JPS63215275A - Slight displacement device for solid-state pickup device - Google Patents

Abstract

PURPOSE:To attain slight displacement independently in two directions by forming a stuck piezoelectric vibrator of cantilever structure and a stuck piezoelectric vibrator of both-end support structure within the same plane. CONSTITUTION:Piezoelectric plates (8a, 8b)-(11a, 11b) where polarized axes are provided in the broadwise direction on upper and lower faces of a rectangular metallic thin plate 7 and electrodes are arranged on the upper and lower faces are stuck so that the direction of polarization axis is identical to constitute independent stuck piezoelectric vibrators 8-11. The middle part of the stuck piezoelectric vibrators 10, 11 is fixed and supported on a base 12 by using fixed members 13a, 13b and a mobile base 15 is fitted with a packaged solid- stage image pickup element 14 placed on the middle part of the stuck piezoelectric vibrators 8, 9. Since the stuck piezoelectric vibrators 8, 9 and 10, 11 are driven independently, the solid-state image pickup element 14 is displaced in two directions on the same plane.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a micro-displacement device for a solid-state image sensor for precise positioning in two directions on the same plane. This device is
It can be used for alignment of color solid-state image sensors of video cameras, displacement devices for high-resolution solid-state image sensors, etc.

Conventional technology Positioning by micron or submicron displacements has conventionally been performed by mechanical means, using stepping motors or DC servo motors, and converting rotational motion into linear motion by twisting the pole. For this reason, in order to improve accuracy without eliminating errors caused by mechanical coupling, the device must become larger.

Therefore, a micro-displacement device using the inverse piezoelectric effect of a piezoelectric element that can be electrically controlled was devised, and
There is an insect type movement mechanism as shown in Japanese Patent No. 97. FIG. 3 is an explanatory diagram of the above-mentioned insect-shaped moving mechanism, which has a structure in which clamp elements 2.3 using electrostatic force or electromagnetic force are attached to both ends of the cylindrical piezoelectric element 1. In the same figure (a), the clamp element 2.3 is clamped to the fixed base 4, in the same figure (b), the clamp element 3 is made free, and in the same figure (c), a voltage is applied to the piezoelectric element 1, and the piezoelectric element 1 is growing. In the same figure (d), the clamp element 3 is clamped to the fixed base 4 again in the extended state, the clamp element 2 is made free in the same figure (e), the applied voltage is removed in the same figure (f), and the same figure In (g), the clamp element 2 is clamped again. This results in the same state as in FIG. 2(a), with a displacement of Δe. By attaching the moving mechanism in two directions, a two-direction minute displacement device can be easily obtained. Since the strain caused by the inverse piezoelectric effect is small, highly accurate positioning is possible.

Also, Japanese Patent Publication No. 58-130677, No. 58-19
Publication No. 6773 describes a method using a bending vibrator (bimorph vibrator) in which a rectangular piezoelectric element having a polarization axis in the thickness direction is bonded to the upper and lower surfaces of a thin metal plate of the same shape, and one end is fixed or both ends are fixed. A displacement device for a solid-state image sensor has been disclosed which increases the light-receiving area by displacing the solid-state image sensor and achieves higher resolution. FIG. 4 shows one example of a unidirectional minute displacement device using the bending vibrator. A bending vibrator 5.5'' with both ends fixed is arranged in parallel, and a movable table 6 is provided on which a solid-state imaging device or the like is placed at the center position of the bending vibrator 5.5'' where the amount of displacement is maximum.

Problems to be Solved by the Invention By attaching the above-mentioned insect-like micro-displacement device in two directions on the same surface, it is easy to create a two-direction micro-displacement device. Because it must be clamped using electromagnetic force, devices that are portable or tilted require additional fixing of objects that move when not in operation, making the structure complex and the device larger. Additionally, when moving, the weight of the moving object concentrates on the part where the clamp is removed, making it mechanically unstable. Furthermore, the direction of movement is determined by the attachment of the device, and the attachment cannot be moved later in any direction.

In the case of a micro-displacement device using a bending vibrator, the amount of strain is large (it can be removed), but the generated force is weak (it cannot move heavy objects. Also, when a large load is applied, the resonant frequency of the vibrator decreases. , the harmonic components of the drive frequency tend to cause resonance, causing problems in durability.Therefore, in order to make a minute displacement device in any direction, a displacement device (first displacement unit) using the bending vibrator, It is possible to displace another displacement device (second displacement unit), but since the weight of the second displacement unit is applied to the first displacement unit, in order to reduce the influence of the weight of the second displacement unit, the first It is necessary to enlarge the bending vibrator of the displacement unit, resulting in an increase in size.Also, a problem arises in durability.

Means for solving the problem: Two plate-shaped piezoelectric elements with polarization axes in the thickness direction and electrodes arranged on the top and bottom surfaces on both sides of each side of a rectangular thin metal plate made to be square. are bonded together so that their polarization axes are in the same direction to form mutually independent bonded piezoelectric vibrators.
The center portions of the pair of bonded piezoelectric vibrators facing each other are fixedly supported by a fixing member made of an insulating material such as resin-coated metal or resin, and the center portions of the other pair of bonded piezoelectric vibrators facing each other are fixedly supported. A movable stage with an image pickup element attached thereto is provided, the upper and lower surface electrodes of the bonded piezoelectric vibrators are electrically connected to each other as one independent applied voltage terminal, and the thin metal plate is connected to a common terminal for all of the bonded piezoelectric vibrators. Using a flexible substrate configured as an applied voltage terminal and bonded to the bottom surface of the moving table, the signal of the solid-state image sensor and the applied voltage terminal of the bonded piezoelectric vibrator are drawn out to the outside, and the piezoelectric vibrator is By independently driving the solid-state image sensor, it is possible to independently slightly displace the solid-state image sensor in two directions on the same plane.

Effect When voltage is applied to the applied voltage terminals of the upper and lower electrodes of the bonded piezoelectric vibrator and the applied voltage terminals of the thin metal plate, one side of the bonded plate-shaped piezoelectric elements expands and the other contracts, resulting in bending vibration. It acts as a bending oscillator. The bonded piezoelectric vibrator whose center part is fixed becomes a bending vibrator with a cantilevered structure on both sides of the fixed part, and the bonded piezoelectric vibrator itself with the movable stage attached is attached to the electrode surface of the cantilever structure bending vibrator. On the other hand, it can be displaced in the normal direction.

The bonded piezoelectric vibrator with a movable stage attached to the center is a bending vibrator having a structure in which both ends are fixedly supported, and the movable base with the solid-state imaging device attached can be displaced in the direction normal to the electrode surface. As a result, the micro-displacement device that independently displaces the solid-state image sensor in two directions can be miniaturized and has a simple structure.

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an embodiment of the present invention; FIG. 1(a) is a perspective view, FIG. 1(b) is an exploded perspective view, and FIG. 1(c) is an exploded perspective view showing a bonded piezoelectric vibrator. be. As shown in FIG. 1(c), plate-shaped piezoelectric elements (8a, 8 b), (9a, 9b)
, (10a, 10b), (lla, 11
b) are bonded together so that their respective polarization axes directions are the same, thereby forming mutually independent bonded piezoelectric vibrators 8, 9, and 10.
．． It consists of 11. Laminated piezoelectric vibrator 10.1
The center portion of the piezoelectric vibrator 1 is fixedly supported on the base 12 by adhesive or the like using fixing members 13a and 13b made of resin-coated metal or resin, etc., and the bonded piezoelectric vibrators 8 and 9 are assembled.
A moving table 15 on which a packaged solid-state image sensor 14 is mounted is attached to the center of the screen. The upper and lower surface electrodes of the bonded piezoelectric vibrators 8, 9, 10, and 11 are electrically connected to apply voltage terminals 16, 17, and 18, 19, and the thin metal plate 7 is connected to the applied voltage terminals 16, 17, and 18, 19. A common applied voltage terminal 20 is used. A flexible substrate 21 is attached to the bottom of the moving table 15, and signals from the solid-state image sensor 15 and signals to the applied voltage terminals 16, 17, 18, and 19 of the bonded piezoelectric vibrators 8.9, 10.11 are wired. Base 1
It is connected to a printed circuit board 22 attached to the bottom surface of 2. Further, a common applied voltage terminal 20 is electrically connected to the base 12 and connected to a printed circuit board 22. By applying a voltage to the applied voltage terminals 20 and 16.17, the bonded piezoelectric vibrator 8.9 functions as a bending vibrator with a support structure at both ends, and is displaced in the direction normal to the electrode surface. The amount of displacement is proportional to the applied electric field and the piezoelectric constant da+. The thicknesses of the piezoelectric elements 8a, 8b, 9a, and 9b to be bonded are the same,
If the directions of polarization axes of the bonded piezoelectric vibrators 8 and 9 facing each other are the same, the same phase and the same voltage are applied, the displacement amount and displacement direction of the bonded piezoelectric vibrators 8 and 9 are the same, and the piezoelectric vibrators 8 and 9 are attached in the center. The piezoelectric vibrator 8 is attached to the moving table 15,
9, that is, in the direction normal to the electrode surface. The bonded piezoelectric vibrator 10°11 whose central portion is fixedly supported by fixing members 13a and 13b is as follows:
It functions as a bending vibrator with a cantilevered structure, and the applied voltage terminal 2
When voltage is applied to 0 and 18.19 so that the displacement amount and displacement direction are the same, the bonded piezoelectric vibrators 8 and 9 are moved in the same direction as the displacement direction, that is, with respect to the electrode surface of the piezoelectric vibrator 10.11. Since it is displaced in the normal direction, the moving table 15 is also displaced in the same direction. Since the bonded piezoelectric vibrators 8.9 and 10.11 can be driven independently, the movable stage 15, that is, the solid-state image sensor 14 can be displaced in two directions on the same plane.

Further, since the bonded piezoelectric vibrators 8.9 and 10.11 are arranged on the same plane, the device can be miniaturized as an independent minute displacement device in two directions, and the structure can be simplified.

The advantage of further miniaturization is that a solid-state image pickup device, rather than an image pickup tube, can be attached to a prism used in a three-tube video camera or the like in three directions in a state where the position can be adjusted.

Next, other embodiments of the present invention will be described.

FIG. 2 is an exploded perspective view of a bonded piezoelectric vibrator showing another embodiment of the present invention. The rectangular thin metal plates 7a and 7b bent in a U-shape are placed facing each other to form a rectangular rectangular thin metal plate. Piezoelectric elements (10a, 10b), (lla, 1
1b). When manufacturing the thin metal plates 7a and 7b, there is only one bending direction, and the structure is suitable for mass production.

Since the bonded piezoelectric vibrator with a cantilevered structure and the bonded piezoelectric vibrator with a support structure at both ends are connected through a thin metal plate, it is inevitable that they will be affected by each other, but as shown in Figure 1 (C). As shown, there is a U-shaped recess 23 a in the thin metal plates on both sides of the bonded piezoelectric vibrator with a support structure at both ends!
By providing 23 b + 23 c and 23 d or by providing a hole, the bending rigidity is increased (thus reducing the influence and improving reliability).

Effects of the Invention According to the present invention, by configuring a cantilever-structured bonded piezoelectric vibrator and a bonded piezoelectric vibrator with a both-end support structure in the same plane, micro displacements can be made independently in two directions. As a result, the device can be miniaturized as a minute displacement device that is independent in two directions, and has a simple structure.

[Brief explanation of the drawing]

FIG. 1 shows a two-direction minute displacement device according to an embodiment of the present invention, FIG. 1(a) is a perspective view thereof, FIG. 1(b) is an exploded perspective view,
FIG. 2(c) is an exploded perspective view showing a bonded piezoelectric vibrator, which is a main part thereof, and FIG. Figures 3 and 44 are a front view and a perspective view, respectively, of a conventional micro-displacement device. 7... Metal thin plate, 8,9.10.11... Bonded piezoelectric vibrator, 8a, 8b, 9a, 9b, 10a, 10
'b, 11a, 1 lb, . . . piezoelectric element, 12-.
- Base, 13a, 13b... Fixed member, 14... Solid-state image sensor, 15... Moving table, 21... Flexible substrate. Name of agent: Patent attorney Toshio Nakao and one other person Figure 1 Figure 1 (b) Figure 2 W Figure 3 Figure 4

Claims (3)

[Claims] (1) Two plate-shaped piezoelectric elements with polarization axes in the thickness direction and electrodes arranged on the top and bottom surfaces are placed on both sides of each side of a rectangular thin metal plate, so that the polarization axes are in the same direction. The bonded piezoelectric vibrators are bonded together to form a bonded piezoelectric vibrator, and the center portions of the pair of bonded piezoelectric vibrators facing each other are fixedly supported by a fixing member made of an insulating material, and A movable stage with a solid-state imaging device attached to the center is provided, and the upper and lower surface electrodes of the bonded piezoelectric vibrator are electrically connected to each other as one independent applied voltage terminal, and the metal thin plate is connected to the bonded piezoelectric vibrator as a whole. The signals of the solid-state image sensor and the applied voltage terminal of the bonded piezoelectric vibrator are drawn out to the outside by using a flexible substrate bonded to the bottom surface of the moving table. A micro-displacement device for solid-state imaging devices characterized by: (2) A rectangular rectangular thin metal plate is constructed by using two rectangular thin metal plates bent in a U-shape, and both ends of the two thin metal plates are fixedly supported by a fixing member at the center. 2. The micro-displacement device for a solid-state image pickup device according to claim 1, wherein the micro-displacement device is configured to be located at a central fixed portion of the bonded piezoelectric vibrator. (3) A micro-displacement device for a solid-state image sensor according to claim 1, characterized in that the bending rigidity of the thin metal plate at both ends of the bonded piezoelectric vibrator to which the moving stage is attached is increased. .