JPH01201829A - Optical information recording and reproducing device - Google Patents

Abstract

PURPOSE:To reduce a load on a driving device itself and to easily correct a laser power by setting the power of a projecting spot suitable for a position on a medium by the command of a drive controller. CONSTITUTION:The driving device reads a track number on an optical disk 5 by a signal from an optical sensor 7, and sends the signal to the drive controller 14 at a controller side, and controls the laser power at the optimum level by the control of the controller 14. In other words, after a head position is detected from the track number, the real laser power at that time is compared with data in a laser power correction table 16 on which the optimum laser power is recorded at every position, then, the optimum laser power is sent to a control circuit 13 at the driving device side by a power correction signal M.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to control of laser power of a drive device for an optical information recording medium.The present invention can be suitably applied to an optical disk device.

[Conventional technology] Conventionally, optical disc mounting has been roughly divided into CAM (Cons).
tant Angular Velocity) and CL
V (Constant Linear Veloc)
ity), and in the CAW method, the angular velocity is -・
Since the linear velocity changes between the inside and outside of the disk, the power of the light source must be changed depending on the position on the disk in order to perform recording or reproduction.

FIG. 4 is a diagram showing a schematic configuration diagram of a conventional CAW type optical disk device.

In the figure, l is a light source such as a semiconductor laser, 2 is a collimator lens that collimates the light from the laser l, 3 is a beam splitter that splits the light into two, 4 is an objective lens that focuses the light, and 5 is a light source. Optical disc as an information recording medium, 6
7 is a sensor lens, and 7 is an optical sensor for autofocusing, autotracking, and obtaining an information signal reproduction signal. Further, IO is an optical head, 11 is a laser driver, 12 is a head position detection means such as a linear sensor, 1
3 is a control circuit that controls each part on the drive device side.

The drive device consisting of the above parts (for convenience of explanation, AT, AF circuits, etc. are omitted) is a drive controller 1 that performs overall control of the entire drive device.
4, and the drive controller 14 is also connected to a host computer 15 serving as a higher-level determining means.

The light emitted from the light source 1 is collimated into a parallel beam by the collimator lens 2, and then sent to the beam splitter 3. The light passes through the objective lens 4 and is focused on the information recording surface of the optical disk 5. The light reflected on the surface of the recording medium travels backward along the optical path, passes through the objective lens 4 and the beam splitter 3, and is focused by the sensor lens 6 onto the optical sensor 7). In the optical sensor 7, an AF, AT double signal information reproduction signal is obtained by a known method, and the AF,
Based on the AT@ number, the objective lens is driven by an unillustrated 7 actuator, and the optical spot is controlled to be in the optimum state for recording and reproduction.The optical head 10 is controlled by an unillustrated driving mechanism to move the optical disc 5. Driven in radial direction X.

Here, since the device shown in Fig. 4 uses the CAV method described above, the laser power P
must be changed as shown in Figure 3. Figure 3 shows the relationship between the head position and the laser power P. In general, the closer you go to the outer periphery, the faster the linear velocity becomes, so the laser power is increased. This indicates that it is necessary to reduce the laser power on the inner periphery.

Therefore, conventionally, the position of the optical head IO is detected by a separately provided head position detection means 12, and according to the detected value, a laser power correction signal M is sent to the control circuit 13 to control the output of the laser l.

By this control, the intensity of the modulated signal S for information recording or the non-modulated signal for reproduction from the control circuit 13 is adjusted according to the position on the recording medium, and recording and reproduction are respectively performed with the optimum light intensity.

[Problems to be Solved by the Invention] However, in this type of device, the position of the head lO in the drive device is detected by a linear sensor, etc., and the drive device accordingly corrects the laser power depending on the position of the head. Therefore, there is a drawback in that a special operation for this correction must be performed within the drive device in addition to other controls.

[Means for Solving the Problems] In view of the problems of the prior art described above, the present invention provides an optical information recording and reproducing device that can reduce the burden on the drive device and easily perform optimal laser power correction. It's about doing.

The above purpose is to provide a drive device that irradiates a light spot onto an optical information recording medium and reproduces and/or records information using the light that passes through the recording medium, and a drive that performs overall control of the entire drive device. In an optical information recording and reproducing device equipped with a controller, by reading address information in the recording medium, control is performed to set the power of the irradiation spot suitable for the position on the recording medium by commands from the drive controller. This is achieved by an optical information recording/reproducing device characterized by the following.

[Function] According to the optical information recording/reproducing apparatus as described above, it has become possible for the drive controller to directly control the laser power most suitable for the track number to be actually accessed.

[Example J Hereinafter, the optical information recording/reproducing apparatus according to the present invention will be described in detail based on a specific example.

FIG. 1 is a schematic configuration diagram showing an embodiment in which the optical information recording/reproducing apparatus of the present invention is applied to an optical disk device. In this figure, members having the same functions as those in FIG. 4 are designated by the same numbers, and a general description thereof will be omitted. Note that 16 schematically represents a laser power correction table.

In the non-embodiment, the track number of the track on the optical disk 5 is read from the information signal from the optical sensor 7,
The signal is sent to the drive controller 14 on the controller side.
The laser power is controlled to an optimum value under the control of the drive controller 14. That is, after detecting the head position from the track number, the actual laser power at that time is compared with the data in the laser power correction table 16 in which the optimal laser power for each position is recorded, and the optimal laser power is determined. The correction signal M is sent to the control circuit 13 on the drive device side.

FIG. 2 is a flowchart showing an example of the operation. An outline of the operation will be explained based on this flowchart.

First, an access operation is performed with a light beam set to a predetermined laser power that can perform AF and AT at any position on the optical disk (at step Sl
, 2), then the ID of the track (Identif
The drive controller 14 reads out the track number from the drive device m and medium c7) and sends it to the drive controller 14 (step S3). Based on the transferred track number, the drive controller 14 sets the optimum laser power for the track. In order to calculate the laser power correction data table 16 stored in advance,
and the current track number (step S4).
.

Next, the drive controller 14 transfers the calculated laser power control value (laser power correction signal) to the control circuit 13 (Step 2 S5). Drive 11
and control the laser power (step S6)
.

The present invention is not limited to the above-mentioned embodiments, and various modifications and applications can be made to the rotating portion.

In the embodiment described above, the data table 16 for laser power correction is stored in advance in the drive controller 14.
However, if this is stored in a recording medium in advance, read when the recording medium is inserted, and stored in the drive controller 14,
Appropriate corrections can be made for each recording medium, and future recording media with different required laser powers can be handled without any changes to the drive controller 14 (controller side) or drive device. There are advantages.

In the above embodiments, the case where the recording medium is disk-shaped is taken as an example, but even in the case of a reciprocating motion such as an optical card, the energy of the optical spot per unit area may vary due to the speed change of the recording medium. It is clear that the present invention is also applicable to

[Effect of the invention] As explained above, in order to record and reproduce data,
The drive device transmits the address information that is always read every time to the controller side, and the drive controller corrects the laser power for the head position based on the track number, thereby reducing the load on the drive device itself and achieving optimal laser power correction. This has the effect of easily realizing the following. Furthermore, the configuration of the present invention has the advantage of being more versatile than the conventional m configuration.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the optical information recording/reproducing apparatus of the present invention. FIG. 2 is an example of a flow chart for implementing the embodiment of FIG. Figure i3 is a graph showing the relationship between head position and laser power. FIG. 4 is a schematic configuration diagram showing a conventional CAW type optical disk device. 5: Optical information recording medium 10: Optical head 11: Laser driver 13 Nil J control circuit (drive device side) l4 Ni Drive controller (controller side) 15:
Host computer 16: Laser power correction table Agent Patent attorney Johei Yamashita

Claims (4)

[Claims] (1) A drive device that irradiates a light spot onto an optical information recording medium and reproduces and/or records information using the light transmitted through the recording medium, and a drive controller that performs overall control of the entire drive device. The optical information recording/reproducing device is characterized in that, by reading address information in the recording medium, a command from the drive controller controls setting the power of the irradiation spot suitable for the position on the recording medium. Optical information recording and reproducing device. (2) The optical information recording/reproducing apparatus according to claim 1, wherein the address information is a track number. (3) The optical information recording/reproducing apparatus according to claim 1, wherein the optical information recording medium is an optical disc. (4) The optical information recording/reproducing apparatus according to claim 1, wherein data for setting the power of the irradiation spot is recorded on the optical information recording medium itself.