JPH1027379A - Optical disk for adjusting/inspecting optical pickup - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adjusting/inspecting optical disk capable of adjusting an optical pickup capable of optically information recording/reproducing two kinds of optical disks with different thickness of transparent substrates by a sheet of adjusting/inspecting optical disk with a simple structure. SOLUTION: The adjusted optical pickup 4 is able to obtain the state reproducing an information track 2 on an optical disk main body 1 through an auxiliary disk 3 and the transparent substrate 1a of the optical disk 1 and the state reproducing the information track 2 through only the transparent substrate 1a of the optical disk main body 1 without the intermediary of the auxiliary disk 3, and the optical pickup capable of optically information recording/ reproducing for two kinds of optical disks with different thickness of transparent substrates is adjusted/inspected only by minutely moving the reproducing position of the adjusting/inspecting optical disk without exchanging the adjusting/ inspecting optical disk.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk for adjustment and inspection in a manufacturing process of an optical pickup capable of optically recording and reproducing information on two types of optical disks having different thicknesses of a transparent substrate.

[0002]

2. Description of the Related Art Conventionally, as an optical disk for adjustment inspection in a manufacturing process of an optical pickup, a plurality of optical disks having the same structure as a general commercially available optical disk are used as required.

In the case of an optical pickup for DVD, a recording or reproducing function corresponding to both an optical disk for DVD having a substrate thickness of 0.6 mm and an optical disk for CD having a substrate thickness of 1.2 mm is required. In the manufacturing process, two kinds of optical disks for adjustment and inspection are required, one for DVD and one for CD. FIGS. 5A and 5B show a disk used for adjustment inspection in a conventional manufacturing process, where FIG. 5A shows an optical disk for DVD, and FIG.
Optical disk, DVD optical disk is information track 2
Are covered with a 0.6 mm thick transparent substrate 1a. C
The optical disk for D has an information track 2 covered with a transparent substrate 1b having a thickness of 1.2 mm.

[0004]

As described above, when two optical disks are used in the adjustment inspection process, it is necessary to divide the process into two or replace the disk in one process. When the process is divided into two, there are disadvantages that the equipment cost is high and the number of adjustment inspection man-hours is increased.

In the case of exchanging disks in one step, a method of changing the disk and a method of mounting the disks on two spindle motors in advance and moving each disk can be considered. In the former case, There is a disadvantage that the man-hour required for replacement increases and that the inclination accuracy of the disk for each replacement slightly changes. In the latter case, the use of two spindle motors increases the equipment cost and requires a long stroke. It has disadvantages such as an increase in the number of man-hours required, a decrease in disc tilt accuracy, and an increase in the size of equipment.

Further, as shown in FIG. 6, it is conceivable that the DVD optical disk 9 and the CD optical disk 10 are processed concentrically and bonded to another member 11 to be used as one disk. There are problems such as cost, distortion applied to the disk during processing, and eccentricity of the disk on the outer peripheral side.

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical disk for adjustment inspection which realizes the reduction in the size and cost of equipment, the reduction in man-hours, the improvement in adjustment accuracy, and the ease of manufacture, which are the problems.

[0008]

An optical disk for adjustment inspection according to the present invention is characterized in that an auxiliary disk having a smaller area than the optical disk main body is provided concentrically or substantially concentrically on a transparent base of the optical disk main body and fixed. Characteristically, according to the present invention, an optical pickup capable of optically recording and reproducing information on two types of optical disks having different thicknesses of the transparent substrate can be adjusted with a single adjustment inspection optical disk having a simple structure.

[0009]

An optical disk for adjusting and inspecting an optical pickup according to claim 1, wherein the transparent substrate of the optical disk main body has an information track on which a reflective film is formed covered by a transparent substrate for transmitting detection light of the optical pickup. An auxiliary disk made of a material that transmits the detection light of the optical pickup and having a smaller area than the optical disk main body is provided concentrically or substantially concentrically and fixed thereon.

According to this structure, the optical pickup to be adjusted is in a state of reproducing the information tracks of the optical disk main body through the auxiliary disk and the transparent base of the optical disk main body, and the optical disk is passed only through the transparent base of the optical disk main body without passing through the auxiliary disk. A state in which the information track of the main body is reproduced can be obtained.

According to a second aspect of the present invention, in the optical disk for adjustment inspection of an optical pickup according to the first aspect, the format of the information track of the optical disk body in the portion where the auxiliary disk is fixed is the same as that of the information track in the other portion of the optical disk body. It is characterized by being different from the format.

According to a third aspect of the present invention, there is provided an optical disk for adjusting and inspecting an optical pickup, wherein an auxiliary disk is provided at the center of the optical disk body and fixed. Hereinafter, embodiments of the present invention will be described with reference to FIGS.

(Embodiment 1) FIG. 1 shows (Embodiment 1).
2 shows an optical disk for adjustment inspection of FIG. Reference numeral 1 denotes an optical disk body, which is a DVD optical disk having a transparent substrate 1a having a thickness of 0.6 mm on one side. Reference numeral 2 denotes an information track of the optical disk main body 1, reference numeral 3 denotes a glass disk as an auxiliary disk, and a plate thickness of 0.6 m when the refractive index is the same as that of the optical disk main body.
m.

The glass disk 3 has a smaller diameter than the optical disk main body 1 and has a smaller area than the optical disk main body 1. The glass disk 3 is adhered concentrically or substantially concentrically to the center of the optical disk main body 1.

The operation of the optical disk for adjustment and inspection configured as described above will be described below. FIG. 2 shows D
This is a state in which the signal of the DVD format section of the optical disk for adjustment inspection shown in FIG. 1 is being reproduced by the VD optical pickup 4. Since the DVD optical pickup 4 needs to reproduce discs of two different formats, DVD and CD, the objective lens 5 has a thickness of the transparent substrate of 0.6.
It has two focal points, a DVD focal point 6 mm for the DVD and a CD focal point 7 for the 1.2 mm thick transparent substrate.

FIG. 2 shows a state in which the DVD optical pickup 4 is focused on the information track 2 of the optical disk main body 1. Since various adjustments in the manufacturing process of the DVD optical pickup are usually performed using a DVD disk, the adjustment of the DVD optical pickup 4 can be performed in the state of FIG.

After the adjustment, when inspecting the CD characteristics, the reproducing position of the disc is slightly moved as shown in FIG. The thickness becomes equivalently 1.2 mm, and reproduction can be performed with a CD spot.

At this time, it is difficult to reproduce a high frequency component because a signal having a small pit shape in the DVD format is reproduced at a spot for a CD. However, inspection items are limited to those of a DC component or a low frequency component of the signal. If it can be used enough.

Further, even when the adjustment is required again after the CD inspection, the DVD adjustment can be performed by slightly moving the reproduction position of the optical disk for adjustment inspection. The optical disk for adjustment inspection of the present embodiment is a normal DVD.
The optical disk 1 for use and the glass disk 3 are bonded together, but this bonding does not need to be optical bonding using a transparent UV adhesive or the like, and can be performed simply by bonding with a double-sided tape other than the signal reproducing portion. Base thickness 1.2mm
Can be realized, so that it can be created very easily.

As described above (Embodiment 1),
It is possible to perform an adjustment inspection of an optical pickup capable of optically recording and reproducing information on an optical disk having two types of substrate thicknesses by using only one adjustment inspection optical disk without replacing the adjustment inspection optical disk.

Specifically, the material of the transparent substrate 1a of the optical disk main body 1 is polycarbonate (plate thickness: 0.6 mm).
When a material having a refractive index of 1.47 is used as the glass disk 3 and the wavelength of the light source of the optical pickup 4 is 650 nm in this case, the optimal thickness of the glass disk 3 is 0.61 mm. there were.

(Embodiment 2) FIG. 4 shows (Embodiment 2)
1 shows the structure of an optical disk for adjustment inspection of FIG. In FIG.
The information track portion 8 to which the glass disk 3 is attached is the same as the information track of the CD format, and the others are the same as those shown in FIG. 1 (Embodiment 1).

In the case of the first embodiment, the items are limited to the DC type at the time of adjusting and inspecting the CD. However, in the second embodiment, the bonded portion of the glass disk 3 has a base thickness of 1. Since the information track 8 has a CD format of 2 mm, the adjustment test of the CD can be performed under exactly the same conditions as a normal optical disc for a CD.

[0024]

As described above, according to the present invention, the optical pickup is placed on the transparent substrate of the optical disk body in which the information track on which the reflection film is formed is covered with the transparent substrate transmitting the detection light of the optical pickup. An auxiliary disk having a smaller area than the optical disk body with a material that transmits the detection light of
The optical pickup that is adjusted is provided in a concentric or substantially concentric manner and is fixed. The information track of the optical disc main body can be reproduced through the base alone, and the thickness of the transparent base is different only by slightly moving the playback position of the adjustment test optical disc without changing the adjustment test optical disc. An adjustment inspection of an optical pickup capable of optically recording and reproducing information on two types of optical disks can be performed.

Therefore, the advantageous effects of reducing the size and cost of the adjustment inspection equipment of the optical pickup, reducing the number of adjustment inspection man-hours, and improving the adjustment accuracy can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an optical disk for adjustment inspection according to a first embodiment.

FIG. 2 is a diagram showing a reproduction state of a DVD signal of an optical pickup using the optical disk for adjustment inspection according to the embodiment.

FIG. 3 is a diagram showing a reproduction state at a CD spot of the optical pickup using the optical disk for adjustment inspection according to the embodiment;

FIG. 4 is a cross-sectional view of the optical disk for adjustment inspection according to the second embodiment.

FIG. 5 is a sectional view of two conventional optical disks for adjustment inspection.

FIG. 6 is a cross-sectional view of another optical disk for adjustment inspection for explaining a problem to be solved by the invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical disk main body 1a Transparent base of optical disk main body 1 2 Information track of optical disk main body 3 Glass disk [auxiliary disk] 4 Optical pickup 5 Objective lens 6 Focus for DVD 7 Focus for CD 8 Information track of CD format

Claims (3)

[Claims] 1. An optical disk made of a material that transmits the detection light of the optical pickup, on the transparent substrate of the optical disk body, wherein the information track on which the reflection film is formed is covered with a transparent substrate that transmits the detection light of the optical pickup. An optical pickup for adjusting and inspecting an optical pickup in which an auxiliary disc having a smaller area than the main body is provided concentrically or substantially concentrically and fixed. 2. The optical pickup according to claim 1, wherein the format of the information track of the optical disk body at the portion where the auxiliary disk is fixed is different from the format of the information track of the other portion of the optical disk body. optical disk. 3. The optical disk for adjustment inspection of an optical pickup according to claim 1, wherein an auxiliary disk is provided and fixed at the center of the optical disk body.