JPH0521328U - Optical disk device - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide an optical disk device for a specific application, which has a simplified mechanism and is downsized. In the optical disc device 1, the track feed mechanism of the optical pickup 7 is omitted, and the optical pickup 7 is held at a fixed position 9a by a first guide bar 8 and a second guide bar 9, and the objective is held. The tracking servo mechanism of the lens 6 is used to follow each track 4a, 4b, 4c.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an optical disc apparatus for optically detecting and reproducing an information signal.

[0002]

[Prior Art]

 Conventionally, generally known optical disk devices have a means for irradiating a disk surface on which an information signal is recorded with laser light by an optical pickup, and detecting and reproducing the information signal by the reflected light. ing.

At this time, the optical pickup is provided with a tracking servo mechanism of an objective lens that follows a minute section and a pick-up feed mechanism that covers a range that cannot be tracked by a tracking servo. It is configured to read the information signal.

[0004]

[Problems to be solved by the device]

 However, in the above-mentioned conventional optical disk device, since the servo mechanism and the feed mechanism of the pickup are required, the drive motor required for the circuit configuration and the feed mechanism and the feed mechanism parts and many parts are required. However, if it is only necessary to reproduce an optical disc with a small amount of information, it will have an unnecessarily large number of configurations, and if an optical disc is used for a specific purpose, the optical disc device will be more expensive and will be provided at low cost. There was a problem that it could not be done.

The present invention has been devised in view of the above problems, and an object thereof is to provide an inexpensive optical disk device for a specific purpose with a small amount of information signals.

[0006]

[Means for Solving the Problems]

 Therefore, as a means for solving the above-mentioned problems, the present invention is an optical disc apparatus, in which the feed mechanism of the optical pickup of the optical disc apparatus is omitted, and the optical pickup is held at a fixed position so that the objective lens of the optical pickup is The optical disk device is configured so that it can reproduce only the information signal in the range that can be covered only by the tracking servo.

[0007]

[Action]

 Since the optical pickup of the optical disc device is fixed and the feeding mechanism is omitted, the optical disc device for a specific application can be provided at a low cost with a simple structure.

[0008]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic plan view showing an embodiment of an optical disc device according to the present invention, and FIG. 2 is used for an optical disc device according to the present invention. FIG. 3 is a plan view of an optical disc according to the present invention.

As shown in the figure, an optical disk device 1 according to the present invention comprises a frame 3 arranged in a case body 2, a spindle motor 5 for rotating and driving an optical disk 4, an objective lens 6 and a tracking servo mechanism thereof. Optical pickup 7, a first guide bar 8 for slidably supporting one end of the optical pickup 7, and a first guide bar 8 for supporting the other end of the optical pickup 7 at a plurality of fixed positions. It comprises two guide bars 9 and a positioning lever 10 for selectively moving the optical pickup 7 to a predetermined position.

Further, the positioning of the optical pickup 7 will be described in detail. As an example, the optical pickup 7 includes a pickup housing 7a and a leaf spring 11 having a positioning protrusion 11a arranged on the pickup housing 7a. The second guide bar 9 has a structure in which the second guide bar 9 is positioned so as to be sandwiched by the biasing force of the leaf spring 11, and the positioning protrusion 11a of the leaf spring 11 is fitted on the upper surface of the second guide bar 9. A plurality of concave portions 9a are provided.

Here, as the positions of the concave portions 9a, for example, a concave portion 9a for positioning the optical pickup 7 on the innermost track portion 4a of the optical disc 4 shown in FIG. 2 and a concave portion 9a for positioning on the central track portion 4b are shown. , And recesses 9a for positioning on the outermost track portion 4c.

Next, the positioning operation state of the optical pickup 7 will be described. When the positioning lever 10 is slid in the arrow direction against the urging force of the leaf spring 11, the positioning protrusion 11a provided on the leaf spring 11 is moved. Comes out of the fitting with the recess 9a and slides on the upper surface of the second guide bar 9 and fits in the next positioning recess 9a so that the optical pickup 7 is brought into a fixed position corresponding to a predetermined track. It is positioned and fixed, and the specific track portions 4a, 4b, 4c of the corresponding optical disk 4 are reproduced at this fixed position.

Next, the data capacity and the like of the optical disk 4 used in the optical disk apparatus 1 according to the present invention will be described. With respect to the pickup capacity of the currently common optical disk apparatus, there is no pickup feeding mechanism, that is, the pickup capacity. The range in which the track on the optical disk 4 can be followed only by servo tracking of the objective lens is about ± 500 μmm, and in actual driving, the range of ± 200 μmm is the range that can be followed in consideration of vibration resistance. There is.

Here, in order to determine the recording band of the optical disc 4, strictly speaking, it is necessary to consider the error when the optical disc 4 is mounted and the eccentricity of the optical disc 4 itself. The data capacity that can be recorded in the upper recording band of 400 μmm is calculated and shown in Table 1 of FIG.

Next, FIG. 4 is a diagram showing which position on the optical disc 4 each recording band portion on the optical disc 4 corresponds to. In FIG. 4, (1) is the innermost track portion 4 a, (2) shows the position of the central track portion 4b, and (3) shows the position of the outermost track portion 4c.

There are 250 tracks in each track portion 4a, 4b, 4c in the optical disk device 1 according to the present invention, and all the tracks in the track portions 4a, 4b, 4c are optically picked up. The time required for 7 to jump is 500 mSEC because 2 mSEC is required for one track jump.

[0017]

[Effect of the device]

 Therefore, according to the above-mentioned optical disk device of the present invention, the feeding mechanism of the optical pickup is omitted and only the specific recording band portion on the optical disk is reproduced. It is possible to provide an optical disc device as an optical disc reproducing device in a field at a low cost, and it is possible to easily reduce the size of the optical disc device due to the simple mechanism.

[Brief description of drawings]

FIG. 1 is a schematic plan view showing an embodiment of an optical disk device according to the present invention.

FIG. 2 is a plan view showing a recording band of an optical disc used in the optical disc device according to the present invention.

FIG. 3 is a table showing a data capacity of an optical disc according to the present invention.

FIG. 4 is a view showing a position of a recording band of the optical disc according to the present invention.

[Explanation of symbols]

 1 Optical Disk Device 2 Case Body 3 Frame 4 Optical Disk 4a Innermost Track Section 4b Center Track Section 4c Outermost Track Section 5 Spindle Motor 6 Objective Lens 7 Optical Pickup 7a Pickup Housing 8 First Guide Bar 9 Second Guide bar 9a Fitting recess 10 Lever 11 Leaf spring 11a Positioning protrusion

Claims (1)

[Scope of utility model registration request] 1. An optical disc device for detecting an information signal recorded on a rotating disc surface by an optical pickup, wherein the pickup holds the pickup at a fixed position.