JPH0443814Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] The present invention is an optical disk inspection device that measures various physical characteristics of optical disks, such as reflectance and transmittance of laser light, or plate thickness. This invention relates to the improvement of reference plates used in the calibration of measurement systems.

[Conventional technology]

Generally, in an optical disk inspection apparatus, the measurement system is calibrated before measuring various characteristics of the optical disk. There are various methods for this calibration, but calibrating the entire measurement system, including the detector and electric circuit, can be done at once by using a standard sample with known values. , convenient.

[Problem that the invention attempts to solve]

However, in such a calibration method, in order to obtain a calibration curve by interpolating from several measurement points,
Prepare several types of standard samples and place these standard samples one after another at the top of the optical head (laser beam irradiation position).
The standard sample must be set accurately, making it difficult to replace the standard sample.

The present invention aims to eliminate the above-mentioned drawbacks of the conventional device and to realize a reference plate for calibrating an optical disk inspection device with a simple structure, which allows multiple standard samples to be set accurately on the top of the optical head in sequence. This is the purpose.

[Means for solving problems]

The reference plate for calibrating optical disk inspection equipment of this invention is
A plurality of standard sample pieces priced at a predetermined reference value and a clamp portion that is commonly clamped by the clamping mechanism of the optical disk are arranged on the same circumference, and the plurality of standard sample pieces are arranged on the same circumference. and a substrate part for holding a standard sample piece so that the position of the reflective film surface or the transmitting film surface and the height from the clamp surface match the recording film surface of a normal optical disk clamped by the clamp mechanism. This is how it was done.

[Effect]

In this way, by arranging multiple standard sample pieces on the same circumference of the substrate and providing a clamp similar to an optical disk on this substrate, multiple standard sample pieces can be placed in a special jig. It can be clamped by the same clamping mechanism as the optical disk without using any other equipment, and any standard sample piece can be set on the top of the optical head simply by rotating the substrate part. Furthermore, if a plurality of standard sample pieces are held so that the position of the reflective film surface or the transmitting film surface and the height from the clamp surface match the recording film surface of a normal optical disk clamped by the clamp mechanism, each The standard sample piece is now always held at the same height as the optical disk, making it possible to perform calibration under conditions closer to actual measurement conditions. Furthermore, since the area of each standard sample piece is small, it has excellent uniformity.

〔Example〕

Hereinafter, the reference plate for calibrating an optical disk inspection device of the present invention will be explained using the drawings.

FIG. 1 is a plan view showing an embodiment of a reference plate for calibrating an optical disk inspection apparatus according to the present invention, and FIG. 2 is a sectional view thereof. In the figure, S0 to S11 are standard sample pieces priced at predetermined reference values, 1 is a substrate portion that holds the standard sample pieces S0 to S11 on the same circumference, and 2 is provided at the center of substrate portion 1. The clamp section 21 is a clamp surface that comes into contact with a turntable that rotates the optical disk in the clamp section 2. The standard sample pieces S0 to S11 are formed of, for example, a glass substrate, and a reflective film or a transparent film 3 is adhered to one surface. Also, if this reference plate is for reflectance or transmittance,
The plate thickness t is selected to be equal to that of a normal optical disk, and the value corresponding to the plate thickness is determined according to the price. Further, as shown in the figure, the substrate part 1 is arranged with the standard sample pieces S0 to S11 with their reflective film surface or transmitting film surface 3 facing upward, and the height of the film surface from the clamp surface 21 is normal. It is held so that the height of the recording film surface matches the height of the optical disc when clamped. For example, if the optical disk is of a type in which the substrate portion is directly clamped, the height of the recording film surface is equal to the thickness of the disk, so the standard sample pieces S0 to S11 have their bottom surfaces as shown in the figure. It is held in alignment with the clamping surface 21. In addition, if the optical disk has a hub for clamping, standard sample pieces S0~
The height of S11 is also determined in consideration of the thickness of the hub.

With the reference plate configured in this way, any standard sample can be attached by simply attaching the substrate section 1 to the clamp mechanism of the optical disk inspection device using the clamp section 2, without using any special jig or the like. Piece S0
~S11 can be set on top of the optical head. Moreover, since the area of each standard sample piece S0 to S11 is small, the uniformity is excellent. In addition, the position where the reflectance is 0% and the position where the transmittance is 100% are as follows.
No sample piece is provided and it is passed through.

FIG. 3 is a configuration diagram showing a state in which the reference plate of the present invention is attached to an optical disk inspection apparatus. The figure illustrates an example of a calibration operation in measuring the reflectance of an optical disk. In the figure, the above-mentioned figure 1 and 2
Components similar to those in the figures are designated by the same reference numerals. 4 is an optical disk clamping mechanism in the optical disk inspection apparatus, 41 is a turntable thereof, and 5 is an optical head. The optical head 5 includes a laser light source 51 that emits a constant amount of laser light, and an optical isolator 5.
2. Objective lens 53 that converges the laser beam emitted from the laser light source 51 and focuses it on the reflective surface 3 of the standard sample pieces S0 to S11, and the standard sample piece S0
~ Photo sensor 54 and photo sensor 5 that detect reflected light from S11 via optical isolator 52
It is composed of an amplifier 55 that amplifies the output of 4, and the like.

During such a calibration operation, any standard sample piece S0 to S1 can be read by simply rotating the substrate section 1.
1 can be set on the top of the optical head 5. Therefore, the standard sample pieces S0 to S1 at this time
By plotting the relationship between the value of 1 and the measured output S _{O and} interpolating between these measurement points, the entire measurement system including the optical system such as the objective lens 53 and the electric circuit system such as the photo sensor 54 and amplifier 55 can be calibrated. You can get all the curves at once. In addition, each standard sample piece S0 to S1
Since the height of the reflective surface in 1 is formed to be equal to the height of the recording film surface on a normal optical disc, the distance between the optical head 5 and the reflective film 3 is the same as when measuring the optical disc, and the focus servo Calibration operations can be performed under conditions that are close to those at the time of actual measurement.

In the above explanation, the calibration operation when measuring the reflectance of an optical disk was illustrated, but even if the measurement item is changed, the method of attaching the reference plate does not change, and the desired standard sample pieces S0 to S11 are can be easily set. Further, although the optical head 5 is of the type that irradiates the laser beam from below the optical disk, there is also one that irradiates the laser beam from above the optical disk. In such a case, since the position of the recording film surface of the optical disc is below the disc, the position and height of the reflective film surface or the transmitting film surface on the reference plate are also changed accordingly.

[Effect of idea]

As explained above, the reference plate for calibrating an optical disk inspection device of the present invention has a plurality of standard sample pieces valued at a predetermined reference value and a clamp portion that is commonly clamped by the clamp mechanism of the optical disk. The plurality of standard sample pieces are placed on the same circumference, and the position of the reflective film surface or the transmitting film surface and the height from the clamping surface of the plurality of standard sample pieces are set in the normal manner in which the plurality of standard sample pieces are clamped by the clamp mechanism. Since it is equipped with a substrate part that holds the optical disc so that it is aligned with the recording film surface of the optical disc, multiple standard sample pieces can be clamped using the same clamping mechanism as the optical disc without using any special jigs. A reference plate for calibrating an optical disk inspection device can be realized with a simple configuration, and any standard sample pieces can be set accurately on the top of the optical head in sequence by simply rotating the substrate part. .

[Brief explanation of the drawing]

1 and 2 are configuration diagrams showing one embodiment of a reference plate for calibrating an optical disk inspection device of the present invention, and FIG.
The figure is a configuration diagram showing an example of a state in which the reference plate for calibrating an optical disk inspection apparatus of the present invention is attached to an optical disk inspection apparatus. S0 to S11...Standard sample piece, 1...Substrate part,
2...clamp section, 3...reflection film, 4...clamp mechanism, 5...optical head.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A plurality of standard sample pieces valued at a predetermined reference value and a clamp portion that is commonly clamped by a clamping mechanism of an optical disk, and the plurality of standard sample pieces are The plurality of standard sample pieces are arranged on the same circumference, and the position of the reflective film surface or the transmitting film surface and the height from the clamp surface match the recording film surface of a normal optical disk clamped by the clamp mechanism. 1. A reference plate for calibrating an optical disk inspection device, comprising a substrate portion for holding the optical disk so as to hold the same. (2) The optical disk inspection according to claim 1 of the utility model registration claim, wherein each of the plurality of standard sample pieces has a predetermined value and has the same thickness as a standard optical disk. Reference plate for equipment calibration. (3) The plurality of standard sample pieces are used for calibration when measuring plate thickness, and each has a plate thickness according to a predetermined value and has the same reflectance as a standard optical disk. A reference plate for calibrating an optical disk inspection device according to claim 1 of the above-mentioned utility model registration.