JP2002171446A - Image pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a video camera that can realize a pixel shift function able to enhance the resolution through a simple, highly reliable and compact configuration. SOLUTION: The image pickup device is provided with a rotatory prism means (plastic prism) 1d that has a refraction function that refracts an incident ray by a prescribed angle θ1 and emits the refracted ray and is configured turnably around an optical axis 1e. The rotatory prism means 1d is turned alternately in both directions by a prescribed angle while being synchronized with reading of a CCD 1b to shift an optical image on the CCD 1b in parallel with an image pickup plane thereby shifting pixels of the image.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup apparatus such as a video camera, a video camera with an electronic still function, and an electronic still camera, and more particularly to an image pickup apparatus having a pixel shifting function for improving the resolution of an image pickup device. is there.

[0002]

2. Description of the Related Art In an image pickup apparatus such as a video camera, a method called pixel shift (hereinafter, also referred to as pixel shift or image shift) is conventionally used as a method for improving the resolution of a captured image. The outline of the above-described pixel shift method is as follows. The relative position of the optical image formed on the photoelectric conversion surface (imaging surface) of the imaging device and converted into an imaging signal with respect to the imaging device is set to a small amount in a direction parallel to the imaging surface. By alternately moving and photographing at each moving position, by combining the obtained plural photographing signals and complementing the pixels, the resolution is improved more than the value restricted by the number of pixels of the image sensor. This is to obtain a high quality image. Hereinafter, a configuration for realizing the pixel shift in the imaging apparatus according to the related art will be specifically described.

FIG. 10 shows a known document, Japanese Patent Application Laid-Open No. Sho 60-5.
FIG. 1 is a configuration diagram of a main part of a solid-state imaging camera according to the related art described in Japanese Patent No. 4576. In FIG. 10, 10
a is a CCD (Charge Cou) which is a solid-state imaging device.
Pled Device), 10b is a parallel flat glass plate, 10c is a thin flexible metal plate fixed to both ends of the glass plate 10b, 10d is a piezoelectric plate which has the metal plate 10c fixed and vibrates according to the application of a voltage. The element 10e is an imaging lens, and 10h is an optical axis of the imaging lens 10e.

The operation of the solid-state imaging camera shown in FIG. 10 when performing a pixel shift will be described. First, the alternating voltage is applied at a predetermined frequency to the piezoelectric element 10d having the property of expanding or contracting according to the positive or negative direction of the applied voltage, thereby repeating the expansion and contraction at the above frequency. Cause vibration. The vibration of the piezoelectric element 10d is transmitted to the glass plate 10b via the metal plate 10c. As a result, the glass plate 10b makes a rotational movement reciprocating in the direction indicated by 10f in FIG. Is repeated at a predetermined frequency equal to Although the glass plate 10b does not have a mechanical rotation axis as a component,
The reciprocating rotation described above is performed using a straight line passing through a point 10g substantially coincident with the center of gravity of b and perpendicular to the paper surface as a rotation axis. The rotation axis is perpendicular to the optical axis 10h.

Since the glass plate 10b is a parallel plate-shaped light transmitting member having parallel opposing surfaces, light rays incident on one surface thereof are emitted from a position shifted in parallel, though the direction is not changed, and the light is shifted. The amount changes according to the incident angle of the light beam on the glass plate 10b. Therefore, after a light beam is incident from the imaging lens 10e on the glass plate 10b performing the reciprocating rotation, the CCD 10
Assuming that an optical image is formed on the photoelectric conversion surface a, the optical image alternately reciprocates in the direction perpendicular to the optical axis at the frequency of the AC voltage. Note that the amount of movement of the optical image in the direction perpendicular to the optical axis is represented by δ in FIG.

Therefore, by appropriately setting the generation timing of the imaging signal based on the photoelectric conversion signal of the CCD 10a and the AC voltage frequency and the phase, a series of imagings in which the images are mutually shifted by δ between the fields are performed. Since a signal is generated, a series of image pickup signals are synthesized to obtain a high-quality image with improved resolution based on the above-described pixel shift method.

[0007] The pixel shift method is disclosed in Japanese Patent Laid-Open No.
There are various proposals other than the technology described in JP-A-54576, for example, JP-A-63-284980, JP-A-5-276452, and JP-A-2000-244826.
The disclosure is also made in Japanese Patent Publication No. However, any of the above disclosed technologies has a configuration in which the optical image performs a reciprocating motion of a predetermined amount by rotating the flat transparent member about a rotation axis perpendicular to the optical axis. This is the same as the conventional solid-state imaging camera shown in FIG.

[0008]

The above-described imaging apparatus which improves the resolution by the pixel shift method according to the prior art has the following problems to be solved. (1) It is necessary to provide a rotation space for the flat transparent member, and the configuration becomes large. As described with reference to FIG. 10, in order to move the optical image by the pixel shift method, the flat light transmitting member (the glass plate 10b in FIG. 10) reciprocates around a straight line perpendicular to the optical axis 10h as a rotation axis. It is necessary to perform a rotation motion, and it is necessary to secure a space for rotation before and after the plate-shaped light transmitting member in the optical axis direction. For home video cameras and electronic still cameras, the size and weight of the device are required to be reduced, and the space between the image pickup device and the image pickup lens is extremely limited. Was difficult to secure. If an attempt is made to secure that space, the size of the imaging lens and the entire camera is inevitably increased, and the commercial value of a video camera or the like may be greatly impaired. (2) The configuration is critical. The configuration shown in FIG. 10 has a suspension structure in which a glass plate 10b is suspended in the air by a piezoelectric element 10d with a flexible metal plate 10c interposed therebetween, and the glass plate 10b is reciprocated by the procedure described above. In order to correctly perform the dynamic motion, the frequency and vibration amplitude of the piezoelectric element 10d, the elastic modulus of the metal plate 10c, the glass plate 10
The design must take into account many parameters such as the mass of b, which is difficult to design and requires a complicated configuration to achieve the desired movement. Is slightly changed, the glass plate 10b may not perform a correct reciprocating rotation. That is, in the prior art, since the configuration is critical as described above, there is a problem that performance and quality are not stable and handling is difficult. (3) A point where an impact or vibration applied from outside affects the image. Similarly, as shown in FIG. 10, the glass plate 10b having a constant inertial mass is suspended in the air by the flexible metal plate 10c, so that when vibration or impact is applied from the outside, the glass plate 10b is accordingly Mutated from the predetermined position,
As a result, there is a possibility that the position of the optical image on the CCD 10a is also changed and the image on the photographing screen moves (also referred to as "image skipping phenomenon"). In an attempt to improve the above-described image skipping phenomenon, the configuration shown in FIG.
Even if a mechanical rotating shaft was newly installed at the position of g, there was no substantial improvement. That is, although the glass plate 10b is fixed to two axes among the three degrees of freedom as a new rotation axis is formed, a predetermined inertial mass is configured to be freely movable in the rotation direction about the rotation axis. Therefore, the glass plate 10b is easily rotated from the regular position by an external impact, and as a result, the above-described image skipping phenomenon may still occur.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and is particularly provided on an image pickup surface side of an image pickup device and is provided with a first time point for an optical image read at a first time point. The optical image to be read is rotated about the optical axis as a rotation center so that the optical image to be read is moved by a predetermined amount in parallel with the imaging surface at a second point in time after a predetermined time has elapsed, and the rotation cycle is synchronized with the reading cycle of the image sensor. By providing a refraction unit that refracts and emits the light emitted from the imaging lens to the imaging device side, a configuration that performs pixel shift for improving resolution is configured compactly and simply, and high reliability is ensured. It is another object of the present invention to provide an imaging device that does not affect an image even when an external impact is applied.

[0010]

In order to solve the above-mentioned problems, the present invention provides an imaging device having the following constitutions (1) to (4). (1) An image pickup apparatus (video camera, video camera with electronic still function, electronic still camera) that obtains a high-quality (12.8 million pixels) captured moving image by using a pixel shifting method, comprising: an image pickup lens 1a; An imaging device (CCD) 1 that reads an optical image captured by the imaging lens 1a at a predetermined cycle and sequentially outputs captured images (screens A and B) 6a and 6b.
b, and an optical image provided on the imaging surface side of the imaging device 1b and read at a second time after a predetermined time has elapsed from the first time with respect to the optical image read at the first time. Is rotated about the optical axis 1e as a rotation center so as to move by a predetermined amount (2.44 μm) in parallel with the optical axis, and the rotation cycle is synchronized with the reading cycle of the image sensor 1b. Refraction means (plastic prism 1d, prism, composite prisms 7a, 8a) for refracting and emitting the emitted light to the image pickup device 1b side, and photographed images 6a, 6b sequentially output by the image pickup device 1b are converted into the image pickup device 1b.
An image synthesizing means for synthesizing in synchronism with a read cycle of the image to generate the high-quality photographed moving image. (2) An imaging apparatus for obtaining a high-quality photographed moving image by using a pixel shifting method, wherein an imaging lens 1a and an optical image captured by the imaging lens 1a are read at a predetermined cycle to obtain captured images 6a and 6b. And an optical image which is provided on the imaging surface side of the image sensor 1b and sequentially reads the optical image at a second time after a lapse of a predetermined time from the first time. The optical image is rotated about the optical axis 1e as a rotation center so that the optical image moves by a predetermined amount in parallel with the imaging surface, and the rotation cycle is synchronized with the reading cycle of the imaging element 1b. Shift means (plastic parallel plate) 9a for shifting outgoing light of the image sensor in parallel and emitting the light toward the image sensor 1b;
The captured images 6a and 6b sequentially output by the
an image synthesizing means for synthesizing in synchronism with a reading cycle of b to generate the high-quality photographed moving image. (3) An imaging apparatus for obtaining a high-quality captured still image by using a pixel shifting method, which sequentially reads an imaging lens and an optical image captured by the imaging lens at a predetermined timing and sequentially outputs the captured image. An image sensor, and an optical image provided on an imaging surface side of the image sensor and read at a second time after a predetermined time has elapsed from the first time with respect to the optical image read at the first time. A revolving unit that rotates about the optical axis as a rotation center so as to move a predetermined amount in parallel with the refraction unit and refracts and emits light emitted from the imaging lens to the imaging device side, and captures an image sequentially output by the imaging device. An image synthesizing unit for generating the photographed still image with high image quality. (4) An imaging apparatus for obtaining a high-quality captured still image by using a pixel shifting method, sequentially reading an imaging lens and an optical image captured by the imaging lens at a predetermined timing, and sequentially outputting the captured image. An image sensor, and an optical image provided on an imaging surface side of the image sensor and read at a second time after a predetermined time has elapsed from the first time with respect to the optical image read at the first time. A shift means for rotating the optical axis about a rotation center so as to move a predetermined amount in parallel with the optical axis, shifting the light emitted from the imaging lens in parallel and emitting the light toward the image sensor, and sequentially outputting the image sensor. An image pickup apparatus, comprising: image synthesizing means for synthesizing a photographed image to generate the high-quality photographed still image.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to FIGS.
FIG. 1 is a block diagram mainly showing an optical system of a video camera according to a first embodiment of the present invention, FIG. 2 is a perspective view of a plastic prism provided in the video camera of FIG. 1, and FIG.
FIG. 4 is a ray diagram of the plastic prism in FIG. 2, FIG. 4 is a plan view illustrating movement of an optical image by refraction and rotation of the plastic prism in FIG. 2, and FIG. 5 is a plan view illustrating FIG. 4 further using vectors. 6 is a schematic diagram for explaining image synthesis performed by the video camera of FIG. 1 by pixel shift, FIG. 7 is a schematic diagram of a composite prism used by the video camera of the second example according to the embodiment of the present invention, and FIG. FIG. 9 is a schematic view of a composite prism used by a video camera of a third example of the embodiment of the present invention. FIG. 9 is a configuration diagram centering on an optical system of the video camera of the fourth example of the embodiment of the present invention. is there.

First, the first embodiment will be described. The video camera according to the present embodiment performs an operation of generating a high-quality captured moving image by performing pixel shift (pixel shift) using a configuration characteristic of the following embodiment, and a high-quality captured still image. Are respectively performed. In the following description, description will be made focusing on generation of a high-quality photographed moving image, and a difference in generation of a high-quality photographed still image will be appropriately supplemented.

In FIG. 1, which is a block diagram mainly showing the optical system of the video camera of this embodiment, the video camera is provided with an imaging lens 1a for photographing a subject 1c and a CCD 1b for outputting an imaging signal by photoelectric conversion. It is the same as the conventional one.

Further, as a characteristic feature of the video camera of this embodiment, a plastic prism 1d having a surface perpendicular to the optical axis 1e and a surface facing the surface with a small angle of inclination with respect to the surface is provided. A prism fixing frame 1f for fixing and holding the plastic prism 1d therein, a prism frame rotation guide 1g for rotatably holding the prism fixing frame 1f therein, and a prism holding the prism frame rotation guide 1g therein. A prism rotation driving device 1h for rotating the plastic prism 1d integrated with the fixed frame 1f about the optical axis 1e as a rotation axis, and a control microcomputer 1i for controlling the rotation driving operation of the prism rotation driving device 1h are provided.

Incidentally, the plastic prism 1d shown in FIG.
In the actual configuration, the above inclination angle is a small angle,
In FIG. 1, the inclination angle is emphasized for clarity of the description. This applies to other drawings of the present application. Although the lens 1a in FIG. 1 is schematically illustrated as one block, it is actually configured as a lens group including a plurality of lenses. Further, the plastic prism 1d described above is different from the lens 1a in FIG.
Although arranged between the CD 1b and the CD 1b, a different configuration may be adopted so as to be arranged between any of a plurality of lenses included in the lens 1a.

As shown in the perspective view of FIG. 2, the plastic prism 1d has a first surface 1d1, which is a plane perpendicular to the optical axis 1e, and a small angle with respect to the first surface 1d1. Second surface 1 which is a flat surface facing with inclination
d2, a prism means made of a plastic material having optical transparency.

FIG. 3 shows that the plastic prism 1d is divided into a normal 1d3 and a normal 1d3 of the second surface 1d2.
A straight line 1 passing through the intersection of the first surface and the second surface and parallel to the optical axis 1e
It is the figure cut | disconnected by the plane containing d4. The refraction of light rays performed by the plastic prism 1d will be described with reference to FIG. In FIG. 3, a light beam traveling on a straight line 1d4 parallel to the optical axis 1e from the left to the right in the drawing enters the first surface 1d1 of the plastic prism 1d, and is refracted at a predetermined angle by its refraction. From the second surface 1d2.

The above-mentioned refraction angle, which is the angle between the incident light beam and the outgoing light beam, is θ ₁ , and the angle (hereinafter, prism angle) between the normal 1d3 of the second surface 1d2 and the straight line 1d4 parallel to the optical axis 1e described above. ) Is i, and the refractive index of the light transmissive material constituting the plastic prism 1d is N, and when i is sufficiently small, the following equation is satisfied. θ ₁ = (N−1) i (Equation 1)

Next, the operation of shifting the optical image due to the rotation of the plastic prism 1d will be described. FIG. 4 is a schematic diagram for explaining a shift operation of an optical image as viewed on a plane perpendicular to the optical axis 1e.
d performs a rotational movement about the optical axis 1e.
Further, the second surface 1 of the plastic prism 1d described above.
The inclination direction of d2, that is, the direction in which the normal line 1d3 of the second surface 1d2 is inclined is referred to as "prism direction". The prism direction at a certain rotational position is A, and the prism direction at a further rotation by a predetermined angle therefrom. B, and the direction in which A and B are bisected is referred to as the rotation center direction and is shown in FIG.

The shift direction of the optical image that shifts (moves) by rotating the plastic prism 1d from the state of the prism direction A shown in FIG. 4 to the state of the prism direction B with respect to the rotation center direction described above. The vertical orientation is geometrically obvious.

The shift amount of the optical image is an amount obtained by vector calculation as follows. That is, FIG.
And 5 is a plan view on a plane perpendicular to the optical axis 1e similarly, _vector S ₁ the movement vector optical image is moved by the refracting action described with reference to FIG 3 above in the state of the prism direction A, Similarly, in the state of the prism direction B, the movement vector by which the optical image moves
_{Assuming that vector} S ₂ , the movement vector _{vect of the} optical image accompanying the rotation of the plastic prism 1 d described with reference to FIG.
_or S is given by _vector S = _vector S _{2 −vector} S ₁ (Equation 2). Note that the subscript " _vector " indicates a vector quantity. By obtaining the magnitude of │ _vector S│ motion vector _vector S obtained in the above (Formula 2) by calculating the shift amount of the optical image caused by the rotation of the plastic prism 1d is obtained. Needless to say, the direction of the movement vector _vector S is orthogonal to the rotation center direction as described above.

The plastic prism 1d described above
Utilizing the shift action of the optical image due to refraction and rotation of
A pixel shift operation performed by the video camera according to the present embodiment will be described. In performing the pixel shift, first, an operation of selecting a pixel shift mode of the video camera is performed.
Next, the control microcomputer 1i controls the prism rotation driving device 1h so that the plastic prism 1d is rotated with the optical axis 1e as a rotation axis, and the prism directions A and B are alternately realized.

When the plastic prism 1d is rotated, the plastic prism 1d may be configured to perform a reciprocating rotation motion in which the rotation direction repeats reversing so as to reciprocate between the prism direction A and the prism direction B, or the plastic prism 1d may be rotated. The prism 1d may be rotated at a constant speed in a constant direction so that the states in the prism directions A and B alternately appear in a predetermined cycle. In any case, the state in the prism direction A and the state in the prism direction B
The control microcomputer 1i controls the prism rotation driving device 1h so as to appear in synchronization with the read timing of b.

In the state where the above-mentioned rotational driving is performed, the first image is taken in the direction of the prism A (referred to as photographing A), and the second image is taken in the direction of the prism B (photographing B). By repeating this alternately, a series of images in which images (images A and B) in which the images are shifted by a predetermined amount from each other alternately are obtained.

A new high-resolution composite image is generated by synthesizing adjacent captured images A and B in the obtained series of images, and a series of high-resolution composite images is obtained. A moving image as an image is obtained.

By the way, a high quality photographed still image, which is another method of the pixel shift operation performed by the video camera of this embodiment using the above-described shift operation of the optical image due to the refraction and rotation of the plastic prism 1d. A method for generating the will be described.

When performing a pixel shift, first, an operation of selecting a pixel shift mode of the video camera is performed. Next, the control microcomputer 1i controls the prism rotation driving device 1h so that the plastic prism 1d is rotated about the optical axis 1e as the rotation axis, and the prism direction A and the prism direction B are realized.

The control microcomputer 1i controls the prism rotation driving device 1h so that the state in the prism direction A and the state in the prism direction B appear in synchronization with the readout timing of the CCD 1b.

In the prism direction A, the first image is taken (referred to as photographing A), and in the prism direction B, the second image is taken (referred to as photographing B). Images (captured images A and B) are obtained.

By combining the obtained photographed image A and photographed image B, a photographed still image which is a new high-resolution composite image is obtained.

The description will be continued by returning to the method for obtaining the photographed moving image again. Image synthesis for generating a high-quality captured moving image can be realized by a method and configuration used in a conventional pixel shift method, which is a known technique.

FIG. 6 shows an example of an image synthesizing method, in which the pixel pitch is 3.45 μm and the number of pixels is 320.
A captured image A (screen A) 6a and a captured image B each having 10,000 pixels
(Screen B) 6b is captured based on the above-described pixel shift method. At this time, the shift amount of the optical image due to the rotation of the plastic prism 1d is 2.44 μm, and the shift direction is the diagonal direction of the screen. Screen A obtained
By linking (6a) and screen B (6b), an intermediate image 6c having a file size of 12.8 million pixels is obtained.

Further, new pixel data (C) is generated from the adjacent pixels of the screen A and the pixels of the screen B in the intermediate image 6c by the complementation method to obtain 128 pixels.
A final composite image 6d consisting of 100,000 pixels is obtained.

A specific configuration example of the plastic prism 1d used in the video camera of the present embodiment described above is shown.
The plastic prism 1d required to shift the optical image by 2.44 μm described with reference to FIG. 6 has, for example, the following configuration. Prism angle i: 0.098 degrees Refractive index N of the prism: 1.49 Optical distance between the prism and the photoelectric conversion surface of the CCD: 8.
4 mm Rotation angle of prism required to shift optical image: 20
Every time

According to the video camera of the present embodiment described above, since the plastic prism 1d is rotated about the optical axis 1e, the pixel shift for moving the optical image in parallel to the imaging surface is realized. The configuration for pixel shift can be arranged in a small space, and there is no need to provide an escape space for reversing the reciprocating rotation of the glass plate unlike the configuration of the related art, and the video camera is small. Can be realized.

Further, according to the video camera of the present embodiment, the plastic prism 1d, which is a main component for performing pixel shift, rotates around the optical axis 1e (rotational movement in a certain direction, or rotation within a predetermined range). (Rotational motion), it is possible to realize a video camera which has a simple configuration, is not critical unlike the conventional suspension structure, is easy to design, and has high reliability.

Further, according to the video camera of the present embodiment, the plastic prism 1d is similarly configured to be rotatable about the optical axis 1e. Since the change is small, the plastic prism 1 due to external impact or the like is applied.
The displacement of d is very small, and the image skipping phenomenon due to the impact can be prevented.

Next, a second embodiment will be described. The video camera of this embodiment differs from the first embodiment in the configuration of the plastic prism 1d. That is, as shown in FIG. 7, the plastic prism 1 of the first embodiment
In contrast to d consisting of a single prism, the present embodiment has a configuration including a composite prism 7a in which a first prism 7a1 and a second prism 7a2 are adhered and fixed on an attaching surface.

Since the plastic prism 1d in the first embodiment has a single structure, the prism angle (inclination angle) must be realized at a small angle of, for example, 0.098 degrees, which is the numerical example described above. In this case, strict control is required. However, since the present embodiment is configured by the composite prism 7a, by appropriately selecting the inclination angle and the refractive index of each of the constituent prisms, a larger prism angle and a larger prism angle are provided so as to facilitate production. , It is possible to realize a configuration having a larger allowable tolerance range.

Next, a third embodiment will be described. As shown in FIG. 8, the video camera of this embodiment uses a composite prism 8a instead of the single-piece plastic prism 1d used in the first embodiment. However, the composite prism 8a of the present embodiment is different from the composite prism 7a of the second embodiment, and the first prism 8a1 constituting the composite prism 8a.
And the second prism 8a2 have a point-symmetrical shape in the optical axis direction, and only the first prism 8a1 rotates in synchronization with the reading of the CCD, and the second prism 8a2 is fixedly disposed. .

With the above configuration, the first prism 8a
Light rays passing through the first and second prisms 8a2 cancel each other out of chromatic aberration generated at the time of refraction, and as a result, an optical image with little chromatic aberration is obtained. Therefore, the composite prism 8a of the present embodiment can have a larger prism angle than the plastic prism 1d of the first embodiment in which the prism angle is set to a small angle in consideration of chromatic aberration. As a result, the production of the composite prism 8a is easier, and the rotation angle can be reduced, so that high-speed rotation and downsizing of the video camera can be realized.

Next, a fourth embodiment will be described with reference to FIG.

The video camera of this embodiment has a lens 1a,
The provision of the CCD 1b, the prism rotation driving device 1h, and the control microcomputer 1i is the same as that of the first embodiment described above with reference to FIG. 1, except that the plastic prism 1d used in the first embodiment is replaced by a plastic. The parallel plate 9a is used. The plastic parallel plate 9a is a light-transmitting flat plate having opposing surfaces parallel to each other. Light rays incident on the plastic parallel plate 9a at a certain incident angle are shifted in parallel according to the incident angle and emitted.

Further, in the video camera of this embodiment, the parallel plate fixing frame 9b for holding and fixing the plastic parallel plate 9a at a predetermined angle with respect to the optical axis 1e and the plastic parallel plate 9a is tilted at the predetermined angle. And a parallel plate frame rotation guide 9c for holding the parallel plate fixed frame 9b integral with the frame rotatable around the optical axis while maintaining the state.

With the above configuration, the control microcomputer 1i
The pixel shift is realized by rotating the plastic parallel plate 9a by a predetermined angle in synchronization with the reading of the CCD 1b by the prism rotation driving device 1h in accordance with the control described in the first embodiment. The plastic parallel plate 9a whose parallel surfaces face each other is characterized in that it is easier to produce than the plastic prism 1d having a small angled inclined surface.

Next, a fifth embodiment will be described.

The video camera of this embodiment has a configuration similar to any one of the first to fourth embodiments described above, but the control microcomputer 1i performs the following characteristic control. . That is, the control microcomputer 1i in the present embodiment has a function of variably controlling the direction and / or amount of pixel shift.

The shift amount of the pixel shift is controlled by changing the rotation angle of the straight line of the plastic prism 1d or the like facing the prism direction. The shift direction of the pixel shift is controlled by changing the rotation center direction described above.

With the above configuration, the same configuration can cope with a plurality of pixel shifts having different specifications such as a horizontal pixel shift, a vertical pixel shift, and a diagonal (diagonal) pixel shift. It can contribute to the enhancement of the function of the video camera. Furthermore, remarkable effects are exhibited, such as sharing parts between multiple video camera models with different pixel shift specifications, automating the process of adjusting various amounts related to pixel shift, and enabling fine adjustment. Is done.

In each of the embodiments described above, the plastic prism 1d is used in order to clarify the gist of the invention.
Although the plastic parallel plate 9a and the like have been described as exhibiting a characteristic effect of the present invention by performing a rotational movement about the optical axis 1e as a center of rotation, a configuration parallel to the optical axis 1e is different from that. It is also conceivable to configure a straight line as the axis of rotation, which is also encompassed by the present invention. Further, in the video cameras of the second to fifth embodiments described above, not only high-quality captured moving images but also high-quality captured still images using pixel shifting are used, as in the first embodiment described above. Of course, or only one of them may be generated.

[0051]

As described above in detail, the present invention provides a second optical system which is provided on the imaging surface side of an image sensor and which is provided with a predetermined time from the first time with respect to the optical image read at the first time. The optical image to be read at the time is rotated about the optical axis so that the optical image moves by a predetermined amount in parallel with the imaging surface, and the rotation cycle is synchronized with the reading cycle of the image sensor, and the light emitted from the imaging lens is By providing a refraction means for refracting and outputting the image to the image sensor side, a configuration for performing a pixel shift for improving the resolution is compactly and simply configured, and high reliability is ensured. An imaging device that does not affect the image quality can be provided.

[Brief description of the drawings]

FIG. 1 is a configuration diagram centering on an optical system of a video camera according to a first embodiment which is an embodiment according to the present invention.

FIG. 2 is a perspective view of a plastic prism included in the video camera of FIG.

FIG. 3 is a ray diagram in the plastic prism of FIG. 2;

FIG. 4 is a plan view illustrating movement of an optical image due to refraction and rotation of the plastic prism of FIG. 2;

FIG. 5 is a plan view illustrating FIG. 4 further using vectors.

FIG. 6 is a schematic diagram illustrating image synthesis performed by the video camera of FIG. 1 by pixel shift.

FIG. 7 is a schematic diagram of a compound prism used in a video camera of Example 2 according to an embodiment of the present invention.

FIG. 8 is a schematic diagram of a compound prism used in a video camera according to a third example of the embodiment of the present invention.

FIG. 9 is a configuration diagram centering on an optical system of a video camera that is a fourth example of an embodiment of the present invention.

FIG. 10 is a configuration diagram of a solid-state imaging camera according to the related art.

[Explanation of symbols]

 1a Imaging lens 1b CCD (imaging element) 1d Plastic prism (refraction means) 1e Optical axis 6a Photographing screen A (photographed image) 6b Photographing screen B (photographed image) 7a Compound prism (refractive means) 8a Compound prism (refractive means) 9a Plastic parallel plate (shift means)

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Claims (4)

[Claims] 1. An imaging apparatus for obtaining a high-quality captured moving image by using a pixel shifting technique, comprising: an imaging lens; an optical image captured by the imaging lens being read at a predetermined cycle; and sequentially outputting the captured image. An imaging device provided on the imaging surface side of the imaging device, wherein the optical image read at a first time is read at a second time after a lapse of a predetermined time from the first time. The optical axis is rotated about the optical axis so as to move by a predetermined amount in parallel with the surface, and the rotation cycle is synchronized with the reading cycle of the image sensor, and the light emitted from the image sensor is transmitted to the image sensor side. Refracting means for refracting and emitting light to the imaging element, and image synthesizing means for synthesizing photographed images sequentially output by the imaging element in synchronization with a reading cycle of the imaging element to generate the high-quality imaging moving image. Imaging device characterized by the following Place. 2. An imaging apparatus for obtaining a high-quality captured moving image by using a pixel shifting method, comprising: an imaging lens; an optical image captured by the imaging lens being read at a predetermined cycle; and sequentially outputting the captured image. An imaging device provided on the imaging surface side of the imaging device, wherein the optical image read at a first time is read at a second time after a lapse of a predetermined time from the first time. The optical axis is rotated about the optical axis as a rotation center so as to move by a predetermined amount in parallel with the surface, and the rotation cycle is synchronized with the reading cycle of the image sensor, and shifts outgoing light from the imaging lens in parallel. A shift unit that emits light toward the image sensor side, and an image synthesizing unit that synthesizes a captured image sequentially output by the image sensor in synchronization with a reading cycle of the image sensor to generate the high-quality captured moving image. It is special that An image pickup device. 3. An imaging apparatus for obtaining a high-quality captured still image by using a pixel shifting method, wherein an imaging lens, and an optical image captured by the imaging lens are sequentially read at a predetermined timing, and the captured images are sequentially read. An image sensor to be output, provided on the imaging surface side of the image sensor, and an optical image read at a second time after a lapse of a predetermined time from the first time with respect to the optical image read at a first time. Refraction means for rotating about an optical axis as a rotation center so as to move by a predetermined amount in parallel with an imaging surface, and refracting and outputting refraction light from the imaging lens to the imaging element side; and a captured image sequentially output by the imaging element And an image synthesizing means for synthesizing the image and generating the high-quality photographed still image. 4. An imaging apparatus for obtaining a high-quality captured still image by using a pixel shifting method, wherein an imaging lens and an optical image captured by the imaging lens are sequentially read at a predetermined timing to sequentially capture the captured images. An image sensor to be output, provided on the imaging surface side of the image sensor, and an optical image read at a second time after a lapse of a predetermined time from the first time with respect to the optical image read at a first time. A shift unit that rotates about an optical axis as a rotation center so as to move a predetermined amount in parallel with an imaging surface, shifts light emitted from the imaging lens in parallel, and emits the light to the image sensor side, and the image sensor sequentially includes An image synthesizing device, comprising: image synthesizing means for synthesizing a captured image to be output to generate the high-quality captured still image.