JPH02192037A - Optical recording/reproducing device - Google Patents

Abstract

PURPOSE:To promptly and correctly move an optical head to a prescribed position by directly moving an optical head itself in the track direction of an optical recording medium. CONSTITUTION:Electromagnetic force is operated for a driving coil 21 by conducting the driving coil 21 wound around a floating main body 22, and the floating main body 22 itself is reciprocatively moving-operated along the track direction of an optical recording medium 1 by the electromagnetic force. That is, since the floating main body 22 itself constituting an optical head 2 is directly moving-driven in the track direction of the optical recording medium 1, the optical head 2 and the driving source of the driving coil 21, etc., to drive the head 2 are integrated, and the generation of moment force at the time of moving the optical head 2 can be prevented. Thus since an oscillating characteristic is improved and a track driving control is stabilized, the optical head 2 can be promptly and correctly moving-operated to the prescribed position.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to an optical recording and reproducing device that records and reproduces information, or records, reproduces, and erases information using an optical recording medium such as an optical disk. In particular, the optical head can be operated at high speed and
This invention relates to an improvement in an optical recording/reproducing device that can be moved accurately.

[Prior Art] As shown in FIG. 4, this type of optical recording/reproducing device includes a semiconductor laser (a) and a collimator lens that converts the diffused laser light from the semiconductor laser (a) into parallel laser light. (b), a beam shaping prism (C) that converts the spot shape of this laser light from an elliptical shape to a substantially circular shape, and the incident laser light that enters the optical recording medium (d) and the reflected light from the optical recording medium (d). a beam splitter (e) that separates the incoming reflected laser beam, and this beam splitter (e).
a 174 wavelength plate (f) that passes through the 174 wavelength plate (f) and converts linearly polarized laser light into circularly polarized light;
An objective lens (CI) that converges the laser beam that has passed through the wavelength plate (f) onto the convergence surface of the optical recording medium (d), and a tracking error signal and a focusing signal for the reflected laser beam that is separated by the beam splitter (e). A device is known in which the main part thereof is composed of a cylindrical lens (j) that makes the error signal and a reproduced RF signal enter a four-division PIN photodiode (h).

In such an optical recording/reproducing device, an objective lens (q) or the like is used to record information in a spiral shape or concentrically on the surface of the optical recording medium (d), or to reproduce recorded information. While moving the optical head including the optical system along the track direction of the optical recording medium (d),
In order to cope with surface wobbling of the optical recording medium (d), it is necessary to move the optical head in the focus direction, and conventionally, the following drive system has been used.

First, as an example, as shown in FIGS. 5 and 6, a drive coil (p
A moving table (k) with an H-shaped cross section on which an optical head (He) equipped with an optical head (He) is mounted so as to be movable in the track direction and the focusing direction; A carriage (m) and a linear bearing (n>) for movably supporting the moving table (k), and a pair of bobbins (Ql) attached to both sides of the moving table (k) and around which a driving coil (p2) is wound. ) (Q2) and these bobbins (ql
) (q2), a pair of magnetic yokes (rl
)(r2) and track control permanent magnets (Sl) to (S
4) and this track control permanent magnet (sl) (s
4) Permanent magnets for focus control (s5) (s6) arranged in the length direction, and these permanent magnets (Sl
) to (S6), and the main part thereof is composed of a magnetic holder (1) that holds the optical head (He).
optical head (lee) using electromagnetic force acting on the
Focus control is performed by moving the bobbin (rl) (
When the drive coil (p2) of r2) is energized, the moving platform (
k) in the six directions of arrows, and the optical head (He) mounted on this moving table (k) was moved back and forth along the track direction of the optical recording medium (d).

On the other hand, as another example, as shown in FIG. 7, an optical helad (He) placed near the optical recording medium (d) and floating by the air flow accompanying the rotation of the optical recording medium (d), A spring-like suspension (V) that supports the optical head (He) so as to be able to advance and retreat with respect to the optical recording medium (d), and a voice coil motor (V) that holds the base end side of this suspension (V).
The main part thereof is composed of a moving member (y) that is linearly moved in the track direction of the optical recording medium (d) by W), and a drive coil (Z) wound around this moving member (y).
When the moving member (y) is energized, the moving member (y) is moved to move the optical head (He) toward the tracker of the optical recording medium (d), and the air flow acting on the optical head (He) moves the optical head (He). ) was moved in the focus direction of the optical recording medium (d) to perform focus control.

[Problem to be Solved by the Invention 1] By the way, in the former optical recording/reproducing device incorporating the above-mentioned drive system, focusing is performed using electromagnetic force acting on the drive coil (pl) of the optical head (lle). There is a problem that the control system is complicated due to the configuration that performs control, and furthermore, as shown in Fig. 6, the optical head (He) is
), carriage (m), bobbin (Ql) (Q2)
, magnetic yoke (rl) (r2), permanent magnet (sl)
- (S4) etc., there is a drawback that moment force is applied to this optical head (He) when the optical head (l18) moves, and the drive source (x) There is a problem in that the control becomes unstable and the optical head (He) cannot be moved quickly and reliably to a predetermined position.

On the other hand, the latter optical recording/reproducing device has the advantage of simplifying the control system because it is configured to perform focus control using airflow acting on the optical head (He). is installed via a spring-like suspension (V) at a position away from the drive source (X) consisting of a voice coil motor (W), a moving member (y), etc., so the optical There is a drawback that a moment force is applied to the optical head (He) when the head (He) is moved, and there is a problem in that the optical head (He) cannot be moved quickly and accurately to a predetermined position.

[Means for Solving the Problems] The present invention has been made in view of the above problems, and its object is to quickly and accurately move an optical head back and forth in the track direction of an optical recording medium. An object of the present invention is to provide an optical recording/reproducing device that can be moved and operated.

That is, the present invention provides a reflecting member that is placed near a rotating optical recording medium, floats due to the air flow accompanying the rotation of the optical recording medium, and reflects focused light from a light source toward the optical recording medium, and this reflecting member. an optical head equipped with an objective lens that converges reflected focused light onto a convergence surface of an optical recording medium, and around which a driving lens is wound; and an optical head that is moved in the floating direction and in the track direction of the optical recording medium A support member movably supports the optical recording medium, and a magnet that is provided along the track direction of the optical recording medium and forms lines of magnetic force toward the optical head. This is characterized in that the optical recording medium is moved in the track direction of the medium.

In such technical means, the optical head floats in response to the air flow accompanying the rotation of the optical recording medium, and in order to efficiently receive the floating pressure from the optical recording medium, at least the bottom portion of the optical head is A sliding surface and an air introduction surface are formed on the sides. Further, for the purpose of stabilizing the floating movement of the optical head, a groove for letting air escape along the length of the head, that is, a central relief part may be formed.

In this case, the number and shape of the grooves can be arbitrarily set depending on the purpose. In addition, the material constituting this optical head is preferably a hard material that is lightweight, has good processing accuracy, and is hard to scratch.Specifically, ceramic materials, amorphous carbon, barium titanate, and titanate Potassium etc. can be used. However, when a conductive material such as amorphous carbon is used, it is necessary to apply no insulation treatment such as coating an insulating film on at least the portion around which the drive coil is wound.

Further, the method of mounting reflective members such as mirrors and prisms and objective lenses on this optical head is arbitrary. For example, this optical head may be constructed from a single floating member and a drive coil may be wound around a part of the optical head. Alternatively, the optical head may be constructed of two members, at least one of which is capable of floating, and a driving coil may be wound around one of the members while the other may be rotated. A method of incorporating an objective lens or the like may also be adopted. In this case, in order to suppress the generation of moment force during movement, it is necessary to attach both members so that they can be moved on the same plane.

On the other hand, regarding the support member that supports the optical head,
Any structure can be used as long as the optical head is movably supported in the floating direction and in the track direction of the optical recording medium. This can be constituted by an elastic member such as a spring spring that is disposed between the movable body and the optical head and connects these members to each other.

In addition, the magnets that form the lines of magnetic force toward the optical head are composed of permanent magnets such as rare earth iron magnets, electromagnets, etc., and are arranged along the track direction of the optical recording medium, and are wound around the optical head. By energizing the drive coil, an electromagnetic force is applied to the drive coil, and this electromagnetic force moves the optical head in the track direction of the optical recording medium.

[Operation] According to the above-mentioned technical means, the optical head itself is directly moved in the track direction of the optical recording medium by the electromagnetic force accompanying the energization of the driving coil wound around the optical head. The optical head and the drive source are integrated, making it possible to prevent the generation of moment force during movement.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

That is, as shown in FIGS. 1 to 3, this optical recording/reproducing device includes an optical head (2) placed near an optical recording medium (1), and an optical head (2) that connects the optical head (2) to the optical recording medium. (
A support member (3) that supports the optical recording medium (1) movably in the focus direction and the track direction, and a pair of permanent magnets (1) arranged parallel to each other along the track direction of the optical recording medium (1).
The main parts are composed of 40) and 41.

First, the optical head (2) is a floating body made of ceramic material, with a driving coil (21) wound around its central four parts (20), and an air introduction surface and a sliding surface formed on the bottom side. (22), and a prism (2) attached to the center side of the optical recording medium (1) of this floating body (22).
3) and an attached main body (25) equipped with an objective lens (24).
).

On the other hand, the support member (3) is provided along the track direction of the optical recording medium (1) and has an engagement groove (30) on the opposite side.
A pair of guide members (32) (33) formed with (31)
), and the guide members (32) (33) are disposed between these guide members (32) (33) and on both sides of the guide members (32) (33).
a movable body (37) formed of a lightweight aluminum alloy material and having engaging portions (35) (36) that engage with the engaging grooves (30) (31) of the movable body through bearings (34); This moving body (37) and the floating body (2
2) It is composed of six spring members (38) to (38) interposed between them and connecting these members to each other.

The permanent magnets (40) and (41) are band-shaped rare earth iron-based magnets attached to holding members (42) and (43) arranged in parallel to the guide members (32 and 33) in the support member (3). It is composed of permanent magnets, and these permanent magnets (40) (41) connect the floating body (2
2) Lines of magnetic force moving toward the side are formed.

In the optical recording/reproducing device configured in this way,
Laser light from a light source (not shown) provided on the device main body side is incident on the prism (23) of the optical head (2),
The laser beam reflected by the prism (23) t' is focused on the converging surface of the optical recording medium (1) by the objective lens (24), thereby recording, reproducing, and erasing information.

In this device, a drive coil (21) is wound around the floating body (22) via a lead wire (not shown).
When energized, an electromagnetic force acts on this driving coil (21), and this electromagnetic force causes the floating body (22) itself to reciprocate along the track direction of the optical recording medium (1), while the above-mentioned The floating body (22) floats due to the air flow acting on the floating body (22), and the distance between the optical recording medium (1) and the floating body (22), that is, the optical head (2) is maintained constant and focused. It is something that is controlled.

In this way, in this optical recording/reproducing device, the floating body (22) constituting the optical head (2) itself is moved directly in the track direction of the optical recording medium (1), so that the optical head (2) and The drive coil (21
) etc., and it is possible to prevent the generation of moment force during movement of the optical head (2).

Therefore, since the vibration characteristics are improved and the track drive control is stabilized, there is an advantage that the optical head (2) can be moved quickly and accurately to a predetermined position. In addition, following the movement of the optical head (2), the moving body (37) that constitutes a part of the support member (3) will also move in the same direction, but in this case, the timing of these movements will be The movable body (37) may vibrate through the spring members (38) to (38) due to a slight deviation. However, since this movable body (37) is set to be lighter than the optical head (2), this vibration does not interfere with the moving operation of the optical head (2).

Furthermore, since the optical head (2) becomes lighter because the conventional driving coil for focus control is not required, the driving force is reduced accordingly, which has the advantage of improving movement accuracy.

[Effects of the Invention] As described above, the present invention allows the optical head itself to be directly moved in the track direction of the optical recording medium by the electromagnetic force accompanying the energization of the driving coil wound around the optical head. Since the head and the drive source are integrated, it is possible to prevent the generation of moment force during movement.

Therefore, the driving force applied to the optical head is stable, and the optical head can be moved quickly and accurately to a predetermined position.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the present invention, in which FIG. 1 is a partial perspective view of an optical recording and reproducing apparatus according to the embodiment, and FIG.
The figure is a sectional view from ■-■ of Figure 1, and Figure 3 is a cross-sectional view of ■-■ of Figure 1.
4 to 7 show a conventional example, FIG. 4 is a schematic diagram of the configuration of an optical recording/reproducing device, and FIG. 5 is an example of an optical head drive system. FIG. 6 is a sectional view taken along line Vl-V11, and FIG. 7 is a perspective view showing another example of the drive system. [Description of symbols] (1)...Optical recording medium (21>...Optical head...Supporting member...Driving coil...Prism...Objective lens (41)...Permanent magnet feature Applicant Fuji Xerox Co., Ltd. Representative Patent Attorney Tomohiro Nakamura (2 others) Figure

Claims (1)

[Scope of Claims] A reflecting member that is disposed near a rotating optical recording medium, floats due to the air flow accompanying the rotation of the optical recording medium, and reflects focused light from a light source toward the optical recording medium, and this reflecting member An optical head is equipped with an objective lens that converges the focused light reflected by the optical recording medium onto the converging surface of the optical recording medium, and a driving coil is wound around the optical head. A support member movably supports the optical recording medium, and a magnet that is provided along the track direction of the optical recording medium and forms lines of magnetic force toward the optical head. 1. An optical recording/reproducing device characterized in that the optical recording/reproducing device is operable to move along the track direction of an optical recording medium.