JPH0480474B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a clamp hub pasting device, particularly an optical disk bonding substrate or an optical disk substrate for a write-once type optical disk device or an erasable type optical disk device. This invention relates to a clamp hub pasting device for pasting a clamp hub on one or both sides of a.

[Common technology]

Generally, when clamping an optical disk substrate, it is difficult to pass the spindle directly through the optical disk substrate.
There are problems such as wear and tear of the inner diameter hole of the optical disk substrate due to contact with the spindle, problems that mounting errors are likely to occur during automatic mounting, and problems such as the inner diameter hole of the optical disk substrate having an eccentricity of several tens of microns relative to the information signal recording track. Therefore, there is a problem that the information signal recording track becomes eccentric with respect to the center of rotation.

In particular, if the amount of eccentricity is large, tracking errors are likely to occur, which poses a serious problem.

Due to the above-mentioned reasons, write-once optical disk devices and erasable optical disk devices that require high precision adopt the magnetic clamp method according to the ISO standardization plan. It is in the direction of attaching a netstrumb. Moreover, optical disk substrates used in write-once optical disk devices and erasable optical disk devices generally have a double-sided bonded structure to protect the recording surface and correct substrate warping, so magnetic Tutclamps must be attached to both sides of the optical disk bonded substrate.

[Conventional technology]

FIG. 3 shows an optical disk manufactured using conventional technology.

In FIG. 3, the optical disk includes an optical disk substrate 1,
It has an inner circumferential spacer 4, a clamp hub 5, and an inner diameter hole 5a provided in the center of the clamp hub 5, and a suction plate 5b for accommodating a magnetic clamp.

When attaching a clamp hub to produce such an optical disk, apply adhesive in advance to the contact surface between the optical disk substrate 1 and the clamp hub 5, and attach the fitting part of the clamp hub 5 to the optical disk. By fitting into the inner diameter hole 5a of the substrate 1, the center of the inner diameter hole of the optical disk substrate 1 and the clamp hub 5
The bonding is performed so that the centers of the inner diameter holes 5a of the two are aligned.

[Problem that the invention seeks to solve]

However, in the above-mentioned conventional method of attaching a clamp hub to an optical disk, the clamp hub is attached so that the center of the inner diameter hole of the optical disk substrate matches the center of the inner diameter hole of the clamp hub, which is the rotation center. Since fitting errors between the fitting portion and the inner diameter hole of the optical disk substrate cannot be avoided, there is a drawback that the amount of eccentricity is large.

Furthermore, the inner diameter hole of the optical disk substrate normally has an eccentricity of several tens of microns with respect to the information signal recording track due to mechanical errors during punching. Even if the centers of the inner diameter holes coincide, there is also a drawback that the information signal recording track is eccentric with respect to the center of rotation.

[Means for solving problems]

The clamp hub pasting device of the present invention is capable of moving horizontally in the radial direction of an optical disk substrate.
a table, a clamp hub holder that is located above the X-Y table and holds the center of the inner diameter hole of the clamp hub at a specific position; and a clamp hub holder that is located above the X-Y table and moves horizontally with respect to the The X-Y table includes a microscope for observing the information signal recording track of the optical disk substrate, and an arithmetic unit that calculates the center coordinates of a circle from the coordinates of three arbitrary points on the circumference using a circle equation. An optical disk substrate is placed on the substrate, and the microscope is used to focus on one round section of the information signal recording track on the optical disk substrate, the coordinates of three arbitrary points in the section are measured, and the arithmetic unit calculates information from the coordinate measurement values. Find the center coordinates of the signal recording track, move the X-Y table by the amount of deviation of the center of the information signal recording track from the center of the inner hole of the clamp, and align the center of the information signal recording track with the center of the inner hole of the clamp hub. By attaching the optical disk substrate and the clamp hub after alignment, it is possible to eliminate eccentricity of the information signal recording track with respect to the inner diameter hole of the clamp hub, which is the center of rotation.

〔Example〕

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIGS. 1a and 1b are a plan view and a side view, respectively, showing an embodiment of the present invention.

FIGS. 2a and 2b are a plan view and a side view showing an example of an optical disk manufactured using the embodiment shown in FIGS. 1a and 1b.

The optical disk shown in FIG. 2 is an example of an air sandwich type optical disk laminated substrate 1' with a magnetic clamp attached as a clamp hub.
b An optical disk substrate 1 having an outermost periphery 1c and an inner diameter hole 1d, a magnetic clamp 2 having a guide ring portion 2a, a suction plate 2b, and an inner diameter hole 2c provided at the center of the suction plate 2b, and an outer circumference spacer 3. and,
It includes an inner circumferential spacer 4.

The clamp hub pasting device shown in FIGS. 1a and 1b places and fixes a bonded optical disk substrate 1' on an X-Y table 6. The X-Y table 6 has a feed mechanism section 7 and is movable by an X-direction drive section 8 and a Y-direction drive section 9. In addition, the storage recess 6a provided in the X-Y table 6 allows the same work as that of attaching the magnetic clamp 2 to one side of the optical disk bonded substrate 1' and then attaching the magnetic clamp 2 to the remaining surface. This is a storage section for a magnetic clamp provided so that it can be placed on the X-Y table 6.

On the other hand, the magnetic clamp 2 is fixed at a specific position by a holder 10. This holder 10 has a magnetized contact surface with the magnetic clamp 2, and attracts the attraction plate 2b of the magnetic clamp 2 by magnetic force. Furthermore, the holder 10 is provided with a tapered center defining convex portion 10a for positioning the magnetic clamp 2 by utilizing the inner diameter hole 2 of the magnetic clamp 2c.

Hereinafter, the center of the center defining convex portion 10a will be
Let it be the coordinate origin of the Y coordinate. Thereby, the magnetic clamp 2 is fixed so that the center of the inner diameter hole 2c coincides with the coordinate origin.

As mentioned above, with the optical disk bonded substrate 1' and the magnetic clamp 2 arranged, the microscope 11, which is located above the X-Y table 6 and is movable horizontally with respect to the X-Y table 6, is used to carry out the optical disk assembly. Information signal recording track 1a on laminated substrate 1'
_{Focusing on one round section of _}
Measure as (X ₃ , Y ₃ ). These coordinates are determined from the amount of movement of the microscope. Information signal recording track 1
You are free to select which one round section of the track a, but the innermost round section 1 of the information signal recording track area is selected.
b or the outermost periphery 1c is usually selected because it is easiest to measure.

Therefore, the microscope 11 must have at least a magnification that can distinguish between the information signal recording track area and the non-track area.

On the other hand, the calculation unit 12 calculates the coordinates P ₁ (X ₁ ,
Y ₁ ), P ₂ (X ₂ , Y ₂ ), and P ₃ (X ₃ , Y ₃ ), use the circle equation to obtain the center coordinate data, which is the center coordinates of the circle.
Perform calculations to obtain P ₀ (X ₀ , Y ₀ ). Coordinate value X ₀ ,
Y ₀ is determined by the following equations (1) and (2), respectively.

X ₀ = {[X ₁ ² + Y ₁ ² ) - (X ₂ ² + Y ₂ ² )] - (Y ₂ - Y ₃ ) - [X ₂ ² + Y ₂ ² ) (X ₃ ² + Y ₃ ² )] (Y ₁ −Y ₂ )} /{2[(X ₁ −X ₂ )(Y ₂ −Y ₃ ) −(X ₂ −X ₃ )(Y ₁ −Y ₃ )}} ...(1) Y ₀ = [(X ₁ ² + Y ₁ ² ) – (X ₂ ² + Y ₂ ² )] (X ₂ – X ₃ ) – [(X ₂ ² + Y ₂ ² ) – (X ₃ ² + Y ₃ ² )] (X ₁ – X ₂ )} / {2 [(Y ₁ − Y ₂ ) (X ₂ − X ₃ ) − (Y ₂ − Y ₃ ) (X ₁ − X ₂ )]} ...(2) Now, the information signal recording track If are concentric circles, one circumference section of each track is a circle. Therefore, the coordinate data of the three points measured by the microscope 11
By inputting P ₁ (X ₁ , Y ₁ ), P ₂ (X ₂ , Y ₂ ), and P ₃ (X ₃ , Y ₃ ) to the calculation unit 12, the center coordinate data P ₀ of the information signal recording track 1a can be obtained. (X ₀ , Y ₀ ) is found.

On the other hand, when the information signal recording track 1a is a spiral, one circumference section of the track is not a circle, but since the pitch of each track is generally as small as 1.6 μm, one circumference section of the track can almost be regarded as a circle. The calculation error in 12 is not a problem.

As described above, the center coordinate data P ₀ (X ₀ , Y ₀ ) which is the coordinate of the center of the information signal recording track 1a of the optical disc bonded substrate 1' on the coordinates with the center of the center defining convex portion 6a as the coordinate origin I was able to ask for

Therefore, by moving the X-Y table 6 by -X ₀ by the X-direction drive section 8 and by -Y ₀ by the Y-direction drive section 9, the center of the information signal recording track 1a of the optical disk laminated substrate 1' is aligned. Positioning can be performed so that the centers of the inner diameter holes 2c of the magnetic clamps 2 coincide.

Thereafter, an adhesive is applied in advance to the adhesive surfaces of the optical disk bonded substrate 1' and the magnetic clamp 2, and the holder 10 is lowered vertically to bond the magnetic clamp 2 and the optical disk bonded substrate 1'. As a result, the center of the information signal recording track 1a of the optical disc bonding plate 1' and the center of the magnetic clamp 2 can be aligned and bonded together.

Also, when attaching the magnetic clamp 2 to the opposite side, since the X-Y table 6 is provided with a recess 6a for storing the magnetic clamp 2,
Pasting work can be performed on the same X-Y table 6 using the same procedure as described above.

By pasting the magnetic clamps 2 as described above, the centers of the inner diameter holes 2c of the two magnetic clamps 2 are aligned with the center of the information signal recording track 1a of the optical disk bonded substrate 1'. Can be matched.

In the above embodiment, an example of an optical disk laminated substrate was described as the disk substrate, but this may also be an optical disk substrate.

Although the embodiments of the present invention have been described in detail above, various modifications can be made without departing from the spirit of the present invention, and the scope of the present invention is not limited by the above description.

〔Effect of the invention〕

The clamp hub pasting device of the present invention, instead of pasting so that the center of the inner diameter hole of the clamp hub and the center of the inner diameter hole of the optical disk substrate coincide with the center of the inner diameter hole of the optical disk substrate, unlike optical disks manufactured using conventional technology, information Find the coordinates of three points in one circumference of the signal recording track, use the equation of a circle to find the center of the information signal recording track, and then calculate the coordinates of the information signal recording track found when attaching the clamp hub to the optical disk board. By pasting so that the center of the information signal recording track coincides with the center of the inner diameter hole of the clamp hub, which is the center of rotation, it is possible to eliminate eccentricity of the information signal recording track with respect to the center of rotation.

[Brief explanation of the drawing]

Figures 1a and b are a plan view and side view showing an embodiment of the present invention, respectively, and Figures 2a and b are examples of an optical disk manufactured using the embodiment shown in Figures 1a and b, respectively. A plan view and a side view showing the 3rd
The figure is a partial cross-sectional view showing an example of an optical disk manufactured using a conventional technique. 1... Optical disk substrate, 1'... Optical disk bonded substrate, 1a... Information signal recording track, 1b
...Innermost circumference, 1c...Outermost circumference, 1d...Inner diameter hole,
2...Magnetic clamp, 2a...Guide ring, 2b...Adsorption plate, 2c...Inner diameter hole, 3...Outer circumference spacer, 4...Inner circumference spacer, 5...Clamp hub, 5a...Inner diameter hole, 5b...Adsorption plate, 6...
...X-Y table, 6a... Storage recess, 7...
Feeding mechanism unit, 8...X direction drive unit, 9...Y direction drive unit, 10...Holder, 10a...Center defining convex part, 11...Microscope, 12...Arithmetic unit, P ₁
(X ₁ , Y ₁ ), P ₂ (X ₂ , Y ₂ ), P ₃ (X ₃ , Y ₃ )...Coordinate data.

Claims (1)

[Claims] 1 An X-Y table that can be moved horizontally in the radial direction of the disk substrate according to the calculation results, and the X-Y
The above-mentioned X-
a clamp hub holder for attaching the clamp hub to the disk substrate on the Y table;
This X-Y table is provided above the X-Y table.
A microscope moves horizontally with respect to the table to observe the information signal recording track, and the center coordinates of the circle are calculated from the coordinates of three arbitrary points on the circumference of the information signal recording track using the circular equation. A clamp hub pasting device comprising: a calculating section for calculating