JPH01194764A - Electronic camera - Google Patents

Abstract

PURPOSE:To set an object information detecting are at an intended position on a screen without making a device large by providing a means to generate the position signal of the object information detecting area on a photographing picture selected by a panel switch. CONSTITUTION:The video signal of an object is sent to a finder display part 10. At this time, when the depressing operation of the panel switch 9 for an area where the object desired to perform range finding and photometry exists is performed, a switch is turned ON, and a signal is generated. Corresponding to the signal, the selective output of the video signal inputted from a pre-amplifier 4 to an AF circuit 18 and an AE circuit 19 is performed at a gate circuit 17. At the AF circuit 18, the smoothing of the video signal and the extraction of a high frequency component are performed, and the travel control of a photographing lens 1 via a motor 7 is performed so as to maximize the high frequency component. Also, at the AE circuit 19, the smoothing of the video signal and the aperture state control of a diaphragm via an IG meter 6 so as to set the voltage of the video signal at the optimum value are performed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention relates to an improvement in an electronic camera having an image sensor, such as a video camera, which performs focus control and exposure control using a video signal.

(Background of the Invention) Conventionally, in a video camera that uses an imaging signal to perform focus control and exposure control, for example, focus control is performed using a video signal that passes through a certain distance measurement area near the center of the screen. Exposure control has been performed using the entire screen as a photometric area and a video signal passing through the area. However, these methods had the following drawbacks.

In other words, in terms of focus control, since the camera can only focus near the center of the screen, if you want to focus on a subject around the screen, you have to manually adjust the focus. Regarding exposure control, it was necessary to manually adjust exposure compensation when there was backlight or when there was a highly bright area in the screen.

In view of this, in recent years, cameras have been proposed in which the screen is divided into a plurality of areas, and the distance measurement area and photometry area within the screen can be set at arbitrary positions from the outside.

An example of a device having this type of function is shown in FIGS. 4 and 5. FIG. 4 is a perspective view of the joystick 2o for instructing the movement direction of the distance measurement area and photometry area within the screen, and FIG. A microcomputer 21 is shown that outputs position signals of the distance area and the photometry area to a known gate circuit.

When the lever of the joystick 20 is pushed in the A direction, switch a closes, and then the lever is moved to B in the same manner.

Switch b corresponding to C5 or D direction.

c and d are closed, and by closing these switches, a high level signal is input to the microcomputer 21.

The microcomputer 21 receives a high level signal and a horizontal synchronization signal HD% and a vertical synchronization signal (2) which are input in conjunction with the above-mentioned operations. A position signal is generated based on the above, and the position signal is output to a gate circuit (not shown). As a result, as shown in FIG. 6, the distance measurement area and the photometry area, that is, the subject information detection area 23, are moved to any position within the screen 22, allowing focus control and exposure for the subject intended by the photographer. It becomes possible to perform control reliably.

However, when this type of device is added to a camera, it not only increases the size of the camera, but also poses a risk of making it less portable.

(Object of the Invention) An object of the present invention is to solve the above-mentioned problems, and to be able to set a subject information detection area at an intended position within the screen by external operation without causing increase in size or deterioration of portability. Our goal is to provide electronic cameras.

(Features of the Invention) In order to achieve the above object, the present invention comprises a display means for externally displaying a subject image projected on a photographing screen, and a transparent member that covers the display screen of the display means, and a transparent member that covers the display screen of the display means. position signal generating means for generating a position signal of a subject information detection area within a photographing screen based on a signal generated in the panel switch when a detection area is selected; The present invention is characterized in that it is configured integrally with the display means, and the display on the display means can be observed and any subject information detection area within the display screen can be selected through the panel switch.

(Embodiments of the Invention) Hereinafter, the present invention will be described in detail based on illustrated embodiments.

FIG. 1 is a block diagram showing one embodiment of the present invention. In the figure, 1 is a photographing lens, 2 is an aperture, 3 is an image sensor such as a CCD, 4 is a preamplifier that amplifies the electrical signal from the image sensor 3, 5 is a signal processing circuit, and 6 is an IG that drives the aperture 2. 7 is a motor for driving the photographic lens, 8 is a liquid crystal display that displays the subject image based on the input video signal, and 9 is a panel switch (details) consisting of a transparent member attached to the front of the liquid crystal display 8. will be described later), which together with the liquid crystal display 8 constitutes a finder display section 10. 11 is a memory circuit for storing the position of the area selected by operating the panel switch 9 on the screen; 12 is a character generator; 13 is a clock generator; 14.15 is a counter; 16 is a matrix circuit; 18 is a gate circuit that selects a passing video signal according to the pulse (position signal) from the matrix circuit 16; and AF 18 is an AF that controls the drive of the motor 7 based on the high frequency component of the video signal selected by the gate circuit 17. circuit, 19 is gate circuit 17
The IG based on the luminance component of the video signal selected in
This is an AE circuit that controls the drive of the meter 6.

FIG. 2(a) is a front view of the panel switch 9,
The screen (the display screen of the liquid crystal display 8) is divided into 12 areas, and any area within the screen can be selected by a pressing operation. In other words, as shown in FIG. 3, the area E-P forming each panel switch operating section 9a is equipped with switches e-p, and by performing a selection operation (pressing operation) on an arbitrary area, the switch e-p is provided. A switch corresponding to the area is turned on, a high-level signal is generated, and the selected area on the screen is memorized.

In addition, this panel switch 9, as shown in FIG. 2(b),
It is attached to the front of the liquid crystal display 8 that displays the subject image, and the photographer selects an arbitrary distance measurement area and photometry area while viewing the subject image displayed on the liquid crystal display 8 through the panel switch 9. It turns out.

Next, the operation will be explained.

The object light that has passed through the photographic lens 1 enters the image sensor 3, where it is converted into an electrical signal, sent to the signal processing circuit 5 via the preamplifier 4, and output as a video signal. This video signal is sent to a liquid crystal display 8 forming a part of the finder display section 10, and displayed as a subject image on the liquid crystal display 8. This subject image is provided for observation through the panel switch 9 as described above.

Here, the subject for which you want to perform distance measurement and photometry is shown in Figure 2 (a).
Assume that the object is in an area J shown in , and a pressing operation is performed on the area J. Then, switch j is turned on and a high level signal is generated, and the fact that area J has been selected is stored in memory circuit 11, and the information is output to matrix circuit 16. This information remains stored until the next new information is input even if the pressing operation on the area J is stopped and the switch j is turned off. Matrix circuit 1
6 outputs a position signal to guide only the video signal passing through the area designated by the memory circuit 11 to the AF circuit 18 and AE circuit 19.

That is, a pulse that is at a high level is output for a predetermined period within the vertical period and a predetermined period within the horizontal period.

These are the clock from the clock generator 13, the horizontal synchronization signal H8, and the vertical synchronization signal ■. It can be specified by the count amount from the counter 14 and the counter 15 based on .

The gate circuit 17 to which the position signal as described above is input selectively outputs the video signal input from the preamplifier 4 to the AF circuit 18 and the AE circuit 19 in accordance with the position signal. That is, the video signal of the portion (region J) selected by the panel switch 9 is extracted as a signal for distance measurement and photometry, and is output to the AP circuit 18 and the AE circuit 19. As a matter of course, the position signal from the matrix circuit 16 and the position signal of the video signal from the preamplifier 4 are synchronized. The AP circuit 18 to which the video signal corresponding to the area J is input via the gate circuit 17 smooths the video signal and extracts the high frequency component, and sends the video signal via the motor 7 so that the high frequency component is maximized. Movement control of the photographic lens 1 is performed. Further, in the AE circuit 19, the aperture state of the diaphragm 2 is controlled via the IG meter 6 so that the video signal is smoothed and the video signal voltage reaches an optimum value.

Further, the signal from the matrix circuit 16 is also input to the character generator 12, and the signal from the matrix circuit 16 is also input to the character generator 12, and the signal from the matrix circuit 16 is input to the character generator 12.
In this case, area J) will be displayed.

According to this embodiment, the liquid crystal display 8 that displays the subject image and the display screen of the liquid crystal display 8 (which corresponds to the field of view of the photographing screen) can be divided into a plurality of areas and selected. It is configured integrally with the panel switch 9 to display the subject image and the selection area so that it can be seen in an overlapping manner, making it much more compact than, for example, a system in which the selection of the distance measurement area, etc. is performed using a joystick. This makes it possible to select a desired part of the subject by directly pressing on it while looking at the subject image, which greatly improves operability and makes it possible to provide a camera that is easy to use. Furthermore, since it can be made smaller as described above, it becomes a highly portable camera.

(Correspondence between the invention and the embodiments) In this embodiment, the image sensor 3 is the imaging means of the present invention,
The gate circuit 17 serves as gate means, and the AF circuit 18. The AE circuit 19 serves as a subject information detection means, the liquid crystal display 8 serves as a display means, the panel switch 9 serves as a panel switch, a clock generator 13, counters 14 and 15, and a matrix circuit 16.
correspond to the position signal generating means, respectively. Further, distance measurement information and photometry information correspond to subject information.

(Modification) In this embodiment, the distance measurement area and the photometry area are areas having the same size, but the invention is not limited to this. Also,
Although a camera has been described in which both the distance measurement area and the photometry area can be manually set, it is also possible to set only one or the other.

(Effects of the Invention) As explained above, according to the present invention, the present invention includes a display means for externally displaying the subject image projected on the photographing screen, and a transparent member that covers the display screen of the display means, and the subject information can be obtained by pressing the display means. position signal generating means for generating a position signal of a subject information detection area within a photographing screen based on a signal generated in the panel switch when a detection area is selected; Since the camera is integrated with the display means, and the display on the display means can be observed through the panel switch, and any subject information detection area can be selected within the display screen, there is no need for an increase in size or deterioration of portability. , it becomes possible to set the subject information detection area at the intended position within the screen by external operation.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 (
a) is a front view of the panel switch operation part forming part of the panel switch shown in Figure 1, Figure 2(b) is a perspective view of the finder display part shown in Figure 1, and Figure 3 is the panel switch shown in Figure 1. FIG. 4 is a perspective view showing an example of a conventional device for setting a subject information detection area, and FIG.
The figure is a circuit diagram showing its internal configuration, and FIG. 6 is a diagram illustrating a case where a subject information detection area is set by operating the apparatus shown in FIG. 4. 1...Photographing lens, 3...Image sensor,
8...Liquid crystal display, 9...Panel switch, 13...Clock generator, j4, 15...
... Counter, 16 ... Matrix circuit, 17 ... Gate circuit, 18 ... AF
Circuit, 19...AE circuit. Patent applicant Canon Co., Ltd.

Claims (1)

[Claims] (1) An imaging means that converts the subject light into a video signal, and a gate that guides the video signal passing through the subject information detection area to a subsequent stage according to a position signal within the shooting screen of the subject information detection area set by external operation. and a subject information detecting means for detecting subject information based on a video signal from the gate means, a display means for externally displaying a subject image projected on a photographing screen, and a display means for externally displaying a subject image projected on a photographing screen; It consists of a transparent member shaped to cover the display screen,
A panel switch that selects one of a plurality of subject information detection areas that can be selected within the photographic screen by a pressing operation, and generates a position signal of the subject information detection area within the photographic screen selected by the panel switch. An electronic camera characterized in that it is provided with a position signal generating means for generating a position signal.