation distance Ls.min is sufficiently long, so that the standard deviation distribution is further flat and the permeation distance Ls (min) is 30% or more of the inner diameter of the container. It is estimated that stable measurement with analytical accuracy is possible. On the other hand, when the syringe syringe is used as a sealed container instead of a vial, the inner diameter of the container is about 8 mm, so that the standard deviation is low, and there is a possibility that detection with a lot of variation with low analysis accuracy is possible. Therefore, in this case, it is considered necessary to ensure a transmission distance Ls.min of at least 80 to 90% of the inner diameter of the container.

  Here, when the thickness of the outer wall is thin relative to the outer diameter of the container, the transmission distance with respect to the inner diameter and the transmission distance with respect to the outer diameter are substantially the same.

(Summary of experiment)
From the above experimental results, for example, in the case of a vial with a cylindrical cross section having an outer diameter of about 15 to 30 mm, the offset distance (outer diameter ratio) δmin to δmax is preferably 8% or more and 30% as an outer diameter ratio. The following ranges are preferable, and the optimal value is preferably a range of 10% or more and 25% or less in terms of outer diameter ratio.

  The incident angles θmin to θmax of the beam optical axis Ro with respect to the perpendiculars of the outer walls Bwi and Bwo are preferably in the range of 9 ° to 50 ° as a preferred value, and preferably in the range of 15 ° to 35 ° as the optimum value. .

  Furthermore, the permeation distance Ls.min with respect to the outer diameter of the container B is preferably secured at 65% or more as a suitable value, and more preferably 76% or more as an optimum value.

(Effect of Example)
According to the first embodiment, the outer walls Bwi and Bwo of the container B through which the inspection beam R1 is optically transmitted can be formed by shifting the inspection beam R1 from the axis Lo within a range of δ1 and δ2 with an appropriate offset distance. The reflected light R2 reflected from the front and back surfaces of the outer walls Bwi and Bwo of the container B is transmitted when the inspection beam R1 that is inclined with respect to the plane orthogonal to the optical axis Ro and irradiated from the light projecting light source 22A (22B) is transmitted. Deviated from the axis Bo. Therefore, the reflected light R2 received by the detector 23A (23B) is eliminated or reduced, and the inspection beam R1 transmitted only through the gas to be analyzed in the head space Bs can be received. As a result, the inspection beam R1 detected by the detector 23A (23B) is not polarized, the amount of polarization is increased or decreased, and resonance or wavelength change does not occur. Concentration, pressure, etc. can be measured with high analytical accuracy and repeated measurement accuracy.

  Further, in the case of the container B having outer cylindrical surfaces Bwi and Bwo having a cylindrical cross section, by arranging the beam optical axis Ro within the range of the offset distances δ1 and δ2 from the container axis Bo of the head space Bs, the gas to be analyzed can be analyzed with high accuracy. It can be detected and analyzed stably. Furthermore, by rotating the container B around the container axis Bo, the gas to be analyzed can be stably detected with higher analysis accuracy.

  In the first embodiment, the offset distances δ1 and δ2 and the incident angles θ1 and θ2 on the cross section in plan view through which the inspection beam R1 passes are described. However, as shown in FIG. 12, for example, the inspection beam R1 Transmits the shoulder (inclined portion) of the container B across the container axis Bo, and has incident angles γ1 and γ2 with respect to the normal of the outer walls Bwi and Bwo in the longitudinal sectional view with respect to the inspection beam R1. You may make it let. In this case, the transmission distance Ls tends to be short, and it is necessary to ensure a sufficiently long transmission distance Ls.

[Example 2]
As shown in FIG. 13, at the inspection positions P1 and P2, the inspection beam R1 is transmitted through the head space Bs surrounded by at least the outer walls Bwi and Bwo that are parallel to each other, for example, a rectangular container B1 (container) ) With respect to the beam optical axis Ro of the inspection beam R1, the angle of incidence θ1, θ2 with respect to the normal of the outer walls Bwi, Bwo is inclined by tilting the rectangular container B1 around the container axis Bo within a predetermined angle range. May be formed. The incident angles θ1 and θ2 can be referred to the data in Table 2 in the experiment of Example 1. Of course, it is not necessary to intersect the beam optical axis Ro with the container axis Bo.

  That is, in the data of Table 2, in the case of the container B having a cylindrical cross section, the incident angles θ1 and θ2 of the laser optical axis Ro with respect to the normal lines (normal lines) of the outer walls Bwi and Bwo have preferable values of 9 ° or more and 50 The optimum value is 15 ° or more and 35 ° or less. Therefore, the incident angle θ of the rectangular container B1 is preferably 9 ° or more and 50 ° or less, and more preferably 15 ° or more and 35 ° or less.

  Thereby, when the inspection beam R1 is transmitted, the reflected light R2 reflected on the front and back surfaces of the outer walls Bwi and Bwo of the rectangular container B1 is reflected in a direction deviating from the beam optical axis Ro, so that it is reflected on the detectors 23A and 23B. The reflected light R2 that is received is eliminated or reduced, and the component amount, concentration, pressure, etc. of the analyte gas in the head space Bs are highly analyzed with high accuracy and stable by frequency modulation spectroscopy. Can be measured.

  In the case of the rectangular container B1, since the transmission distance Ls in the head space Bs is not increased or decreased by inclining the rectangular container B1 around the container axis Bo, the container having a cylindrical cross section. Compared to B, the standard deviation of the detected value becomes flatter.

[Example 3]
In Example 1, the intermittently transported container B was temporarily stopped at the inspection positions P1 and P2, and the inspection beam R was irradiated and detected. In Example 3, as shown in FIG. 14, the container B is continuously transported, and while the container B passes through the inspection positions P1 and P2, the inspection beam R1 is irradiated and the gas to be analyzed in the head space Bs is irradiated. To detect.

  In this case, the inspection beam R1 is radiated to the head space Bs of the container B continuously from the projection light source 22A (22B) to the container B moving in the inspection positions P1 and P2 at a constant speed over the entire cross section in a plan view. Then, the light is received by the detector 23A (23B). At this time, in the spectroscopic analyzer 41, data of the inspection beam R1 is acquired over the entire outer diameter of the container B received by the detector 23. Of this data, the beam optical axis Ro is the container axis of the head space Bs. From the axis Lo passing through the center Bo, data of one or both of the inspection beams R1 of at least a range Δ1 displaced in a predetermined range ahead of the moving direction and a range Δ2 displaced in a predetermined range rearward of the moving direction is selected. Thus, the gas to be analyzed in the head space Bs is analyzed.

  Here, the data of the offset distances δ1 and δ2 in Table 1 can be referred to for the range Δ1 ahead of the moving direction and the range Δ2 behind the moving direction. That is, for example, when the outer diameter of the container is about 15 to 30 mm, the front range Δ1 is an outer diameter ratio of 30% or less and a range of 8% or more, and the rear appropriate range Δ2 is an outer diameter ratio of 8% or more and 30%. The following range is preferable, and the front range Δ1 is the optimal range of the outer diameter ratio of 25% or less and 10% or less, and the rear range Δ2 is the optimal range of the outer diameter ratio of 10% or more and 25% or less. I can say that.

  Of course, by rotating the container B around the container axis Bo while moving the inspection positions P1 and P2, it is possible to obtain a stable detection value with higher analysis accuracy and without any variation.

  In Example 3, the light projecting light source 22A (22B) and the detector 23A (23B) are fixed and the container B is moved, but the light source 22A (22B) and the detector 23A ( 23B) may be moved in synchronization with each other.

  As shown in FIG. 15, when the rectangular container B1 is moved, even if the inspection beam R1 is transmitted through the container axis Bo and its vicinity at the inspection positions P1 and P2, the incident angle θ becomes uniform, so that it is repeated. Measurement accuracy is not reduced. Table 2 can be referred to for the incident angles θ1 and θ2 at this time. Therefore, the suitable values of the incident angles θ1 and θ2 are 9 ° or more and 50 ° or less, and the optimum values are 15 ° or more and 35 ° or less. The rectangular container B1 is arranged to be inclined around the container axis Bo so that the incident angles θ1 and θ2 are obtained, and data of the inspection range Δ in which the incident angle does not vary is selected, and the spectral analysis is performed based on the inspection range Δ. Can be inspected.

[Example 4]
In Example 1, the container is a vial. However, as shown in FIGS. 16 (a) and 16 (b), for example, a petri dish, a test tube, an incubator, etc. used for culturing microorganisms and fungi is irradiated with laser light. It can also be set as the vacuum containers (containers) B2 and B3 which have the optically transparent part which permeate | transmits.

  As shown in FIG. 16 (a), in the case of the vacuum vessel B2 in which the planar view surrounded by the optically transparent outer wall Bw forms a culture chamber Bs with a cylindrical cross section, it is predetermined from the vessel axis Bo of the vacuum vessel B2. The projection light source 22, the laser optical axis Ro, and the detector 23 may be installed so that the inspection beam R1 is transmitted with a position shift of the offset distance δ. Table 1 can be referred to for the offset distance Δ at this time. The offset distance δ is preferably 8% or more and 30% or less in terms of the outer diameter ratio, and is optimally 10% or more and 25% or less in terms of the outer diameter ratio. If a sufficient transmission distance Ls can be secured, stable detection can be performed in a wider range.

  As shown in FIG. 16 (b), in the case of the rectangular vacuum vessel B3 in which the culture chamber Bs having a rectangular tube cross section having the optically transparent monitoring window (outer wall) Bw on the outer walls parallel to each other is shown in Example 2. Similarly, the incident angle θ of the laser optical axis Ro with respect to the normal line on the front surface and the back surface of the monitoring window Bw is formed. The incident angle θ at this time can be referred to the data in Table 2. Therefore, the preferable value of the incident angle θ with respect to the perpendicular of the monitoring window Bw is 9 ° or more and 50 ° or less, and the optimum value is 15 ° or more and 35 ° or less. Thereby, the reflected light reflected on the front and back surfaces of the monitoring window Bw is eliminated or reduced, and the component amount, concentration, pressure, etc. of the gas to be analyzed in the culture chamber Bs are measured with high analytical accuracy and repeated measurement accuracy. Is high and can be measured stably and efficiently.

[Application example]
In the above Examples 1 to 4, the analysis target gas sealed in a vial, a sealed container, or a vacuum container was used as an inspection object. However, as an application example, it is discharged from a production facility, a manufacturing apparatus, a combustion engine, a combustion furnace, or the like. The present invention can be applied to a laser light spectroscopic inspection apparatus that inspects a gas to be analyzed such as a generated gas or exhaust gas in real time.

  That is, as shown in FIG. 17A, for example, a detection tank T having a rectangular cross-section for temporarily retaining the gas to be analyzed is provided in a gas duct, and an optically transparent monitor is provided on the outer walls parallel to each other. The window Tw is formed, and the incident angle θ of the laser optical axis Ro with respect to the normal to the front surface and the back surface of the monitoring window Tw is formed as in the second and fourth embodiments. The incident angle θ can be referred to the data in Table 2. That is, the suitable value of the incident angle θ with respect to the vertical line of the monitoring window Tw is 9 ° or more and 50 ° or less, and the optimum value is 15 ° or more and 35 ° or less. As a result, the reflected light reflected on the front and back surfaces of the monitoring window Tw is eliminated or reduced, and the component amount, concentration, pressure, etc. of the gas to be analyzed in the tank T can be analyzed with high accuracy and repeated measurement accuracy. High, stable and efficient measurement.

  In addition, as shown in FIG. 17B, when applied to a laser spectroscopic inspection apparatus that inspects a gas to be analyzed that passes through a gas duct D having a cylindrical cross section, an optically transparent portion is opposed to the outer wall of the gas duct D. A monitoring window Dw is formed. Then, the light projecting light source 22, the laser optical axis Ro, and the detector 23 are installed so that the inspection beam R1 is transmitted through the space Ds of the gas duct D with a predetermined offset distance δ from the axis Do. That's fine.

  The offset distance δ at this time can be referred to the data in Table 1. Accordingly, the preferred range of the offset distance δ is preferably 8% or more and 30% or less in terms of the outer diameter ratio of the gas duct D, and the optimum range is 10% or more and 25% or less in terms of the outer diameter ratio, but the inner diameter of the gas duct D is large. If a sufficient transmission distance Ls can be ensured, stable detection can be performed in a wider range.

δ1, δ2 Offset distance θ1, θ2 Incident angle Δ1 Front range Δ2 Rear range B Container (vial bottle)
Bs Headspace Bwi Incident side outer wall Bwo Emission side outer wall P1, P2 Inspection position L Transport line Lo Axis R1 Inspection beam R2 Reflected light Ro Beam optical axis 10 Container transport device 11 Transport holder 12 Holder unit 13 Base frame 14 Feed drive Device 20 Laser inspection unit 21A, 21B Inspection device 22A, 22B, 22 Projection light source 23A, 23B, 23 Detector 24 Inspection support frame 25 Height adjustment device 26 Projection / reception position adjustment device 30 Container rotation device 40 Operation control device 41 Spectroscopy Analyzer 42 Operation screen 43 Nitrogen supply controller

Claims (8)

A laser spectroscopic inspection method in which an inspection beam irradiated from a light projecting light source is transmitted through an outer wall of a container containing a gas to be analyzed and received by a detector,
At least an outer wall of the container through which the inspection beam is transmitted is disposed so as to be inclined with respect to a plane perpendicular to the beam optical axis of the inspection beam;
The laser spectroscopic inspection method, wherein the traveling direction of the reflected light reflected on the front and back surfaces of the outer wall is shifted from the beam optical axis to eliminate or reduce the reflected light received by the detector. The laser spectroscopic inspection method according to claim 1,
The outer wall of the container has a cylindrical cross section on a plane containing the beam optical axis;
The laser beam spectroscopic inspection method, wherein the beam optical axis is displaced from the center of the internal space surrounded by the outer wall on the plane. The laser spectroscopic inspection method according to claim 1,
The container has an outer wall on the incident side and an outer wall on the outgoing side that are arranged in parallel to each other,
A laser spectroscopic inspection method characterized in that the container is arranged so that the outer wall is inclined with respect to a plane orthogonal to the beam optical axis. A laser spectroscopic inspection apparatus in which an inspection beam irradiated from a light projecting light source is sequentially transmitted through a plurality of outer walls of a container containing a gas to be analyzed and received by a detector,
The laser spectroscopic inspection apparatus, wherein the container is arranged so that at least an outer wall of the container through which the inspection beam passes is inclined with respect to a plane orthogonal to the beam optical axis. The laser spectroscopic inspection device according to claim 4,
The outer wall of the container has a cylindrical cross section on a plane containing the beam optical axis;
The laser spectroscopic inspection device, wherein the beam optical axis is arranged so as to be displaced from a center of an internal space surrounded by the outer wall on the plane. The laser spectroscopic inspection device according to claim 4,
The outer wall on the incident side and the outer wall on the output side of the container are parallel to each other,
A laser spectroscopic inspection apparatus characterized in that a container is arranged such that the outer wall is inclined with respect to a plane orthogonal to a beam optical axis. The laser spectroscopic inspection device according to claim 5,
A laser spectroscopic inspection apparatus, wherein a container rotating device that rotates the container around the axis of the container is disposed at an inspection position where the inspection beam is irradiated onto the container. The laser spectroscopic inspection device according to any one of claims 4 to 7,
A light source and a detector, and a moving device for moving at least one of the containers;
Of the received light data received by the detector, the component of the gas to be analyzed is determined based on the inspection beam that is displaced forward and / or backward in the movement direction from the position where the beam optical axis passes through the center of the internal space. A laser spectroscopic inspection device comprising: a spectroscopic analysis device for analysis.

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