JP2001256714A - Information reproducing and recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information reproducing and recording device whose reliability is secured even under severe temperature environment and whose operability and convenience are enhanced. SOLUTION: The starting of a reproducing operation and a recording operation or the like is propertly controlled by always monitoring the temperatures in the reproducing and recording device and judging whether the temperature is a proper operation starting temperature, a proper operation stopping temperature or a proper operation restarting temperature. Moreover, proper operating temperature ranges are set separately as to the reproducing of information and the recording of information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an optical information reproducing / recording apparatus such as a CD player and an MD player mounted on a vehicle such as an automobile.

[0002]

2. Description of the Related Art An optical information recording / reproducing apparatus such as a CD player and an MD player mounted on a vehicle such as an automobile is exposed to a temperature environment which changes drastically depending on the season and weather since it is mounted on a vehicle. Therefore, generally, a temperature sensor is provided in the apparatus, and when the temperature inside the apparatus rises or falls abnormally, this is detected and the operation of the apparatus is automatically stopped, and the device inside the apparatus is destroyed due to abnormal temperature, and the quality is deteriorated. Has been prevented.

[0003]

Generally, an optical information reproducing apparatus such as a CD player for reproducing information recorded on an optical recording medium includes a light source such as a laser diode for optically reading recorded information. The optical reading means irradiates a laser beam onto the recording surface of the disc, extracts a modulation component contained in the reflected light, and reproduces the recorded information.

However, a laser diode as a light source is a semiconductor element, and has a problem that when it is operated at a high temperature, it is destroyed in a short time. Therefore, the conventional optical information reproducing apparatus employs a configuration in which the temperature of the optical reading means is monitored, and when the temperature exceeds a predetermined temperature, the operation of the optical reading means is stopped. Under such a configuration, if the operation of the optical reading means is stopped and then the operation is resumed when the temperature drops below the predetermined temperature, the heat generated by the re-operation and the preheating remaining in the apparatus are combined. Therefore, immediately after the operation, the temperature of the optical reading means exceeds the predetermined temperature, and the operation must be stopped again, which is inconvenient.

On the other hand, in an optical information recording / reproducing apparatus such as an MD player, not only information is reproduced but also information is recorded, so that it is necessary to drive a laser diode with a larger power during recording than during reproduction. The heat generated by the optical reading means including a light source such as a diode also differs greatly between recording and reproduction. Therefore, when an optical information recording / reproducing device such as an MD player is mounted on a vehicle, in consideration of a severe environmental temperature change due to being mounted on the vehicle, a finer temperature monitoring that takes into account the difference in heat generation during recording and reproducing information is considered. Required.

[0006] That is, an object of the present invention is to provide an information reproducing / recording apparatus which can maintain the reliability of the apparatus even under a severe temperature change and can operate properly.

[0007]

SUMMARY OF THE INVENTION The present invention relates to an information reproducing / recording apparatus for recording information on an information recording medium and reproducing the recorded information, wherein the apparatus processes an input signal to generate a write signal to the recording medium. Signal processing means for generating, an information writing means for writing the write signal on the information recording medium, information reading means for reading information recorded on the information recording medium to generate a read signal, and a signal for reading the read signal. A signal processing means for processing to generate an information reproduction signal, a temperature detection means for detecting the temperatures of the information writing means and the information reading means, and a detection value from the temperature detection means,
Control means for controlling the operations of the information writing means and the information reading means, wherein the control means operates the information writing means and the information reading means only when the detected value is within a first temperature setting range. The operation of the information writing means and the information reading means is stopped when the detected value exceeds a second temperature setting range, and the operation is performed when the detected value falls within a third temperature setting range. The information writing means and the information reading means are controlled so as to allow the operation to be restarted, and the information writing or reading operation can be individually set for the first to third temperature ranges.

[0008]

FIG. 1 shows a magneto-optical recording type writable disk player which is an information reproducing / recording apparatus according to the present invention. In FIG. 1, a system control unit 1
Reference numeral 0 mainly comprises a microcomputer for controlling the operation of the entire apparatus, and executes a main program (not described) stored in the memory unit 11 step by step in synchronization with a built-in clock. Note that R in the memory unit 11
An OM (Read Only Memory) table portion includes operation reference temperature ranges T1, T2, T3, which will be described later.
Each value of T1 ', T2', T3 'is set.

The display section 12 and the operation section 13 are provided on a console panel when a user handles the apparatus. The display section 12 is composed of a liquid crystal panel or a light emitting diode for displaying the state of the apparatus. Is composed of a keyboard or a switch group for inputting an instruction for an operation mode such as a reproduction or recording mode of information. The temperature sensor 14 is made of a semiconductor for temperature detection such as a thermistor or a diode, and detects the temperature of an optical reading unit (not shown) including a laser diode 16 and a light receiving unit 18, particularly, the temperature near the laser diode 16. Also,
The temperature detection unit 15 detects a change in the resistance value, voltage, or current value of the sensor 14 due to a temperature change, converts the change into a digital temperature detection value, and supplies the digital value to the system control circuit 10.

The laser diode 16 is excited by an output current of a laser diode driving section (hereinafter, referred to as an LD driving section) 17 and emits a laser beam. After passing through the beam splitter 20, the laser beam is converged by the condenser lens 21 and forms a beam spot on the surface of the magneto-optical disk 22. The light reflected from the disk surface is reflected by the beam splitter 20, enters the light receiving unit 18 including a light receiving element such as a phototransistor or a photodiode, and is converted into an electric signal as a reproduction signal of information recorded on the disk. You. The signal is demodulated and digitally /
After processing such as analog conversion, the signal is returned to an audio signal such as music and output from the audio signal input / output unit 26 to a speaker via an amplifier circuit (not shown).

On the other hand, an external audio input signal is
The signal is supplied to the signal processing unit 25 via the audio signal input / output unit 26. The signal processing unit 25 performs processing such as analog / digital conversion and coding on the audio input signal, prepares a format as a signal to be recorded on the disk, and supplies this to the magnetic head driving unit 24. The magnetic head driving unit 24 generates a magnetic head driving current based on the supplied recording signal, and thereby the recording magnetic head 2
3 is excited, and the magnetic film of the magneto-optical disk 22 is magnetized to record information on the disk 22.

In consideration of the characteristics of the magneto-optical recording disk, the system control unit 1 records information on the disk.
0 activates the LD driver 17 and activates the laser diode 16
Is excited at a high output, and the recording spot on the surface of the magneto-optical disk 22 is heated to a temperature higher than the Curie point. The operation of the apparatus shown in FIG. 1 in the information reproduction mode will be described below.

The system control unit 10 interrupts the operation processing subroutine in the information reproduction mode shown in FIG. 2 into a main routine that is always executed in synchronization with the internal clock, for example, and executes it at predetermined intervals. In accordance with the subroutine, the system control unit 10 constantly monitors whether or not a reproduction start command has been received from the operation unit 13 (step 10).
When the user performs a reproduction start operation on the operation unit 13, a reproduction start command is supplied from the operation unit, and the system control unit 10 transmits a laser diode 1 from the temperature detection unit 15 based on the instruction.
6 is read, and it is determined whether or not the value is within a reproduction start temperature range T1 preset in a ROM table of the memory unit 11 (see FIG. 4). Step 11).

If the detected temperature value is within the range of T1, the system control section 10 starts a reproducing operation (step 12).
That is, the system control unit 10 drives the magneto-optical disk 22 and optical reading means (not shown) including the laser diode 16 by a spindle motor and a servo mechanism (not shown) in the apparatus, and
Irradiates the information recording surface of the disk 22 with a laser beam. When the beam is reflected by the magnetic film on the information recording surface,
Polarized light corresponding to the magnetization direction of the magnetic film is received by the so-called Kerr effect. The polarization of the reflected beam is detected and demodulated by the light receiving section 18 and the information reading section 19, so that the information recorded on the disk 22 is demodulated and reproduced.

While the apparatus is performing the processing operation in the reproduction mode, the system control unit 10 periodically monitors the output of the temperature detection unit 15 and stops the reproduction when the detected temperature value is set in the ROM table of the memory unit 11. It is determined whether the temperature is within the temperature range T2 (step 13). If the detected temperature value is within the range of T2, the system control unit 10 monitors whether or not a reproduction stop command has been received from the operation unit 13 (step 14). Is repeated, and if a stop command is received, the operation of reproducing the information recorded on the disk 22 is stopped, and the disk 22 is ejected (step 16).

If the detected temperature value exceeds the regeneration start temperature range T1 in step 11, and
If the temperature exceeds the regeneration stop temperature range T2 in 3,
The system control unit 10 displays an alarm on the display unit 12 indicating that the reproduction operation is not possible because the temperature environment of the apparatus is abnormal, and automatically stops the reproduction operation (step 1).
5). After the reproduction operation is stopped, the system control unit 10 monitors whether or not a reproduction stop command is received from the operation unit 13 (step 17). When the stop command is received, the alarm display is reset, and the process proceeds to step 16 to perform the reproduction operation. Is stopped, and the disc 22 is ejected. If the stop command has not been received, the system control unit 10 re-inputs the temperature detection value from the temperature detection unit 15 and determines whether or not the value is within the regeneration restart temperature range T3 set in the ROM table in advance. A determination is made (step 18). If the detected temperature value is outside the range of T3, the system control unit 10 returns to step 17 and repeats the monitoring procedure. If the detected value is within the range of T3, the alarm display is reset and the process proceeds to step 12 to reproduce. Resume operation.

The relationship between the regeneration start temperature range T1, the regeneration stop temperature range T2, and the regeneration restart temperature range T3 is such that the temperature range T3 falls within the temperature range T1, and the temperature range T
2 is such that the temperature range T1 falls within the range 2. That is, the temperature of the optical reading means (not shown) including the laser diode 16 rises and the reproduction stop temperature range T2
In order to restart the reproduction operation after the reproduction operation stops after exceeding the temperature, the temperature must fall within a reproduction restart temperature range T3 narrower than the reproduction start temperature range T1. Similarly,
Even when the temperature of the optical reading means decreases due to a decrease in the environmental temperature, after the reproduction operation is stopped beyond the reproduction stop temperature range T2 and the reproduction operation is restarted, the temperature must be smaller than the reproduction start temperature range T1. The temperature must fall within the regeneration restart temperature range T3.

Therefore, as compared with the case where the resumption of operation is judged based only on the reproduction start temperature range T1, the so-called hunting phenomenon, in which the optical reading means immediately repeats re-operation and re-stop due to temperature change, is avoided. can do. Next, the processing operation in the information recording mode will be described below. The system control unit 10 interrupts the information recording mode processing subroutine shown in FIG. 3 into a main routine executed in synchronization with the internal clock, and executes it at predetermined intervals.

The system controller 1 according to the subroutine
0 is to constantly monitor whether or not a recording start command has been received from the operation unit 13 (step 20). When the user performs a recording start operation, a recording start command is supplied from the operation unit 13, and based on the instruction, the system control unit 10 sends a recording start command from the temperature detection unit 15.
A temperature detection value of an optical reading means (not shown) including a laser diode 16 is fetched, and the value is stored in the memory unit 11.
Recording start temperature range T preset in the ROM table
1 ′ is determined (step 2).
1).

If the detected temperature value is within the range of T1 ', the system control unit 10 starts a recording operation (step 2).
2). That is, the system control unit 10 drives the magneto-optical disk 22 and an optical reading unit (not shown) including the laser diode 16 by a spindle motor and a servo mechanism (not shown) in the apparatus, and furthermore, an LD driving unit. By exciting the laser diode 16 via 17, a high-power laser beam is irradiated on the recording surface of the disk 22. After the magnetic film on the disk recording surface is heated to a temperature higher than the Curie point by the laser beam and demagnetized, it is re-magnetized by the magnetic field of the magnetic head 23 excited by the information recording signal from the magnetic head drive unit 24. Thus, information to be recorded is recorded on the magnetic film of the disk 22.

While the apparatus is performing a recording operation, the system control unit 10 periodically monitors the output of the temperature detection unit 15 and
It is determined whether or not the detected temperature value is within the recording stop temperature range T2 'set in the ROM table of the memory unit 11 (step 23). If the detected temperature value is within the range of T2 ', the system control unit 10 monitors whether or not a recording stop command has been received from the operation unit 13 (step 24). The procedure is repeated, and if a stop command is received, the operation of recording information on the disk 22 is stopped, and the disk 22 is ejected (step 26).

If the detected temperature value exceeds the range of the recording start temperature range T1 'in step 21 and if it exceeds the range of the recording stop temperature range T2' in step 23, the system control unit 10 Then, an alarm is displayed on the display unit 12 indicating that the recording operation cannot be performed because the temperature environment of the apparatus is abnormal, and the recording operation is automatically stopped (step 2).
5). After stopping the recording operation, the system control unit 10 monitors whether a recording stop command has been received from the operation unit 13 (step 27). If the stop command has been received, the alarm display is reset, and the process proceeds to step 26 to perform the recording operation. Is stopped, and the disc 22 is ejected.

If the stop command has not been received, the system control unit 10 inputs the detected temperature value again from the temperature detecting unit 15,
It is determined whether or not the value is within the range of the recording restart temperature range T3 'set in advance in the ROM table (step 28). If the detected temperature value is outside the range of T3 ', the system control unit 10 returns to step 27 and repeats the monitoring procedure. If the detected value is within the range of T3', the system resets the alarm display and proceeds to step 29. Then, after waiting for a certain period of time in a so-called pause state, the process returns to step 20, which is the start point of the recording operation mode.

The relationship between the recording start temperature range T1 ', the recording stop temperature range T2', and the recording restart temperature range T3 'is such that the temperature range T3' falls within the temperature range T1 '.
The relationship is such that the temperature range T1 'falls within the temperature range T2'. That is, after the temperature of the optical reading means (not shown) including the laser diode 16 rises and exceeds the recording stop temperature range T2 'and the recording operation is stopped, the temperature must be reduced to the recording start temperature range T1 to resume the operation. The temperature must fall within the 'recording restart temperature range T3' which is narrower. Similarly, even when the temperature of the optical reading unit decreases due to a decrease in the environmental temperature, after the recording operation is stopped beyond the recording stop temperature range T2 'and the operation is resumed, the temperature must be higher than the recording start temperature range T1'. It is necessary to stay within the narrow recording restart temperature range T3 '.

Therefore, the so-called hunting phenomenon, in which the optical reading means immediately repeats re-operation and re-stop due to a temperature change, is more likely to occur, as compared with the case where the re-operation is determined based only on the recording start temperature range T1 '. Can be avoided. In addition, in the present invention, the difference in the excitation power of the laser diode between the information reproducing mode and the information recording mode causes a difference in the temperature rise of the optical reading means including the laser diode. The recording start temperature range T1 'falls within the recording stop temperature range T2, the recording stop temperature range T2' falls within the reproduction stop temperature range T2, and the recording restart temperature range T3 'falls within the reproduction restart temperature range T3.

That is, in the information reproducing mode in which the excitation power of the laser diode is small, a wider temperature range is set for all of the start, stop, and restart of the operation than in the information recording mode in which the excitation power is large. . Therefore, according to the present invention, it is possible to perform only the reproducing process even in a temperature environment where the information recording process cannot be performed, while appropriately managing the operating environment of the laser diode used when recording and reproducing information.

[0027]

As described above in detail, according to the present invention, the operability and convenience as an information reproducing and recording apparatus can be improved while properly managing the use conditions of the information reproducing and recording apparatus.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a magneto-optical disk information reproducing / recording apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart showing an operation of the apparatus of FIG. 1 in an information reproduction mode.

FIG. 3 is a flowchart showing an operation of the apparatus of FIG. 1 in an information recording mode.

[Explanation of symbols]

 Reference Signs List 10 System control unit 11 Memory unit (including ROM table) 12 Device display unit 13 Device operation unit 14 Temperature sensor 15 Temperature detection unit 16 Laser diode 17 Laser diode drive unit 18 Light receiving element unit 19 Information reading unit 20 Beam splitter 21 Light collection Lens 22 Magneto-optical disk 23 Magnetic head 24 Magnetic head drive unit 25 Signal processing unit 26 Audio signal input / output unit

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Katsuaki Yamanoi 25-1 Nishimachi, Yamada-shi, Kawagoe-shi, Saitama F-term in Pioneer Corporation Kawagoe Factory 5D044 AB05 BC06 CC06 GK19 HH13 HH15 HH17 JJ01 JJ02 JJ03

Claims (7)

[Claims] 1. An information reproducing apparatus for reproducing information recorded on an information recording medium, comprising: information reading means for reading information recorded on the information recording medium to generate a read signal; Signal processing means for generating an information reproduction signal by signal processing, temperature detecting means for detecting the temperature of the information reading means, and information reading operation of the information reading means based on a detection value from the temperature detecting means. Control means for controlling the read operation of the information reading means only when the detected value is within the first temperature set range, and the detected value is set at the second temperature set range. When the detected value exceeds the third temperature setting range, the reading operation of the information reading unit is stopped, and when the detected value falls within the third temperature setting range, the reading operation of the information reading unit is restarted. Information reproducing apparatus according to claim. 2. The first temperature setting range is wider than and includes the third temperature setting range, and the second temperature setting range is wider than and includes the first temperature setting range. 2. The information reproducing apparatus according to claim 1, wherein: 3. An information recording apparatus for recording information on an information recording medium, comprising: signal processing means for processing an input signal to generate a write signal on a recording medium; and writing the write signal on the information recording medium. Information writing means, temperature detection means for detecting the temperature of the information writing means, and control means for controlling an information writing operation of the information writing means based on a detection value from the temperature detection means; Means for permitting the writing operation of the information writing means only when the detected value is within the first temperature setting range, and writing operation of the information writing means when the detected value exceeds the second temperature setting range. And stopping the writing operation of the information writing means when the detected value falls within a third temperature setting range. 4. The first temperature setting range is wider than and includes the third temperature setting range, and the second temperature setting range is wider than and includes the first temperature setting range. 4. The information recording apparatus according to claim 3, wherein: 5. An information reproducing / recording apparatus which records information on an information recording medium and reproduces the recorded information, comprising: a signal processing means for processing an input signal to generate a write signal to the recording medium; Information writing means for writing the write signal on the information recording medium; information reading means for reading information recorded on the information recording medium to generate a read signal; signal processing of the read signal to generate an information reproduction signal Signal processing means for detecting the temperature of the information writing means and the information reading means; and controlling the operations of the information writing means and the information reading means based on the detection values from the temperature detecting means. Control means for controlling the information writing means and the information reading means only when the detected value is within the first temperature setting range. When the detection value exceeds a second temperature setting range, the operation of the information writing means and the information reading means is stopped, and when the detection value falls within a third temperature setting range, the information writing means and An information reproducing / recording apparatus, wherein the information reading / recording apparatus performs control for permitting restart of the operation of the information reading means. 6. The first temperature setting range is wider than and includes the third temperature setting range, and the second temperature setting range is wider than and including the first temperature setting range. 6. The information reproducing / recording apparatus according to claim 5, wherein: 7. The information reproducing / recording apparatus according to claim 6, wherein a temperature range can be set individually for each of the information writing operation and the information reading operation with respect to the first to third temperature ranges.