JPH07306157A - Method and device for defect inspection - Google Patents

Abstract

PURPOSE:To improve the reliability of a method and device for defect inspection by making defects and non-defects which cause signal changes against the ground signal level at a normal part distinguishable and bringing the discriminating level closer to an artificial inspection level. CONSTITUTION:A defect inspection device is provided with an illuminating means 31 which illuminates a surface to be inspected with illuminating light, detecting means 32 which receives reflected light from the surface to be inspected and obtains DC output signals and AC output signals by performing photoelectric conversion on the received reflected light, and defect discriminating and processing mean 33 which discriminates defects and non-defects from each other by combining primary processing for extracting the outputting direction and time width of signals against the DC output signal level obtained from reflected light from the normal part of the surface to be inspected and secondary processing for judging the continuity of coordinates on the surface to be inspected front which AC output signals higher than a threshold are generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a defect inspecting apparatus for optically inspecting defects on the surface of an object and discriminating between defects and non-defects.

[0002]

2. Description of the Related Art As a defect inspection apparatus for optically detecting a surface defect, as disclosed in, for example, Japanese Patent Application Laid-Open No. 5-322791, when a surface to be measured has a defect, reflected light is generated because of the defect. By utilizing the characteristic that the diffusion of transmitted light changes and the amount of light received by the photoelectric converter increases or decreases with respect to the level of the amount of light from a normal part, the surface to be measured is irradiated with, for example, laser light, and the reflected light is photoelectrically converted. The electric signal received by the converter is obtained according to the amount of incident light, compared with a predetermined reference level, and a defect is judged by the presence or absence of a signal change above a predetermined level.
When the amount of ground composition on the surface to be measured is large, grades were judged by having multiple comparator levels and judging defects when several signals exceeding the threshold were collected. Did not do.

[0003]

In the conventional defect inspection apparatus, since a defect is judged by the presence or absence of a signal change of a predetermined level or more, if there is a signal change even if it is a non-defect, the defect and the non-defect are detected. There is a problem in that it cannot be determined.

For example, when optically inspecting for defects such as dents and scratches on the surface of a copper clad laminate, it is regarded as a good product in terms of appearance inspection even though there is a change in reflected light intensity on the surface to be measured. Due to the presence of parts such as light spots and marks on the surface roughness measuring jig, it was not possible to distinguish between defects and non-defects in the grade determination of the sensor signal.

Further, in the conventional optical inspection machine, when the reflected light intensity changes, it is once discharged as a defective product and then re-inspected and sorted again by human eyes. I couldn't skip it.

Further, when high-frequency lighting and an incandescent lamp are used for illumination and a line image sensor takes an image, both defect and non-defect signals come out in the same direction, which makes it difficult to discriminate between defects and non-defects.

The present invention has been made in view of the above points. It is possible to discriminate between a defect and a non-defect having a signal change with respect to a normal portion formation signal level, and bring the discrimination level close to an artificial inspection level. An object of the present invention is to provide a defect inspection method and a defect inspection device that can improve reliability.

[0008]

In order to solve the above-mentioned problems, the defect inspection method of the present invention according to claim 1 irradiates the surface to be inspected with illumination light and receives the light reflected from the surface to be inspected. A photoelectric conversion is performed to obtain a DC output signal and an AC output signal, and a signal output direction and a signal time width with respect to the DC output signal level due to reflected light from a normal portion of the surface to be inspected are extracted 1.
Subsequent processing and determining the continuity of coordinates on the surface to be inspected where a signal exceeding the threshold value is generated in the AC output signal 2
It is characterized in that a defect and a non-defect are discriminated by combining the following processes.

In the defect inspection method according to the second aspect of the present invention, when the surface to be inspected is a copper foil, the illumination light is laser flying spot light, and the incident angle to the surface to be inspected is 15 to 15.
55 ° range, specular reflection light component received angle range 15 °
The feature is that light is received within.

In the defect inspection method according to the third aspect of the invention, the surface to be inspected is irradiated with illumination light, and when the surface to be inspected is a copper foil, the illumination light is made into laser flying spot light, and the surface to be inspected is irradiated. The incident angle is set in the range of 15 to 55 °, the regular reflection light component is received within the reception angle range of 15 °, and the reflected light from the surface to be inspected is photoelectrically converted to obtain a DC output signal and an AC output signal. Of the DC output signal and the AC output signal, the dent defect and the scratch system are discriminated depending on whether the DC output signal level due to the reflected light from the normal portion of the surface to be inspected is the positive side or the negative side. The non-defect light spot, the non-defect flaw and the defect scratches are detected by the primary processing for performing the following and the secondary processing for extracting the defect flaws in the flaw system by the time width comparator and determining the continuity of the coordinates on the inspection surface. It is characterized by making a distinction.

According to a fourth aspect of the present invention, there is provided a defect inspection apparatus in which an irradiation means for irradiating a surface to be inspected with an illuminating light and a reflected light from the surface to be inspected are received and photoelectrically converted to generate a DC output signal and an AC output signal. Detecting means, a primary process for extracting a signal output direction and a signal time width with respect to the DC output signal level by reflected light from a normal portion of the surface to be inspected, and a signal in the AC output signal exceeding a threshold value. Is combined with a secondary process for determining the continuity of the coordinates on the surface to be inspected, and a defect determination processing unit for determining a defect and a non-defect is provided.

According to a fifth aspect of the defect inspection apparatus of the present invention, the illumination light is laser flying spot light, the incident angle on the surface to be inspected is in the range of 15 to 55 °, and the specular reflection light component is in the light receiving angle range 15. It is characterized by receiving light within °.

According to a sixth aspect of the defect inspection apparatus of the present invention, the illumination light is a laser flying spot light, the irradiation means for setting the incident angle on the surface to be inspected to be in the range of 15 to 55 °, and the specular reflection light component. A regular reflection light receiving section for receiving light within a light receiving angle range of 15 ° is provided, the surface to be inspected is irradiated with the illumination light, and the light reflected from the surface to be inspected is photoelectrically converted to generate a DC output signal and an AC output signal. Of the detecting means to obtain, the DC output signal and the AC output signal, in the DC output signal of the specular reflection light detecting means, the DC output signal level on the positive side relative to the DC output signal level due to the reflected light from the normal portion of the surface to be inspected Or the negative side, the primary processing for discriminating dent defect and flaw system, and the secondary process for determining the continuity of coordinates on the inspection surface by extracting defect flaws from the flaw system by the time width comparator. With processing,
It is characterized by comprising a non-defective light spot, a defect determination processing means for discriminating non-defective scratches and defective scratches.

[0014]

According to the first and fourth aspects of the invention, in the primary processing for extracting the signal output direction and the signal time width with respect to the DC output signal level by the reflected light from the normal portion of the surface to be inspected, and the AC output signal, A defect and a non-defect are discriminated by combining a secondary process for discriminating the continuity of coordinates on the surface to be inspected where a signal exceeding a threshold value is generated.

According to the second and fifth aspects of the invention, when the surface to be inspected is a copper foil, the illumination light is laser flying spot light, and the incident angle to the surface to be inspected is 15 to 55.
The angle is within the range of 0 °, and the specular reflection light component is received within the light receiving angle range of 15 °.

According to the inventions of claims 3 and 6, of the DC output signal and the AC output signal, in the DC output signal of the specular reflection light detecting means, the DC output signal due to the reflected light from the normal portion of the surface to be inspected. Depending on whether it is the positive side or the negative side with respect to the level, the primary processing to discriminate the dent defect and the defect system, and the defect comparator to extract the defect defect from the defect system by the time width comparator, With the secondary processing to judge continuity,
A non-defective light spot, a non-defective scratch and a defective scratch are discriminated.

[0017]

Embodiments of the defect inspection method and the defect inspection apparatus of the present invention will be described below with reference to the drawings.

FIG. 1 shows the principle of defect detection. Figure 1 (a)
As shown in, the surface to be inspected of the inspection object 1 is irradiated with light to detect the difference in the distribution of reflected light amount. When there is no defect, the reflected light amount distribution 2 is shown by the solid line, and when there is a defect, the reflected light amount distribution 3 is shown by the dotted line. Although this uses reflected light, transmitted light may be used when the inspection target 1 is a transmissive body.

As a specific means for detecting the difference in the light amount distribution, as shown in FIG. 1B, a slit 4b formed in the central portion of the diffuser plate 4 by the mask of the light-shielding object 4a is used. The reflected (regularly transmitted) light component is transmitted, and this is transmitted to the photomultiplier tube 5 (photomultiplier tube: PM
As shown in FIG. 1 (c), the specular reflection light component is blocked by the mask of the light-shielding object 6a on the diffusion plate 6, and the diffuse reflection (transmission diffusion) light component is transmitted. It is measured by a multiplier 7 (photomultiplier tube: PMT), the change in the outputs of the photomultiplier tubes 5, 7 is detected, and the presence or absence of a difference from the normal part formation level is detected.

FIG. 2 shows an example of a laser flying spot type optical system. 2A is a plan view of the optical system, FIG.
(B) is a side view of the optical system, and the HeNe laser 10
The light from is applied to the polygon mirror 12 through the collimator lens 11, and the polygon mirror 12 is rotated to scan the light and collimate the light by the concave mirror 13 to irradiate the surface to be inspected of the inspection object 1. The difference in the distribution of the amount of reflected light from the surface to be inspected of the inspection object 1 is shown in FIG.
It is detected by the diffuse reflection light measurement of (c).

FIG. 2C is a plan view of another embodiment of the optical system, and FIG. 2D is a side view of another embodiment of the optical system.
The light from the HeNe laser 10 is applied to the polygon mirror 12 through the collimator condensing lens 14, is scanned by the rotation of the polygon mirror 12, and is directly irradiated on the surface to be inspected of the inspection object 1, and similarly, the surface of the inspection object 1 is irradiated. The difference in the distribution of the amount of reflected light from the inspection surface is shown in FIG.
It is detected by the diffuse reflection light measurement of (c).

FIG. 3 is a processing block diagram showing an embodiment of the defect inspection method and the defect inspection apparatus according to the present invention, and an output waveform diagram of each part.

The defect inspection apparatus irradiates the inspected surface of the inspected object 30 with illuminating light, and the reflected light from the inspected surface is received and photoelectrically converted to generate a DC output signal and an AC output signal. The detecting means 32 for obtaining, the primary processing for extracting the signal output direction and the signal time width with respect to the DC output signal level due to the reflected light from the normal portion of the surface to be inspected, and the AC output signal exceeding the threshold value are generated. A defect determination processing unit 33 that determines a defect and a non-defect by combining a secondary process that determines the continuity of coordinates on the surface to be inspected is provided. Here, the non-defect means that a signal change of a predetermined level or more occurs with respect to the PMT output level due to the reflected light from the normal portion of the surface to be inspected, but it is not regarded as a defect.
Further, there are types A and B in the defects. Class A is, for example, scratches, light spots, contact-type surface roughness meter jig marks, etc., whose surface glossiness is higher than that of the normal surface texture, and the signal level is normal on the surface to be inspected. It becomes brighter than the DC output level due to the reflected light from the section. In addition, class B is
The gloss of the surface is almost the same as that of the normal part, but it is concave or convex, for example, dents (concave), blister (convex), and the signal level from the normal part of the inspected surface. Appears in the direction of darkening relative to the DC output level due to reflected light.

The irradiation means 31 is provided with a light projecting portion 34, and
It is composed of an optical system as shown in.

The detecting means 32 includes a light receiving portion 35, and the PMT output is obtained from the light receiving portion 35. The waveform of the PMT output is shown in the output waveform diagram (a), and the defect signal b is generated with respect to the electric signal a reflecting the reflected light from the normal portion. An AC output signal is obtained from the PMT output by the AC filter 36 and is shown in the output waveform diagram (b). Also, a DC output signal is obtained by the DC filter 37,
It is shown in the output waveform diagram (c).

The defect determination processing means 33 includes an AC processing section 3
7, a grade processing unit 38, a DC processing unit 39, a grade processing unit 40, and a CPU 41. AC processing unit 37
Applies an AC comparator to the masked AC signal after passing through the AC filter 36, sends the signal applied to the AC comparator to the grade processing unit 40 after performing a rounding process. The DC processing unit 39 includes the DC filter 37.
After passing the masked DC signal, the DC comparator is applied, and the signal applied to the DC comparator is subjected to defect width determination processing, priority determination processing, width rounding processing,
Send to the grade processing unit 40.

Here, in the mask processing, as shown in FIG. 4, the object to be inspected 30 is scanned while being conveyed, and an AC signal of the PMT output thereof is obtained. However, the edge parts d1 and d2 and the position coordinates have regularity. An electrical mask is applied so as not to perform signal processing on a certain type A non-defective portion x1. Similar mask processing is performed on the DC signal output from the PMT.

In the width rounding process, as shown in FIG. 5, for example, in the width defect processing block of the fault signal of the AC signal,
There are s = 2 and m = 1 in the block, but the maximum value of "
m ″ is adopted as a defect signal. Similar width rounding processing is performed on the DC signal output from the PMT.

In the priority order determination process, as shown in FIG.
For example, the width of the defect signal processing block of the failure signal of the DC signal,
There are + es, + el, -es, and -el in one block, but + and-are processed independently.
Take in el preferentially.

The grade process is performed using the output of the comparator, and the comparator output used for the grade process is a fault signal of an AC signal and a fault signal of a DC signal.
As shown in FIG. 7, an example is shown in which the failure signals of the AC signals are grouped into n width scan defect processing blocks to be a unit. For the failure signal of the DC signal, see FIG.
Similar processing is performed only by replacing the AC signal of the above with the DC signal. The value thus unit-processed is multiplied by a weight constant and compared with the grade comparison value. The grade comparison value is a preset value, and if this value is exceeded,
It is a threshold value for determining s, m, l, etc.

Further, the CPU 41 performs pattern processing. In the pattern processing, as shown in FIG. 8, when a comparator output is generated over a unit continuous in the longitudinal direction, the continuity of the comparator output is determined, and a type A defect or non-defect is determined. When continuity is recognized, the comparator outputs of all blocks are captured.

When the inspection object 30 is, for example, a copper clad laminate, the illumination light is laser flying spot light,
The incident angle of the surface to be inspected to the copper foil is set in the range of 15 to 55 °, and the specular reflection light component is received within the light receiving angle range of 15 °.

Further, when the surface to be inspected is a copper foil, the irradiation means 31 makes the illumination light a laser flying spot light, and makes the incident angle to the surface to be inspected 15 to 55 °.
The detection means 32 includes a specular reflection light receiving section that receives a specular reflection light component within a light receiving angle range of 15 °, illuminates the surface to be inspected with illumination light, and photoelectrically converts the light reflected from the surface to be inspected. To obtain a DC output signal and an AC output signal. As described above, in the laser flying spot type optical system, the incident angle to the surface to be inspected is set in the range of 15 to 55 °, and the specular reflection light component is received within the light receiving angle range of 15 °. Among the above defects, the directions of the DC output signals of the dent system and the flaw light spot system can be separated to reduce the load of signal processing for the purpose of discrimination.

Of the DC output signal and the AC output signal, the defect judgment processing means 33 determines whether the DC output signal of the specular reflected light receiving portion is positive with respect to the DC output signal level of the reflected light from the normal portion of the surface to be inspected. Depending on whether it is the side or the negative side,
Non-defect light is detected by the primary process for discriminating between dent defect and defect system and the secondary process for extracting defect defect from the defect system by the time width comparator and judging the continuity of coordinates on the surface to be inspected. point,
A non-defective flaw and a defective scratch mark are discriminated.

Further, the illumination light is laser flying spot light, the incident angle on the surface to be inspected is in the range of 15 to 55 °, and the detecting means 32 detects the specular reflection light component in the light receiving angle range 1.
Only when the light is received within 5 °, the DC output signal is divided into the positive side and the negative side by setting the DC signal level due to the reflected light from the normal portion of the surface to be inspected to “0” as shown in FIG. It is possible to determine a scratch defect and a scratch defect. If the value is out of this limit, the dent defect will be difficult to distinguish because the DC output signal can be positive or negative.

FIG. 9 is a diagram showing the DC output level of the specularly reflected light receiving portion having a copper foil surface defect and no defect. The threshold CMP1 and the threshold CMP1 are set with respect to the DC output level of the specular reflection light receiving portion, and the defects of the class B (dent system) are
It can be seen that the DC output signal of the specular reflected light receiving section appears only on the positive side (dark direction). In addition, it can be seen that in the scratches, light spots, and measuring jig trace system of type A, the DC output signal of the specular reflection light receiving unit appears only on the negative side (brightening direction).
From the above, the dent system and the scratch, light spot, and measurement jig trace system are distinguished.

FIG. 10 is a scatter diagram showing the relationship between the DC output level of the specular reflection light receiving section and the time width. By determining whether it is wider or narrower than the predetermined signal time width T _B , it is possible to extract the defect scratch from the scratches of type A, the light spot, and the measurement jig trace system. The defect flaw is narrower than a predetermined signal time width, and a non-defect light spot, a scratch, or the like has a predetermined signal time width T _B.
Wider than.

FIG. 11 shows simulation signals A, B and C for defect and non-defect signal processing based on the propositions derived from FIGS. 9 and 10 and shows signals of respective parts in the processing block of the defect inspection apparatus. It is a thing. The signals s and m of the processor are output as waveforms corresponding to the s and m signal levels of the waveform of the signal after the AC filter.

In the logic A, when the signal after the DC filter is equal to or higher than the threshold value CMP2 (the positive side is larger than the formation level), it is a type B defect. Further, in the logic B, the signal after the DC filter is equal to or higher than the threshold value CMP1 (the negative side is larger than the formation level) and the predetermined time width T
_{It is B} or less, and a narrow signal N is output, which is a type A defect. Further, the logic C, the signal after the DC filter (the minus side larger than the texture level) threshold CMP1 or more and is the predetermined time width T _B above, a wide signal W
Are output, which are non-defects of type A, non-defects and defects of type A (wide and long scratches).

FIG. 12 is a flow chart of defective and non-defective signal processing. If the mask processing is performed in step a, the logic A is determined in step b, and the logic C is equal to or higher than the threshold value CMP2 (the positive side is larger than the formation level), it is a type B defect. Next, in step c, the logic B is determined, and if the signal after the DC filter is greater than or equal to the threshold value CMP1 (the negative side is larger than the formation level) and less than or equal to the predetermined time width T _{B in} the logic B. The narrow signal N is output, and there is a type A defect, and thus the primary processing is performed.

When the logic C is judged in step c, the signal after the direct current filter has a threshold value CMP1.
Above (the negative side is made larger than the formation level) and above the predetermined time width T _B , the wide signal W is output. Further, in step d, regarding the class A non-defects of logic C, non-defects and class A defects (wide and long scratches), step e
The secondary processing is carried out with the pattern processing, and the continuity of the unit is judged by the pattern processing. If there is no continuity of the unit, it is judged as a non-defect and non-defect of type A, and if there is continuity of the unit, a defect of type A. (Wide and long scratches).

In this way, it is possible to discriminate between defects and non-defects of the object to be inspected, and Table 1 shows an example in the case where tuning is performed so as to eliminate underaction as a result of applying the logics A, B, and C. .

[0043]

[Table 1] Equal: Good product is judged as good product Over: Good product is judged as defective product In Samples 16 and 17, in logic B judgment, threshold CMP1 or more and predetermined signal time width T _B
It becomes the following.

In the sample 24, in the logic B judgment, no signal is obtained up to the level of the threshold value CMP1.

Samples 1, 3, 5, 10, 11, 21, 21
In No. 22, since there are type A defects and non-defects, items 2 to 3 are divided into two stages.

The symbols .about. Indicate those satisfying the judgment conditions of the logics A to C, respectively.

Among those satisfying the condition of logic C, those having a scratch length of 10 mm or more are indicated by ◯.

The mask processing for judging non-defects as non-defects is shown by a circle.

Is the defect / non-defect determination result of each signal according to.

Is a non-defective / defective logic determination result for one sample.

It can be seen from Table 1 that all defective samples are judged to be defective, and non-defective products are judged to be defective on the safe side.

Therefore, according to this embodiment, in the direct current output signal obtained by irradiating the surface to be inspected with illumination light and photoelectrically converting the light from the surface to be measured, the direction of the output from the normal part formation level and the signal time. Defects and non-defects can be discriminated by combining the primary processing for extracting the width and the secondary processing for determining the continuity of the coordinates on the inspection surface where a signal exceeding a predetermined threshold value is generated.

As described above, it is of course possible to discriminate between defects and non-defects such as the surface inspection of a copper clad laminate, and the inspection and classification target has the same shape and optical characteristics without being caught only by these. If so, it goes without saying that it is applicable.

[0054]

As described above, the first and second aspects are provided.
The invention described in claim 4 or claim 5 makes it possible to discriminate between a defect having a signal change and a non-defect with respect to the normal part formation signal level, so that the discrimination level is brought close to the level of the artificial inspection. , Can increase reliability.

According to the third and sixth aspects of the present invention, in the DC output signal of the specular reflection light receiving section, the most frequent "dent defect" (signal level is , The surface appears darker than the normal formation level), and the surface glossiness increases more than the normal part formation, the light spot system (the signal level is brighter than the normal formation level) Direction)), the defect flaws are extracted at the output level and the comparator level with two time widths in the area where the surface gloss increases from the normal area texture, and the remaining scratches, light spots, and measurement jigs are extracted. As for the mark, it is possible to discriminate between defects and non-defects based on the continuity in the transport direction, and the discrimination level can be brought closer to the level of artificial inspection and the reliability can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing the principle of defect detection.

FIG. 2 is a diagram showing an example of a laser flying spot type optical system.

FIG. 3 is a processing block diagram showing an embodiment of a defect inspection method and a defect inspection apparatus, and an output waveform diagram of each part.

FIG. 4 is an explanatory diagram of mask processing.

FIG. 5 is an explanatory diagram of a width rounding process.

FIG. 6 is an explanatory diagram of priority order determination processing.

FIG. 7 is an explanatory diagram of unit processing.

FIG. 8 is an explanatory diagram of grade processing.

FIG. 9 is a diagram showing a DC output level of a specular reflection light receiving part having a copper foil surface defect and a non-defect.

FIG. 10 is a scatter diagram showing the relationship between the DC output level of the specular reflection light receiving section and the time width.

11 is a diagram showing a signal of each part in a processing block of a defect inspection apparatus, in which a simulation logic for defect / non-defect signal processing is created based on the proposition derived from FIGS. 9 and 10. FIG.

FIG. 12 is a flowchart of defective / non-defective signal processing.

[Explanation of symbols]

 30 inspected object 31 irradiation means 32 detection means 33 defect determination processing means

Claims (6)

[Claims] 1. A surface to be inspected is irradiated with illumination light, and light reflected from the surface to be inspected is received and photoelectrically converted to obtain a DC output signal and an AC output signal. Primary processing for extracting a signal output direction and a signal time width with respect to the DC output signal level by reflected light, and determining continuity of coordinates on a surface to be inspected in which a signal exceeding a threshold is generated in the AC output signal A defect inspection method, characterized in that a secondary process is combined to discriminate between a defect and a non-defect. 2. When the surface to be inspected is a copper foil, the illumination light is a laser flying spot light, the incident angle to the surface to be inspected is in the range of 15 to 55 °, and the specular reflection light component is the light receiving angle range. The defect inspection method according to claim 1, wherein the light is received within 15 °. 3. When the surface to be inspected is irradiated with illumination light and the surface to be inspected is a copper foil, the illumination light is laser flying spot light, and the incident angle to the surface to be inspected is in the range of 15 to 55 °. , The specular reflection light component is received within the reception angle range of 15 °,
The reflected light from the surface to be inspected is photoelectrically converted to obtain a DC output signal and an AC output signal, and among the DC output signal and the AC output signal, a DC output signal by reflected light from a normal portion of the surface to be inspected. Depending on whether it is the positive side or the negative side with respect to the level, the primary processing to discriminate the dent defect and the defect system, and the defect comparator to extract the defect defect from the defect system by the time width comparator, A defect inspection method characterized in that a non-defect light spot, a non-defect scratch, and a defect scratch are discriminated by a secondary process for judging continuity. 4. An irradiation means for irradiating the surface to be inspected with illumination light,
Detecting means for receiving the reflected light from the surface to be inspected and photoelectrically converting it to obtain a DC output signal and an AC output signal, and a signal output direction with respect to the DC output signal level by the reflected light from the normal portion of the surface to be inspected. Defects and non-defects are combined by combining the primary processing for extracting the signal time width and the secondary processing for determining the continuity of the coordinates on the surface to be inspected where a signal exceeding the threshold value is generated in the AC output signal. A defect inspection apparatus comprising: a defect determination processing unit for determining. 5. The illumination light is laser flying spot light, the incident angle on the surface to be inspected is in the range of 15 to 55 °, and the specularly reflected light component is received within the light receiving angle range of 15 °. The defect inspection apparatus according to claim 4. 6. Illuminating means for illuminating the laser light is a laser flying spot light, and an incident means for making an incident angle on the surface to be inspected within a range of 15 to 55 °; Detecting means for irradiating the surface to be inspected with the illumination light and photoelectrically converting the light reflected from the surface to be inspected to obtain a DC output signal and an AC output signal; and the DC output signal. Among the AC output signals, in the DC output signal of the specular reflection light detection means, depending on whether the DC output signal level due to the reflected light from the normal portion of the surface to be inspected is positive or negative, A primary process of discriminating between a system defect and a flaw system, and a defect flaw of the flaw system is extracted by a time width comparator to judge the continuity of coordinates on the inspection surface 2
A defect inspection apparatus comprising: a non-defect light spot, and a defect determination processing unit that determines a non-defect scratch and a defect scratch on the next process.