JPH10145663A - Electronic camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic camera with small size, light weight and suitable for power-saving by providing a mechanism to prevent or to reduce instability in a picked-up image caused by the movement of the electronic camera especially (typically so-called shaking). SOLUTION: The camera is provided with a lens system 1, a solid-state image pickup device 21 to detect a light made incident through the lens system and provided to a moving stage 31, an image pickup device moving means 5 moving the moving stage 31 in a prescribed direction with respect to a base 1, and a control means 6 to drive the image pickup device moving means 5, and also with a motion sensor 7 to sense a motion of an electronic camera 200 and the control means 6 drives the image pickup device moving means 5 so as to prevent or reduce the instability in the picked-up image resulting from a motion of the electronic camera 200 in response to a signal from the motion sensor 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic camera capable of appropriately photographing a subject, and more particularly, to a method in which a shake (typically, a so-called "hand shake") of a photographed image caused by a movement of the electronic camera does not occur or The present invention relates to an electronic camera having a mechanism for reducing the size and suitable for miniaturization, weight reduction, and power saving.

[0002]

2. Description of the Related Art Various methods have been conventionally proposed for correcting camera shake of electronic still cameras and electronic movie cameras (these cameras are collectively referred to as “electronic cameras”). , VOL.49, N
o. 2, 131-134 (1995)). Generally, the camera shake correction mechanism is realized by a camera shake detection unit and a camera shake correction unit. As each means, a mechanical type and an electronic type are known. In a camera shake correction mechanism that is currently considered to have the best performance, both a camera shake detection unit and a camera shake correction unit are of a mechanical system.

The mechanical image stabilization means includes a gimbal mechanism method for performing correction by moving a lens system (see ref. 1 in the above-mentioned academic journal) and a correction optical system utilizing a specific lens for correction (for example, ref. 1). A variable apex prism method (see ref. 6 and 10 in the above-mentioned academic journal) in which a prism is rotated to perform correction is known (see “Electronics”, published by Nikkei BP, July 1994, page 31). .
Each of these methods has the advantage that the resolution does not decrease and the correction range is wide.

However, when a gimbal mechanism system or a system using a correction optical system is adopted as the camera shake correction means, as described above, the drive mechanism for moving the entire lens system or a specific lens becomes large and heavy. Therefore, the size and weight of the electronic camera itself are increased, the power consumption is increased, and the portability of the electronic camera is impaired. Further, in the variable apex angle prism system, since the driving mechanism is relatively small, the above-described problems such as the increase in size and weight of the electronic camera itself are alleviated, but the mechanism becomes complicated and the cost increases. There's a problem.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a high-performance camera shake correction without deteriorating the advantages of the prior art, such as a reduction in resolution and a wide correction range, suitable for miniaturization, weight reduction, and power saving. It is to provide an electronic camera at low cost. Another object of the present invention is to provide an electronic camera capable of shooting without shaking even when shaking due to a cause other than camera shake, for example, shaking caused by the subject being shaken occurs. is there. Still another object of the present invention is to provide an electronic camera capable of performing fine adjustment at the time of focusing without moving a lens system at low cost.

[0006]

SUMMARY OF THE INVENTION An electronic camera (including both a still camera and a movie camera) according to the present invention includes (1) a lens system, and (2) a solid state provided on a movable stage for detecting light incident through the lens system. Imaging device, (3)
A predetermined movement of the movable stage with respect to the base (for example, a movement in a direction parallel to and / or perpendicular to the light receiving surface of the solid-state imaging device, a rotational movement about an axis perpendicular to the light receiving surface) is performed. Imaging device moving means, (4)
Control means for driving the imaging device moving means,
It is characterized by having.

[0007] That is, in the present invention, camera shake correction, focusing, and the like are performed by making the solid-state imaging device movable. This eliminates the need to move the entire lens system or a specific lens as in a conventional electronic camera. The amount of work required to move the solid-state imaging device is extremely small as compared with the amount of work to move a lens system or a specific lens. In addition, since the solid-state imaging device is lighter than a lens, position control can be performed at high speed and with high accuracy when moving the solid-state imaging device, and the imaging device moving means can be downsized.

Further, the electronic camera of the present invention has the above (1).
In addition to (4), (5) a motion sensor for detecting a motion of the electronic camera such as camera shake (hereinafter referred to as "camera shake") is provided, and the control means responds to a signal from the motion sensor. Then, the imaging device moving means is driven so that the shake of the captured image due to the camera shake does not occur or becomes small.

When the electronic camera of the present invention is used for camera shake correction, camera shake can be corrected at high speed and with high accuracy by configuring the electronic camera as follows. That is, the movable stage can be moved in a direction parallel to the light receiving surface of the solid-state imaging device by the imaging device moving means (rotational movement around an axis perpendicular to the light receiving surface may be included). . In addition, one axis parallel to the light receiving surface by the motion sensor (usually a vertical center axis of the electronic camera when the electronic camera is held)
, The angular velocity of rotation of the electronic camera itself is detected. Then, the control means moves the movable stage parallel to the light receiving surface so that the photographing range of the electronic camera itself does not change before and after the rotation occurs, according to the angular velocity detection value obtained by the camera shake detection means. In the direction to perform camera shake correction. This makes it possible to provide a low-cost electronic camera capable of correcting camera shake with high performance and suitable for miniaturization, weight reduction, and power saving.

[0010] The imaging device moving means may be a mechanism using various forces such as piezoelectric force, electrostatic force, and electromagnetic force. If a particularly large driving force is desired, a mechanism using an electromagnetic force is preferable. In the present invention, by providing the magnetic field generating means on both the movable stage side and the base side, the movable stage can be moved using attractive force and repulsive force. That is, the imaging device moving means is constituted by a first magnetic field generating means provided on the movable stage side and a second magnetic field generating means provided on the base side, and these first and second magnetic field generating means are provided. The movable stage can be moved relative to the base by the interaction between the means.

For example, the first magnetic field generating means can be an electromagnet using a conductor coil, and the second magnetic field generating means can be a permanent magnet. For the movement of the movable stage, the set of the first magnetic field generating means and the second magnetic field generating means may be a single set. When the movable stage is moved in a certain direction, a plurality of sets of the first magnetic field generating means and the second magnetic field generating means can be provided. In the electronic camera of the present invention, the imaging device moving means is not limited to the above-described configuration. For example, a magnetic field generating means composed of a conductor coil is provided only on one of the movable stage side and the base side, and the other is a magnetic film. (Or a layer) may be formed, and the movable stage may be moved relative to the base by the interaction between the conductor coil and the magnetic film.

In the present invention, first and second position detecting electrodes are formed on the movable stage side and the base side, respectively, and an electrostatic force between the first and second position detecting electrodes is formed between the first and second position detecting electrodes. The position of the solid-state imaging device with respect to the base can be detected with high accuracy by detecting a change in the capacitance by the stage position detecting means.

In the present invention, the movable stage can be connected to the base via an elastic spring. By using this elastic spring, the movable stage can be held on the base side in a preloaded state. This elastic spring can be formed from the same substrate as the movable stage. Further, a signal line from a solid-state imaging device and a signal line from a position detection electrode formed on the movable stage side can be formed on the elastic spring.

Further, the electronic camera of the present invention is not limited to the use of camera shake correction. For example, when photographing a vibrating subject, the movable stage is vibrated in synchronization with the subject, so that the subject and the solid-state imaging device are relatively stationary, so that clear (that is, vibration is reduced). (Very small or very small). In the electronic camera of the present invention, the movable stage can be moved in a direction perpendicular to the light receiving surface of the solid-state imaging device. By doing so, fine focusing can be performed together with or instead of focusing by the lens system.

[0015]

FIG. 1 is a diagram showing an embodiment of an electronic camera according to the present invention. In FIG. 1, an electronic camera (in this embodiment,
The still camera 200 includes a lens system 1, a solid-state imaging device 21, a movable stage 31, a base 41, an imaging device moving unit 5, a control unit 6, a motion sensor 7, and a stage position detecting unit 8.

The lens system 1 is composed of a plurality of lenses. In FIG. 1, for convenience, one lens is shown.
The solid-state imaging device 21 is provided on the movable stage 31 and detects light from the subject 100 that has entered through the lens system 1. As the solid-state imaging device 21, a CCD, a MOS image sensor, or the like generally used for an electronic camera can be used.

The imaging device moving means 5 can move the movable stage 31 with respect to the base 41 in the positive and negative directions of the X axis and the positive and negative directions of the Y axis. FIG. 1 shows a state in which the electronic camera is viewed from above. The imaging device moving means 5 is provided in two or more sets in each of the X-axis direction and the Y-axis direction (only one pair is shown in the X-axis direction in FIG. 1 for convenience of explanation).
It can move in a two-dimensional direction parallel to. The imaging device moving means 5 can be constituted by a first magnetic field generating means and a second magnetic field generating means, as described later in FIGS.

The motion sensor 7 detects the motion of the solid-state imaging device. In FIG. 1, the motion sensor 7 is a camera shake detection unit that detects the rotational speed of the electronic camera about the X axis, the Y axis, and the θ axis (that is, in FIG. 1, the motion sensor 7 is an angular velocity sensor 7X, 7Y, 7θ). Is composed of). It is preferable to use a piezoelectric vibrating gyroscope as the angular velocity sensors 7X, 7Y, 7θ. The stage position detecting means 8 can receive signals from the first and second position detecting electrodes 81 and 82 and detect the position of the movable stage 31. The angular velocity sensors 7X, 7Y, 7θ are X
Angular velocity due to rotation about the axis, the Y axis, and the θ axis is detected and sent to the control means 6. The control means 6 includes an angular velocity sensor 7
In response to the angular velocity detection signals from X, 7Y, and 7θ and the stage position signal from the stage position detection unit 8, when the imaging range is about to change due to the rotation of the electronic camera itself, the imaging device moving unit 5 The movable stage 3 is mounted so that the photographing range does not change before and after the rotation occurs.
1 is moved in a direction parallel to the light receiving surface 22 to thereby perform camera shake correction. In FIG. 1, the control means 6
Is indicated by the comparator 61 and the feedback system 62.

For example, in FIG. 1, when the electronic camera rotates in the direction of arrow α, the subject moves to the right in the viewfinder of the electronic camera. Therefore, the control unit 6 controls the position of the subject projected on the light receiving surface 22 of the solid-state imaging device to coincide with the position of the subject projected on the light receiving surface 22 before the rotation of the electronic camera.
The camera shake correction is performed by driving the imaging device moving means 5. When detecting the angular velocity of rotation about the θ axis, the imaging device moving means 5 is configured to be able to rotate the light receiving surface 22 in the plane.

Usually, when the operator holds the electronic camera, the camera shake is caused by rotating the electronic camera around the Y-axis direction. Therefore, only for the Y-axis, the angular velocity due to the rotation is detected and the camera shake is corrected. Can also be performed. In this case, the movable stage 31 is configured to be movable in a one-dimensional direction (X-axis direction) parallel to the light receiving surface 22 of the solid-state imaging device 21.

In the above embodiment, the case where the electronic camera is a still camera is described. However, the configuration shown in FIG. 1 can be applied to a movie electronic camera. In a movie electronic camera, for example, when panning, the electronic camera itself rotates. In such a case, a change corresponding to the angular velocity with respect to the Y axis (or the Y axis and the X axis, and further, the θ axis) is monitored by means corresponding to the control means 6 in FIG. If the threshold is exceeded,
When the angular acceleration is a value other than zero (or when the angular acceleration exceeds a predetermined threshold value), the same camera shake correction as described above can be performed.

FIG. 2 is a sectional view showing in detail the mechanism of the digital camera shown in FIG. FIG. 3 shows the printed wiring board 4
2 and a connector 44 (to be described later), FIG. 4 is a plan view of the movable stage 31, the elastic springs 46A to 46L, and the elastic spring connector 43 (to be described later), and FIG. FIG. 6 shows a plan view of the printed wiring board 33 (described later), and FIG. 7 shows a perspective view of the elastic spring. 3 to 6, the line AA corresponds to the cross section of FIG.

Hereinafter, FIG. 2 will be described with reference to FIGS.
The explanation will proceed. In FIG. 2, a base (for example,
A rectangular printed wiring board 42 is formed on an aluminum (made of aluminum) 41. On the printed wiring board 42, second rectangular electrodes for position detection (82A to 82F, 82A and 82B in FIG.
Only shown). Electrodes 82A and 82B,
The electrodes 82C and 82D and the electrodes 82E and 82F are arranged with a gap therebetween. The direction of the gap is the electrode 82A
And 82B and electrodes 82E and 82F face the Y-axis direction,
The electrodes 82C and 82D face the X-axis direction. These electrodes 82A to 82F are connected to the connector 44 via wiring formed on the surface of the printed wiring board 42. The first position detection electrode will be described later.

A frame-shaped elastic spring connection portion 43 (see FIG. 4) is provided around the printed wiring board 42 with a spacer 45 interposed therebetween. A rectangular movable stage (also functioning as a printed wiring board) 31 as shown in FIG. 4 is arranged on the printed wiring board 42 with a small gap (for example, about 300 μm) from the surface of the printed wiring board 42. ing. The movable stage 31 includes an elastic spring connection portion 43.
, And a first position detection electrode (81A to 81C, but only 81A is shown in FIG. 2) is formed on the lower surface thereof. Electrodes 81A are electrodes 82A and 82
The electrode 81B is formed directly above the electrodes 82C and 82D, and the electrode 81C is formed directly above the electrodes 82E and 82F. One set of these three electrodes [8
1A, 82A, 82B], electrodes [81B, 82C, 82]
D] and the electrodes [81C, 82E, 82F] each constitute a capacitance bridge.

The electrodes 81A to 81C are connected to the ball pads P formed on the surface of the movable stage 31 through the through holes S as shown in FIG. In addition, the ball pad P is formed of a ball of the ball grid array 35A, a printed wiring board 32, a ball of the ball grid array 35B, a through hole S of the printed wiring board 33, and wiring formed on the surface of the printed wiring board 33, which will be described later. Via a connector 34 described later.

The signals from the electrodes 81A to 81C are sent to the stage position detecting means 8 shown in FIG. 1 via the connector 34, and the signals from the electrodes 82A to 82F are sent via the connector 44. The first position detection electrodes 81A to 81A
The amount of movement of the movable stage 31 with respect to the base 41 (that is, the position of the solid-state imaging device 21 described later) can be detected by 81C and the second position detection electrodes 82A to 82F.

The movable stage 31 and the elastic spring connection part 4
4, a plurality of (here, three) elastic springs (46A to 46A) are provided for each side as shown in FIG.
L, but only 46A and 46I are shown in FIG. 2). As a result, the movable stage 31 is
Is held in. The elastic springs 46A to 46L are
As shown in FIG. 7, it is preferable to make the shape hard to move in a direction other than the direction of expansion and contraction.
The spring height b is 1 mm, and the spring width a is 30 μm.
By configuring the elastic springs 46A to 46L in this manner,
The minute gap between the movable stage 31 and the printed wiring board 42 can be kept constant. In addition, since the movable stage 3 can be preloaded, correction can be performed with a small amount of power, and the movable stage 31 can operate stably.
Can be moved.

In this embodiment, the elastic springs 46A to 46L
The movable stage 31 and the elastic spring connection portion 43 are formed of the same substrate, and the spacer 45 is provided to form a minute gap between the movable stage 31 and the printed wiring board 42. Note that both ends of the elastic springs 46A to 46L created by an appropriate method can be attached to the movable stage 31 and the elastic spring connection portion 43. Also,
In the present embodiment, no wiring is formed on the elastic springs 46A to 46L, but wiring from the solid-state imaging device 21 or the like described below can be formed on the elastic spring.

At the center of the movable stage 31, a solid-state imaging device 21 is provided. Wiring from the solid-state imaging device 21 is connected to a bonding pad 24 formed on the movable stage 31 via a bonding wire 23.
It is connected to the. The bonding pad 24 is connected to a ball pad P formed on the movable stage 31. A printed wiring board 32 having a rectangular frame shape as shown in FIG. 5 is provided around the movable stage 31. A ball pad P formed on the movable stage 31 and a back surface of the printed wiring board 32 are provided. Are connected to each other through a ball grid array 35A. Note that a through hole is formed in the printed wiring board 32, and a through hole is formed on the back surface of the printed wiring board 32.
The ball pad P is connected to the ball pad P formed on the surface thereof.

On the printed wiring board 32, there is formed a printed wiring board 33 for a coil having a rectangular frame shape whose periphery protrudes like an eave. As shown in FIG. 6, the four corners of the protruding eaves on the printed wiring board 33 are
(The coils 51A to 51F, but only 51A and 51E are shown in FIG. 2). Here, one ends of the coils 51A and 51E are connected to each other on the back surface thereof through through holes formed in the printed wiring board 32, and the other ends of the coils 51A and 51E are connected to the through holes formed in the printed wiring board 32. Through Hall S,
Another through hole S formed on the surface of the printed wiring board 32 leads to the printed wiring formed on the back surface.
Through the printed wiring formed on the surface thereof. Similarly,
The coils 51B and 51D and the coils 51C and 51F also have one ends connected to each other, and the other ends connected to the connector 3.
4 is connected. A signal from the control means 6 described in FIG.
The moving stage 31 can be moved to a desired direction (moving in the X-axis and Y-axis directions or rotating around the θ-axis).

Further, as shown in FIG. 6, a second magnetic field generating means having a U-shaped cross section (permanent magnets 52A to 52F, but only 52A and 52E are shown) having magnetic poles formed at opposing portions is provided with printed wiring. The coils 51A to 51 of the plate 33
It is fixed to the base 41 side so as to sandwich the portion where the F is formed. The coils 51A and 51E are
When a current is passed, the pattern is formed such that one direction is to increase the magnetic flux density in the slit of the permanent magnet, and the other direction is to decrease the magnetic flux density of the permanent magnet.
Similarly, with respect to the coils 51B and 51D and the coils 51C and 51F, when a current is passed, one direction increases the magnetic flux density in the slit of the permanent magnet, and the other direction decreases the magnetic flux density of the permanent magnet. The pattern is formed as follows.

[0032]

The present invention is configured as described above.
An electronic camera capable of correcting camera shake with high performance and suitable for miniaturization, weight reduction, and power saving can be provided at low cost. Further, it is possible to provide at low cost an electronic camera suitable for miniaturization, weight reduction, and power saving, capable of performing appropriate photographing even when it is conventionally difficult to appropriately photograph a subject due to causes other than camera shake.

[Brief description of the drawings]

FIG. 1 is a diagram showing one embodiment of an electronic camera of the present invention.

FIG. 2 is a cross-sectional view showing a mechanism of the electronic camera of the present invention shown in FIG. 1 in detail.

FIG. 3 is an explanatory plan view of a printed wiring board and a connector formed on a base in the present invention.

FIG. 4 is an explanatory plan view of a movable stage, an elastic spring, and an elastic spring connection portion in the present invention.

FIG. 5 is an explanatory plan view of a printed wiring board formed around a movable stage in the present invention.

FIG. 6 is an explanatory plan view of a printed wiring board on which first magnetic field generating means is formed according to the present invention.

FIG. 7 is a perspective view of an elastic spring according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 lens system 21 solid-state imaging device 22 light receiving surface 23 bonding wire 24 bonding pad 31 movable stage 32, 33 printed wiring board 34 connector 35A, 35B ball grid array 41 base 42 printed wiring board 43 elastic spring connection part 44 connector 45 spacer 46A To 46L elastic spring 5 imaging device moving means 51A to 51F first magnetic field generating means (coil) 52A to 52F second magnetic field generating means (permanent magnet) 6 control means 7 motion sensor 7X, 7Y, 7θ angular velocity sensor 8 stage position Detecting means 81A to 81C First position detecting electrodes 82A to 82F Second position detecting electrodes 100 Subject 200 Electronic camera S Through hole P Ball pad

Claims (8)

[Claims] A lens system; a solid-state imaging device provided on a movable stage for detecting light incident through the lens system; an imaging device moving means for moving the movable stage with respect to a base; Control means for driving the device moving means,
An electronic camera comprising: 2. The electronic camera according to claim 1, further comprising a motion sensor for detecting a motion of the electronic camera, wherein the control unit moves the electronic camera in response to a signal from the motion sensor. An electronic camera characterized in that the imaging device moving means is driven so that a shake of a captured image caused by the image generation does not occur or becomes small. 3. The electronic camera according to claim 2, wherein said imaging device moving means has a mechanism for moving said movable stage in a direction parallel to a light receiving surface of said solid-state imaging device, and said movement. The sensor has a mechanism for detecting the angular velocity of rotation of at least the vertical center axis of the electronic camera, and the control unit controls the electronic camera according to an angular velocity detection value obtained by the camera shake detection unit to determine a shooting range of the electronic camera. An electronic camera, wherein the movable stage is moved in a direction parallel to the light receiving surface so as not to change before and after the rotation occurs. 4. The electronic camera according to claim 1, wherein the imaging device moving unit is provided on a first magnetic field generating unit provided on the movable stage side and on the base side. An electronic camera, wherein the movable stage is moved with respect to a base by electromagnetic interaction between the first magnetic field generating means and the second magnetic field generating means. . 5. The electronic camera according to claim 4, wherein said first magnetic field generating means is a conductor coil, and said second magnetic field generating means is a conductive coil.
Wherein the magnetic field generating means is a permanent magnet. 6. The electronic camera according to claim 1, further comprising: a first position detection electrode formed on the movable stage, which detects a position of the solid-state imaging device with respect to the base. A second position detection electrode formed on the base side; and a stage position detection unit. The stage position detection unit detects a change in capacitance between the first and second electrodes. An electronic camera for detecting a position of the solid-state imaging device with respect to the base. 7. The electronic camera according to claim 1, wherein the movable stage is held on the base via an elastic spring. 8. The electronic camera according to claim 7, wherein the elastic spring has a signal line connected to a solid-state imaging device.