JP2001309229A - Solid-state imaging apparatus and resolution conversion apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily enhance resolution of photographic image without making the device costly and losing its compactness. SOLUTION: In an imaging apparatus, there is arranged a pixel shift device such as a prism that shifts the optical axis of incident light or the like in front of a digital steel camera (a solid-state imaging apparatus) having a function to compose a plurality of photographic images photographed by a pixel shift function. With this, a subject is imaged first by an ordinary mode and then by shifting optical axis by the pixel shift device. The resultant two sheets of images are composed to provide an image of high resolution.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state imaging device such as a video camera, a video camera with an electronic still function, and an electronic still camera. The present invention relates to a possible solid-state imaging device and a resolution conversion device that performs pixel shift shooting in front of the solid-state imaging device.

[0002]

2. Description of the Related Art Conventionally, there is a camera of a type in which a conversion device is arranged in front of an imaging device to change an imaging state like a tele-conversion lens, but similarly, a conversion device is arranged in front of an imaging device. There has been no solid-state imaging device such as an electronic still camera capable of achieving higher resolution.

[0003]

Generally, as a method for increasing the resolution of a solid-state image pickup device, there is a pixel shift (hereinafter, referred to as pixel shift) photographing method. The pixel shift function is entirely built into the solid-state imaging device main body. Therefore, even if this function is added to an imaging device having no pixel shift photographing function, or if it is further added to an imaging device having the pixel shift photographing function. There is a problem that the apparatus is expensive due to the modification. In addition, there is also a problem that the apparatus is enlarged due to the remodeling and the compactness at the time of normal photographing is lost.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to make it easy to make the apparatus expensive and not to lose the compactness during normal photographing. An object of the present invention is to provide a solid-state imaging device and a resolution conversion device that can increase the resolution of a captured image.

[0005]

In order to achieve the above object, a feature of the present invention is to provide a solid-state imaging device having a function of synthesizing a plurality of picked-up images taken by a pixel shift function. , And a conversion device having a pixel shift element for shifting the optical axis of light incident on the lens.

Another feature of the present invention is that in the solid-state imaging device, the solid-state imaging device includes a conversion device provided in front of a lens of the solid-state imaging device and having a pixel shift element for shifting an optical axis of light incident on the lens. Is to do.

[0007] Another feature of the present invention is to include means for controlling the pixel shift direction or amount of the pixel shift element.

Another feature of the present invention resides in that there is provided means for tilting the pixel shift element in the conversion device with respect to the optical axis.

Another feature of the present invention is that the pixel shift element, which is substantially perpendicular to the optical axis in the conversion device, is rotated about the optical axis.

Another feature of the present invention is that the conversion device includes a plurality of pixel shift elements.

Another feature of the present invention resides in that there is provided means for inserting and removing the pixel shift element with respect to the conversion device.

Another feature of the present invention is that the pixel shift element is a prism having a small angle.

Another feature of the present invention is that the pixel shift element is a compound prism formed by combining two or more prisms having a small angle.

Another feature of the present invention is that one of the single prisms forming the composite prism is rotated.

Another feature of the present invention is to allow a personal computer or a printer connected externally to perform a process of synthesizing a plurality of images captured by the pixel shift function.

Another feature of the present invention is that a pixel shift element for shifting an optical axis is provided in a housing.

Another feature of the present invention is that the pixel shift element is a composite prism formed by combining two or more prisms having a small angle, and at least one of the single prisms forming the composite prism. Is to rotate.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of a solid-state imaging device according to a first embodiment of the present invention. A pixel shift adapter 2 is disposed in front of a lens 11 of a digital still camera (DSC) 1. The pixel shift adapter 2 has a built-in pixel shift element (a glass or plastic prism or the like) 21 and is detachably disposed in front of the lens 11 described above. 2f is a front view of the pixel shift adapter 2 to which a switching button 22 for manually switching the rotation direction of the prism 21 is attached.

Next, the operation of this embodiment will be described.
After fixing the digital still camera 1, (1) the pixel shift adapter 2 is arranged in front of the lens 11 of the digital still camera 1. (2) The switching button 22 of the pixel shift adapter 2 is switched to set, for example, a normal mode, and (3) shooting A is performed in the normal mode.
(4) The switching button 22 is switched to change the rotation angle direction of the prism 21, and the photographing B is performed in the shift mode.

Here, when the switching button 22 is switched, the prism 21 rotates around the optical axis as shown in FIG. In the normal mode, the direction of the prism 21 is the direction of A, but in the shift mode, it becomes the direction of B. If the shift amount at that time is represented by a vector, as shown in FIG.
= S2-S1. When the prism 21 is rotated around the optical axis in this way, the subject is imaged on the CCD 12 with a shift of, for example, 0.0115 degrees as shown in FIG. The rotation of the prism only needs to be in an in-plane direction perpendicular to the optical axis, and the center of rotation may be other than the optical axis. For example, when the rotation angle is small, a projection may be provided at a position facing the switching button, and the rotation may be performed around this point.

FIG. 5 (a) is a subject image obtained by two photographings, a normal mode photographing A and a shift mode photographing B. Both subjects are shifted by 2.44 μm in the direction of arrow S, for example. When these two subject images are combined, 3.2 million pixels have the same resolution as the image of 12.8 million pixels shown in FIG. 5B.

FIG. 5C shows a screen A of the photographing A in the normal mode.
5A and 5B show a screen B of the shooting B in the shift mode.
Are complemented by A and B), and the resolution can be improved as described above.

The relationship between the shift amount (angle) of the optical axis and the shift amount (distance) of the subject image on the solid-state image sensor is determined by the focal length of the lens. Therefore, in the case of a zoom lens, if the rotation angle of the prism is changed in accordance with the focal length, the zoom lens can be used in the entire zoom range. It is also possible to widen the rotation angle of the switching button and provide scales and stoppers according to the focal length.
There are two ways.

By changing the shift amount, various synthesized images can be obtained. For example, shifting in the horizontal direction increases the resolution in the horizontal direction. This is made possible by adding a mechanism for rotating the entire pixel shift function unit. Further, if the shift amount is divided, sequentially shifted and then resolved and combined, the resolving power is improved several times.

FIG. 6 is a view showing the structure of the prism 21 which is a pixel shift element. The prism 21 is shown in FIG.
As shown in FIG. 6A, a single unit may be used, or FIGS.
As shown in (c), a composite prism in which two prisms having a small angle are combined may be used. When a composite prism is used, the angle of a single prism can be increased, and a prism having a small angle, which is difficult with a single prism, can be easily manufactured, and chromatic aberration can be eliminated.

In such a composite prism, the shift amount may be changed by rotating the pixel unit together when the pixel is shifted. Alternatively, the shift amount may be changed by rotating a part of the compound prism. In this case, as shown in FIG. 6 (c), two prisms having the same shape can be arranged by rotating them by 180 degrees. When the part is rotated, the angle can be increased by increasing the angle of one prism. The angle can be reduced.

According to this embodiment, a high-quality image of, for example, 12.8 million pixels can be obtained at low cost and easily.
Moreover, since the pixel shift adapter 2 is placed in front of the digital still camera 1, the compactness of the digital still camera 1 during normal shooting is not impaired.
If the digital still camera 1 has a pixel shift function, an ultra-high quality still image equivalent to 25.6 million pixels can be obtained at low cost by combining the function with the function. Also, the present invention is applicable to compact VHS-C and DVC still images.

In the above embodiment, the pixel shift adapter 2 separate from the digital still camera 1 is arranged in front of the digital still camera 1. However, as shown in FIG.
The digital still camera 1 is mounted on the pedestal 201 of the pixel shift adapter 2, and the pixel shift adapter 2 is mounted.
Can be reliably arranged at a predetermined position in front of the digital still camera 1. In addition, as shown in FIG. 7B, there is also a configuration in which a separate type is provided.

FIG. 8 shows an embodiment in which the pixel shift adapter 2 is attached to the digital still camera 1 to increase the resolution. The manual selection mode button 15 for selecting the normal mode and the high resolution mode is operated by the digital still camera. Camera 1
The operability can be improved.
In the high-resolution mode, a function that can be combined at an appropriate time can be added by adding an electrical marking to a captured image.

FIG. 9 is the same as the embodiment shown in FIG. 8, but in this embodiment, when the pixel shift adapter 2 is attached to the digital still camera 1, the switch 16 is automatically pushed by the adapter 2 and the high resolution mode is set. , The operability can be further improved as compared with the embodiment of FIG.

In the above embodiment, the switching button 22 for changing the pixel shift amount is manually rotated as shown in FIG. 10A, but is electrically driven as shown in FIG. 10B. The operability can be improved as a configuration for rotating. Further, as shown in FIG. 10C, the operability can be further improved by controlling the electric pixel shift operation by operating the main body of the digital still camera 1. For example, in the case of a zoom lens, the amount of rotation can be controlled according to the focal length of the lens.

FIG. 11 is a diagram showing a configuration of a solid-state imaging device according to a second embodiment of the present invention. In this example, FIG.
A pixel shift adapter 2 is integrally attached to the digital still camera 1 as shown in (a), and a prism 21 as a pixel shift element is attached to and detached from the pixel shift adapter 2 as shown in FIG. It is freely attached.

Next, the operation of this embodiment will be described.
When performing normal shooting, the pixel shift element (prism)
21 is taken with the pixel shift adapter 2 removed. To perform high-resolution shooting, first, shooting is performed in the normal mode with the pixel shift element (prism) 21 removed from the pixel shift adapter 2, and then the pixel shift element 21 is attached to the pixel shift adapter 2 and the same. Re-photograph the subject in shift mode.

Thereafter, by synthesizing the two captured images, a high-resolution captured image can be obtained.
Has the same effect as the first embodiment shown in FIG. In particular, in this example, since the configuration is simple, high-resolution imaging can be performed at lower cost.

FIG. 12 is a diagram showing a configuration of a solid-state imaging device according to a third embodiment of the present invention. This embodiment has a pixel shift adapter 2 using a mirror 24 as a pixel shift element in front of a lens 11 of the digital still camera 1. The pixel shift adapter 2 has a switching button 22 for switching between the normal mode and the shift mode.

Next, the operation of this embodiment will be described with reference to FIG. The mirror 24 is disposed in front of the lens 11 at a predetermined angle (45 degrees). The tilt of the mirror 24 is controlled by rotating the switching button 22 so that the mirror 2
4 is changed. As a result, the mirror 24 is tilted 0.0115 degrees as compared with the normal mode,
CCD as if the subject shifted from 100A to 100B
The image formation on the pixel 12 is shifted, and the pixel shift photographing can be performed in the following, and the same effect as in the first embodiment is obtained. However, since the mirror 24 is used as the pixel shift element,
A high-quality image without chromatic aberration can be obtained. The same effect can be obtained by rotating the mirror in an in-plane direction slightly inclined with respect to the mirror 24.

FIG. 14 is a diagram showing the configuration of a solid-state imaging device according to a fourth embodiment of the present invention. In front of the lens 11 and the collimator lens 13 of the digital still camera 1,
A pixel shift adapter 2 using a parallel plate 25 made of plastic or the like as a pixel shift element is arranged. The pixel shift adapter 2 has a switching button 22 for operating the pixel shift mechanism 27 to tilt the parallel plate 25 with respect to the optical axis.

Next, the operation of this embodiment will be described with reference to FIG. By turning the switching button 22, the pixel shift mechanism 27 is moved to A or B, and the parallel plate 25 at the normal photographing position is moved to the shift photographing position (broken line in the figure) to be tilted 2.36 degrees. As a result, the subject becomes 10
The image on the CCD 12 is shifted as if it were shifted from 0A to 100B, and pixel shift shooting can be performed.
This embodiment has the same effect as that of the first embodiment, but in particular, since the parallel plate 25 is used as the pixel shift element, a high-quality image with little chromatic aberration can be obtained. Similar processing can be obtained by rotating the parallel plate in an in-plane direction slightly inclined with respect to the parallel plate.

FIG. 16 is a diagram showing a configuration of a solid-state imaging device according to a fifth embodiment of the present invention. This example has a configuration in which a pixel shift adapter 2 to which two pixel shift elements 21-1 and 21-2 arranged in plane parallel can be mounted in front of a lens 11 of the digital still camera 1. .

Next, the operation of this embodiment will be described.
First, shooting A is performed in the normal mode of the pixel shift elements 21-1 and 21-2, and shooting B is performed in the shift mode of 21-1.
I do. Next, photographing C is performed in the 21-1 normal and 21-2 shift mode, and photographing D is performed in the 21-1 and 21-2 shift mode. As a result, as shown in FIG. 17, the subject shifts as indicated by A, B, C, and D.
On D, screens A, B, C, and C shown in FIG.
D is obtained, and when these are combined, an ultra high resolution screen as shown in FIG. 18B is obtained.

As a result, in the present embodiment, higher-resolution shooting can be easily and inexpensively performed as compared with the above embodiment.

FIG. 19 is a diagram showing a configuration of a solid-state imaging device according to a sixth embodiment of the present invention.

In the example shown in FIG. 19A, a pixel shift adapter 2 is attached to a digital still camera 1 having no ordinary pixel shift photographing function, and a personal computer 3 is connected to the digital still camera 1. .

Also in this case, one image is shot in the normal mode and one image is shot in the shift mode to obtain two images. A synthesizing function for synthesizing the two images to create a high-resolution image Is not in the digital still camera 1. Therefore, the two images are sent from the digital still camera 1 to the personal computer 3, and the combination is performed by the combination software and the personal computer 3, thereby obtaining a high-resolution image.

Similarly, FIG. 19B shows a configuration in which two photographed images are made to be performed by the combination software and the printer 4.

According to the present embodiment, even if the digital still camera 1 does not have a normal pixel shift function, if the separate pixel shift adapter 2 and the personal computer 3 or the printer 4 are used, high-resolution shooting can be easily performed. It can be carried out.

[0047]

As described above in detail, according to the solid-state imaging device and the resolution conversion device of the present invention, the resolution of a photographed image can be easily increased without making the device expensive and without losing compactness. be able to.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a solid-state imaging device according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a rotation operation of the prism shown in FIG.

FIG. 3 is a diagram illustrating a shift amount of a prism illustrated in FIG. 1;

FIG. 4 is a view for explaining a pixel shift photographing operation by the apparatus of FIG. 1;

FIG. 5 is a diagram illustrating the principle of obtaining a high-resolution captured image using the pixel shift adapter of the device shown in FIG.

FIG. 6 is a diagram showing a structural example of a prism which is a pixel shift element shown in FIG.

FIG. 7 is a diagram illustrating an embodiment of the pixel shift adapter illustrated in FIG. 1;

FIG. 8 is a view showing another embodiment of the pixel shift adapter shown in FIG. 1;

FIG. 9 is a view showing still another embodiment of the pixel shift adapter shown in FIG. 1;

FIG. 10 is a diagram illustrating an example of an operation configuration of a switching button illustrated in FIG. 1;

FIG. 11 is a diagram illustrating a configuration of a solid-state imaging device according to a second embodiment of the present invention.

FIG. 12 is a diagram illustrating a configuration of a solid-state imaging device according to a third embodiment of the present invention.

13 is a diagram illustrating a pixel shift operation by the mirror shown in FIG.

FIG. 14 is a diagram illustrating a configuration of a solid-state imaging device according to a fourth embodiment of the present invention.

FIG. 15 is a diagram for explaining a pixel shift operation by the parallel plate shown in FIG. 14;

FIG. 16 is a diagram showing a configuration of a solid-state imaging device according to a fifth embodiment of the present invention.

FIG. 17 is a diagram illustrating a shift of a subject when pixel shift shooting is performed by the apparatus in FIG. 15;

FIG. 18 is a diagram illustrating the principle of obtaining a high-resolution captured image when pixel shift imaging is performed by the apparatus in FIG.

FIG. 19 is a diagram illustrating a configuration of a solid-state imaging device according to a sixth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Digital still camera 2 Pixel shift adapter 3 Personal computer 4 Printer 11 Lens 12 CCD 13 Collimator lens 15 Selection mode button 16 Switch 21 Prism 21-1, 21-2 Pixel shift element 22 Switching button 24 Mirror 25 Parallel plate 27 Pixel shift mechanism 201 pedestal

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hideki Tenkaji 3-12-12 Moriyacho, Kanagawa-ku, Yokohama-shi, Kanagawa Japan F-term (reference) 5C022 AA13 AB43 AB68 AC42 AC51 AC61 CA01 CA02 CA07 5C024 AX01 BX01 BX06 CX39 CY20 CY33 DX04 DX07 DX08 EX47 GY01 HX58

Claims (4)

[Claims] 1. A solid-state imaging device having a function of synthesizing a plurality of captured images taken by a pixel shift function, wherein the solid-state imaging device is disposed in front of a lens of the solid-state imaging device and shifts an optical axis of light incident on the lens. A solid-state imaging device comprising a conversion device having a pixel shift element. 2. The solid-state imaging device according to claim 1, further comprising means for inserting and removing said pixel shift element with respect to said conversion device. 3. The solid-state imaging device according to claim 1, wherein the pixel shift element is a compound prism formed by combining two or more prisms. 4. A resolution conversion device comprising a pixel shift element capable of displacing an optical axis in a housing, wherein said pixel shift element is a composite prism formed by combining two or more prisms. A resolution converter having means for rotating at least one of the single prisms forming the composite prism.