JPS62295234A - Test disk for optical disk - Google Patents

Abstract

PURPOSE:To make flaw simulation approximate to actual flaws possible and make measurement of playability of a reproducing optical disk player possible by providing plural printed films of equal line width, length and depth in the direction at right angles to radial direction and nearly parallel to track direction on the reading face of a disk. CONSTITUTION:Plural printed films of equal line width, length and depth are provided in the direction at right angles to radial direction and nearly parallel to track direction on the reading face of a disk. For instance, three printed films 9 of line width 50mum, length 2mm, depth 100mum are attached in the direction at right angles to radial direction and nearly parallel to track direction to form the first flaw simulation 10. Thus, by providing three printed films 9 nearly parallel to track direction, it is possible to obtain omission information nearly proportional to the length of the flaw when reproducing digital signals, and as omitted parts and normal parts exist alternately, for time of several tens of seconds, the first flaw simulation 10 is closely approximate to actual flaw.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention Industrial Application Field The present invention records digital signals such as video discs, digital audio discs (eg compact discs), still images and document files.

This relates to test discs for playable or erasable optical discs. Conventional technology Generally speaking, optical discs are considered promising as information media due to their extremely high information density, high S/N ratio, and low noise. It has been commercialized as a video disc and a digital audio disc, and research and development has been conducted in recent years as an optical disc for recording and reproducing digital signals.

FIG. 6 shows an outline of a compact disc, which is a conventional general digital audio disc.

In this method, a PCM-converted digital signal is recorded in the form of a bit string on a resin substrate and reproduced by a semiconductor laser beam.

In FIG. 6, 1 is a disk, 2 is a resin substrate, 3 is a bit string-shaped gage digital signal section provided on the resin substrate 2,
4 is a reflective film formed on its surface, 5 is a protective film coated on the reflective film 4, 6 is a label printing film provided on the protective film 6, 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 is necessary for disc identification.

For conventional optical discs, if there is a defect due to a scratch on the disc reading surface, the optical disc player will not be able to properly reproduce the digital signal, and playback abnormalities such as track jumps and noise may occur. be. It is extremely difficult to simulate these scratches, and there were no good optical disc test discs. However, as a conventional example, scratches were attached in a direction perpendicular to the track, and the scratches were attached over a certain width. FIG. 3 shows a plan view of a conventional optical disk test disk. 1 is a disk, and 8 indicates a scratch made in a direction perpendicular to the track direction.

Problems to be Solved by the Invention However, in the above configuration, the scratches are attached in a direction perpendicular to the track direction of the disk, and the scratches are completely formed between a certain track length, so the area where the laser beam is missing is large. This method had problems such as being excessively large and not simulating actual scratches.

In view of the above-mentioned problems, the present invention provides an optical disc test disc that simulates scratches that occur during actual handling.

Means for Solving the Problems In order to solve the above problems, the test disk of the optical disk of the present invention has lines of each printed film on the disk reading surface in a direction perpendicular to the radial direction and substantially parallel to the track direction. By providing a plurality of printed films with the same width, length, and depth, a scratched disk is simulated.

According to the above-described configuration, the present invention prints a plurality of printed films on the disk reading surface in a direction perpendicular to the radial direction and substantially parallel to the track direction, each having the same line width, length, and depth. By providing this and simulating actual scratches, it is possible to reliably obtain an optical disc test disc for measuring the playability of an optical disc player.

EXAMPLE Hereinafter, a test disk of an optical disk according to an example of the present invention will be explained with reference to the drawings.

FIG. 1 shows a plan view of a test disc of an optical disc in a first embodiment of the present invention.

In FIG. 1, a line has a width of 60 μm and a length of 2 fl in a direction perpendicular to the radial direction and approximately parallel to the track direction.

A printed film 9 having a depth of 100 μm is deposited to form a first scratch and stain repair 10. The provision of three printed films 9 substantially parallel to the track direction in this way makes it possible to obtain missing information approximately proportional to the length of the scratch when reproducing a digital signal. Since missing portions and normal portions alternate over a period of several tens of seconds, the first flaw simulation 10 closely approximates the actual flaw.

FIG. 4 shows an RF waveform representing the electrical characteristics of the first scratch simulation 10 as seen from the playback player. Here, Fig. 4a shows R when playing an actual scratched disc.
FIG. 4 shows an RF waveform when the first flaw simulation 10, which is an embodiment of the present invention, is reproduced.

For reference, FIG. 4C shows an RF waveform when the conventional example of the scratched disc shown in FIG. 3 is played back. In this way, it is clear from the instantaneous characteristics that the first flaw simulation 10 closely approximates the actual flaw.

A second embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a plan view of a test disc of an optical disc showing a second embodiment of the present invention. Second
In the figure, in the direction perpendicular to the radial direction of the optical disc,
Each line has a width of 60 μm and a depth of 1 approximately parallel to the track direction.
Three sets of three printed films with a pitch of 300 μm and a pitch of 300 μm were provided, and the lengths were 5 m, 3 am, and 2 am, respectively.
ml and the first wound simulation 10. Second
Wound simulation 11. This is a third flaw simulation 12. According to this, by providing a plurality of scratch simulations within one optical disc, it is possible to make the disc optimal as a test disc for measuring the playability of a reproduction optical disc player.

Note that it is also possible to obtain a test disk having the same effect as this by keeping the line width, depth, and length the same and changing only the pitch of the printed film.

Effects of the Invention As described above, the present invention prints a plurality of printed films on the disk reading surface in a direction perpendicular to the radial direction and substantially parallel to the track direction, each having the same line width, length, and depth. By providing this, it is possible to simulate scratches that approximate actual scratches, and it is possible to measure the playability of a reproduction optical disc player. Furthermore, by freely changing the pitch and length of the printed film to form a plurality of scratch simulations within one disc, the present invention provides a highly reliable optical disc test disc for measuring the playability of a reproducing optical disc player. be able to.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an optical disk test disk according to a first embodiment of the present invention, FIG. 2 is a plan view of an optical disk test disk according to a second embodiment of the present invention, and FIG. 3 is a plan view of a conventional optical disk test disk. FIG. 4 is a plan view of the test disc, and FIG. 4 shows the RF waveform of electrical characteristics in a reproducing optical disc player. FIG. 4a is an RF waveform diagram of an actual scratched disc, and FIG. FIG. 4C is an RF waveform diagram of a test disc of an optical disc, and FIGS. 5A and 5B are RF waveform diagrams of a conventional test disc. C is a plan view, a sectional view, and an enlarged view of essential parts of a compact disc, which is a type of optical disc. 1...disc, 9...printing film, 10
・Mountain... 1st wound simulation, 11...Mountain 2nd
scratch simulation, 12...Third scratch simulation. Figure 1 Figure 2 12-years old, 7t9

Claims (3)

[Claims] (1) A plurality of printed films are provided on the disk reading surface in a direction perpendicular to the radial direction and substantially parallel to the track direction, each having the same line width, length, and depth. Optical disc test disc. (2) The line width of each printed film is 20 to 100 μm, and the length is 1 to 100 μm.
10mm, depth 20-500μm, pitch 50-5
2. The test disk for an optical disk according to claim 1, wherein the test disk has a diameter of 0.00 μm. (3) On one disk reading surface, the line width and depth of each printed film in the direction perpendicular to the radial direction and almost parallel to the track direction were the same, and only the pitch or length was changed sequentially. A test disc for an optical disc characterized by having a scratch simulation shape formed by a plurality of printed films.