JP2000171216A - Sample measuring instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the sample measuring instrument which can accurately measure the edges, outlines, shapes, sizes, etc., of various samples irrelevantly to the kinds of the samples such as whether they are transparent or opaque. SOLUTION: This instrument is equipped with a transmission lighting system 10 which observes a sample S through transmission according to light transmitted through the sample, a vertical illumination system 20 which observes the sample in vertical illumination according to light reflected by the sample, a detection unit 30 which detects light from the sample, an arithmetic unit 40 which measures the sample by processing the detection signal from the detection unit as specified, and a birefringence element 6 which can selectively switch the vertical illumination observation and transmission observation and splits the vertical illumination light from the vertical illumination system into an ordinary light beam and an extraordinary light beam having mutually orthogonal vibration directions at the time of the vertical illumination observation. Here, when the vertical illumination observation is performed, the reflected light from the sample is converted by the detection unit 30 into an electric signal and the arithmetic unit 40 processes the electric signal as specified to calculate the chromaticity value of the reflected light and measures the sample according to the chromaticity value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sample measuring apparatus for measuring edges, contours, shapes, dimensions, and the like of a sample (for example, various parts of an industrial product).

[0002]

2. Description of the Related Art For example, Japanese Patent Application Laid-Open No. 5-99619 discloses an XY stage 202 movable in a direction perpendicular to the optical axis of an objective lens 201 as shown in FIG. A transmission illumination system provided at a position facing the objective lens 201 with respect to the XY stage 202;
There is disclosed an edge detection device including a detection optical system provided on the opposite side to 1.

The transmission illumination system includes a light source 203, a collector lens 204, and a condenser lens 205. The detection optical system includes an imaging lens 206,
A pinhole 207 and a photodetector 208 are provided.

In such an edge detecting device, the light emitted from the light source 203 is once formed into an image at the front focal position 209 of the condenser lens 205 by the collector lens 204, and then converted into a parallel light beam by the condenser lens 205. The non-transparent sample set on the XY stage 202, that is, the subject 210 is Koehler-illuminated.

[0005] Diffracted light generated from the subject 210 is captured by the objective lens 201, and then an enlarged image of the subject 210 is projected on the pinhole 207 by the imaging lens 206. Then, the luminous flux passing through the pinhole 207 is
It is incident on the photodetector 208 behind it. At this time, the subject 2
10 image crosses the pinhole 207 and the photodetector 2
08 and the output changes.

The output of the photodetector 208 changes according to the position of the subject 210. FIG. 3A shows the subject 210.
The relationship between the position of the subject 210 and the output of the photodetector is shown. The position of the subject 210 is positive in the direction in which the subject 210 moves left and right in FIG. 2, and the output of the photodetector 208 is
Standardized to "1".

When the image of the subject 210 does not hang on the pinhole 207 at all, the output of the photodetector 208 becomes "1".
The output of the photodetector 208 gradually decreases as the image of the subject 210 hangs on the pinhole 207, and when the entire image of the subject 210 hangs on the pinhole 207, the output of the photodetector 208 Becomes “0”.

In particular, as shown in FIG. 3B, when the image 210a of the subject 210 is exactly half the pinhole 207, the output of the photodetector 208 is considered to be "0.5" ( FIG.

In the above-described edge detecting device, the object 21
While moving 0, the output of the photodetector 208 is
The position of “0.5” is determined as the edge of the subject 210. Then, by determining the position where the edge of the subject 210 is detected and the amount of movement of the XY stage 202 in combination, the outer shape and the hole diameter of the subject 210 are measured.

As another prior art, for example, Japanese Patent Application Laid-Open No. 7-239212 discloses a position detecting device having a configuration as shown in FIG.

In this position detecting device, the illumination light 411 emitted from the light source 401 enters the polarizer 403 via the condenser 402, and then only linearly polarized light in a given direction is extracted. After the extracted linearly polarized light is reflected from the beam splitter 404, the two polarization inspection lights 411 a and 411 b whose polarization planes are orthogonal to each other and laterally shifted by a small amount by the Wollaston prism 405.
And irradiates the sample 412 via the objective lens 406.

The reflected light reflected from the sample 412 is taken in by the objective lens 406 and the Wollaston prism 405
After the two polarization inspection lights 411a and 411b are combined in the same optical path, the light passes through the beam splitter 404 and enters the analyzer 407. At this time, the analyzer 40
7, the two polarization inspection lights 411a, 411b
Based on the optical characteristics of the analyzer 407, the polarized light components interfere with each other based on the optical characteristics of the analyzer 407, and as a result, a polarized light interference light 411c having a phase difference corresponding to the ratio of the unevenness of the sample 412 is obtained. Then, the polarization interference light 411c is formed as an image of the irradiation position on the light receiving surface 409a of the photoelectric detector 409 by the imaging lens 408.

As the characteristics of the image of the irradiation position formed on the light receiving surface 409a, the image of the plane portion of the sample 412 has a polarization interference intensity of "0" and is in a dark state because no detection signal is output. . On the other hand, the image of the uneven portion of the sample 412 is
An image is formed as a bright line having a predetermined intensity, and a detection signal corresponding to the image is output. The output detection signal is converted into an electric signal corresponding to the light intensity distribution of the polarization interference light 411c, and then sent to the signal processing means 410, where the edge (step) of the uneven portion of the sample 412 is detected.

As an edge detection method, for example, a method of determining an intensity peak of a detected signal and judging a position corresponding to the peak as an edge, or fitting an appropriate function such as a quadratic function near the intensity peak is used. Performing a method to determine the peak center of the fitted function as an edge, or after determining a specific threshold, find the position where the intensity value exceeds the threshold on the left and right of the intensity peak,
There is a method of determining one of the obtained positions or the center of both positions as an edge.

[0015]

However, the edge detecting device disclosed in Japanese Patent Application Laid-Open No. 5-99619 has a problem.
Since the transmitted illumination is used, only the shape and size of the contour of the subject can be measured. For example, it is not possible to measure the shape or the dimension of a projection in a hole or depression that does not penetrate. Furthermore, since the edge and the like of the subject 210 are measured based on the intensity of the light amount obtained by the photodetector 208 of the detection optical system, when there is unevenness in the reflectance of the subject 210, The measurement value fluctuates due to the unevenness and the like, and it becomes difficult to accurately measure the edge and the like.

On the other hand, the position detecting device disclosed in Japanese Patent Application Laid-Open No. 7-239212 is similar to the edge detecting device disclosed in Japanese Patent Application Laid-Open No. 5-99619.
Since the edge (step) is detected based on the intensity of the light amount obtained in step 9, the detected value is easily affected by the unevenness of the reflectance of the sample 412 or the like. Further, a reference position (a position where no phase difference occurs) on the sample 412 is set to a dark state, and an edge (step) is generated based on the intensity of light generated by the light and dark.
, The amount of retardation must be adjusted in order to create a dark state in preparation for measurement. In this case, for example, in measurement of a sample having a standard in a shape represented by a wafer or the like or a sample having a constant thickness,
Although the retardation adjustment requires only one initial setting,
For example, for samples having different shapes, such as general metal parts, and for samples whose thickness variation is relatively large compared to the dimensional accuracy of a wafer or the like, the retardation adjustment must be performed for each measurement of each sample. It takes time to prepare for measurement, and as a result, measurement efficiency is reduced.

The present invention has been made to solve such a problem, and an object of the present invention is to determine the edge, contour, shape, size, and the like of various samples regardless of the type of the sample, such as transparent or opaque. It is an object of the present invention to provide a sample measuring device capable of measuring accurately.

[0018]

In order to achieve the above object, a sample measuring apparatus according to the present invention includes a transmission illumination system for performing transmission observation on a sample based on light transmitted through the sample, Based on the reflected light reflected from the sample, an epi-illumination system for performing epi-illumination observation on the sample, a detection unit that detects transmitted light or reflected light from the sample and outputs a detection signal, and By performing predetermined arithmetic processing on the output detection signal, an arithmetic unit capable of measuring a sample, it is possible to selectively switch between epi-illumination observation and transmission observation, and it is also possible to perform epi-illumination observation during epi-illumination observation. An observation system switching element capable of dividing incident illumination light from the illumination system into an ordinary ray and an extraordinary ray whose vibration directions are orthogonal to each other is provided. When switched to the active state, the reflected light from the sample is converted into an electrical signal by the detection unit, and the arithmetic unit performs a predetermined arithmetic process on the electrical signal to calculate a chromaticity value of the reflected light. The sample is measured based on the chromaticity value.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A sample measuring apparatus according to one embodiment of the present invention will be described below with reference to FIG.

As shown in FIG. 1, the sample measuring apparatus according to the present embodiment includes a sample holding stage 1 on which a transparent or non-transparent sample S can be selectively placed. A rotary revolver 5 to which a plurality of objective lenses 2 of different magnifications can be attached is provided on the upper side of 1 so that the sample S can be observed at a desired magnification.

The sample holding stage 1 is configured to be movable along two axes (X axis and Y axis) perpendicular to the optical axis (Z axis) of the objective lens 2. The stage 1 has a function of reading the amount of movement thereof with high accuracy and is supported by a mirror base 3 having strong rigidity.

The mirror base 3 has an optical axis (Z axis) of the objective lens 2
The revolver 5 is provided with an arm 4 which is movable in the direction and has a function of reading the amount of movement with high precision.
Supported on the side. In this case, the arm 4 is connected to the optical axis (Z
By moving the objective lens 2 in the (axial) direction, the focal position of the objective lens 2 with respect to the sample S can be adjusted.

Such a sample measuring apparatus includes a transmission illumination system 10 for performing transmission observation on the sample S based on transmitted light transmitted through the sample S, and a sample illumination system based on reflected light reflected from the sample S. An epi-illumination system 20 for performing epi-illumination observation on S, a detection unit 30 that detects transmitted light or reflected light from the sample S and outputs a detection signal thereof, and a detection signal output from the detection unit 30 An arithmetic unit 4 capable of measuring edges, contours, shapes, dimensions, and the like of the sample S by performing predetermined arithmetic processing.
0 is provided.

The transmission illumination system 10 is provided on the mirror base 3 below the sample holding stage 1 and includes a transmission observation light source 11 for performing transmission observation, a collector lens 12, and a condenser lens 13. Have been. In the transmitted illumination system 10, the transmitted illumination light from the transmission observation light source 11 is once passed through the condenser lens 1 by the collector lens 12.
After the image is formed at the front focal position of the condenser lens 3, the condenser lens 1
The sample 3 is Koehler-illuminated by 3.

The epi-illumination system 20 is provided on the upper surface side of the arm 4 (the surface opposite to the surface on which the revolver 5 is arranged). The epi-illumination system 20 includes an epi-illumination observation light source 21 for performing epi-illumination observation, and an epi-illumination observation light source 21.
Collimator lens 22 that converts incident illumination light from
And a polarizer 2 capable of extracting linearly polarized light in an arbitrary direction from the epi-illumination light emitted from the epi-illumination observation light source 21
3, an optical path bending element 24 such as a half mirror for aligning the optical axis of the objective lens 2 with the optical axis of the epi-illumination system 20, and the objective lens 2 with the optical path bending element 24 interposed therebetween.
, And an analyzer 25 arranged so as to satisfy the crossed Nicols with the polarizer 23, and an imaging lens 26.

In the optical path between the objective lens 2 and the imaging lens 26, a Nomarski prism or the like is positioned such that the crystal axis is inclined by 45 ° with respect to the polarization direction obtained by the polarizer 23. Birefringent element 6 is arranged. The birefringent element 6 is configured to be movable in a direction indicated by an arrow in the drawing between a position in the optical path between the objective lens 2 and the imaging lens 26 and a position outside the optical path. By inserting and removing the element 6 with respect to the optical path, it is possible to selectively switch between epi-illumination observation and transmission observation.

That is, the birefringent element 6 functions as an observation system switching element for selectively switching between incident-light observation and transmission observation. Specifically, when the birefringent element 6 is positioned in the optical path, the epi-illumination observation for the sample S is enabled, and the epi-illumination observation light source 21, the collimating lens 22,
The combination of the birefringent element 6 and the objective lens 2 enables the Nomarski illumination of the sample S.
On the other hand, when the birefringent element 6 is removed from the optical path, the sample S
Is ready for transmission observation.

The detection unit 30 includes an optical path splitting element 31 typified by a half mirror or the like for splitting light from the sample S into an observation optical path and a detection optical path to be described later, and reflects light in a red wavelength range or more. The first that transmits light below the green wavelength range
And a second wavelength selecting element 3 that reflects light in the green wavelength range or more and transmits light in the blue wavelength range or less.
And an objective lens 2 on each optical path branched by the first and second wavelength selection elements 32 and 33.
In the position conjugate with the rear focal position, a sample measurement area is defined, and pinholes 34a, 34b for cutting noise information from the front and rear surfaces of the focal position of the objective lens 2 are defined.
34b and 34c are arranged. Further, the detection unit 30 receives the light passing through these pinholes 34a, 34b, 34c, and outputs detectors 35a, 35 capable of outputting an electric signal corresponding to the amount of received light (light receiving intensity).
b, 35c are provided, and each pinhole 34 is provided.
a, 34b, and 34c are positioned so that their centers coincide with the optical axis of the objective lens 2.

The arithmetic unit 40 is electrically connected to the detection unit 30 via the cable 7 and includes an arithmetic circuit 4 including storage media 42 to 45 and a difference circuit 46.
1 is provided. The arithmetic unit 40 can measure the edge, contour, shape, size, and the like of the sample S by performing various arithmetic processes on the electric signals output from the detectors 35a, 35b, and 35c. ing.

An eyepiece 9 for visual observation or image observation using a two-dimensional light receiving element such as a CCD camera is provided in the lens barrel 8, and this lens barrel 8 is composed of the objective lens 2 and the eyepiece. 9 is connected to the detection unit 30 so as to coincide with the optical axis 9.

Next, the operation of the sample measuring device will be described.

First, the operation of arranging the birefringent element 6 in the optical path between the objective lens 2 and the imaging lens 26 and performing observation of incident light on the sample S will be described.

The epi-illumination light emitted from the epi-illumination observation light source 21 is converted into parallel light via a collimating lens 22.
After the polarizer 23 extracts only the linearly polarized light component in an arbitrary direction, the optical path bending element 24 bends the optical path by 90 degrees and enters the birefringent element 6. The incident illumination light of the linearly polarized component incident on the birefringent element 6 is divided by the birefringent element 6 into an ordinary ray and an extraordinary ray whose vibration directions are orthogonal to each other. The ordinary light beam and the extraordinary light beam are projected onto the pupil position of the objective lens 2 by projecting the filament images of the two epi-illumination observation light sources 21 slightly shifted according to the amount of sharing of the birefringent element 6. Nomarski lighting.

After the reflected light from the sample S is captured by the objective lens 2, it is combined on the same optical path in the birefringent element 6. At this time, when there is an edge (step) in the sample S in the illumination field, a phase difference corresponding to the ratio occurs at a portion where the edge (step) exists. The reflected light synthesized on the same optical path by the birefringent element 6 passes through the optical path bending element 24 while maintaining the ordinary light component and the extraordinary light component, and then is analyzed by the analyzer 25 out of the ordinary light component and the extraordinary light component. Only components that pass through photons 25 interfere with each other.

After passing through the imaging lens 26, a part of the interference light is converted by the optical path splitting element 31.
Light is guided to a lens barrel 8 for visual or image observation,
The remaining interference light is guided to the detection optical path in the detection unit 30. The interference light guided to the lens barrel 8 is formed as a sample image on the retina of the observer by the eyepiece 9, and the sample S can be visually observed based on the sample image. On the other hand, the interference light guided to the detection optical path is
First, the light is incident on a first wavelength selection element 32 that reflects light in the red wavelength range or more and transmits light in the green wavelength range or less.

In the red wavelength interference light reflected from the first wavelength selection element 32, only the reflected light component reflected on the focal plane of the objective lens 2 passes through the pinhole 34a, and the detector 35
a, is converted into an electric signal (Rsig) corresponding to the amount of received light (light receiving intensity), and then transferred to the arithmetic unit 40 via the cable 7.

On the other hand, the interference light of the green wavelength range or less that has passed through the first wavelength selection element 32 then reflects the light of the green wavelength range or more and transmits the light of the blue wavelength range or less. The light enters the selection element 33.

In the green wavelength interference light reflected from the second wavelength selection element 33, only the reflected light component reflected on the focal plane of the objective lens 2 passes through the pinhole 34b, and the detector 35
b, is converted into an electric signal (Gsig) corresponding to the amount of received light (light receiving intensity), and then transferred to the arithmetic unit 40 via the cable 7.

On the other hand, of the interference light of the blue wavelength transmitted through the second wavelength selection element 33, only the reflected light component reflected on the focal plane of the objective lens 2 passes through the pinhole 34c and is received by the detector 35c. After being converted into an electric signal (Bsig) corresponding to the amount of received light (received light intensity), the signal is transferred to the arithmetic unit 40 via the cable 7.

The electrical signals thus transferred one by one are subjected to predetermined arithmetic processing in the arithmetic circuit 41 of the arithmetic unit 40. Specifically, XY chromaticity values (x _i, y _i)
Is calculated. The XY chromaticity value is the X that quantifies all colors.
The Y chromaticity diagram defines a value that depends only on hue and chroma and does not depend on luminance. The XY chromaticity value can be obtained by the following equations (1) and (2). .

[0041]

(Equation 1)

Hereinafter, the arithmetic processing of the arithmetic unit 40 will be specifically described.

Here, first, the electric signal (Rsig ₁ ,
Gsig ₁ and Bsig ₁ ) are transferred, and the XY chromaticity values calculated by performing arithmetic processing on the electric signals based on the above equations (1) and (2) are represented by (x ₁ ,
Y ₁ ), the XY chromaticity value (x ₁ , Y ₁ ) is stored in the first storage medium 42. Then, the XY chromaticity values (x ₂ , y ₂ ) calculated from the next transferred electric signals (Rsig ₂ , Gsig ₂ , Bsig ₂ ) are stored in the second storage medium 43. Subsequently, the difference between the chromaticity values stored in the first and second storage media 42 and 43 (Δx ₁₂ = x
₂₋ x ₁ , Δy ₁₂ = y ₂ −y ₁ ) is calculated, and its value is stored in the first difference storage medium 44.

The next transferred electric signal (Rsig
_The XY chromaticity values (x ₃ , y ₃ ) calculated from ( ₃ , Gsig ₃ , Bsig ₃ ) are further stored in the first storage medium 42, and then stored in the first and second storage media 42, 43. (Δx ₂₃ = x ₃ −x ₂ , Δy ₂₃ = y)
₃₋ y ₂ ) is calculated, and its value is stored in the second difference storage medium 45. Then, in the difference circuit 46,
Color difference ΔE ｛= (Δx ₂₃ −Δx ₁₂ ) ² + (Δy ₂₃ −Δ
y ₁₂ ) ² ｝ is derived.

Such a calculation process is always repeated, and when the sample S is being moved, the measurement is determined by the sizes of the pinholes 34a, 34b, 34c and the respective magnifications of the objective lens 2 and the imaging lens 26. Only at the moment when the edge (step) passes through the spot, the color difference ΔE> 0. However, when the sample S on the sample holding stage 1 is not moved or when there is no edge (step) during the movement, the color difference ΔE =
It becomes 0.

Accordingly, the distance from the point where the color difference ΔE> 0 is satisfied to the point where the next color difference ΔE> 0 is the interval between the edge (step) and the contour on the sample S.

According to the above-described epi-illumination observation of the sample S, the use of the epi-illumination light enables accurate detection of the edges (steps) and contours of the transparent and opaque sample S and the edge ( This makes it possible to accurately measure the shape other than the step) and the contour, for example, the shape of a protrusion (in a depression) that is buried in the shape or contour of a hole that does not penetrate, and the dimensions thereof. In addition, by using the XY chromaticity values that are hardly influenced by the change in the amount of light, the sample S can be accurately measured without being affected by the output fluctuation of the epi-illumination observation light source 21 or the change in the reflectance of the sample S. Becomes possible. Furthermore, since "setting of a threshold value" required when measuring the sample S based on a change in the light amount is not necessary, the work efficiency in the sample measurement can be improved.

Next, the operation of removing the birefringent element 6 from the optical path between the objective lens 2 and the imaging lens 26 and performing transmission observation on the sample S will be described.

The light emitted from the transmission observation light source 11 is
After an image is once formed on the front focal position of the condenser lens 13 by the collector lens 12, the condenser lens 13
Is converted into a parallel light beam, and the sample S set on the sample holding stage 1 is subjected to Koehler illumination.

The transmitted light transmitted through the sample S is transmitted to the objective lens 2
After passing through the optical path bending element 24, the light passes through the analyzer 25 and further passes through the imaging lens 26, and then the light path splitting element 31 partially or partially transmits the light for visual observation or image observation. The remaining transmitted light is guided to the above-described detection optical path. The transmitted light guided to the lens barrel 8 is formed as a sample image on the retina of the observer by the eyepiece lens 9, and the sample S can be visually observed based on the sample image. On the other hand, the transmitted light guided to the detection optical path projects an enlarged image of the sample S on the respective pinholes 34a, 34b, 34c by the imaging lens 26. And these pinholes 34a, 34
b, 34c pass through the respective light detectors 35a, 35c.
The light is incident on 35b and 35c. At this time, an electric signal corresponding to the amount of received light is output from each of the photodetectors 35a, 35b, and 35c, and transferred to the arithmetic unit 40 via the cable 7.

In the arithmetic unit 40, the photodetectors 35a,
Predetermined arithmetic processing is performed on the electric signals from 35b and 35c. As an example, it is assumed that the arithmetic circuit 41 sums up the electric signals from the photodetectors 35a, 35b, 35c and performs a predetermined operation on the total electric signal.
In this case, the image of the sample S is pinholes 34a, 34b, 3
4c, the respective photodetectors 35a, 35b, 3
The amount of light incident on 5c changes, and its output changes. At this time, since the output of the total electric signal also changes, the edge (step), the contour, and the like of the sample S can be measured by detecting the change. For example, the maximum value and the minimum value of the change of the total electric signal may be detected, and when an intermediate value is detected, it may be determined as an edge (step) or a contour of the sample S.

In this case, for example, one photodetector 35a
The method of detecting a change in the electrical signal output from the sample S can also be determined as an edge (step) or contour of the sample S in the same manner as described above.

In the embodiment described above, the revolver 5 is not always necessary, and can be omitted according to the application. In this case, there is an effect that the entire apparatus can be provided at low cost.

The arm 4 and the epi-illumination system 20 need not always be separate bodies. In this case, there is an effect that the weight of the entire apparatus can be reduced, and a factor that the optical axis shifts can be minimized.

Further, in order to cut off information which becomes noise from the front and rear surfaces of the focal position of the objective lens 2, the pinholes 34a, 34b and 34c are not necessarily required, and a variable aperture may be used. In this case, the size of the aperture can be changed in a fine metal part such as a general metal part, so that the sensitivity of edge detection can be freely selected, and effects such as an increase in measurement efficiency can be obtained.

The present invention is not limited to the above-described embodiment, but can be variously modified without departing from the gist of the present invention.

For example, pinholes 34a, 34b,
34c is preferably configured such that the size of the light passage path can be arbitrarily varied. Because
Even if the surface of the sample S is a rough surface having a fine uneven shape and all surfaces are regarded as edges (steps), the size of the light passage path can be increased by increasing the size of the light passage path.
This is because erroneous detection is reduced and detection accuracy can be improved.

In view of the gist of the present invention, if an epi-illumination system is provided, the object can be achieved.

That is, the sample measuring apparatus of the present invention detects the reflected light from the sample and the reflected light from the sample based on the reflected light reflected from the sample, and outputs the detection signal. A detection unit for outputting, a calculation unit capable of measuring a sample by subjecting a detection signal output from the detection unit to a predetermined calculation process, and an incident illumination light from an incident illumination system whose oscillation directions are mutually different. It has an optical element that can be divided into orthogonal ordinary rays and extraordinary rays.The reflected light from the sample is detected by the detection unit via the optical element, and is converted into an electric signal by this detection unit. The arithmetic unit may be configured to perform a predetermined arithmetic process on the electric signal, calculate a chromaticity value of the reflected light, and measure the sample based on the chromaticity value.

Also in this configuration, the pinholes 34a, 34b, and 34c may be configured so that the dimensions of the light passage can be arbitrarily changed.
With this configuration, erroneous detection is reduced as described above, and detection accuracy can be improved.

[0061]

According to the present invention, there is provided a sample measuring apparatus capable of accurately measuring edges, contours, shapes, dimensions, and the like of various samples regardless of the type of the sample, such as transparent or opaque. It is in.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a sample measuring device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a conventional edge detection device.

FIG. 3A is a diagram illustrating a relationship between a position of a subject and an output of a photodetector, and FIG. 3B is a diagram illustrating a state in which an image of the subject is just half of a pinhole.

FIG. 4 is a diagram showing a configuration of a conventional position detection device.

[Explanation of symbols]

 Reference Signs List 6 birefringent element 10 transmission illumination system 20 epi-illumination illumination system 30 detection unit 40 arithmetic unit S sample

Continued on the front page F term (reference) 2F065 AA12 AA21 AA51 BB22 BB24 DD06 FF01 FF44 FF49 FF53 FF67 HH13 HH15 JJ01 JJ05 JJ09 JJ12 JJ15 LL00 LL04 LL12 LL20 LL22 LL30 LL33 Q23 Q12 Q24 QQ12

Claims (3)

[Claims] 1. A transmission illumination system for performing transmission observation on a sample based on transmitted light transmitted through a sample, and an epi-illumination system for performing epi-illumination observation on a sample based on reflected light reflected from the sample. A detection unit that detects transmitted light or reflected light from a sample and outputs a detection signal thereof, and performs a predetermined arithmetic processing on the detection signal output from the detection unit to measure the sample Arithmetic unit, and can selectively switch between epi-illumination observation and transmission observation, and at the time of epi-illumination observation, divides epi-illumination light from the epi-illumination system into ordinary rays and extraordinary rays whose vibration directions are orthogonal to each other. And an observation system switching element capable of performing reflection observation from the sample when the observation system switching element switches the state to the epi-illumination observation mode. Is converted into an electrical signal Te, the arithmetic unit, by performing predetermined arithmetic processing on the electric signal, it calculates the chromaticity value of the reflected light,
A sample measuring device for measuring a sample based on the chromaticity value. 2. When the observation system switching element is switched to a state where transmission observation is possible, transmitted light from the sample is:
It is converted into an electric signal by the detection unit, and the arithmetic unit performs predetermined arithmetic processing on the electric signal, calculates a change in the amount of transmitted light, and measures the sample based on the change in the amount of light. The sample measurement device according to claim 1. 3. The arithmetic unit calculates a color difference from a change in chromaticity value in a state where the observation system switching element switches to a state in which epi-illumination observation is possible, and calculates a sample based on the change in the color difference. The sample measuring apparatus according to claim 1, wherein the measurement is performed.