JPH08256290A - Image pickup device - Google Patents

Abstract

PURPOSE: To correct an exposure of an object optimizingly with a simple operation by selecting a video image area intended by a photographer, detecting an exposure state of the video area corresponding to position information with emphasis and storing the corrected exposure. CONSTITUTION: A 2-dimension position selection means 21 selects a signal corresponding to a prescribed part of a screen from a video signal outputted from an image pickup element 3, and a photometry control means 20 and an AE detection circuit 17 detect an exposure state of a video image area corresponding to a position selected by the 2-dimension position selection means 21 with emphasis. Then an automatic exposure control section 18e, an AGC control section 18a, an electronic shutter control section 18b and an iris control section 18c control the exposure state in response to the detection signal and when an exposure state discrimination section 18f discriminates an optimum exposure state, a data hold section 18d stores control variables to keep the exposure state. Thus, a video image intended by a photographer is obtained with a simple operation regardless of performance of a monitor means such as an electronic view finder or the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to exposure control of an image pickup device.

[0002]

2. Description of the Related Art In recent years, video equipment such as a video camera has been remarkably advanced, and its multifunction and high performance have been improved. In particular, in order to always perform optimal shooting in any shooting situation. The exposure control is extremely important for the camera.

FIG. 4 is a block diagram showing the configuration of an example of an image pickup apparatus such as a video camera prior to the present application.

The structure of the image pickup apparatus in the figure is as follows: 1 is an image forming lens group for an object, and 2 is a diaphragm mechanism such as an iris of a diaphragm blade structure for controlling the amount of incident light or liquid crystal means for controlling the amount of transmitted light. Shows the case of using.

Reference numeral 3 is an image pickup device such as a CCD for photoelectrically converting incident light, 4 is a diaphragm detecting means using a hall element for detecting the state of the diaphragm mechanism, and 5 is an IG meter for driving the diaphragm mechanism. Drive motor, 6 is the image pickup device 3
And read out the photoelectrically converted image pickup signal,
An image sensor control circuit for controlling a so-called electronic shutter function for controlling a signal storage time, 7 is a sample hold circuit for sampling a signal photoelectrically converted by the image sensor 3, and 8 is an image signal output from the sample hold circuit 7. Is an automatic gain control circuit (hereinafter, referred to as an AGC circuit) having a variable gain for electrically amplifying.

Reference numeral 9 is a camera signal processing circuit for generating a standard TV signal by adding a synchronizing signal after processing such as gamma correction, color separation, and color difference matrix, and is a camera signal processing circuit for processing in an analog signal state. is there.

Reference numeral 10 is a video tape recorder (hereinafter referred to as VTR) for recording a video signal on a tape, 11 is an electronic viewfinder (hereinafter referred to as EVF) for monitoring an image being photographed, and 12 is the AGC circuit 8. An AE detection circuit for detecting the exposure state of the subject from the output video signal, and an integration circuit for integrating the luminance level of the video signal in a predetermined period.

Reference numeral 13 denotes a shutter speed of an electronic shutter controlled by the diaphragm mechanism 2 and the image pickup device control circuit 6, based on the detection signal of the AE detection circuit 12, and the AGC circuit 8.
Is an exposure control circuit for controlling the gain and the like of the.

Reference numeral 14 is an iris drive circuit for moving a motor for driving the diaphragm mechanism 2 in accordance with the output of the exposure control circuit 13, reference numeral 15 is an exposure setting key for setting exposure during manual exposure control, and 16 is an exposure control method. Exposure control auto / manual selection key to select.

The internal configuration of the exposure control circuit 13 is such that the average brightness level output from the AE detection circuit 12 is an automatic exposure control circuit 13d for performing automatic iris control.
To the AGC control unit 1 so that the luminance level of the video signal becomes constant at a predetermined value.
3a, an electronic shutter control section 13b and an iris control section 13c for varying the storage time of the image pickup device, respectively, to control the operating states of the AGC, electronic shutter and iris, respectively.

Reference numeral 13e is a manual exposure control circuit for controlling the manual iris, and the exposure setting key 15
Operation, the iris aperture value is read from the look-up table 13h by operating the exposure setting key 15,
It is supplied to the comparison circuit 13g, is compared with the aperture value information from the iris encoder 4, and is configured to output information according to the difference between the operation value of the exposure setting key 15 and the aperture value from the iris encoder 4. .

The iris control information output from the comparison circuit 13g is supplied to the iris drive section 13c after being subjected to predetermined exposure correction or aperture characteristic correction by the correction calculation circuit 13f, and then iris drive. Motor 6
Drive iris 2 via.

As a result, the iris 2 is driven so that the inputs of the comparison circuit 13g become equal to each other, that is, until the aperture value becomes equal to the aperture value set by the exposure setting key 15, which depends on the manual operation. Iris control is possible.

Further, the A / MSW selects the automatic exposure control circuit 13d by the exposure control auto / manual selection key 16 when it is switched to the A contact side, and the manual exposure control circuit 13e when it is switched to the M contact side. Is a switch for selecting.

According to the image pickup apparatus having the above-mentioned structure, in order to enable the optimum image to be obtained by simple photographing in various places and under various conditions, the AE detection circuit 12 changes the subject from the image signal. The exposure control parameters such as the gain of the AGC circuit 8 and the electronic shutter for controlling the accumulation time of the diaphragm mechanism 2 and the image pickup device 3 are detected by the exposure control circuit 13 based on the detection signal of the AE detection circuit 12 And the correction amount of each parameter are determined, and control is performed so that stable and optimum exposure is always obtained.

Thus, without bothering the photographer's hand,
It is possible to automatically perform optimum exposure control. Further, in the AE detection circuit 12, by controlling the photometric distribution by setting the detection area and the detection position of the video signal for exposure control, more optimal photography is possible.

For example, so-called average photometry in which the entire image area is detected and exposure control is performed so that the detection signal has a constant level, or only the central portion of the image area is detected, and the detection signal has a constant level. It is possible to implement a center-weighted metering method with exposure control.

Further, in the AE detection circuit, the detection data of the entire image area and the detection data of the central emphasis area are respectively weighted, and exposure control is performed based on the detection data obtained by adding each data at a constant ratio. With this, exposure control can be performed by photometry that combines average photometry and center-weighted photometry, and it compensates for the shortcomings of each photometry method and provides more optimal exposure.

Further, finer exposure control can be performed by subdividing the screen to detect the image of each area and limiting the area of the detection data used for the exposure control or changing the weighting.

However, even in the above-described photometric method, the exposure-controlled state is not always the exposure state intended by the photographer.

For example, in the case of shooting a backlit person, the exposure state of the person is darkened by what is affected by the bright part of the background, that is, it becomes a so-called black shadow, or when the person is illuminated by a spotlight, the light is over-exposure. In such a case, on the contrary, the exposure state of the person becomes too bright, or so-called overexposure occurs.

In order to deal with such a photographing situation, conventionally, a manual exposure correcting means has been devised in which a photographer manually sets an exposure state. A so-called manual iris means for holding the diaphragm state set by the photographer regardless of the state of the diaphragm mechanism 2 which is one means of the manual exposure correcting means and the detection signal of the AE detection circuit 12 will be described.

The photographer selects automatic / manual exposure control method with the exposure control auto / manual selection key 16.
When the manual exposure control method is selected, the control means inside the exposure control circuit 13 is switched to the manual exposure control section.

The manual exposure control section is provided with a look-up table (LUT) and a comparing means for comparing the LUT data with the detection signal of the iris encoder 4 for detecting the aperture of the iris. As described above, a typical aperture state represented by the F value from the open state to the closed state of the iris is set, and the value of the iris encoder 4 corresponding to each aperture state is set.

The exposure setting key 15 allows the photographer to monitor the screen of the EVF 11 while selecting the brightness of the subject to be the intended brightness, whereby the data to be read by the LUT is selected in accordance with the setting signal of the exposure setting key 15. , And the output signal of the iris encoder 4 are compared by a comparison means.

If there is a difference as a result of the comparison by the comparing means, a correction amount is calculated, and the iris is controlled so that the value of the iris encoder 4 becomes equal to the data read out from the look-up table.

This makes it possible to correct the exposure state of the subject to the brightness intended by the photographer. At this time, A
The control values for the GC and electronic shutter are set to the fixed values set in advance in the LUT, or fixed to the control values when the exposure control method is switched from auto to manual. If you select a setting value, you can make detailed exposure settings according to the shooting conditions.

[0028]

However, not only the above-mentioned manual iris means but also the manual exposure control means need to perform exposure correction while confirming the exposure state with the monitor means such as EVF11. A certain EVF 11 is generally small in size so that it can be seen with one eye, so the screen size is small, and due to the fact that the EVF using liquid crystal means does not have a sufficient dynamic range due to colorization. Since it is difficult to confirm the accurate exposure state of the subject, it is difficult to set the optimum exposure, and the exposure state intended by the photographer may deviate from the actually set exposure state.

Since a more complicated key input operation is required, a certain amount of photography experience is required, and there is a problem that a photographer with little photography experience cannot use it.

Therefore, an object of the present invention is to provide an image pickup apparatus capable of optimally correcting the exposure state of a subject aimed by a photographer by a simple operation regardless of the performance of a monitor means such as an EVF. is there.

[0031]

In order to solve the above-mentioned problems, according to the invention described in claim 1 of the present application, an image pickup means (corresponding to the image pickup element 3 in the embodiment) and the image pickup means are provided. Corresponding to the position selection means (corresponding to the two-dimensional position selection means 21 in the embodiment) for selecting a signal corresponding to a predetermined portion in the screen from the output video signals, and the position selected by the position selection means. Detection means (in the embodiment, the photometric area control means 2) that focuses on detecting the exposed state of the image area.
0, which corresponds to the AE detection circuit 17) and an exposure control unit (in the embodiment, an automatic exposure control unit 18e and an AGC control unit 18) that controls the exposure state according to the detection signal of the detection unit.
a, electronic shutter control unit 18b, iris control unit 18
(corresponding to c), an exposure state determination unit (corresponding to the exposure state determination unit 18f in the embodiment) for determining whether or not the exposure state has been optimized, and a control value of the exposure control unit. Exposure state holding means for holding the exposure state (corresponding to the data hold unit 18d in the embodiment),
Causing the exposure control means to perform exposure control so that the exposure state of the region corresponding to the position selected by the position selection means becomes optimum based on the detection signal detected by the detection means,
When the exposure state determination means determines that the exposure state is optimized, the exposure state holding means holds the exposure state at that time (in the embodiment, the exposure correction execution key 2).
2, the switch SW1 corresponds to the switch SW2).

According to the invention of claim 2 of the present application, the photographer on the screen of the electronic viewfinder is gazing as the position selecting means (corresponding to the two-dimensional position selecting means 21 in the embodiment). A structure using two-dimensional position selecting means such as a gazing point position detecting means for detecting position information, a joystick, a track ball, a mouse, a touch panel, etc. is used.

[0033]

According to the invention described in claim 1 of the present application, the photometric area can be moved to a subject at an arbitrary position on the screen, and after the exposure state is optimally corrected for the subject,
The exposure control state can be maintained.

According to the second aspect of the present invention, the exposure state at any position on the screen can be determined by using the two-dimensional position selecting means such as the gazing point position detecting means, the joystick, the track ball, the mouse and the touch panel. Can be optimized.

[0035]

【Example】

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

FIG. 1 is a block diagram showing the configuration of the first embodiment of the present invention. The parts denoted by the same reference numerals as those of the preceding example shown in FIG. 4 have the same functions, and the description thereof will be omitted.

The difference from the configuration of FIG. 4 is that a (two-dimensional) position selection means 21 for designating an arbitrary position on the screen, a photometric area control means 20, and an exposure correction execution key 22 are newly added. The difference is that the functions of the AE detection circuit 17 and the exposure control circuit 18 are different. The process of processing other video signals is similar.

Normally, as in the prior art example of FIG. 4, the AE detection circuit 17 detects the change in exposure due to the change in the subject from the video signal, and the exposure control circuit 18 detects the change in the AE detection circuit 17.
Aperture mechanism (iris) 2 and image sensor 3 based on the detection signal of
The exposure control parameters such as the electronic shutter and the gain of the AGC circuit 8 for controlling the storage time of the exposure parameters are selected and the correction amount of each parameter is determined, and the control is performed so that the exposure is always stable and optimal.

The internal structure of the exposure control circuit 18 is such that the average luminance level output from the AE detection circuit 17 is an automatic exposure control circuit 18e for performing automatic iris control.
To the AGC control unit 1 so that the luminance level of the video signal becomes constant at a predetermined value.
8a, an electronic shutter control unit 18b and an iris control unit 18c for varying the storage time of the image pickup device, respectively, to control the operating states of the AGC, electronic shutter, and iris, respectively.

However, the automatic exposure control circuit 18e and the AGC
A data hold consisting of an AGC data hold unit 181, an electronic shutter data hold unit 182, and an iris data hold unit 183, which hold control data for the control unit 18a, the electronic shutter control unit 18b, and the iris control unit 18c, respectively. The portion 18d is provided.

Further, in 18f, the switch SW1 to be described later becomes O.
Only in the N state, the switch SW2 is turned on to determine whether or not the proper exposure state has been obtained based on the calculation result of the auto exposure control unit. When the proper exposure state is determined, the data hold unit is in the hold ON state. The exposure state determination unit outputs a control signal.

Therefore, according to the above configuration, in order to enable the optimum image to be obtained by simple photographing in various places and under various conditions, the AE detection circuit 17 detects the object from the image signal. The exposure control circuit 18 detects the change in the exposure, and the exposure control circuit 18 controls the exposure time of the aperture mechanism 2 and the image pickup device 3 based on the detection signal of the AE detection circuit 17 and the electronic shutter for controlling the storage time of the image sensor 3. The parameters are selected and the amount of correction for each parameter is determined, and control is performed so that stable and optimum exposure is always achieved.

On the other hand, the (two-dimensional) position selecting means 21
A line-of-sight detection device that detects the gazing point on the screen while looking at the VF screen, a Joystick, a trackball, a mouse,
It is applicable as long as the horizontal position and the vertical position can be designated within a two-dimensional plane such as a touch panel. The designated position selected by the (two-dimensional) position selecting means 21 is supplied to the display circuit 19 and a predetermined index (for example, frame display, cursor display, etc.) is superimposed on the screen of the EVE 11.

Reference numeral 20 is a photometric area control means (circuit) for setting a photometric area at a position on the screen designated by the (two-dimensional) position selection means 21, and is a gate circuit of the AE detection circuit 17. By turning ON / OFF,
It is controlled so that only the output in the AE detection circuit 17 corresponding to the position designated by the (two-dimensional) position selection means 21 is passed.

Reference numeral 22 denotes an exposure correction execution key, which is set to O
A switch SW1 provided between the AE detection circuit 17 and the photometric area control circuit 20 and a switch SW2 provided between the automatic exposure control section 18e and the exposure state determination section 18f are turned on / off by turning it on / off. Is.

When the exposure correction execution key is in the OFF state, the switch SW1 is in the OFF state, the AE detection circuit 17 is disconnected from the photometry area control means 20, outputs the photometry information of the fixed photometry area, and switches the switch. Since SW2 is also turned off, the exposure state determination unit 18f is separated from the automatic exposure control unit 18e, and the data hold unit 18
A hold-OFF signal is also output as an output signal for controlling d, and similarly to the normal auto-exposure control operation described with reference to FIG. 4, the exposure control parameters are corrected in accordance with changes in the video signal, and are always Stable and optimal exposure control is automatically performed.

Next, details of the manual exposure correction means, which is a feature of the present invention, will be described.

In the present invention, the (two-dimensional) position selecting means 21 capable of selecting at least a part of the part included in the video signal.
The display circuit 19 for displaying the image position selected by the two-dimensional position selecting means 21 on the screen of the EVF 11 which is the monitor means as shown in FIG. 7 is as described above.

The (two-dimensional) position selecting means 21 uses input means such as a joystick, a trackball, a mouse, and a touch panel, or a position of a gazing point for detecting the position information of the photographer on the screen of the EVF 11. For example, there is a configuration in which the viewpoint of the photographer is used as the input means by using the means.

Further, as shown in FIG. 7, the center position of the object to be selected can be selected, or a predetermined image area can be displayed in a fixed frame as shown in FIG. 7, and the target object can be put in the fixed frame. In addition to selectively setting the position of the fixed frame as described above, not only the position of the target subject as shown in FIG. 7 but also the video area may be freely selected according to the size of the subject. .

Here, as shown in FIG. 7, a description will be given focusing on a case where a predesignated image area is displayed in a fixed frame and the position of the fixed frame is selectively set so that a target object is included in the fixed frame. To go.

In the above-described structure, if the target subject is not optimally exposed by the automatic exposure control, such as blackout due to backlighting or overexposure due to over-exposure, the photographer may use the above (2)
The (dimensional) position selecting means 21 sets the fixed frame position to the position of the subject to be optimally exposed.

The position signal of the (two-dimensional) position selection means is input to the photometric area control means 20 to detect the exposure state of the image area corresponding to the fixed frame position selected by the (two-dimensional) position selection means. Controls the photometric area.

The photometric area control is not limited to the position of the object as shown in FIG.
When the image area can be freely selected according to the size of the subject, not only the photometric area position is controlled corresponding to the position selected by the (two-dimensional) position selecting means, but also the selected image is selected. The photometric area is also controlled corresponding to the area.

However, at this stage, the switch SW2 becomes O.
In the FF state, the output signal from the photometric area control means 20 is A
It is not input to the E detection circuit 17. The switch SW2
Is controlled by the output signal of the exposure correction execution key 22, and the exposure correction execution key 22 performs the exposure correction operation after the fixed frame position setting for the subject position to be subjected to the exposure correction by the two-dimensional position selection means 21 is completed. This is one of the input means by which the photographer inputs a trigger signal when he / she wants to start it. When the trigger signal is input by the exposure correction execution key 22, the switch 2 is turned on. When the switch 2 is turned on, the exposure state of the image area corresponding to the photometric area set by the photometric area control means 20 is detected by the AE detection circuit 17.

The automatic exposure control section 18 of the exposure control circuit 18
At e, an electronic shutter for controlling the accumulation time of the diaphragm mechanism 2 and the image pickup device 3 according to the detection signal in the photometric area set by the (two-dimensional) position selection means of the AE detection circuit 17, and the AGC circuit 8. The exposure control parameter such as gain is selected and the correction amount of each parameter is determined, and the control value is calculated so as to obtain stable and optimal exposure.

On the other hand, the trigger signal of the exposure correction execution key 22 turns on the switch SW1 of the exposure control circuit 18, and the calculation result of the automatic exposure control section 18e is input to the exposure state determination section 18f.

The exposure state determination unit 18f is a switch SW.
Only when 1 is in the ON state, it is determined whether or not the proper exposure state is obtained based on the calculation result of the automatic exposure control unit 18e,
The data hold unit 18 when it is determined that the exposure state is appropriate.
The control signal that outputs the hold ON state is output.

When the switch SW1 is in the OFF state, or when the result of the exposure state determination section determines that the exposure state is not appropriate, the control signal for outputting the state of the data hold section 18d to the hold OFF state is output.

In the data hold unit 18d, the automatic exposure control unit 18e is responsive to the control signal from the exposure state determination unit.
Iris control value, electronic shutter control value, A
It controls the selection of the exposure control parameter such as the GC control value and whether to hold the correction value of each parameter.

When in the hold-off state (SW2 is OFF), the iris control values selected by the auto exposure control unit, the electronic shutter control value, the AGC control value, and other exposure control parameters are selected, and the correction values for each parameter are controlled by the iris control. Section, the electronic shutter control section, and the AGC control section as they are, and the correction operation is performed by following changes in the video signal.

In the hold ON state (SW2 is ON), the iris control value, electronic shutter control value, AG
Selection of exposure control parameters such as C control values and correction values of each parameter are stored, and the stored values are respectively stored in the iris control unit, the electronic shutter control unit, and the AGC control unit regardless of changes in the brightness of the subject. Output.

Here, when the iris data hold unit uses a diaphragm blade driven by a stepping motor as the diaphragm mechanism 2 or a means for controlling the amount of transmitted light by a liquid crystal means or the like, it is sufficient to hold the control data. When a means such as a diaphragm blade using is used, it is necessary to detect the state of the iris and perform feedback back control. In such a configuration, the configuration shown in FIG. 5 is used.

That is, there is no data hold 183,
Comparison circuit 1 compares the exposure control data output from data hold circuit 183c with the aperture value from the iris encoder.
83b, and a signal corresponding to the difference is compared with the correction arithmetic circuit 1
It outputs to the iris control unit via 83a. That is, the aperture mechanism 2 is controlled so that the exposure control data output from the data hold circuit 183c and the iris encoder become equal.

In this way, when the trigger signal is input from the exposure correction execution key 22, the two-dimensional position selecting means 2
The correction operation is started so that the exposure state of the image area selected in step 1, that is, the photometry area is optimized, and the correction operation is continued until the exposure state determination unit determines that the exposure state is optimized.

When it is determined that the optimum exposure is achieved, the correction operation is terminated and the data hold unit is controlled to the hold ON state to maintain the optimum exposure control state. As a result, the zoom magnification fluctuates, and even if the surrounding brightness changes, the exposure state of the subject selected by the two-dimensional position selecting means 21 is maintained as it is.

As described above, according to the present invention, when the photographer inputs a trigger signal at a timing when he / she wants to select an image area of a subject to be optimally exposed and to perform exposure correction, the brightness state of the selected image area is detected. , A series of correction operation operations in which the exposure correction operation is performed while determining whether or not the exposure status has been optimized, and the exposure status is maintained when the exposure status of the selected image area is corrected to the optimum status. Automatically.

(Second Embodiment) FIG. 2 is a block diagram showing the configuration of the second embodiment of the present invention.

The second embodiment shows a case where a camera signal processing circuit 9'for performing digital signal processing is used as the camera signal processing circuit of the first embodiment. After the video signal is A / D changed, a predetermined process is performed, D / A conversion is performed, and then output.

The difference from the first embodiment is that the exposure control circuit is composed of a micro computer 23, and the AE detection circuit 17 and the photometric area control means 21 of the first embodiment are provided in the micro computer 23. 23 g and the photometric area control means 23 h are incorporated into the micro computer 2 for performing the respective processes performed in the first embodiment.
It is possible to do it in the digital signal state within 3.
It can be realized with a simple configuration.

The other circuit functions of 23a to 23f are the same as the circuit functions of 18a to 18f in FIG. 1 of the first embodiment, and the exposure correction method itself is the same as that of the first embodiment.

(Third Embodiment) In the first and second embodiments, the AGC circuit 8 and the electronic shutter function for controlling the accumulation time of the diaphragm mechanism 2 and the image pickup device 3 as the exposure control parameters at the time of executing the exposure correction of the present invention. The example of holding the value of each control parameter when the optimum exposure condition is reached by selecting the optimum control parameter for exposure correction and determining the correction amount of each control parameter is described above. It is not always necessary to use the above three control parameters, and one or two control parameters can be used in combination.

In the third embodiment, the case where only the diaphragm mechanism 2 is used as the exposure control parameter used when the exposure correction of the present invention is executed will be described.

The operation of the third embodiment differs from that of the first embodiment in that when a trigger signal is input from the exposure correction execution key 22, the control values of the electronic shutter and AGC control parameters are the exposure correction execution key 22. The exposure correction operation is performed by fixing the data at the moment when the trigger signal is input or the preset data and optimizing the exposure state of the image area selected by the two-dimensional position selecting means 21 only by the diaphragm mechanism 2. Is the point to do.

When the exposure state determination unit determines that the exposure state has been optimized, the correction operation by the iris is ended and the data hold unit is controlled to the hold ON state,
Hold only the iris data.

As a result, the configuration and processing can be simplified.

(Fourth Embodiment) FIG. 3 is a block diagram showing the configuration of the fourth embodiment of the present invention. In the figure, the difference from the first embodiment of FIG. 1 is the configuration of the exposure control circuit 24.

Circuit configurations 24a-2 in the exposure control circuit 24
4c corresponds to the circuit configuration of 18a to 18c of FIG. 1, and the circuit configurations of 18d, 18e, and 18f of FIG. 1 correspond to 24f, 24g, and 24h of FIG. 3, respectively.

The exposure control circuit 24 including in the fourth embodiment is different from the exposure control circuit 18 in the first embodiment in that the data hold unit 24f and the iris control unit 24c are provided.
The LUT 24 as shown in FIG. 6 in which the LUT data conversion section 24d and the data of each exposure control parameter are stored between the AGC control section 24a and the electronic shutter control section 24b.
e.

By adding the exposure setting key 25,
As in the first embodiment, the exposure state of the selected image area can be automatically and optimally corrected and can be reset from the held state by the exposure setting key 25 like the conventional manual iris.

Here, the case of the structure of the first embodiment is taken up as the basic structure, but the same can be applied to the structures of the second and third embodiments.

[0082]

As described above, according to the invention described in claim 1 of the present application, the two-dimensional position selecting means is provided with the two-dimensional position selecting means capable of selecting the image area intended by the photographer. Monitors such as electronic viewfinders by focusing on the exposure state of the video area corresponding to the position information, performing exposure compensation based on the detection signal, and maintaining the exposure state when the optimal exposure state is reached. There is no need to perform exposure compensation while checking the exposure state on the screen of the means, and regardless of the performance of the monitor means, the exposure state of the main subject aimed by the photographer can be optimally corrected with a simple operation,
Even if the exposure state of the surrounding subject changes due to the change of the zoom magnification or the movement of the main subject, the exposure state of the main subject can be maintained as it is, and it is possible to provide the image as the photographer intended. can get.

According to the second aspect of the present invention, the two-dimensional position selecting means can be selected using the line-of-sight input, the joystick, the trackball, the mouse, the touch panel, etc., so that the photographer can perform a simpler operation. It is possible to optimally correct the exposure state of the aimed main subject, and it is possible to provide the effect that the image as intended by the photographer can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a second exemplary embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a fourth exemplary embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a conventional example.

FIG. 5 is a block diagram showing a configuration of iris data hold means.

FIG. 6 is a diagram showing an example of a look-up table.

FIG. 7 is a diagram showing a display of a selected position and an area for photometry.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Object imaging lens group 2 Aperture mechanism (iris) 3 Imaging device 4 Aperture mechanism state detection means 5 Aperture mechanism drive motor 6 Imaging device control circuit 7 Sample hold circuit 8 Auto gain control circuit 9 Camera signal processing circuit 10 Video tape recorder 11 Electronic View Finder for Monitor 12 AE Detection Circuit of Conventional Example 13 Exposure Control Circuit of Conventional Example 14 Iris Drive Circuit 15 Exposure Setting Key 16 Exposure Control Auto / Manual Selection Key 17 AE Detection Circuit of First and Fourth Embodiments 18 Exposure control circuit 19 of the first embodiment 19 Display circuit 20 Photometric area control means 21 Two-dimensional position selection means 22 Exposure correction execution key 23 Microcomputer 24 Exposure control circuit 25 of the fourth embodiment 25 Exposure setting key

Claims (2)

[Claims] 1. An image pickup device means, a position selection means for selecting a signal corresponding to a predetermined portion in a screen from among the video signals output from the image pickup means, and a position selected by the position selection means. Detection means for focusing on the exposure state of the image area, exposure control means for controlling the exposure state according to the detection signal of the detection means, and exposure for determining whether or not the exposure state is optimal. A state determination unit, an exposure state holding unit that stores the control value of the exposure control unit and holds the exposure state, and a position selected by the position selection unit based on a detection signal detected by the detection unit. Causing the exposure control means to perform exposure control so that the exposure state of the corresponding region is optimal,
An image pickup apparatus comprising: a control unit that causes the exposure state holding unit to hold the exposure state at that time when the exposure state determination unit determines that the exposure state is optimum. 2. The position selecting means according to claim 1, such as a gazing point position detecting means for detecting position information of the photographer on the screen of the electronic viewfinder, a joystick, a trackball, a mouse, a touch panel, etc. An image pickup device using a two-dimensional position selecting means.