JPH0441460Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an optical recording/reproducing device that optically records or reproduces information, or records and reproduces information, and particularly relates to an optical recording/reproducing device for optical disc mastering. The present invention relates to the configuration of an optical element holding device in .

Configuration of a conventional example and its problems A conventional optical recording device will be explained using FIG. 2. In FIG. 2, light from a light source 1 is guided to a light modulator 2, where the light intensity is modulated by a desired signal, and then totally reflected by total reflection mirrors 3 and 4, which are then reflected by lenses constituting a beam expander system. 5 and 6 to a desired beam diameter, is totally reflected by a total reflection mirror 7, enters a recording lens 9 mounted on a voice coil 8, and is focused onto an information recording medium 10 mounted on a turntable 11. Tie. Reference numeral 12 denotes a drive motor for the turntable 11. These motors are housed in a transfer unit 13, and are transferred from a transfer drive system 16 via a transfer screw 15 between the recording lens and the recording medium in the radial direction of the recording medium. Perform relative movement along the line. In the optical recording device configured in this way, the aperture ratio of the recording lens 9 is about 0.9. In order to fully utilize the performance of a lens having such a high aperture ratio, it is necessary to make the optical axis incident on the recording lens 9 exactly coincide with the center of the recording lens 9, and to adjust it vertically. To adjust the optical axis, first, the total reflection mirrors 4 and 7 are adjusted to the desired height of the optical axis.
Adjust the total reflection mirror 4 so that it can be obtained in between, and confirm that it is parallel to the surface of the information recording medium. After that, the recording lens 9 is removed, light is irradiated onto the information recording medium 10, and the total reflection mirror 7 is set so that the reflected light from the information recording medium 10 coincides with the incident optical axis.
It is confirmed that the optical axis incident on the recording lens 9 is perpendicular within the plane of incidence. In this case, it has been confirmed in advance that the flatness and parallelism of the information recording medium 10 and the parallelism of the turntable 11 to the surface plate are within desired accuracy. After adjusting in this way, voice coil 8
It is necessary to attach the recording lens 9 mounted on the recording lens 9 and adjust the inclination of the recording lens 9 so that the reflected light from the incident surface of the recording lens 9 coincides with the incident optical axis.

As a method of aligning the optical axis bent by the total reflection mirror 7 with the optical axis of the recording lens 9 itself,
The voice coil 8 mounted with the recording lens 9 is
It was attached to a holder that could rotate around three axes. This configuration will be explained using FIGS. 3 and 4. FIG. 3 is a configuration diagram around the voice coil, and FIG. 4 is a partially sectional side view thereof. (Components in the figure that are the same as those in FIG. 2 are given the same numbers.
The same axis is also shown for the three axes of X, Y, and Z. ) In FIGS. 3 and 4, numeral 10 is an information recording medium composed of a glass master disk whose surface is coated with photoresist, and 8 is an information recording medium that holds a recording lens 9 and drives it in the vertical direction (Z-axis direction of the coordinates in the figure). The voice coil 14 is a fixing screw that fixes the voice coil 8 to the holder 24. Holder 24
A pivot screw 36 having a steel ball 36a fixed to its tip is attached near the center of the vertical portion of the pivot screw 36, and is fitted into a pivot bearing 46 of the fixing portion 27. A plurality of locking screws 26a to 26d are arranged around this pivot screw 36, and these screws push the holder 24 toward the fixing part 27 to fix it.
7 is engaged.

Further, the screws 26a to 26d have a spherical portion 34 on the head, as shown in FIG. 35 has a concave spherical surface on one side that fits with 34, and the other side is a flat pressing piece. Therefore, even if the holder 24 is tilted, the holder 24 can be pressed against the fixing part 27 without any force. Therefore, when the locking screws 26a to 26d are loosened, the holder 24 can freely move in three dimensions using the pivot bearing and the contact surface of the steel ball 36a as fulcrums.

Reference numeral 39 denotes an angle adjustment member fixed to the fixed part 27, and the adjustment screw 25 attached to this is engaged with the upper end of the holder 24 from both sides, and by adjusting these adjustment screws 25a and 25b from both sides. Thus, the holder 24 can be rotated around the pivot screw 36 in the direction of arrow A-A, that is, around the Y axis.

In addition, when adjusting the inclination of the holder 24,
By adjusting the tightening of the screws 26b and 26d, the holder 24 can be rotated around the X axis around the pivot screw 36, and by adjusting the tightening of the screws 26a and 26c, the pivot screw can be rotated. The holder 24 can be rotated about the Z-axis about 36.
Moreover, the holder 24 is fixed to the fixing part 27 by tightening 26a to 26d.

The fixed portion 27 is fixed to a movable stage 33 of a vertically movable table 32, and the focal position of the recording lens 9 is adjusted by movement of the vertically movable table 32 in the Z-axis direction. Also, the pivot screw 36
By moving forward and backward, the position of the recording lens 9 in the Y-axis direction is adjusted.

In this way, the voice coil actuator moves the recording lens 9 according to minute surface displacements of the recording medium.
It drives the recording lens up and down, and requires characteristics with no resonance peaks over a band up to about 10 KHz, except for the first-order resonance caused by the recording lens movable part.

However, in the conventional configuration described above, the holder 24 is positioned in the Y-axis direction away from the holder mounting surface in order to make the light from the mirror 7 enter the optical axis center of the recording lens 9 for optical adjustment. When the adjustment is made, push in the pivot screw 36 as shown in FIG.
As a result, the rigidity decreases and the voice coil actuator is driven, causing resonance, and many resonance peaks occur within the band required for focus servo, making it difficult to obtain the desired servo characteristics. There was a problem that there was no. Furthermore, since the tilt adjustment of the recording lens 9 with respect to the optical axis and the position adjustment in the Y-axis direction cannot be adjusted independently due to the structure of the holder,
In order for the recording lens output light to be emitted within about 100 μm and for the recording lens 9 to be tilted within several mrad with respect to the optical axis, it was necessary to repeat the adjustment many times.

The present invention solves the above-mentioned conventional problems, and aims to provide an optical recording/reproducing device that is easy to adjust and does not adversely affect the resonance characteristics of the voice coil.

Structure of the Invention In order to achieve the above object, the optical recording/reproducing device of the present invention includes a mirror that reflects a light beam from a light source at a right angle so as to be almost perpendicular to an information recording medium, and a mirror that reflects the light beam from the mirror. a recording lens that focuses light on an information recording medium, the recording lens being rotatably adjustable at least in a direction perpendicular to the optical axis of incidence on the recording lens and around two axes that are perpendicular to each other, The mirror has a mirror moving means that moves relative to the recording lens parallel to the optical axis of incidence on the mirror.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. It should be noted that the same reference numerals are given to those having the same functions and effects as those of the conventional example, and the explanation thereof will be omitted.

FIG. 1 shows an optical recording system according to an embodiment of the present invention.
FIG. 2 is a schematic configuration diagram of the main parts of the playback device. In FIG. 1, the configuration of the present invention differs from the conventional mirror 7 being fixed in the Y-axis direction, which is the radial direction of the information recording medium 10.
It is characterized in that the mirror 7 is configured to be movable in the Y-axis direction on the dimensional fine movement device 21 via the mirror holder 20. This movement is shown at 7' in FIG. The one-dimensional fine movement device includes a one-dimensional fine movement table 21a, a holder 21b, and a holding guide 21c. The configuration of the one-dimensional fine movement device is shown in FIG. 1b. According to such a configuration, the incident light on the recording lens 9 can be moved in the Y-axis direction by moving the one-dimensional fine movement table 21a while maintaining a perpendicular angle to the information recording medium 10. becomes possible. Further, the position of the incident light in the direction perpendicular to the above direction can be adjusted by adjusting the total reflection mirror 4 in FIG. Therefore, the voice coil 23 is attached to the voice coil holder 2.
4, the incident light position can be adjusted to the desired position using the one-dimensional fine movement table 21a and the total reflection mirror 4, and the voice coil holder 24 can be tilted around the X and Y axes. A structure having only two degrees of freedom for adjustment may be sufficient.

Furthermore, when using the voice coil holder 24 described above in conjunction with the components of the present invention, the mirror 7 can be moved in the Y-axis direction, so there is no need to push in the pivot screw 36 as described above. As shown in FIG. 6b, the distance between the holder 24 and the fixed part 27 is always leaning to the minimum required for tilt adjustment, and as a result, rigidity is maintained. In this case, the adjustment of the two degrees of freedom is performed by adjusting the voice coil holder 24 so that the reflected light from the recording lens 9 coincides with the incident optical axis.
After setting the four locking screws 26a~
26d, and it was confirmed that the characteristics of the voice coil 8 were not adversely affected.

Effects of the invention As described above, according to the invention, the conventional resonance problem can be solved by simply adding a transfer means that enables the movement of the mirror to the radial means of the information recording medium. In addition to making it possible to realize the servo characteristics of 1, the optical axis adjustment, which had to be repeated many times in the past, can be performed very easily.

[Brief explanation of drawings]

FIG. 1 shows an optical recording system showing an embodiment of the present invention.
2 is a schematic diagram of the overall configuration of a conventional optical recording device, FIG. 3 is a diagram of the configuration around the voice coil and recording lens in FIG. 2, and FIG. 4 is a diagram of the main parts of the reproducing device. Fig. 5 is a diagram showing the state in which the holder is pressed toward the fixing part by the locking screw, and Fig. 6 is a diagram showing the relationship between the holder and the fixing part by the pivot screw. It is. 5, 6... Lens, 7, 7'... Total reflection mirror,
8...Voice coil, 9...Recording lens, 10...
...Information recording medium, 21...One-dimensional fine movement table, 24...
...Voice coil holder, 26a-26d...Lock screw, 36...Pivot screw.

Claims (1)

[Scope of utility model registration request] A mirror that reflects a light beam from a light source at right angles so as to be substantially perpendicular to the information recording medium, and a recording lens that focuses the light reflected by the mirror onto the information recording medium, and the recording lens includes at least the The mirror is rotationally adjustable with respect to the recording lens in a direction perpendicular to the optical axis of incidence on the recording lens and about two axes perpendicular to each other,
An optical recording device characterized in that it has a mirror moving means that moves parallel to the optical axis of incidence on the mirror.
playback device.