JPH042279A - Electronic still camera - Google Patents

Abstract

PURPOSE:To display a picture onto a display means in real time by providing a means outputting a high definition picture signal and a means outputting a low definition picture signal, selecting the outputs properly, inputting the result to a display means and inputting a high definition picture signal to a picture recording means. CONSTITUTION:Either a high definition picture signal outputted from a line sensor 18 of a 1st picture signal output means or a low definition picture signal outputted from an area sensor 13 of a 2nd picture signal output means is selected and inputted to an electronic view finder 9 of a display means, where the selected signal is displayed. Moreover, the high definition picture signal is recorded and the low definition picture signal is inputted to the electronic view finder 9 of the display means. Thus, the picture is displayed in real time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an electronic still camera using an image sensor such as a CCD sensor.

[Prior Art] Conventionally, only an optical finder is generally used as a finder for an electronic still camera.

In addition, in a normal movie video, a single CCD sensor is used, and the digital image signal obtained from this CCD sensor is reproduced and displayed on an electronic viewfinder (EFV). Record on tape.

Furthermore, JP-A-63-174028 discloses a camera that has both movie video and still camera functions, but the image sensor is selectively used for displaying an electronic viewfinder and recording images. Configuration not shown.

C] Problems to be Solved by the Invention] By the way, in order to obtain electronic still video images as high in definition as silver halide photography, an image sensor with a high number of pixels is required. For example, A4 size, 400 dpi (dots/inch), approximately 16 million pixels, 300 dpi
Approximately 9 million pixels are required as a color image, and three times as many pixels as these are required for a color image. Further, electronic image data is generally digital data because it is easy to handle, process, noise resistant, and has no data deterioration, and requires 8 bits for gradation reproduction.

One way to obtain high-definition electronic images is to finely scan a line sensor with a high number of pixels (assuming a line sensor with 4096 pixels is scanned in 4096 steps, and
(equivalent to 0,000,000 pixels), or a method of photographing by shifting the pixels of an area sensor with a small number of pixels (high-definition compatible CCD (2
If you expose 3 million pixels) and 4 times (to make it look like a pixel), 8
(equivalent to 1,000,000 pixels).

In any of the above methods, only scanning and pixels are required, so it takes several to several tens of seconds to take a picture. Further, even if an area sensor that obtains high-definition electronic images is created, it takes time to read out pixel data I- due to the large number of pixels. To do this at high speed requires complicated and expensive equipment. Therefore, an inexpensive device that uses a sensor that obtains high-definition electronic images cannot output images in real time, while a camera must have a viewfinder. cannot obtain images in real time, so when using an electronic viewfinder,
The drawback is that the image is displayed on the viewfinder with a slight delay from the camera movement. Regarding this point, when using an optical viewfinder, there is no time lag between the movement of the camera and the image displayed on the viewfinder, but it is inconvenient because it is not possible to decide on the shooting scene while displaying the image on a large external monitor. be.

The present invention solves the above problems by providing a low-definition sensor for the electronic viewfinder and external monitor in addition to the sensor that obtains high-definition electronic images. To provide an easy-to-use electronic still camera that can display images on an external monitor.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a first image signal output means for outputting a high-definition image signal, and an image signal output from the first image output means. a second image signal output means for outputting an image signal with lower definition than that of the first image signal output means; an image recording means for recording the image signal output from the first image signal output means; and the first or second image signal. The electronic still camera is equipped with display means that selectively inputs image signals output from an output means and displays them as images.

Further, in the above configuration, a line sensor having a °ζ scanning mechanism or an area sensor having a pixel shifting function is used as the first image signal output means, and an area sensor is used as the second image output means.

In the present embodiment described below, the line sensor 18 having the sensor scanning mechanism 19 corresponds to the first image signal output means, and the area sensor 13 corresponds to the second image signal output means.

[Operation] According to the above configuration, either the high-definition image signal output from the first image signal output means or the low-definition image signal output from the second image signal output means is selected. The signal is input to the display means and displayed, and the former high-definition image signal is recorded as an image. By inputting the latter low-definition image signal to the display means, the image is displayed in real time, making it easy to determine the composition of the photograph.

[Embodiment 1] An embodiment of the electronic still camera of the present invention will be described below with reference to the drawings.

FIG. 1 shows the appearance of the camera according to this embodiment.

The electronic still camera 1 includes a camera housing 2, a main switch 3 provided in the housing 2, a video output selection switch 4 for an auxiliary photographing system (hereinafter referred to as photographing system 1), and a main photographing system (hereinafter referred to as photographing system 2). image output selection switch 5 and image recording switch 6, photographing lens 7, etc., magnetic tape insertion section 8 for image recording, and electronic viewfinder (hereinafter referred to as EVF).
) 9, external monitor 10, and this external monitor 10.
and a cable 11 that connects the camera 1. Note that the monitor 10 can be removed when not needed.

FIG. 2 is a block configuration diagram including circuits within the camera body. In this figure, the optical system 26 consists of an image lens 7, an aperture (not shown), a mirror, etc.
The subject image is divided into an area sensor 13 and a line sensor 18. The area sensor 13 is a photographing sensor of the circuit 12 of the photographing system 1, and the image signal of the subject obtained by the area sensor 13 is amplified by the amplifier circuit 14, and then subjected to processing such as filtering in the processing circuit 15. After being converted into a signal that can be output to the EVF 9 and monitor 10 in the reproducing circuit 16, the signal is output to the EVF 9 and monitor 10.

On the other hand, the line sensor 18 is a photographing sensor of the circuit 17 of the photographing system 2, and is scanned by the sensor scanning mechanism 19, so that it can obtain a higher definition image signal than the image signal of the subject obtained by the area sensor 13. ing.

This image signal is amplified by an amplifier circuit 20, then converted to digital data by an A/D converter 21, and then processed by a processing circuit 22.
It is temporarily stored in the memory 23 through processing such as filter processing, and is also stored in the EVF 9 and monitor 1 in the reproducing circuit 25.
After being converted into a signal that can be output as 0, it is output to the EVF 9 and monitor 10.

Further, the image data stored in the memory 23 can be sent to a recording device 24 and recorded on a recording medium such as a magnetic tape.

A series of operations in the above configuration are performed by a control section 28 that operates in response to signals from an operation section 27 consisting of various switches provided on the camera housing 2.

FIG. 3(a) does not show the first embodiment of the photographing operation using the present camera 1, but is a flowchart (2).

When the main switch 3 is turned on and the power is turned on to the camera (step Sl and below, it is simply written as 81. The same applies below).
, the control unit 28 turns the imaging system 1 (circuit 12) ONL (8
2) Set the imaging system 2 (circuit 17) to 0FFL (33),
Turn on EVF9 and monitor 10 (S4),
Images from a photographing system 1 are displayed on a monitor 9 and a monitor 10 in real time. The photographer can decide on the composition while viewing the image displayed on this screen.

Next, it is checked whether the selection switch 5 of the photographing system 2 has been turned on (S5), and if it is determined that it has not been turned on, it is checked whether the image recording switch 6 has been turned on (S5).
S6). When the image recording switch 6 is turned on, the shooting system 1
0FFL (37), shooting system 2 ONL, (S8)
, performs image recording (S9), and proceeds to step 813 described later. Through the above processing, the image from the photographing system 2 is displayed on the EVF 9 and the monitor 10, and the image from the photographing system 2 is recorded by the recording device 24 (S9). Note that the flow proceeding from S5 to 86 is for the case where image recording is performed directly after determining the composition in the photographing system 1. If the image recording switch 6 is not turned on in S6, the above process is not performed and S1
Proceed to step 3.

Further, if it is determined in S5 that the selection switch 5 is turned on, the photographing system 1 is turned off. (510)
, the shooting system 2 is set to 0NL (S11.), thereby EVF9
And the image from the photographing system 2 is displayed on the monitor 10. Next, it is checked whether the image recording switch is turned on (S12), and if it is turned on, the process proceeds to S9.
Photograph taken with photographic system 2 (recorded in the FA era).

If the image recording switch 6 is not turned on in S6 and S12, or after the image recording process in S9, proceed to S13 and check whether the main power has been turned off. If it has not been turned off, return to S5, and if it has been turned off, the EVF9 Then, the monitor 10 is set to 0FFL (Sl, 4), and the operation ends.

FIG. 3(b) is a flowchart showing the second embodiment. This embodiment is the same as the first embodiment, except that the determination as to whether the selection switch 6 of the photographing system 2 is turned on or not and the subsequent flow are removed from the first embodiment. Since high-definition image information output from the photographing system 2 is hardly needed until image recording is performed, in that case, this second embodiment may be used.

Steps 81 to S4 are the same as in the first embodiment, and immediately after S4, it is checked whether the image recording switch 6 is turned on (36).
, if it is turned on, the process proceeds to S7 and later, and E
The image of the photographing system 2 is displayed on the VF 9 and the monitor 10, and the image produced by the photographing system 2 is recorded by the recording device 24.

As described above, according to this configuration, when determining the composition by displaying an image of the subject in real time on the EVF 9t or monitor 10, shooting system 1 is selected and the image is displayed in high definition, although not in real time. If you wish to do so, you can select the photographing system 2 to smoothly perform photographing. In either case, the imaging system 2 capable of high-definition imaging is used for the main imaging.

In both the first and second embodiments, the signal from the imaging system that is turned ON is input to the EVF 9 and the monitor 10 and displayed, but the present invention is not limited to this. It never happens.

For example, images may be input to the EVF 9 and monitor 10 from the imaging system 1 even during image recording, and images captured only for a predetermined period may be input from the imaging system 2 after imaging. Alternatively, a manual switch may be provided, and only while this switch is operated, the shooting system 2 to EVF 9
The image may also be input to the monitor 10.

In this embodiment, one optical system is used to capture images with two image sensors 13 and 18, but the image sensor 13 of the image sensor 1 for the EVF and monitor has a small number of pixels, and is used for the actual shooting. Since the image sensor 18 of the photographing system 2 has a large number of effective pixels, the sensor size of the latter is generally larger than that of the former. It is desirable for these sensors to have the same angle of view when viewing the same image, but in a monocular system like this embodiment, this is not possible with a single photographing lens.

FIG. 4 is a diagram showing this situation. FIG. 4(a) corresponds to the imaging system 1, and FIG. 4(b) corresponds to the imaging system 2. In FIG. 4(a), the image on plane A has a focal length Mf1
The lens 31 forms an image on eight surfaces, and the angle of view at that time is θ. The image of this A plane is formed as a larger image than that shown in FIG. 4(a) while maintaining the angle of view θ, that is,
In order to form an image on the 0 plane in FIG. 4(b), the focal length f2(
>fl) lens 32 is required.

FIGS. 5 and 6 are diagrams showing the principle of a method for solving the above-mentioned problems. Figure 5 shows a case where the lens 31 in Figure 4(a) is used, and by inserting a concave lens 33 with a focal length of Mf3 between the lens 31 and the imaging plane, a state equivalent to that in Figure 4(b) is obtained. is obtained.

On the other hand, FIG. 6 shows a case where the lens 32 of FIG. 4(b) is used, and a condenser lens 34 is placed on the imaging plane C, and a re-imaging lens 35 with a focal length f4 is used to focus the image on the B' plane. A state equivalent to that shown in FIG. 4(a) is realized.

FIG. 7 is a diagram when the method shown in FIG. 5 is implemented in an actual optical system. In FIG. 7, the movable mirror 36 is indicated by the arrow
By moving in the direction of , the optical path can be changed.

In the state shown in FIG. 7, the image of the A plane passes through the lens 31, is reflected by the mirror 36, passes through the lens 33, and is imaged on the 0 plane. The line sensor 18 scans and photographs this C plane in the direction of the arrow ■. On the other hand, when the mirror 36 is raised, the image of the A plane passes through the lens 31 and is formed on the area sensor 13 on eight planes.

FIG. 8 is a diagram when the method shown in FIG. 6 is implemented in an actual optical system. In FIG. 8, a mirror 37 has the same function as the mirror 36 in FIG. 7, and moves in the direction of the arrow {circle around (2)}. In the state shown in Fig. 8, the image of the A plane passes through the lens 31 and the mirror 37, and forms an image on the C' plane, which is equivalent to the 0 plane. 'The image is re-imaged on the on-screen area sensor 13. On the other hand, mirror 37
If the optical path is lowered and the optical path cannot be changed, the image of the A plane passes through the lens 31 and is focused on the 0 plane, and the line sensor 18 scans and photographs the C plane in the direction of the arrow (■).

The mirrors 36 and 37 shown in FIGS. 7 and 8 move in response to the operation of the selection switches 4.5 of the photographing systems 1 and 2 shown in FIG. 1 to change the optical path.

Further, in the examples of FIGS. 7 and 8, the mirrors 36 and 37 may be half mirrors, in which case there is no need to move the mirrors.

In this embodiment, the sensor 18 of the photographing system 2 is a line sensor, but it is not limited to this, and may be a multi-line sensor or a system in which the area sensor is shifted by pixel. This applies to imaging systems that require time to capture images due to the need for scanning, and are difficult to monitor in real time.

In addition, in this embodiment, images are formed using the same optical system (single-lens type) for the imaging systems 1 and 2, but the present invention is not limited to this, and it is also possible to use separate optical systems for the two-lens type. good.

[Effects of the Invention] As is clear from the above description, the invention of claim 1 includes a means for outputting a high-definition image signal and a means for outputting a low-definition image signal. The output is appropriately selected and inputted to the display means, and a high-definition image signal is inputted to the image recording means. Therefore, in order to capture high-definition images with conventional electronic still cameras,
When displaying the same image on a display means such as an electronic viewfinder or an external monitor, it is difficult to display it in real time because signal processing takes time, which is inconvenient for deciding the composition. By switching the image signal to a low-definition image @ signal, the image can be displayed on the display means in real time, making it easier to decide on the composition, and in that case, the actual shooting will record a high-definition image signal. can do.

Further, according to the invention of claim 2, since the image signal output means for performing the actual imaging performs mechanical scanning, it is possible to increase the effective number of pixels of the current area sensor and line sensor. High-definition images can be taken at a relatively low cost.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of an embodiment of the electronic still camera of the present invention, FIG. 2 is a circuit block diagram of the camera, and FIG.
) and (b) are the first and second embodiments of the present camera control method.
Flowchart showing an example, FIGS. 4(a) and (b) are diagrams showing the optical path of the optical system when separate lenses are used, and FIGS. 5 and 6 are methods for adjusting the size of image formation. , FIG. 7, and FIG. 8 are diagrams showing examples of the arrangement of optical paths, lenses, and mirrors used in an actual optical system. 1... Electronic still camera, 4... Video output selection switch for auxiliary shooting system, 5... Video output selection switch for main shooting system, 9... Electronic viewfinder (display means) 1
0... External monitor (display means) 13... Area sensor (second image signal output means), 18... Line sensor (first image signal output means), 19... Sensor scanning mechanism, 24...Recording device. Figure 1 Applicant: Agent for Minolta Camera Co., Ltd.
Patent Attorney Yasuo Itaya Figure φ--0 ゛・C Prisoner

Claims (2)

[Claims] (1) A first image signal output means that outputs a high-definition image signal; and a second image signal output means that outputs an image signal that is lower in definition than the image signal output from the first image output means. and an image recording means for recording the image signal outputted from the first image signal outputting means, and selectively inputting the image signal outputted from the first or second image signal outputting means and recording it as an image. An electronic still camera characterized by comprising: a display means for displaying a display; (2) A line sensor having a scanning mechanism or an area sensor having a pixel shifting function is used as the first image signal output means, and an area sensor is used as the second image output means. Electronic still camera.