JPS61210526A - Information selector of disk player - Google Patents

Abstract

PURPOSE:To search speedily for a target track by detecting a radiated beam which moves radially in a disk through a moving means and a modulated beam which is modulated by hitting tracks on a disk with the radiated beam. CONSTITUTION:This device has a motor control circuit 17 which is controlled by the moving means 16 with a control signal from a signal processing circuit 12 and a tracking control circuit 18. Then, the motor control circuit 17 controls a motor 11 which moves a pickup base and the tracking control circuit 18 controls a current applied to a tracking coil 7 to move the radiated beam 2 by jumping it over tracks. Then, the radiated beam 2 radiated by a laser 3 is refracted by a mirror 5 to hit tracks of the disk 8 and modulated with infor mation on an index, etc. Consequently, ATIME at TOC need not be read before searching and a target track is searched for speedily.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Field of Industrial Application The present invention relates to an information selection device for a disc player that can quickly search for a target track and start playback.

(b) Prior Art A five-disc player, for example a digital audio disc player, which uses an optical pickup to reproduce signals from a disc on which unevenness corresponding to a digital signal is engraved, is well known. In such a digital audio disc player, a method for quickly searching for a selected target track number index is disclosed, for example, in Japanese Patent Application Laid-Open No. 5-8695.
There is a publication. In the above-mentioned Japanese Patent Laid-Open No. 55-8695, the first means selects a target address corresponding to the target track on which information is to be reproduced, and the moving means moves the incident beam relative to the medium so that the incident beam moves across the track. and a second means for monitoring the modulated beam to detect an address from information recovered by striking a medium with the incident beam while in said relatively moving search mode; detecting an index of the distance between the target track and the striking point of the incident beam during the search mode, and adjusting the moving means by the control means so as to narrow the distance between the striking point of the incident beam and the target track; It is also described that when a target track is detected, the control means stops the moving means and performs a search. In the above publication, it is stated that when the above-mentioned distance becomes narrower, the speed of movement of the means of transportation is reduced. From this, when selecting music, an index of the distance between the target track and the hitting point of the incident beam is detected, and the moving speed of the moving means is changed in stages according to the size of the distance index, and the distance between the target track and the hitting point of the incident beam is It is known that the dot does not exceed the target track and moreover quickly hits the target track.

(c) Problems to be Solved by the Invention As mentioned above, the moving speed of the moving means is gradually reduced in accordance with the size of the index of the distance between the target track and the striking point of the incident beam to quickly select a song. However, the index of the distance between the striking point of the incident beam and the target track is determined by the difference between the time from the lead intratrack to the track where the incident beam is striking and the time from the lead intratrack to the target track. This is done by detecting the difference. The time from the lead intra track to the start track of the target track is recorded and can be searched, but the time to the index track in the middle of the song is not recorded, so it is necessary to search for the index track. I can't. The present invention provides an information selection device for a disc player aimed at eliminating such drawbacks.

B) Means for Solving the Problems The information selection device for a disc player of the present invention includes a moving means controlled by a control signal obtained from a signal processing circuit, and a radiation moving means radially on the disc by the moving means. A beam detecting means detects a modulated beam that is modulated by the radiation beam hitting a track of the disk and supplies the modulated beam to the signal processing circuit.

(e) Operation Since the information selection device for a disc player of the present invention has the above-described configuration, when the radiation beam is moved to a selected target track number index and searched, if the radiation beam hits points at regular intervals. A modulated beam modulated according to the current song number index of the track on which the hit point was made is obtained. The modulated beam is detected by beam detection means and applied to a signal processing circuit. An initial control signal is generated from the signal processing circuit, and this control signal controls the means of transportation.
However, when it is determined from the index information from the modulated beam added as described above that the striking point of the radiation beam has passed through the starting track of the target index, the signal processing circuit and controlling the moving means to move the radiation beam in the opposite direction and at a slower speed towards the track of the target track number index. In this way, each time the radiation beam striking point passes the start track of the target music number index, a different control signal is generated from the signal processing circuit to reverse the movement direction of the radiation beam and gradually slow down or speed up the movement speed. . After repeating this operation a predetermined number of times, the moving search for the radiation beam is stopped.

(F) Embodiment An embodiment of the information selection device for a disc player according to the present invention will be described with reference to the drawings. (II is a pickup device, which includes a laser (3) that generates a radiation beam (2), a beam splitter (4), a mirror (51), and an objective lens (6).

A tracking coil (
7), and a photodetector α which detects the modulated beam (9) reproduced from the disk (8) and guided by the beam splitter (4) and extracts a signal, and the pickup device (1) consists of a is the pickup base (not shown)
The radiation beam (2) is moved across the tracks of the disk (8) by moving in the radial direction of the disk (8) by the motor αυ, and the tracking coil (7) The radiation beam (2) is finely moved from track to track on the disc (8) by moving the objective lens (6) horizontally to the disc (8) with a current flowing through the disc (8). α2 is a signal processing circuit that is featured in the information selection device for a disc player of the present invention, and includes at least a reading means α3 for reading information picked up by the photodetector αIK, and a reading means α3 for writing information inputted by equal pressure key operation. a writing means α4, a comparing means (lS) for comparing the information stored in the reading means αJ and the writing means α4 and generating various control signals;
It becomes more.

The αG moving means has a motor control circuit αη controlled by a control signal from the signal processing circuit (121) and a tracking control circuit, and the motor control circuit α controls the motor αυ for moving the pickup pace. .

Tracking control circuit 1) δ is the tracking coil (7
) The radiation beam (2) is moved by tracking jump by controlling the current applied to K.

Next, the operation when actually performing a search will be explained.

First, when the number of the song to be played is specified, the target song number index is written into the writing means α4 of the signal processing circuit az. Thereafter, the first control signal generated by the comparison means a5 of the signal processing circuit α2 is first applied to the motor control circuit α;
The motor αυ is rotated to slide the pickup base and move the pickup device (1) onto the disk (8). The disk (8) is also rotated by the disk motor, and the radiation beam (2) emitted from the laser (3) is passed through the mirror (5).
), is further focused by an objective lens (6), hits a track on the disk (8), is modulated by information such as an index stored there, and is reflected.

The reflected modulated beam (9; is the beam splitter (4)
The information signal such as the index of the track is picked up and read by the reading means 13 of the signal processing circuit (121). The music number index AI of the current track being recorded is read and compared with the target music number index A written in the writing means (141) by the comparing means αS (FIG. 2E).

When the track number index A of the current track is smaller than the target track number index, the radiation beam (2) is located on the inner circumference of the starting track of the target track number index, so the radiation beam (2) is directed in the first direction, which is the outer circumference direction. 2) to generate a control signal to move the radiation beam (2), and when the track number index A1 of the current track is greater than or equal to the target track number index A, K is the radiation beam (2). is located on the outer periphery of the start track of the target music number index, so the command is given to generate a control signal that causes the radiation beam (2) to move in the second direction of the inner periphery (
Figure 2G]. After the direction of movement of the radiation beam (2) is determined as described above, the motor aυ is rotated to move the radiation beam (21) at the first speed at a pick-up pace.Now the radiation beam (2) is the target. Assuming that the radiation beam (2) is located on the inner circumference of the track, the radiation beam (2) moves in the first direction at the first speed, and at this time, the track number index of the track is changed at regular intervals, for example (34 μs), as described above. Read and compare by comparison means Q51 of signal processing circuit az (second
Figure H). As a result of the comparison, while the current track number index A of the track on which the radiation beam hits at that time is smaller than the target track number index A, the radiation beam (2;) is passing through the track where the target track number index starts. The radiation beam (2) is subsequently moved in the first direction at the first speed. Index A is the target song number index A.

The identification by the comparing means α9 of the greater or the same confirms that the point of impact of the radiation beam (2) has passed through the starting track of the target song number index (FIG. 2H). Therefore, the radiation beam (2) now at a second velocity, which is slower than the first velocity.

Moreover, it is necessary to move it in a second direction opposite to the first direction. That is, after identifying by the comparing means α9 that the target song number index has become larger than the current song number index A, and that they have become the same (FIG. 2H), the radiation beam at that time (
2) to determine whether the moving speed is at the first speed (K) in FIG. 2), and when it is determined that the moving speed is at the first speed, the speed is set to the second speed (L) in FIG. Also, at this time, since the target song number index A compared by the comparing means α9 is not larger than the current song number index A1 (FIG. 2E), the moving direction of the radiation beam (2) is reversed to the second direction (the second direction). Figure 2G)
.

A second control signal satisfying the above conditions is taken out from the comparison means a9 and is then applied to the tracking coil (7)K via the tracking control circuit a&. Since the second speed moves the radiation beam (2) by jumping, for example, by 10 racks, the second control signal is a pulse signal with a width that causes the radiation beam (27) to jump by 10 racks. In this way, the radiation beam (2)
is moved 10 tracks at a time in the second direction from the outer circumference toward the inner circumference to approach the starting track of the target song number index.

During this time, the current track number index A is hit by the radiation beam (2) at regular intervals [lO tracks].
1 is read by the reading means αJ and compared by the comparing means α5.

When the comparison means α9 compares the target song number index A2 and the current song number index A is not larger, the radiation beam (2) is on the outer periphery of the starting track of the target song number index and has not yet passed through the target song number index. Therefore, the radiation beam (2) is moved 10 tracks at a time in the direction of the starting track of the target track number index (FIG. 2M). It is determined that the target song number index A2 compared with the comparison means a9 has become larger than the current song number index A (M in FIG. 2), and that the radiation beam (2) has passed through the track of the target song number index again. is identified, the direction of movement of the radiation beam (2) is reversed and the speed of movement is reduced to a third speed. To explain this according to the above and the flowchart of the aircraft, when the comparison means αS determines that the target song number index A2 is larger than the current song number index A3 (Fig. 2M), the radiation at that time is It is determined whether the moving speed of the beam (2) was the first speed (Fig. 2K), and if it was not the first speed, it is further determined whether it was the second speed (Fig. 2K).
Figure 2 N). If the moving speed of the radiation beam (2) at that time is the second speed, set it to the third speed (Figure 3 0)
At the same time, the moving direction is again reversed to the first direction (Fig. 2 G). Specifically, the radiation beam (2) is emitted from the comparison means α9.
A third control signal having a pulse width for moving the track in the first direction one track at a time is generated by the comparing means α9, and is sent to the tracking coil (71) via the tracking control circuit Ua+.
In addition, the objective lens (6) is moved and the radiation beam (2) is also moved. At this time, if you read every 10 tracks, the target index is A.

The radiation beam (
2) is within 10 tracks of the target track number index. Each time the radiation beam (2) moves one track, it is read, and the comparing means Q51 monitors when the target song number index becomes smaller than the current song number index. Radiation beam (21 movement speed was not the first speed (
(K) in Figure 2) or the second speed (N in Figure 2), and if it is determined that it is not at the first or second speed because it is at the third speed, the comparison means ttS is used. Comparatively, when the target song number index is larger than the current song number index, the generation of the third control signal is stopped and the search is stopped (see Q in FIG. 2).
. At this time, the radiation beam (2) passes through the start track of the target song number index, as described above, except when the current song number index of the track that is hit cannot be read immediately after passing the start track of the target song number index. Since it is within one or two tracks of the track, the normal tracking servo signal is sent from the comparing means α9 to the tracking control circuit Q8.
In addition to the tracking coil (7) via the tracking servo, the start of the target track number index will be reached immediately. As a result of the comparison performed by the comparing means α9 in the above, the target song number index A2 is the current song number index A.
, when K is not greater than K, the radiation beam (2) is reversed in the second direction and moves at the velocity Gλ@3 in FIG. 2 until it passes the starting track of the target song number index. Then, the radiation beam (2) passes through the track with the target song number index A, and when the target song number index becomes thicker than the current song number index, the search is stopped as described above.

In addition, in cases where the song to be selected is on a track near the outermost circumference, the reading interval of the dots of the radiation beam (2) is wide, so there is a risk that it will exceed the target track and even the outermost track. A signal identifying the end track is recorded on the track near the outermost circumference, so
When that signal is detected, the movement of the radiation beam is stopped, so the radiation beam does not skip over the outermost track and become unable to perform a search.

(G) Effects of the Invention As described above, the information selection device for a disc player of the present invention uses the comparing means to identify whether or not the current track number index on which the radiation beam hits has passed through the start track of the target track number index; Every time the radiation beam passes through the start track of the target track number index, the direction of movement of the radiation beam is reversed and the movement speed is reduced to perform a search.
There is no need to read ATIME located in Indexes that do not record the playing time up to the track cannot be searched, but
In the present invention, such indexes can also be searched.

Furthermore, since it is only necessary to identify whether or not the radiation beam has passed through the target track, the circuit configuration is simplified.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an information selection device for a disc player according to the present invention, and FIG. 2 is a flowchart showing the operation of the information selection device for a disc player according to the present invention. ... Signal processing circuit, α3... Reading means, (t4... Writing means, (151... Comparing means, ab+... Moving means.

Claims (1)

[Claims] (1) In an information reproducing device that searches for a plurality of pieces of optically readable information recorded on a disk by scanning a radiation beam along a track, the radiation beam is modulated by hitting the track, resulting in a modulated beam. beam detection means for detecting the information from the beam detection means, reading means for reading the information detected by the beam detection means, writing means for writing designated information, and information read by the reading means and written in the writing means. a signal processing circuit having a comparison means for comparing information and generating various control signals; and a moving means for moving the radiation beam controlled by the control signal generated by the signal processing circuit, and searching for the radiation beam. detecting, with the photodetector, the current track number index of the track on which the radiation beam hits the track at regular intervals;
Comparing means compares the current song number index read by the signal processing circuit with a target song number index of the song to be selected written in advance in the writing means, and the radiation beam passes through the starting track of the target song number index. Each time a different control signal is identified, the direction of movement of the radiation beam is reversed and the speed of movement is sequentially slowed down, and after this operation is repeated a predetermined number of times, the search for the radiation beam is stopped. An information selection device for a disc player, characterized in that: