JP3154074B2 - Optical disk inspection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[Table of Contents] The present invention will be described in the following order. Industrial application Conventional technology (FIG. 4) Problems to be solved by the invention (FIG. 4) Means for solving the problems (FIGS. 1 to 3) Operation (FIGS. 1 to 3) Example (FIG. 1) 3) Effect of the invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk inspection apparatus, and can be applied to, for example, an apparatus for inspecting a disk surface for defects during manufacturing of a compact disk.

[0003]

2. Description of the Related Art Conventionally, when manufacturing a compact disk, it is necessary to determine whether or not the finished compact disk can be shipped as a product. For this reason, an optical disk surface defect inspection machine (hereinafter referred to as an optical disk inspection) is required. Machine). This optical disk inspection machine inspects an optical disk by scanning the surface of the compact disk with a laser beam and focusing mainly on scratches and polarization defects on the surface of the optical disk.

As shown in FIG. 4, in an inspection process using the optical disk inspection machine 1, a compact disk 2 to be inspected is loaded into the optical disk inspection machine 1, and as a result, the optical disk inspection machine 1 The disc 2 is inspected for the presence of scratches, polarization defects, and the like, and the compact disc 2 is classified into an A product, a B product, or a C product based on the inspection result.

[0005] Product A is a case where the compact disk 2 has no scratches or polarization defects, and is sent to the shipping process 3 as a good product.
Conversely, the C product is a case where a polarization defect exists in the compact disk 2 and is excluded as a defective product. In addition, the product B is a case where only a scratch is present on the compact disk 2 and is sent to the visual inspection step 4.

In the visual inspection step 4, the compact disk 2
A human inspects the surface of the sample visually to determine whether it is good or defective according to the degree of the scratch. As a result, the compact disk 2 determined to be good is sent to the shipping process 3 in the same manner as the product A, and the compact disk 2 determined to be defective is replaced by C
Excluded as well as goods.

[0007]

However, in the above-described inspection process, the compact disk 2 determined to be a B-product by the optical disk inspection machine 1 is visually inspected in the visual inspection process 4, so that it has experience and skill. In addition to the necessity of humans, there is a problem that the inspection time becomes longer by human judgment.

In order to solve this problem, it is considered that the optical disk inspection machine 1 itself should judge whether the compact disk 2 classified as a product B based on only the scratches is a good product or a defective product. Many parameters have to be set or adjusted for the determination, which is difficult to realize.

The present invention has been made in view of the above points, and it is an object of the present invention to propose an optical disk inspection apparatus which can automate an optical disk inspection process with a simple configuration.

[0010]

According to a first aspect of the present invention, a loaded optical disc 2 is optically inspected, and as a result of the inspection, whether the optical disc 2 is a good product (A product) or not. An optical disc inspection machine 11 for outputting a defective product (C product) or an optical disc 2 only for scratches (B product); and an optical disc 2 only for scratches detected by the optical disc inspection machine 11 (B product) ), The optical disk inspection information OPT of the optical disk inspection machine 11 is input, and the teacher instructs the disk inspection information OPT of the optical disk 2 having only the scratches (B product) and the judgment of good or defective (NG / OK). Based on the learning repeated as data, the optical disk 2 (B
And a neural network 12 for judging whether the product is a good product (OK) or a defective product (NG).

In the second invention, the optical disk inspection device 11 scans the surface of the optical disk 2 with the laser beam L emitted from the laser light source 20, and the zero-order light L0 reflected by the optical disk 2 The disk inspection information OPT is generated based on the P-wave component, the S-wave component, and the primary light L1 reflected by the optical disk 2.

[0012]

The optical disk 2 loaded by the optical disk inspection machine 11 is optically inspected, and as a result of the inspection, the optical disk 2 is inspected.
Outputs the non-defective (A product), the defective product (C product), or the optical disc 2 with only the scratch (B product), and the disc inspection information OPT of the optical disc 2 with only the scratch and the non-defective product (B product). An optical disk 2 (B
The optical disk inspection information OPT of the optical disk inspection machine 11 is input for the optical disk 2 and the optical disk 2 (B
The inspection process of the optical disk 2 can be automated with a simple configuration by judging whether the product is a good product (OK) or a defective product (NG).

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

FIG. 1 in which parts corresponding to those in FIG.
Numeral 10 denotes an optical disk inspection apparatus according to the present invention as a whole, in which a compact disk 2 to be inspected is loaded on an optical disk inspection machine 11, and as a result, the optical disk inspection machine 11 Inspect for defects.

In this embodiment, as in the prior art, the optical disk inspection machine 11 classifies the compact disk 2 into A, B or C according to the inspection result. It is turned around and conversely, the product C is excluded as a defective product. In the case of this embodiment, the product B is the neural network 1
Tested again at 2.

This neural network 12 is shown in FIG.
As shown in the figure, the optical disk inspection machine 11 classifies the compact disk 2 as a product B into the optical disk inspection information OPT and the OK / NG determination information OK / NG as the result of the visual inspection performed by the visual inspection step 4 as to whether the product is good or defective. Is input as educational data, and learning on the educational data is repeated.

After that, the neural network 12
Is the optical disk inspection information O on the compact disk 2 classified by the optical disk inspection machine 11 as a B product.
Based on the PT, a judgment similar to the visual check by a skilled person is automatically executed, and it is judged whether the compact disk 2 classified as a B product can be shipped as a good product or cannot be shipped as a defective product.

In the case of this embodiment, the optical disk inspection device 11 is configured as shown in FIG. 3, and a laser beam L emitted from a laser light source 20 is applied to a first polarizing beam splitter (PBS) 21. And is converted into a linearly polarized laser beam. Subsequently, this laser light passes through the quarter-wave plate 22 to become circularly polarized laser light, which is condensed by the objective lens 23 and irradiates the compact disk 2. As a result, the reflected light reflected by the compact disk 2 is split into a zero-order light beam L0 that is regularly reflected and a primary light beam L1 that is reflected by a pit.

Of these, the zero-order light beam L0 is
3, the light is condensed by the condensing lens 24, and is split into a P-wave component and an S-wave component by the second polarizing beam splitter 25.
The primary light beam L1 is incident on the first and second zero-order optical photodiodes 26 and 27, respectively, and is focused on the primary light photodiode 28 disposed around the objective lens 23.

First and second zero-order optical photodiodes 2
The light receiving outputs PA and PB of 6 and 27 are input to a first addition circuit 29 and a subtraction circuit 30, respectively, and the resulting first addition signal PA + PB is converted into a feature extraction processing calculation circuit 31, a second addition circuit 32 , The first and second division circuits 33 and 34, and the subtraction signal PA-PB obtained from the subtraction circuit 30 is input to the second division circuit 34.

The received light output P1 of the primary optical photodiode 28 is input to a feature extraction processing calculation circuit 31, a second addition circuit 32, and a first division circuit 33. The second addition circuit 32 outputs the first addition signal PA of the first addition circuit 29.
+ PB and the light receiving output P1 of the primary optical photodiode 28
, And the resulting second addition signal PA + PB
+ P1 is input to the feature extraction processing calculation circuit 31.

The first dividing circuit 33 converts the light receiving output P1 of the primary optical photodiode 28 into a first addition signal PA + P.
B and the resulting division signal P1 / PA + P
B is input to the feature extraction processing calculation circuit 31, and the second division circuit 34 divides the subtraction signal PA-PB by the first addition signal PA + PB, and obtains the resulting division signal PA
−PB / PA + PB is input to the feature extraction processing calculation circuit 31.

The feature extraction processing circuit 31 receives a first addition signal PA + PB or 1
Next light receiving output P1, second addition signal PA + PB + P
1, first and second division signals P1 / PA + PB and P
The defect of the compact disk 2 is determined based on A-PB / PA + PB.

The feature extraction processing calculation circuit 31 has a first output consisting of the light receiving output of the zero-order light per one round because the compact disk 2 has scratches, foreign matter, cold sludge, dirt, black spots, pinholes and the like. If the sum signal PA + PB continuously exceeds the threshold value at a predetermined number or more points, the reflectivity falls, so that the product is classified as a B product or a C product according to the threshold value and output.

The feature extraction processing calculation circuit 31 indicates that a pit drop due to improper transfer or a pit crush due to oil is present on the compact disk 2, and the received light output P1 of the primary light per one round is a predetermined threshold value. If it exceeds, it is classified as a B product or a C product according to the threshold value as a pit defect and is output.

Further, the feature extraction processing calculation circuit 31 calculates that the absolute value of the difference / sum of the light-receiving outputs PA and PB of the P-wave and S-wave of the 0th-order light when cold, weld, and peeling unevenness exist on the compact disk 2 Exceeds a predetermined threshold value, it is classified as a polarization product as a C product and is output.

In the case of this embodiment, the feature extraction processing calculation circuit 31 outputs the classification result as to whether the compact disk 2 is an A product, a B product, or a C product as well as the classification result as B In the case of a product, the first addition signal PA + PB, which is the light receiving output of the zero-order light, the light receiving output P1, of the primary light
The second addition signal PA + PB + P1, the first and second division signals P1 / PA + PB, and PA-PB / PA + PB are sent to the network 12 as optical disk inspection information OPT.

In the above-described configuration, the process of inspecting the compact disk 2 by the optical disk inspection apparatus 10 only requires loading the compact disk 2 to be inspected into the optical disk inspection machine 11. In this way, according to the inspection result of the optical disk inspection machine 11, the compact disk 2 of the product A is sent to the shipping process 3 as a non-defective product,
Conversely, the C product is excluded as a defective product.

The B product is judged to be non-defective or non-defective by using the optical disk inspection information OPT input at the same time on the basis of the learning result in the neural network 12. It will be rejected if it is defective.

In this way, the optical disk inspection device 1
In the case of 0, the compact disk 2 is automatically inspected without going through a manual inspection process or the like, and it can be determined whether the compact disk 2 should be sent to the shipping process as a good product or excluded as a defective product. Can be significantly shortened, and since a skilled person is not required for the inspection, usability can be significantly improved.

According to the above configuration, the optical disk inspection machine 1
The compact disc 2 loaded in 1 is optically inspected, and as a result of the inspection, the compact disc 2 is output as a good product, a defective product, or a compact disc 2 having only scratches, and the disc of the compact disc 2 having only scratches is outputted. Inspection information OPT and judgment of OK / NG
The optical disk inspection information OP of the optical disk inspection machine 11 for the scratch-only compact disk 2
By inputting T and judging whether the compact disc 2 having only scratches is good or defective, it is possible to realize the optical disc inspection apparatus 10 that can automate the inspection process of the compact disc 2 with a simple configuration. .

In the above-mentioned embodiment, the present invention is applied to the inspection of a compact disk in the manufacturing process of the compact disk. However, the present invention is not limited to this, and other optical disks such as a video laser disk and a magneto-optical disk may be used. It is suitable for wide application to an optical disk inspection device for inspection.

[0033]

As described above, according to the present invention, an optical disk loaded by an optical disk inspection machine is optically inspected, and as a result of the inspection, the optical disk is determined to be a non-defective product, a defective product, or a light having only scratches. In addition to outputting the information on the disc, the optical disc of the optical disc inspection machine is used for the neural network that has repeatedly learned the disc inspection information of the optical disc with only scratches and the judgment of good or defective as teacher data as teacher data. Optical disk inspection device that can automate the optical disk inspection process with a simple configuration by inputting basic disk inspection information and determining whether an optical disk with only scratches is good or defective it can.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of an optical disk inspection apparatus according to the present invention.

FIG. 2 is a block diagram for explaining learning of a neural network in the optical disk inspection device of FIG. 1;

FIG. 3 is a block diagram showing a configuration of an optical disk inspection machine in the optical disk inspection device of FIG.

FIG. 4 is a block diagram showing an inspection process by a conventional optical disk inspection machine.

[Explanation of symbols]

1, 11 optical disc inspection machine, 2 compact disk, 3 shipping process, 4 visual inspection process, 12
Neural network, 20 laser light source, 2
1, 25 ... PBS, 22 ... 1/4 wavelength plate, 23, 2
4. Lens, 26, 27, 28 Photodiode, 29, 32 Addition circuit, 30 Subtraction circuit, 31
... Feature extraction processing calculation circuit, 33, 34... Division circuit.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01N 21/84-21/958 G01B 11/00-11/30 G11B 7/26

Claims (2)

(57) [Claims] 1. The optical disk loaded is optically inspected.
The optical disk inspection machine that outputs whether the optical disk is a good product, a defective product, or an optical disk with only a scratch as the inspection result, and the optical disk with only the scratch detected by the optical disk inspection machine, are as described above. Optical disk inspection information of the optical disk inspection machine is input, and based on the disk inspection information of the optical disk with only the scratches and the learning in which the judgment as to whether the optical disk is good or defective is repeated as teacher data, only the scratches are determined. An optical disk inspection apparatus, comprising: a network for determining whether an optical disk is good or defective. 2. The optical disk inspection apparatus scans a surface of the optical disk with a laser beam emitted from a laser light source, and detects a P-wave component, an S-wave component, and a 0-order light reflected by the optical disk. 2. The optical disk inspection apparatus according to claim 1, wherein the disk inspection information is generated based on primary light reflected by the optical disk.