JPH0731870B2 - Disk record playback device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a disc record reproducing apparatus of, for example, a CD (optical compact disc) type.

(Prior Art) Recently, in the field of audio equipment, a digital recording / reproducing system using PCM (pulse code modulation) technology is being adopted in order to achieve reproduction with as high a fidelity as possible.

In other words, this is called digital audio conversion, and the audio characteristics do not depend on the characteristics of the recording medium and can be markedly superior to those based on the conventional analog recording / reproducing method. This is because it has been established in principle.

In this case, a recording medium intended for a disk (disc) is called a DAD system, and its recording / reproducing system has been proposed such as an optical system, an electrostatic system, and a mechanical system. Regardless of which method is adopted, a playback device that plays back the disc is required to be able to satisfy various advanced control functions and performances that are not seen in conventional ones. There is.

That is, taking the CD type as an example, a metal thin film for forming pits (unevenness with different reflectance) corresponding to digital PCM data is deposited on a transparent resin disk with a diameter of 12 cm and a thickness of 1.2 mm. CLV (constant linear velocity)
Depending on the system, it is driven to rotate at a variable rotation speed of about 500 to 200 rpm, and it can be reproduced in a linear track king system from the inner circumference side to the outer circumference side with an engineering type pickup incorporating a semiconductor laser and a photoelectric conversion element. is there. This disc has a track pitch of 1.6 μm and a huge amount of information that can perform stereo reproduction on one side for about 1 hour is recorded in a program area (radius 25 to 58 mm) together with address data. Table-of-contents (TOC) data indicating the start address of each song number is digitized and recorded in the lead-in area (radius 23 to 25 mm).

For such a disc, the disc record reproducing apparatus has a large amount of information recorded on the disc. Therefore, in order to easily and selectively reproduce desired non-reproducing data, high-speed fast-forward and fast-reverse operations are performed. A sending function and a search function for automatically searching for a desired address can be provided. In addition, some disc record reproducing apparatuses are provided with a memory function capable of storing desired information so that the address of the data to be reproduced can be searched in a timely manner, in addition to the search function.

Various methods have been considered to improve the performance of such a disc record reproducing apparatus. For example, attempts have been made to improve the pickup feed motor in order to perform the search operation at high speed, and to improve the circuit necessary for the search operation. In addition, new circuits are being developed to speed up the pull-in of the CLV control system and to display the pickup position more accurately. However, at present,
The functions of the disk record reproducing device are not so high in speed and accuracy, and further improvement in performance is desired.

(Problems to be Solved by the Invention) The present invention has been made in view of the above circumstances, and an object thereof is to provide a disc record reproducing apparatus in which various functions of the disc record reproducing apparatus are improved in performance.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above-mentioned object, a disc record reproducing apparatus of the present invention is configured such that a plurality of data to be reproduced and their address data are digitized together, In a disc record reproducing apparatus for reproducing a disc record recorded at a constant linear velocity using a pickup for reading these data, a plurality of data to be reproduced and their address data are digitized together, and a constant linear velocity is obtained. In a disc record reproducing apparatus for reproducing a recorded disc record by using a pickup for reading these data, a search means for moving the pickup to a desired position of the disc record, and address data reproduced from the disc record. Of the disk record data using A means for obtaining a recording linear velocity or a value related to the recording linear velocity and a recording linear velocity or a value related to the recording linear velocity obtained by this means are used to perform the search operation of the searching means. (Operation) In the one configured in this way, the recording linear velocity of each disc record reproduced by this reproducing apparatus or a value related thereto is obtained to speed up the search operation and increase the accuracy. It is possible to obtain a higher performance disc record reproducing device.

(Embodiment) An embodiment of a CD type disc record reproducing apparatus to which the present invention is applied will be described with reference to the drawings.

First, an outline of the disc record reproducing apparatus in this embodiment will be described with reference to FIGS. 2 and 3.

FIG. 2 shows a front external view of the disc record reproducing apparatus. A horizontal loading type disc loading portion (111) is formed on the left side of the central portion of the front face of the cabinet (110). . And on the lower right side of the disc loading section (111), there is an OPEN / CLOSE key (112) for opening and closing the disc loading section,
A power (POWER) key (113) for connecting / disconnecting a power source is provided on the left side of the disc loading section (111).

Further, on the right side of the central portion of the entire surface of the cabinet (110), there is a display section (114) for making various displays described later,
Furthermore, the play (PLAY) key (11
5) and a PAUSE key (116) for pause operation are provided. And on the lower front of the cabinet (110), from the left, the numeric keys 0, 1, 2 ...
6), memory (MEMORY) key (127), memory read (M
-READ) key (128), CLEAR key (129),
Time (TIME) key (130), repeat (REPEAT) key (131), reverse (REV) key (132), fast forward (FF) key (133), down (DOWN) key (13
4), UP key (135), Auto pause (AUTO P
An AUSE key (136) and a stop (STOP) key (137) are provided.

The above-mentioned display section (114) has a data (DATA) display (114a) and a disk (DISC) display (11C) at its left end.
4b), stop (STOP) indicator (114c), pause (PAUS)
E) display device (114d), play (PLAY) display device (114e) and memory play (M-PLAY) display device (114f) are provided, and an auto pause (A-PAUSE) display device (114) is provided at the right end.
g), a total time (T-TIME) display device (114h), a re-mining time (R-TIME) display device (114i) and a repeat (REPEAT) display device (114j) are provided. A 16-channel memory indicator (ME
There is a MORY-INDICATOR (114k), a music number (MUSIC NO) display (114l) and a time (TIME) display (114m), and a pickup position display (114n) is provided to the lower left end of the display.

FIG. 3 shows an electric circuit system of the CD type disc record reproducing apparatus shown in FIG. That is, by selectively operating each of the keys (112) to (137) described above,
A disc reproducing system (20) is provided via a control circuit (201) including a microcomputer and an interface circuit.
2) is controlled to a predetermined state, and a necessary display is made by the display section (114) described above.

In the figure, the disc reproduction system (202) is recorded on the disc (206) when the disc motor (204) and the pickup feed motor (205) are driven from the control circuit (201) through the external control circuit (203). The data is reproduced by the pickup (207), and the reproduced signal is reproduced by the RF signal detection circuit (20
Send to 8). This RF signal detection circuit (208) supplies a reproduction signal to the servo circuit (209) and a demodulation circuit (210).
And the signal supplied to.

Here, the servo circuit (209) performs various focus and tracking servos for the pickup (207) and sends various signals for performing linear tracking servo to the pickup feed motor (205).

The demodulation circuit (210) separates the sync signal for address detection from the reproduced signal, supplies the sync signal to the address detector (211), and EFM demodulates the reproduced signal from which the sync signal has been separated. It is supplied to the D / A converter (212). Here, the address signal detected by the address detector (211) is RAM (2) via the control circuit (201) in the case of table-of-contents (TOC) data in the lead-in area.
In addition to being incorporated into 13), it is used to perform the necessary control functions, and if the address data (song number, elapsed time, etc.) of the program area is displayed via the control circuit (201), Be offered. In addition, the reproduction data returned to the analog signal by the D / A converter (212) drives the speaker (216) to sound while being subjected to necessary error correction, deinterleaving, error correction, and other processing. Will be offered to.

In the figure, a ROM (214) is for driving the control circuit (201) by a predetermined program, and a display section (114) is a display output control circuit for displaying various signals to be displayed by the control circuit (201). It is supplied via (215) and driven to a predetermined state.

Next, the respective keys (11
2), (115) to (137) and the function of the display unit (114) will be described.

<Open / Close (OPEN / CLOSE key (112)> If you operate this key during playback, the playback status will be canceled and the disc motor (204) will be released via the control circuit (201) and external control circuit (203). ) Is stopped, the laser diode is turned off and the pickup (207) is returned to the starting position, and then the disc loading section (111) is opened. When this key is operated, the disc loading section (111) is closed.

<PLAY (PLAY) key (115)> This key is used when used alone or in the memory read (M
-READ) key (128) or number (0-9) key (117)
There is a case where the operation is performed subsequent to the operation of (126).

First, when used alone, in the manual play mode, if the state immediately before operating this key is the pause state described later, the pause state is released and the disc motor (204), pickup feed motor (205) and The pickup (207) is activated to enter the play state. However, when the state immediately before operating this key is the play state in the memory play mode, which will be described later, the manual play mode is entered after the performance of the song is completed. In addition, if it is operated during a search operation (searching the address related to the specified song number based on the TCO data loaded in the RAM (213) and moving the pickup (207) to the position where the beginning of the song is searched for) Is set to be in a play state after the search is completed.

When used in combination with the memory read (M-READ) key (128) or the number (0-9) keys (117)-(126), the search operation state is set, and the play state is set after the search is completed. .

<Pause (PAUSE) key (116)> When this key is also used by itself and memory read (M-
READ) key (128) or number (0-9) key (117) ~
In some cases, the operation in (126) may be performed subsequently.

First, when used alone, if the state immediately before operating this key is the play state, the play state is released and the pickup feed motor (205) is stopped to enter the pause state. Further, when operated during the search operation, the pause state is set after the search is completed.

When used in combination with the memory read (M-READ) key (128) or the number (0-9) keys (117)-(126), the search operation state is entered, and the pause state is set after the search is completed. Become.

<Number (0-9) keys (117)-(126)> By operating these keys, each key
6) The reproduction music is designated in correspondence with the music number (MUSIC NO) of the data to be reproduced, that is, the track number (TNO) and the index number (X) in one music (1TNO). In addition, an operation of writing numerical key data to a memory channel is performed by using it in combination with a memory (MEMORY) key (127).

<Memory (MEMORY) key (127)> After operating the above-mentioned numbers (0-9) keys (117)-(126) or the down (DOWN) key (134) and up (UP) key (135) described later When this key is pressed, the track number specified there is stored in the control circuit (201) RAM
The memory channels (1 to 16) of (213) are written in order from the lowest numbered channel.

<Memory read (M-READ) key (128)> This key is pressed several times to move the channel displayed on the memory indicator (114k), and the contents of the written memory channel specified there are read. After that, by pressing the play (PLAY) key (115), the search operation is performed, and after the search is completed, the memory play mode is set, and the reproduction is sequentially performed according to the memory channels. When changing the contents of a memory channel, operate this key to call the memory channel you want to change and press the number (0-9) key (117) ~ (while the memory indicator (114k) of that channel is flashing. By pressing 126) and then the memory (MEMORY) key (127), the contents of the memory channel are changed.

<Clear (CLEAR) key (129)> When you press the number (0-9) keys (117) to (126) by mistake, the data is canceled and the song number (MUSIC NO) The original song number is displayed on the display (114l). The memory read (M-READ) key (12
When 8) and this key are operated at the same time, the memory all clear operation state is set.

<Time (TIME) key (130)> Each time this key is operated, the time displayed on the time display (114m) can be switched in the order of one song elapsed time (normal display), all song elapsed time, and all song remaining time. Has been done.

<REPEAT key (131)> Every time this key is operated, the repeat (repeated reproduction) of all songs or all memory channels is turned on and off.

<Reverse (REV) key (132)> While pressing this key, pick up feed motor (20
By 5), the pickup (207) is moved to the inner peripheral side in the radial direction of the disc at a high speed to perform a fast return operation.

<First forward (FF) key (133)> Pickup feed motor (20
By 5), the pickup (207) is moved to the outer peripheral side in the radial direction of the disc at a high speed to perform a quick return operation.

<DOWN key (134)> When this key is operated in manual play mode,
A search operation is performed using the address of the start portion (head) of the currently playing song as the target address, and after the search is completed, the mode state before the search is entered.

When this key is operated in the memory play mode, a search operation is performed with the target address as the address of the memory play start portion corresponding to the contents of the memory channel currently being played (song number). Enter the previous mode state.

If this key is operated during the search operation, the track number (MUSIC NO) indicator (114
For the search target TNO displayed in l), the search operation is performed with the target address being the address of the beginning of the song having the TNO immediately before it, and in the memory play mode, the song number (MUSIC NO) A search operation is performed with the target address being the address of the memory performance start portion corresponding to the memory number immediately before the music number displayed on the display (114l), that is, the content of the search target memory channel. There is.

<UP (UP) key (135)> When this key is operated in manual play mode,
A search operation is performed using the address of the start portion of the next music as the target address, and after the search is completed, the mode state before the search is entered.

When this key is operated in the memory play mode, a search operation is performed with the address of the memory play start portion corresponding to the contents of the next memory channel as the target address, and after the search is completed, the mode state before the search is resumed. .

Further, if this key is operated during the search operation, in contrast to the case of the DOWN key (134) described above, in the manual play mode, the T
A search operation is performed with the address of the start portion of the song having NO as the target address, and in the memory play mode, the address of the memory performance start portion corresponding to the memory channel content next to the search target memory channel content is targeted. A search operation using an address is performed.

<Auto pause (AUTO PAUSE) key (136)> Each time this key is operated, auto pause (automatically pauses after playing one song) is turned on and off.

<STOP (STOP) key (137)> When this key is operated, the play state is released and the disc motor (204) pickup feed motor (205) and pickup (207) are stopped after the first song search. Has become.

<DATA display (114a)> Blinks when the pickup (207) is reading the TOC data recorded in the lead-in area of the disk.
It lights up when all OC data is read normally.

<Disk (DISC) indicator (114b)> After the open / close (OPEN / CLOSE) key (112) is operated, it flashes when the disk loading section (111) is performing the opening / closing operation. Further, it is turned off when the disc loading section (111) is open, and is turned on when the disc loading section (111) is closed and the disc (206) is loaded.

<STOP indicator (114c)> It is designed to light up in the stop state.

<PAUSE indicator (114d)> It is designed to light up when in the pause state.

<Play (PLAY) indicator (114e)> It is designed to light up in the play mode.

<Memory play (M-PLAY) display (114f)> It is designed to light up in the memory play mode.

<Auto pause (A-PAUSE) display (114g)> It is designed to turn on when the auto pause function is on.

<Total time (T-TIME) display device (114h)> It lights up when the time displayed on the time (TIME) display device (114m) is the elapsed time for all songs.

<Remaining time (R-TIME) display unit (114i)> It lights up when the time displayed on the time display unit is the remaining time of all songs.

<REPEAT indicator (114j)> It is designed to light when the repeat function is on.

<Memory indicator (MEMORY-INDICATOR) (114k)
> It has 16 channels, and the part corresponding to all the written memory channels lights up. Further, in the memory play mode, the portion corresponding to the memory channel being reproduced blinks. Further, during memory writing or reading operation, the portion corresponding to the operating memory channel blinks.

<Music number (MUSIC NO) display (114l) and time (TIME) display (114m)> These consist of a total of 8 digits and are collectively referred to as the address display. That is, each two digits from the left side represent TNO (track number), X (index number), MIN (minute), and SEC (second). Where MI
N, SEC is one song elapsed time according to the operation of the TIME key (130) (starts from 00 minutes 00 seconds each time TNO changes),
All song elapsed time and all song remaining time are displayed. Further, when the disc loading section (111) is open, all are turned off, and in the reproducing state, all are turned on to display the address being reproduced.

When the number (0-9) keys (117)-(126) or memory read (M-READ) key (128) is operated, T
Only NO and X are displayed and MIN and SEC are turned off. During the search operation, TNO, X blinks and MIN, SEC goes out.

<Pickup position indicator (114n)> This shows the current playing position of the pickup (207) with respect to the disc (206). From the left side, the part corresponding to the elapsed time of all songs lights up, and the part corresponding to the remaining time of all songs is displayed. It's turned off.

Next, the program written in the ROM (214) is shown in the flowchart of FIG. When the program starts, the microcomputer in the control circuit (201) causes the interface and search function circuit in the control circuit, the external control circuit (203), the pickup feed motor (205), the RF detection circuit (208), the servo circuit ( 209),
The demodulation circuit (210) and the address detection circuit (211) cause the pickup (207) to search for a predetermined address (T1) previously stored in the ROM (214). The microcomputer moves the pickup up to N tracks ahead via the interface and the external control circuit (203) (step). Here, N is a positive integer of N ≧ 1. The amount of movement of the pickup in the radial direction (the number of tracks) can be easily performed by counting the change in the output signal of the RF detection circuit, for example. The arrival address (T ₂ ) at which the pickup actually arrived is the address detection circuit (21
It becomes readable from 1) and stored in the RAM (213) via the interface and microcomputer (step). Depending on the predetermined address (T ₁ ), the scheduled address (T _T ), the predetermined destination speed (V _T ), and the arrival address (T ₂ ) stored in the RAM (213) stored in the ROM (214) in advance, The formula is calculated to obtain the actual linear velocity (VD) of the disk record (step).

Here, this equation will be described.

Generally, the number N of tracks between a reference position (address T _X ) and an arbitrary position (address T _Y ) on a disc record is expressed by the following equation.

The reference position (address T _X ) on the disk record is located at ri from the center of the disk record, and the address (T _Y ) is located at a position advanced N tracks from this position in the outer peripheral direction. Address from the center of the disk record (T _Y )
The area on the disk record with the radius up to S, the area on the disk record with the radius from the center to the address (T _X ) is S ₁ , and the area of the area S minus the area S ₁ is S
_Set to ₂ .

The formula is derived from the above.

Here, the current position of the pickup is an address (T ₁ ) and this position is a reference position (radius r). If the pickup is moved N tracks in the outer peripheral direction of the disk record from this position, the expected address to be reached is the address (T _T ) calculated from the above table. In addition, the position where the pick-up after movement actually reaches is the address (T ₂ ), and the actual linear velocity of this disc record is V _D
Then, the following equation is obtained from the equation.

From the formula The relationship of the formula is established. That is, the actual linear velocity of the disk record can be obtained by obtaining the address ratio when the known number of tracks is moved.

Thus, the reason why the actual linear velocity of the disk record or the ratio of addresses related to the linear velocity, which has not been required until now, is obtained will be described.

For the recording linear velocity of data to the disc record,
The standard for CDs specifies 1.2 to 1.4 m / s. The recording linear velocity of commercially available discs seems to be 1.2 m / s in many cases, but there are discs other than 1.2 m / s. The recording linear velocity is determined when the disc record is manufactured, and varies depending on the manufacturer and the manufacturing apparatus. When the recording linear velocities are different for each disc record, for example, in the disc record reproducing device having the search function designed assuming that the standard recording linear velocity is 1.2 m / s, the linear velocity is 1.2 m.
When playing disc records other than / s, I realized that the search time could not be shortened to some extent even if other design efforts were made. This is because the number of times the pickup moves in the radial direction (track jump, track kick) between the start of the search and the search for the target address increases due to the difference in the linear velocity, which takes time. Therefore, by obtaining the actual linear velocity of the disc record being played or a value related to the linear velocity, high-speed and high-accuracy search operation, which was previously impossible, can be achieved, and high-speed pull-in and pickup of the CLV control system can be achieved. I thought that it would be possible to improve the accuracy of the position display.

The actual linear velocity of the disc record obtained in this embodiment is used, for example, for high speed and high accuracy of the search operation. The table of the address (performance time) stored in the ROM (214) versus the radial distance of the disk record is corrected by the actual linear velocity (step).
For example, when the UP key (135) is operated in the manual play mode, a search operation is performed using the address of the start portion of the next music as the target address. The pickup (207) is moved in the radial direction of the disk record, and the data regarding the radial distance to be moved is read from the table based on the current address. This distance is corrected by the actual linear velocity. That is, when the actual linear velocity is high (for example, 1.35 m / s), this distance is large, and when the actual linear velocity is low (for example, 1.
20m / s) is corrected so that it becomes smaller and the pickup (2
07) is moved. By doing so, the accuracy of the search operation can be improved, and high-speed search can be realized.

Furthermore, the actual linear velocity of the disc record obtained here can be used for accelerating the pull-in of the CLV control system and for indicating the position of the pickup.

Further, as described in the application specification of the original application, Japanese Patent Application No. 58-157759, the actual linear velocity is the address (performance time).
It is obtained by obtaining the ratio of. The same effect can be achieved by using this ratio. That is, the correction coefficient for obtaining the actual recording linear velocity instead of the actual linear velocity, for example, (Value related to recording linear velocity) may be used.

As described above, although the microcomputer in the control circuit is used in the embodiment of the present invention, it is obvious that each configuration can be realized only by hardware (without using the microcomputer). Further, when the present invention is realized by using a microcomputer, the flow chart is not limited to that shown in FIG. 1 and software may be assembled so that function realizing means corresponding to each requirement of the claims exists. The flow chart can be changed in various ways.

[Effects of the Invention] As described in detail above, according to the present invention, various functions of the disc record reproducing apparatus can be speeded up and increased in precision with a simple structure, and higher performance can be obtained.

[Brief description of drawings]

FIG. 1 is a flow chart showing the operation of an embodiment of the present invention, FIG. 2 is a front external view showing an embodiment of a disc record reproducing apparatus according to the present invention, and FIG. 3 is a disc record shown in FIG. It is a block diagram showing an electric circuit system of the reproducing apparatus. 201 ...... Control circuit 202 ...... Disc playback system 205 ...... Pickup feed motor 207 ...... Pickup 209 ...... Servo circuit 211 ...... Address detection circuit 213 ...... RAM 214 ...... ROM

Claims (1)

[Claims] 1. A disc record reproducing apparatus for reproducing a disc record in which a plurality of reproduction target data and their address data are digitized together and recorded at a constant linear velocity by using a pickup for reading these data. , A recording linear velocity of the data of the disc record or a value related to the recording linear velocity is obtained by using search means for moving the pickup to a desired position of the disc record and address data reproduced from the disc record. And a recording linear velocity obtained by the means or a value related to the recording linear velocity for performing the search operation of the search means.