JPS63220487A - Compact disk player - Google Patents

Abstract

PURPOSE:To rapidly and accurately move an optical pickup, by providing an optical pickup position detecting part, an optical pickup driving part which moves the optical pickup, a control part which outputs a control signal to make the optical pickup driving part change travel speed, and a timer part which counts a time based on indication from the control part. CONSTITUTION:The optical pickup position detecting part 11 which detects the position of the optical pickup of a compact disk player, the optical pickup driving part 12 which moves the optical pickup, the control part 13 which outputs the control signal to make the optical pickup driving part 12 change the travel speed, and the timer part 14 which counts the time by the indication from the control part 13, are provided. And when the instruction to move the optical pickup is issued, it is moved at the maximum acceleration to an intermediate point to a targeted point, and the travel speed during that section is measured. In such a way, since the pickup can be moved efficiently in a decelerating section from the intermediate point to the targeted point, it is possible to move the optical pickup rapidly and accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a compact disc player capable of quickly moving an optical pickup to a designated location 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. 4 is a block diagram of a conventional compact disc player, in which 21 is an optical pickup position detection unit that detects the position of the optical pickup of the compact disc player, 22 is a control unit that outputs information on the target point to which the optical pickup should move;
23 is a comparison unit that compares the information from the optical pickup position detection unit 21 and the information from the control unit 22 and produces an error; 24 is a unit that reduces the error according to the magnitude of the error information from the comparison unit 23; This is an optical pickup drive unit that moves the optical pickup.

Regarding the compact disc player configured as described above, the operation of each part of the compact disc player when the optical pickup is moved will be described below.

When the point to which the optical pickup should be moved is instructed, the control unit 2
2 outputs information corresponding to the point to be moved, the optical pickup position detection section 21 outputs information on the current position of the optical pickup, and the information from the control section 22 and the information from the optical pickup position detection section Z are output. A comparison section 23 compares the results. The error information written as a result is transmitted to the optical pickup driving section 24, and the optical pickup is moved in a direction where the error is reduced by a driving force proportional to the magnitude of the error information.

Problems to be Solved by the Invention However, in the above configuration, the optical pickup is moved only based on the error information from the control section 22 and the information from the optical pickup position detection section 21, so the efficiency in moving the optical pickup is low. Unable to accelerate or decelerate.

Therefore, there was a problem in that it took time to move the optical pickup.

The present invention has been made in view of the above problems and provides a compact disc player that allows the optical pickup to be moved quickly when an instruction to move the optical pickup is received.

Means for Solving the Problems In order to solve the above problems, the compact disc player of the present invention includes an optical pickup position detection section for detecting the position of the optical pickup, an optical pickup drive section for moving the optical pickup, and an optical pickup position detecting section for detecting the position of the optical pickup. This device includes a control section that outputs a control signal for changing the moving speed to the pickup drive section, and a timer section that measures time based on instructions from the control section.

Effects of the present invention With the above-described configuration, when an instruction to move the optical pickup is received, by knowing the position and time of movement of the optical pickup while it is moving, efficient driving force can be generated when moving the optical pickup, and the optical pickup can be moved quickly. It becomes possible.

EXAMPLE Hereinafter, a compact disc player according to an example 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
1 is an optical pickup position detection unit that detects the position of the optical pickup of the compact disc player; 12 is an optical pickup drive unit that moves the optical pickup; and 13 is a control unit that outputs a control signal to change the moving speed of the optical pickup drive unit 12. Section 14 is a timer section that measures time according to instructions from the control section 13.

The compact disc player of this embodiment configured as described above will be explained using the flowchart of FIG. 2 and the graph of FIG. 3.

First, when the point to which the optical pickup should be moved is instructed, the control section 13 instructs the timer section 14 to start time measurement as in step 1, and the optical pickup drive section 12 is instructed to move the optical pickup at maximum acceleration. Give instructions. Then, as in step 2, when information is obtained from the optical pickup position detecting section 11 that the optical pickup has reached the midpoint of the distance to be moved to the destination point, as in step 3, the movement measured by the timer section 14 is performed. The travel time from the starting point to the intermediate point is stored in the control section 13, and as in step 4, the average speed of the optical pickup during the accelerated movement is determined by the control section 13 from the time and the travel distance. Assuming that the travel time is t, we can draw an average speed line from the starting point to the halfway point as shown in Figure 4, and by extending that line, we can see that the traveling speed of the optical pickup at the halfway point is saturated. If the acceleration and deceleration are the same, it is estimated that if the optical pickup is decelerated to the maximum from the intermediate point, it will reach the destination point at a speed of 0 in a travel time of 2t. Therefore, the process moves to step 6, and the control section 13 issues an instruction to the timer section 14 to start time measurement, and a control signal to the optical pickup drive section 12 to perform maximum deceleration movement. Note that steps 3 to 5 are performed almost simultaneously. During the deceleration movement of the optical pickup as in step 6, the control section 13 monitors the position of the optical pickup using information from the optical pickup position detection section 11 and the movement time using information from the timer section 14. In step 7, the control signal for the deceleration force to the optical pickup drive unit 12 is adjusted from the control unit 13 so as to approach the average speed line obtained in step 4, so that the speed becomes zero at the destination point of the optical pickup. Then, as shown in step 8, if the optical pickup has not yet reached the destination point based on the information from the optical pickup position detection section 11, the process repeats from step 6, and if the destination point is reached, the process proceeds to step 9 to stop the optical pickup movement.

As described above, according to this embodiment, when an instruction to move the optical pickup is received, the optical pickup moves at maximum acceleration to the intermediate point leading to the destination point, and by measuring the travel time during that time, the optical pickup is decelerated from the intermediate point to the destination point. Since the optical pickup can be moved efficiently between sections, it is possible to move the optical pickup quickly and accurately.

Effects of the Invention As described above, the present invention includes an optical pickup position detection section that detects the position of the optical pickup, an optical pickup drive section that moves the optical pickup, and a control signal that changes the moving speed of the optical pickup drive section. By providing a control section that outputs an output and a timer section that measures time according to instructions from the control section, the optical pickup can be moved quickly and accurately.

[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 flowchart of the operation according to an embodiment of the present invention, and FIG. 3 is a diagram showing the moving distance of an optical pickup according to an embodiment of the present invention. FIG. 4, a graph showing the relationship over time, is a block diagram of a conventional compact disc player. 11... Optical pickup position detection section, 12...
. . . Optical pickup drive section, 13 . . . Control section, 14 . . . Timer section. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2

Claims (1)

[Claims] An optical pickup position detection unit that detects the position of the optical pickup that reads data from a compact disc as it moves, an optical pickup drive unit that moves the optical pickup, and outputs a control signal that changes the moving speed to the optical pickup drive unit. What is claimed is: 1. A compact disc player comprising: a control section that measures time; and a timer section that measures time according to instructions from the control section.