JPS6318525A - Input and output device for optical disk - Google Patents

Abstract

PURPOSE:To speed up access time by using plural consecutive tracks in radial direction as one block and forming the tracks in the block by an inter-track in response to a code representing the information with respect to the position of an optical disk. CONSTITUTION:The tracks in a block are formed by inter-track pitch in response to a code representing the information relating the position of an optical disk. The 17 consecutive tracks in radial direction in one block are formed by a pitch in response to a code representing a block number NB corresponding to the track location, the inter-track pitch in the block is read and the block number NB is recognized from the code, then the location on the optical disk 1 is recognized easily. On the other hand, the input/output device 3 at a low speed coarse feeding reads the inter-track pitch of the disk 1 and the present location of the head 20 to the optical disk 1 in the embodiment is recognized easily. Thus, the access time to an object data is reduced very much.

Description

Detailed Description of the Invention Object of the Invention [Industrial Application Field] The present invention relates to an optical disc and its input/output device, and more particularly, to an optical disc on which information regarding the radial position of the optical disc is recorded, and the information thereon. The present invention relates to an input/output device for an optical disc that can suitably control an optical head to a target position using the following.

[Prior Art] Information recorded on an optical disc includes so-called address information indicating the recording position of the information.

Whether it's the frame number of a CAV disk, which is used exclusively for image recording, or the program time of a CLV disk, or the track number or sector number of an optical disk, which is used as an optical memory device, they are all the same information that indicates the location where information is recorded. The optical disc input/output device uses this information to achieve random access. This information is also used to send the optical head, which writes to and/or reads from the optical disk (hereinafter referred to collectively as access), to the position where the desired information exists at high speed. It also contributes to faster access.

[Problems to be Solved by the Invention] However, since such information indicating the location of information is usually written at the beginning of each frame or each sector, it is difficult to obtain the address information pre-recorded on the optical disc. However, there still remains the problem that it requires a rotation wait of at most one frame or one sector. Therefore, with conventional optical disks and their input/output devices, there is a limit to the reduction of access time in random access due to this rotational waiting time, and there is a problem in that speeds cannot be increased beyond -windows.

Structure of the invention [Means for solving the problem] In order to further speed up the access time,
The following two inventions were made. That is, the first invention relates to an optical disc, and as a means for solving the above problems, in an optical disc equipped with tracks for recording information, a plurality of tracks continuous in the radial direction are arranged in one block. year,
The structure is characterized in that the tracks within the block are formed with an inter-track pitch corresponding to a code representing information regarding the position of the optical disc.

On the other hand, the second invention relates to an input/output device for an optical disc, and as a means for solving the above-mentioned problem, a track-to-track pitch is formed at a pitch corresponding to a code representing information regarding a position on an optical disc. An optical disk input/output device that writes and/or reads information on an optical disk having a plurality of tracks, the head moving the optical head for writing and/or reading in the radial direction of the optical disk. a transfer means, a pitch detection means for detecting the inter-track pitch of the optical disk during the radial transfer, and a code configured by the detected pitch row to read information regarding the position on the optical disk. The optical head position control means includes a position information reading means and an optical head position control means for controlling the head moving means to control the optical head to a target position based on the read position information.

[Operation] In the optical disc of the first invention having the above configuration, the inter-track pitch of a plurality of radially continuous tracks within one block represents information regarding the position of the optical disc. On the other hand, in the optical disc input/output device of the second invention for writing and/or reading information to and from the optical disc, the pitch detecting means Detect the above-mentioned track pitch of the optical disc by
The position information reading means recognizes the code constituted by this pitch row and reads information regarding the position on the optical disk, and based on the read position information, the optical head position control means controls the head transport means to move the optical disc. Control the head to the target position.

[Embodiments] In order to further clarify the configurations of the two inventions described above, an optical disc and its input/output device as preferred embodiments of these inventions will be described next. FIG. 1 is a perspective view showing a schematic configuration of an optical disc 1 and an input/output device 3 that performs data writing and reading access to the optical disc 1. As shown in FIG.

As shown in the figure, the input/output device 3 includes a keyboard 5 and a CR
A terminal 9 equipped with a T-display 7, a printer 10 that prints bit images, an image scanner 12 that reads the original to be recorded as image data, a turntable 14 on which the optical disc 1 is placed, and a spindle motor that drives and rotates the turntable 14. 16. An optical head 20 that writes and reads data on the optical disc 1 using laser light, a head transport device 22 that transports the optical head 20 in the radial direction of the optical disc 1, and is connected to and controls each of these devices. An electronic control device 25 is provided.

The optical head 20 has a slider 28 supported by two guide shafts 26 and 27 so as to be movable by 1M, and the slider 28 includes an optical system for writing and reading. This optical system uses a semiconductor laser (not shown) as a light source, and is composed of a polarizing beam splitter that separates incident light and reflected light consisting of three beams, a tangential mirror, and an objective lens device 29 that performs focusing and tracking. This is a well-known device and is controlled by an electronic control device 25. A rack 30 is fixed to the side of the slider 28, and the head transfer device 22 is connected to a transfer motor 31.
．． Reduction gear box 33 configured together with encoder 32
It is meshed with the final stage gear 34 of. The final stage gear 34 is rotated using the transfer motor 31 as a drive source, and the amount of rotation thereof, that is, the amount of movement of the optical head 20 is detected by an encoder 32 connected to the rotation shaft of the final stage gear 34.

The electronic control device 25 that controls the optical head 20, head transfer device 22, etc., includes a well-known CPU 41, ROM 43, etc.
．． A terminal input/output port 47 and a motor drive circuit 48 are configured as an arithmetic and logic operation circuit centering on a RAM 44 and are mutually connected to these circuits via a bus 45. Input circuit 4
9. A head control circuit 50 and an image scanner input port 52 are provided.

The terminal input/output port 47 is connected to the terminal 9 and the printer 10, and the CPtJ41 inputs data from the keyboard 5 via this input/output port 47.
Data can be displayed on the CRT display 7 and printed out using the printer 10.

The image scanner input port 52 is connected to the image scanner 12, and the CPU 41 uses this input port 5.
2, an image of a document set on the image scanner 12 can be read. The read image data is temporarily stored in the RAM 44, and is further stored in the head control circuit 50 in accordance with commands input from the terminal 9.
The data can be outputted to the optical head 20 connected via the flexible cable 54 and written on the optical disc 1.

When writing or reading data, the optical head 20 must be moved to a position facing a predetermined track or sector, and these controls are controlled by the spindle motor 16. A motor drive circuit 48 connected to the transfer motor 31 and an encoder 3 of the head transfer device 22
This is realized by sending and receiving control signals via an input circuit 49 connected to 2.

The optical disk 1 has a plurality of concentric tracks ↑q (grooves), and data can be written on the track tg by magneto-optical recording using a laser beam. The written data is read using a laser beam that is weaker than the laser beam used for writing.
This is done using the Kerr effect.

The optical disc 1 of this embodiment has a track t as shown in FIG.
The pitch of c11 to tF16 is variable. In other words, one block is made up of a set of 17 tracks, and the widest groove track TGS is provided at the beginning of one block to form a start bit. The pitches of the tracks tc11 to ↑Q16 are determined by pi-phase modulation in accordance with a specific code.

The pitch of these tracks is determined by adjusting the photoresist l-layer PR formed on the glass disk GL to a specific code using a strong laser beam and a weak laser beam when producing the master disk for manufacturing the optical disk 1. It is determined by exposing at a pitch determined by That is, as shown in FIG. 3, if the width of the photoresist layer removed by irradiation with a weak laser beam is pQ, the width of the photoresist layer removed by irradiation with a strong laser beam is approximately twice that. By etching, track grooves with different pitches are formed in the glass 'E=GL. Although FIG. 3 shows the shape of the master disc, since the optical disc 1 is manufactured using this master disc, the relationship between the ridges and grooves is reversed. Therefore, the code represented by the shape shown in FIG. 3 is as shown in the bottom row of the figure.

The input/output device 3 described above can read the inter-track pitch formed in this way when the optical head 20 is running at low speed, and FIG. An example is shown.

Next, control when the input/output device 3 reproduces data using the above-mentioned optical disc 1 will be explained with reference to the flowchart shown in FIG. When reading data from the optical disc 1, the input/output device 3 of this embodiment executes the read control routine shown in FIG. A process is performed to input the name from the keyboard 5 through the terminal input/output port (step 100).

Next, from this file name, the track number and sector number of the optical disc 1 in which the data is recorded are determined, and processing is performed to determine the target track number TS for starting reading (step 110). This may be configured to be determined from the directory recorded on the optical disc 1, or may be configured to be determined from now on when the directory is recorded on other recording means, such as a flexible disk or a valve memory. good.

Once the target track number TS is known, the approximate position Hp on the optical disk 1 where the track with that number exists is known, and this is determined to find the block NB closest to the target track (step 120). As described above, since one block is composed of 17 tracks, the nearest block number NB can be determined by dividing the target track number TS by 17.

Next, the spindle motor 16 is driven via the motor drive circuit 48 to rotate at a constant speed, and the transfer motor 31 of the head transfer device 22 is driven to transfer the optical head 20 toward the outer circumference at high speed. (Step 130
). At the same time, the output of the encoder 32 is read through the input circuit 49 (step 140), and based on this it is determined whether the optical head 20 has reached the position Hp determined in step 120. This high-speed carrying continues until (steps 130 and 140)
, 150>.

When the optical head 20 reaches the position Hp, the transfer position
1 to reduce the feed speed of the optical head 20 and repeat the process of reading the pitch of the track groove of the optical disk 1 until a wide track tgs corresponding to the start bit is detected (step 170, 180>
.

When the start bit is detected (see Figure 2), the optical head 20 continues to move at low speed and reads the 16-bit inter-track pitch following the start bit (step 190). It is determined whether the code obtained by demodulating the code based on the pie-phase method matches the nearest block NB obtained in step 120 (step 200>. If it does not match, the next block is Then, the same process is executed again (steps 190 and 200).

When the two match, it is assumed that the optical head 20 has reached the block NB closest to the target track Ts.
Rack TS to target 1 while counting tracks sequentially
further moving the optical head 20 until step 210);
The data of the file specified to be read is sequentially read from the first sector in which it is stored to the end of the file (step 200>).Then, the read data is transferred to the C through the terminal input/output port 47.
The processing for displaying on the RT display 7 is performed (step 230), and the control routine is completed after being handled as rENDJ.

As explained above, in the optical disc 1 of this embodiment, the tracks in one block formed of 17 tracks continuous in the radial direction are blocks corresponding to the track positions (here, 1 to rack number). They are formed at a pitch corresponding to the code representing the number NB. Therefore, by reading the inter-track pitch within a block and knowing the block number NB from the code, the position on the optical disc 1 can be easily known.

On the other hand, the input/output device 3 of the present embodiment described above can read the inter-track pitch of the optical disc 1 in low-speed installation, and based on this, the current optical head for the optical disc 1 of the embodiment can be read. 20 can be easily found. Therefore, there is no need to stop feeding the optical head 20 in the middle of feeding the optical head 20 in the radial direction and read the address information (track number, sector number) recorded on each track, and the optical head 20 can be moved to the target at high speed. It can be transferred to truck Ts. As a result, the time required to access target data can be extremely shortened.

Although embodiments of each of the two inventions have been described above, the present invention is not limited to these embodiments in any way. For example, an optical disk that performs recording by forming holes instead of magneto-optical recording, It goes without saying that the invention can be implemented in various ways without changing the gist of the invention, such as the configuration of the input/output device.

As described in detail, the optical disc of the first invention has the excellent effect that information regarding the position of the optical disc can be read from the pitch between tracks within a block.

Moreover, the optical disc input/output device of the second invention has an advantage over the optical disc of the first invention in that the position on the optical disc can be easily known by detecting the pitch between tracks within the block. It has a great effect. Therefore, the optical head can be controlled at high speed with respect to the target position of the optical disc, and the access time to the optical disc can be shortened.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a schematic configuration of an optical disc 1 and its input/output device 3 as embodiments of the first invention and the second invention, and FIG. 2 shows an optical disc input/output device M3 in the embodiment. 3 is a flowchart showing a read control routine executed when reading data. 1... Optical disc 3... Input/output device 10...
・Printer 12... Image like 1? Su16・
...Spindle motor 20...Optical head 22...Head transfer device 2
5... Electronic control device 28... Slider 41...
cpu

Claims (1)

[Claims] 1. In an optical disc equipped with tracks for recording information, a plurality of tracks that are continuous in the radial direction constitute one block, and the tracks within the block are coded to represent information regarding the position of the optical disc. What is claimed is: 1. An optical disc characterized in that the optical disc is formed with a corresponding inter-track pitch. 2. An optical disc input/output device for writing and/or reading information on an optical disc having a plurality of tracks formed with a track pitch corresponding to a code representing information regarding a position on the optical disc, head transport means for transporting the optical head for writing and/or reading in the radial direction of the optical disc; pitch detection means for detecting the inter-track pitch of the optical disc during the transport in the radial direction; positional information reading means for recognizing the code formed by the pitch rows read and reading information regarding the position on the optical disk; and based on the read positional information, controlling the head moving means to move the optical head to the target position. An optical disc input/output device comprising an optical head position control means for controlling the position of the optical head.