JPH01179122A - vibrating mirror device - Google Patents

Abstract

PURPOSE:To obtain a stable characteristic by eliminating the fluctuation of a spring constant in the twist direction caused by wiring by bringing a lead part of a coil to wiring equally to a turning axis of an elastic area of a plate spring, and also, fixing it at the outside of the elastic area. CONSTITUTION:Both ends of a plate spring 12 to which a reflecting means 13 and a coil 14 are stuck is fixed to a holder 11. A lead part 14a to the coil 14 is brought to wiring equally to a turning axis, and also, equally in two directions of the turning axis in an elasticity utilizing area of the plate spring 12, and fixed to the plate spring 12 at the outside of the elastic area. According to this constitution, a magnetic flux is formed by a permanent magnet 17 and a yoke 15, and by allowing a current to flow to the coil 14, a mirror is vibrated. In such a case, since the lead part 14a is brought to wiring as mentioned above, reaction force of the lead part 14a generated by turning of the plate spring 12 can be eliminated to the utmost, and by eliminating a fluctuation of a spring constant, a stable characteristic can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a vibrating mirror device that can be used as an optical deflector for an optical disk device that optically records information on a recording medium or optically reproduces information from the recording medium. It is.

BACKGROUND OF THE INVENTION In recent years, vibrating mirror devices have been widely used as actuators for controlling laser light focused by an objective lens in the tracking direction of a disk.

An example of a conventional vibrating mirror device will be described below with reference to the drawings. FIG. 4 is a schematic diagram of a conventional vibrating mirror device, FIG. 6 is a cross-sectional view taken along line DD in FIG. 4, and FIG. 6 is a cross-sectional view taken along line B-B in FIG. 4.

4, 6, and 6, reference numeral 1 denotes a holder made of a non-magnetic material, and both ends of a plate spring 2 are fixed by known means such as adhesive or screwing.

A coil 4 is fixed to the leaf spring 2 by means of adhesive or the like, and has a reflection step 3 on one side and a lead portion 4a for supplying current and which can be fixed with extra length on the other side. On the other hand, a yoke 6 is fixed to the holder 1, a spacer 6 made of a non-magnetic material is fixed to the yoke 6, and a permanent magnet 7 is fixed to the spacer 6 by adhesive or the like.

The operation of the vibrating mirror device configured as described above will be described below. In FIG. 4, magnetic flux is supplied to the coil 4 by the permanent magnet 7 and the yoke 6. Therefore, by passing current through the coil 4 from the lead portion 4a, the zero point of the leaf spring 2 (B-B in FIG. 4) twisting motion is possible around the axis). Note that the portions of the plate spring 2 that fix the holder 1, the reflecting means 3, and the coil 4 act as a rigid body, so that the actual spring portion is only the 8 portions shown in FIG. 4. Further, as shown in FIG. 6, the vibrating mirror device as an optical disk device emits an incident optical path from a laser, etc. (not shown) in the approximately 90' direction, and further detects the amount of deviation from an arbitrary track of the disk (not shown). A feedback circuit is constituted by an error detection means (not shown), a servo circuit (not shown) for passing a current corresponding to the error to the coil 4, etc.
This allows any track to be traced with high precision.

Problems to be Solved by the Invention However, in the above configuration, the lead part 4a itself has elasticity in the direction of torsional movement due to the wiring method of the lead part 4a, and the originally required spring constant of the leaf spring 2 cannot be obtained. do not have. Especially in a highly sensitive system, the spring constant is inevitably increased, which causes a decrease in the amount of rotation of the mirror per current flowing through the coil 4 and fluctuations in the resonance frequency, which only makes it difficult to adjust the servo circuit. Moreover, in some cases, when tracing an arbitrary track on a disk (not shown), there is a serious problem of increased tracing errors or the inability to trace. 'In view of the above problems, the present invention provides a stable vibrating mirror device that eliminates fluctuations in the torsional spring constant caused by the wiring of the lead portion 4a.

Means for Solving the Problems In order to solve the above problems, the vibrating mirror device of the present invention has the following features:
The lead portion is arranged so as to be substantially equal to the rotational axis in the elasticity utilization area of the leaf spring, and equally wired in two directions of the rotational axis, and fixed outside the elasticity utilization area.

Operation According to the above-described configuration, the present invention stabilizes the spring constant in the torsional direction mainly of the leaf spring by eliminating as much as possible the reaction force of the lead portion generated by the rotation of the leaf spring, the reflection means, and the coil.

EXAMPLE A vibrating mirror device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram of a vibrating mirror device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line CC in FIG. 1, and FIG. 3 is a cross-sectional view taken along line A-A in FIG. In FIGS. 1, 2, and 3, 11 is a holder made of non-magnetic material, and leaf spring 12 is
Both ends are fixed by known means such as gluing or screwing.

A reflecting means 13 is bonded to one side of the leaf spring 12, and a reflection means 13 is bonded to the other side for supplying current, and in the elastic utilization area of the leaf spring 12, wires are wired approximately equal to the rotation axis and equally in two opposite directions of the rotation axis. , the lead portion 14 fixed outside the elastic utilization area 14b
A coil 14 equipped with a is fixed by adhesive or other means. On the other hand, the holder 11 has a yoke 16, and this yoke 16
A spacer 16 made of a non-magnetic material is attached to the spacer 1.
A permanent magnet 17 is fixed to 6 by adhesive or the like. The operation of the vibrating mirror device configured as described above is the same as that of the conventional example, so a description thereof will be omitted. The difference between the conventional example and the embodiment of the present invention is that the lead portion 14a for current supply is replaced by the plate spring 1.
20. The wiring is approximately equal to the rotation axis in the elasticity utilization area and equally in two directions of the rotation axis, and is fixed outside the elasticity utilization area. This provides a vibrating mirror device that can suppress the influence of the lead portion 14a on the spring constant of the system and obtain stable characteristics.

Effects of the Invention As described above, the present invention includes a holder, a yoke member fixed to the holder, a magnet having a magnetic pole, a plate-shaped reflecting means having a flat reflecting surface, and a reflecting plane of the reflecting means. a plate spring having a rotating axis by twisting in a parallel direction, both ends of which are rotatably fixed to the holder or yoke member, and the reflecting means fixed to one side; and a direct or indirect member on the other side of the plate spring. One or more of the reflecting means and the plate spring are fixed to each other through a magnetic circuit constituted by the yoke member or the magnet having the magnetic poles, and the reflecting means and the leaf spring are rotated, and one or more of The direction from the beginning and end of winding of the coil to the end of the wire is at least in the elastic region of the leaf spring during rotational movement due to torsion of the leaf spring, and the rotation axis of the leaf spring and the reflecting means. The wires are wired approximately parallel and close to each other in two opposite directions of the rotation axis so that at least the wire diameter and the number of wires are symmetrical, and the wires are connected from the coil to the leaf spring in the direction in which the leaf spring and the holder or the yoke member are fixed. By fixing the wiring outside the elastic region, it is possible to suppress fluctuations in the spring constant of the system due to variations in wiring assembly, and to obtain stable characteristics.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a vibrating mirror device according to an embodiment of the present invention, FIG. 2 is a sectional view taken along the line C-C in FIG. 1, FIG. 3 is a sectional view taken along A-A in FIG. A schematic diagram of the vibrating mirror device, FIG. 6 is a sectional view taken along line D-D in FIG. 4, and FIG.
-B sectional view. 11... Holder, 12... Leaf spring,
13... Reflection means, 14... Coil,
16...Yoke, 17...Permanent magnet.

Claims (2)

[Claims] (1) A holder, a yoke member fixed to the holder, a magnet having magnetic poles, a reflecting means, and a rotatable rotating shaft having a rotating axis by twisting in a direction parallel to the reflecting plane of the reflecting means. Consisting of a plate spring having both ends fixed to a holder or a yoke member and the reflecting means fixed to one side, and a magnet having the yoke member or the magnetic pole fixed directly or indirectly to the other side of the plate spring. and a coil that causes the rotational motion of the leaf spring and a power generation effect due to the rotational motion, and the direction from the beginning and end of the coil to the end of the wire is at least Wired approximately parallel to the rotation axis of the leaf spring and the reflecting means in an elastic region of the leaf spring during rotational movement due to torsion of the leaf spring,
A vibrating mirror device characterized in that the wiring is fixed outside the elastic region of the plate spring in a direction from the coil to the plate spring and the holder or the yoke member. (2) The wiring is symmetrical in at least the wire diameter and the number of wires in two opposing directions in the direction of the rotation axis from the coil.
The vibrating mirror device described in section.