JPH03218182A - Photographing device - Google Patents

Abstract

PURPOSE:To obtain an image oscillation correcting device with a simple structure reduced in its size and weight by forming an image pickup element unitedly with a photographing lens body, holding the united body by an elastic member having a high attenuation rate to fix the unitedly body to a video camera body and detecting the oscillation of a lens. CONSTITUTION:The image pickup element 4 is formed unitedly with the lens body 1, the united body is held by the elastic member 3 having a high attenuation rate and fixed to the video camera body, the outline of an object based upon a video signal is detected, and image oscillation is corrected by the horizontal and vertical movement based upon the outline detection. Since the lens 1 and the element 4 are unitedly held by the elastic member 3 having the high attenuation rate, high-frequency and fine image oscillation to be generated at the time of holding the video camera by a hand can be removed, accurate and low-frequency component image oscillation is detected and the image oscillation can be accurately corrected.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a photographing device that can be used in a portable video camera, a video camera integrated with a magnetic recording/reproducing device (VTR), etc. .

[Conventional technology]

Photographic devices have become smaller and lighter, and have become more automated such as automatic focusing, improving their mobility and operability. These features have made it easier to record video. However, when considering the image quality of recorded video, image blur due to camera shake or the like affects the image quality. Particularly in an image shot with a high zoom magnification, if the image is blurred, it becomes difficult to view and the image quality deteriorates, which is not desirable. Although it is possible to obtain image quality with less blur by using a tripod, etc., there is a problem with mobility. Therefore, there is a need for a photographing device that can perform stable camera work with less blur in images without using a tripod or the like.

In order to reduce this image blur (hereinafter referred to as image blur) and obtain stable images, Japanese Patent Laid-Open No. 61-19
Photographing devices such as those shown in Japanese Patent Application Laid-open No. 2178, Japanese Patent Application Laid-open No. 1988-19217, and Japanese Patent Laid-Open No. 192180-1988 have been proposed. This photographing device includes a rotating means capable of rotating the camera body in a yawing direction and a pitching direction with respect to a hand grip, and a detecting means for detecting the amount of shake of the camera body in each of these rotating directions. and a driving means that drives the camera body based on the detection result by this detection means,
It has a control means for correcting camera shake,
When a camera body shake is detected, the camera body is moved in a direction opposite to the direction of the camera body shake by a driving means to correct the camera body shake.

In such a photographing device, since the camera body is moved, the device itself becomes large and heavy.

In view of this point, an imaging device as shown in Japanese Unexamined Patent Publication No. 1-123576 was proposed. This photographic device differs from the previous example in that it has a holding means that holds the photographic lens and image sensor as one body, and that this is configured to be rotatable in the yawing and pitching directions with respect to the camera body. The other configurations are almost the same.

Further, the state in which image blur occurs differs depending on the shooting conditions.

That is, there is a difference between when taking a still picture while holding the video camera and when taking a picture while walking or riding a vehicle while receiving vibrations.

In hand-held still photography, there are many high-frequency components with a small amount of vibration, but in photography while being subjected to vibration, there are many low-frequency components with a large amount of vibration. Therefore, in order to correct small to large fluctuations from a low frequency range to a high frequency range, the correction device becomes large.

[Problems to be Solved by the Invention] As described above, in such a conventional mechanism configuration, a mechanism that holds the lens rotatably in the pitching direction is provided,
This mechanism must be held rotatably in the yawing direction. Therefore, it becomes a large mechanism for use in a portable video camera. Further, the drive mechanism for driving the above-mentioned mechanism also needs to be attached to the holding mechanism, making it difficult to use it in a small, lightweight video camera having a high-performance image stabilization function. It is also necessary to have a wide range of image blur correction.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention has a structure in which the lens body and the photographing element are integrated and held by an elastic member with a high attenuation ratio, and the lens body and the photographing element are held together by an elastic member with a high attenuation ratio, and the lens body and the photographing element are held together in a structure that is attached to the video camera body. At the same time, the camera is configured to detect the outline of the subject based on the video signal, and to correct image blur by horizontal and vertical movement based on the detected outline.

[Function] The present invention reduces and eliminates image blur by having the above-described configuration. In other words, by holding the lens and image sensor together with an elastic member with a high damping ratio, the vibration components of the video camera, which have a high frequency and a small amount of vibration that occur when the video camera is held hand-held, are absorbed by the lens. Try not to let it get across. After doing this, the outline of the subject is detected by the imaging element, and image blur in low frequency components with large vibrations is removed. At this time, since there is no high fine image blur in contour detection, image blur in low frequency components can be detected with high accuracy and image blur correction can be performed.

[Embodiment] A photographing device according to an embodiment of the present invention will be described with reference to FIG. 1 of the drawings.

FIG. 1 is a schematic diagram showing a system configuration for preventing image blur. Reference numeral 1 denotes a photographic lens for photographing a subject, 2 an elastic member with a large attenuation ratio to support the photographic lens, and 3 a photographic lens that is inserted through the elastic member. A holding member 4 is attached to the set body, and 4 is an image pickup element unit attached to the photographic lens. Reference numeral 5 denotes a video signal processing circuit that converts the subject image information formed by the photographing lens onto the image sensor section into an electrical signal. 6 is an edge detection circuit that detects edges of the subject image from a video signal processing circuit; 7 is a memory that stores the edge detection output results; 8 is an image blur amount detection circuit based on the output of the edge detection circuit and the output from the memory. do. A motion vector detection circuit 9 is a readout position control circuit for changing the readout position of the video signal and reading it out based on the output result from the motion vector detection circuit.

The operation of the present invention configured as described above will be explained below.

Suppose that the entire video camera is currently shaking due to hand-held shooting. At this time, the holding member 3 fixed to the video camera also shakes and moves in the same way as the video camera. However, since the photographing lens is held by the holding member 3 via an elastic member with a high attenuation ratio, it does not shake like the holding member 3 does. That is, the vibration is absorbed or blocked by the elastic member having a high damping ratio, and the transmission of the vibration to the photographing lens 1 is reduced or eliminated. An elastic member with a high damping ratio is effective for vibrations with high vibration frequencies and small vibration amplitudes, and removes vibrations with high frequencies and small vibration amplitudes, but for vibrations with low vibration frequencies and large vibration amplitudes. The present invention has a configuration in which the above-mentioned video signal is used to correct blurring for low frequency and large blurring amplitudes. Below is the second part about its operation.
This will be explained using figures.

FIG. 2(a) shows the state of the subject image on the photographing element before and after image blur. FIG. 2(b) shows the output state of the object edge detection circuit in the vertical direction in this state. The solid line indicates before image blur, and the dotted line indicates after image blur. Therefore, by memorizing the output of the edge detection circuit before image blurring and comparing this memorized output with the edge detection output after image blurring, the image movement due to image blurring (Q shown in FIG. 2(b)) can be detected. I understand. By changing the video signal processing position where the video signal of the subject image is read and processed from the image sensor by an amount corresponding to this movement, a video without image blur can be obtained. FIG. 3 shows the relationship between the image sensor and the image readout state.

10 is an imaging range of the image sensor, 11 is a readout area before image blurring, and 12 is a readout area after image blurring. In this manner, the video signal readout area is made smaller than the photographing range of the photographic lens, so that image blur can be corrected. If image blur is detected and corrected by edge detection in this manner, it is detected and corrected for each field of the TV signal, and therefore is not effective against high image blur of 15 Hz or higher. Therefore, in the present invention, in order to remove image blur components having frequencies higher than around 15 Hz, the photographing lens is held by the above-mentioned elastic member having a high attenuation ratio. FIG. 4 shows a sectional view of a main part of a holding example.

15 is the outermost lens barrel of the photographic lens, and 16 is a protrusion provided on the entire lens barrel, which has a screw 6. 17. 18 is an i-character member with a decay ratio. 20 is a tightening screw.

The elastic member 17 is provided with a fitting portion that fits into the protrusion portion and a fitting portion for a tightening screw. The holding member 3 is provided with a hole into which the elastic member 17 is positioned and inserted.

With the above configuration, the photographing lens is held by the holding member. That is, since the photographic lens is held via an elastic member, the set vibration when the camera is held in hand is attenuated or eliminated by vibration absorption by the elastic member. Therefore, vibrations are not transmitted to the photographic lens.

In addition, by arranging the elastic members to support the center of gravity of the photographic lens in a well-balanced manner, the occurrence of vibration due to unbalance is suppressed.The natural frequency of the elastic member is determined by the number and shape of the elastic member that supports the weight of the photographic lens. Than,
Set the frequency to 10Hz or less. By setting in this way, vibrations can be effectively damped and eliminated for frequencies of 10 Hz or more. In FIG. 4, the elastic member is divided into two parts, but the effect is the same even if they are integrated. FIG. 5 shows another holding example. 21. 22 is a fixture attached to the elastic member.

The fixture 21 is adapted to be fastened to a threaded portion of the lens barrel. The fixture 22 has a fastening portion for the screw 20 to attach the holding member.

In both FIGS. 4 and 5, the photographic lens is held by a holding member via an elastic member so as to block vibrations.

A schematic diagram of another embodiment is shown in FIG. First, the configuration of this embodiment will be described. 1 is a photographic lens, 2 is an elastic member, 3 is a holding member, 20 is a screw, 23 is a zoom position detection member that detects the zoom position of the photographic lens, and 24 is a zoom position detected by the output from the zoom position detection member. A zoom position detection circuit, 25 is a shake detector that detects the amount of shake of the photographic lens, 26 is a shake detection circuit that processes the output of the shake detector, and 27 is an output of the zoom position detection circuit and an output of the shake detection circuit. Controlling the readout position of the video signal of the output signal from the video signal processing circuit of the image sensor;
This is a read position control circuit.

FIG. i shows a schematic diagram of the configuration of the zoom detection section.

28 is a variator lens group that changes the zoom magnification, 29 is a variator frame that holds the variator lens group, and 30 is a compensator lens that corrects distortion caused by zooming. 31 is a compensator frame that holds a compensator lens; 32 is a variator frame; 33 is a cam follower mounted on the compensator; and 33 is a cam can with a cam groove for zooming, in which the cam follower fits and slides. , 34 is a zoom can that rotatably supports the cam can, 35 is a zoom can that rotates around the cam can, and 35 has a piece 36 that fits into the notch of the cam can.
37 is a gear provided on the zoom can, 38 is a detection gear that meshes with the gear of the zoom can, 23 is a zoom position detection member having the detection gear attached to a rotating shaft, and 39 is a mounting member.

Next, the operation will be explained. When you rotate the zoom ring,
The cam can rotates as a unit, and the cam follower, which is fitted into the cam groove of the cam can, moves in the direction of the optical axis due to the cam groove.The movement of the cam follower also moves the variator frame and the convencator frame, achieving a zoom operation. Therefore, the rotational position of the zoom can corresponds to the zoom position. The rotational position of the zoom can is detected by a zoom position detection member composed of a detection gear meshing with the zoom can, a potentiometer, or the like. The output from this detection member is subjected to processing such as voltage conversion in a zoom position detection circuit.

This output is input to the read position control circuit.

On the other hand, the output from a blur detector composed of an angular velocity detector and the like is input to a blur detection circuit, subjected to processing such as voltage conversion, and then input to a read position control circuit. In the readout position control circuit, the amount of camera lens shake due to the zoom position corresponds to the amount of image shake on the image sensor of the imaging lens. Arithmetic processing is performed so that the value is obtained, a video shake amount correction value is calculated, and the readout position of the video signal is controlled. The method for calculating the image shake amount correction value is to read out a design value of the image shake amount corresponding to the shake amount of the imaging lens at each zoom position from a stored memory value. Image shake is corrected based on this memory value.

〔Effect of the invention〕

The present invention integrates a photographic lens body and an image sensor, has a structure in which they are held by an elastic member with a high attenuation ratio, and is attached to a video camera body. By detecting the movement of the photographic lens caused by the camera, the movement of the subject image is detected, the reading position of the video signal is controlled, and the image blur is corrected. Therefore, it is possible to obtain an image blur correction device that has a simple structure, is small in size, and is lightweight. Therefore, it is a small device such as a video camera. Can be made lighter.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an image blur correction device showing a positional embodiment of the present invention, FIG. 2 is an explanatory diagram for explaining edge detection, and FIG. 3 is a state of image blur on the image sensor surface. FIG. 4 is a cross-sectional view of a main part showing an example of holding a photographic lens by an elastic member, and FIG. Elastic member 3... Holding member 4... Image sensor section 5...
-Video signal processing circuit 6...edge detection circuit 7...memory 8...movement vector detection circuit 9...readout position control circuit 15...lens barrel 17, 18...elastic member 23... -Zoom position detection member 24...zoom position detection circuit 25...shake detector 26...shake detection circuit 3
5...Zoom can 37...Zoom gear 38.
...Detection gear Fig. 2 Fig. 4 Fig. 1G Fig. 5

Claims (1)

[Scope of Claims] 1. A photographing lens (1) composed of a plurality of lenses for photographing a subject and obtaining a photographed image; an image sensor section (4) for converting the photographed image into an electrical signal; In a photographing device having a video signal processing means (circuit) (5) that generates an image signal from a signal, the mounting structure of the photographing lens (1) to the photographing device is replaced by elastic members (2, 17, 18) with a high attenuation ratio. and the holding member (3
), the photographing lens (1) is attached via an elastic member, and means (6, 7, 8) for detecting image blur based on a video signal; ) A means for correcting image blur (8); 2. The image blur detection means is zoom position detection means (23, 24) of the photographic lens (1).
and a camera shake amount detection means (25, 26) for the photographic lens (1).
The amount of image blur is detected by the detection means, and the image blur correction means (2)
7); The photographing device according to claim 1, comprising: