JPS63206955A - Compact disk player - Google Patents

Abstract

PURPOSE:To shorten the time needed for acquisition of the synchronism after the end of the shift of an optical pickup by approximating the disk rotational frequency to the estimated rotational frequency of an access receiver while the optical pickup is moving at the time of a high-speed access. CONSTITUTION:A control part 14 calculates the disk rotational frequency of an access receiver and compares it with the present rotational frequency obtained from a rotational frequency detecting part 13. Then an acceleration or deceleration control signal is delivered a spindle motor driving part 15 so that the coincidence is obtained from said comparison. These control signals are delivered continuously to the part 15 until the shift of an optical pickup is finished at an indicated point so that the present rotational frequency is equal to that calculated by the part 14. Thus the disk rotational frequency can be approximated to the normal level of the access receiver before the shift of the optical pickup is through. As a result, it is possible to shorten the time needed for acquisition of the synchronism after the end of the shift of the optical pickup in a high-speed access state.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a compact disc player that can quickly retrieve data on a compact disc.

BACKGROUND OF THE INVENTION In recent years, compact disc players have attracted attention for their good operability, including random access.

An example of the above-mentioned conventional compact disc player will be described below with reference to the drawings.

FIG. 3 is a configuration diagram of a conventional compact disc player, in which 21 is a signal detection unit that extracts signals on the compact disc, 23 is a spindle motor drive unit that rotates the disc, and 22 is a signal from the signal detection unit 21 and a reference. This is a spindle servo unit that outputs control signals to the spindle motor drive unit 23 so that signals can be synchronized.

The operation of the compact disc player configured as described above during access will be described below.

When an access instruction is issued in a compact disc player, since the compact disc records data at a constant linear velocity, the wavelength of the signal obtained from the signal detection unit 21 changes as the optical pickup moves. The spindle servo unit 22 outputs a control signal to the spindle motor drive unit 23 to speed up or slow down the rotation of the disk so that the signal and the reference signal can be synchronized.

Problems to be Solved by the Invention However, with the above configuration, when the optical pickup moves at high speed, the signal detecting section 21 cannot obtain a signal that can be compared with the reference signal in the spindle servo section 22 during the movement. This has the problem that synchronization is required after the optical pickup has finished moving, resulting in time loss during high-speed access.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention provides a compact disc player that reduces the time required to synchronize after the optical pickup has finished moving during high-speed access.

Means for Solving the Problems In order to solve the above problems, the compact disc player of the present invention includes a signal detection unit that detects signals recorded on a compact disc, and a signal detected by the signal detection unit and a reference. a spindle servo unit that compares the signals and outputs a control signal to fully accelerate or decelerate the rotation of the disk;
A device comprising a rotation speed detection section that detects the rotation speed of the disk, a spindle motor drive section that rotates the disk, and a control section that outputs a control signal to the spindle motor drive section based on information from the spindle servo section 9 rotation speed detection section. It is.

Effect of the Invention With the above-described configuration, the present invention reduces the time required for synchronization after the optical pickup has finished moving by keeping the rotational speed of the disk close to the expected rotational speed of the access destination while the optical pickup is moving during high-speed access. I will do it.

Embodiment Hereinafter, a compact disc player according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a block diagram of a compact disc player according to an embodiment of the present invention. In Figure 1, 1
Reference numeral 1 denotes a signal detection section that extracts signals on the compact disc; 12 indicates a spindle servo section that outputs a control signal to synchronize the signal from the signal detection section 11 with the reference signal; and 13
15 is a spindle motor drive unit that rotates the disk °; 14 is a spindle motor drive unit 16 using a control signal from the spindle servo unit 12 and information from the rotation speed detection unit 13; This is a control section that outputs control signals to.

The operation of the compact disc player of this embodiment constructed as described above will be explained below using the flowcharts shown in FIGS. 1 and 2.

When an access instruction is given in the compact disc player, the control unit 14 calculates the number of rotations of the disc at the access destination as in step 1. Then, the process moves to step 2 and outputs an acceleration or deceleration control signal to the spindle motor drive section 15 so that the current rotation speed obtained from the rotation speed detection section 13 is compared with the calculated rotation speed. Then, as in step 3, until the movement of the optical pickup to the instructed point is completed, the controller 14 continues to output an acceleration or deceleration control signal to the spindle motor drive unit 16 so as to achieve the calculated rotational speed, When the optical pickup finishes moving, the signal on the compact disc obtained from the signal detection section 11 is sent to the spindle servo section 1 as in step 4.
2, the information obtained from the spindle servo unit 12 is outputted from the control unit 14 to the spindle motor drive unit 15 to normalize the rotation by comparing it with a reference signal and ensuring synchronization.

As described above, according to this embodiment, during high-speed access in a compact disc player, the control unit calculates the number of revolutions of the accessed disc at the start of access, and the number of revolutions detecting unit is installed to monitor the number of revolutions of the disc. By making this possible, you can keep the disk rotation speed close to the normal rotation speed at the access destination by the time the optical pickup finishes moving. By synchronizing after the optical pickup finishes moving during high-speed access, The time required for this can be reduced.

Effects of the Invention As described above, the present invention includes a signal detection unit that detects a signal recorded on a compact disc, and a signal extracted by the signal detection unit that is compared with a reference signal to accelerate or decelerate the rotation of the disc. A spindle servo section that outputs a control signal, a rotation speed detection section that detects the rotation speed of the disk, a spindle motor drive section that rotates the disk, and a spindle servo section that outputs a control signal to the spindle motor drive section based on information from the rotation speed detection section. By being equipped with a control unit, when accessing the compact disc player at high speed,
The time required by synchronizing the optical pickup after it has finished moving can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a compact disc player according to an embodiment of the present invention, FIG. 2 is a 70-chart of operation in an embodiment of the present invention, and FIG. 3 is a block diagram of a conventional compact disc player. 11... Signal detection section, 12... Spindle servo section, 13... Rotation speed detection section, 14.
...control section, 15... spindle motor drive section. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 4 1 frame where Suku appears = Tsuyo 3 Figure ν Mo Hatsune! Report section 71al Guichi Nuchifugu 4 ]

Claims (1)

[Claims] A signal detection unit that detects the signal recorded on the compact disc, a spindle servo unit that compares the signal extracted by the signal detection unit with a reference signal and outputs a control signal to accelerate or decelerate the rotation of the disc, and a spindle servo unit that outputs a control signal to accelerate or decelerate the rotation of the disc. It is characterized by comprising a rotation speed detection section that detects the rotation speed, a spindle motor drive section that rotates the disk, a spindle servo section, and a control section that outputs a control signal to the spindle motor drive section based on information from the rotation speed detection section. compact disc player.