JPS58199443A - Optical information recording device - Google Patents

Abstract

PURPOSE:To evaluate the quality of a laser and a record carrier, by detecting a dropout of laser light and dust and a flaw on a recording surface. CONSTITUTION:Laser light from a recording laser 4 passes through a half-mirror 26 and is detected by a photodetector 27 and a comparator 28 detects its dropout. Laser light from a focusing laser is irradiated to an optical disk 1 after passing through an intermediate lens 12, polarization beam splitter 13, lambda/4-wavelength plate 14, mirror 9, and objective 10 and its reflected light is detected by a photodetector 15 and added by an adding circuit 24, so that a dropout detecting circit 25 detects dust and a flaw on the disk 1. Those data are stored in the form of corresponding addresses on the optical disk and the quality in recording is evaluated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical information recording device, and relates to an optical information recording device, in which the light intensity of a laser beam (for example, Ar+ laser) used as a recording light source is determined when information including a video signal is optically written onto a disc-shaped record carrier. The purpose of this research is to clarify the quality of optical recording by detecting scratches and dust on the recording surface of the sudden AiRozzo and disc-shaped record carriers, and collecting information on these dropouts. It is. - Optical information recording in which information is written onto a disk using a laser beam has been conventionally performed, and the recording apparatus mainly has a configuration as shown in FIG. The optical information recording carrier is a disc-shaped glass plate (1) coated with a photoresist (2), and is rotated at a constant number of revolutions (2) by a motor (3).
For example, it rotates at 1800 rpm). Light beam (A) emitted from a recording laser light source (4) (for example, Ar+laser) + i optical modulator (5), /% - humirar (
6), enters the objective lens member through the lens (7), mirror (8), and mirror (9). Mi Ra(?) is Ar
It has the property of transmitting + laser light (', λ = 4579λ), but conversely reflecting He-Ne laser light (λ = 6828λ). The light beam incident on the objective lens QO is transmitted to the optical record carrier (a) by the objective lens Ql).
The light is irradiated and focused on a point.

However, a disk-shaped record carrier (hereinafter referred to as a disk) rotates at a constant number of rotations, and the disk has irregularities on its surface and
Because the disk has warpage and inclination as shown in the figure, it is not always possible to focus on the disk surface. For this reason, it has an automatic focus control device.

The light beam emitted from the focusing He-Ne laser Q1 (
Sun is intermediate lens (to), polarizing beam splitter (to)
, the λ/4 plate (b), and the objective lens α through the mirror (9).
The light enters Q and is irradiated to point (a) on the disk surface. The reflected beam from the disk surface is passed through the objective lens QO and the mirror (9
), the λ/4 plate α♦, and the polarizing beam splitter (to), and enter the two-split detector (b). The vertical movement ΔX of the isk surface is shown in Figure 8 (a) on the two-part detector (total).
This appears as the movement of the beam as shown in . This movement is detected by the differential amplifier and applied to the control circuit (b).

The output of the control circuit Q1) drives a linear motor to compensate for the vertical movement of the disk surface, and automatically maintains the focus on the disk.

The input video signal is FM modulated by the FM modulator (6), and the intensity of the light beam is modulated by the optical modulator (5) as shown in FIG. 8(b). Also, the light intensity P is the irradiation point (a
) is controlled by the radial position of the

Further, the modulated light beam (A/) separated by the half mirror (6) enters the optical detector (1). The output of the detector is an FM demodulator! (2) demodulated and TV
Monitor with a monitor. By looking at this monitor slope, we check the signal during recording.

In such recording devices, dropout detection is not performed, and as a result, it is not possible to evaluate the quality of the recorded record carrier at all.

In view of these points, the present invention clarifies the position and extent of the two points considered to be the cause of dropouts on the record carrier, using address information included in the video signal. This is what I did. drop,
As has long been known, one of the causes of out-of-print is dust on the record carrier and scratches on the resist surface, and the other is
One is the sudden attenuation of the light intensity of the recording laser beam as shown in FIG. 4 (hereinafter referred to as laser beam dropout).

Dropouts caused by these causes should be clarified by clarifying the dropouts contained in the recorded carrier.There are many processes to make a disc, especially video discs, and one of these processes is the dropout of optical recording. It is thought to play an important role in the quality control of processes, as it serves as the basis for evaluating dropouts in other processes.

Therefore, the present invention provides an optical system including a recording laser and an objective lens that focuses a modulated laser beam obtained by intensity-modulating the recording laser beam onto a disk-shaped record carrier, and a rotation device that rotationally drives the disk-shaped record carrier. A recording device for optically recording video signals and audio signals including address information, comprising: a first optical detector for observing the intensity of the recording laser beam; and a recording device for receiving the output of the first detector; a first detector that detects a dropout of the laser beam; a second optical detector that irradiates a recording surface with a laser beam that is not involved in recording through the objective lens and receives reflected light from the recording surface; A second detector detects dust and scratches on the recording surface in response to the output of the detector, and when the first and second detectors generate an output pulse, the address data in the recording signal is detected. The intended purpose was achieved by configuring the device to store the output pulses in memory and count the number of output pulses.

Embodiments of the present invention will be described below based on the drawings. Fifth
The figure shows a recording device of one embodiment.

If there is dust or scratches on the resist surface at the irradiation point (a) on the disk surface, the light beam (the light beam) will be scattered by the disk surface, reflected by the disk surface, and the objective lens (lt), tler (9),
The amount of light incident on the detector OQ through the λ/4 plate a4 and the polarizing beam splitter changes as shown in FIG. 6(a). Since the detector 0 is a two-part detector, the output of each detector is added to the adder circuit to detect the amount of light.゛The output of the adder circuit (c) is added to the dropout detection circuit (2), and the dropout
l Generate cloud pulse (1). The dropout detection circuit) will be explained in detail in FIG.

The output of the adder circuit as shown in Fig. 6(a) is the LPF shown in Fig. 7.
■ is added to the comparator (to). The output of LPFC1υ is a voltage divider (2
) to create a threshold voltage Vch, which is added to the comparator. The output of the comparator So is a dropout pulse (1) as shown in FIG. 6(b).

The reason for this configuration is to counteract the change in reflectance caused by the He-Ne laser, the disk, and the resist layer (2).
(e) to the photodetector) as shown in FIG. 8(a), and is added to the comparator (2), where the
Create a dropout pulse (1) as shown in figure (b).

When performing optical recording, an address signal contained in a video signal is extracted by an address get circuit (2) and applied to a computer (to). Dropout detection circuit (2
) and the output of the comparator (2), the address data when the dropout pulses (1) and (iris) are input to the combination 111 user (to) are memorized. This reveals where the dropout is located on the disc.

At the same time, a video signal is monitored by passing a modulated light beam (A/) to an optical detector (E) and an FM demodulator. However, the video signal of the FM demodulator (2) is not easily affected by dropout (I) and dropout (1). For this reason, dropout (1), dropout (1)
) to the dropout generation circuit to indicate dropouts on the video signal. By doing this, the dropout caused by the dropout (1) can be made to have a black level on the TV monitor screen, and the dropout caused by the dropout (1) can be made to have a black level on the TV monitor screen.
) to the white level.

This allows the state of dropouts to be easily seen on a TV monitor during optical recording. In this embodiment, the same thing can be done for the power-accepting PCM audio signal, which has been mainly explained with reference to the video signal, and dropouts can be easily observed by replacing the TV monitor with speakers 4.

As described above, the present invention has the advantage that it is possible to easily evaluate the quality of a record carrier due to sudden dropouts of laser light and dropouts caused by scratches and dust on the recording surface of the disc-shaped record carrier.

[Brief explanation of the drawing]

Figure 1 is a block diagram of a conventional optical information recording device, and Figure 2 (ω
8(b) is a diagram showing the warpage and inclination □ of the disk, FIGS. Figure 4 is a diagram showing the dropout of the recording laser, Figure 5 is a configuration diagram showing an embodiment of the present invention, and Figures aE (a) and (b) are the dropout due to the He-Ne laser for focusing. A diagram explaining the detection operation of
Figure 7 is a detailed diagram of the dropout detection circuit, Figure 8 (a
) (b) is a diagram illustrating the dropout detection operation of the recording laser. (4) . . . Light source for recording, (6) . . . Optical modulator, ' Half mirror for (a) 1 < 11) (9)'
-...Mi? -1aQ...objective lens, (b)...He-Ne laser for focusing, (to) polarizing beam splitter -1)...2 division D, itector, -...F
M modulator, members... optical detector, (2)... FM demodulator, (2)... TV monitor, (to)... dropout generation circuit, (2)... adder circuit, (H)... )...drop, out detection circuit, to)...half = low tide = light detector, to 5)...comparator, wire...
...Address get circuit, Zeng...Ministry of Computer. (r, 0<ft1)...Dropout pulse agent Yoshihiro Morimoto 1 Fig. 1 Q □ Fig. 3 (b) Fig. 4 Fig. 5, Fig. 6 Fig. 8', Fig.

Claims (1)

[Scope of Claims] 1. An optical system including a recording laser and an objective lens that focuses a modulated laser beam obtained by modulating the intensity of the recording laser beam onto a disk-shaped record carrier, and rotationally driving the disk-shaped record carrier. A recording device that optically records a video signal and an audio signal including address information, the recording device having a rotating device that optically records a video signal and an audio signal including address information, a first optical detector that observes the intensity of the recording laser beam;
a first detector that receives the output of the first detector and detects dropout of the laser beam; and a laser beam that is not involved in recording that is irradiated onto the recording surface through the objective lens and receives reflected light from the recording surface. It has a second optical detector and a second detector that detects dust and scratches on the recording surface by receiving the output of the second detector, and the first and second detectors detect the output pulses. 1. An optical information recording device characterized in that, when a signal is generated, address data in a recording signal is memorized and the number of output parallels is counted. 2. A patent characterized in that when the output pulses of the first and second detectors are generated, address data is stored in memory for each detector pulse, and the detected pulses are counted. An optical information recording device according to claim 1.゛. '8. Claim 1, characterized in that when output pulses are generated in the first and second detectors, a dropout is created in the monitor signal detected from the modulated laser beam through a dropout generator. optical information recording device.