JP4137684B2 - Fine movement mechanism and optical switch - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to the field of a fine movement mechanism for driving an object in the field of fine technology.
[0002]
[Prior art]
In recent years, a small and low power consumption fine movement mechanism using a semiconductor process has been developed, and there is an optical switch as a functional element incorporating such a fine movement mechanism (for example, see Patent Document 1).
[0003]
5A is a top view of an optical switch incorporating a conventional fine movement mechanism, and FIG. 5B is a cross-sectional view of the broken line portion of FIG. 5A, which connects the movable electrode plate 41 and the outer frame 45 to each other. It is composed of four elastic bodies 43 and a fixed electrode plate 44. In order to operate as an optical switch, there are an input optical fiber 46, an output optical fiber 47 and an output optical fiber 48 installed in a T-shape, and a mirror 42 for switching the optical path. The mirror 42 is formed on the movable electrode plate 41. As shown by a solid line and a broken line in FIG. 5B, the mirror 42 is driven up and down to drive an optical signal 49 emitted from the input fiber 46. It is possible to switch the optical path. For example, when the mirror 42 is on the upper side, the optical signal 49 is reflected by the mirror 42 and coupled to the output optical fiber 47, and when it is on the lower side, the optical signal 49 is coupled to the output optical fiber 48 like the optical path 50. The In the present optical switch, the electrostatic attraction generated by applying a voltage to the movable electrode plate 41 and the fixed electrode plate 44 is extended for the downward movement of the movable electrode plate 41, and the upward movement is extended for the upward movement. The restoring force of the elastic body 43 is used.
[0004]
[Patent Document 1]
JP 2000-258702 A (5th page, FIG. 1)
[0005]
[Problems to be solved by the invention]
In the conventional example, since the movable electrode plate 41 is kept hollow only by the support from the elastic body 43 in the state shown by the solid line in FIG. 5B, the movable electrode plate is caused by external impact and vibration. 41 is easily oscillated, such as tilt and displacement. When the mirror 42 is formed on the movable electrode plate 41 as in the conventional example and used as an optical switch, if the mirror 42 is swung, the optical signal reflected by the mirror 42 is deviated from the intended optical path, and the output of the optical switch It causes malfunctions such as signal loss and loss. When the elastic body 43 is given high rigidity, the swinging of the movable electrode plate 41 can be reduced. However, since the restoring force by the elastic body 43 is increased, a large electrode area or a high voltage is required for driving the movable electrode plate 41. It becomes. Therefore, the advantages of small size and low power consumption are lost.
[0006]
The present invention provides a fine movement mechanism that reduces a swing and operates stably even in the presence of an impact and a vibration while maintaining the conventional advantages of small size and low power consumption.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, a fine movement mechanism according to the present invention includes a fixed substrate, an elastic body integrated with the fixed substrate, and a movable portion supported by the fixed substrate via the elastic body. The fine movement mechanism in which the parts are integrally formed using a fine processing technique is characterized by having a holding mechanism that applies a preload to the above-described movable part. Further, the above preload is applied to the movable part by displacing the movable part or applying pressure to the movable part. Further, the above holding mechanism is composed of a movable part holder, a movable part holder positioning structure, and a fixed structure, and the movable part holder that preloads the movable part is positioned on the movable part holder. It is characterized by maintaining the movable part by aligning the position with the structure and installing and fixing to the fixed structure. Furthermore, the movable part holder described above is a holding substrate having a rod-like elastic body such as an optical fiber or a sphere. Moreover, the above movable part holder positioning structure and fixing structure are either a concave structure or a through-hole. Furthermore, the cross section of the above-described concave structure is any one of a V shape, a U shape, and a rectangle, and the above concave structure or the opening of the through hole is a polygon or a circle.
[0008]
When the above holding mechanism applies a preload to the movable part, the movable part does not easily swing with respect to the driving direction even if it receives an impact or vibration from the outside. In addition, the positioning mechanism provided in the holding mechanism makes the structure not easily rocked except in the driving direction.
[0009]
In the present invention, a pair of optical fibers separated from each other has a mirror that changes a path of light passing through the optical fiber, and a support part that supports the mirror, and the mirror is sandwiched together with the support part. An optical switch having a pressurizing unit for applying pressure to the mirror was configured.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment 1)
A first embodiment of a fine movement mechanism using the present invention will be described below.
[0011]
FIG. 1 shows the structure of a 2 × 2 optical switch using the fine movement mechanism of the present invention. FIG. 1A is a perspective view thereof, and FIG. 1B is a cross-sectional view of a broken line portion of FIG. As shown in FIG. 1 (a), this optical switch is an optical waveguide for inputting / outputting optical signals, and is opposed to the V-groove 25 on the fixed substrate 3 two by two, so that an optical fiber 26, an optical fiber 27, The optical fiber 28 and the optical fiber 29 are fixed. As an optical element for switching the output direction of the optical signal, a mirror 20 is disposed between the facing optical fibers. As shown in FIG. 1B, the output direction of the optical signal is switched by driving the mirror 20 up and down using a fine movement mechanism. The optical path of the optical signal of this optical switch is shown in FIG. As shown in FIG. 2A, the optical path of the optical signal is emitted from the optical fiber 26 and the optical fiber 29, reflected by the mirror 20 on the optical path, and coupled to the optical fiber 27 and the optical fiber 28, respectively. As shown in FIG. 2B, the mirror 20 may move out of the optical path and go straight from the optical fiber 26 and the optical fiber 29 to the optical fiber 28 and the optical fiber 27. Although the configuration as the optical switch so far is different in the optical path to be switched, it can be said that the configuration of the movable part is almost the same as the conventional example.
[0012]
The fine movement mechanism of the present invention includes a movable portion 1 and a fixed substrate 3, an elastic body 2 that connects the fixed substrate 3 and the movable portion 1, and a holding mechanism. The holding mechanism includes a movable part holder 21, a V groove 22 formed in the movable part 1 as a holder positioning structure, and a V groove 23 and a pressing board 24 formed in the fixed substrate 3 as a fixed structure. As shown in FIG. 1A, the movable part holder 21 is disposed in the grooves of the V groove 22 and the V groove 23, and is fixed to the V groove 23 by a pressing substrate 24. As a driving means of the fine movement mechanism of the present invention, if an electrode is formed on the movable part 1 and a fixed electrode is provided on the opposing surface, it can be driven by electrostatic attraction, a magnetic material is formed on the movable part 1, and the opposing surface If an electromagnet or the like is installed in the, it can be driven by magnetic force.
[0013]
The effect of the movable part holder 21 will be described with reference to FIG. FIG. 3A is a view showing the fine movement mechanism in a state where the movable part holder 21 is not installed, and FIG. 3B is a view showing the fine movement mechanism in a state where the movable part holder 21 is installed. is there. As shown in FIG. 3A, the height of the movable portion 1 is formed to be higher by ΔZ than the upper surface of the fixed substrate 3. Therefore, as shown in FIG. 3B, when the movable part holder 21 is installed on the movable part 1 and the fixed substrate 3, the movable part 1 is displaced downward by ΔZ. As a result, a restoring force corresponding to ΔZ is generated upward from the elastic body 2. As described above, in a state where the movable part 1 is held by the movable part holder 21, a state where the restoring force by the elastic body 2 always acts on the movable part 1, that is, a state where preload acts can be obtained. In this state, even when a force is applied to the movable portion 1 due to external vibration or the like in the vertical direction, the state can be maintained if the force is weaker than the preload. Further, even if a force is applied in a direction other than the vertical direction in which the preload acts, the displacement can be reduced by the frictional force generated at the interface between the movable part holder 21 and the movable part 1.
[0014]
However, the frictional force alone cannot generate a force sufficient to maintain the state. Further, when the movable part 1 shifts from the broken line state in FIG. 1B to the solid line state, there is a possibility that the movable part 1 is held with a deviation in the XY direction in FIG. Therefore, in the holding mechanism of the present invention, the movable part holder positioning structure V-groove 22 is provided in the movable part 1. The V groove 22 reduces the displacement when the movable part 1 moves upward. Further, in the held state, when an external force is applied to the movable part 1, the movable part holder 21 is located in the V groove 22 and is in contact with the wall surface of the V groove 22. ), The movable portion 1 is held by the elastic force in the Y direction of the movable portion holder 21. This is the same even when the movable portion positioning structure is U-shaped or rectangular instead of V-shaped in cross section as in this embodiment. Or it is the same even if it is not a groove but a through-hole. Moreover, as the movable part holder 21, for example, a rod obtained by processing a metal material, a glass material, or a polymer material into a thin shape, an optical fiber, or the like can be used.
[0015]
Further, in the present embodiment, a step of ΔZ is formed on the upper surface of the movable part 1 and the fixed substrate 3 in order to apply preload from the movable part holder 21 to the movable part 1. However, even if the movable portion 1 and the fixed substrate 3 are not provided with a step, the movable portion holder 21 is processed so that the portion in contact with the movable portion 1 protrudes downward, or on the movable portion 1 and the fixed substrate 3. The same effect can be obtained even by a method of performing processing such that a step is provided only in a portion in contact with the movable part holder 21. In addition, as a method for applying a preload to the movable part 1, it is also possible to apply an electrostatic attractive force or a magnetic force to the movable part 1 and attract it in the driving direction.
[0016]
The fine movement mechanism of the present invention does not require reinforcement of the elastic body 2 unlike the conventional example in order to prevent the malfunction of the movable part 1, and does not increase the driving power associated therewith. This is a fine movement mechanism in which the swing of the movable part hardly occurs. Further, in the conventional fine movement mechanism, when the movable electrode plate 41 is moved from the broken line state to the solid line state in FIG. 5B, the movable electrode plate 41 does not stand still in the solid line state, and generates vibration according to the resonance frequency, so-called chattering. To do. Chattering is a damped vibration whose center is the state of the solid line, and it takes time until the vibration disappears. Therefore, the transition time from the broken line state to the solid line state includes not only the driving time but also the chattering decay time. However, in the fine movement mechanism of the present invention, since the movable part holder 21 reduces vibrations upward from the solid line state in FIG. 1B, the chattering decay time and consequently the transition time can be shortened.
[0017]
(Embodiment 2)
Next, a second embodiment of a fine movement mechanism using the present invention will be described below.
FIG. 4 is a diagram showing the structure of a second embodiment of a 2 × 2 optical switch using the fine movement mechanism of the present invention. 4A is a perspective view, FIG. 4B is a diagram showing the configuration of the holding substrate 33, and FIG. 4C is a diagram showing details of the holding mechanism. In the second embodiment, the structure is the same as that of the first embodiment except for the configuration related to the holding mechanism.
[0018]
The holding mechanism of the fine movement mechanism of the present invention is composed of a pressing substrate 33 serving as a movable part holder, and a concave structure 31 of a square pyramid serving as a holder positioning structure and a fixing structure. As shown in FIG. 4B, the holding substrate 33 has a concave structure 32 formed thereon. In the present embodiment, the shape of the concave structure 31 and the concave structure 32 is a quadrangular pyramid. However, for example, other polygonal pyramids, circular pyramids, polygonal columns, cylinders, and semicircles can also be used. Or a through-hole may be sufficient. A metal, glass, or polymer microsphere 30 is fixed to the concave structure 32.
[0019]
When the holding substrate 33 is placed on the movable portion 1 and the fixed substrate 3 by aligning the positions of the microsphere 30 and the concave structure 31 as shown in FIG. Thus, the preload can be applied to the movable part 1 as in the first embodiment. The effect of the preload is the same as that of the first embodiment, and it does not swing easily due to external impact and vibration.
[0020]
In the first embodiment, the movable part holder 21 and the V groove 22 which is a movable part holder positioning groove functioned in the Y direction. In the present embodiment, the microsphere 30 is an XY. Since it interferes with the four wall surfaces of the concave structure 31 corresponding to the direction, it becomes possible to hold the movable part 1 in each direction and to align with high accuracy.
[0021]
【The invention's effect】
According to the present invention, it is possible to provide a fine movement mechanism that is small in size, consumes low power, is strong against rocking such as tilt and displacement, and can be positioned with high accuracy.
[Brief description of the drawings]
FIG. 1 is a diagram showing an optical switch according to an embodiment of the present invention.
FIG. 2 is a diagram showing an optical path of an optical switch according to one embodiment of the present invention.
FIG. 3 is a view showing an optical switch holding mechanism according to an embodiment of the present invention.
FIG. 4 is a diagram illustrating an optical switch according to a second embodiment of the present invention.
FIG. 5 is a diagram showing a conventional optical switch.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Movable part 2 Elastic body 3 Fixed board | substrate 20 Mirror 21 Rod-type movable part holder 22 V groove | channel 23 for fixed board | substrate side movable part holders V groove | channel 24 for movable part side movable part holders Pressing substrates 25 Light for optical signal input / output Fiber V-groove 26 Optical signal input / output optical fiber 27 Optical signal input / output optical fiber 28 Optical signal input / output optical fiber 29 Optical signal input / output optical fiber 30 Microsphere type movable part holder 31 Movable part / fixed substrate Side square pyramidal concave structure 32 Holding substrate side pyramidal concave structure 33 Holding substrate 41 Movable electrode plate 42 Mirror 43 Elastic body 44 Fixed electrode plate 45 Outer frame 46 Input optical fiber 47 Output optical fiber 48 Output optical fiber 49 Optical signal 50 Optical path

Claims (15)

A fixed substrate comprising a plurality of optical fibers;
A movable part holder;
A movable part supported by an elastic body connected to the fixed substrate and pressed against the movable part holder by the elastic body;
A drive unit that drives the movable unit from a pressed state in which the movable unit is pressed against the movable unit holder to a separated state in which the movable unit is separated from the movable unit holding unit;
The movable portion includes a mirror that reflects light from the optical fiber when the movable portion is in the pressed state and passes light from the optical fiber when the movable portion is in the separated state. ,
A fine movement mechanism provided in the movable part, comprising a holder positioning structure for positioning the movable part holder with respect to the movable part. A fixed substrate comprising a plurality of optical fibers;
A movable part holder;
A movable part supported by an elastic body connected to the fixed substrate and pressed against the movable part holder by the elastic body;
A drive unit that drives the movable unit from a pressed state in which the movable unit is pressed against the movable unit holder to a separated state in which the movable unit is separated from the movable unit holding unit;
The movable portion includes a mirror that reflects light from the optical fiber when the movable portion is in the pressed state and passes light from the optical fiber when the movable portion is in the separated state. ,
One of the movable part and the movable part holder is
A fine movement mechanism comprising a step portion that has a thickness in a thickness direction of the movable portion and increases an urging force of the elastic body. The holder positioning structure is
The fine movement mechanism according to claim 1, further comprising a fixing structure that fixes the positioned movable part holder.   The fine movement mechanism according to claim 1, wherein the movable part holder has elasticity.   The fine movement mechanism according to claim 1, wherein the movable part holder is a rod.   3. The fine movement mechanism according to claim 1, wherein the movable part holder is a holding substrate that holds the movable part via a sphere.   The fine movement mechanism according to claim 5, wherein the movable part holder of the rod is an optical fiber.   The fine movement mechanism according to claim 3, wherein the holder positioning structure and the fixing structure are concave structures.   The fine movement mechanism according to claim 3, wherein the holder positioning structure or the fixing structure is a through hole.   The fine movement mechanism according to claim 8, wherein the concave structure is a groove structure.   The fine movement mechanism according to claim 8, wherein a cross section of the concave structure is V-shaped.   The fine movement mechanism according to claim 8, wherein a cross section of the concave structure is U-shaped.   The fine movement mechanism according to claim 8, wherein a cross section of the concave structure is rectangular.   10. The fine movement mechanism according to claim 8, wherein an end surface shape of the concave structure or the through hole is a polygon.   10. The fine movement mechanism according to claim 8, wherein an end surface shape of the concave structure or the through hole is circular.

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