JPH03185635A - optical disc device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical disc device using a separating optical system.

In order to integrate the objective lens, part of the laser, and the detection part, a separate optical system strip optical head is known in which the part of the laser and the detection part are fixed and only the actuator part is driven. It is being

[Problems to be Solved by the Invention] In the separation optical system valve optical head, where the optical system of the movable part and the optical system of the fixed part face each other, optical components are exposed in order to transmit laser light. As a result, dust tends to accumulate over a long period of time, reducing the transmittance of the laser beam and easily causing reading errors in the reproduced signal.

In order to prevent dust, it is desirable to completely seal the optical path that connects the fixed part and the movable part.However, due to the large amount of movement of the movable part and the strict requirements for the dynamic characteristics of the movable part, sealing is not recommended. It was extremely difficult.

[Means for Solving the Problems] In view of the above problems, it is an object of the present invention to provide an optical disc device that reduces the adhesion of dust to optical components and does not cause reading errors in reproduction signals. .

The above object is achieved in an optical disk device having a separate optical system optical head, in which the movable head section substantially fits into the fixed head section near the optical path at its home position when not in operation.

[Function] In the present invention, the optical disc device is capable of retracting the movable head portion to a predetermined home position when not in operation when recording, reproducing, or erasing operations are performed;
Focusing on the fact that the non-operating time is longer under normal optical disk device usage conditions, we have reduced the adhesion of dust to the movable head and fixed head parts when the movable head is set at the home position. This made it possible to prevent errors in reading the reproduced signal.

[Example J] The present invention will be described in detail with reference to the figures. 1 and 2 show an embodiment of the present invention, showing a spindle motor of an optical disk and a base portion including a head portion. Figure 1 shows ho.
- FIG. 2 shows a state in which the movable head has moved to the inner circumference of the disk for recording and reproduction.

1 is a base, 2 is a spindle motor that rotates the disk, 3 is a servo circuit for the spindle motor, 4.6 is a linear motor for coarse movement of the head 5.7 is its coil part, and is fixed to the movable head part 8. ing.

Reference numeral 8 includes at least an objective lens 8a, a cylindrical protrusion 11a, which will be described later, provided in an opening for inputting and outputting a laser beam from or to the fixed head of the objective head 8, and a home. It is a cylindrical projection that surrounds the laser beam path that fits in the position.

11 is a fixed head part, and the optical path to the movable head part, that is, the opening for inputting and outputting laser light, is provided with a cylindrical protrusion 11a that surrounds the optical path; e 12a and b are photointerrupters; A control circuit (not shown) detects that the movable head is not in operation, and when the movable head is moved back to the home position C, it determines whether the movable head has reached the home position. It is something to detect. The control circuit stops the movement upon this detection, and when the strip 4 or the protrusion 8b is fitted with the protrusion 11a, the protrusion 8
The shape of the fixed head part and the fixed head parts 8b and 11a is not limited to a cylindrical shape, and the optical path method is used to prevent them from rubbing against each other and damaging other optical components etc. when mated at the home position. It is desirable to design the diameter and length of the droplet cylinder in advance.

Next, the operation in the embodiment of the present invention will be explained based on FIGS. 1 and 2. Figure 2 shows that during normal recording and playback,
This is a diagram showing when the movable head part is located on the inner circumferential side, and the part 8b through which the laser beam enters from the fixed head part and the part lla of the fixed head part are exposed, and the internal optical parts (cover glass) are exposed. (including) that dust tends to adhere to it.

However, as shown in FIG. 1, when the device returns to its home position during non-operation, lla and 8b are nearly fitted, making it difficult for dust to adhere.

[Effects of the Invention] According to the present invention, in an optical disk device using a separation optical system and a torrent optical head, when the movable head section is at its home position, the movable head section and the fixed head section are connected to each other in the direction of the laser beam. By configuring the optical path portion to fit snugly, dust is prevented from adhering.

Further, by having this cylindrical fitting portion, there is an effect that dust is less likely to adhere to the optical components even when there is no movable head portion at the home position.

Note that the term "fitting" as used in this specification does not mean that two objects are completely fixed to each other so that they cannot move relative to each other, but rather, if necessary, without rubbing against each other. It shows a state where it is fixed to the extent that it can be moved relatively.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the optical disc device of the present invention when it is not in operation. FIG. 2 is a diagram showing the optical disc device of the invention when it is in operation. l...Base 8...Movable head section 8b...Protrusion 11...Fixed head part 11a...Protrusion

Claims (1)

[Claims] In an optical disc device having an optical head separated into a movable head part that moves in the radial direction of the disc and a fixed head part, when the movable head part is at its home position, the movable head part An optical disk device characterized in that a fixed head portion is substantially fitted in the vicinity of an optical path.