JPS62293532A - Test disk for optical disk and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a test disk with high quality by adhering a metallic foil with a prescribed thickness to a clamping region so as to obtain a desired warp on a signal region. CONSTITUTION:The metallic foil 10 made of stainless steel or bronze is adhered to a clamping region 9 at the read face side 8 of a disk 1 by a thermosetting or cyanobond group adhesives. The thickness of the foil 10 is decided by a desired warp and the warp on the signal region with 0.3-0.5mm gives its effect on the tracing performance of a player, then the thickness of the foil is selected to be 0.05-0.15mm to make the warp test disk. In placing the test disk on a turntable 12 of a spindle motor 11, the table 12 and the foil 10 are contacted and the thickness of the foil 10 determines the warp in the reproducing region signal of the optical pickup 13 proportionally.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a test disk for optical disks capable of recording, reproducing or erasing digital signals such as video disks, digital audio disks (e.g. compact disks), still images, document files, and the like. This relates to a manufacturing method.

Conventional technology In general, optical discs are considered promising as information media due to their extremely high information density, high S/N ratio, and low noise, and have been commercialized as video discs and digital audio discs, which record digital signals. In recent years, research and development has also been conducted on optical discs for playback.

FIG. 3 shows an overview of a compact disc, which is a conventional general digital audio disc.

In this method, a POM-converted digital signal is recorded in a pit array on a resin substrate and reproduced by a semiconductor laser.

In FIG. 3, 1 is a disk, 2 is a resin substrate, 3 is a digital signal part in the form of a pit row carved on the resin substrate 2, and 4
5 is a reflective film formed on the surface thereof, 5 is a protective film coated on the reflective film 4, 6 is a label printing film provided on the protective film 5, and 7 is a semiconductor laser beam for reproduction.

The reflective film 4 is necessary for reproducing digital signals, the protective film 5 is necessary for protecting the reflective film, and the label printing film 6 is necessary for identifying the disc.

Regarding conventional optical discs, there are standards regarding the shape of the disc, such as the amount of recoil and surface runout, and generally speaking, the smaller these values are, the better the disc is.

However, due to changes in temperature, humidity, etc. over time, and the environment, warping and surface runout may change, and if they become extremely large, it may not be possible to reproduce them properly.

Conventionally, there has been no test disk for optical disks in which the value of surface runout has been artificially controlled, and the amount of surface runout of a ready-made disk has simply been measured and used as a test disk.

Problems to be Solved by the Invention However, with the above configuration, it is not possible to arbitrarily control the amount of surface runout of an optical disc, so it is not applicable to checking the tracing performance of a playback player or measures for playability. There were problems such as the inability to do so.

In view of the above-mentioned problems, the present invention provides a highly reliable optical disk test disk in which the amount of surface runout is controlled, and a manufacturing method capable of stably manufacturing the same.

Means for Solving the Problems In order to solve the above problems, the test disk of the optical disk of the present invention has a metal plate having a thickness of 0.05 m to 0.15 rrrm in the clamping area on the reading surface side of the disk. It is equipped with foil.

Effect of the present invention In accordance with the above-described configuration, a metal foil having a thickness of 0.05 mm to 0.15 mm is formed by adhesion in the clamping area of the disk to obtain a desired amount of surface runout in the signal area. As a result, a highly reliable optical disc test disc can be produced.

EXAMPLE Hereinafter, a test disk for an optical disk according to an embodiment of the present invention and a method for manufacturing the same will be explained with reference to the drawings. FIGS. 1(a) and 1(b) show a plan view and a sectional view of a test disc of an optical disc in an embodiment of the present invention. A metal foil 10 is provided in a clamping area 9 on the reading side 8 of the disc 1 . metal foil 10
The thickness may be changed depending on the desired surface runout value. Normally, the disk runout amount is 0.3rt in the signal area.
Since the tracing performance of the reproducing player starts to be affected at around rtn~0.5, the metal foil is set at 0.05~0.15.
By selecting mm, a test disk with surface runout of this level can be manufactured.

It is desirable to bond the metal foil using a thermosetting or cyan bond adhesive, and stainless steel (SUS), brass, etc. are effective metals. Figure 2 shows how to use this test disk. As shown, a test disk is installed on the turntable 12 on the spindle motor 11, and the turntable 12 and the metal foil 10 are connected to each other.
The thickness of the metal foil is proportional to the thickness of the optical pickup 13
The amount of surface runout in the reproduction area signal portion is determined.

Effects of the Invention As described above, the present invention provides a clamping area on the reading surface side of a disc containing information with a thickness of 0.05 mm to 15 mm.
By providing the metal foil, it is possible to obtain a desired amount of surface runout in the signal region, so a highly reliable optical disk test disk with a constant amount of surface runout can be manufactured at a low cost.

[Brief explanation of the drawing]

FIGS. 1(2L) and 1(b) are a plan view, a cross-sectional view, and a second
The figure is a sectional view of an optical disk test disk according to an embodiment of the present invention in a mounted state in a playback player, and FIG.
a), (b), and (C) are a plan view, a cross-sectional view, and an enlarged view of essential parts, respectively, of a digital audio disc, which is a type of optical disc. 1... Disc, 8... Disk reading surface side, 9... Clamping area, 10...
...Metal foil. Name of agent: Patent attorney Toshio Nakao and one other person L-
-Task 2-Group k IO--・Zenhan attack 13゛°-length, ゛1quat 71 Fig. 3

Claims (2)

[Claims] (1) A metal foil with a thickness of 0.05 mm to 0.15 mm is provided in the clamping area on the reading surface side of the disk that contains information such as digital signals in the form of pit rows or guide grooves. Optical disc test disc. (2) A metal foil with a thickness of 0.05 mm to 0.15 mm is formed by adhesive on the clamping area on the reading surface side of the disc containing information, and a desired amount of surface runout is obtained in the signal area. A method for manufacturing a characteristic optical disc test disc.