JP2023085941A - Laser raman spectroscopic analysis method and manufacturing method for ceramic product with feedback of obtained result - Google Patents

Abstract

To provide a laser Raman spectroscopic analysis method capable of preventing the generation of stray light to perform highly sensitive analysis when detecting and analyzing an angle of scattered light with respect to laser incident light at a direction of 90° for an opaque sample, in the laser Raman spectroscopic analysis method.SOLUTION: A laser Raman spectroscopic method comprises: irradiating an analysis surface W1 formed on a plane of a sample W, which is an opaque body, with a laser beam as incident light; passing scattered light generated from the sample through a condensing lens that is arranged at an angle of 90° to an optical axis of the incident light and whose main surface is parallel to the optical axis of the incident light; and converting the scattered light into a spectrum after spectroscopy and detection, thereby performing analysis, where an inclination angle of an analysis surface of the sample with respect to the incident light is less than 1/2 of an angle formed by a line connecting a center of a main surface of the condensing lens and an edge part of the main surface of the condensing lens, and a line connecting an intersection between the analysis surface of the sample and the optical axis of the incident light and the end part of the main surface of the condensing lens.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to a laser Raman spectroscopic analysis method and a ceramic product manufacturing method using the results obtained therefrom as feedback, and in particular, a laser Raman spectroscopic analysis method suitable for analyzing opaque bodies and a ceramic product manufacturing method using the results obtained therefrom as feedback. Regarding.

When a substance is irradiated with an electromagnetic wave such as visible light, Rayleigh scattered light having the same frequency as that of the irradiated electromagnetic wave and Raman scattered light having a different frequency are generated. Raman scattered light appears at a frequency shifted from the frequency of the irradiated electromagnetic wave, based on the vibration and rotation of the bonding state that constitutes the substance. The shift in the frequency of the Raman scattered light (Raman shift) depends on the bond energy between atoms. Therefore, laser Raman spectroscopy can be widely used for qualitative and quantitative analysis of molecules, bonding states, functional groups, etc., by creating a spectrum with this shift in frequency as the horizontal axis.
Further, laser Raman spectroscopy uses laser light as incident light, and since the wavelength of the incident light can be narrowed down to about 1 μm, it is a useful measuring means even for minute areas.

In laser Raman spectroscopy, 90° and 180° are mainly used as the detection angles of scattered light with respect to incident light.
When the detection angle is 180°, the incident light and the scattered light are coaxial. Therefore, for example, a microscope lens is arranged on the optical axis, and the incident light is irradiated and the scattered light is detected through the microscope lens. be able to. It is widely used mainly in microscopic Raman spectroscopic analyzers capable of measuring minute areas of 10 μm or less.

However, when measuring a size larger than a minute area (10 to 1000 μm level) such as discoloration or foreign matter that can be observed with the naked eye at a detection angle of 180°, the focus of the microscope lens must be widened. , there was a technical problem that a decrease in sensitivity was unavoidable.

On the other hand, when the detection angle is 90°, the incident light and scattered light are not coaxial when measuring a discoloration or foreign matter that can be observed with the naked eye, or a size larger than a minute area (10 to 1000 μm level). A stronger output can be set, and a further increase in sensitivity can be achieved.

Further, when the detection angle is 90°, if the sample is a transparent material such as glass, the incident light can pass through the sample, so this method is particularly useful.
However, if the sample is opaque, it cannot transmit incident light. Therefore, it is necessary to incline the analysis surface of the sample at an appropriate angle with respect to the incident light so as to avoid detection of reflection of the incident light (reflected light).
Regarding the sensitivity, as shown in FIG. 10A, when the tilt angle of the analysis plane W1 of the sample W with respect to the optical axis of the incident light L1 is decreased, the irradiation area on the analysis plane W1 becomes large, and the aperture 14 The area of scattered light that can pass through is smaller than the illuminated area, resulting in lower sensitivity.

On the other hand, as shown in FIG. 10(b), when the tilt angle of the analysis surface W1 of the sample W with respect to the optical axis of the incident light L1 is increased, the irradiation area on the analysis surface W1 becomes smaller and the light passes through the diaphragm 14. The resulting scattered light area occupies a larger area relative to the illuminated area, resulting in higher sensitivity.
That is, the closer the tilt angle of the analysis surface W1 of the sample W is to the vertical, the larger the area through which the scattered light passes with respect to the area irradiated with the incident light, and high-sensitivity detection and analysis can be expected.

However, as shown in FIG. 10(b), if the tilt angle of the analysis surface W1 of the sample W is brought close to perpendicular to the optical axis of the incident light, the shape changes from a perfect circle to an ellipse when viewed from the aperture 14. The area where the information is detected becomes larger than the assumed area, and there is a possibility that even unnecessary information may be detected. In such a case, by reducing the diameter of the diaphragm 14, it is possible to suppress an increase in the area of the measurement region and detect only the necessary information of the analysis site.

As described above, when the sample W is an opaque body and the scattered light detection angle is 90° with respect to the incident light L1, the closer the tilt angle of the analysis plane W1 of the sample W to the optical axis of the incident light L1 is, the more , and high sensitivity can be expected.
However, as shown in FIG. 10B, when the analysis surface W1 of the sample W is brought closer to the incident light L1 perpendicularly, the incident light reflected by the sample (reflected light L2) enters the condenser lens 13 on the detection side. , is condensed together with the scattered light that should be detected by the condensing lens 13, passes through the diaphragm 14, and is separated and detected, thereby eliminating stray light (unnecessary reflection and scattering of light occurring inside the optical system). There was a problem that occurred. The presence of this stray light causes detection of peaks that should not have been detected, deformation of the spectrum, and the like, and these phenomena lead to erroneous determination of measurement results.

In order to prevent the stray light in the laser Raman spectroscopic analysis method, Patent Document 1 discloses a configuration in which 2 to 8 dichroic mirrors that transmit Raman scattered light are installed to attenuate the reflected light and remove the stray light. there is
Further, Patent Document 2 discloses a configuration in which a diaphragm is provided on the detection optical path of near-field light, and this diaphragm removes stray light as much as possible.

JP-A-1-287448 JP-A-2004-37158

However, the configuration disclosed in Patent Literature 1 has a problem that it cannot be easily applied because the configuration of the device is large and the cost of the equipment is high.
Moreover, the configuration disclosed in Patent Document 2 cannot prevent the generation of stray light itself, and there is a problem that even if stray light is removed as much as possible, stray light components are included in the detection light path.

The present invention has been made under the above circumstances, and its object is to detect and analyze the angle of scattered light with respect to the laser incident light in the direction of 90 ° for an opaque sample in laser Raman spectroscopic analysis. The object of the present invention is to provide a laser Raman spectroscopic analysis method capable of preventing the generation of stray light and performing highly sensitive analysis, and a method of manufacturing ceramics products by feeding back the results obtained therefrom.

The laser Raman spectroscopic analysis method according to the present invention, which has been made to solve the above problems, irradiates a laser beam as incident light onto an analysis surface formed on a plane on a sample, which is an opaque body, and emits scattered light generated from the sample. Laser Raman spectroscopy, in which analysis is performed by spectroscopy and detection after passing through a condensing lens arranged in a direction of 90° with respect to the optical axis of the incident light and having a main surface parallel to the optical axis of the incident light. In the analysis method, the inclination angle of the analysis surface of the sample with respect to the incident light is defined by a line connecting the center of the principal surface of the condenser lens and the edge of the principal surface of the condenser lens, and the analysis surface of the specimen. and the optical axis of the incident light, and the line connecting the edge of the main surface of the condenser lens, the angle formed by the line is less than 1/2.
In addition, it is desirable that the angle of inclination of the analysis surface of the sample with respect to the incident light is 15° or more.
Moreover, it is desirable to use a sample having a visible light transmittance of 10 ⁻⁴ % or less as the sample.
Moreover, it is desirable that the diameter of the incident light is 10 μm or more and 100 μm or less.

Thus, in the laser Raman spectroscopic analysis method according to the present invention, the angle of inclination of the analysis surface of the sample with respect to the laser incident light is the line connecting the center of the main surface of the condenser lens and the edge of the main surface of the condenser lens. , is set to be less than 1/2 of the angle formed by the line connecting the intersection of the analysis surface of the sample and the optical axis of the incident light and the line connecting the edge of the main surface of the condenser lens. , the reflected light does not pass through the condensing lens, thereby preventing the occurrence of stray light.
Furthermore, by setting the angle of inclination of the analysis surface of the sample to incident light to 15° or more, a sufficient amount of light per unit area on the analysis surface can be obtained, enabling stable and highly sensitive measurement.

Further, the method for manufacturing a ceramic product according to the present invention, which has been made to solve the above problems, is characterized by feeding back the analysis results obtained by the above laser Raman spectroscopic analysis.

By evaluating opaque ceramic materials such as alumina, yttria, silicon carbide, carbon, etc., according to the present invention, highly sensitive evaluation can be performed without the influence of stray light. Development and provision of ceramics products becomes possible.
Furthermore, by feeding back the measurement results of the laser Raman spectroscopic analysis method of the present invention to the manufacturing conditions, it becomes possible to manufacture higher quality ceramic products.

According to the present invention, in laser Raman spectroscopic analysis, when an opaque sample is analyzed by detecting the angle of scattered light with respect to laser incident light at a direction of 90 °, stray light is prevented from occurring and high sensitivity is achieved. It is possible to provide a laser Raman spectroscopic analysis method that can be analyzed and a method of manufacturing a ceramic product that feeds back the results obtained there.

FIG. 1 is a block diagram of a laser Raman spectroscopic analysis apparatus to which the laser Raman spectroscopic analysis method of the present invention can be applied. FIG. 2 is a schematic side view for explaining the tilt angle of the analysis plane in the laser Raman spectroscopic analysis method of the present invention. FIG. 3 is a block diagram of the laser Raman spectroscopy method of the present invention. 4(a) and 4(b) are graphs showing the results of Experiment 1 in the example. FIG. 5 is another graph showing the results of Experiment 1 in the example. FIG. 6 is a graph showing the results of Experiment 2 in the example. 7A and 7B are schematic side views for explaining Experiment 2 in Example 2. FIG. 8A and 8B are graphs showing the results of Experiment 3 in the example. FIG. 9 is a graph showing the results of Experiment 4 in Example. 10(a) and 10(b) are side views showing the relationship between the tilt angle of the analysis surface of the sample with respect to the incident light and the irradiation area.

An embodiment of a laser Raman spectroscopic analysis method according to the present invention and a method of manufacturing a ceramic product in which the results obtained therefrom are fed back will be described below. The laser Raman spectroscopic analysis method according to the present invention is a method for analyzing an opaque sample, in which the sample is irradiated with laser light as incident light, and the scattered light generated from the sample is oriented at an angle of 90° to the optical axis of the incident light. is detected from the direction of In the present embodiment, the opaque sample is a sample that does not transmit light, specifically, a substance with visible light (380 to 780 mm) transmittance of 10 ⁻⁴ % or less.
The reason why the scattered light generated from the sample is detected from the direction of 90° with respect to the optical axis of the incident light is that the incident light and the scattered light are not coaxial as in the case where the detection angle is 180°. This is because the detection of the reflection (reflected light) can be avoided, and analysis with higher sensitivity is possible.

FIG. 1 is a block diagram of a laser Raman spectroscopic analysis apparatus to which the laser Raman spectroscopic analysis method of the present invention can be applied. A laser Raman spectroscopic analysis method according to the present invention is performed by a laser Raman spectroscopic analysis apparatus 11 as shown in FIG. As shown in the figure, the laser Raman spectroscopic analyzer 11 irradiates a sample W with laser light and includes an incident light optical system 12 including a laser having a specific wavelength, and a condenser lens for condensing the Raman scattered light from the sample W. 13, an aperture 14 that adjusts the amount of light that has passed through the condenser lens 13, a spectroscope 15 that splits the light that has passed through the aperture 14 into wavelengths, and a detector that detects the light split by this spectroscope 15. a vessel 16;

The condensing lens 13 is formed, for example, with a diameter of 4 cm, and its main surface (the surface including the line EF in FIG. 2) is arranged parallel to the optical axis of the incident light L1 from the incident light optical system 12, It is arranged to detect the scattered light L3 in a direction of 90° to the incident light L1.
Further, the analysis surface W1 of the sample W on which the laser light is incident is arranged so as to be inclined at an angle θ with respect to the incident light. This angle θ is determined as follows. As shown in FIG. 2, if A is the laser optical axis on the laser device 12 side, B is the intersection of the analysis surface W1 of the sample W and the optical axis of the incident light L1, and C is the inclined lower end of the analysis surface W1 of the sample W, , the inclination angle θ of the analysis surface W1 of the sample W with respect to the incident light L1 is ∠ABC. Also, if the inclined upper end of the analysis surface W1 of the sample W is D, and the front of the laser beam axis is H, ∠DBH is the opposite vertical angle of ∠ABC, and its magnitude is the angle θ.

Further, when the orthogonal direction to the analysis plane W1 of the sample W is I, and the tip of the optical axis of the reflected light L2 is G, the angle of incidence and the angle of reflection are equal, so that ∠ABI=∠GBI. Also, since ∠CBI=∠DBI=90°, ∠ABC=∠DBG=θ. Therefore, ∠HBG=2θ.

On the other hand, E is the center of the principal surface of the condenser lens 13, F is the edge of the principal surface of the condenser lens 13, and a line EF connecting E and F and a line BF connecting B and F are formed. Assuming that ∠EFB is an angle γ, since the straight line AH (incident optical axis) and the straight line EF are parallel, ∠HBF is an alternate angle of ∠EFB, and its magnitude is the angle γ.
Therefore, if γ>2θ (that is, θ is less than 1/2γ), the reflected light L2 does not enter the collecting lens on the detection side, and the reflected light L2 is collected by the collecting lens 13 together with the scattered light L3. never That is, unnecessary light does not pass through the diaphragm 14 and is detected by the spectroscope 15 and the detector 16, thereby preventing stray light (reflection and scattering of unnecessary light).
Specifically, in the present embodiment, the angle θ is 15° or more and less than 1/2γ. This is because, when the tilt angle θ is smaller than 15°, the irradiation area of the incident light L1 with respect to the sample W becomes large and the analysis sensitivity becomes low. Moreover, when the inclination angle θ is 15° or more, it is possible to sufficiently secure the analytical sensitivity.

In the laser Raman spectroscopic analyzer 11 configured as described above, the incident light optical system 12 generates laser incident light having a diameter of, for example, 10 μm or more and 100 μm or less (step S1 in FIG. 3). A laser beam with a wavelength of 532 nm is incident (step S2 in FIG. 3).
A laser beam (incident light L1) incident on the analysis surface W1 of the sample W is divided into reflected light L2 and scattered light L3. Here, the inclination angle θ of the analysis surface W1 of the sample W with respect to the laser incident light is determined by the principal surface center E of the detection side condenser lens 13, the principal surface edge F of the detection side condenser lens 13, and the sample W is set to be less than 1/2 of ∠EFB defined by the intersection point B between the analysis plane W1 and the incident light optical axis. As a result, the reflected light L2 of the incident laser light L1 does not pass through the condensing lens 13, thereby preventing the generation of stray light.
Also, the inclination angle θ is set to 15° or more. As a result, the irradiation area of the incident light L1 with respect to the single sample W is reduced, a sufficient amount of light for analyzing an opaque sample can be obtained, and a sufficient analytical sensitivity can be obtained.

The Raman scattered light L3, which has passed through the condenser lens 13 and has a wavelength different from the wavelength of the laser light, passes through the aperture 14 only the information of the portion to be measured. The Raman scattered light that has passed through the diaphragm 14 is sent to the spectroscope 15, and the Raman scattered light is separated by wavelength in this spectroscope 15 (step S3 in FIG. 3).
Signals of the Raman scattered light for each wavelength separated by the spectroscope 15 are detected by the detector 16 (step S4 in FIG. 3) and spectralized by a computer (step S5 in FIG. 3).

As described above, according to the embodiment of the present invention, the tilt angle of the analysis surface W1 of the sample W with respect to the laser incident light L1 is set to the center E of the detection-side condenser lens 13 and and the intersection point B between the analysis surface W1 of the sample W and the optical axis of the incident light L1 is set to be less than 1/2 of ∠EFB. can prevent the generation of stray light.
Furthermore, by setting the inclination angle of the analysis surface W1 of the sample W to the incident light to 15° or more, stable and highly sensitive measurement can be performed.

In addition, by evaluating opaque ceramic materials such as alumina, yttria, silicon carbide, carbon, etc. using the laser Raman spectroscopic analysis method of the present invention, highly sensitive evaluation in which the influence of stray light is eliminated is possible. This makes it possible to develop and provide higher quality ceramic products.
Furthermore, by feeding back the measurement results of the present invention to the manufacturing conditions, it becomes possible to manufacture higher quality ceramic products.

The laser Raman spectroscopic analysis method according to the present invention will be further described based on examples.
[Experiment 1]
In Experiment 1, in the apparatus configuration shown in FIG. An optical system with a distance between centers E of 4 cm (angle γ=60°) was constructed.
In this configuration, the tilt angle θ of the analysis surface W1 of the sample W with respect to the incident light is changed, and the S/N ratio (ratio of peak height and noise) at the analysis points (analysis point 1, analysis point 2) and the Raman spectrum change was measured.

A Si wafer was used as the sample W (the size of the sample W was 1 cm square, and the visible light transmittance was 10 ⁻⁴ % or less). The Si wafer was used as the sample W because it has high crystallinity, so a sharp peak can be obtained, and the S/N ratio, which is an index of analytical sensitivity, can be easily evaluated, and the analysis surface must be flat. , and ease of handling and sample placement.
In addition, iRHR320 manufactured by HORIBA, Ltd. was used as an apparatus. A diode-pumped solid-state laser (DPSS) was used as a laser device, and laser light with a wavelength of 532 nm, an output of 400 mW, and a diameter of 100 μm was used as incident light. Also, the integration time per time was set to 30 seconds, and the number of times of integration was set to eight.

The S/N ratio was measured for each of the tilt angles θ of 5°, 10°, 15°, 20°, 25°, 30°, 35° and 40°.
In addition, the measurement area on the analysis surface was measured with a diameter of 100 μm and a diameter of 3 mm when the angle to the incident light is 0°.

As the results of Experiment 1, FIG. 4(a) shows a graph for the case of the measurement area with a diameter of 100 μm, and FIG. .
In the graphs of FIGS. 4A and 4B, the vertical axis is the S/N ratio (au), and the horizontal axis is the tilt angle (°) of the analysis plane with respect to incident light.
The S/N ratio is the Raman spectrum graph for each tilt angle (°) of the analysis plane shown in FIG. ⁻¹ )), the signal S was the height of the Si peak (cps/s), and the noise N was determined as the standard deviation of the background signal (cps/s) at 30 cm ⁻¹ min on both sides of the Si peak.
As shown in the graphs of FIGS. 4(a) and 4(b), it was confirmed that the S/N ratio tended to increase up to an analysis plane angle of 15°. Moreover, the S/N ratio was substantially constant when the angle of the analysis plane was 15° or more and 25° or less. Moreover, when the angle of the analysis plane was greater than 25° and up to 30°, both rising and falling occurred. Also, when the angle of the analysis plane was larger than 30°, the S/N ratio decreased significantly.

Further, as shown in FIG. 5, it was confirmed that when the angles of the analysis planes were 35° and 40°, the spectrum was significantly deformed due to the influence of stray light. It is believed that this effect caused the S/N ratio to drop significantly when the angle of the analysis plane was greater than 30°.
As a result of Experiment 1 described above, it was confirmed that the angle of the analysis plane capable of preventing the occurrence of stray light and measuring with high sensitivity is 15° or more and 25° or less.
Moreover, it was confirmed that the sensitivity is greatly reduced by the influence of stray light when the angle is larger than 30°, which corresponds to half of the angle γ (60° in this experiment) shown in FIG.

Therefore, in order to verify the lower threshold of the tilt angle of the analysis surface that can be stably measured with high sensitivity, we calculated how the size of the scattered light generation area changes depending on the angle of the scattered light with respect to the incident light. bottom.
The graph in FIG. 6 shows the results. The vertical axis of the graph in FIG. 6 is the size of the scattered light generation region, and the horizontal axis is the tilt angle (°) of the analysis surface with respect to the incident light.

As shown in FIG. 6, by increasing the angle of inclination of the analysis surface with respect to the incident light, the area where the scattered light is generated (laser beam irradiation area) on the sample becomes smaller (that is, the amount of light per unit area increases). become).
The scattered light that can pass through the diaphragm is part of the scattered light generation area. The amount is expected to more than double. Similarly, when the angle is 10°, it is about 2/3 of the angle when it is 15°, so it is considered that the amount of light per unit area is about 1.5 times larger.

In other words, an increase in the amount of light per unit area means an increase in the amount of scattered light that can pass through the aperture, so an increase in sensitivity can be expected. However, when the angle is further increased, the amount of decrease in the area where scattered light is generated decreases (the amount of increase in the amount of light per unit area decreases). , the S/N ratio is considered to be nearly constant.
From the calculation results, it was confirmed that an inclination angle of 15° of the analysis surface with respect to the incident light is the lower limit threshold for stable and highly sensitive measurement.

[Experiment 2]
In Experiment 2, in order to verify which angle should be set within the range of 15° or more and 25° or less when actually measuring with this optical system, the change in the peak height of the scattered light intensity with respect to the angle was measured. bottom.
Experimental conditions were as follows: In the apparatus configuration shown in FIG. An optical system with a distance between centers E of 4 cm (angle γ=60°) was constructed.
In this configuration, the tilt angle θ of the analysis plane W1 of the sample W with respect to the incident light was changed, and the peak heights at the analysis points (analysis point 1 and analysis point 2) were measured.

A Si wafer was used as the sample W (the size of the sample W was the same as in Experiment 1).
In addition, iRHR320 manufactured by HORIBA, Ltd. was used as an apparatus. A diode-pumped solid-state laser (DPSS) was used as a laser device, and laser light with a wavelength of 532 nm, an output of 400 mW, and a diameter of 100 μm was used as incident light. Also, the integration time per time was set to 30 seconds, and the number of times of integration was set to eight.

The peak height (cps/s) of the scattered light intensity was measured for each of the tilt angles θ of 5°, 10°, 15°, 20°, 25°, 30°, 35° and 40°.
In addition, the measurement area on the analysis surface was measured with a diameter of 100 μm and a diameter of 3 mm when the angle to the incident light is 0°.
The graph in FIG. 8 shows the results of Experiment 3. The vertical axis of the graphs of FIGS. 8A and 8B is the scattered light peak height (cps/s), and the horizontal axis is the tilt angle (°) of the analysis plane with respect to the incident light.
As shown in the graph of FIG. 8, the peak height rises up to an inclination angle of 25° of the analysis plane, and the peak height at an inclination angle of 25° is the maximum within the range of 15° or more and 25° or less. It was confirmed.

Therefore, as the tilt angle of the analysis plane increases, the area of the measurement area on the analysis plane (the area on the sample where scattered light can pass through the aperture) becomes larger (there is a possibility that information that is not originally required can be obtained). Therefore, the amount of increase in area in the range of 15° or more and 25° or less was specifically calculated.
The graph in FIG. 9 shows the calculation results. In the graph of FIG. 9, the vertical axis is the increase in area (%) when the angle with the incident light is 0°, and the horizontal axis is the inclination angle (°) of the analysis plane with respect to the incident light. .

As shown in the graph of FIG. 9, the increase in area is about 0.2% at an angle of 15° and about 0.6% at an angle of 25°, and there is a slight increase in the range of angles from 15° to 25°. are doing.
Therefore, in the range of the angle of 15° or more and 25° or less, if it is desired to reduce the influence of the increase in the area even a little, it is preferable that the inclination angle is smaller. , to further improve the sensitivity), it was confirmed that it is necessary to reduce the diameter of the stop 14 in the configuration shown in FIG.

Claims (5)

An analysis surface formed on a flat surface of an opaque sample is irradiated with laser light as incident light, and scattered light generated from the sample is directed at 90° to the optical axis of the incident light. A laser Raman spectroscopic analysis method in which analysis is performed by passing through a condenser lens whose main surface is arranged parallel to
The angle of inclination of the analysis surface of the sample with respect to the incident light,
a line connecting the center of the principal surface of the condenser lens and the edge of the principal surface of the condenser lens;
Laser Raman spectroscopy, characterized in that the angle formed by the intersection of the analysis surface of the sample and the optical axis of the incident light and the line connecting the end of the main surface of the condenser lens is less than 1/2. analytical method. 2. A laser Raman spectroscopic analysis method according to claim 1, wherein the angle of inclination of the analysis plane of said sample with respect to said incident light is 15[deg.] or more. 3. The laser Raman spectroscopic analysis method according to claim 1, wherein a sample having a visible light transmittance of 10 ⁻⁴ % or less is used as the sample. 4. The laser Raman spectroscopic analysis method according to claim 1, wherein the incident light has a diameter of 10 [mu]m or more and 100 [mu]m or less. 5. A method of manufacturing a ceramic product, wherein the results obtained by the analysis by the laser Raman spectroscopic analysis method according to any one of claims 1 to 4 are fed back.

Images