JPH02306432A - Information recording method for optical recording medium - Google Patents

Abstract

PURPOSE:To increase the overall quantity of information that can be recorded on an information recording medium by forming the information recording pits which can be recorded on plural unit information columns on a track. CONSTITUTION:The recording information are recorded on an optical recording medium 1 in columns for each unit information. At the same time, these unit information columns are set close to each other when the information are recorded on the medium 1. That is, plural information recording pits PT1 - PT3 are formed on each track and two pieces of unit information, i.e., the mark pits or space pits are recorded to each of pits PT1 - PT3. As a result, the spaces between adjacent tracks, i.e., the number of non-recording areas where no information is recorded can be decreased. Therefore a valid area where the information recording pits can be formed is increased. Thus the overall quantity of information can be increased for an optical disk.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a method for recording information on an optical recording medium used as an information storage medium such as an optical disk device.

(Prior Art) In recent years, for example, optical discs or optical cards have been widely used as recording media for devices that handle large amounts of information, such as image information recording and retrieval devices.

Hereinafter, an explanation will be given using an optical disc as an example. This disc-shaped optical disc has a plurality of concentric tracks formed along its outer periphery, and each track has a large number of pits as recorded information. For example, as shown in Fig. 4, truck TKm has pits PIT, , PIT2.
, PIT3, PIT4... are recorded. In addition, there are also pits PIT, PIT2, PIT3, PIT4 in the adjacent tracks TK and n+1, respectively.
... are recorded. The width X of each of these pits is set, for example, between 0.5 μm and 0.8 μm, and the length y of the pit is set, for example, to 2 μm. Further, the interval Z between the pit row arranged on track TKm and the pit row arranged on the adjacent track TKm+1, that is, the width 2 of the area where no information is recorded, is set, for example, from 0.8 μm to 1.1 μm. . Also, PIT1-PIT, , PIT2, PIT3, P, IT4・
Each of ... is unit information such as "1" or "
0" is recorded.

(Problems to be Solved by the Invention) As described above, in an optical recording medium such as a conventional optical disk, a plurality of tracks are formed adjacent to each other, and an area where no information is recorded is formed between these adjacent tracks. has been done. Therefore, the total amount of information that can be recorded on a single optical recording medium is limited depending on the total number of tracks. Therefore, it has been desired to further increase the total amount of information that can be recorded on a single optical recording medium.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a method for recording information on an optical recording medium that can record an even larger amount of information.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a method for recording information on an optical recording medium, which records information on an optical recording medium by irradiating light. In the method, the recorded information to be recorded on the optical recording medium is recorded so that each unit information is arranged in a column, and the information is recorded on the optical recording medium so that the unit information columns are arranged adjacent to each other in a plurality of columns. It is characterized by being made to do.

(Function) The present invention records recorded information in a recording layer formed on an optical recording medium, for example, so that each unit information is arranged in a column, and the unit information rows are arranged adjacent to each other in a plurality of rows. In this way, gaps between unit information strings are minimized or eliminated. Therefore, more recording information can be recorded by effectively utilizing the area of the optical recording medium.

(Example) Hereinafter, an example according to the present invention will be described in detail with reference to the drawings.

Hereinafter, a case where an optical disc is used as an example of an optical recording medium will be described.

First, the configuration of the optical disk device according to the present invention will be explained with reference to FIG.

The optical disc 1 is an information recording medium in which a pit row of information recording pits on which a plurality of units of information can be recorded is formed on a track. Further, in this embodiment, the optical disc 1 is a write-once optical disc on which data information can be additionally recorded only once.

As shown in FIG. 2, this optical disc 1 has a writing area 3 in which data information is written, and a writing area 3 for rewriting the data information if the writing state to this writing area 3 is defective. It has a replacement area 5.

The storage capacity of this spare area 5 is set to be several percent or less, for example, 1% or less, of the storage capacity of the write area 3. Also,
A spare area 5 provided around the write area 3 is formed of a rewrite area 5A and a management area 5B. In the rewrite area 5A provided at the outermost periphery of the optical disc 1, the relevant data information is rewritten when the write state to the write area 3 is defective as described above. Moreover, management information regarding data information written to the rewrite area 5A is written in the management area 5B provided between the write area 3 and the rewrite area 5A.

The write area 3 also includes a plurality of tracks in which data information is stored, ie, a first track TK1, a second track TK2 . ..., first track TK1. ..., each track of the final track TKx is formed, and data information is stored sequentially from the innermost track.

Further, each track is formed with a pit row of information recording pits in which a plurality of units of information can be recorded.

Next, referring to FIG. 1, a representative pit row formed on track TKn will be described in detail.

As shown in FIG. 1, a pit row of information recording pits PT1, PI3, PI3, PI3, . . . is formed on the track TKn. The width 2x of each of these information recording pits is set, for example, from 1 μm to 1.6 μm.

Furthermore, the length y of each information recording pit is, for example, 2 μm.
is set to .

Also, track TKn+1 adjacent to track TKn
width Z of the non-recording area where no information is recorded
is set, for example, from 0.8 μm to 1.1 μm.

The information recording pit PT is a space pit PT1a corresponding to "0" and a space pit PT corresponding to "0".
, b. Further, the information recording pit PT2 is composed of a space pit PT2a corresponding to "0" and a mark pitch hp"r2b corresponding to "1".

Similarly, the information recording pit PT3 is composed of a mark pit PT3a corresponding to "1" and a space pit PT3b corresponding to "0".

Similarly, a plurality of unit information, ie, one or more mark pits or space pits, can be recorded in each information recording pit.

Referring again to FIG. 3, the optical disc 1 is rotated by a spindle motor 7 while being placed on a turntable (not shown). An optical head 9 is arranged below the optical disc 1 so as to face it.

This optical head 9 is a so-called double beam type optical head that emits a laser beam for each unit of information formed on an information recording pit.

Next, the internal configuration of the optical head 9 will be explained in detail.

The semiconductor laser 11 outputs a beam of laser light. This laser light is applied to the objective lens 17 via the lens 13 and the half prism 15a. The optical disc 1 is arranged on the focal point of the objective lens 17,
A spot-shaped laser beam that has passed through the objective lens 17 is irradiated onto the track surface of the optical disc 1 . This objective lens 1
7 is provided movably in each of the tracking direction, which is the radial direction of the optical disc 1, and the focusing direction, which is a direction perpendicular to the radial direction of the optical disc 1. That is, a focus coil 19 and a track coil 21 for moving the objective lens 17 are provided. By passing current through the focus coil 19,
The objective lens 17 can be moved in the focus direction according to this current value. Similarly, by passing a current through the track coil 21, the objective lens 17 can be moved in the track direction in accordance with the current value. The laser beam reflected from the track surface of the optical disk 1 is split into two directions by the half prism 15b, one of which is incident on the condenser lens 25, and the other beam is incident on the condenser lens 27. A focus position sensor 29 is arranged on the focal point of the condenser lens 25, and the light condensed by the condenser lens 25 is converged by the focus position sensor 2.

Also, a track position sensor 3 is placed on the focal point of the condensing lens 27.
1 is arranged, and the light focused by the condensing lens 27 is focused by the track position sensor 31. The focus position sensor 29 has a built-in photoelectric conversion circuit, converts an input optical signal into an electrical signal, and outputs an electrical signal corresponding to the position in the focus direction. Further, the track position sensor 31 has a built-in photoelectric conversion circuit, converts an incident optical signal into an electrical signal, and outputs an electrical signal corresponding to the position in the track direction. The optical detector 35 is the semiconductor laser 1
1 and outputs a detection signal to the laser control circuit 41 .

The laser control circuit 41 is connected to each of the semiconductor laser 11 and the optical detector 35 built into the optical head 9, and controls the semiconductor laser 11 according to a detection signal from the optical detector 35.

The focus position sensor 29 is connected to the focusing control circuit 43 via an operational amplifier circuit OP2, and a signal corresponding to the position in the focus direction is sent to the operational amplifier circuit OP2.
The signal is applied to the focusing control circuit 43 via. This focusing control circuit 43 is connected to the focus coil 19 via an amplifier 45, and the focusing control circuit 43 outputs a signal corresponding to the amount of displacement in the focus direction, that is, a focus servo signal, to the focus coil 19 via the amplifier 45. do. Truck position sensor 31
is the tracking control circuit 4 via the operational amplifier circuit OPI.
7, and a signal corresponding to the position in the l/rack direction is applied to the tracking control circuit 47 via the operational amplifier circuit OP1.

This tracking control circuit 47 is connected to the track coil 21 via a diode 49, and the tracking control circuit 47 sends a signal corresponding to the amount of displacement in the track direction, that is, a tracking servo signal, to the track coil 21 via the amplifier 49. Output to. As described above, the objective lens 17 is moved in the tracking direction and the focusing direction by flowing currents according to the tracking servo signal and the focus servo signal to the tracking coil 21 and the focus coil 19. This allows the objective lens 17 to follow the amount of displacement of the optical disc 1.

The video circuit 51 is connected to the track position sensor 31 and also to the modulation/demodulation circuit 53 . Here, the signal output from the track position sensor 31 is
Since the unevenness of the information recording pits formed on the track is reflected, it is used as a reproduction signal of data information. The video circuit 51 binarizes this reproduced signal and outputs it to the modulation/demodulation circuit 53.

The modulation/demodulation circuit 53 includes a modulation circuit for modulating a data signal written to the optical disc 1 and a demodulation circuit for demodulating a read signal read from the optical disc 1 into an original data signal. The modulation/demodulation circuit 53 is the laser control circuit 4
1, and outputs a modulated signal modulated by the modulation circuit to the laser control circuit 41. Further, the modulation/demodulation circuit 53 is connected to a data buffer 57 via a timing circuit 55.
The write signal from the data buffer 57 is input via the timing circuit 55. Furthermore, when the modulation/demodulation circuit 53 inputs the binarized signal from the video circuit 51, that is, the read signal read from the optical disc 1,
This read signal is demodulated into the original data signal by a demodulation circuit, and this demodulated signal is output to the data buffer 57 via the timing circuit 55.

The data buffer 57 has a storage capacity of, for example, 128 bytes, and has a storage capacity of several tens of bytes. Area 5 with a storage capacity of bytes
7A and a region 57B.

Data information read from the rewrite area 5A of the optical disc 1 and management information read from the management area 5B are stored in the area 57A. The area 57B also stores data information to be written to the optical disc 1, read information read from the write area 3 of the optical disc 1, and the like.

Data buffer 57 is connected to host interface circuit 59 through path line BL. The CPU 61° is connected to the memory 63 and the I10 control circuit 65, respectively. Further, the host interface circuit 59 is connected to a host computer 91, which is an external device, via a path line BL2.

The read information read from the optical disc 1 is stored in the data buffer 57 and then transferred to the pass line BL.

Host interface circuit 59. The data is transferred to the host computer 91 via the pass line BL2.

The memory 63 stores various control programs such as a control program related to writing data information to the optical disc 1 and a control program related to replacement processing. CPU6
1 is a laser control circuit 41 via an I10 control circuit 65;
Focusing control circuit 43, tracking control circuit 4
7. Linear motor control circuit 67 and motor control circuit 69
That of.

The CPU 61 executes various control processes based on control programs stored in the memory 63.

The linear motor control circuit 67 is connected to a drive coil 71 of the linear motor, and by controlling this linear motor, the fixed portion of the optical head 9 is moved in the radial direction of the optical disc 1. The scale sensor 73 detects the position of the optical head 9 in the tracking direction.

Next, the action will be explained.

As shown in FIG. 1, a plurality of information recording pits are formed on each track, and each of these information recording pits has two
unit information, that is, mark pits or space pits, can be recorded.

That is, as is clear from the comparison with the conventional example shown in FIG.
The pit width of each information recording pit is set to twice the size, and each information storage pit is twice as large as the conventional example.
Can record twice the amount of information.

In addition, by forming information recording pits that can record multiple units of information, it is possible to reduce the interval between adjacent tracks, that is, the number of non-recording areas where information is not recorded, and the number of information recording pits can be reduced by this amount. Since the effective area in which pits can be formed increases, the amount of information that can be recorded on the optical disc as a whole can be further increased.

Note that in the embodiment shown in FIG. 1, each information recording pit is configured to be able to record two units of information.
The present invention is not limited to this, but the pit width of the information recording pit can be changed and set so that an appropriate number of unit information of three or more can be recorded.

Further, in the above-mentioned embodiments, a so-called write-once optical disc is used, on which data information can be additionally recorded only once. For example, it can be applied to a case where a read-only type and a rewritable type are used.

Furthermore, the optical head used in the embodiment shown in FIG. 3 is not limited to the so-called double beam method, but may be any suitable method, for example, an optical head such as the so-called double head method in which a head is provided for each unit of information. It can be configured as follows.

[Effects of the Invention] As explained above, according to the present invention, information recording pits in which a plurality of unit information strings can be recorded are formed on a track, so that the total amount of information that can be recorded on an information recording medium is further increased. can be increased.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a pit row of information recording pits formed on a track, FIG. 2 is an explanatory diagram showing a recording area of an optical disc, and FIG. 3 is an overall diagram of an optical disc device according to the present invention. FIG. 4 is an explanatory diagram showing a conventional example. 1... Optical disk 9... Optical head

Claims (1)

[Claims] In a method of recording information on an optical recording medium by irradiating light, the recording information to be recorded on the optical recording medium is recorded so that each unit information is arranged in a column, and the unit information column is arranged in a plurality of columns. 1. A method for recording information on an optical recording medium, characterized in that information is recorded on the optical recording medium in such a manner that the information is brought closer to each other.