JPH0636575B2 - Imaging device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video camera.

2. Description of the Related Art In recent years, with the spread of video tape recorders (hereinafter referred to as VTRs), there are more opportunities to shoot with a video camera, and it is possible to perform stable camera work with less image blur even without using a tripod. Video camera is required.

Hereinafter, an example of the above-described conventional imaging device will be described with reference to the drawings. Conventionally, a photographing apparatus of this type has a structure as shown in FIGS. 3 and 4, for example, as disclosed in Japanese Patent Laid-Open No. 53-64175. FIG. 3 is a front view of a conventional photographing apparatus, and FIG. 4 is a side view. 3 and 4
In the figure, there is a rotor case 1 having a built-in rotor that rotates at a high speed as a directional gyro, which is supported by a horizontal gimbal 3 on left and right horizontal shafts 2, and the horizontal gimbal 3 is vertically supported by left and right gimbal shafts 4. It is supported by the gimbal 5. Similarly, in the vertical gyro, the center rotor case 6 is supported by the horizontal gimbal 7 and the vertical gimbal 8, and the video camera 9 and the like are installed on the rotor case 6.

Problems to be Solved by the Invention However, in the above-described configuration, since the gyro that rotates at high speed is used, the device becomes large in size and the weight also increases. Therefore, normally, the entire device must be installed and used. In addition to the problem of lack of mobility, when handheld shooting is performed and it is not necessary to prevent image blur, it is sufficient to stop the image blur prevention means such as a gyro. There is a problem in that the horizontal gimbals 3 and 7 and the vertical gimbals 5 and 8 lose their stability, and the video camera becomes unstable, making it difficult to carry.

Means for Solving the Problems In order to solve the above problems, the present invention relates to a photographing lens for photographing a subject, a photoelectric conversion unit for converting an optical image from the photographing lens into an electric signal, a photographing lens and photoelectric conversion. Holding means for integrally holding the means so that the optical axes thereof coincide with each other,
Rotation support means for rotatably supporting the holding means so as to be rotatable in the panning direction or the pitching direction, and locking means for returning the holding means to a predetermined posture and locking it so as not to rotate, and being driven by a motor. And a detection circuit for detecting that the locking device has locked the holding device, and a control circuit for cutting off the power supply to the motor in response to a detection signal from the detection device.

Effect The present invention does not use a large and heavy gyro as in the conventional structure due to the above-described configuration, so that it is easy to construct a small and lightweight gyro and a photographer can use it by hand. Further, by locking the holding means, the photographing axis of the camera body and the optical axis of the photographing lens coincide with each other, so that the photograph can be taken without a sense of discomfort even after locking.

Further, when locking the lens barrel, the power supply to the motor is cut off after confirming the locking operation.

Embodiment Hereinafter, an image pickup apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of the entire imaging device,
FIG. 2 is a sectional view taken along line XX of FIG.

First, the overall configuration of the image capturing apparatus will be described with reference to FIGS. 1 and 2.

In FIGS. 1 and 2, a taking lens 21 for taking an image of a subject and an image pickup device 22 such as a CCD provided on the focal plane of the taking lens are held by a lens barrel 23. Also,
The electric signal converted from the optical image by the image pickup device 22 is converted into a predetermined video signal by the video circuit 24. Lens barrel 23
Ball bearings 25 and 26 are respectively press-fitted into the upper portion 23a and the lower portion 23b of the first frame 27. Rotating shafts 28 and 29 are rotatably fitted to the ball bearings 25 and 26 from above and below the first frame 27, respectively. The cage lens barrel 23 is rotatable with respect to the first frame 27. Further, a ring-shaped magnet 31 which is magnetized as required is fixed to a lower portion 23b of the lens barrel 23 via a back plate 30 made of a magnetic material. A stator winding 33 adhered to a stator flat plate 32 made of a magnetic material is fixed to the first frame 27 so as to face the magnet 31.

Further, in order to detect the rotational position of the lens barrel 23, a hall element 32a is provided on the stator flat plate 32 so as to face the magnet 31. Ball bearings 34 and 35 are press-fitted into the left and right sides of the first frame 27, and rotary shafts 37 and 38 are rotatably fitted to the ball bearings 34 and 35 from the left and right sides of the second frame 36, respectively. The cage lens barrel 23 and the first frame 27 are
It is rotatable with respect to the frame 36. On the right side of the first frame 27, a back plate made of a magnetic material.
A ring-shaped magnet with the required magnetization through 39
40 is fixed. The second facing the magnet 40
A stator winding 42 adhered to a stator flat plate 41 made of a magnetic material is fixed to the frame 36. Further, in order to detect the rotational positions of the first frame 27 and the lens barrel 23 in the tilting direction, the stator flat plate 41 faces the magnet 40.
Is provided with a hall element 41a. An angular velocity sensor 43 for detecting the angular velocity in the panning direction is fixed to the lens barrel 23, and the angular velocity in the tilting direction of the lens barrel 23 and the first frame 27 is detected in the first frame 27. The angular velocity sensor 44 for doing so is fixed. The control circuit 45 so that the output signals of the angular velocity sensors 43 and 44 become zero, the actuator 46 including the magnet 31 and the stator winding 33 that rotate the lens barrel 23 in the panning direction, the lens barrel 23, First frame
An actuator 47 composed of a magnet 40 and a stator winding 42 for rotating the 27 in the tilting direction is drive-controlled.

When locking the lens barrel 23, by turning on the lock switch 50, power is supplied from the control circuit 45 to the motor 52 fixed to the lock base 51, and the motor 52 rotates. The rotational force of the motor 52 is transmitted to the lock gear 56 provided on the lock shaft 55 via a reduction mechanism including idler gears 53 and 54 provided on the lock base 51. Lock shaft
55 is slidably engaged with the support member 57, and the cam groove 57a provided on the support member 57 is engaged with the cam pin 55a provided on the lock shaft 55 to guide the movement of the lock shaft 55. ing.

The end shape of the lock shaft 55 is spherical, and the optical axis of the lens barrel 23 and the photographing axis of the camera body coincide with each other by contacting the conical recess 58 provided in the rear portion of the lens barrel 23. Lock the lens barrel 23 as follows. The conical recess 58 provided in the rear portion of the lens barrel 23 is sized so as to come into contact with the lock shaft 55 in the rotation range of the lens barrel 23.

The motor 52 has a built-in rotation amount detector 60. How many rotations of the motor 52 the lock shaft 55 can reliably lock the lens barrel 23 can be known from the reduction ratio of the reduction mechanism. Therefore, the rotation amount detector 60 has a predetermined rotation amount, that is, the lock shaft 55 is the lens barrel 23. The control circuit 45 cuts off the power supply to the motor 52 when it detects the amount of rotation required to lock the motor.

Regarding the imaging device configured as described above, the first
The operation will be described with reference to FIGS.

When hand-held shooting is performed with a video camera, the video camera shakes due to camera shake or fatigue, which causes shaking of a shot image (so-called image blur). The vibration of the lens barrel 23 caused by this video camera is detected by the angular velocity sensor 43 (panning direction), 44
(Tilting direction), the control circuit 45 supplies electric power to the stator windings 33, 42 of the actuators 46, 47 so that the outputs from the angular velocity sensors 43, 44 become zero. Since the lens barrel 23 does not shake with respect to the absolute coordinates, it is possible to reduce the image blur in the horizontal and vertical directions. For example, if the lens barrel 23 shakes in the tilting direction (the direction of arrow I in FIG. 1), an angular velocity sensor that detects the shake in the tilting direction.
The control circuit 45 supplies electric power to the stator winding 42 of the actuator 47 so that the output of 44 becomes zero to control the drive in the direction opposite to the arrow I direction, whereby the image blur in the tilting direction can be prevented. . Similarly, in the panning direction, image blur can be prevented. When image blurring occurs in the diagonal direction, the angular velocity sensor 43 (panning direction) and the angular velocity sensor 44 (tilting direction) detect the amount of shake (angular velocity), and the angular velocity sensors 43 and 44 in both directions detect Since the control circuit 45 supplies electric power to the stator windings 33 and 32 of the actuators 46 and 47 so that the output becomes zero, it is possible to prevent image blurring in an oblique direction.

When carrying around or turning off the image blur prevention effect,
When the lock switch 50 is turned on, the control circuit 45 supplies electric power to the motor 52 to rotate the motor 52. The rotational force of the motor 52 is transmitted to the lock gear 56 provided on the lock shaft 55 via the reduction gear mechanism including the idler gears 53 and 54, and the cam pin 55a provided on the lock shaft 55 is locked using the cam groove 57a of the support member 57 as a guide. The shaft 55 is moved in the optical axis direction (the direction of arrow H) so that the lock shaft 55 is brought into contact with a conical recess 58 provided in the rear portion of the lens barrel 23 so that the optical axis of the lens barrel 23 and the subject of the camera body are opposed to each other. Lock to match the shooting axis. When the rotation amount detector 60 detects the predetermined rotation amount, the control circuit 45 cuts off the power supply to the actuators 46, 47 and the motor 52.

Also, when turning on the image blur prevention effect, turn off the lock switch 50, and the control circuit 45 first turns the motor.
Supply power to 52 and rotate motor 52. motor
The rotational force of 52 is transmitted to the lock gear 56 provided on the lock shaft 55 through the reduction mechanism including the idler gears 53 and 54, and the cam pin 55a provided on the lock shaft 55 has the cam groove 57a of the support member 57.
Is used as a guide to move the lock shaft 55 in the optical axis direction (the direction opposite to the arrow H) to separate the lock shaft 55 from the conical recess 58 provided in the rear portion of the lens barrel 23, and the lens barrel 23 is removed. Locked. After that, the control circuit 45 is an actuator
Power is supplied to 46 and 47 to prevent image blur.

As described above, according to the present embodiment, since a large and heavy gyro is not used, the whole photographing apparatus is small and lightweight, and handheld photographing can be easily performed.

Also, since the lens barrel can be arbitrarily locked with the operation switch, when the image stabilization is not required, the operation lens can be used to return and lock the shooting lens and the image sensor to a predetermined posture, and can be handled in the same way as a normal shooting device. Since the power supply to the motor was cut off later, the operation is extremely reliable and a small amount of power is required.

In this embodiment, the rotation amount detector 60 is used to detect the lock operation, but the present invention is not limited to this. For example, the lock position of the lock shaft 55 may be detected by a micro switch, a proximity switch, or the like. good. Further, it is obvious that the lock operation can be detected by utilizing the fact that the current of the motor 52 rapidly increases after the lock.

EFFECTS OF THE INVENTION As described above, according to the present invention, since a large and heavy gyro is not used, the overall size of the photographing apparatus is small and light, and handheld photographing can be performed easily.

Furthermore, when camera shake correction is not required, the shooting lens and photoelectric conversion means can be returned to a predetermined posture and locked to handle the camera in the same way as a normal shooting device, and the power supply to the motor can be cut off after locking, thus locking operation. It's extremely reliable and reliable, and it requires less power.

[Brief description of drawings]

FIG. 1 is a block diagram of an image pickup apparatus in an embodiment of the present invention,
FIG. 2 is a sectional view taken along the line XX in FIG. 1, FIG. 3 is a front view of a conventional photographing device, and FIG. 4 is a side view of the conventional photographing device. 21 …… Shooting lens, 22 …… CCD, 23 …… Lens barrel,
45 …… control circuit, 50 …… lock switch, 52 …… motor, 55 …… lock shaft, 58 …… conical recess, 60 …… rotation amount detector.

Claims (1)

[Claims] 1. A photographic lens for photographing a subject, a photoelectric conversion means for converting an optical image from the photographic lens into an electric signal, and the photographic lens and the photoelectric conversion means are integrated so that their optical axes coincide with each other. A holding means for holding the holding means, a rotation supporting means for rotatably supporting the holding means in a panning direction or a pitching direction, and a locking means for returning the holding means to a predetermined posture and preventing the rotation. A lock circuit driven by a motor; a detection circuit that detects that the lock circuit locks the holding circuit; and a control circuit that cuts off power supply to the motor in response to a detection signal from the detection circuit. Shooting device.