JPH0673228B2 - Information recording device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a disc-shaped record carrier (hereinafter referred to as “disk”).
The present invention relates to an information recording device for recording information by optical means.

2. Description of the Related Art As a conventional information recording apparatus, for example, there is one described in the specification of JP-A-57-83538. About this Figure 3 ~
This will be described with reference to FIG. In FIG. 3, 1 is a disc, 2 is a photoresist applied on the disc 1, and 3 is a photoresist.
Is a motor which rotates together with the disk 1 at a constant rotation speed (for example, 900 rpm), 4 is a recording laser light source, and (A ₁ ) is a light beam emitted from the recording laser light source 4. This light beam (A ₁ ) enters the objective lens 10 through the half mirror 5, the light modulator 6, the lens 7 and the mirrors 8 and 9,
The objective lens 10 illuminates point a on the disk 1. When the light beam (A ₁ ) has a dropout as shown in Fig. 4 (a), the dropout detector 12 outputs the dropout shown in Fig. 4 (b) from the output of the detector 11 which monitors the light beam (A ₁ ). Similarly, the dropout (I) is detected.

The light beam (B ₁ ) emitted from the He-Ne laser light source 13 for focusing passes through the intermediate lens 14, the polarization beam splitter 15, the λ / 4 plate 16 and the mirror 9, and enters the objective lens 10, The spot is illuminated. The reflected beam from the surface of the disk 1 passes through the objective lens 10, the mirror 9, the λ / 4 plate 16 and the polarization beam splitter 15 and enters the two-divided detector 17. A differential amplifier 18 is provided by the output of the two-divided detector 17.
The error signal detected by the control circuit 19 is input to the control circuit 19.
Drives the actuator 20 to automatically keep the focus on the disk 1. Also, the photoresist 2 on the disk 1
If there is a dropout due to scratches or dust on the surface,
The light beam (B ₁ ) is scattered by the surface of the photoresist 2 and the amount of light incident on the two-divided detector 17 changes as shown in FIG. 5 (a). Each output of the two-divided detector 17 that has detected the light quantity is added to the adder circuit 21, the output of the adder circuit 21 is added to the dropout detection circuit 22, and the dropout (II) is generated as shown in FIG. 5 (b). To be detected.

The address signal included in the signal when the information signal is recorded is taken out by the address get circuit 23 and added to the computer 24. Address data when Dropout (I) (II) is input to the computer 24 is stored in the memory of the computer 24. This reveals where the dropout is on the disc.
Reference numeral 25 is a modulator.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the above-mentioned conventional information recording apparatus, when there is no information such as address data for reading the recording radius position and angle in the recorded information signal, the recording radius position such as a linear scale is simply used. Only the radial position of the dropout was known by the device that detected Also, when displaying the number and size of dropouts, only the size in the circumferential direction was handled, so even if there are large dropouts in the radial direction, they are not counted, or even if they are counted, it is apparently a dropout. Are counted in the vicinity of the same angle, which is inconvenient for dropout data processing.

Means for Solving Problems In order to solve the above problems, the information recording apparatus of the present invention is
The detector that receives the reflected light from the recording surface of the light beam that does not participate in the recording irradiated to the recording surface of the disk-shaped record carrier, and the dropout on the recording surface is detected from the output of this detector, and the time width data of the dropout is detected. A dropout detector, a position detector for detecting a recording radial position on the disc-shaped record carrier, an angle detector for detecting a recording angular position on the disc-shaped record carrier, and the dropout detector When a dropout is detected, a storage device for storing the output data of the position detector and the output data of the angle detector, and the time width data of the dropout output by the dropout detector are stored in the position detector. Convert the dropout length in the circumferential direction in the output data and compare it with the preset circumferential reference length to determine the dropout. A first computing device that is similar and counts, and when the angular positions of a plurality of dropouts stored in the storage device are consecutively at the same angular position, it is counted as one dropout, and the counted dropouts are counted. And a second arithmetic unit for classifying the dropouts by calculating the radial length of the above and comparing it with a preset reference length in the radial direction.

Operation According to the above configuration, even if the recorded information signal does not include the radial position and the angular position or information equivalent thereto, the radial position and the angular position of the dropout location can be known and stored. Since the size of the dropout in the radial direction can be known from the angular position of the dropout stored in the device, when classifying and counting the size of the dropout, the size of the dropout in the circumferential direction and the size in the radial direction can also be used. You can even classify and count.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 is a block diagram of an information recording apparatus in one embodiment of the present invention, in which 31 is a disk, 32 is a photoresist coated on the disk 31, 33 is a motor which rotates together with the disk 31 at a constant rotation speed, and 34 is Recording laser light source, (A ₂ ) is a light beam emitted from the recording laser light source 34, 35 is a light modulator, 36 is a half mirror, 37 is a lens, 38 and 39 are mirrors, 4
0 is an objective lens, 41 is a He-Ne laser light source for focusing, (B ₂ ) is a light beam emitted from the He-Ne laser light source 41, 42 is an intermediate lens, 43 is a polarization beam splitter,
44 is a λ / 4 plate, 45 is a two-divided detector, 46 is a differential amplifier that takes the difference between the outputs of the two-divided detector 45, and 47 is a control circuit that controls the actuator 48 by the error signal detected by the differential amplifier 46. Yes, the actuator 48 moves the objective lens 40 up and down to automatically focus on the disc 31. 49 is a modulator that modulates the signal to be recorded (for example, FM modulation) and applies it to the optical modulator 35, 50 is a detector that monitors the intensity of the light beam (A ₂ ), and 51 is the output of the detector 50 to the light beam (A ₂ ). ₂ ) A dropout detector that detects the dropout, 52 is an adder circuit that sums the outputs of the two-divided detector 45, and 53 is a dropout detector that detects the dropout on the disk 31 from the output of the adder circuit 52. , 54 is a memory for recording the recording radial position and the angular position of the dropout, 55 is a linear scale for detecting the recording radial position, 56 is a rotation reference position detecting device,
Reference numeral 57 is a rotation reference position detecting device attached to the motor 33.
The object to be detected, 58 is N (for example, 10
5) Frequency generator that generates the pulse, 59 is the frequency generator with the output of the rotation reference position detector 56 as the reset input
A counter for counting the output pulses of 58, 60 is an arithmetic unit, and the arithmetic unit 60 detects the circumferential direction of the detected dropout by the set rotational speed N _T of the disc 31, the set track pitch P, and the output of the linear scale 55. And the radial size is calculated.

Next, the operation will be described. When a signal is recorded on the disc 31, a spiral locus 61 as shown in FIG. 2 (A) is drawn.
Now, when there is a dropout 62 as shown in FIG. 2B, the dropout output pulse width detected by the dropout detector 53 is t ₁ [sec]. At this time, if the relative velocity in the circumferential direction between the recording light beam (A ₂ ) and the disk 31 (hereinafter referred to as “linear velocity”) is V ₀ [μm / s], the size of the dropout in the circumferential direction. l ₁ [μm] is l ₁ = V ₀ × t ₁ = 2π RN _T t ₁ …………… V ₀ = 2π RN _T R: Length from center of disc 31 to recording position [μm] N _T : Disc It becomes 31 rpm [rps]. When classifying the size of the dropout according to the length in the circumferential direction, if the reference lengths l ₁₁ , l _12, etc. are set in advance, l ₁ calculated by the formula can be classified by size comparison. The detected dropout is stored in the memory 54 and is converted into the circumferential length of the dropout by the above equation by the arithmetic unit 60 to obtain the reference length.
It is classified by the size comparison with l ₁₁ and l ₁₂ . Here, the rotation speed N
_{Since T} is determined by the type of disc 31 to be recorded,
It is set in advance. Further, the radius data of the recording position is output from the linear scale 55 to the arithmetic unit 60.

In the memory 54, the radius data and the angular position at the dropout location are recorded. The counter 59 is reset once per rotation of the disk 31 by the output of the rotation reference position detection device 56, and counts up with the output pulse of the frequency generator 58. Therefore, the output of the counter 59 when the dropout occurs becomes the angular position data of the dropout. When there is a long dropout in the radial direction as shown in FIG. 2B, the dropout is detected in the vicinity of the same angular position over many rounds. Now, when a dropout is detected in the vicinity of the same angular position over n rounds, it is processed by the arithmetic unit 60 as one dropout. Radial size of this dropout l ₂ [μ
m] is l ₂ = nP ………………. Here, P [μm] is the track pitch width shown in FIG. When classifying the size of dropouts by the length in the radial direction, set a standard length l
_21, classifies controller compares the arithmetic unit 60, such as l ₂₂ and l _2.

EFFECTS OF THE INVENTION As described above, according to the present invention, even if there is no information indicating the radius and angle of the recording position such as address data in the recorded information signal, the position detector and the angle detector cause the drop. The radius and angular position of the place where the out occurs can be known. Also, by setting the reference radial and circumferential lengths, it becomes possible to classify and display the detected dropout sizes according to the actual size, and the size of the dropouts can be radial as well as radial. Classification display is possible even with the size of. As a result, conventional 1
What is considered as a plurality of independent dropouts, one by one, in the data is also processed as one dropout, which facilitates the disk evaluation.

[Brief description of drawings]

FIG. 1 is a block diagram of an information recording apparatus in an embodiment of the present invention, FIG. 2 is an explanatory view of a recording track and a dropout of a disc recorded by the information recording apparatus, and FIG. 3 is a conventional information recording apparatus. FIG. 4 is an explanatory diagram of a dropout generated in the recording laser beam and its detection signal, and FIG. 5 is an explanatory diagram of a detector output waveform and a detection signal due to the dropout on the disc. 31 …… Disc, 45 …… 2-division detector, 53 …… Dropout detector, 54 …… Memory, 55 …… Linear scale, 56 …… Rotation reference position detection device, 57 …… Detected object, 58… … Frequency generator, 59 …… Counter, 60 …… Computer

Claims (1)

[Claims] 1. A detector for receiving a reflected light from a recording surface of a light beam, which is not involved in recording, irradiated on the recording surface of a disk-shaped record carrier, and a dropout on the recording surface is detected from the output of the detector to drop. A dropout detector for outputting time width data of out, a position detector for detecting a recording radial position on the disk-shaped record carrier, and an angle detector for detecting a recording angular position on the disk-shaped record carrier, A storage device for storing the output data of the position detector and the output data of the angle detector when the dropout detector detects a dropout, and the time width data of the dropout detector for the position detector. Converts the dropout length in the circumferential direction from the output data, compares the dropout length with a preset circumferential reference length, and classifies the dropouts. When the angular position of the first computing device to be mounted and the angular positions of the plurality of dropouts stored in the storage device are continuously at the same angular position, they are counted as one dropout, and the counted radial direction of the dropouts is calculated. And a second arithmetic device for classifying the dropouts by calculating the length of the dropout and comparing it with a preset radial reference length.