Measurement apparatus and measurement method

Abstract

To provide a measurement apparatus and a measurement method that can block an unnecessary light component in a color confocal method while suppressing a decrease in measurement accuracy.SOLUTION: A measurement apparatus (10) includes: a light source that emits multi-wavelength light (12); a first optical unit (56) that generates chromatic aberration along an optical axis (AX) for multi-wavelength light; a second optical unit (56) that focuses the multi-wavelength light where the chromatic aberration is generated onto a measurement position of a measurement object (W); a light-reduction member (57) that blocks a part of the multi-wavelength light incident on the first optical unit and is disposed at a position through which the optical axis passes; a light reduction adjustment unit that changes an area over which the light reduction member blocks the multi-wavelength light; an aperture (AP) that transmits at least a part of the multi-wavelength light that passes through the light-reduction member; and a light reception unit that acquires spectral information of the multi-wavelength light that is passed through the aperture.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a measurement device and a measurement method. [Background technology]

[0002] Conventionally, there is known a measuring device that uses the color confocal method to measure the surface texture of a measurement target. The color confocal method is a length measurement principle that utilizes the chromatic aberration along the optical axis of a refractive optical system. In an optical system in which chromatic aberration occurs, the focal distance differs depending on the wavelength.

[0003] When measuring the surface of a measurement object, multi-wavelength light containing a plurality of mutually different wavelengths is output from the controller, and the multi-wavelength light is irradiated toward the measurement object via the optical fiber and the probe.

[0004] The multi-wavelength light emitted from the probe is focused at a different position on the optical axis for each wavelength due to chromatic aberration. The spectrometer provided in the controller detects light having a wavelength focused on the surface of the object of measurement from the reflected light of the multi-wavelength light irradiated onto the object of measurement. The wavelength of the light detected by the spectrometer is converted into a distance. In this manner, non-contact distance measurement is realized.

[0005] Patent Document 1 describes a confocal measurement device that uses a color confocal method to measure a measurement object. The confocal optical system described in the document is equipped with a light shield that blocks unnecessary light that passes through the center of a diffractive lens, thereby reducing crosstalk. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2020 / 059677 Summary of the Invention [Problem to be solved by the invention]

[0007] However, when a light-blocking object is placed on the light path as in the device described in Patent Document 1, the total amount of reflected light from the object to be measured decreases. The decrease in the total amount of reflected light can be a factor in the decrease in measurement accuracy due to the decrease in accuracy of peak detection. In particular, when a material with a relatively low reflectance is used as the object to be measured, peak detection itself becomes difficult.

[0008] The present invention has been made in consideration of the above circumstances, and aims to provide a measurement device and a measurement method that suppresses the incidence of unnecessary reflected light in color confocal method and ensures the amount of reflected light necessary for peak detection. [Means for solving the problem]

[0009] In order to achieve the above object, the following aspects of the invention are provided.

[0010] A measurement device according to a first aspect of the present disclosure includes a light source that emits multi-wavelength light including a plurality of lights having different wavelengths from each other, a first optical unit that generates chromatic aberration along an optical axis in the multi-wavelength light emitted from the light source, a second optical unit that focuses the multi-wavelength light having generated chromatic aberration to a measurement position of an object to be measured, a light-attenuating member that blocks a portion of the multi-wavelength light incident on the first optical unit and is arranged at a position through which the optical axis passes, a light-attenuation adjustment unit that varies the area ratio of the multi-wavelength light blocked by the light-attenuating member to the cross-sectional area of ​​the multi-wavelength light at the position where the light-attenuating member is arranged, an opening that transmits at least a portion of the multi-wavelength light that has passed through the light-attenuating member, and a light-receiving unit for acquiring spectral information of the multi-wavelength light that has passed through the opening.

[0011] According to the measurement device according to the first aspect of the present disclosure, the light-attenuating member blocks a portion of the multi-wavelength light incident on the first optical unit, and is disposed at a position through which the optical axis passes, and varies the area ratio of the light-attenuating member blocking the multi-wavelength light to the cross-sectional area of ​​the multi-wavelength light at the position where the light-attenuating member is disposed. This suppresses the incidence of the reflected light reflected without focusing at the measurement position of the measurement object into the light-receiving unit, and ensures the amount of reflected light required for peak detection.

[0012] A third optical unit may be provided that guides the multi-wavelength light traveling from the light source toward the first optical unit to the first optical unit. The third optical unit may include a collimator lens that can generate parallel light traveling toward the first optical unit.

[0013] An example of multi-wavelength light that has passed through a light-reducing member is multi-wavelength light that has passed through the position of the light-reducing member in the optical axis direction without being blocked by the light-reducing member.

[0014] The opening can be disposed at a position that has a conjugate relationship with the focal position of the multi-wavelength light on the measurement object.

[0015] A measurement device according to a second aspect may be the measurement device of the first aspect, wherein the light attenuation adjustment section includes a position adjustment section that adjusts the position of the light attenuation member in a direction parallel to the optical axis.

[0016] According to this aspect, the ratio of the area blocked by the light reducing member to the cross-sectional area of ​​the reflected light at the position where the light reducing member is disposed can be varied depending on the position of the light reducing member in the direction parallel to the optical axis.

[0017] The measurement device of the third aspect is the measurement device of the second aspect, and may further include a plurality of dimming members, and the position adjustment unit may further include a selection unit that selects a dimming member to be placed in a position that blocks the multi-wavelength light from among the plurality of dimming members supported at different positions in a direction parallel to the optical axis.

[0018] According to this aspect, the light reducing members can be disposed at a plurality of prescribed positions in a direction parallel to the optical axis.

[0019] A measurement device according to a fourth aspect may be the measurement device of the second aspect, wherein the position adjustment section includes a movement section that moves the light reducing member in a direction parallel to the optical axis.

[0020] According to this aspect, the light reducing member can be disposed at an arbitrary position in a direction parallel to the optical axis.

[0021] A measurement device according to a fifth aspect is the measurement device of any one of the first to fourth aspects, wherein the light reducing member is disposed between the first optical section or the second optical section and the opening.

[0022] According to this aspect, the light reducing member can be disposed on the optical path where the beam diameter of the reflected light changes.

[0023] A measurement device according to a sixth aspect is the measurement device according to any one of the first to fifth aspects, wherein the light attenuation adjustment unit includes a size variable unit that varies an area of ​​the light attenuation member that blocks the multi-wavelength light.

[0024] According to this aspect, it is possible to realize blocking of multi-wavelength light in accordance with the size of the light reducing member.

[0025] The measurement device according to the seventh aspect is a measurement device according to any one of the first to sixth aspects, and further includes a measurement condition acquisition unit that acquires measurement conditions when measuring the object to be measured, and the dimming adjustment unit may vary an area ratio of the area blocked by the dimming member to a cross-sectional area of ​​the multi-wavelength light at a position where the dimming member is placed, depending on the acquired measurement conditions.

[0026] According to this aspect, it is possible to realize preferable peak detection of reflected light according to the measurement conditions.

[0027] A measurement device according to an eighth aspect is a measurement device according to any one of the first to seventh aspects, and further comprises a probe that irradiates multi-wavelength light generating chromatic aberration onto a measurement position of an object to be measured, and into which reflected light of the multi-wavelength light irradiated onto the object to be measured is incident, and the probe may comprise a first optical unit, a second optical unit, and a dimming member.

[0028] According to this aspect, the measurement position on the measurement object is irradiated with multi-wavelength light, and the reflected light unnecessary for peak detection in the reflected light is attenuated in the probe onto which the reflected light is incident.

[0029] A measurement device according to a ninth aspect may be the measurement device of any one of the first to ninth aspects, wherein the first optical section and the second optical section are integrally configured.

[0030] The measurement method according to the present disclosure is a multi-wavelength light including a plurality of light beams having different wavelengths from each other, and is a measurement method for measuring the surface of a measurement object by irradiating the measurement object with the multi-wavelength light that generates chromatic aberration along an optical axis, the measurement method includes a light-attenuating element that focuses the multi-wavelength light that generates chromatic aberration at a measurement position of the measurement object and blocks a portion of the multi-wavelength light that enters a first optical unit that generates chromatic aberration, the light-attenuating element is placed at a position through which the optical axis passes, and an area ratio of the light-attenuating element blocking the multi-wavelength light to a cross-sectional area of ​​the multi-wavelength light at a position where the light-attenuating element is placed is varied, at least a portion of the multi-wavelength light that has passed through the light-attenuating element passes through an opening that has a conjugate relationship with the focal position of the measurement object, and spectral information of the multi-wavelength light that has passed through the opening is obtained.

[0031] According to the measurement method of the present disclosure, it is possible to obtain the same effects as those of the measurement device of the present disclosure. The components of the measurement device of the other aspects may be applied to the components of the measurement method of the other aspects. Effect of the Invention

[0032] According to the present invention, the light-reducing member blocks a part of the reflected light reflected from the object to be measured, and the light-reducing member is arranged at a position through which the optical axis passes, and varies the ratio of the area of ​​the light that the light-reducing member blocks to the cross-sectional area of ​​the reflected light at the position where the light-reducing member is arranged. This prevents the reflected light that is reflected out of focus at the measurement position of the object to be measured from entering the spectroscope, and ensures the amount of reflected light required for peak detection. [Brief description of the drawings]

[0033] [Figure 1] 1 is an overall configuration diagram showing an example of the configuration of a measurement device according to a first embodiment. [Diagram 2] FIG. 2 is a schematic diagram of an optical path of incident light. [Diagram 3] FIG. 4 is a schematic diagram of an optical path of reflected light. [Figure 4] FIG. 2 is an explanatory diagram of a color confocal method and an explanatory diagram of the occurrence of chromatic aberration. [Diagram 5] 5 is a schematic diagram showing an output signal of a spectroscope corresponding to reflected light that has passed through a peripheral portion of an objective lens. FIG. [Figure 6] FIG. 1 is an explanatory diagram of a problem with color confocal imaging, showing a schematic diagram of light passing through the center of an objective lens. [Figure 7] 4 is a schematic diagram showing an output signal of a spectroscope corresponding to reflected light that has passed through the center of a lens. FIG. [Figure 8] FIG. 13 is a schematic diagram of an output signal actually observed. [Figure 9] 2 is a schematic diagram showing a configuration example of a probe applied to the measurement device according to the first embodiment. FIG. [Figure 10] 1 is a functional block diagram showing the electrical configuration of a measurement device according to a first embodiment. FIG. [Figure 11] 4 is a flowchart showing the procedure of a measurement method according to the first embodiment. [Figure 12] 13 is a schematic diagram showing an example of the configuration of a probe applied to a measurement device according to a second embodiment. FIG. [Figure 13] FIG. 11 is a functional block diagram showing the electrical configuration of a measurement device according to a second embodiment. [Figure 14] 13A and 13B are schematic diagrams showing configuration examples of a probe according to a modified example. [Figure 15] 10A and 10B are front views of the light-reducing member, showing examples of sizes of the light-reducing member. [Figure 16] FIG. 11 is a functional block diagram showing the electrical configuration of a measurement device according to a third embodiment. [Figure 17] 13 is a flowchart showing the procedure of a measurement method according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification, the same components are given the same reference numerals and duplicated explanations will be omitted as appropriate.

[0035] [Overall configuration of the measuring device according to the first embodiment] FIG. 1 is an overall configuration diagram showing an example of the configuration of a measuring device according to a first embodiment. The measuring device 10 shown in the figure uses a color confocal method that uses the measurement principle that utilizes the axial chromatic aberration of a refractive optical system. The axial chromatic aberration is chromatic aberration that occurs in a direction along the optical axis. In an optical system in which chromatic aberration occurs, the focal distance differs for each wavelength, and the reflected light that is focused at the measurement position WP of the measurement object W mainly returns to the optical fiber F3. Using the spectrometer 20, the reflected light that is focused at the measurement position WP of the measurement object W is read, and the wavelength of the reflected light is converted into a distance. In this way, the distance between the probe 50 and the measurement position WP of the measurement object W is derived, and non-contact measurement of the measurement object W is realized.

[0036] The measurement device 10 includes a controller 11. The controller 11 includes a light source 12, a light guiding member 14, an optical connector C1, an optical fiber F1, an optical branching device C2, an optical fiber F2, an optical connector C3, an optical fiber F4, and an optical connector C5.

[0037] The light source 12 is a light source that emits multi-wavelength light L1 that includes a plurality of wavelengths different from each other. Examples of light-emitting elements applied to the light source 12 include light-emitting diodes, laser diodes, and halogen lamps. The light-emitting diodes may be referred to as LEDs, which are an abbreviation of Light-Emitting Diode. Examples of the multi-wavelength light L1 include broadband light and white light. The wavelength may include the concept of color in the above-mentioned chromatic aberration.

[0038] The light-guiding member 14 condenses the light emitted from the light source 12 toward the optical connector C1, which is the light input portion of the optical fiber F1. Although one lens is illustrated as the light-guiding member 14 in Fig. 1, the light-guiding member 14 may include a plurality of optical elements, such as a plurality of lenses.

[0039] The optical connector C1 functions as one end of the optical fiber F1. The optical fiber F1 is connected to one end of the optical fiber F2 and one end of the optical fiber F4 via the optical splitter C2. The other end of the optical fiber F2 is connected to the optical connector C3.

[0040] A merging port of the optical splitter C2 is connected to the optical fiber F2. A first port on the splitting side of the optical splitter C2 is connected to the other end of the optical fiber F1. A second port on the splitting side of the optical splitter C2 is connected to one end of the optical fiber F4. The other end of the optical fiber F4 is connected to the optical connector C5. Examples of the optical splitter C2 include an optical coupler, a splitter, and an optical circulator.

[0041] The controller 11 includes a spectrometer 20. The spectrometer 20 is connected to an optical fiber F4 via an optical connector C5. The spectrometer 20 receives reflected light L2 from the measurement object W via the probe 50, the optical fiber F3, the optical fiber F4, and the like.

[0042] The probe 50 includes a probe housing 52, a condenser lens 54, an objective lens 56, and an optical connector C4. In the probe 50, the multi-wavelength light L1 emitted from the controller 11 is input from the optical connector C4 via an optical fiber F3.

[0043] The probe housing 52 supports the condenser lens 54 and the objective lens 56 therein. The structure supporting the condenser lens 54 and the objective lens 56 is not shown. An optical connector C4 is attached to the end of the probe housing 52 opposite to the end supporting the objective lens 56. A light-reducing member 57 that blocks a portion of the multi-wavelength light L1 entering the condenser lens 54 is disposed on the optical connector C4 side of the condenser lens 54. The light-reducing member 57 will be described in detail later.

[0044] FIG. 2 is a schematic diagram of the optical path of incident light. FIG. 3 is a schematic diagram of the optical path of reflected light. FIG. 3 illustrates the distribution of light intensity of reflected light L2 condensed to an aperture AP. The condensing lens 54 causes the multi-wavelength light L1 to be incident on the objective lens 56, and causes the reflected light L2 returning from the measurement object W to be incident again to the aperture AP. The condensing lens 54 may have a function of changing the beam size of the multi-wavelength light L1, or may have a collimating function. The condensing lens 54 in this embodiment functions as an achromatic lens and also functions as a collimator lens.

[0045] The objective lens 56 generates chromatic aberration in the multi-wavelength light L1 along the optical axis AX of the multi-wavelength light L1, and focuses the multi-wavelength light L1 with the chromatic aberration on the measurement position of the measurement object W. That is, the probe 50 irradiates the measurement position of the measurement object W with a spot light of the multi-wavelength light L1. The function of generating chromatic aberration can be achieved by using known members such as a refractive lens, a diffractive lens, and a lens in which chromatic aberration is intentionally left. In Figs. 1 to 3, one lens having a function of generating chromatic aberration and a function of focusing is illustrated as the objective lens 56, but the objective lens 56 may be configured as a lens group including a plurality of lenses corresponding to each of a plurality of functions. For example, the objective lens 56 may include a first lens that generates chromatic aberration along the optical axis of the multi-wavelength light L1, and a second lens that focuses the multi-wavelength light L1 on the measurement object W. The objective lens 56 described in the embodiment is an example of a first optical unit and an example of a second optical unit.

[0046] 1, the reflected light L2 returning from the measurement object W is input to the controller 11 via the aperture AP, the optical connector C4, the optical fiber F3, and the optical connector C3. The reflected light L2 input to the controller 11 is input to the spectrometer 20 via the optical fiber F2, the optical branching device C2, the optical fiber F4, and the optical connector C5.

[0047] The spectrometer 20 includes a spectroscopic element 22 and a photodetector 24. The spectroscopic element 22 separates the reflected light L2 input to the spectrometer 20 into single-component light for each wavelength. The single-component light for each wavelength may be referred to as monochromatic light. Although a reflective diffraction grating is illustrated as an example of the spectroscopic element 22 in FIG. 1, the spectroscopic element 22 may be a transmissive diffraction grating or a prism. The spectroscopic element 22 described in the embodiment is an example of a light receiving unit that acquires spectral information of the multi-wavelength light that has passed through an opening.

[0048] The photodetector 24 detects the wavelength at which the light intensity is maximum. In other words, the photodetector 24 is an optical element that detects the reflected light L2 dispersed into monochromatic light. Examples of the photodetector 24 include a CCD image sensor and a CMOS image sensor. CCD is an abbreviation for Charge Coupled Device. CMOS is an abbreviation for Complementary Metal Oxide Semiconductor. The wavelength of the light incident on the photodetector 24 shown in FIG. 1 becomes shorter toward the lower left and longer toward the upper right in FIG. 1.

[0049] The probe 50 includes a light-attenuating member 57. The light-attenuating member 57 is disposed on the optical path of the multi-wavelength light L1, which is incident light. The light-attenuating member 57 is a light-attenuating member that blocks a portion of the multi-wavelength light L1 that is incident on the probe 50 via the optical connector C4 and then on the condenser lens 54. Although not shown in the figure, the light-attenuating member 57 is supported using a support structure.

[0050] 1 is a line sensor in which pixels are arranged one-dimensionally along the irradiation direction of light dispersed by the dispersing element 22. The monochromatic light dispersed by the dispersing element 22 is reflected at angles different from each other for each wavelength and input to each pixel of the photodetector 24.

[0051] Instead of a line sensor, an area sensor in which multiple pixels are arranged two-dimensionally may be applied to the photodetector 24. When the light intensity of each monochromatic light is obtained in the area sensor, pixel values ​​of pixels arranged in a direction perpendicular to the direction in which the reflected light L2 is dispersed may be added.

[0052] The graph shown in Fig. 1 is an example of an output signal from the photodetector 24. The horizontal axis of the graph shown in Fig. 1 is the wavelength of the reflected light L2, and the vertical axis is the light intensity, and the graph shown in Fig. 1 represents the light intensity for each wavelength of the reflected light L2. The horizontal axis is understood as the pixel position of the line sensor. The light intensity is understood as the pixel value for each pixel of the line sensor.

[0053] 1, the pixel with the maximum light intensity is identified, and the wavelength of the reflected light L2 corresponding to the identified pixel is identified. The wavelength with the maximum light intensity is converted into a distance and calculated as the distance from the probe 50 to the measurement position of the object W. If the distance from the probe 50 to the reference position of the object W is known, the displacement from the reference position to the measurement position on the object W can be calculated. In this way, high-precision measurement of the object W is achieved in non-contact measurement.

[0054] [Detailed explanation of color confocal method] 4 is an explanatory diagram of the color confocal method and the occurrence of chromatic aberration. Of the multi-wavelength light L1, the multi-wavelength light L10 that passes through the peripheral portion 56A of the objective lens 56 generates relatively large chromatic aberration, and the focal position on the optical axis AX differs for each wavelength. Here, the peripheral portion 56A of the objective lens 56 is an area on the light-entering or light-exiting surface of the objective lens 56 that does not include the position of the optical axis AX of the objective lens 56. The optical axis AX of the objective lens 56 coincides with the optical axis AX of the multi-wavelength light L1.

[0055] For example, on the surface of objective lens 56 where light enters or exits, the area toward the edge of objective lens 56, centered on the position of the optical axis AX, and having a diameter that is 20 percent of the diameter of objective lens 56, can be defined as peripheral portion 56A of objective lens 56.

[0056] Furthermore, on the light-entering or light-emitting surface of the objective lens 56, a region having a diameter of 20 percent of the diameter of the objective lens 56, centered on the position of the optical axis AX, can be defined as the central portion 56B of the objective lens 56. In the probe 50 shown in FIG. 1, the reflected light L2 from the measurement target W becomes parallel light between the objective lens 56 and the condenser lens 54, so the definition of the peripheral portion 56A of the objective lens 56 can be adopted as the definition of the peripheral portion of the condenser lens 54. Similarly, the definition of the central portion 56B of the objective lens 56 can be adopted as the definition of the central portion of the condenser lens 54. In other words, on the light-entering or light-emitting surface of the condenser lens 54, a region on the edge side of the condenser lens 54 than a region having a diameter of 20 percent of the diameter of the condenser lens 54, centered on the position of the optical axis AX, can be defined as the peripheral portion of the condenser lens 54. Furthermore, an area having a diameter of 20 percent of the diameter of the focusing lens 54, centered on the position of the optical axis AX, on the light incident or exit surface of the focusing lens 54, can be defined as the center of the focusing lens 54.

[0057] 4 illustrates incident light L11 that is focused on the surface WS of the measurement object W, and incident light L12 and incident light L13 that are not focused on the surface WS of the measurement object W. The surface WS of the measurement object W here is the surface of the measurement object W that faces the exit surface of the probe 50.

[0058] Fig. 4 illustrates a focal position FP1 on the optical axis AX of the incident light L11, a focal position FP2 on the optical axis AX of the incident light L12, and a focal position FP3 on the optical axis AX of the incident light L13. Fig. 4 illustrates reflected light L21 that passes through the peripheral portion 56A of the objective lens 56, out of the reflected light L2 reflected at the focal position FP1, and does not illustrate reflected light L2 that passes through the central portion of the objective lens 56, etc.

[0059] Of the reflected light L2, reflected light L21 reflected at the focal position FP1 on the surface WS of the measurement target W is focused at the aperture AP of the optical fiber F4 shown in Fig. 1. Then, most of the reflected light L21 is guided to the optical fiber F4.

[0060] In other words, the focal position FP1 on the surface WS of the object to be measured W and the position of the aperture AP of the optical fiber F4 are in an optically conjugate relationship. The aperture AP of the optical fiber F4 functions as a spatial filter or pinhole that selectively passes reflected light corresponding to the incident light focused on the surface WS of the object to be measured W.

[0061] On the other hand, the reflected light L2 that is not focused on the surface WS of the measurement object W is not focused at the aperture AP of the optical fiber F4. That is, the reflected light L2 that is not focused on the surface WS of the measurement object W is diffused in the vicinity of the aperture AP of the optical fiber F4. As a result, the reflected light L2 that is not focused on the surface WS of the measurement object W has a lower light guide efficiency when passing through the optical fiber F4 compared to the reflected light L21 that is focused on the surface WS of the measurement object W.

[0062] Therefore, of the reflected light L2, the reflected light L21 corresponding to the incident light L11 focused at the focusing position FP1 on the surface WS of the measurement object W has a higher light intensity than the reflected light L2 corresponding to the incident light L12 that is not focused at the focusing position FP1 on the surface WS of the measurement object W. The reflected light L21 described in the embodiment is an example of a first reflected light. The reflected light L2 that is not focused on the surface WS of the measurement object W described in the embodiment is an example of a second reflected light. The opening AP described in the embodiment is an example of an opening that passes at least a part of the multi-wavelength light that has passed through the light-reducing member.

[0063] Fig. 5 is a schematic diagram showing an output signal of a spectroscope corresponding to reflected light that has passed through the periphery of the objective lens. Fig. 5 illustrates the output signal of the spectroscope 20 shown in Fig. 1 in a graph format. The horizontal axis of the graph shown in Fig. 5 is wavelength, and the vertical axis is light intensity. The horizontal axis of the graph in Fig. 5 indicates longer wavelengths toward the left and shorter wavelengths toward the right. The same applies to the graphs shown in Figs. 3, 7 and 8.

[0064] 5 represents the wavelength of the reflected light L21. The wavelengths λ12 and λ13 represent the wavelengths of the reflected light L2 corresponding to the incident light L12 and the reflected light L2 corresponding to the incident light L13, respectively. The reflected light L21 having the wavelength λ11 has a maximum output signal value representing the light intensity.

[0065] 6 is an explanatory diagram of the problem of the color confocal method, and is a schematic diagram of light passing through the center of the objective lens. Of the multi-wavelength light L14 incident on the center 56B of the objective lens 56, the incident light L15 is focused at a focal position FP11 on the surface WS of the measurement object W. On the other hand, of the multi-wavelength light L14, the incident light L16 and the incident light L17 are focused at focal positions FP12 and FP13, respectively, which are not on the surface WS of the measurement object W.

[0066] The multi-wavelength light L14 incident on the central portion 56B of the objective lens 56 generates chromatic aberration, but the generated chromatic aberration is smaller than that generated by the multi-wavelength light L10, etc., incident on the peripheral portion 56A of the objective lens 56 shown in FIG.

[0067] In theory, no chromatic aberration occurs at the center 56C of the objective lens 56 through which the optical axis AX of the incident light L15 etc. passes. That is, all wavelengths of the reflected light L2 passing through the center 56C of the objective lens 56 are guided to the spectroscope 20 regardless of the position of the measurement target W. The symbol L22 denotes the reflected light of the multi-wavelength light L14 incident on the central portion 56B of the objective lens 56.

[0068] Fig. 7 is a schematic diagram showing the output signal of the spectrometer corresponding to the reflected light that has passed through the center of the lens. Fig. 7 illustrates the output signal of the spectrometer 20 shown in Fig. 1 in a graph format. The horizontal axis of the graph shown in Fig. 7 is wavelength, and the vertical axis is light intensity. The curve showing light intensity shown in Fig. 7 has a wider wavelength band corresponding to the peak compared to the curve showing light intensity shown in Fig. 5.

[0069] 8 is a schematic diagram of an output signal actually observed. The signal SO actually output from the spectrometer 20 is obtained by superimposing the spectrometer output signal SOC corresponding to the reflected light that has passed through the central part 56B of the objective lens 56 on the spectrometer output signal SOP corresponding to the reflected light that has passed through the peripheral part 56A of the objective lens 56.

[0070] That is, the signal SO actually output from the spectrometer 20 has a wider wavelength band of peak light intensity than the output signal SOP of the spectrometer corresponding to the reflected light that has passed through the peripheral portion 56A of the objective lens 56. The relative broadening of the wavelength band of peak light intensity affects the accuracy of detecting the peak light intensity when calculating the wavelength of the reflected light L2, and can be a factor in reducing the measurement resolution.

[0071] Therefore, the measuring device 10 according to the embodiment includes a light-reducing member 57 in the probe 50, and the light-reducing member 57 is adjusted. At least a part of the multi-wavelength light L1 that passes through the center of the condenser lens 54 shown in FIG. 1 and the like among the multi-wavelength light L1 inputted to the probe 50 is attenuated, and as a result, the multi-wavelength light L14 that passes through the center 56B of the objective lens 56 shown in FIG. 6 is attenuated. At least a part of the multi-wavelength light L1 that passes through the center 56B of the objective lens 56 does not reach the measurement position of the measurement target W, and at least a part of the reflected light L22 that passes through the center 56B of the objective lens 56 shown in FIG. 6 is attenuated, and at least a part of the reflected light L22 that passes through the center of the condenser lens 54 is attenuated. As a result, in the measuring device 10 according to the embodiment, the amount of unnecessary light among the reflected light L2 guided to the spectroscope 20 is suppressed, and a decrease in the amount of necessary light is suppressed, and a specified measurement accuracy is ensured due to the assurance of detection accuracy of a specified light intensity.

[0072] [Example of the configuration of the probe applied to the measurement device according to the first embodiment] Fig. 9 is a schematic diagram showing a configuration example of a probe applied to the measurement device according to the first embodiment. The probe 50 shown in the figure is configured so that a light-attenuating member 57 can be freely placed at any position on the optical path where the beam diameter of the multi-wavelength light L1 changes. Fig. 9 also shows a schematic diagram of a selector 100 that supports the light-attenuating member 57 and selectively changes the position of the light-attenuating member 57.

[0073] The selector 100 includes a support member 101 that supports the multiple attenuation members 57, and a selection member that selectively positions each of the multiple attenuation members 57 at different attenuation positions P1, P2, and P3 in a direction parallel to the optical axis AX. Fig. 9 illustrates a probe 50 that includes three attenuation members 57, one of which is positioned on the optical path of the multi-wavelength light L1.

[0074] This makes it possible to obtain the same effect as changing the size of the light-reducing member 57 disposed on the optical path of the multi-wavelength light L1. For example, when the light-reducing member 57 is disposed at the light-reducing position P1, the ratio of the area covered by the light-reducing member 57 to the cross-sectional area of ​​the multi-wavelength light L1 at the position where the light-reducing member 57 is disposed becomes smaller than when the light-reducing member 57 is disposed at the light-reducing positions P2 and P3, and as a result, the amount of reflected light L2 reaching the aperture AP of the optical fiber F4 increases relatively. Note that the cross-sectional area of ​​the multi-wavelength light L1 represents the cross-sectional area of ​​the multi-wavelength light L1 in a plane perpendicular to the optical axis of the multi-wavelength light L1.

[0075] Similarly, when the light-reducing member 57 is disposed at the light-reducing position P2, the ratio of the area covered by the light-reducing member 57 to the cross-sectional area of ​​the multi-wavelength light L1 at the position where the light-reducing member 57 is disposed is smaller than when the light-reducing member 57 is disposed at the light-reducing position P3, and as a result, the amount of reflected light L2 reaching the aperture AP of the optical fiber F4 is relatively increased. That is, when the light-reducing member 57 is disposed at a position relatively close to the condenser lens 54, the amount of reflected light L2 reaching the aperture AP of the optical fiber F4 is relatively increased. On the other hand, when the light-reducing member 57 is disposed at a position relatively far from the condenser lens 54, the amount of reflected light L2 reaching the aperture AP of the optical fiber F4 is relatively decreased. On the other hand, when the light-reducing member 57 is disposed at any of the light-reducing positions P1, P2, and P3, the reflected light L2 passing through the center portion 54B of the condenser lens 54 is prevented from reaching the aperture AP of the optical fiber F4.

[0076] FIG. 9 illustrates an example of a selector 100 for inserting the light-attenuating member 57 supported outside the probe 50 into the probe 50 , but the selector 100 may be provided inside the probe 50 .

[0077] The selector 100 described in the embodiment is an example of a component of a light attenuation adjustment unit that varies the area ratio where the light attenuation member blocks the multi-wavelength light to the cross-sectional area of ​​the multi-wavelength light at the position where the light attenuation member is placed, and is an example of a component of a position adjustment unit that adjusts the position of the light attenuation member in a direction parallel to the optical axis. Also, the selector 100 described in the embodiment is an example of a component of a selection unit that selects the light attenuation member to be placed at a position where it blocks the multi-wavelength light.

[0078] [Example of electrical configuration of the measuring device according to the first embodiment] 10 is a functional block diagram showing the electrical configuration of the measurement device according to the first embodiment. A computer is applied to the control unit 120 of the measurement device 10. The computer may be a personal computer, a workstation, or a tablet terminal. The computer may be a virtual machine.

[0079] The control unit 120 includes one or more non-transitory tangible computer-readable media 122. The computer-readable media 122 includes a memory 124 that functions as a primary storage device and a storage 126 that functions as a secondary storage device.

[0080] The computer-readable medium 122 may be a semiconductor memory, a hard disk drive, a solid-state drive, etc. The computer-readable medium 122 may be any combination of multiple devices.

[0081] A hard disk device may be referred to as an HDD, which is an abbreviation of the English term Hard Disk Drive, and a solid state drive device may be referred to as an SSD, which is an abbreviation of the English term Solid State Drive.

[0082] The memory 124 of the computer readable medium 122 stores a program 130, measurement data 132, and dimming position data 134. The computer readable medium 122 may comprise a device on which the program 130 is stored, a device on which the measurement data 132 is stored, and a device on which the dimming position data 134 is stored.

[0083] The program 130 includes various programs for realizing various functions of the measurement device 10. The measurement data 132 includes measurement data of the measurement object W acquired when the measurement of the measurement object W shown in FIG. 1 is performed. The measurement data may include coordinate values ​​of each measurement position on the measurement object W. The light attenuation position data 134 includes the position of the light attenuation member 57 in the direction along the optical axis AX. The position of the light attenuation member 57 in the direction along the optical axis AX is stored in association with the measurement conditions.

[0084] The control unit 120 includes a light source control unit 140. The light source control unit 140 executes a light source control program to realize an operation control function of the light source 12. The operation control of the light source 12 includes an on / off control of the light source 12 and a control of the amount of light emitted by the light source 12.

[0085] The control unit 120 includes a light detection signal processing unit 142. The light detection signal processing unit 142 executes a light detection signal processing program to realize a light detection signal processing function. The light detection signal processing derives a peak wavelength at which the light intensity is maximum from the light detection signal acquired from the spectrometer 20, and derives a measurement value for each measurement position of the measurement object W based on the peak wavelength. The light detection signal processing unit 142 associates the measurement value for each measurement position of the measurement object W with the measurement position and stores it in the memory 124 as measurement data 132. Note that the light detection signal processing unit 142 described in the embodiment is an example of a signal processing unit that derives a measurement result of the measurement position of the measurement object based on the detection result of the spectrometer.

[0086] The control unit 120 includes a probe drive control unit 144. The probe drive control unit 144 executes a probe drive program to realize an operation control function of the probe drive unit 160. The probe drive unit 160 includes a support member that supports the probe 50 and a relative movement member that moves the probe 50 and the measurement object W relatively to each other.

[0087] The probe driving unit 160 may move the probe 50 relative to the fixed object to be measured W, or may move the object to be measured W relative to the fixed probe 50. Furthermore, the probe driving unit 160 may move both the object to be measured W and the probe 50.

[0088] The control unit 120 includes a measurement condition acquisition unit 146. The measurement condition acquisition unit 146 includes measurement conditions such as the type of the measurement object W. Examples of the measurement conditions may include the name of the measurement object W, the material of the measurement object W, the color of the measurement object W, the reflectance of the measurement object W, and the type of surface treatment of the measurement object W.

[0089] The control unit 120 includes a selector control unit 148. The selector control unit 148 controls the operation of the selector 100. That is, the selector control unit 148 sets the position of the light-attenuating member 57 by referring to the light-attenuating position data 134 using the measurement conditions of the measurement target W as parameters. The selector control unit 148 operates the selector 100 to select the light-attenuating member 57 corresponding to the set position of the light-attenuating member 57, and disposes the selected light-attenuating member 57 at a specified position. The selector control unit 148 is an example of a component of the light-attenuation adjustment unit and an example of a component of the selection unit.

[0090] The control unit 120 includes an input / output interface 150. The input / output interface 150 realizes data communication with an external device. The input / output interface 150 may apply wireless communication or wired communication. The input / output interface 150 may be provided with a plurality of types of ports corresponding to a plurality of different standards. An example of a standard applied to the input / output interface 150 is USB (registered trademark). Note that USB is an abbreviation for Universal Serial Bus.

[0091] The input signal acquiring unit 152 acquires an input signal transmitted from the input device 162. The input device 162 includes a keyboard, a mouse, and the like. The input signal acquiring unit 152 acquires information input by an operator operating the input device 162 as an input signal. The control unit 120 transmits a command signal based on the input information acquired using the input signal acquiring unit 152 to various control units.

[0092] The control unit 120 includes a display control unit 154. The display control unit 154 transmits a display control signal to a display 164, and causes the display 164 to display various information. The display 164 may be a touch panel type display that is integrated with an input device 162.

[0093] One or more processors are applied to various processing units provided in the control unit 120. The processor may be a CPU or a dedicated device. Note that CPU is an abbreviation for Central Processing Unit. One processing unit may be configured using one processor, or may be configured using multiple processors. Multiple processing units may be configured using one processor. The multiple processors may be devices of the same type, or devices of different types may be used.

[0094] [Procedure of the measurement method according to the first embodiment] Fig. 11 is a flow chart showing the procedure of the measurement method according to the first embodiment. In a measurement start command acquisition step S10, the control unit 120 shown in Fig. 10 acquires a measurement start command signal indicating the start of measurement of the measurement object W. When the control unit 120 acquires the measurement start command signal, it starts measuring the measurement object W shown in Fig. 1. After the measurement start command acquisition step S10, the process proceeds to a measurement condition acquisition step S12.

[0095] In the measurement condition acquisition step S12, the measurement condition acquisition unit 146 acquires measurement conditions such as the type of the measurement object W. The measurement conditions may be acquired from design information of the measurement object W, or may be acquired from information input by the operator using the input device 162. After the measurement condition acquisition step S12, the process proceeds to a dimming position setting step S14.

[0096] In the light attenuation position setting step S14, the selector control unit 148 determines the position of the light attenuating member 57 in the probe 50 based on the measurement conditions acquired in the measurement condition acquisition step S12, and places the light attenuating member 57. After the light attenuation position setting step S14, the process proceeds to a tentative measurement step S16.

[0097] In the tentative measurement step S16, the control unit 120 irradiates the multi-wavelength light L1 from the probe 50 to a predefined tentative measurement position on the measurement target W, and determines whether or not it is possible to detect a peak of the reflected light L2. If the control unit 120 determines that it is difficult to detect a peak of the reflected light L2 in the tentative measurement step S16, the determination is No. If the determination is No, the process proceeds to the light attenuation position change step S18.

[0098] In the dimming position changing step S18, the selector control unit 148 changes the position of the dimming member 57 set in the dimming position setting step S14. After the dimming position changing step S18, the process proceeds to the tentative measurement step S16, and the tentative measurement step S16 and the dimming position changing step S18 are repeatedly executed until the tentative measurement step S16 is judged as Yes. If the control unit 120 judges in the tentative measurement step S16 that it is difficult to detect a peak at all positions of the dimming member 57, an error indicating this may be notified. The error may be notified by displaying an error message on the display 164, or by using a sound such as a voice or an alarm sound.

[0099] On the other hand, if the control unit 120 determines that peak detection is possible in the provisional measurement step S16, the determination is Yes. If the determination is Yes, the process proceeds to the main measurement step S20.

[0100] In the main measurement step S20, the control unit 120 executes a main measurement of the measurement object W. In the main measurement, the measurement position defined on the measurement object W is aligned with the irradiation position of the multi-wavelength light L1 irradiated from the probe 50, the reflected light L2 from the measurement object W is acquired, and the measurement value for each measurement position is derived and acquired based on the peak detection result of the reflected light L2 for each measurement position. The acquired measurement value is stored in the memory 124 as measurement data 132 for each measurement position.

[0101] During the execution of the main measurement step S20, a main measurement completion determination step S22 is executed. In the main measurement completion determination step S22, the control unit 120 determines whether or not the measurement of the measurement object W has been completed. If it is determined in the main measurement completion determination step S22 that the measurement of the measurement object W should be continued, a No determination is made. If a No determination is made, the main measurement completion determination step S22 continues.

[0102] On the other hand, if it is determined in the measurement end determination step S22 that the measurement of the measurement object W is to be ended, a Yes determination is made. If the determination is Yes, the process proceeds to an end processing step S24, where a specified end processing is executed and the procedure of the measurement method is ended. Examples of the end of the measurement of the measurement object W include a case where measurement values ​​are obtained for all of the specified measurement positions, and a case where the measurement of the measurement object W is forcibly ended.

[0103] [Effects of the first embodiment] The measuring device 10 and the measuring method according to the first embodiment can provide the following advantageous effects.

[0104] [1] The probe 50 provided in the measurement device 10 includes a light-reducing member 57 disposed between the condenser lens 54 and the aperture AP of the optical fiber F4, which reduces the intensity of the multi-wavelength light L1 passing through the central portion 54B of the condenser lens 54. The position of the light-reducing member 57 in the direction along the optical axis AX is determined according to the measurement conditions of the measurement object W, including the type of the measurement object W. This prevents unwanted reflected light L2, which is reflected light of the multi-wavelength light L1 passing through the central portion 56B of the objective lens 56, from being incident on the spectroscope 20, and ensures the amount of reflected light L2 required for peak detection, thereby preventing a decrease in the accuracy of peak detection.

[0105] [2] The measuring device 10 includes a selector 100 that sets one of a plurality of dimming positions P1, etc. in a direction along the optical axis AX in accordance with the measurement conditions of the measurement object W, and disposes the dimming member 57 at the set dimming position P1, etc. This realizes automatic disposition of the dimming member 57 in accordance with the measurement conditions of the measurement object W.

[0106] [3] In the measurement device 10, when the amount of reflected light L2 reaching the aperture AP of the optical fiber F4 is to be relatively increased, the light attenuating member 57 is moved relatively closer to the condenser lens 54. On the other hand, in the measurement device 10, when the amount of reflected light L2 reaching the aperture AP of the optical fiber F4 is to be relatively decreased, the light attenuating member 57 is moved relatively farther away from the condenser lens 54. This makes it possible to adjust the amount of reflected light L2 input to the aperture AP of the optical fiber F4.

[0107] [4] In the measuring device 10, a provisional measurement is performed before a main measurement of the measurement object W is performed, and a light-attenuating position of the light-attenuating member 57 at which a preferable peak of the reflected light L2 is detected is specified. This allows for highly accurate measurement according to the measurement conditions of the measurement object W.

[0108] [Example of the configuration of the probe applied to the measurement device according to the second embodiment] Fig. 12 is a schematic diagram showing a configuration example of a probe applied to a measurement device according to the second embodiment. In a probe 250 shown in the figure, the position of a light-attenuating member 57 is determined using a moving mechanism 210 shown in Fig. 12 instead of the selector 100 shown in Fig. 9. That is, the moving mechanism 210 includes a guide 212 extending in a direction parallel to the optical axis AX, a carriage 214 moving along the guide 212, and a light-attenuating support member 216 supporting the light-attenuating member 57 with respect to the carriage 214.

[0109] The moving mechanism 210 moves the light-reducing member 57 in a direction parallel to the optical axis AX, and disposes the light-reducing member 57 at a specified light-reducing position. A linear moving mechanism such as a ball screw and a linear slider is applied to the moving mechanism 210. The moving mechanism 210 described in the embodiment is an example of a moving unit that moves the light-reducing member in a direction parallel to the optical axis.

[0110] [Example of electrical configuration of the measuring device according to the second embodiment] Fig. 13 is a functional block diagram showing the electrical configuration of a measuring device according to the second embodiment. The measuring device 200 shown in the figure includes a control unit 220 instead of the control unit 120 shown in Fig. 10. The control unit 220 shown in Fig. 13 includes a movement mechanism control unit 248 instead of the selector control unit 148 shown in Fig. 10.

[0111] The moving mechanism control unit 248 controls the operation of the moving mechanism 210 in accordance with the measurement conditions of the measurement object W. That is, the moving mechanism control unit 248 sets the position of the light attenuating member 57 defined in accordance with the measurement conditions of the measurement object W, and operates the moving mechanism 210 to move the light attenuating member 57 to the defined light attenuation position. The movement resolution of the moving mechanism 210 can be defined in accordance with the accuracy of peak detection of the reflected light L2.

[0112] The movement mechanism control unit 248 can improve the S / N ratio in peak detection by disposing the light-attenuating member 57 at a position where the light-attenuation of the reflected light L2 is maximized within a range where the peak of the reflected light L2 can be detected. For example, the movement mechanism control unit 248 disposes the light-attenuating member 57 at a position where the reflected light L2 exceeds 50 percent of the maximum value of the dynamic range of the photodetector 24.

[0113] [Procedure of the measurement method according to the second embodiment] The measurement method according to the second embodiment may apply the procedure of the flowchart shown in Fig. 11. In the measurement method according to the second embodiment, in the main measurement step S20, peak detection may be performed while changing the position of the light-reducing member 57. In other words, without performing a provisional measurement, the optimal position of the light-reducing member 57 may be set in the main measurement, and measurement may be performed for each measurement position.

[0114] [Effects of the second embodiment] The measuring device 200 and the measuring method according to the second embodiment can provide the following advantageous effects.

[0115] [1] The measuring device 200 includes a moving mechanism 210 that moves the light reducing member 57 between the condenser lens 54 and the aperture AP of the optical fiber F4 along a direction parallel to the optical axis AX. The measuring device 200 includes a moving mechanism control unit 248 that controls the operation of the moving mechanism 210 in accordance with the measurement conditions of the measurement object W. This makes it possible to obtain the same effects as those of the first embodiment.

[0116] [2] The measuring device 200 can provide greater freedom in arranging the light reducing member 57 than the measuring device 10 shown in FIG.

[0117] [3] The measuring device 200 can detect the peak of the reflected light L2 by changing the light attenuation position where the light attenuating member 57 is disposed in the measurement of the measurement object W. This allows the light attenuating member 57 to be adjusted to an optimal light attenuation position for each measurement position of the measurement object W.

[0118] [Modification of the arrangement of the light-reducing member] Fig. 14 is a schematic diagram showing a configuration example of a probe according to a modified example. Fig. 1 and other figures show an example of the measurement device 10 in which the light-reducing member 57 is disposed between the condenser lens 54 and the aperture AP of the optical fiber F4, but the arrangement of the light-reducing member 57 is not limited thereto.

[0119] 14, the light-reducing member 57A may be disposed between the objective lens 56 and the condenser lens 54 in the probe 50A. Also, the light-reducing member 57B may be disposed between the measurement target W and the objective lens 56 in the probe 50A. That is, the position of the light-reducing member 57 is not limited as long as it can block the multi-wavelength light L1 passing through the central portion 56B of the objective lens 56 and change the beam diameter of the multi-wavelength light L1 passing through the condenser lens 54.

[0120] [Example of the configuration of light-reducing components] 15 is a front view of a light-reducing member showing an example of the size of the light-reducing member. The figure shows a schematic diagram of the arrangement and size of the light-reducing member 57 relative to the condenser lens 54. The direction perpendicular to the figure is the direction of the optical axis AX of the condenser lens 54.

[0121] 15 illustrates a light-reducing member 57 having a diameter D2 that is 20 percent of the diameter D1 of the condenser lens 54, and having the same circular shape as the planar shape of the condenser lens 54. Also illustrated in the same figure is the light-reducing member 57 disposed at a position where the optical axis AX of the multi-wavelength light L1 passes through the center O.

[0122] The diameter D2 of the light-attenuating member 57 may be less than 20 percent of the diameter D1 of the condensing lens 54. The minimum value of the diameter D2 of the light-attenuating member 57 may be specified in terms of the strength of the light-attenuating member 57 and the handling of the light-attenuating member 57. For example, the diameter D2 of the light-attenuating member 57 may be adjusted in a range of 5 percent or more and less than 20 percent of the diameter D1 of the condensing lens 54.

[0123] The material of the dimming member 57 is not limited as long as it can dim the multi-wavelength light L1. For example, the dimming member 57 may be made of a material such as resin or metal. The color of the dimming member 57 is not limited as long as it can dim the reflected light L2. For example, the dimming member 57 may be made of a color such as black.

[0124] The planar shape of the light-reducing member 57 is not limited to a circle. The planar shape of the light-reducing member 57 may be various shapes such as an ellipse, a rectangle, or a shape that combines a semicircle and a rectangle. The thickness of the light-reducing member 57 is not particularly limited as long as it can reduce the reflected light L2. The thickness of the light-reducing member 57 may be determined according to the overall length in the direction along the optical axis AX in the region where the light-reducing member 57 is arranged.

[0125] [Configuration example of the measurement device according to the third embodiment] Fig. 16 is a functional block diagram showing the electrical configuration of a measurement device according to the third embodiment. A measurement device 300 according to the third embodiment includes a light reduction size changing unit 310 instead of the selector 100 provided in the measurement device 10 shown in Fig. 10. The light reduction size changing unit 310 selectively switches the size of the light reduction member 57 depending on the measurement conditions of the measurement target W.

[0126] For example, the dimming size changing unit 310 may select only one dimming member 57 having a size specified according to the measurement conditions of the object to be measured W from among a plurality of dimming members 57 having different sizes, and may apply a mode in which the selected dimming member 57 is placed at a specified dimming position.

[0127] Furthermore, the measuring device 300 includes a control unit 320 instead of the control unit 120 shown in Fig. 10. The control unit 320 includes a light reduction size change control unit 348 instead of the selector control unit 148 shown in Fig. 10. The memory 124A included in the computer-readable medium 122A stores light reduction size data 134A instead of the light reduction position data 134 shown in Fig. 10 etc.

[0128] The light reduction size change control unit 348 refers to the light reduction size data 134A stored in the memory 124A, selects the size of the light reduction member 57 according to the measurement conditions of the measurement object W, and controls the operation of the light reduction size change unit 310.

[0129] The light attenuation size change unit 310 described in the embodiment is an example of a component of the size change unit that changes the area of ​​the light attenuation member that blocks the multi-wavelength light L1. The light attenuation size change control unit 348 described in the embodiment is an example of a component of the size change unit.

[0130] [Procedure of the measurement method according to the third embodiment] 17 is a flowchart showing the procedure of a measurement method according to the third embodiment. In the flowchart shown in the drawing, a light reduction size changing step S13 is executed instead of the light reduction position setting step S14 shown in FIG.

[0131] That is, when the measurement conditions of the measurement object W are acquired in the measurement condition acquisition step S12, a light reduction size change step S13 is executed. In the light reduction size change step S13, a light reduction member 57 having a size according to the measurement conditions of the measurement object W acquired in the measurement condition acquisition step S12 is selected, and the selected light reduction member is disposed at a specified light reduction position.

[0132] In the flowchart shown in Fig. 17, a light reduction size adjustment step S19 is executed instead of the light reduction position change step S18 shown in Fig. 11. In the light reduction size adjustment step S19, if the temporary measurement step S16 is determined to be No, the size adjustment of the light reduction member 57 is executed. The size adjustment of the light reduction member 57 is executed repeatedly until the temporary measurement step S16 is determined to be Yes.

[0133] The steps subsequent to the main measurement step S20 in the flow chart shown in FIG. 17 are similar to those in the flow chart shown in FIG. 11, and therefore the description thereof will be omitted here.

[0134] [Effects of the third embodiment] The measuring device 300 and the measuring method according to the third embodiment can provide the following advantageous effects.

[0135] [1] The size of the light-reducing member 57 that blocks a portion of the multi-wavelength light L1 passing through the central portion 54B of the condenser lens 54 is changed depending on the measurement conditions of the measurement object W. This makes it possible to obtain the same effects as those in the first embodiment.

[0136] [2] In the measurement device 300 and the measurement method according to the third embodiment, the size of the dimming member 57 that blocks a portion of the multi-wavelength light L1 passing through the central portion 54B of the focusing lens 54 is changed without moving the dimming member 57 in a direction parallel to the optical axis AX.

[0137] The above-described embodiment of the present invention may be modified, added, or deleted as appropriate within the scope of the gist of the present invention. The present invention is not limited to the above-described embodiment, and many modifications may be made by a person having ordinary knowledge in the relevant field within the technical concept of the present invention. [Explanation of symbols]

[0138] 10...measuring device, 11...controller, 12...light source, 14...light guiding member, 20...spectroscope, 22...spectroscope element, 24...photodetector, 50...probe, 52...probe housing, 54...condensing lens, 54B...central portion, 56...objective lens, 56A...peripheral portion, 56B...central portion, 57...light-attenuating member, 57A...light-attenuating member, 57B...light-attenuating member, 100...selector, 101...support member, 120...control unit, 122...computer-readable medium, 122A...computer-readable medium, 124...memory, 124A...memory, 126...storage, 130...program, 132...measurement data , 134...dimming position data, 134A...dimming size data, 140...light source control unit, 142...light detection signal processing unit, 144...probe drive control unit, 146...measurement condition acquisition unit, 148...selector control unit, 150...input / output interface, 152...input signal acquisition unit, 154...display control unit, 160...probe drive unit, 162...input device, 164...display, 200...measuring device, 210...moving mechanism, 212...guide, 214...carriage, 216...dimming support member, 220...control unit, 248...moving mechanism control unit, 250...probe, 300...measuring device, 31 0...beam attenuation size change unit, 320...control unit, 348...beam attenuation size change control unit, AP...aperture, AX...optical axis, C1...optical connector, C2...optical splitter, C3...optical connector, C4...optical connector, C5...optical connector, F1...optical fiber, F2...optical fiber, F3...optical fiber, F4...optical fiber, FP1...focusing position, FP2...focusing position, FP3...focusing position, FP11...focusing position, FP12...focusing position, FP13...focusing position, L1...multiple wavelength light, L2...reflected light, L10...multiple wavelength light, L11...incident light, L12...incident light, L13...incident light, L14...multiple wavelength light, L15... Incident light, L16...incident light, L17...incident light, L21...reflected light, P1...dimming position, P2...dimming position, P3...dimming position, SO...signal, SOC...output signal, SOP...output signal, W...measurement object, WP...measurement position, WS...surface, λ11...wavelength, λ12...wavelength, λ13...wavelength, S10...measurement start command acquisition process, S12...measurement condition acquisition process, S13...dimming size change process, S14...dimming position setting process, S16...temporary measurement process, S18...dimming position change process, S19...dimming size adjustment process, S20...main measurement process, S22...main measurement end determination process, S24...termination process

Claims

1. A light source that emits multi-wavelength light including a plurality of lights having mutually different wavelengths; a first optical unit that generates chromatic aberration along an optical axis with respect to the multi-wavelength light emitted from the light source; a second optical unit that focuses the multi-wavelength light in which the chromatic aberration is generated onto a measurement position of a measurement object; a light-reducing member that blocks a portion of the multi-wavelength light incident on the first optical unit, the light-reducing member being disposed at a position through which the optical axis passes; a light attenuation adjustment unit that varies an area ratio of an area where the light attenuation member blocks the multi-wavelength light to a cross-sectional area of ​​the multi-wavelength light at a position where the light attenuation member is disposed; an opening that transmits at least a portion of the multi-wavelength light that has passed through the light-reducing member; a light receiving unit for acquiring spectral information of the multi-wavelength light that has passed through the opening; A measuring device comprising:

2. The measuring device according to claim 1 , wherein the light attenuation adjustment section includes a position adjustment section that adjusts a position of the light attenuation member in a direction parallel to the optical axis.

3. A plurality of the light reducing members are provided, 3. The measurement device according to claim 2, wherein the position adjustment unit includes a selection unit that selects, from the plurality of light-attenuating members supported at different positions in a direction parallel to the optical axis, the light-attenuating member to be placed in a position that blocks the multi-wavelength light.

4. The measuring device according to claim 2 , wherein the position adjustment unit includes a moving unit that moves the light reducing member in a direction parallel to the optical axis.

5. The measurement device according to claim 1 , wherein the light reducing member is disposed between the first optical section or the second optical section and the opening.

6. The measurement device according to claim 1 , wherein the light attenuation adjustment section includes a size variable section that varies an area of ​​the light attenuating member that blocks the multi-wavelength light.

7. a measurement condition acquisition unit for acquiring measurement conditions when measuring the measurement object, The measurement device according to claim 1 , wherein the light attenuation adjustment unit varies an area ratio of the light blocking area of ​​the multi-wavelength light by the light attenuation member to a cross-sectional area of ​​the multi-wavelength light at a position where the light attenuation member is placed, in accordance with the acquired measurement conditions.

8. a probe that irradiates the multi-wavelength light in which the chromatic aberration is generated onto the measurement position of the measurement object, and into which reflected light of the multi-wavelength light irradiated onto the measurement object is incident; The probe comprises: The first optical unit; The second optical unit; The light reducing member; The measuring device according to claim 1 ,

9. The measuring device according to claim 1 , wherein the first optical section and the second optical section are integrally configured.

10. A measurement method for measuring a surface of a measurement object by irradiating the measurement object with multi-wavelength light including a plurality of light beams having mutually different wavelengths and generating chromatic aberration along an optical axis, the method comprising: The multi-wavelength light in which the chromatic aberration has been generated is condensed at a measurement position of the measurement object; a light-reducing member that blocks a part of the multi-wavelength light that is incident on a first optical unit that generates the chromatic aberration, the light-reducing member being arranged at a position through which the optical axis passes to a cross-sectional area of ​​the multi-wavelength light at a position where the light-reducing member is arranged, and an area ratio of the light-reducing member blocking the multi-wavelength light to a cross-sectional area of ​​the multi-wavelength light at a position where the light-reducing member is arranged is varied; at least a portion of the multi-wavelength light having passed through the light-reducing member passes through an aperture having a conjugate relationship with a focal position of the object to be measured; A measurement method for acquiring spectral information of the multi-wavelength light that has passed through the opening.

Images