JP2019211246A - Device and method for measurement - Google Patents

Abstract

To provide a method and a device for a higher precise measurement.SOLUTION: The present invention acquires first image data including first pattern information and relating to a first light L1 transmitting through a first object 41 in a first liquid 31, compares reference image data including the first pattern information and relating to light not transmitting through the first object and the first image data, and performs at least first processing of outputting first data on the characteristics of the first object.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a measurement method and a measurement apparatus.

  There is a method of inspecting a transparent body by transmitting light to the transparent body to be measured. A method for accurately measuring a measurement target is required.

JP 2007-285896 A

  Embodiments of the present invention provide a measurement method and a measurement apparatus that can improve the measurement accuracy of physical properties of an optical member.

  According to the embodiment of the present invention, the measurement method includes obtaining first image data relating to the first light including the first pattern information and transmitted through the first object in the first liquid. The measurement method includes the first pattern information, the reference image data relating to the light that does not pass through the first object, and the first image data are compared with each other to compare the first image data with respect to the first object characteristic. Including at least a first process of outputting data.

FIG. 1 is a schematic perspective view illustrating a measurement apparatus according to the first embodiment. FIG. 2A and FIG. 2B are schematic views illustrating operations in the measurement apparatus. FIG. 3A to FIG. 3C are schematic views illustrating the operation of the measurement apparatus according to the first embodiment. FIG. 4 is a graph illustrating characteristics of the object. FIG. 5 is a graph illustrating characteristics in the measurement method. FIG. 6 is a schematic perspective view illustrating the state of the measuring apparatus according to the second embodiment. FIG. 7A to FIG. 7C are schematic views illustrating the operation of the measurement apparatus according to the second embodiment.

Embodiments of the present invention will be described below with reference to the drawings.
The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between the parts, and the like are not necessarily the same as actual ones. Even in the case of representing the same part, the dimensions and ratios may be represented differently depending on the drawings.
In the present specification and drawings, the same elements as those described above with reference to the previous drawings are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate.

(First embodiment)
FIG. 1 is a schematic perspective view illustrating a measurement apparatus according to the first embodiment.
As shown in FIG. 1, the measurement apparatus 110 includes a light source 15, a pattern member 10, a container 30, and a processing unit 70.

  In one example, the pattern member 10 is provided between the light source 15 and the container 30. For example, the light L0 is emitted from the light source 15. The light L0 enters the pattern member 10. A part of the light L0 passes through the pattern member 10 and is emitted from the pattern member 10. In this way, the first light L1 is emitted from the pattern member 10. The first light L1 is, for example, diffused light.

  In the embodiment, the light L0 emitted from the light source 15 and reflected by the pattern member 10 may be the first light L1. The light source 15 may be placed at an arbitrary position where the first light L1 of the diffused light is obtained based on the light L0.

  The pattern member 10 includes, for example, a pattern (for example, a pattern). The pattern (for example, pattern) is used, for example, to specify the position of the emission point of the first light L1. The pattern of the pattern member 10 is imaged by the imaging unit 20. The position of the emission point of the first light L1 viewed from the imaging unit 20 is specified by the position in the image corresponding to the captured pattern.

  The pattern member 10 has, for example, a sheet shape (plate shape). The pattern member 10 may include, for example, paper or plastic. With an appropriate thickness, light can be transmitted through the pattern member 10 to produce the first light L1. For example, a pattern printed on a sheet (or plate) may be provided. If the pattern is known, the data processing speed described later may be improved. The pattern member 10 may be a metal sheet having a plurality of holes. A plurality of hole patterns may be known. The pattern may be an arbitrary pattern whose position can be specified from the imaging unit 20. The pattern may include, for example, dots arranged in a lattice pattern or dots arranged in a staggered pattern. The above pattern may include a simple pattern. The pattern may include a random pattern. The pattern may include a pattern corresponding to a landscape. In the embodiment, the pattern member 10 can be variously modified.

  The first light L1 includes first pattern information. In one example, the first pattern information is information corresponding to the pattern member 10. For example, when the pattern member 10 includes a pattern, the first pattern information includes information corresponding to the pattern. For example, the first pattern information is selected from the group consisting of an in-plane distribution of light intensity, an in-plane distribution of light wavelength distribution, and an in-plane distribution of polarized light on a plane that intersects the traveling direction of the first light L1. At least one of

  The first light L1 enters the container 30. The container 30 can be formed of, for example, glass or plastic. The container 30 can transmit the first light L1. The container 30 is substantially transparent to the first light L1. The surface of the container 30 on which the first light L1 is incident is substantially a plane. For example, the first light L1 is incident substantially perpendicular to this surface.

  A first liquid 31 is stored in the container 30. An object to be measured (for example, the first object 41) is placed in the first liquid 31. The object is, for example, an optical component (for example, a lens or a prism). At least a part of the first light L1 passes through the object. At least a part of the wavelength component included in the first light L1 passes through the object. Said object may contain at least any one of glass, a semiconductor, and resin, for example. At least a part of the object may include a solid, a liquid, or a gas. At least a part of the object may include a fluid. When the object is placed in the first liquid 31, the object is not mixed with the first liquid 31.

  The first light L1 passes through the surface of the container 30, passes through the first liquid 31, passes through the first object 41, passes through another part of the first liquid 31, and separates from the container 30. The light is emitted from the surface. The emitted first light L1 enters the imaging unit 20. The imaging unit 20 converts an image included in the first light L1 into image data. The imaging unit 20 includes, for example, a camera. For example, the imaging unit 20 may be able to acquire a still image or a moving image. For example, the imaging unit 20 includes a plurality of pixels. Image data is obtained by a plurality of pixels.

  Image data obtained by the imaging unit 20 is supplied to the processing unit 70. In the processing unit 70, various processes are performed. The result processed by the processing unit 70 may be supplied to the output device 75. The output device 75 is, for example, a display. An example of processing (for example, image processing) performed by the processing unit 70 will be described later.

  In the measurement apparatus 110, a filter 25 may be provided between the imaging unit 20 and the container 30. The filter 25 can suppress the influence of light having an unnecessary wavelength such as ambient light. For example, the filter 25 can suppress the influence of unnecessary polarization.

  For example, the splitter 26 may be provided between the container 30 and the imaging unit 20. The first light L <b> 1 is separated into a plurality of lights by the splitter 26. Some of the plurality of lights enter the imaging unit 20. Another part of the plurality of lights may be incident on another imaging unit 22. The splitter 26 is, for example, a half mirror. The splitter 26 may be a polarization splitter, for example. For example, a plurality of images having different polarization properties are obtained. A plurality of images can be obtained simultaneously or with a short time difference.

  In the embodiment, the first light L1 may not pass through the container 30. For example, the first light L1 may be incident from the upper surface of the first liquid 31, reflected by a mirror or the like placed in the first liquid 31, and incident on the first object 41. The first liquid 31 may include, for example, water or oil. The refractive index of the first liquid 31 is adjusted, for example. The first liquid 31 is a known liquid.

  Hereinafter, an example of a measurement method using the measurement apparatus 110 will be described. The following method (operation) is performed in the processing unit 70, for example.

FIG. 2A and FIG. 2B are schematic views illustrating operations in the measurement apparatus.
FIG. 2A and FIG. 2B schematically illustrate image data. In this example, two image data are illustrated as models. FIG. 2A corresponds to the image data DTa when the first object 41 has uniform optical characteristics. FIG. 2B corresponds to the image data DTb when the optical characteristics of the first object 41 are not uniform. In this example, the first object 41 is not placed in the first liquid 31 but is placed in the air.

  As shown in FIGS. 2A and 2B, patterns are observed in the image data DTa and the image data DTb. The patterns in the image data DTa and the image data DTb correspond to, for example, the brightness distribution (for example, combination) in each of the plurality of pixels. For example, as indicated by a circle PT1 in FIG. 2A and a circle PT2 in FIG. 2B, similar patterns occur in the image data DTa and the image data DTb. This pattern corresponds to a pattern (for example, a pattern) of the pattern member 10.

  Here, the position in the image data DTa of the pattern in the circle PT1 of the image data DTa is different from the position in the image data DTb of the pattern in the circle PT2 of the image data DTb. Thus, a pattern shift occurs between the two images. The shift amount ΔD of this pattern depends on the non-uniform difference in the optical characteristics of the first object 41.

  For example, the distribution of the shift amount ΔD between the plurality of pixels in the first image data DT1 and the plurality of pixels in the second image data DT2 specified from the pattern (pattern) of the pattern member 10 is calculated. The distribution of the calculated shift amount ΔD corresponds to the light deflection angle ε in the first object 41.

  For example, a plurality of pixels in one image data and a plurality of pixels in another one image data correspond to each other based on a pattern. The shift amount ΔD in these images is approximately represented by the product of the optical distance between the pattern member 10 and the first object 41 and the deviation angle ε. The optical distance between the pattern member 10 and the first object 41 is the physical distance between the pattern member 10 and the first object 41 and the space between the pattern member 10 and the first object 41. It is approximately represented by the product of the refractive index of the medium. From the calculation result of the shift amount ΔD in these images, the distribution of the deviation angle ε caused by the first object 41 can be derived. When the first light L1 passes through the container 30, the refractive index of the medium is, for example, an average refractive index of the container 30 and the first liquid 31.

FIG. 3A to FIG. 3C are schematic views illustrating the operation of the measurement apparatus according to the first embodiment.
FIG. 3A and FIG. 3B schematically illustrate image data.
As shown in FIG. 3A, the first image data DT1 related to the first light L1 is acquired. The first light L1 includes first pattern information. For example, the first light L <b> 1 is light that is emitted from the pattern member 10 and transmitted through the first object 41 in the first liquid 31. The first image data DT1 includes data of an image 41D corresponding to the first object 41.

  For example, there may be a density distribution or the like inside the first object 41. In this case, the refractive index changes according to the density distribution. When light enters such a first object 41, the optical path of the light emitted from the first object 41 changes according to the density distribution (refractive index distribution). The density distribution is, for example, a refractive index gradient. For example, when light passes through a medium having a non-uniform refractive index, if there is a refractive index gradient in the medium, the light is deflected in a direction where the refractive index is higher.

  For example, the image when there is no first object 41 has an image pattern corresponding to the pattern of the pattern member 10. At this time, for example, when the first object 41 having a density distribution (refractive index distribution) is placed on the optical path, an image pattern shifted from the pattern of the pattern member 10 is generated. This shift is based on, for example, the Schlieren phenomenon.

  For example, the image pattern based on the pattern of the pattern member 10 is compared with the image pattern when the first object 41 is placed. The deviation angle ε can be quantitatively known from the shift amounts in these image patterns. From the shift amounts in these image patterns, the density distribution (for example, the refractive index distribution) in the first object 41 may be quantitatively derived.

  In one example according to the embodiment, the first image data DT1 and the reference image data are compared. The first image data DT1 is image data relating to the first light L1 emitted from the pattern member 10 and transmitted through the first object 41 in the first liquid 31. The reference image data is image data relating to light emitted from the pattern member 10 and transmitted through the first liquid 31 but not transmitted through the first object 41. The first image data DT1 is compared with the reference image data, and first data relating to the characteristics of the first object 41 is output.

  For example, as described with reference to FIGS. 2A and 2B, the plurality of pixels in the first image data DT1 and the plurality of pixels in the reference image data are based on a pattern (pattern). Correspond. The shift amount ΔD in these images is approximately represented by the product of the optical distance between the pattern member 41 and the first object 41 and the deviation angle ε. The distribution of the deviation angle ε can be derived from the calculation result of the shift amount ΔD. The distribution of the deflection angle ε corresponds to the first data regarding the characteristics of the first object 41.

  With such a first process, the distribution of the deflection angle ε is calculated from the difference (shift amount ΔD) between the first image data DT1 and the reference image data. The distribution of the deflection angle ε is, for example, quantitative. The distribution of the deflection angle ε is related to the refractive index distribution of the first object 41, for example. From the distribution of the argument ε, the refractive index distribution in the first object 41 may be derived. From the distribution of the declination ε, the distribution of physical characteristics inside the first object 41 may be derived. The physical property may include, for example, at least one of stress, temperature, pressure, strain, and density. In embodiments, the use of polarized light derives a distribution of physical properties of at least one of stress orientation, inclusion orientation, refractive index stress coefficient, refractive index temperature coefficient, and birefringence. May be. These derivations may be performed for all pixels in the image.

  In another example according to the embodiment, another image data (second image data) may be acquired in a state in which the second object 42 (see FIG. 1) serving as a measurement reference is placed.

  As shown in FIG. 3B, the second image data DT2 related to the second light L2 is acquired. The second light L2 includes second pattern information. For example, the second pattern information is information corresponding to the pattern member 10. For example, when the pattern member 10 includes a pattern, the second pattern information includes information corresponding to the pattern. For example, the second pattern information is selected from the group consisting of an in-plane distribution of light intensity, an in-plane distribution of light wavelength distribution, and an in-plane distribution of polarized light on a plane that intersects the traveling direction of the second light L2. At least one of For example, the second light L2 is light emitted from the pattern member 10 and transmitted through the second object 42 in the first liquid 31. The second image data DT2 includes data of an image 42D corresponding to the second object 42.

  The second object 42 is, for example, a reference object in measurement. For example, the optical characteristics of the first object 41 may be different from the optical characteristics of the second object 42. For example, the first image data DT1 and the second image data DT2 are compared. Thereby, for example, the declination ε can be quantitatively known from the shift amount in the image pattern. From the amount of shift in the image pattern, for example, the difference in density distribution (refractive index distribution) between these objects can be quantitatively known.

  For example, in another example according to the embodiment, the first image data DT1 and the second image data DT2 are compared. Also in this case, the first image data DT1 is image data relating to the first light L1 emitted from the pattern member 10 and transmitted through the first object 41 in the first liquid 31. On the other hand, the second image data DT2 is image data relating to the second light L2 emitted from the pattern member 10 and transmitted through the second object 42 in the first liquid 31. Another first process for comparing the second image data DT2 and the first image data DT1 and outputting the first data related to the characteristics of the first object 41 is performed. The first data includes a distribution of differences between the deviation angle ε in the first image data DT1 and the deviation angle ε in the second image data DT2. In this case, for example, the difference in the deviation angle ε between the first object 41 and the second object 42 can be quantitatively known. For example, the difference in refractive index distribution between the first object 41 and the second object 42 can be quantitatively known.

  At least one of the reference image data and the second image data DT2 may be acquired in advance. These image data may be stored in a memory provided in the processing unit 70, for example. For example, the processing unit 70 or the like can communicate with a server or the like, and these data may be stored in a memory provided in the server. If necessary, stored data may be retrieved.

  FIG. 3C shows an example of the relationship between the characteristic variation in the object and the shift amount in the image data. The horizontal axis of FIG.3 (c) is the characteristic fluctuation | variation (DELTA) p in a target object. The variation Δp corresponds to, for example, a variation in refractive index gradient in the object. The fluctuation Δp may correspond to, for example, a density fluctuation in the object. The vertical axis represents the shift amount ΔD in the image data. In one example, the shift amount ΔD is, for example, a shift amount between the first image data DT1 and the reference image data. In another example, the shift amount ΔD is, for example, a shift amount between the first image data DT1 and the second image data DT2.

  As shown in FIG. 3C, when the characteristic variation Δp in the object is large, the shift amount ΔD in the image data is large. The shift amount ΔD is proportional to the variation Δp, for example. Based on the characteristics shown in FIG. 3C, the characteristic variation Δp (distribution) in the object can be determined from the shift amount ΔD.

  Here, the relationship of FIG. 3C is a characteristic when there is no influence of the interface between the object and the surrounding medium. Hereinafter, an example of the influence of the interface between the object and the surrounding medium will be described.

FIG. 4 is a graph illustrating characteristics of the object.
FIG. 4 exemplifies experimental results relating to the amount of image shift when an external stress is applied to an object to be measured. FIG. 4 also illustrates simulation results. The object to be measured is an acrylic resin plate. Stress (load) is applied to the plate, and a part of the plate is displaced. At this time, the shift amount in the image data of the light passing through the plate is evaluated. The horizontal axis in FIG. 4 corresponds to the distance Y (mm) between the measurement position and the load application point. The vertical axis represents the deflection angle εy (× 10 ⁻⁴ rad). The declination εy is calculated from the shift amount ΔD. The declination εy is an angle corresponding to the amount of change in the direction of light. As already described, the distribution of the deflection angle εy is obtained from the shift amount ΔD of the image data of the pattern member 10. Depending on the stress, the density distribution inside the plate changes. This change in density distribution becomes a change in refractive index distribution. In accordance with the stress, a refractive index gradient is generated inside the plate. Furthermore, the surface of the plate is deformed according to the stress, and along with this deformation, the optical path changes due to surface refraction.

  FIG. 4 shows the experimental result M1 measured in the air. As already described, FIG. 4 in which the distribution of the deflection angle εy is obtained from the shift amount ΔD of the image data of the pattern member 10 shows three characteristics S1 to S3 of the simulation. The characteristic S1 indicates the deflection angle εy of the light transmitted through the refractive index distribution inside the plate corresponding to the applied stress, and the characteristic S2 indicates the refraction of the light transmitted through the surface of the plate deformed according to the applied stress. Corresponds to the corner. The characteristic S3 is the sum of the characteristic S1 and the characteristic S2. As shown in FIG. 4, the characteristic S3 is in good agreement with the experimental result M1. As shown in FIG. 4, in the actual characteristic (experimental result M1), it can be seen that the contribution (characteristic S2) of the change in the optical path accompanying the deformation of the surface of the plate is large.

  In the embodiment, image data is acquired in a state where the first object 41 is placed in the first liquid 31. Thereby, the influence of the surface of a target object is suppressed. It is possible to provide a measuring method and a measuring apparatus that can improve the measurement accuracy of the declination generated inside the object.

  For example, the refractive index of the object is higher than the refractive index of air. The refractive index of the liquid is higher than the refractive index of air. For this reason, the influence of refraction on the surface is suppressed by acquiring image data in a state where the first object 41 is placed in the first liquid 31 compared to when the first object 41 is placed in the air. it can. When the refractive index of the first liquid 31 is close to the refractive index of the first object 41, the influence of refraction on the surface can be further suppressed.

FIG. 5 is a graph illustrating characteristics in the measurement method.
FIG. 5 shows an example of the relationship between the difference in refractive index between the first liquid 31 and the first object 41 and the shift amount in the image data. The horizontal axis represents the refractive index difference Δn. The difference Δn is, for example, the difference between the first liquid refractive index of the first liquid 31 with respect to the first light L1 and the first object refractive index of the first object 41 with respect to the first light L1. The first object refractive index is a refractive index in a state where the first object 41 has no internal stress or temperature change and the first object 41 is uniform. The vertical axis represents the shift amount ΔD in the image data. As shown in FIG. 5, when the difference Δn in refractive index is 0, the shift amount ΔD in the image data is a value ΔD0. The value ΔD0 is a value corresponding to the declination caused by the inside of the first object 41.

  In the embodiment, the refractive index difference Δn is preferably small. For example, the ratio of the absolute value of the refractive index difference Δn to the difference between the first liquid refractive index and 1 is preferably 10 percent or less, for example. Thereby, it is possible to carry out measurement with practically high accuracy. The difference Δn may be, for example, a difference between the first liquid refractive index for the first light L1 of the first liquid 31 and the first object refractive index for the first light L1 on the surface of the first object 41.

(Second Embodiment)
In the second embodiment, in addition to the measurement (first process) using the first liquid 31 described in regard to the first embodiment, the measurement using another liquid (second liquid) is performed.

FIG. 6 is a schematic perspective view illustrating the state of the measuring apparatus according to the second embodiment.
As shown in FIG. 6, a light source 15, a pattern member 10, a container 30 and a processing unit 70 are provided. In the second embodiment, the second liquid 32 is stored in the container 30. For example, the second liquid 32 is different from the first liquid 31. The refractive index of the second liquid 32 is different from the refractive index of the first liquid 31. A first object 41 (measurement object) or a second object 42 (reference object) is placed in the second liquid 32.

  Also in this embodiment, the light emitted from the pattern member 10 enters the second liquid 32 in the container 30. This light may be the same as or different from the first light L1 illustrated in FIG. Hereinafter, the light incident on the first object 41 in the second liquid 32 is referred to as the third light L3 for convenience.

  In the second embodiment, in addition to the image data (first image data DT1, reference image data, or second image data DT2) described with respect to the first embodiment, further image data (first described below). 3 image data) is acquired.

FIG. 7A to FIG. 7C are schematic views illustrating the operation of the measurement apparatus according to the second embodiment.
FIG. 7A and FIG. 7B schematically illustrate image data.
As shown in FIG. 7A, the third image data DT3 related to the third light L3 is acquired. The third light L3 is light emitted from the pattern member 10 and transmitted through the first object 41 in the second liquid 32. The third image data DT3 includes data of an image 43D corresponding to the first object 41.

  Also at this time, when light (the third light L3) enters the first object 41, the optical path of the light emitted from the first object 41 changes according to the density distribution (refractive index distribution). A shift occurs in the image pattern.

  By comparing the third image data DT3 with the reference image data already described, second data relating to the characteristics of the first object 41 can be derived. Based on the difference between the derived second data and the first data described with reference to the first embodiment, the characteristics of the first object can be derived.

  FIG. 7C illustrates characteristics in the measurement method. The horizontal axis of FIG.7 (c) is the refractive index difference (DELTA) n between a liquid and a target object. The vertical axis represents the shift amount ΔD in the image data. In the example shown in FIG. 7C, the shift amount ΔD is small when the absolute value of the refractive index difference Δn is small. As already described, the refractive index of the first liquid 31 is different from the refractive index of the second liquid 32. The difference between the refractive index of the first liquid 31 and the refractive index of the object is defined as a difference Δn1. The difference between the refractive index of the second liquid 32 and the refractive index of the object is defined as a difference Δn2. As shown in FIG. 7C, the shift amount ΔD when the difference Δn1 is the shift amount ΔD1. The shift amount ΔD when the difference Δn2 is the shift amount ΔD2. In the embodiment, the shift amount ΔD may be large when the absolute value of the refractive index difference Δn is small.

  As shown in FIG. 7C, when the relationship between the difference Δn and the shift amount ΔD is monotonically decreasing or monotonically increasing, these relationships are substantially linear when the incident angle is small. Therefore, a function of this straight line can be derived from the difference Δn1, the difference Δn2, the shift amount ΔD1, and the shift amount ΔD2. For example, the shift amount ΔD (value ΔD0) when the difference Δn is 0 can be derived.

  The first data corresponds to the difference Δn1 and the shift amount ΔD1. The second data corresponds to the difference Δn2 and the shift amount ΔD2.

  As described above, in one example according to the second embodiment, based on the difference between the first data and the second data obtained by comparing the third image data DT3 and the reference image data, the first data A second process of outputting data (third data) related to the characteristics of the object 41 can be performed. The third data corresponds to, for example, the shift amount ΔD (value ΔD0) when the difference Δn is zero.

  In another example according to the second embodiment, image data of the second object 42 in the second liquid 32 is used. For example, as illustrated in FIG. 7B, fourth image data DT4 related to the fourth light L4 emitted from the pattern member 10 and transmitted through the second object 42 in the second liquid 32 is acquired. The fourth image data DT4 includes data of an image 44D corresponding to the second object 42.

  In this other example according to the second embodiment, the fourth image data DT4 is compared with the third image data DT3 (see FIG. 7A). As already described, the third image data DT3 is image data related to the third light L3 emitted from the pattern member 10 and transmitted through the first object 41 in the second liquid 32. Second data is obtained from the fourth image data DT4 and the third image data DT3. Based on the difference between the second data and the first data, a second process for outputting data related to the characteristics of the first object 41 can be performed. Also in this case, the first data corresponds to the difference Δn1 and the shift amount ΔD1 illustrated in FIG. The second data corresponds to the difference Δn2 and the shift amount ΔD2 illustrated in FIG. 7C.

  In this other example according to the second embodiment, the difference in characteristics between the first object 41 and the second object 42 can be derived with high measurement accuracy.

  In the second embodiment, by using the first liquid 31 and the second liquid 32, even when the refractive index of these liquids does not match the refractive index of the object, the influence of the surface of the object is substantially reduced. Can be removed. Thereby, measurement accuracy can be improved.

  In the second embodiment, for example, data is calculated based on the characteristics described with reference to FIG. For example, the first liquid refractive index of the first liquid 31 with respect to the first light L1 is different from the second liquid refractive index of the second liquid 32 with respect to the third light L3. The second liquid refractive index may be the refractive index of the second liquid 32 with respect to the first light L1.

  For example, the first difference between the first liquid refractive index and the first object refractive index of the first object 41 with respect to the first light L1 corresponds to the difference Δn1 (see FIG. 7C). The second difference between the second liquid refractive index and the second object refractive index of the first object 41 with respect to the third light L3 corresponds to the difference Δn2 (see FIG. 7C). Third data is derived based on the ratio between the first absolute value of the difference Δn1 and the second absolute value of the difference Δn2.

  For example, the first difference and the second difference are positive. Alternatively, the first difference and the second difference are negative. The first difference may be positive and the second difference may be negative. The first difference may be negative and the second difference may be positive.

  In the embodiment, the first to third data may be supplied to the output device 75 (see FIG. 1 and the like). These data can be visualized and output.

  In the embodiment, the measured characteristic of the first object 41 includes the refractive index distribution of the first object 41. The measured property of the first object 41 includes a density distribution of the first object 41. In the embodiment, the light (first to fourth lights L1 to L4) emitted from the pattern member 10 is preferably diffused light. By using the diffused light, the influence of the incident angle on the object on the image data is suppressed. Thereby, higher measurement accuracy can be obtained.

  According to the embodiment, it is possible to provide a measurement method and a measurement apparatus that can improve measurement accuracy.

  In the present specification, “vertical” and “parallel” include not only strict vertical and strict parallel, but also include variations in the manufacturing process, for example, and may be substantially vertical and substantially parallel. .

  The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, regarding the specific configuration of each element such as a light source, a pattern member, a container, a liquid, an imaging unit, and a processing unit included in the measuring device, the present invention can be similarly selected by appropriately selecting from a known range by those skilled in the art. It is included in the scope of the present invention as long as the same effect can be obtained.

  Moreover, what combined any two or more elements of each specific example in the technically possible range is also included in the scope of the present invention as long as the gist of the present invention is included.

  In addition, all measurement methods and measurement devices that can be implemented by those skilled in the art based on the measurement methods and measurement devices described above as embodiments of the present invention also include the gist of the present invention. It belongs to the scope of the present invention.

  In addition, various changes and modifications can be conceived by those skilled in the art within the scope of the idea of the present invention, and these changes and modifications are considered to be within the scope of the present invention. .

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... Pattern member, 15 ... Light source, 20, 22 ... Imaging part, 25 ... Filter, 26 ... Splitter, 30 ... Container, 31, 32 ... First, second liquid, 41, 42 ... First, second object , 41D to 44D ... image, 70 ... processing unit, 75 ... output device, ΔD ... shift amount, ΔD0 ... value, ΔD1, ΔD2 ... shift amount, Δn ... difference, Δn1, Δn2 ... difference, Δp ... variation, εy ... bias 110, measuring device, DT1 to DT4, first to fourth image data, DTa, DTb, image data, L0, light, L1, L4, first to fourth light, M1, experimental results, PT1, PT2,. Circles, S1-S3 ... characteristics, Y ... distance

Claims (8)

Including first pattern information, obtaining first image data relating to first light transmitted through the first object in the first liquid,
The first image data including the first pattern information and comparing the first image data with respect to the light that does not pass through the first object is compared with the first image data to output the first data regarding the characteristics of the first object. A measurement method in which at least one process is performed. Including first pattern information, obtaining first image data relating to first light transmitted through the first object in the first liquid;
The second image data relating to the second light including the first pattern information and transmitted through the second object in the first liquid is compared with the first image data, and the characteristics of the first object are compared. A measurement method for performing at least a first process of outputting first data relating to the.   The first liquid refractive index of the absolute value of the difference between the first liquid refractive index of the first liquid for the first light and the first object refractive index of the first object for the first light. The measurement method according to claim 1, wherein a ratio to a difference between 1 and 1 is 10 percent or less. Third image data regarding the third light including the first pattern information and transmitted through the first object in the second liquid is further acquired, and the first liquid refractive index of the first liquid with respect to the first light is Unlike the second liquid refractive index for the third light of the second liquid,
Based on the difference between the first data and the second data relating to the characteristics of the first object obtained by comparing the third image data and the reference image data, the first object The measurement method according to claim 1, wherein at least a second process of outputting third data relating to characteristics is performed. Third image data regarding the third light including the first pattern information and transmitted through the first object in the second liquid is further acquired, and the first liquid refractive index of the first liquid with respect to the first light is Unlike the second liquid refractive index for the third light of the second liquid,
Second data obtained by comparing the third image data with the fourth image data including the first pattern information and relating to the fourth light transmitted through the second object in the second liquid. The measurement method according to claim 2, wherein at least a second process of outputting third data relating to the characteristic of the first object is performed based on a difference between the first data and the first data.   The first absolute value of the first difference between the first liquid refractive index and the first object refractive index of the first object with respect to the first light, the second liquid refractive index, and the first object The measurement method according to claim 4, wherein the third data is derived based on a ratio between a second object refractive index of the object with respect to the third light and a second absolute value of a second difference between the second object refractive index and the second object refractive index. .   The measurement method according to claim 1, wherein the first pattern information corresponds to a first pattern member. A light source that emits light;
A container,
A first liquid in the container;
A pattern member on which the light is incident;
A processing unit;
With
The processing unit obtains first image data relating to first light emitted from the pattern member and transmitted through a first object in the first liquid,
The processing unit compares the first image data with reference image data relating to light emitted from the pattern member and not transmitted through the first object, and obtains first data relating to characteristics of the first object. A measurement apparatus that performs at least the first process to be output.