JPH06113184A - Camera device - Google Patents

Abstract

(57) [Abstract] [Purpose] An object of the present invention is to provide a camera device which can be manually focused with certainty. [Structure] A light receiving means 3 for photoelectrically converting a subject light image incident through an imaging optical system 1, and a focus state detecting means 8 for detecting a focus state based on an output signal from the light receiving means 3.
And the focus state display means 16 for displaying the transition state of the focus state detected by the focus state detection means 8, it is possible to confirm the focus condition of the subject, so that it can be manually operated. Focusing can be reliably performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera device for recording a photographed still image (still image).

[0002]

2. Description of the Related Art As a camera device, there are a silver salt camera and an electronic still camera, and the silver salt camera is adapted to form an image of light passing through an image pickup lens system on a film surface to expose it for recording. There is. The electronic still camera uses a CCD (Charge C
Oupled Device) is converted to an electronic signal by the electronic signal is recorded on a dedicated magnetic disk as image data. In such a camera device, a subject is confirmed by an optical viewfinder. Further, in the electronic still camera as described above, the subject is confirmed by an electronic viewfinder.

By the way, when taking a picture with such a camera device, usually, an automatic focus adjustment (autofocus) function is used for focusing. It becomes necessary and the entire device becomes large. In addition, it is difficult to focus on the subject of interest of the photographer. Therefore, the autofocus function itself may be omitted, or the function may be canceled and manual operation (manual operation) may be performed to focus with the naked eye. Then, in the past, when focusing is performed by a manual operation, the user manually performs an operation to see the clearest image while visually confirming an image displayed on an electronic viewfinder or the like.

[0004]

However, it is difficult to determine the optimum focus position (just focus position) with the naked eye, and there is a big problem that it is difficult to focus properly by manual operation.

Therefore, the present invention has been made to solve the above problems, and an object of the present invention is to provide a camera device capable of reliably focusing by a manual operation.

[0006]

The means of the present invention are as follows. That is, in order to solve the above problems, a camera device according to the present invention provides a light receiving unit (for example, a CCD) that photoelectrically converts a subject light image incident through an imaging optical system, and an output signal from the light receiving unit. An in-focus state detection unit that detects the in-focus state based on the in-focus state (for example, an integrator that obtains a contrast voltage that changes corresponding to the in-focus state from the image signal)
It is characterized by comprising a focus state display means (for example, a graph display section formed in the viewfinder) for displaying a transition state of the focus state detected by the focus state detection means.

[0007]

According to the camera device of the present invention, the focus status display means is configured to display the transition status of the focus status detected by the focus status detection means.
For example, if the focusing condition display means is provided in the viewfinder, the image in the viewfinder can be checked with the naked eye, and at the same time, the focusing condition can be checked by a graph display showing the transition state of the focusing state. Therefore, the focus can be surely adjusted by the manual operation.

[0008]

EXAMPLES Examples will be described below with reference to FIGS. FIG. 1 is a block diagram showing a schematic configuration of an electronic still camera according to an embodiment of the present invention.
Is a lens system that constitutes an imaging optical system, and the lens system 1 is configured to be movable along its optical axis by a manual focus mechanism 2 that is configured by a focusing ring or the like.

On the optical axis of the lens system 1, a one-chip CCD (Charge C
An coupled device) 3 is provided, and a captured image of a subject is formed on the image pickup surface of the CCD 3 via the lens system 1. Although not shown, the CCD 3 is designed so that its image pickup operation is controlled by a CCD driver whose operation timing is given by a timing generator.

The image signal picked up by the CCD 3 is output to an operational amplifier (Op-Amp) constituting the amplifier 4 and amplified to a predetermined level. Then, the amplified image signal from the amplifier 4 is output to the A / D converter 5 and converted from an analog signal to a digital signal. The digitized image signal is output to the image signal processing circuit 6, and the luminance signal YH and the color difference signals (CR (= RY), CB are output.
(= B−Y)) is extracted, the data of the luminance signal YH is output to the high-pass filter (HPF) 7, and only the high frequency component of the luminance signal YH is rectified by a rectifier circuit (not shown). It is output to the integrator 8 which constitutes the focus state detecting means.

The integrator 8 integrates the high frequency components of the rectified luminance signal YH to generate a DC voltage proportional to the contrast of the photographed image as a contrast voltage (contrast value).
The contrast voltage is calculated as a CPU (Central Processing Uni) for controlling each device of the electronic still camera.
t) 9 is output. Reference numeral 10 denotes an operation switch that inputs a control signal to the CPU 9 to operate each device, and a shutter release button, an exposure correction button, and the like are also a kind of the operation switch 10. The output signal from the CPU 9 is input to an encoder 14 described later via a bus.

On the other hand, the luminance signal YH extracted by the image signal processing circuit 6 and the color difference signals (CR (= RY), CB (=
(B-Y)) are stored in the image memory 11 and are recorded and stored in the form of magnetic signals on the dedicated magnetic disk by the recording device 12. Further, in order to output an image to the electronic viewfinder 15 described later (that is, to confirm the image from the CCD 3 with the electronic viewfinder 15 or to see the recorded image on the magnetic disk),
The luminance signal YH and the color difference signals (CR (= RY), CB (= BY)) stored in the image memory 11 are output to the D / A converter 13 and converted from digital signals to analog signals. , And is output as an image reproduction signal to an electronic viewfinder 15 which is a liquid crystal display device, for example, under the control of the encoder 14.

Then, based on the output signal corresponding to the contrast voltage from the CPU 9 described above, the encoder 14 generates a signal corresponding to the in-focus state of the lens system 1 by the manual focus mechanism 2, and the signal is generated. An image signal from the CCD 3 is combined with one corner of the electronic viewfinder 15 as shown in FIG. 2 and is displayed on a graph display section (bar graph) 16 which constitutes a focusing status display means. The contrast voltage (cotrast value) obtained by the integrator 8 changes with the movement of the lens system 1 by the operation of the manual focus mechanism 2 and becomes maximum at the in-focus position, and therefore corresponds to the contrast voltage. Changing the display of the bar graph of the graph display unit 16 from low level to high level based on the output signal It, by the bar graph portion 16, it is possible to visually recognize the transition state of focus state of the lens system 1 easily. The image reproduction signal converted into an analog signal by the D / A converter 13 is configured so as to be output to the outside through the encoder 14, so that the image can be displayed on a monitor television or the like.

The above is an example of the configuration of the electronic still camera according to the present invention, and its operation will be described below. First of all, when performing shooting by manual operation,
After turning on the power of the electronic still camera, the subject is captured in the electronic viewfinder 15. Then, the manual focus mechanism 2 configured by a focusing ring or the like is rotated to focus on the subject.
At this time, the image signal picked up by the CCD 3 through the lens system 1 is amplified by the amplifier 4 and then converted from an analog signal to a digital signal by the A / D converter 5,
It is output to the image signal processing circuit 6. Further, in the image processing circuit 6, the luminance signal YH is converted from the digitized image signal.
And color difference signals (CR (= RY), CB (= BY))
Of the luminance signal YH is output to the integrator 8 via the high-pass filter (HPF) 7,
The contrast voltage (contrast value) of the captured image is obtained. Then, a signal corresponding to the contrast voltage is output from the CPU 9 to the encoder 14, and a signal corresponding to the in-focus state generated by the encoder 14 is displayed on the graph display unit 16 in the electronic viewfinder 15.
Is displayed in. That is, if the manual focus mechanism 2 is operated while visually recognizing the image pickup screen displayed in the electronic viewfinder 15, CC associated with the movement of the lens system 1
Corresponding to the degree of focus on the image pickup surface of D3, the bar graph display of the graph display unit 16 in the electronic viewfinder 15 is gradually changed from the low level left end side in FIG. 2 to the high level right end side. Since it is moved to, it is possible to easily grasp the transition state of the in-focus state of the lens system 1, and even if the resolution of the captured image displayed on the electronic viewfinder 15 is low, it is difficult to visually check the focus condition. Even in this case, accurate and quick focusing can be performed.

When the shutter release button, which is one type of the operation switch 10, is pressed when the display on the graph display section 16 is maximized, the electronic shutter is operated and the image pickup screen is recorded through the image memory 11. The data is output to the device 12, magnetically recorded on a dedicated magnetic disk, and photographing is completed. In addition, when confirming the screen shot, or when viewing the image on a monitor TV or the like, the image signal recorded on the magnetic disk is read out to the image memory 11 by operating the predetermined operation switch 10, and D A / A converter 13 converts a digital signal into an analog signal, and an electronic viewfinder 1 via an encoder 14.
5 is output to the monitor 5, or is externally output to a monitor television or the like.

As described above, according to the electronic still camera of the present invention, the transition state of the focus state of the lens system 1 can be easily grasped by the display of the graph display section 16 in the electronic viewfinder 15. Therefore, even if the resolution of the captured image displayed on the electronic viewfinder 15 is low and it is difficult to visually check the focusing condition, accurate and quick focusing can be performed.

In the above embodiment, the case where the bar graph as shown in FIG. 2 is applied to the graph display unit 16 has been described, but the present invention is not limited to this, and the graph display unit 17 as shown in FIG. 3 is used. According to the graph display unit 17, for example, 17a indicates the in-focus position,
By making the left end 17b side show the front focus state (that is, the state where the subject is in front of the subject) and the right end 17c side show the rear focus state (that is, the state that the subject is behind the subject). The photographer can accurately know which of the left and right directions the manual focus mechanism 2 should be finely adjusted based on the lighting position of the graph display unit 17, and can perform quicker and more accurate focusing. Becomes Further, the graph display section shown in FIGS. 2 and 3 is not limited to the case where the graph display section is combined with the image signal and displayed in the electronic viewfinder, and electroluminescence, LED, liquid crystal display (LCD), etc. It may be formed in and around the electronic viewfinder. Further, although the electronic still camera having the manual focus function is shown in the present embodiment, the present invention is not limited to this, and the present invention is not limited to this, and the present invention is applicable to any type having an auto focus function as long as it can be switched to the manual focus. Applicable. Besides, the present invention is not limited to the electronic viewfinder of the electronic still camera, and the present invention can be applied to the optical viewfinder of the electronic still camera or the silver salt camera.

[0018]

As described above, according to the camera apparatus of the present invention, the focus status display means is configured to display the transition status of the focus status detected by the focus status detection means. Therefore, if the focusing condition display means is provided in the viewfinder, the image in the viewfinder can be checked with the naked eye, and at the same time, the focusing condition can be checked by the graph display showing the transition state of the focusing state. Since this is possible, there is an excellent effect that focusing can be performed quickly and surely even by manual operation.

[Brief description of drawings]

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

FIG. 2 is a schematic diagram showing a graph display unit that constitutes a focus state display means of the electronic still camera according to the embodiment of the present invention.

FIG. 3 is a schematic view showing another graph display unit that constitutes a focus state display means of the electronic still camera according to the embodiment of the present invention.

[Explanation of symbols]

 1 Lens System (Imaging Optical System) 2 Manual Focus Mechanism 3 Imaging Device (CCD (Charge Coupled Device)) 4 Amplifier (Op Amp) 5 A / D Converter 6 Image Signal Processing Circuit 7 High Pass Filter (HPF) 8 Integrator (Focusing) State detection means) 9 CPU (Central Processing Unit) 10 Operation switch 11 Image memory 12 Recording device 13 D / A converter 14 Encoder 15 Electronic viewfinder 16 Graph display section (bar graph) 17 (17a, 17b, 17c) Graph display Department

Claims (1)

[Claims] 1. A light receiving means for photoelectrically converting a subject light image incident through an image pickup optical system, a focus state detecting means for detecting a focus state based on an output signal from the light receiving means, and the focus. A camera apparatus comprising: a focus state display unit that displays a transition state of the focus state detected by the state detection unit.