JPS63255870A - Optical information reader - Google Patents

Abstract

PURPOSE:To retrieve an optical disk in which information is recorded with a constant linear velocity at high speed by operating an accelerating means or a decelerating means to control the rotation of the optical disk during the moving of a reproducing means and controlling the number of the rotations of the optical disk by a rotating means. CONSTITUTION:At the time of a high speed retrieval, a sliding circuit 5 is operated by a control circuit 7, a light pick-up 4 is moved and either of an accelerating switch 9 or a decelerating switch 10 is turned on. In short, for an optical disk 1, in which the information is recorded with a constant linear velocity the rotation is faster in an inner circumference and the rotation is slower in an outer circumference, therefore, when the light pick-up 4 is moved from the inner circumference of the optical disk 1 to an outer circumferential direction, the speed reducing switch 10 is turned on and when the pick-up is moved from the outer circumference to the inner circumferential direction, the accelerating switch 9 is turned on. Thus, the speed of revolution control of the optical disk at the time of the high speed retrieval can be easily executed.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an optical information reading device that requires high-speed retrieval of an optical disc or the like in which information is recorded at a constant linear velocity, and in particular, it relates to an optical information reading device that requires high-speed retrieval of an optical disc or the like in which information is recorded at a constant linear velocity. This relates to rotation control.

[Prior art] Optical discs, etc., on which information is recorded at a constant linear velocity, rotate slowly on the inner circumference and faster on the outer circumference, so in order to perform a high-speed search, it is necessary to rotate as quickly as possible according to the destination. Disk rotation must be changed.

Fig. 2 is a block diagram showing a conventional optical information reading device. ), (3) is a drive circuit that drives this spindle motor (2), (4) is an optical pickup as a reproduction means for reading information from an optical disk, and (5) is this optical pickup. A slide circuit (4) serves as a moving means for moving, for example, the optical disc (1) in the radial direction, (6) a signal processing circuit that decodes the information signal read by the optical pickup (4), and (7) a slide circuit ( 5) and a control circuit as a control means for controlling the drive circuit (3);
(8) is a rotation speed detector that detects the rotation speed of the spindle motor (2).

Next, the operation will be explained. During information reading, the signal reproduced by the optical pickup (1) is input to the signal processing circuit (6), a synchronization signal is detected, and the spindle motor (2) is kept in normal rotation through the drive circuit (3).

When searching for reading other information on the optical disc (1), the control circuit (7) operates the slide circuit (5),
The optical pickup (4) is moved in the radial direction of the optical disc (1). At that time, the number of rotations for reading information after the movement is different from before the movement, so the signal processing circuit (6
) may not be able to detect the synchronization signal or it may take time to reach normal rotation.

Therefore, the control circuit (7) calculates the number of revolutions at the destination, and transmits this calculated number of revolutions to the number of revolutions detected by the number of revolutions (8).
), outputs the difference as a voltage, rapidly accelerates or decelerates the spindle motor (2) through the drive circuit (3), and approaches the normal rotation as much as possible after movement. A signal processing circuit (6) controls the signal to reach a normal circuit.

[Problems to be Solved by the Invention] The conventional optical information reading device is configured as described above. There was a problem in that data etc. were required to calculate the number of rotations of the search destination.

This invention was made to solve the above-mentioned problems, and its purpose is to obtain an optical information reading device that can search an optical disk on which information is recorded at a constant linear velocity at high speed using a simple circuit. .

[Means for Solving the Problems] The optical information reading device according to the present invention operates the acceleration means or deceleration means for controlling the rotation of the optical disk while the reproduction means is moving, so that the number of rotations of the optical disk by the rotation means is increased. The system is equipped with a control means for controlling.

[Function] The control means of the present invention operates the acceleration means or deceleration means for controlling the rotation of the optical disc depending on the direction of movement only during the period in which the reproduction means such as the optical pickup is being moved, thereby reducing the travel time. In other words, acceleration or deceleration is performed in accordance with the moving distance, making it possible to change the rotation of the disk to near normal rotation in a short time during high-speed retrieval of an optical disk recorded at a constant linear velocity.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to FIG. 1, in which the same parts as in FIG. 2 are given the same reference numerals.

In FIG. 1, (9) is an acceleration switch as an acceleration means, (10) is a deceleration switch as a deceleration means, and (11) is a deceleration switch as a deceleration means.
) is a constant current circuit.

Next, the operation will be explained. During information reading, the signal reproduced by the optical pickup (4) is input to the signal processing circuit (6), a synchronization signal is detected, and the spindle motor (2) is kept in normal rotation through the drive circuit (3). At that time, the acceleration switch (9) and the deceleration switch (10) are kept in the OFF state by the control circuit (7).

Next, during high-speed search, the control circuit (7) operates the slide circuit (5) to move the optical pickup (4) and move the acceleration switch (9) or deceleration switch (1).
0) is turned on. In other words, an optical disc (1) on which information is recorded at a constant linear velocity rotates faster on the inner circumference and slower on the outer circumference, so the optical pickup (4) is moved from the inner circumference to the outer circumference of the optical disk (1). When moving, the deceleration switch (10) is turned on, and when moving from the outer circumference to the inner circumference, the acceleration switch (9) is turned on.

Thereby, the constant current circuit (11) connected to the acceleration switch (9) or the deceleration switch (10) is connected to the drive circuit (3) and accelerates or decelerates the rotation of the spindle motor (2).

Then, when the optical pickup (4) reaches the movement destination, the control circuit (7) stops the operation of the slide circuit (5) and stops the optical pickup (4), and the acceleration switch (9) or the deceleration switch (10) stops the operation of the optical pickup (4). ) to stop the acceleration to the spindle motor (2). Thereafter, the signal processing circuit (6) maintains normal rotation.

In the above operation, if the amount of movement of the optical pickup (4) is large, the movement time will be longer;
) will increase in rotational speed, but by performing acceleration/deceleration operations during the movement period, the rotational speed will be accelerated or decelerated in accordance with the amount of movement.

In addition, although the constant current circuit (11) was shown as a signal source for acceleration/deceleration in the said Example, there may be a fixed resistor connected to a constant voltage source.

In addition, when moving the optical pickup (4), that is, not only during high-speed search, but also when driving the optical disk (1) from a stopped state, turn on the acceleration switch (9), and when stopping the optical disk from a rotating state, turn on the deceleration switch (9). By turning on (10), starting and stopping of the optical disk (1) can be controlled in a short time.

[Effects of the Invention] As described above, according to the present invention, since the control circuit for controlling the rotation of the optical disk is configured to include the acceleration means and the deceleration means, it is easy to control the rotation speed of the optical disk during high-speed searching. can be done. Furthermore, since the rotation speed of the optical disk can be controlled by selecting either the acceleration means or the deceleration means, the apparatus can be made simple and inexpensive.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an optical information reading device according to an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional optical information reading device. In the figure, (1) is an information recording medium (optical disk), (
2) is a rotating means (spindle motor), (4) is a reproduction means (optical pickup), (5) is a moving means (fried circuit), (7) is a control means (control circuit), and (9) is an acceleration means ( (acceleration switch), (10) is a deceleration means (deceleration switch). In addition, in the figures, the same reference numerals indicate the same or corresponding parts. Agent Patent attorney Masuo Oiwa (and 2 others) Mi S Tei 11- Written amendment to the procedure for Diagram 2 of the Silkworm (spontaneous) 1. Indication of the case Patent Application No. 62-090038 2. Name of the invention Optical information reading Apparatus 3, representative of the person making the amendment Moriya Shiki 4, agent 5, column for a detailed explanation of the invention and a brief explanation of the drawings of the specification to be amended.

Claims (2)

[Claims] (1) An information recording medium on which information is recorded at a constant linear velocity, a rotating means for rotating the information recording medium, a reproducing means for reading information from the information recording medium, and a moving means for moving the reproducing means. , an accelerating means for increasing the rotation of the rotating means, a decelerating means for decreasing the rotation of the rotating means, and an operation of the accelerating means or the decelerating means during the movement of the reproducing means to reduce the rotation of the rotating means. An optical information reading device comprising a control means for controlling the number of rotations of an information recording medium. (2) Control is performed so that the acceleration means is operated when the information recording medium is rotated from a stopped state, and the deceleration means is operated when the information recording medium is stopped from being rotated. The optical information reading device according to item (1).