JPH0214675A - Electronic image pickup device - Google Patents

Abstract

PURPOSE:To facilitate the picture corner setting by providing a photodetection area larger than the effective photodetection area of the 1st image sensor applied with the pickup of the 2nd image sensor and displaying peripheral information including the picked-up picture in a finder. CONSTITUTION:The 1st image sensor 3 has an area narrower than the entire image forming area on which an object image is formed by a pickup lens 2, that is, a photodetection area able to pick up a picture in the effective area while the effect by the aberration of lens is excluded. On the other hand, the 2nd image sensor 9 has a photodetection area nearly corresponding to the entire image forming area and the picture information including the peripheral area of the picture picked up by the 1st image sensor 3 is outputted to a finder. A visual field frame 13 with a size corresponding to the photodetection area of the 1st image sensor 3 is displayed on the pattern center on the pattern of a CRT 11 forming the finder. Thus, a photographer recognizes the pickup area including the peripheral area in the finder and uses the visual field frame as the picture corner setting zone.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electronic imaging device using a solid-state imaging device, and more specifically, to an electronic still camera equipped with an electronic viewfinder.

(Prior art) In recent years, objects have been imaged using solid-state imaging devices such as CCDs,
An electronic still camera has been proposed that records photoelectrically converted still images on a rotating, small-diameter sheet-like magnetic recording medium.

By the way, camera viewfinders mainly include single-lens reflex optical viewfinders, which bend part of the incident light from the subject that has passed through the photographic lens using a semitransparent prism, and guide it to the viewfinder, as well as small-diameter built-in monitor televisions. Alternatively, there is known an electronic viewfinder which is attached externally and which is used to view images by adding a video signal output from a camera.

In the electronic still camera, either of the former can be selected, but if the still camera is
Conventionally, many devices using an optical viewfinder have been proposed for reasons such as the fact that only shots are taken or that constantly driving a solid-state image sensor like a video camera consumes a lot of power.

(Problem to be Solved by the Invention) However, especially in the case of an optical finder, there is a large variation, and as a result, there is a drawback that the image actually captured cannot be sufficiently confirmed within the field of view of the finder. Furthermore, the TTL system requires large and complicated optical systems such as prisms and mirrors, and is therefore unsuitable for the above-mentioned still camera, which requires compactness.

On the other hand, in conventional electronic viewfinders, the imaging system sensor is also used as a finder sensor, so the range actually seen on the screen matches the field of view in the finder to provide the same spatial information.

Therefore, although the above-mentioned parallax does not occur, on the contrary, peripheral information on the outer periphery of the photographed image cannot be displayed in the finder, so it has the disadvantage that it is difficult to set the angle of view. Furthermore, since the solid-state image sensor of the imaging system with a large number of pixels is also used for the finder, it also has the disadvantage of high power consumption.

SUMMARY OF THE INVENTION An object of the present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an electronic imaging device equipped with an electronic viewfinder that displays peripheral information in a wider range than the photographic screen and allows easy setting of the angle of view.

Another object of the present invention is to provide an electronic imaging device including an electronic viewfinder with low power consumption.

(Means and Effects for Solving the Problems) That is, the above-mentioned object of the present invention is to provide an imaging recording system that captures an image of a subject incident through a photographing lens with a first image sensor and records an image signal on a magnetic recording medium. and a finder system for capturing and reproducing the subject image with a second image sensor, wherein the light receiving area of the second image sensor is formed larger than the effective light receiving area of the first image sensor. This is achieved by an electronic imaging device characterized in that surrounding image information including image information of an image sensor is displayed on an electronic display.

Since the second image sensor has a larger light-receiving area than the effective light-receiving area of the first image sensor that performs imaging, peripheral information including the captured image can be displayed in the finder.

Further, as a finder sensor for displaying a display, a few hundred pixels is sufficient, and therefore power consumption can be reduced compared to the case where it is also used as an imaging system sensor.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the concept of an electronic still camera according to the present invention.

In the figure, reflected light from a subject 1 enters the camera through a photographic lens 2. The imaging system projects the light incident into the camera onto a half mirror 4 disposed in the optical path, and further guides the light to the first image sensor 3 via the shutter 5. Further, the first image sensor 3 photoelectrically converts the subject image and outputs the image signal to a subsequent recording system.

The recording system is provided so that the photoelectrically converted signal is subjected to various signal processing in a signal processing circuit 6, further amplified in an amplifier 7, and then recorded on a floppy disk 8 via a magnetic head (not shown).

On the other hand, a part of the light projected onto the half mirror 4 is guided to a second image sensor 9 forming a finder system. The image signal photoelectrically converted by the second image sensor 9 is sent to the signal processing circuit 10 as in the case of the recording system.
After various signal processing through the 1-inch small CRT
II and displayed on the screen.

Note that other electronic displays, such as a liquid crystal display or a plasma display, may be used instead of the CRT.

Furthermore, in this embodiment, the output of the second image sensor 9 is also used for auto white balance (AWB) adjustment, and the imaged light is transmitted to the preamplifier 12.
The signal is sent to the color determination circuit 100 at the subsequent stage.

The color determination circuit 100 performs conventionally known automatic white balance adjustment, and is composed of a color encoder 101 that receives an image signal from the sensor 9, an automatic white balance circuit 102, and a color signal processing circuit 103. The output of this color determination circuit 100 is then supplied to a recording system signal processing circuit 6 for color correction.

The feature of the present invention is that the size of the light-receiving surface of the first image sensor 3 and the second image sensor 9, that is, the effective light reception of the element itself when 100% of the resolution of the element is utilized. The reason is that there are differences in the size of the areas.

The first image sensor 3 is provided with a high-resolution CCD image sensor having, for example, 400,000 pixels or more, and is provided from the entire imaging area (the shaded area in the figure) where the subject image is formed by the photographing lens 2. It has a light-receiving area in which an image can be captured in a narrow area, that is, an effective area (range shown by a solid line in the figure) in which the influence of lens aberration is excluded.

On the other hand, the second image sensor 9 has a light-receiving area that substantially corresponds to the entire imaging area, and thus has a wider range than the effective light-receiving area of the first image sensor 3, that is, the Image information including the peripheral area of the image captured by the first image sensor is output to the finder.

Note that the second image sensor 9 that outputs image information to the finder suffices to be an element with a lower resolution than the first image sensor 3, for example, a CMO device with several hundred pixels.
It can be provided by an S image sensor.

On the screen of the CRT II constituting the finder, a field frame 13 having a size corresponding to the light receiving area of the first image sensor 3 is displayed at the center of the screen. Image information corresponding to the image sensor is displayed, and image information corresponding to the peripheral area is displayed outside the viewing frame. Thereby, the photographer can recognize the photographing area including the peripheral area in the viewfinder and use the field frame as a field angle setting zone.

In the still camera configured as described above, the second image sensor 9 starts differential operation as a monitor (finder) by executing a switch or shutter operation.

Note that, since the second image sensor 9 has low power consumption, it may be provided so that the display state is always maintained by turning the switch "on".

When the second image sensor 9 projects the subject and surrounding information of the subject onto the CRT II, the photographer observes this, sets the angle of view, and then operates the shutter. As a result, the first image sensor 3 starts driving, performs imaging, and records image information for one frame on the floppy disk.

Note that in the above embodiment, only the output from the second image sensor is displayed on the CRT, but the CRT
The output from the first image sensor may be fitted into the field of view frame, so that image information within the field of view frame can be made into a clear image with higher resolution than surrounding information outside the field of view frame.

In addition, as shown in this embodiment, since the second image sensor is provided, surface information of the subject can be effectively utilized, and AW
In addition to the B monitor, AE and AF functions can be added to allow more advanced condition settings.

Furthermore, the present invention can also be used in movie cameras in addition to the electronic still cameras of the above-described embodiments.

(Effects of the Invention) As described above, according to the electronic imaging device of the present invention,
The second image sensor outputs even the peripheral area of the original imaging area onto the finder, thus forming a viewing angle setting zone and enabling a good imaging operation.

Further, by forming the field angle setting zone by providing a second image sensor, a prism or a complicated optical system is not required even in TTL photometry, making a compact design possible.

Furthermore, a low-resolution element can be used as the second image sensor, and therefore an electronic viewfinder with low power consumption can be realized.

[Brief explanation of the drawing]

FIG. 1 is a block diagram illustrating an electronic still camera according to an embodiment of the present invention. 1: Subject, 2: Photographic lens, 3: First image sensor, 4: Half mirror, 5: Shutter, 6: Signal processing circuit, 7: Amplifier, 8: Floppy disk, 9: Second image sensor, 10: Signal processing circuit, 11: Small CRT. :Preamplifier, :Field frame, Two-color judgment circuit (and 3 others)

Claims (1)

[Claims] An imaging recording system that captures an image of a subject incident through a photographic lens with a first image sensor and records an image signal on a magnetic recording medium; and a finder system that captures and reproduces the subject image with a second image sensor. a light-receiving area of the second image sensor is formed larger than an effective light-receiving area of the first image sensor, and peripheral image information including image information of the first image sensor is displayed on an electronic display. An electronic imaging device characterized by: