JP2000249660A - Apparatus and method for inspection of surface - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and a method for the inspection of a surface, in which an inspection result agrees with a visual inspection result. SOLUTION: A light irradiation means 20 by which the surface of an object 1 to be measured is irradiated with light is provided. An objective lens 10 is provided. In addition, a light detecting means 30 by which an incident component in a direction parallel to the optical axis of the objective lens is detected out of reflected light, from the object to be measured, incident on the objective lens and by which its quantity of light is found is provided. The light detecting means contains a y-sensor 31 whose sensitivity is large in a green wavelength region. The component of the green wavelength region corresponds to a lightness in terms of a refractive index. Since the lightness indicates a large correlation with the surface state of the object 1 to be measured, it is possible to obtain an inspection result which corresponds to a visual inspection result.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a surface inspection apparatus and a surface inspection method. For more information,
The present invention relates to a surface inspection apparatus and a surface inspection method for quantifying a surface state of an A device, a home appliance, or the like.

[0002]

2. Description of the Related Art In the field of interior and exterior parts of automobiles, office automation, home appliances, etc., the required level of physical properties of surfaces relating to the appearance of products, specifically, scratches, unevenness, uneven gloss, uneven color, etc. It is getting stricter year by year. In particular, in the case of a product made of a synthetic resin, in addition to the various properties described above, the weld appearance, flow mark appearance, stress whitening, and the like of the product surface are significantly involved in the commercial value. Conventionally, the surface condition of such a product has been evaluated by performing a sensory test for visually ranking. However, in the sensory test, the test result is obtained only as a rank for each evaluation item,
The inability to store detailed information about the surface state, that is, the same level of information as the state seen by the naked eye, has hindered quality control and material development.

In order to solve such a problem, the surface state of a product is stored in a photograph or the like. However, since contrast differs depending on photographing conditions, printing conditions, and the like, objective data is not obtained. There has been a long-felt need for a method and apparatus capable of accurately digitizing and quantifying the surface state of products and materials.

Therefore, the present applicant has previously proposed a surface inspection apparatus and a surface inspection method capable of accurately quantifying the surface state irrespective of the shape of an object to be measured and applicable to the surface inspection of a product. (JP-A-10-318935). This includes a light source for irradiating light to the surface of the object to be measured, an objective lens opposed to the surface of the object to be measured, and receiving reflected light emitted from the light source and reflected by the surface of the object to be measured. Of the reflected light passing through the lens, a light detecting means for detecting a component incident on the objective lens in a direction parallel to the optical axis to obtain the light amount, and an optical path between the objective lens and the light detecting means are provided. And a slit provided.

In such a configuration, the light emitted from the light source is reflected on the surface of the object to be measured, and the reflected light enters the objective lens. When the reflected light enters the objective lens, the reflected light incident parallel to the optical axis of the objective lens passes through the objective lens and then enters the slit, and only the light passing through the opening of the slit is transmitted to the light detection means. The light quantity is calculated. That is, since only the component that has passed through the opening of the slit among the reflected light reflected in the direction parallel to the optical axis of the objective lens can be extracted and detected, the detection range of the reflected light on the surface of the measured object, that is, the light detection range Can be limited by the opening of the slit. Therefore, by narrowing down the light detection range with the objective lens and slit, the reflected light within the limited range can be extracted and the amount of light can be obtained, so that the surface condition of the target appearance can be quantified accurately and precisely. it can.

[0006]

In the above-described surface inspection apparatus and surface inspection method, the light detection range is narrowed down by the objective lens and the slit, so that the reflected light within the limited range is taken out, and the light amount is obtained. Although it is possible to quantify the surface state of an object to be measured based on the amount of light, the inspection result may not always match the visual result as seen by a human. Therefore, three sensors having substantially the same sensitivity as the spectral sensitivity (three sensitivities for distinguishing colors) corresponding to the human eye, that is, an x (λ) sensor having a large sensitivity mainly in the red wavelength range, A y (λ) sensor having a large sensitivity in the green wavelength region and a z (λ) sensor having a large sensitivity mainly in the blue wavelength region are prepared.
Attempts have been made to measure the sample with (λ), y (λ), and z (λ) sensors, but there have been problems with poor appearance, especially with the inability to detect weld lines and the like.

For example, when a color difference of a sample (4 cm square) having a weld line as shown in FIG. 26A is obtained, a small light receiving section 160 capable of measuring a color difference of 0.1 mm square.
There is a method of measuring the color difference of the entire surface by contacting a 4 cm square light receiving unit consisting of 000 pieces (400 × 400) with the sample. Each of the small light receiving units has three x (λ), y
Since it is composed of (λ) and z (λ) sensors, when measuring the color difference of the entire sample, an enormous sensor is required and the cost becomes high. In addition, since the calculation is required to obtain the color difference, measurement time is required. Moreover, the obtained results, for example, AB, CD
From the upper graph, the weld line portions (AB, CD)
Cannot be quantified because it is impossible to distinguish between the normal part and the intersection part of

An object of the present invention is to provide a surface inspection apparatus and a surface inspection method in which an inspection result matches a visual result.

[0009]

According to the present invention, there are provided three sensors having substantially the same sensitivity as the spectral sensitivity (three sensitivities for distinguishing colors) corresponding to the human eye, that is, a large sensor mainly in the red wavelength region. Among the x (λ) sensors having high sensitivity, the y (λ) sensors having high sensitivity mainly in the green wavelength range, and the z (λ) sensors having high sensitivity mainly in the blue wavelength range, the green wavelength Finds that the result detected only by the y (λ) sensor which has a large sensitivity in the region matches the visual result, and tries to quantify the surface state based only on the component detected by this y (λ) sensor. It is. In particular, by using only the y (λ) sensor, real-time measurement can be realized, and data can be collected by scanning the object to be measured or the optical system.
Further, by performing a relative evaluation of the brightness of a limited portion by the aperture, it is intended to prevent a measurement error due to brightness unevenness peculiar to an optical system, unlike an image analyzer.

[0010] The invention according to claim 1 (surface inspection apparatus)
A light irradiating means for irradiating light to the surface of the object to be measured, a light receiving unit arranged opposite to the surface of the object to receive light reflected from the object to be measured, and the light incident on the light receiving unit. Among the reflected light from the object to be measured, light detecting means for detecting a component incident in a direction parallel to the optical axis of the light receiving portion to obtain the light amount is provided, and the light detecting means is located in a green wavelength range. It is characterized by including a y sensor having high sensitivity, a photoelectric conversion element for converting light detected by the y sensor into an electric signal, and a signal processing unit for processing an output of the photoelectric conversion element.

Here, as shown in FIG. 3, the y sensors constituting the light detecting means are three sensors having substantially the same sensitivity as the spectral sensitivity (three sensitivities for distinguishing colors) corresponding to human eyes. That is, an x (λ) sensor having a large sensitivity mainly in the red wavelength region, a y (λ) sensor having a large sensitivity mainly in the green wavelength region, and a large sensitivity mainly in the blue wavelength region. Among the z (λ) sensors, y (λ) (hereinafter, referred to as y sensor) having a large sensitivity mainly in the green wavelength region is referred to. The irradiation angle of the light irradiated from the light irradiation means to the surface of the object to be measured is
A direction substantially perpendicular to the object to be measured, a direction oblique to the surface of the object to be measured (the angle is arbitrary, for example, 45
°), or a combination of these methods, depending on the surface condition of the object to be measured. When irradiating light from an oblique direction, the light may be irradiated in a ring shape or a semicircular shape. An objective lens, an optical fiber, or the like can be used as the light receiving unit. When an objective lens is used as the light receiving unit, the magnification of the objective lens may be appropriately selected according to the surface state of the object to be measured, but is preferably about 30 times or less. If the magnification exceeds 30 times, for example, when scanning is performed while relatively moving the object to be measured and the optical system, a measurement error due to the vertical movement of the object to be measured becomes large, and there is a possibility that the visual appearance becomes incompatible with the visual appearance. When the magnification is about 1 ×, it is expected that application to a non-contact scanning method is difficult due to a measurement error problem. desirable. When an optical fiber is used as the light receiving section, for example, an optical fiber bundle in which optical fibers exclusively for incidence and light reception are randomly bundled is preferable.

According to this invention, the light emitted from the light irradiating means to the surface of the object to be measured is reflected by the surface, and then guided to the light detecting means through the light receiving section. In the light detection means, a component in the green wavelength range is detected by the y sensor, and the component is converted into an electric signal by the photoelectric conversion element, and then processed by the signal processing unit. That is, of the light reflected on the surface of the device under test, only the component in the green wavelength range is extracted. The component in the green wavelength range corresponds to lightness in terms of reflectance, and specifically, corresponds to the Y component in the XYZ color system chromaticity diagram defined in the CIE (International Commission on Illumination) standard color system. Shows a large correlation with the surface state of the device under test, so that only the components in the green wavelength range are extracted from the light reflected by the surface of the device under test, and the inspection result corresponding to the visual result can be obtained. . Thus, more accurate quantification of the surface state such as poor appearance can be realized.

According to a second aspect of the present invention, in the surface inspection apparatus according to the first aspect, the object to be measured, the light irradiating unit, the light receiving unit, and the light detecting unit are positioned with respect to an optical axis of the light receiving unit. And a driving means for relatively moving in a perpendicular direction. Here, the driving unit may move one or both of the object to be measured and the optical system (light receiving unit, light irradiating unit, and light detecting unit),
Regarding the moving structure, a structure capable of relatively moving in one direction (for example, X direction) orthogonal to the optical axis of the light receiving unit, or a relative movement in two directions (X, Y directions) orthogonal to the optical axis. Any structure, such as a structure capable of turning around the optical axis, and the like, may be used. At this time, the relative movement speed is
Generally, it is 1 to 4000 mm / min. 1mm / mi
If it is less than n, it takes an inspection time and 4000 mm / m
This is because if the value exceeds “in”, it may not be possible to follow a change in the appearance defect. In general, when tracking a wide range of external defects, a high speed is preferable for an external defect with a large pitch size of the external defect pattern, and in a narrow range, an external defect with a very small pitch is preferable. Slow speeds are preferred. In particular, it is preferable to select the relative moving speed to be the optimum speed according to the evaluation item (inspection item).
For example, for the appearance inspection with scratches, 1 to 200 mm / mi
n, about 1-100 mm /
min, 5 for flow mark and uneven gloss inspection
It is preferably about 0 to 400 mm / min.

According to the invention, the object to be measured and the optical system (light receiving section, light irradiating means and light detecting means) are inspected while relatively moving in a direction orthogonal to the optical axis of the light receiving section. Since the brightness data on the surface of the object to be measured can be continuously detected, the appearance defect corresponding to the visual result can be grasped with higher accuracy. For example,
In the case of spot measurement, hand marks, fingerprints, and fine scratches (for example, in the case of resin molded products, irregularities caused by inorganic fillers such as talc, and fine scratches on the mold are transferred to the product), etc. Although there is a case where the image does not correspond to the visual appearance, there is a case where the appearance does not correspond to the visual appearance. However, since the entirety of the noise is clarified by using the scanning data, the appearance defect corresponding to the visual result can be grasped with higher accuracy.

According to a third aspect of the present invention, in the surface inspection apparatus according to the first or second aspect, the light detecting means is provided between the y sensor and the photoelectric conversion element or between the y sensor and the light receiving section. A variable aperture stop is provided between them, and the light receiving section is constituted by an objective lens. Here, the aperture of the stop may have any shape, and for example, an aperture having a circular opening can be used. In this case, the diameter of the opening is 0.05 to 80 mm, preferably about 0.1 to 15 mm. 0.05mm
If it is less than 3, the amount of light introduced into the light detecting means is insufficient, sensitivity is reduced, quantification is difficult, and the photoelectric conversion element is easily deteriorated. This is because if it exceeds 80 mm, the detection sensitivity for poor appearance is reduced. In addition, when inspecting an object to be measured having a grain having a large pattern pitch on the surface, it is preferable to increase the diameter of the aperture opening to widen the light detection range, so that the measured value variation is reduced. Further, when inspecting an appearance defect having a flat surface and a small pitch, it is preferable to reduce the diameter of the aperture opening and narrow the light detection range because the detection sensitivity increases.

According to this invention, only the light that has passed through the aperture of the stop is guided to the light detecting means, and the amount of the light is obtained, that is, the reflected light reflected in the direction parallel to the optical axis of the objective lens. Of these, only the components that have passed through the aperture of the stop can be extracted and detected, so that the light detection range of the reflected light on the surface of the measured object can be limited by the aperture of the stop. Therefore, by narrowing down the light detection range by the objective lens and the aperture, the reflected light within the limited range can be extracted and the amount of the reflected light can be obtained, so that the surface condition of the target appearance can be quantified accurately and precisely. it can.

According to a fourth aspect of the present invention, in the surface inspection apparatus according to any one of the first to third aspects, the light irradiation means includes a light source and illumination switching means, and the illumination switching means Is a bright-field illumination for making the light from the light source parallel to the optical axis of the light receiving unit and irradiating the object to be measured through the light receiving unit; and forming the light from the light source in a ring shape and forming the object to be measured. And dark field illumination for irradiating the optical axis of the light receiving section obliquely so that a focal point exists on the surface of the light receiving section.

According to the invention, the illumination switching means selectively uses bright-field illumination and dark-field illumination according to the surface condition of the object to be measured and the evaluation item (inspection item) focused on the surface condition. Thus, the surface state of the measured object can be quantified with higher accuracy. For example, when an object to be measured is made of a synthetic resin, when inspecting hard scratches (also referred to as whitening scratches) or black lines having a weld appearance among scratched appearances, a dark field that irradiates light from an oblique direction is used. By using illumination, an excellent correlation with the visual result is obtained. When inspecting for mild scratches (also called shiny scratches), flow marks, and uneven glossiness of the welded appearance among the scratched appearances, light is irradiated from a direction substantially perpendicular to the surface of the measured object. By using bright field illumination,
A high-precision inspection result corresponding to visual observation can be obtained for each item. In particular, in dark-field illumination, the surface of the object to be measured is irradiated with light from all directions in a ring shape.
A measurement error due to a difference in irradiation direction can be eliminated, and an excellent detection result correlated with a visual result can be obtained. That is, when light is radiated to the measured object from only one direction, the appearance defect and the like are generally directional, so that the amount of reflected light detected is different from when the light is irradiated from another direction. Yes,
In addition, since the direction in which an object to be measured is viewed in visual judgment is not always constant, irradiating light in a ring shape can eliminate variations in data depending on the irradiation direction.

The invention according to claim 5 (surface inspection method)
Inspects the surface appearance of an object to be measured using the surface inspection apparatus according to any one of claims 1 to 4. According to such an invention, the same effect as the effect described in the first aspect of the invention can be expected.

According to a sixth aspect of the present invention, in the surface inspection method according to the fifth aspect, the light from the light irradiating means includes:
The laser light is incident on the surface of the device under test at an angle substantially perpendicular to the surface of the device under test, and reflected light in a direction substantially perpendicular to the surface of the device under test is incident on the light detection unit through a light receiving unit. According to such an invention, light is incident at an angle substantially perpendicular to the surface of the device under test, and reflected light in a direction substantially perpendicular to the surface of the device under test is detected. Since the optical path is an optical path of 0-0 ° with respect to the optical axis of the light receiving unit, and the totally reflected light from the measured object is received, the evaluation item having the most correlation with the total reflected light from the measured object, for example, Mild scratches, flow marks, uneven glossiness, etc. can be accurately detected among scratched appearances.

According to a seventh aspect of the present invention, in the surface inspection method according to the fifth aspect, the light from the light irradiating means includes:
The light is incident on the surface of the object at an angle of approximately 45 °, and reflected light in a direction substantially perpendicular to the surface of the object is incident on the light detection means through a light receiving unit. According to such an invention, light is incident on the surface of the device under test at an angle of approximately 45 °, and reflected light in a direction substantially perpendicular to the surface of the device under test is detected.
Since the optical path of the light becomes an optical path of 45-0 ° with respect to the optical axis of the light receiving unit, and the diffuse reflection light from the measured object is received, the inspection item having the most correlation with the diffuse reflected light from the measured object, For example, it is possible to accurately detect hard scratches in the scratched appearance and black lines in the welded appearance.

According to an eighth aspect of the present invention, there is provided a surface inspection method for inspecting the surface appearance of an object to be measured by using the surface inspection apparatus according to the third aspect, wherein the size of the aperture of the stop and the size of the It is characterized in that the magnification of the objective lens is changed to adjust the light detection range on the surface of the measured object. According to such an invention, by changing the combination of the size of the aperture of the stop and the magnification of the objective lens, the light detection range on the surface of the object can be arbitrarily adjusted according to the surface condition of the object. Therefore, a more accurate inspection can be realized.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a surface inspection apparatus of the present embodiment. This surface inspection apparatus is used to
Objective lens 10 as a light receiving unit opposed to the surface of
Light irradiating means 20 for irradiating light to the surface of DUT 1
A light detection unit 30 that detects a component incident on the objective lens 10 in a direction parallel to the optical axis of the objective lens 10 among reflected light from the DUT 1 and obtains an amount of light; The output unit 40, the DUT 1, and the objective lens 10, the light irradiating unit 20, and the light detecting unit 30 are relatively moved in directions (X and Y directions) orthogonal to the optical axis L1 of the objective lens 10. Relative moving means 50. Although not shown, the optical system including the objective lens 10, the light irradiation means 20, and the light detection means 30 can be moved up and down in the direction of the optical axis L1 of the objective lens 10.

The light irradiating means 20 includes the objective lens 1
A light source 21 disposed on an optical axis L2 orthogonal to the optical axis L1, a collimating lens 22 disposed on the optical axis L2 and making light from the light source 21 parallel, and the optical axis L1. , L2 at the intersection of the collimator lens 2
A bright / dark field switching mechanism 26 for irradiating the object 1 with the parallel light from 2 as bright field illumination or dark field illumination, and an object to be measured by refracting the ring-shaped dark field illumination disposed around the objective lens 10. 1 and a ring-shaped dark-field illumination lens 25 for irradiating the surface of the lens 1 from an oblique direction.

Here, as the light source 21, C, D65,
D60, A, F2, F6, F7, F8, F10, F1
1, F12 (according to JIS Z8720 standard), etc., can be selected depending on the purpose. Further, as shown in FIG. 2, the light / dark field switching mechanism 26 includes the two optical axes L1,
A slide member 27 slidable in a direction orthogonal to L2 is included. The slide member 27 has a circular half mirror portion 23 for bright field illumination along the sliding direction.
And a ring-shaped complete reflection mirror section 24 having a light transmitting section 24A inside. Therefore, the slide member 2
7, a bright-field illumination for irradiating light at an irradiation angle perpendicular to the DUT 1 (an angle parallel to the optical axis L <b> 1 of the objective lens 10); It is possible to switch to dark field illumination in which light is emitted at an irradiation angle (for example, an angle of 45 ° with respect to the optical axis L1 of the objective lens 10).

More specifically, when the ring-shaped complete reflection mirror section 24 for dark field illumination is switched on the optical axis L 1, of the parallel rays from the collimating lens 22, the ring-shaped perfect reflection mirror section 24 is irradiated. Only light is reflected to form a ring, and becomes parallel to the optical axis L1 of the objective lens 10, enters the dark-field illumination lens 25, and is oblique to the optical axis L1 of the objective lens 10, for example, , 45 ° and irradiates the surface of the DUT 1. When the circular half mirror section 23 for bright field illumination is switched on the optical axis L1, of the parallel rays from the collimating lens 22, only the light irradiated on the circular half mirror section 23 is reflected and the objective lens is changed. 10 becomes parallel to the optical axis L1 and passes through the objective lens 10 with respect to the optical axis L1 of the objective lens 10.
The object 1 is irradiated at an irradiation angle of °. A plurality of types of dark-field illumination lenses 25 having different refractive indices are prepared. By appropriately selecting and using these, the irradiation angle with respect to the surface of the DUT 1, that is, the optical axis L1 of the objective lens 10 is obtained.
The irradiation angle of light with respect to can be adjusted.

The light detecting means 30 includes a y sensor (also referred to as a y filter) 31 having a large sensitivity in a green wavelength range,
A stop 32 that stops the light passing through the y sensor 31 and a photoelectric conversion element 3 that converts the light passing through the stop 32 into an electric signal.
3 and A for digitizing the output of the photoelectric conversion element 33.
The D converter 34, the input unit 35, the memory 36, the data and the like input from the input unit 35 are stored in the memory 36, and the output of the AD converter 34 is given to the output unit 40, and And a signal processing unit 37 stored in the memory 36 accordingly.

Here, the y sensor 31 is constituted by a sensor having high sensitivity in the green wavelength range. Specifically, as shown in FIG. 3, three sensors having almost the same sensitivity as the spectral sensitivity (three sensitivities for distinguishing colors) corresponding to the human eye, that is, a large sensitivity mainly in the red wavelength region. Of the x (λ) sensor having the following formula, the y (λ) sensor having a large sensitivity mainly in the green wavelength region, and the z (λ) sensor having a large sensitivity mainly in the blue wavelength region. Only y (λ) (y sensor) having a large sensitivity mainly in the green wavelength range is used. The stop 32 has a disk shape whose center is rotatably supported, and has a plurality of openings 32A and 32B having different sizes on the same circumference whose radius is the distance from the center to the optical axis L1 of the objective lens. It has. Therefore, the aperture 32
Is rotated, the size of the openings 32A and 32B on the optical axis L1 of the objective lens 10 is changed, and only the light that has passed through the openings 32A and 32B on the optical axis L1 can be guided to the photoelectric conversion element 33. . The aperture 32 of the stop 32
The shape of A and 32B is not particularly limited, and may be, for example, a circular shape or a rectangular shape.

The output means 40 comprises an XY recorder. In addition, an oscilloscope may be used, or if a personal computer or an external storage device is connected, post-processing of analog data is also possible. In addition, plane information obtained by scanning the sample in two directions of X and Y, analog output of angle dependence in rotational movement around the center of the inspection unit, output of scan data after adjusting to an arbitrary angle, and the like are provided. , Detailed information can also be obtained.

As shown in FIG. 4, the relative moving means 50 includes a base 51, a Y table 52 provided on the base 51 so as to be movable in the front-rear direction (Y direction),
A Y-direction manual adjustment knob 53 for moving the table 52 in the Y-direction; an X-table 54 provided on the Y-table 52 so as to be movable in the left-right direction (X-direction); X to move table 54 in the X direction
And a direction drive mechanism 55.

The X-direction drive mechanism 55 is rotatably supported on the Y-table 52 in parallel with the moving direction (X-direction) of the X-table 54 and a part thereof is connected to the X-table 5.
4 and the feed screw shaft 56
And a motor 57 for rotationally driving the motor. Therefore, when the motor 57 is driven, the X table 54 screwed with the feed screw shaft 56 is moved at a constant speed in the X direction with the rotation of the feed screw shaft 56. Thus, the surface of the DUT 1 placed on the X table 54 can be scanned at a constant speed.

Next, a surface inspection method using the surface inspection apparatus of the present embodiment will be described. First, the DUT 1 is set to X
While being placed on the table 54 and observing the surface of the DUT 1 through an eyepiece (not shown), the magnification of the objective lens 10 is selected, and the stop 32 is rotated to position the objective lens 10 on the optical axis L1 of the objective lens 10. The openings 32A and 32B are positioned to adjust the light detection range on the surface of the DUT 1.

The illumination from the light source 21 is controlled by sliding the slide member 27 of the light / dark field switching mechanism 26 in accordance with the inspection item focused on the surface condition of the DUT 1 and the surface condition of the DUT 1. Switch to brightfield illumination or darkfield illumination. At this time, the irradiation angle of the light in the dark-field illumination is determined based on the selected angle.
By setting the refractive index of 5 to correspond to visual observation, for example, it is set to 45 °. The setting of the refractive index of the dark-field illumination lens 25 is performed by mounting an objective lens barrel including the dark-field illumination lens 25 having a desired refractive index.

When light is emitted from the light source 21, the emitted light passes through the collimator lens 22 and becomes parallel light, and is emitted to the surface of the DUT 1 via the bright / dark field switching mechanism 26. This irradiation light is reflected on the surface of the DUT 1, and a component of the reflected light parallel to the optical axis of the objective lens 10 passes through the objective lens 10, and then only a component in the green wavelength range is detected by the y sensor 31. Detected and passed. The component that has passed through this enters the apertures 32A and 32B located on the optical axis L1, and only the component of the incident light that has passed through the apertures 32A and 32B is detected by the photoelectric conversion element 33, and the light amount is the current value. Is converted to This current value is digitized by the A / D converter 34, and when no arithmetic processing is performed, the current value is output and displayed as it is from the output means 40.

At this time, of the light reflected on the surface of the device under test 1, only the component in the green wavelength range is the photoelectric conversion element 33.
It is detected by. The component in the green wavelength range corresponds to lightness in reflectance, and since this lightness has a large correlation with the surface state of the DUT 1, the current value (accordingly, The output result from the output means 40 changes.
Therefore, an inspection result corresponding to the visual result is obtained. Such an inspection is performed in a certain range on the surface of the DUT 1,
Alternatively, when the measurement is performed on the entire surface, that is, when the evaluation is performed by scanning, the inspection is performed while moving the DUT 1 by moving the relative movement unit 50 in the horizontal direction at the time of measurement.

In the light detecting means 30, the photoelectric conversion element 3
The light quantity of the light received at 3 is converted into a current value, and the current value is digitized by the A / D converter 34 and sent to the signal processing unit 37. In the signal processing unit 37, the digitized current value is stored in the memory 36 as necessary, and is output and displayed from the output unit 40.

According to the present embodiment, the light emitted from the light irradiating means 20 is reflected by the surface of the device under test 1, passes through the objective lens 10, and is guided to the light detecting means 30. A component in the green wavelength range is detected by the sensor 31, the component is converted into an electric signal by the photoelectric conversion element 33, and then processed by the signal processing unit 37. In other words, of the light reflected on the surface of the device under test 1, only components in the green wavelength range are extracted. The components in the green wavelength range are
It has been found that the lightness corresponds to the lightness, and this lightness has a great correlation with the visual appearance of the surface state of the DUT 1. Based on this finding, more accurate quantification of the surface state such as poor appearance can be realized.

Further, relative movement means for relatively moving the DUT 1 and the optical system, that is, the light irradiation means 20, the objective lens 10, and the light detection means 30 in a direction orthogonal to the optical axis of the objective lens 10. 50, the DUT 1
The inspection can be performed while relatively moving the optical system and the optical system. That is, since the brightness data on the surface of the device under test 1 can be continuously detected, the appearance defect corresponding to the visual result can be grasped with higher accuracy. For example, in the case of spot measurement, hand marks, fingerprints, and fine scratches (for example, in the case of a resin molded product, irregularities caused by an inorganic filler such as talc, and fine scratches of a mold are transferred to a product in the spot measurement). ), Etc., may not correspond to the visual appearance,
If you use scanning data, the whole noise will be clear,
The appearance defect corresponding to the visual result can be grasped with higher accuracy.

Further, since the stop 32 is provided in the optical path between the y sensor 31 and the photoelectric conversion element 33, the aperture of the stop 32 among the reflected light reflected in the direction parallel to the optical axis L1 of the objective lens 10 is provided. Since only the components that have passed through the aperture 32A or the aperture 32B can be extracted and detected, the detection range of the reflected light on the surface of the DUT 1, that is, the light detection range is reduced by 32.
Opening 32A, 32B. Therefore, by narrowing down the light detection range by the objective lens 10 and the stop 32, reflected light within a limited range can be extracted and its light amount can be obtained, so that the surface state can be strictly and accurately quantified. In particular, when measuring the surface state of the DUT having a complicated shape, even when the low-magnification objective lens 10 is used to prevent the defocus, the light detection range on the surface of the DUT 1 is controlled by the aperture 32. Since the surface of the DUT 1 can be finely divided into a plurality of detection ranges and detected at a low magnification, the surface state of the DUT 1 can be quantified with high precision.

Since the light path between the light source 21 and the DUT 1 is provided with the bright / dark field switching mechanism 26, the observation condition selected by visually observing the surface condition of the DUT 1 for a desired evaluation item is determined. By selectively using bright-field illumination and dark-field illumination according to the angle, the surface state of the DUT 1 can be quantified with higher accuracy. In particular, in dark-field illumination, since the surface of the DUT 1 is irradiated with light from all directions in a ring shape, measurement errors due to differences in the irradiation direction can be eliminated, and excellent detection results correlated with visual results can be obtained. Can be That is, when light is irradiated on the DUT 1 from only one direction, the amount of light detected may be different from that when the light is irradiated from the other direction, and the DUT 1 is viewed by visual judgment. Since the direction is not always constant, by irradiating the light in a ring shape, variation in data depending on the irradiation direction can be eliminated, and the surface state can be observed under the same conditions as visual observation.

Also, by changing the magnification of the objective lens 10 and the size of the apertures 32A and 32B of the stop 32, the light detection range on the surface of the DUT 1 can be adjusted, so that a more accurate inspection can be realized. .

It should be noted that the present invention is not limited to the above-described embodiment, but includes other configurations that can achieve the object of the present invention, and also includes the following modifications and the like. That is, although the stop 32 of the embodiment is formed in a disk shape, the present invention is not limited to this. For example, openings are provided in parallel along the longitudinal direction of the belt-like member, and the belt-like member is formed along the longitudinal direction. By sliding, an opening to be arranged on the optical axis L1 of the objective lens 10 may be selected.
Alternatively, a plurality of apertures having different aperture sizes may be prepared, and the aperture size on the optical axis L1 may be changed by appropriately selecting and mounting the apertures. Further, the aperture of the stop may be formed at a position deviated from the optical axis L1 of the objective lens 10 as necessary. However, 0-0 ° optical path measurement and 4
In the case of 5-0 ° optical path measurement, the aperture of the stop is preferably on the optical axis L1.

In the above embodiment, the bright / dark field switching mechanism 26
Is used to switch between bright-field illumination and dark-field illumination. However, the illumination switching means is not limited to the structure using the bright-dark field switching mechanism 26, and is different from, for example, the bright-dark field switching mechanism 26 of the above-described embodiment. A structure using a slide having a shape may be employed, or dark-field illumination may be performed by arranging an illumination fiber annularly around the objective lens. In short, the structure is arbitrary as long as bright-field illumination and dark-field illumination can be performed, and an existing structure may be appropriately selected and used.

In the above embodiment, the DUT 1 is moved with respect to the optical system (the objective lens 10, the light irradiation means 20, and the light detection means 39).
May be fixed, and the optical system may be moved, or both may be moved. In the above-described embodiment, the y sensor 31 is disposed between the bright / dark field illumination switching mechanism 26 and the aperture 32. However, the y sensor 31 may be disposed between the aperture 32 and the photoelectric conversion element 33. . Note that, between the y sensor 31 and the aperture 32,
The y sensor 31 and the photoelectric conversion element 33 may be connected by an optical fiber. Further, in the above-described embodiment, the light receiving unit is configured by the objective lens 10, but may be configured by an optical fiber bundle. In this case, the aperture 32 may not be required in some cases.

Further, a lens made of a diffusion material is arranged at the position of the ring-shaped dark-field illumination lens 25 so that the ring-shaped dark-field illumination from the bright-dark-field illumination switching mechanism 26 is diffused and illuminated on the DUT 1. Is also good. In the above embodiment,
The surface inspection device was configured using an existing polarizing microscope.
Instead of using the polarizing microscope, the surface inspection apparatus may be configured by assembling respective members such as an objective lens, a light irradiation unit, a light detection unit, and a relative movement unit. In addition,
The type of the DUT 1, specifically, the material, shape, size,
The color and the like are arbitrary.

[0046]

EXAMPLE A sample made of a synthetic resin was used as the DUT 1 of the above embodiment, and the appearance of a scratch, the appearance of a flow mark, the appearance of a weld, the whitening of a stress, the appearance of a flat scratch due to the difference in the color of the base material, the plated molded product The appearance of each was evaluated. [Evaluation of Scratched Appearance] The surface of a test piece molded from PP (polypropylene) / talc-based material was made a flat surface, and a sample A with mild scratches on this flat surface and a sample with hard scratches (whitening scratches) B was prepared. Also, P
The surface of the test piece formed from the P / talc-based material was used as a grain (uneven pattern) surface, and a sample C having a mild scratch on the grain surface and a sample D having a hard scratch were prepared. The scratching tester uses a pencil hardness tester manufactured by Yasuda Seiki Co., Ltd. When a mild scratch is made, a metal rod with a large radius is used instead of a pencil, and when a hard scratch is made, the tip of a mechanical pencil is used. Metal parts were adopted. Load is 100gf, 300gf, 500gf, 700g
f, 900 gf at 5 points.

First, the samples A and B were subjected to surface inspection using the surface inspection apparatus of the above embodiment. This inspection is performed when light is irradiated from the light irradiation unit to the samples A and B at an oblique angle of 45 ° (45-0 ° optical path).
In the case where the light was irradiated perpendicularly to the samples A and B from the light irradiating means (0-0 ° optical path), the light detection range (inspection area) was narrowed down to the range of 0.2 mm in diameter. The measurement was performed while scanning A and B in a direction perpendicular to the direction of the damage. The measurement conditions are as follows. Magnification of objective lens: 5x, Aperture aperture: 1mm diameter circle (inspection area; 0.2m diameter
m), scanning speed: 9.4 cm / min (chart speed of XY recorder: 20 cm / min)

In this test, the measurement conditions for the 0-0 ° optical path and the 45-0 ° optical path were initially set as follows. Under the measurement conditions in the 0-0 optical path (type of light source, diameter of stop, magnification of objective lens, etc.), the white standard plate is irradiated with light, and the brightness of the reflected light at that time can be changed so as to be 100. Set appropriate measurement conditions. For example,
When the aperture diameter and the magnification of the objective lens are fixed among the measurement conditions, the brightness of the white standard plate becomes 100 by appropriately increasing or decreasing the resistance to the current obtained by converting the reflected light from the white standard plate. Adjust as follows. When the magnification of the objective lens is not limited, the magnification is changed, and if necessary, the distance between the white reference plate and the objective lens is changed, so that the brightness of the white reference plate is set to 100. For measurements in the 45-0 optical path,
Under the measurement conditions, the initial setting can be performed by the same method as described above. However, the measurement is performed in the 45-0 ° optical path with the initial setting in the 0-0 ° optical path. In this case, the obtained value is multiplied by 13. This is because in this case, the initial value of the 45-0 optical path becomes equal to the value obtained by measurement under the condition.

As a result, FIG. 5 and FIG. 6 show the results of the evaluation of the damage load dependency of Sample A (flat surface: mild scratch), which was inspected under the measurement conditions of the 45-0 ° optical path and the 0-0 ° optical path. Show. In the case of the 0-0 optical path, the lightness of the damaged portion becomes high. Lightness tends to be low in a high load region, with a peak at 500 gf. This indicates that in the area where the load is high, the scratched surface is rough. 45-0 °
In the light path, the brightness decreases and the change is small. There is almost no load dependency. When visually observed in the same visual field, the damaged part shows 0
Unlike the −0 ° optical path, it looks relatively dark and reproduces the data trend. Therefore, when a mild scratch is made on the plane, it is understood that measurement in the 0-0 ° optical path is preferable.

Sample B (flat surface: hard scratched)
7 and 8 show the results of the evaluation of the load dependency on the scratches, which were inspected under the measurement conditions of the 45-0 ° optical path and the 0-0 ° optical path. In the case of a hard flaw, the flaw is relatively roughened and diffused light becomes dominant. 0-0 ° optical path and 45-
Load dependence data is obtained for both the 0 ° optical path. Therefore, when a hard scratch is made on the plane, any evaluation can be made, but it can be seen that the 45-0 ° optical path can be detected with higher accuracy. Here, by using the following brightness change rate, comparison between data having different optical paths is also possible.
It is possible in response to visual observation. Lightness change rate = (| defective part lightness-normal part lightness |) / normal part lightness Normal part lightness is the average of the lightness of a part without flaws, and corresponds to M described in FIGS. 6 and 8. The defective portion lightness is the lightness of a portion having a flaw, and corresponds to m1 to m5 described in FIGS. 6 and 8. For example, when viewed from the same angle as the measurement optical path, the samples in FIGS. 5 to 8 stand out in the order of FIGS. 7, 6, 8, and 5. The hard scar of FIG. 8 is less noticeable than the mild scar of FIG.
It is inconspicuous when viewed in the −0 ° optical path, and mild scratches are 0-0
° This is due to being noticeable when viewed in the optical path. The brightness change rate of each sample in FIGS. 5 to 8 is 15%, 54%,
125% and 29%. When arranged in descending order of the lightness change rate, FIGS. 7, 6, 8, and 5 match the visual result.

Next, the samples C and D were subjected to surface inspection using the surface inspection apparatus of the above embodiment. In this inspection, since the pitch of the grain pattern is large, if the inspection area is reduced as in the case of plane evaluation (objective lens magnification: 5 times, diaphragm diameter: 1 mm in diameter → inspection area: 0.2 in diameter)
mm), the aperture diameter becomes 15 mm because the grain shape causes disturbance.
And the measurement conditions for the planar inspection are the same except that the inspection area is 3 mm in diameter.

As a result, with respect to the sample C (textured surface: mild scratch), the evaluation results of the scratch load dependency, which were inspected under the measurement conditions of the 45-0 ° optical path and the 0-0 ° optical path, are shown in FIGS. Shown in In addition, FIGS. 11 and 12 show the results of the evaluation of the damage load dependency of the sample D (textured surface: hard damage), which was inspected under the measurement conditions of the 45-0 optical path and the 0-0 optical path. In the case of 0-0 ° optical path, mild scratch,
The load dependence is generally reproduced with hard scratches, but the degree of dependence is small. In the case of the 45-0 optical path, mild scratches are not detected, but hard scratches clearly show load dependency, and it can be confirmed that these results correspond to visual observations. Therefore, in the case of a mild scratch on the textured surface, measurement in the 0-0 ° optical path is preferable, and in the case of a hard scratch, measurement in the 45-0 optical path is preferable. It turns out that it is.

[Evaluation of Flow Mark Appearance] The flow mark refers to a poor appearance due to uneven glossiness consisting of a high gloss portion and a low gloss portion as shown in FIG. Here, a sample E having a flat surface and a flow mark on the flat surface is shown.
And a sample F whose surface is a textured surface and a flow mark appears on the textured surface, light is irradiated from the light irradiating means to the samples E and F substantially perpendicularly, and a light detection range (inspection area) ) Is 0.2mm in diameter (aperture aperture: 1m in diameter)
m) In a state of 3 mm (aperture opening: diameter 15 mm), inspection was performed while scanning in the direction shown in FIG. Other measurement conditions are as follows. Magnification of objective lens: 5 times, scanning speed: 9.4 cm / min (chart speed of XY recorder: 6 cm / min)

As a result, for the sample E (plane),
The flow mark evaluation results in a state where the inspection area is 0.2 mm in diameter and a state in which the inspection area is 3 mm in diameter are as follows:
FIG. 14 and FIG. In addition, FIGS. 16 and 17 show flow mark evaluation results of the sample F (textured surface) in a state where the inspection area is 0.2 mm in diameter and in a state where the inspection area is 3 mm in diameter. These are all 0-0 optical paths. On a flat surface, when the inspection area is 0.2 mm in diameter (see FIG. 14), disturbances such as irregularities due to fine scratches, dirt, fingerprints, inorganic fillers such as talc, etc. are detected. When the aperture diameter is 15 mm and the inspection area is 3 mm in diameter (see FIG. 15), it can be seen that data excluding the influence of disturbance can be obtained. On the grained surface, the disturbance due to the grain shape becomes more dominant than dirt or fingerprints (see FIG. 16). Similarly, when the aperture diameter is 15 mm and the inspection area is 3 mm (see FIG. 17), the influence of the disturbance is eliminated. It can be seen that the obtained data can be obtained. Therefore, the flow mark appearance is 0 in both the flat surface and the grained surface.
It can be seen that in the measurement in the −0 ° optical path, the inspection area should be increased. It is preferable to reduce the inspection area of a sample which is expected to have no or little disturbance since the flow mark can be detected with higher sensitivity.

[Evaluation of Weld Appearance] The appearance of the weld was evaluated by using a flat sample of what was formed by counterflow from both side gates. PP / talc-based materials
As shown in FIG. 18, it is known that a black line is generated at the tip of the confluence, and a gloss change occurs near the black line. Here, for the G sample and the H sample having different tendencies, light is irradiated from the light irradiation unit to each sample G and H at an oblique angle of 45 ° (45-0 ° optical path).
In the case where light is irradiated perpendicularly to each sample G and H from the light irradiation means (0-0 ° optical path), the light detection range (inspection area) is narrowed down to a range of 2 mm in diameter, and each sample is sampled. The measurement was performed while scanning G and H in the direction of the arrow in FIG. The measurement conditions are as follows. Magnification of objective lens: 5 times, Aperture aperture: 1 mm diameter circle (inspection area; 0.2 m diameter
m), scanning speed: 9.4 cm / min (chart speed of XY recorder: 6 cm / min)

As a result, for sample G, 45-0
19 and 20 show the results of the weld appearance evaluation performed under the measurement conditions of the 0 ° optical path and the 0-0 ° optical path. 21 and 22 show the evaluation results of the wellness appearance of the sample H, which were inspected under the measurement conditions of the 45-0 ° optical path and the 0-0 ° optical path. In the evaluation of the 0-0 optical path, it can be seen that the brightness decreases as approaching the AC section, and the leading end rises. In Sample G, the degree of gloss unevenness near the weld was high, but the degree of rise of the black line was small. Sample H shows the opposite trend. In the evaluation of the 45-0 optical path, a white haze (appearing whitish) is reproduced in the vicinity of the weld portion, the brightness is reduced at the tip, and a black line is reproduced. Also,
It can be seen that the tendency is different between Sample G and Sample H. Accordingly, it can be seen that, among the weld appearances, the 45-0 optical path is good for the black line, and the 0-0 optical path is good for the uneven gloss.

[Evaluation of Stress Whitening] Two samples I and J were used in which an Izod specimen was whitened by hitting an Izod without a notch.
The measurement was performed while scanning the samples I and J such that the whitened portion passed under the measurement conditions of the 5-0 optical path. The measurement conditions are as follows. Magnification of objective lens: 5 times, Aperture aperture: 1 mm diameter circle (inspection area; 0.2 m diameter
m), scanning speed: 9.4 cm / min (chart speed of XY recorder: 6 cm / min)

As a result, for Samples I and J, 45
FIGS. 23 and 24 show the evaluation results of the wellness appearance under the measurement conditions of the −0 ° optical path. Therefore, it can be understood that the stress whitening can be measured in the 45-0 optical path.

[Evaluation of Appearance of Scratched Plane by Difference in Color of Substrate]
For the sample B, the color of the substrate was changed (natural, dark brown, dark blue), and the inspection shown in FIG. 7 was performed. FIG. 25 shows the result. Even if the color changes, it can be seen that the flaw is detected. That is, it can be understood that the surface state can be detected with high accuracy regardless of the color of the base material by inspection using the apparatus of the present embodiment. Here, when these results are represented by a brightness change rate, 3.2% is obtained for 50%, and 50% for 50%.
% Was 60%, which was confirmed to correspond to the visual result. In particular, if the lightness change rate is used as an index, comparison between data having different optical paths can be made corresponding to the visual result.
The lightness change rate is given by: lightness change rate = (| defective part lightness−normal part lightness |) / normal part lightness.

[Evaluation of Appearance of Plating Molded Product] (Samples) Samples K and L having the following compounding ratio were obtained by the following production method. Sample K: polyphenylene sulfide (semi-linear type T1 manufactured by Topren Co., Ltd.) 50 wt% calcium carbonate (SL2000 manufactured by Takehara Chemical Industry Co., Ltd.)
Average particle size: 3.5 μm) 50 wt% Sample L: polyphenylene sulfide (Semi-linear type T1 manufactured by Topren Co., Ltd.) 40 wt% calcium carbonate (SL2000 manufactured by Takehara Chemical Industry Co., Ltd.)
Average particle size 3.5μm) ... 60wt%

(Production method) After uniformly mixing using a Henschel mixer, a twin screw extruder (TEM35 manufactured by Toshiba Machine Co., Ltd.)
Using B), melt-knead at 300 to 350 ° C. to form pellets, and then use the obtained pellets in a 50 t injection molding machine (J50E-P manufactured by Nippon Steel Works) to make a mirror-finished flat plate mold (flat plate). (Size: 80 × 80 × 2 mm thick), set cylinder temperature 280-330 ° C., nozzle temperature 310-330 ° C., mold temperature 130-135 ° C. to obtain injection molded product, Vacuum deposition (about 1
(Thickness: 00 nm) to obtain samples K and L.

(Measurement Method) Measurement Method of the Present Invention In the inspection apparatus of the present embodiment, the aperture opening is set to a diameter of 15 m.
m circle (inspection area: diameter 3 mm), 45-0 ° optical path,
The lightness of the samples K and L was measured under measurement conditions without scanning. Reflection measurement method of JIS-K-7105 Image clarity tester (model ICM-1) manufactured by Suga Test Instruments Co., Ltd.
, The image clarity of the samples K and L was measured. This measuring method is a reflection method according to JIS-K-7105. Since an image (reflection image larger than a specular reflection image) in which the reflection image of the light source is diffused due to the reflection performance of the reflector can be seen, the optical slit (constant lattice fringe) is used. Of the amount of light received (the image is diffused, the amount of light blocked by the grid is large) and the relative value (C value) with respect to the mirror surface is evaluated. That is, samples K and L are set so that the incident angle of the light source is 45 °, and an optical slit (an optical comb width of 1.0 mm is adopted) is set perpendicular to the direction of the reflection angle of 45 °. Furthermore, a light receiver is set ahead, an image of the light source is projected on the optical slit, the slit is moved in the setting direction, and the minimum amount of light detected by the light receiver through the slit is defined as the maximum reflectance M, Maximum light intensity to minimum reflectance m
Image clarity (C value) = (M−m) / (M + m) × 100
(%).

(Evaluation Results) For samples K and L,
As a result of the measurement according to the measurement method of the present invention, JIS-K-
Table 1 shows the order of good visual appearance as a result of measurement by the reflection measurement method of No. 7105. Since the sample having a good appearance, that is, the sample K has less diffused light substantially perpendicular to the measurement surface, the brightness is reduced. JIS-K-710
Even with the difference in image clarity that cannot be determined by the reflection measurement method of 5,
It can be seen that the measurement method of the present invention can be distinguished and matches the visual result.

[0064]

[Table 1]

[0065]

As described above, according to the present invention,
Of the light reflected on the surface of the device under test, only the component in the green wavelength range was extracted and processed to inspect the surface of the device under test for poor appearance. Only components in the green wavelength range corresponding to lightness that have a strong correlation with the surface state are extracted and inspected, so that inspection results corresponding to visual results can be obtained, and quantification of surface conditions such as poor appearance. Can be realized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of a surface inspection apparatus of the present invention.

FIG. 2 is a perspective view showing components of a light irradiation unit of the embodiment.

FIG. 3 is a diagram illustrating a y-sensor according to the embodiment.

FIG. 4 is a perspective view showing a relative moving unit of the embodiment.

FIG. 5 is a diagram showing the results of evaluation of the load dependency on a flaw when a flat flaw (mild flaw) is measured along a 45-0 optical path using the surface inspection apparatus of the embodiment.

FIG. 6 is a view showing the results of evaluation of the load dependency on a scratch when flat scratches (mild scratches) are measured in the 0-0 ° optical path using the surface inspection apparatus of the embodiment.

FIG. 7 is a diagram showing the results of evaluation of the load dependency on a scratch when flat scratches (hard scratches) are measured along the 45-0 optical path using the surface inspection apparatus of the embodiment.

FIG. 8 is a diagram showing the results of evaluation of the load dependency on a scratch when flat scratches (hard scratches) are measured in the 0-0 optical path using the surface inspection apparatus of the embodiment.

FIG. 9 is a view showing the results of evaluation of the load dependency on the scratch when the scratch on the grained surface (mild scratch) is measured along the 45-0 optical path using the surface inspection apparatus of the embodiment.

FIG. 10 is a view showing the results of evaluation of the load dependency on the scratch when the scratch (mild scratch) on the textured surface is measured along the 0-0 ° optical path using the surface inspection apparatus of the embodiment.

FIG. 11 is a diagram showing a result of evaluation of the dependency on a flaw load when a flaw on a textured surface (hard flaw) is measured in a 45-0 ° optical path using the surface inspection apparatus of the embodiment.

FIG. 12 is a view showing a result of evaluation of the dependency on a flaw load when a flaw (hard flaw) on a textured surface is measured along a 0-0 ° optical path using the surface inspection apparatus of the embodiment.

FIG. 13 is a perspective view showing a sample used for evaluating the appearance of a flow mark.

FIG. 14 shows a flow mark of a plane (inspection area: 0.2 mm in diameter) of 0-0 using the surface inspection apparatus of the embodiment.
FIG. 7 is a diagram showing a flow mark evaluation result when measured in an optical path.

FIG. 15 is a view showing a flow mark evaluation result when a flat (inspection area: diameter: 3 mm) flow mark is measured along a 0-0 ° optical path using the surface inspection apparatus of the embodiment.

FIG. 16 shows a flow mark on a grained surface (inspection area: 0.2 mm in diameter) set to 0- using the surface inspection apparatus of the embodiment.
The figure which shows the flow mark evaluation result at the time of measuring in a 0 degree optical path.

FIG. 17 shows a flow mark on a grained surface (inspection area: diameter 3 mm) of 0 to 0 ° using the surface inspection apparatus of the embodiment.
The figure which shows the flow mark evaluation result at the time of measuring in an optical path.

FIG. 18 is a perspective view showing a sample used for evaluation of weld appearance.

FIG. 19 is a view showing a weld appearance evaluation result when a weld appearance of a sample G is measured along a 45-0 ° optical path using the surface inspection apparatus of the embodiment.

FIG. 20 is a view showing a weld appearance evaluation result when a weld appearance of a sample G is measured along a 0-0 ° optical path using the surface inspection apparatus of the embodiment.

FIG. 21 is a diagram showing a weld appearance evaluation result when a weld appearance of a sample H is measured along a 45-0 ° optical path using the surface inspection apparatus of the embodiment.

FIG. 22 is a view showing a weld appearance evaluation result when a weld appearance of a sample H is measured along a 0-0 ° optical path using the surface inspection apparatus of the embodiment.

FIG. 23 is a view showing a stress whitening evaluation result when the stress whitening of the sample I was measured along a 45-0 ° optical path using the surface inspection apparatus of the embodiment.

FIG. 24 is a view showing a stress whitening evaluation result when the stress whitening of the sample J is measured along a 45-0 ° optical path using the surface inspection apparatus of the embodiment.

FIG. 25 is a view showing the evaluation result of a flat scratch when the sample B is inspected by changing the color of the base material using the surface inspection apparatus of the embodiment.

FIG. 26 is a diagram when a weld line is inspected by x, y, and z sensors.

[Explanation of symbols]

 Reference Signs List 1 object to be measured 10 objective lens 20 light irradiation means 21 light source 26 light / dark field switching mechanism (illumination switching means) 30 light detection means 31 y sensor 32 stop 32A, 32B opening 33 photoelectric conversion element 37 signal processing unit 50 relative movement means (driving means)

Claims (8)

[Claims] A light irradiating means for irradiating the surface of the object with light; a light receiving unit disposed opposite to the surface of the object to receive light reflected from the object; And a light detecting means for detecting a component incident in a direction parallel to an optical axis of the light receiving portion of the reflected light from the object to be measured to obtain the amount of light. It includes a y sensor having high sensitivity in a wavelength region, a photoelectric conversion element for converting light detected by the y sensor into an electric signal, and a signal processing unit for processing an output of the photoelectric conversion element. Surface inspection equipment. 2. The surface inspection apparatus according to claim 1, wherein the object to be measured and the light irradiating unit, the light receiving unit, and the light detecting unit are relatively moved in a direction orthogonal to an optical axis of the light receiving unit. A surface inspection apparatus comprising a driving unit for causing the surface inspection to be performed. 3. The surface inspection device according to claim 1, wherein the light detection unit has a variable aperture between the y sensor and the photoelectric conversion element or between the y sensor and the light receiving unit. A surface inspection apparatus comprising: a diaphragm; and the light receiving unit is configured by an objective lens. 4. The surface inspection apparatus according to claim 1, wherein the light irradiating unit includes a light source and an illumination switching unit, and wherein the illumination switching unit includes a light from the light source. Is bright field illumination that irradiates the device under test through the light receiving unit in parallel with the optical axis of the light receiving unit, and that the light from the light source is formed in a ring shape and the surface of the device under test has a focal point As described above, the surface inspection apparatus switches between dark-field illumination and light emitted obliquely to the optical axis of the light receiving unit. 5. A surface inspection method for inspecting the surface appearance of an object to be measured using the surface inspection device according to claim 1. 6. The surface inspection method according to claim 5, wherein the light from the light irradiating unit is incident on the surface of the measured object at an angle substantially perpendicular to the surface of the measured object. A surface inspection method, wherein reflected light in a substantially vertical direction is incident on the light detecting means through a light receiving section. 7. The surface inspection method according to claim 5, wherein the light from the light irradiating unit is incident on the surface of the object to be measured at an angle of approximately 45 °, and is incident on the surface of the object to be measured. A reflected light in a substantially vertical direction is incident on the light detecting means through a light receiving section. 8. A surface inspection method for inspecting the surface appearance of an object to be measured using the surface inspection apparatus according to claim 3, wherein the size of the aperture of the stop and the magnification of the objective lens are changed. Adjusting the light detection range on the surface of the object to be measured.