JP2006018176A - Electrostatic type variable shape mirror - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrostatic type variable shape mirror capable of largely deforming a reflection film by low-voltage driving. <P>SOLUTION: The electrostatic type variable shape mirror 10 for deforming the flexible reflecting film 20 by electrostatic force and changing the degree of convergence or divergence or deflection of light made incident on the reflecting film 20 is equipped with a substrate electrode 40 fixed and arranged on a substrate 50, and a conductive thin plate member 30 arranged facing the substrate electrode 40. The thin plate member 30 has a substrate connection part fixed on the substrate 50, and a reflecting film connecting part jointed to the reflection film 20; and by applying voltage between the substrate electrode 40 and the thin plate member 30 and deforming the shape of the thin plate member 30, the reflecting film connecting part is displaced toward the substrate and the curvature of the reflection film 20 is changed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electrostatic deformable mirror that deforms a flexible reflective film by an electrostatic force and changes a degree of convergence, divergence, or deflection of light incident on the reflective film.

  Ultra-compact that can change the curvature of the reflective film for the purpose of simplifying the mechanism related to focusing, etc. that used an electromagnetic actuator in a micro optical system that has been applied to micro-optics such as optical pickups. There have been proposals for deformable mirrors. Even in a small imaging optical system, the application of the deformable mirror can greatly contribute to miniaturization. Such a deformable mirror can be expected to be manufactured at low cost and high accuracy by applying a so-called MEMS (Micro Electro-Mechanical System) technology to which semiconductor manufacturing technology is applied.

As an example of such a deformable mirror, for example, in Patent Document 1, an upper electrode having a reflective film and a substrate electrode are arranged to face each other, and an electrostatic attraction generated by applying a voltage between both electrodes is applied. An electrostatic deformable mirror that is used to change the curvature of a reflective film is disclosed. Such electrostatic variable shape mirrors are electromagnetic variable shape mirrors that change the curvature of the reflection film by magnetic force using a permanent magnet or electromagnet, and the curvature of the reflection film by a pressure change in the sealed space using a pump. Compared to a pressure-type deformable mirror that changes pressure, it can be driven with low power consumption, and has a great merit in that it can be made thin and small.
Japanese Patent Laid-Open No. 2-101402

  Generally, the electrostatic attractive force acting between parallel flat plates is inversely proportional to the square of the distance between both electrodes. Further, in such a parallel plate type electrostatic actuator, when the upper electrode is deformed by about 1/3 or more of the initial electrode interval, a stacking phenomenon that abruptly sticks to the substrate electrode occurs.

  Therefore, in the conventional electrostatic deformable mirror, when the reflective film is largely deformed, it is necessary to set a longer interval between the upper electrode and the substrate electrode, and the applied voltage is inevitably high. Inconvenience occurred.

  The present invention has been made in view of the above points, and an object of the present invention is to provide an electrostatic deformable mirror that can largely deform a reflective film by driving at a low voltage.

One aspect of the electrostatic deformable mirror of the present invention is:
In the electrostatic deformable mirror that changes the degree of convergence or divergence or deflection of the light incident on the reflective film by deforming the reflective film with flexibility by electrostatic force,
A substrate electrode disposed fixed to the substrate;
A thin plate-like member having conductivity disposed to face the substrate electrode;
Comprising
The thin plate member has a substrate connection portion fixed to the substrate and a reflection film connection portion bonded to the reflection film,
A voltage is applied between the substrate electrode and the thin plate member to change the shape of the thin plate member, thereby displacing the reflective film connecting portion in the direction of the substrate and changing the curvature of the reflective film. It is characterized by that.

  According to the present invention, it is possible to provide an electrostatic deformable mirror that can largely deform a reflective film by driving at a low voltage.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

[First Embodiment]
An electrostatic deformable mirror according to a first embodiment of the present invention will be described with reference to FIGS.

  First, the configuration of the electrostatic deformable mirror according to the first embodiment will be described.

  1A and 1B are perspective views of an electrostatic deformable mirror 10 according to the present embodiment. Note that the electrostatic deformable mirror 10 illustrated in FIG. 1B is a diagram in which the flexible reflective film 20 is removed from the electrostatic deformable mirror 10 illustrated in FIG.

  As shown in FIGS. 1A and 1B, an electrostatic deformable mirror 10 according to this embodiment includes a substrate 50, a plurality of substrate electrodes 40 fixed to the substrate 50, and external lead electrodes. 60, an insulating film 70 formed on the surface layer of the substrate 50 so as to cover the substrate electrode 40, and at least one end (substrate connecting portion) is fixed to the substrate 50, and is disposed to face the substrate electrode 40. The thin plate-like member 30 having a plurality of conductivity and the one end (reflection film connecting portion) not fixed to the substrate 50 of the thin plate-like member 30 are supported by the thin plate-like member 30. It is comprised from the reflecting film 20 which has flexibility.

  Here, details of the substrate electrode 40 and the thin plate member 30 will be described with reference to FIG. 2 which is an enlarged perspective view showing the substrate electrode 40 and the thin plate member 30. That is, as shown in the figure, the substrate electrode 40 is formed in a circular shape on the substrate 50 and is connected to the substrate electrode lead-out wiring 41. The insulating film 70 is formed on the surface layer of the substrate 50 so as to cover the substrate electrode 40. On the other hand, the thin plate-like member 30 is formed in a state in which one end serving as a substrate connecting portion is fixed to the substrate 50, faces the substrate electrode 40, and protrudes in a spiral shape. A portion of the thin plate member 30 fixed to the substrate 50 is connected to the movable electrode lead-out wiring 31 through a contact hole 80 formed in the insulating film 70.

  FIG. 3 shows another embodiment of the substrate electrode 40 and the thin plate member 30. That is, as shown in the figure, the substrate electrode 40 is formed in a square shape on the substrate 50 and connected to the substrate electrode lead-out wiring 41. An insulating film 70 is formed on the surface layer of the substrate 50 so as to cover the substrate electrode 40. On the other hand, the thin plate-like member 30 is formed in a state where one end serving as a substrate connecting portion is fixed to the substrate 50, faces the substrate electrode 40, and protrudes in a pantograph shape. A portion of the thin plate member 30 fixed to the substrate 50 is connected to the movable electrode lead-out wiring 31 through a contact hole 80 formed in the insulating film 70.

  Of course, various forms other than the substrate electrode 40 and the thin plate member 30 shown in FIGS. 2 and 3 are conceivable.

  Each of the thin plate-like members 30 shown in FIGS. 1A and 1B is connected to the external lead electrode 60 via the movable electrode lead-out wiring 31 shown in FIG. All the substrate electrodes 40 shown in 1 (A) and 1 (B) are connected to a single external lead electrode 60 through the substrate electrode lead-out wiring 41 shown in FIG.

  Next, the operation of the electrostatic deformable mirror 10 according to the first embodiment will be described.

  When a voltage is applied from the external lead electrode 60 between the substrate electrode 40 and the thin plate member 30 shown in FIG. 2, an electrostatic attractive force acts between the two, and the thin plate member 30 is attracted to the substrate electrode 40 side. It deforms as follows. Further, the portion (reflective film connecting portion) of the reflective film 20 that is coupled to the thin plate member 30 is also displaced toward the substrate 50 as the thin plate member 30 is deformed. Such displacement of the thin plate member 30 and the reflective film 20 can be controlled by a voltage value applied between the substrate electrode 40 and the thin plate member 30.

  Accordingly, as shown in FIGS. 1A and 1B, a plurality of substrate electrodes 40 and thin plate members 30 are arranged, and the displacement amount of each thin plate member 30 is controlled independently, or the thin plate members 30 are arranged. Is divided into a plurality of groups and controlled for each group, the reflection film 20 can be changed to a desired curvature, and the degree of convergence, divergence, or deflection of the light incident on the reflection film 20 can be changed. Details regarding the control method will be described later.

  The electrostatic attractive force acting between the substrate electrode 40 and the thin plate member 30 depends on the potential difference between the two, and therefore does not depend on the grounding state or the like. For example, the substrate electrode 40 may be grounded and a voltage may be applied to the thin plate member 30, or the reverse relationship may be applied. Also, different voltages may be applied to both without grounding one of them. Therefore, in this specification, the expression “applying a voltage between the substrate electrode and the thin plate member” is used to apply a potential difference to the substrate electrode and the thin plate member regardless of the method. It shall represent.

  Hereinafter, a specific example in which the curvature of the reflective film 20 is changed will be described with reference to FIGS. 4A to 4D are cross-sectional views of the electrostatic deformable mirror 10 in FIGS. 1A and 1B taken along line AA.

  That is, FIG. 4A is a diagram showing an initial state in which no voltage is applied to all the substrate electrodes 40 and the thin plate-like member 30. In this case, the reflective film 20 is flat.

  FIG. 4B is a diagram showing a case where the voltage value to be gradually applied between the substrate electrode 40 and the thin plate member 30 disposed from the outer peripheral portion to the central portion is increased. In such an applied state, the amount of displacement of the thin plate-like member 30 disposed in the central portion is larger than that in the outer peripheral portion. Therefore, the reflective film 20 is concave. In this case, by controlling the voltage value to be applied, it is possible to control the curvature of the reflective film 20 having the concave surface.

  FIG. 4C shows a case where the voltage value to be gradually applied between the substrate electrode 40 and the thin plate member 30 disposed from the central portion to the outer peripheral portion is increased. In such an applied state, the amount of displacement of the thin plate-like member 30 disposed in the outer peripheral portion is larger than that in the central portion, so that the reflective film 20 becomes a convex surface. In this case, the curvature of the reflective film 20 having the convex surface can be controlled by controlling the voltage value to be applied.

  FIG. 4D shows a state in which a voltage is applied between an arbitrary substrate electrode 40 and the thin plate member 30. In such an applied state, the reflective film 20 has a free wavefront. In this case, by controlling the voltage value to be applied, it is possible to control the curvature of the reflective film 20 that has become the free wavefront.

  In this way, by controlling the distribution of the voltage applied between the substrate electrode 40 and the thin plate-like member 30, the reflective film 20 is changed to various curvatures such as a concave surface, a convex surface, and a free wavefront, and the reflective film The light incident on 20 can be converged, diverged or deflected, and the degree of convergence, divergence or deflection can be controlled by controlling the applied voltage value.

  As described above, the “curvature” of the reflecting film in the present specification is not limited to the curvature captured as a part of a spherical surface as shown in FIGS. It is assumed that “curvature” includes a partial bend as shown in (D).

  Next, the rigidity of the thin plate member 30 and the reflective film 20 in the electrostatic deformable mirror 10 according to the first embodiment is an enlarged view of the joint between the thin plate member 30 and the reflective film 20. This will be described with reference to FIGS.

  That is, FIG. 5A shows a state in which the rigidity of the thin plate member 30 and the rigidity of the reflective film 20 are appropriately balanced. In this case, the reflective film 20 is a curved surface.

  On the other hand, FIG. 5B shows a state where the rigidity of the reflective film 20 is extremely lower than the rigidity of the thin plate member 30. In such a situation, the reflective film 20 is suddenly bent at the joint portion of the thin plate member 30, and the reflective film 20 becomes a flat aggregate instead of a curved surface. The general usage of the electrostatic deformable mirror 10 according to the present embodiment uses the reflective film 20 as a curved surface, and thus inconvenience occurs in the state shown in FIG. 5B.

  On the other hand, although not shown, when the rigidity of the reflecting film 20 is extremely higher than the rigidity of the thin plate member 30, the reflecting film 20 is not easily deformed, and the reflecting film 20 remains in a flat state and is translated or tilted. Behaves like this. In such a state, it is not possible to converge or diverge light incident on the reflective film 20 which is the original purpose of the electrostatic deformable mirror 10 according to the present embodiment.

  In order to deform the reflective film 20 into a curved surface as described above, the rigidity of the reflective film 20 is preferably in the range of 0.5 to 1.5 times the rigidity of the thin plate member 30. Desirably, the rigidity of the reflective film 20 and the rigidity of the thin plate member 30 are substantially equal.

  Next, regarding the arrangement of the substrate electrode 40 and the thin plate member 30 in the electrostatic deformable mirror 10 according to the first embodiment, the reflective film 20 of the electrostatic deformable mirror 10 is changed to a desired curvature. A description will be given with reference to FIGS. 6A and 6B which are diagrams showing examples of arrangement of the substrate electrode 40 and the thin plate member 30 in FIG. FIG. 6B shows a cross-sectional view of the electrostatic deformable mirror 10 of FIG. 6A taken along line BB.

  Here, in FIG. 6A, a broken line is an equidisplacement line 100 connecting points where the displacement amounts of the respective points in the surface of the reflection film 20 are equal in a state where the reflection film 20 is changed to a desired curvature. is there. 6B is a level 101 indicating the displacement of the thin plate member 30.

  Since the equal displacement line 100 is a point where the amount of displacement of the reflection film 20 is equal, as shown in FIG. 6B, the thin plate-like member 30 disposed along the equal displacement line 100 is deformed equally to obtain a desired value. The curvature can be easily obtained. Therefore, by arranging the substrate electrode 40 and the thin plate member 30 along the equal displacement line 100, a desired curvature can be obtained relatively easily.

  6A and 6B, the interval between the right equal displacement lines 100 is wider than the interval between the left equal displacement lines 100. The interval between the equal displacement lines 100 represents the curvature of the reflection film 20, and the curvature of the reflection film 20 increases as the interval between the equal displacement lines 100 decreases. When the film curvature is increased, the distortion increases and the force required for deformation also increases. Therefore, it is desirable that the substrate electrode 40 and the thin plate-like member 30 are densely arranged in a portion having a large curvature, that is, a portion where the interval between the equal displacement lines 100 is narrow.

  In addition, when changing the curvature of the reflective film 20, the amount of deformation of the reflective film 20 can be substantially controlled by the portion joined to the thin plate-like member 30. The curvature is determined by the rigidity of the reflective film 20. Therefore, in a state where the reflection film 20 is changed to a desired curvature, when there are a portion where the curvature needs to be strictly controlled and a portion where the curvature is not necessary, the portion where the curvature needs to be strictly controlled, It is desirable to arrange the substrate electrode 40 and the thin plate member 30 more closely.

  FIGS. 7A and 7B and FIGS. 8A and 8B are diagrams for explaining another arrangement example of the substrate electrode 40 and the thin plate member 30, respectively.

  FIGS. 7A and 7B show an arrangement example of the substrate electrode 40 and the thin plate member 30 in the case of the electrostatic deformable mirror 10 having a circularly symmetrical curvature with respect to the reflection film 20 of a perfect circle. FIG. FIG. 7B shows a cross-sectional view of the electrostatic deformable mirror 10 of FIG. 7A taken along line CC. In the electrostatic deformable mirror 10 as described above, the equal displacement lines 100 of the reflective film 20 are concentric as described above. Therefore, it is desirable that the substrate electrode 40 and the thin plate member 30 be arranged concentrically.

  8A and 8B show an arrangement example of the substrate electrode 40 and the thin plate member 30 in the case of the electrostatic deformable mirror 10 in which the rectangular reflecting film 20 has a wavefront curvature. It is a figure. FIG. 8B shows a cross-sectional view of the electrostatic deformable mirror 10 of FIG. 8A taken along the line DD. In the electrostatic deformable mirror 10 as described above, the equal displacement line 100 of the reflective film 20 becomes a parallel line as described above. Therefore, it is desirable that the substrate electrode 40 and the thin plate member 30 be arranged on the parallel line.

  Next, a method for controlling the thin plate member 30 in the electrostatic deformable mirror 10 according to the first embodiment will be described.

  As a method for controlling the electrostatic deformable mirror 10 shown in FIGS. 1A and 1B, for example, all substrate electrodes 40 are connected to a common external lead electrode 60 and grounded, and each thin plate is connected. The individual members 30 may be connected to the external lead electrodes 60 and voltage may be applied independently. Of course, the connection state of the substrate electrode 40 and the thin plate member 30 may be reversed. Also, different voltages may be applied to both without grounding one of them.

  Since this method can control the displacement amount of each thin plate member 30 independently, it can be used when the curvature of the reflective film 20 is set freely or when a plurality of patterns are set.

  As another method, a method of dividing the thin plate member 30 or the substrate electrode 40 into a plurality of groups is also conceivable. FIG. 9 is a view showing the reflective film 20 and the thin plate member 30 extracted from the electrostatic deformable mirror 10 shown in FIGS. 6 (A) and 6 (B).

  As described above with respect to the arrangement of the substrate electrode 40 and the thin plate member 30, when changing the reflection film 20 to a desired curvature, the thin plate member 30 arranged along the same equal displacement line 100 is equally deformed. Thus, a desired curvature can be obtained. Therefore, as shown in FIG. 9, the thin plate-like members 30-1 to 30-4 arranged along the equal displacement lines 100-1 to 100-4 are divided into groups, respectively. Then, all the substrate electrodes 40 are connected to the common external lead electrode 60 and grounded, and the thin plate-like members 30-1 to 30-4 divided into groups are connected to the external lead electrode 60, respectively. Apply voltage. By doing in this way, since the thin plate member 30 which belongs to each group can be deformed equally, the thin plate member 30 arrange | positioned along the same equal displacement line 100 can be changed equally easily. Of course, the connection state of the substrate electrode 40 and the thin plate member 30 may be reversed. Also, different voltages may be applied to both without grounding one of them.

  Next, operations and effects of the electrostatic deformable mirror 10 according to the first embodiment will be described.

  Generally, the electrostatic attractive force acting between parallel flat plates is inversely proportional to the square of the distance between both electrodes. Further, in such a parallel plate type electrostatic actuator, when the upper electrode is deformed by more than 1/3 of the initial electrode interval, a stacking phenomenon that abruptly sticks to the substrate electrode occurs.

  In the configuration of the conventional electrostatic deformable mirror, the upper electrode is formed integrally with the reflecting film. Therefore, when the reflecting film is largely deformed, the distance between the upper electrode and the substrate electrode needs to be set longer accordingly. Inevitably, there was a disadvantage that the applied voltage was high.

  On the other hand, the electrostatic deformable mirror 10 according to the first embodiment applies a voltage between the substrate electrode 40 and the reflective film 20 as shown in FIGS. 1 (A) and 1 (B). Instead, the curvature of the reflective film 20 is indirectly changed by applying a voltage between the substrate electrode 40 and the thin plate member 30 to deform the thin plate member 30. Further, since the base portion of the thin plate member 30 is close to the substrate electrode 40, a large electrostatic attraction is generated at the base portion of the thin plate member 30, and the thin plate member 30 starts to deform at a relatively low voltage. . According to such a configuration, the deformation of the thin plate member 30 is not related to the distance between the substrate electrode 40 and the reflective film 20, so that the substrate film 40 and the reflective film 20 are deformed in order to greatly deform the reflective film 20. Even if the interval is set long, it is possible to drive at a low voltage.

  Further, the electrostatic attractive force acting between the electrodes is only an attractive force, and no repulsive force is generated. Therefore, in the configuration of the conventional electrostatic deformable mirror, the reflective film can only be deformed into a concave surface. In addition, as a method of deforming the reflective film into a convex surface using a conventional configuration, a voltage is applied between the transparent electrode and the reflective film using a transparent substrate or the like in which a transparent electrode is formed on the entire surface of the reflective film. It is necessary to deform the reflective film into a convex surface by the electrostatic attractive force generated in step 1, and there is a risk that the configuration is complicated and the size is increased.

  On the other hand, as described above, the electrostatic deformable mirror 10 according to the first embodiment can deform the reflective film 20 into various shapes such as an uneven surface and a free wave surface. .

[Second Embodiment]
Next, an electrostatic deformable mirror according to a second embodiment of the present invention will be described with reference to FIGS. Here, FIG. 10A shows a top view of the electrostatic deformable mirror 10 according to the second embodiment, and FIGS. 10B and 10C are both shown in FIG. It is sectional drawing which cut | disconnected the electrostatic-type deformable mirror 10 in EE line | wire.

  The electrostatic deformable mirror 10 according to the second embodiment is different from the first embodiment in that the reflective film 20 is supported by the frame member 90.

  When the reflective film 20 is supported only by the thin plate member 30 as in the first embodiment, at least two thin plate members 30 are required, and more thin plate members 30 are required when actually used. Necessary.

  On the other hand, according to the configuration of the second embodiment, the curvature of the reflective film 20 can be changed with only one thin plate member 30.

  In addition, since the reflective film 20 is supported not only by the thin plate member 30 but also by the frame member 90, high initial flatness can be obtained even if a thin film having relatively low rigidity is used for the reflective film 20. For example, when a thin film having a relatively thin film thickness is used as the reflection film 20, it is difficult to obtain a high initial flatness if it is supported only by the thin plate member 30. However, high initial flatness can be obtained by supporting the reflective film 20 with the frame member 90 in a state where a certain amount of tension is applied.

  In the electrostatic deformable mirror 10 having the configuration of the second embodiment, the curvature of the reflective film 20 is applied by applying a voltage between the substrate electrode 40 and the thin plate member 30 as in the first embodiment. Can be changed from a flat surface to a concave surface.

  In addition, as shown in FIG. 10C, in the initial state, the reflective film 20 is made convex so that the convex surface can be changed to a flat surface and a concave surface.

[Third Embodiment]
Next, an electrostatic deformable mirror according to a third embodiment of the present invention will be described with reference to FIGS. 11 (A) and 11 (B). 11A shows a top view of the electrostatic deformable mirror 10 according to the third embodiment, and FIG. 11B shows the electrostatic deformable mirror in FIG. 11A. It is sectional drawing which cut | disconnected 10 by the FF line.

  The electrostatic deformable mirror 10 according to the third embodiment differs from the first embodiment described above in that the reflective film 20 is supported by the frame member 90, and the substrate electrode 40 and the thin plate member 30. Is different from the second embodiment in that a plurality of are formed.

  That is, in the electrostatic deformable mirror 10 according to the third embodiment, the reflective film 20 is supported by the frame member 90 as shown in FIGS. High initial flatness can be obtained even with a film having low mechanical rigidity. In addition, since a plurality of thin plate-like members 30 are formed, the reflective film 20 can be deformed not only to a simple uneven surface, but also to an uneven surface having a different curvature or a complex wave surface.

  Although the present invention has been described above based on the embodiments, the present invention is not limited to the above-described embodiments, and various modifications and applications are naturally possible within the scope of the gist of the present invention.

(Appendix)
The invention having the following configuration can be extracted from the specific embodiment.

(1) In an electrostatic deformable mirror that deforms a flexible reflective film by electrostatic force and changes the degree of convergence, divergence, or deflection of light incident on the reflective film,
A substrate electrode disposed fixed to the substrate;
A thin plate-like member having conductivity disposed to face the substrate electrode;
Comprising
The thin plate member has a substrate connection portion fixed to the substrate and a reflection film connection portion bonded to the reflection film,
A voltage is applied between the substrate electrode and the thin plate member to change the shape of the thin plate member, thereby displacing the reflective film connecting portion in the direction of the substrate and changing the curvature of the reflective film. An electrostatic deformable mirror characterized by that.

(Corresponding embodiment)
The first to third embodiments correspond to the embodiment of the electrostatic deformable mirror described in (1).

(Function and effect)
The electrostatic deformable mirror described in (1) includes a substrate electrode 40 and a conductive thin plate having at least one end fixed to the substrate 50 and disposed opposite to the substrate electrode 40 on the substrate 50. The thin member 30 and the reflective film 20 that is coupled to one end of the thin plate member 30 that is not fixed to the substrate 50 and supported by the thin plate member 30 are formed. Alternatively, on the substrate 50, the substrate electrode 40, at least one end of which is fixed to the substrate 50, the conductive thin plate member 30 disposed to face the substrate electrode 40, and the substrate 50 of the thin plate member 30. A reflective film 20 is formed which is coupled to one end not fixed to the frame and supported by the frame member 90.

  Therefore, according to the electrostatic deformable mirror described in (1), a voltage is applied between the substrate electrode 40 and the thin plate-like member 30 to deform the thin plate-like member 30 to indirectly reflect the reflective film 20. Therefore, even if the initial interval between the substrate electrode 40 and the reflective film 20 is set long in order to largely deform the reflective film 20, it is possible to drive with a low voltage.

  (2) The electrostatic deformable mirror according to (1), wherein the flexible reflective film is supported by a frame material.

(Corresponding embodiment)
The second and third embodiments correspond to the embodiment of the electrostatic deformable mirror described in (2).

(Function and effect)
In the electrostatic deformable mirror described in (2), the reflective film 20 is supported by a frame member 90.

  Therefore, according to the electrostatic deformable mirror described in (2), it is possible to obtain high initial flatness by supporting the reflective film 20 with the frame material 90 in a state where a certain amount of tension is applied. Become.

  (3) The electrostatic deformable mirror according to (1) or (2), wherein the rigidity of the flexible reflective film is substantially equal to the rigidity of the thin plate member.

(Corresponding embodiment)
The embodiment relating to the electrostatic deformable mirror described in (3) corresponds to the first embodiment.

(Function and effect)
In a state where the rigidity of the reflective film 20 is extremely lower than the rigidity of the thin plate member 30, the reflective film 20 is abruptly bent at the joint portion of the thin plate member 30, so that the reflective film 20 is not a curved surface but a flat aggregate. Become. Further, in a state where the rigidity of the reflection film 20 is extremely higher than the rigidity of the thin plate member 30, the reflection film 20 is not easily deformed, and the reflection film 20 exhibits a behavior such as translation or tilt while being in a planar state. End up.

  Therefore, in the electrostatic deformable mirror described in (3), the rigidity of the reflective film 20 and the thin plate member 30 is made substantially equal.

  Therefore, according to the electrostatic deformable mirror described in (3), the reflective film 20 can be deformed into a curved surface.

  (4) The static reflection film according to (1) or (2), wherein the rigidity of the flexible reflective film is in the range of 0.5 to 1.5 times the rigidity of the thin plate member. Electric deformable mirror.

(Corresponding embodiment)
The embodiment relating to the electrostatic deformable mirror described in (4) corresponds to the first embodiment.

(Function and effect)
In a state where the rigidity of the reflective film 20 is extremely lower than the rigidity of the thin plate member 30, the reflective film 20 is abruptly bent at the joint portion of the thin plate member 30, so that the reflective film 20 is not a curved surface but a flat aggregate. Become. Further, in a state where the rigidity of the reflection film 20 is extremely higher than the rigidity of the thin plate member 30, the reflection film 20 is not easily deformed, and the reflection film 20 exhibits a behavior such as translation or tilt while being in a planar state. End up.

  Therefore, in the electrostatic deformable mirror described in (4), the rigidity of the reflective film 20 is in the range of 0.5 to 1.5 times the rigidity of the thin plate member 30.

  Therefore, according to the electrostatic deformable mirror described in (4), the reflective film 20 can be deformed into a curved surface.

  (5) The electrostatic deformable mirror according to (1), wherein a plurality of the substrate electrodes and the thin plate-like members are arranged.

(Corresponding embodiment)
The embodiment relating to the electrostatic deformable mirror described in (5) corresponds to the first and third embodiments.

(Function and effect)
In the electrostatic deformable mirror described in (5), a plurality of substrate electrodes 40 and a plurality of thin plate members 30 are formed.

  Therefore, according to the electrostatic deformable mirror described in (5), the curvature of the reflective film 20 can be changed not only to a single uneven surface but also to a complex uneven surface and free wavefront.

  (6) The electrostatic deformable mirror according to (5), wherein the flexible reflective film is supported by the thin plate member.

(Corresponding embodiment)
The embodiment relating to the electrostatic deformable mirror described in (6) corresponds to the first embodiment.

(Function and effect)
In the electrostatic deformable mirror described in (6), the reflective film 20 is supported by the thin plate member 30.

  Therefore, according to the electrostatic deformable mirror described in (6), since the reflective film 20 is not tensioned, the influence of elongation is reduced when the curvature of the reflective film 20 is changed. The curvature of the reflective film 20 can be changed by electrostatic attraction.

  (7) The electrostatic deformable mirror according to (5), wherein the flexible reflective film is supported by a frame material.

(Corresponding embodiment)
The second and third embodiments correspond to the embodiment of the electrostatic deformable mirror described in (7).

(Function and effect)
In the electrostatic deformable mirror described in (7), the reflective film 20 is supported by the frame member 90.

  Therefore, according to the electrostatic deformable mirror described in (7), it is possible to obtain a high initial flatness by supporting the reflective film 20 with a certain amount of tension by the frame member 90. Become.

  (8) The electrostatic variable shape mirror according to any one of (5) to (7), wherein the flexible reflective film has rigidity substantially equal to that of the thin plate member.

(Corresponding embodiment)
The embodiment relating to the electrostatic deformable mirror described in (8) corresponds to the first embodiment.

(Function and effect)
In a state where the rigidity of the reflective film 20 is extremely lower than the rigidity of the thin plate member 30, the reflective film 20 is abruptly bent at the joint portion of the thin plate member 30, so that the reflective film 20 is not a curved surface but a flat aggregate. Become. Further, in a state where the rigidity of the reflection film 20 is extremely higher than the rigidity of the thin plate member 30, the reflection film 20 is not easily deformed, and the reflection film 20 exhibits a behavior such as translation or tilt while being in a planar state. End up.

  Therefore, in the electrostatic deformable mirror described in (8), the rigidity of the reflective film 20 and the thin plate member 30 is substantially equal.

  Therefore, according to the electrostatic deformable mirror described in (8), the reflective film 20 can be deformed into a curved surface.

  (9) The rigidity of the flexible reflective film is in the range of 0.5 to 1.5 times the rigidity of the thin plate member, (5) to (7), The electrostatic deformable mirror described.

(Corresponding embodiment)
The embodiment relating to the electrostatic deformable mirror described in (9) corresponds to the first embodiment.

(Function and effect)
In a state where the rigidity of the reflective film 20 is extremely lower than the rigidity of the thin plate member 30, the reflective film 20 is abruptly bent at the joint portion of the thin plate member 30, so that the reflective film 20 is not a curved surface but a flat aggregate. Become. Further, in a state where the rigidity of the reflection film 20 is extremely higher than the rigidity of the thin plate member 30, the reflection film 20 is not easily deformed, and the reflection film 20 exhibits a behavior such as translation or tilt while being in a planar state. End up.

  Therefore, in the electrostatic deformable mirror described in (9), the rigidity of the reflective film 20 is in the range of 0.5 to 1.5 times the rigidity of the thin plate member 30.

  Therefore, according to the electrostatic deformable mirror described in (9), the reflective film 20 can be deformed into a curved surface.

  (10) In the case where the flexible reflective film is changed to a desired curvature, the substrate electrode and the thin plate member are arranged along a curve or straight line in which the displacement amount at each point of the reflective film is equal. The electrostatic deformable mirror according to any one of (5) to (9), wherein

(Corresponding embodiment)
The embodiment relating to the electrostatic deformable mirror described in (10) corresponds to the first embodiment.

(Function and effect)
In the electrostatic deformable mirror described in (10), the thin plate member 30 is arranged along the equal displacement line 100 where the displacement amount of the reflection film 20 becomes equal, and the thin plate member 30 on the same equal displacement line is arranged. Deform equally.

  Therefore, according to the electrostatic deformable mirror described in (10), a desired curvature can be easily obtained.

  (11) In the case where the flexible reflective film is changed to a desired curvature, the substrate electrode and the thin plate member, which are disposed at a site where it is not necessary to strictly control the curvature of the reflective film, Any of (5) to (10), wherein the substrate electrode and the thin plate-like member arranged at a portion where the curvature of the reflective film needs to be strictly controlled are arranged more densely The electrostatic deformable mirror described in 1.

(Corresponding embodiment)
The embodiment relating to the electrostatic deformable mirror described in (11) corresponds to the first embodiment.

(Function and effect)
In the electrostatic deformable mirror described in (11), in a state where the reflective film 20 is changed to a desired curvature, there are a portion where the curvature needs to be strictly controlled and a portion where the curvature is not necessary, The substrate electrode 40 and the thin plate member 30 are densely arranged with respect to a portion where the curvature needs to be strictly controlled.

  Therefore, according to the electrostatic deformable mirror described in (11), the curvature of the reflective film 20 can be controlled more strictly.

  (12) In the case where the flexible reflective film is changed to a desired curvature, the curvature of the reflective film is larger than that of the substrate electrode and the thin plate member disposed at a portion where the curvature of the reflective film is small. The electrostatic variable shape mirror according to any one of (5) to (10), wherein the substrate electrode and the thin plate-like member arranged in a large part are arranged more densely.

(Corresponding embodiment)
The embodiment relating to the electrostatic deformable mirror described in (12) corresponds to the first embodiment.

(Function and effect)
The curvature increases as the interval between the equal displacement lines 100 of the reflective film 20 decreases. When the curvature of the film is greatly deformed, the distortion increases and the force required for the deformation also increases. Therefore, in the electrostatic deformable mirror described in (12), the substrate electrode 40 and the thin plate member 30 are densely arranged in a portion having a large curvature, that is, a portion where the interval between the equal displacement lines 100 is narrow.

  Therefore, according to the electrostatic deformable mirror described in (12), the reflective film 20 can be set to a desired curvature.

  (13) The voltage value applied independently to each of the plurality of thin plate-like members is controlled, and the plurality of substrate electrodes are set to a common potential. Electrostatic deformable mirror.

(Corresponding embodiment)
The embodiment relating to the electrostatic deformable mirror described in (13) corresponds to the first embodiment.

(Function and effect)
In the electrostatic deformable mirror described in (13), all substrate electrodes 40 are connected to a common external lead electrode 60 and grounded, and each thin plate member 30 is connected to the external lead electrode 60. Thus, a voltage is applied independently.

  Therefore, according to the electrostatic deformable mirror described in (13), the amount of displacement of each thin plate member 30 can be controlled independently, so that the curvature of the reflective film 20 can be freely set, Multiple patterns can be set.

(14) dividing the plurality of thin plate-like members into groups having at least one group element of two or more,
The electrostatic variable shape mirror according to any one of (5) to (12), wherein a voltage value to be independently applied to each group is controlled and the plurality of substrate electrodes are set to a common potential. .

(Corresponding embodiment)
The embodiment relating to the electrostatic deformable mirror described in (14) corresponds to the first embodiment.

(Function and effect)
The electrostatic deformable mirror described in (14) divides the thin plate-like members 30-1 to 30-4 arranged along the equal displacement lines 100-1 to 100-4 into groups, respectively. The substrate electrode 40 is connected to the common external lead electrode 60 and grounded. Therefore, the thin plate-like members 30-1 to 30-4 divided into groups are connected to the external lead electrode 60 for each group, and a voltage is applied.

  Therefore, according to the electrostatic deformable mirror described in (14), the thin plate members belonging to each group can be deformed equally. Therefore, the thin plate members arranged along the same equal displacement line are used. The reflective film 20 can be easily set to a desired curvature by being easily deformed equally.

  (15) The voltage value applied independently to each of the plurality of substrate electrodes is controlled, and the plurality of thin plate-like members are set to a common potential. Electrostatic deformable mirror.

(Corresponding embodiment)
The embodiment relating to the electrostatic deformable mirror described in (15) corresponds to the first embodiment.

(Function and effect)
In the electrostatic deformable mirror described in (15), all thin plate members are connected to a common external lead electrode and grounded, and each substrate electrode is connected to the external lead electrode independently. Apply voltage.

  Therefore, according to the electrostatic deformable mirror described in (15), the amount of displacement of each thin plate member can be controlled independently, so that the curvature of the reflective film can be freely set, It can be set to a pattern.

(16) dividing the plurality of substrate electrodes into groups having at least one group element of two or more;
The electrostatic variable shape according to any one of (5) to (12), wherein the voltage value applied independently to each group is controlled, and the plurality of thin plate members are set to a common potential. mirror.

(Corresponding embodiment)
The embodiment relating to the electrostatic deformable mirror described in (16) corresponds to the first embodiment.

(Function and effect)
In the electrostatic deformable mirror described in (16), the substrate electrodes arranged along the equal displacement lines are divided into groups, and all the thin plate members are connected to a common external lead electrode. Is grounded. Therefore, the substrate electrodes divided into groups are connected to external lead electrodes for each group, and a voltage is applied.

  Therefore, according to the electrostatic deformable mirror described in (16), the thin plate-like members corresponding to the substrate electrodes belonging to each group can be deformed equally, so that they are arranged along the same equal displacement line. The thin plate member can be easily deformed equally, and the reflective film can be easily set to a desired curvature.

(A) is a perspective view for demonstrating the structure of the electrostatic deformable mirror which concerns on 1st Embodiment of this invention, (B) removes a reflecting film in the electrostatic deformable mirror of (A). FIG. It is a perspective view which expands and shows the board | substrate electrode and thin plate-shaped member in the electrostatic deformable mirror which concerns on 1st Embodiment. It is a figure which shows the other form of the board | substrate electrode in the electrostatic variable shape mirror which concerns on 1st Embodiment, and a thin plate-shaped member. (A) to (D) are cross-sectional views taken along the line AA of the electrostatic deformable mirror in FIG. 1 (A). In particular, (A) applies a voltage to all substrate electrodes and thin plate members. The figure which shows the initial state which is not, (B) is a figure which shows the case where the voltage value applied gradually between the board | substrate electrode arrange | positioned from the outer peripheral part to the center part and a thin plate-shaped member is made high, (C) is a center part It is a figure which shows the case where the voltage value applied gradually between the board | substrate electrode arrange | positioned from the outer peripheral part to a thin plate-shaped member is made high, (D) is a voltage between arbitrary board | substrate electrodes and a thin plate-shaped member. It is a figure which shows the applied state. (A) And (B) is a figure which expands and shows the junction part of a thin plate-shaped member and a reflecting film, in order to demonstrate the rigidity of the thin plate-shaped member and the reflecting film in the electrostatic deformable mirror which concerns on 1st Embodiment, respectively. In particular, (A) is a diagram showing a case where the rigidity of the thin plate member and the rigidity of the reflective film are moderately balanced, and (B) is a diagram showing the rigidity of the reflective film compared to the rigidity of the thin plate member. It is a figure which shows the case where it is extremely low. FIGS. 5A and 5B are top views for explaining examples of arrangement of substrate electrodes and thin plate members in a state where the reflective film of the electrostatic deformable mirror according to the first embodiment is changed to a desired curvature. FIG. (A) And (B) is the top view and sectional drawing for demonstrating the example of arrangement | positioning of a substrate electrode and a thin-plate-shaped member in the case of giving a circularly symmetrical curvature with respect to a perfect-circle reflective film, respectively. (A) And (B) is the top view and sectional drawing for demonstrating the example of arrangement | positioning of a board | substrate electrode and a thin-plate-shaped member, respectively, when giving a wave-front-shaped curvature with respect to a square reflecting film. It is a figure which extracts and shows the reflecting film and thin plate member for demonstrating the example of arrangement | positioning of a substrate electrode and a thin plate member in the case of dividing | segmenting a thin plate member or a substrate electrode into a some group. (A) is a top view of the electrostatic deformable mirror according to the second embodiment of the present invention, and (B) and (C) are cross sections taken along the line EE of the electrostatic deformable mirror of (A), respectively. FIG. (A) is a top view of the electrostatic deformable mirror according to the third embodiment of the present invention, and (B) is a sectional view taken along line FF of the electrostatic deformable mirror of (A).

Explanation of symbols

    DESCRIPTION OF SYMBOLS 10 ... Electrostatic type deformable mirror, 20 ... Reflective film, 30 ... Thin plate-like member, 31 ... Movable electrode extraction wiring, 40 ... Substrate electrode, 41 ... Substrate electrode extraction wiring, 50 ... Substrate, 60 ... External lead electrode, 70 ... Insulating film, 80 ... Contact hole, 90 ... Frame material, 100 ... Displacement line, 101 ... Level indicating the displacement of the thin plate member.

Claims (16)

In the electrostatic deformable mirror that changes the degree of convergence or divergence or deflection of the light incident on the reflective film by deforming the reflective film with flexibility by electrostatic force,
A substrate electrode disposed fixed to the substrate;
A thin plate-like member having conductivity disposed to face the substrate electrode;
Comprising
The thin plate member has a substrate connection portion fixed to the substrate and a reflection film connection portion bonded to the reflection film,
A voltage is applied between the substrate electrode and the thin plate member to change the shape of the thin plate member, thereby displacing the reflective film connecting portion in the direction of the substrate and changing the curvature of the reflective film. An electrostatic deformable mirror characterized by that.   2. The electrostatic deformable mirror according to claim 1, wherein the reflective film having flexibility is supported by a frame material.   3. The electrostatic deformable mirror according to claim 1, wherein the flexibility of the reflective film is substantially equal to the rigidity of the thin plate member.   3. The electrostatic deformable mirror according to claim 1, wherein a rigidity of the flexible reflective film is in a range of 0.5 to 1.5 times that of the thin plate member. .   The electrostatic deformable mirror according to claim 1, wherein a plurality of the substrate electrodes and the thin plate-like members are arranged.   6. The electrostatic deformable mirror according to claim 5, wherein the reflective film having flexibility is supported by the thin plate member.   6. The electrostatic deformable mirror according to claim 5, wherein the flexible reflective film is supported by a frame material.   8. The electrostatic deformable mirror according to claim 5, wherein the flexible reflective film has a rigidity substantially equal to that of the thin plate member.   8. The electrostatic type according to claim 5, wherein the flexible reflective film has a rigidity in a range of 0.5 to 1.5 times that of the thin plate member. Deformable mirror.   In the case of changing the flexible reflective film to a desired curvature, the substrate electrode and the thin plate member are arranged along a curve or a straight line in which the amount of displacement at each point of the reflective film is equal. 10. The electrostatic deformable mirror according to claim 5, wherein the electrostatic deformable mirror is used.   In the case where the flexible reflective film is changed to a desired curvature, the reflective film is disposed on the substrate electrode and the thin plate-like member, which are disposed at portions where it is not necessary to strictly control the curvature of the reflective film. 11. The electrostatic according to claim 5, wherein the substrate electrode and the thin plate-like member arranged in a portion where the curvature of the substrate needs to be strictly controlled are arranged more densely. Type deformable mirror.   In the case where the flexible reflective film is changed to a desired curvature, the reflective film has a large curvature with respect to the substrate electrode and the thin plate-like member, which are disposed at a small curvature of the reflective film. The electrostatic deformable mirror according to claim 5, wherein the substrate electrodes and the thin plate-like members that are arranged are arranged more densely.   The electrostatic variable according to any one of claims 5 to 12, wherein a voltage value applied independently to each of the plurality of thin plate members is controlled, and the plurality of substrate electrodes are set to a common potential. Shape mirror. Dividing the plurality of thin plate-like members into groups having at least one group element of two or more,
13. The electrostatic deformable mirror according to claim 5, wherein a voltage value to be independently applied to each group is controlled and the plurality of substrate electrodes are set to a common potential.   The electrostatic variable according to any one of claims 5 to 12, wherein a voltage value applied independently to each of the plurality of substrate electrodes is controlled, and the plurality of thin plate members are set to a common potential. Shape mirror. Dividing the plurality of substrate electrodes into groups having at least one group element of two or more;
13. The electrostatic deformable mirror according to claim 5, wherein a voltage value to be independently applied to each group is controlled and the plurality of thin plate members are set to a common potential.

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