JPS61123368A - Camera - Google Patents

Abstract

PURPOSE:To enable to perform the stabilized adjustment of exposure as well as allowing to measure proper exposure regarding the subject as a target by establishing the means of movement of focus detection means, automatic exposure adjustment means and exposure measuring range of view in interlocking with focus detection range of view. CONSTITUTION:When focus detection range of view site information is transferred from focus detection range of view setting equipment 12 to AE gate signal generating circuit 11, the circuit 11 generates AE gate signal, and timing of the signal is controlled by the site information. Thus, the exposure measuring range of view moves in interlocking with the focus detection range of view. Gate signal corresponding to the focus detection range of view established by the equipment 12 is provided to AE gate circuit 13. Signal of luminiferous degree is provided to the automatic focus detection circuit 14 through circuit 13, the focus detection is performed, and automatic adjustment of focus is made. Therefore, the stabilized adjustment of exposure is possible as well as allowing to make proper exposure measurement of the subject as a target by setting the means 12, 9 and 11.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a camera, mainly a video camera, equipped with an automatic exposure adjustment means, and in particular a means that can obtain proper exposure and perform stable exposure adjustment. Regarding.

(Prior Art) Conventionally, an automatic exposure adjustment device for a video camera is shown in Fig. 14 (
As shown in EF in A), the luminance signal in the video signal corresponding to a certain area within the shooting screen (hereinafter referred to as exposure measurement field of view) is integrated, and the exposure is adjusted by adjusting the aperture, etc. so that the integrated value becomes constant. This was based on a method that controlled the adjustment section.

By the way, it is known that with such an exposure measurement field of view setting means, a difference occurs in the amount of exposure depending on the drawing conditions at the time of photographing. As a metering method for this exposure adjustment, methods such as partial metering, average metering, center-weighted metering, split metering, or spot metering, each with their own unique weighting, have been proposed, but the influence of the background light source It had its pros and cons, such as being susceptible to exposure to light, and the exposure adjustment being unstable when it came to moving subjects.

FIG. 15 shows the main parts of an example of a video camera equipped with a conventional automatic exposure adjustment device, in which 1 is a focusing lens, 2 is a zoom lens, 3 is an aperture, and 4 is a relay lens. , 5 are C, C, and D as imaging means, which receive the light flux from the subject, are driven by the image sensor driving circuit 6, and output a time-series signal, and this signal is sent to the signal processing circuit 7.
The video signal is subjected to modulation and correction processing, and is combined with a synchronization signal to form an output video signal (for example, an NTSC signal), which is then supplied to a user device. Reference numeral 8 denotes a gate circuit (hereinafter referred to as AE gate circuit) for setting an exposure measurement field of view for exposure adjustment, and is composed of an analog multiplier and the like. 9 is an automatic exposure adjustment circuit including an integrator, and 10 is an aperture drive device, which is often configured together with the aperture 3 as an iris meter.

11' is a gate signal generation circuit (hereinafter referred to as AE gate signal generation circuit) for generating a gate signal for the AE gate circuit 8, and the waveform of the generated gate signal (hereinafter referred to as AE gate signal) is based on the photometry method. In average photometry, a portion of the entire screen is measured, and in spot photometry, a rectangular pulse that opens the gate only at and around the center of the screen is output. Furthermore, in a method having characteristics intermediate between average photometry and partial photometry, such as center-weighted photometry, a trapezoidal or chevron-shaped waveform is output instead of a rectangular one.

In the above configuration, the luminance signal component in the video signal output from the signal processing circuit 7 is supplied to the automatic exposure adjustment circuit 9 via the AE gate circuit 8, added to the integrator in the circuit 9, and integrated. be done. And the aperture drive device lO,
When the above-mentioned integral value is larger than a predetermined threshold value, the aperture is set to 3.
On the other hand, when it is smaller than a predetermined threshold value, the diaphragm 3 is driven in the direction of opening, and as a result, closed-loop automatic control is performed so that the integral value is maintained at a predetermined value.

According to the above-mentioned conventional technology, whether or not an exposure amount matching the photographer's intention can be obtained largely depends on the photometry method. In other words, average photometry, which is said to be for general use, is
Exposure can be adjusted to a certain extent for most shooting conditions, but in cases such as backlighting, the exposure will be significantly under-represented for the target subject.On the other hand, partial metering is preferred by people with relatively advanced photography skills. can provide appropriate exposure for the target subject, but if the subject moves and often deviates from the exposure measurement field of view as shown in Figure 14 CB), exposure adjustment becomes unstable. Methods such as center-weighted metering and split metering have been proposed in order to alleviate the drawbacks of the above two methods, but the reality is that even these methods end up only providing intermediate characteristics. It is.

(Purpose) The present invention reduces or eliminates the above-mentioned drawbacks of cameras equipped with conventional automatic exposure adjustment devices, and enables proper exposure for a target subject, such as partial metering or spot metering, and average exposure adjustment. It is an object of the present invention to provide a camera equipped with automatic exposure adjustment means capable of performing stable exposure adjustment such as δI4 light or split metering.

(Explanation based on Examples) Hereinafter, the means taken in this invention to achieve the above object will be exemplified and explained with reference to the examples shown in FIGS. 1 to 13 and the like. The following description will be made in the order of the overall configuration of an embodiment of the camera of the present invention, and a modified embodiment of the present invention in which the embodiment includes focus detection field of view setting means and automatic tracking focus detection means.

(Overall Configuration of an Embodiment of the Camera of the Invention) (FIG. 1) FIG. 1 shows the overall configuration of an embodiment of the camera of the invention. 10 has basically the same configuration and function as the conventional example shown in FIG. 15, so detailed explanation will be omitted. Of the above, the imaging means 5 may be either an imaging tube or a solid-state imaging device such as C, C, or D, but here it is assumed that it is C, C, or D. The image sensor drive circuit 6 that drives C, C, and D is driven by a signal obtained by frequency-dividing a clock pulse generated by a clock pulse generation circuit (not shown), and the above-mentioned synchronization signal is based on this frequency-divided signal. The signal is generated by a synchronization signal generation circuit (not shown), and since these are also well-known means, a detailed explanation will be omitted.

The automatic exposure adjustment function itself in the device shown in FIG.
Similar to the conventional example shown in the figure, the luminance signal component in the output video signal is integrated by an integrator in the automatic exposure adjustment circuit 9, and this integrated value is set to a predetermined desirable value (XI adjustable). The system performs closed-loop automatic control to close or open the diaphragm 3 depending on its size.

The feature of the device shown in FIG. 1 is that the focus detection field of view position information is transferred from the focus detection field of view setting device 12 to the AE gate signal generation circuit 11, and the timing of the AE gate signal generated by the circuit 11 is controlled by this position information. , the exposure measurement field of view is moved in conjunction with the focus detection field of view.

The AE gate signal generation circuit 11 is similar to the AE gate signal generation circuit 11' in FIG. 15 in that it generates an AE gate signal.
The difference is that the timing of the generated AE gate signal is controlled by the position information from the focus detection field setting device 12.

To set the position of the focus detection visual field in the focus detection visual field setting device 12, (1) move the focus detection visual field position by operating a knob, etc., (2) move the focus detection visual field position among the plurality of preset focus detection visual field divisions. Select any category, (
3) It is possible to track a moving subject and move the position of the focus detection field of view.

On the other hand, in order to generate an AE gate signal that sets a corresponding exposure measurement field of view according to position information from the focus detection field of view setting device 12, the AE gate signal is generated based on an analog signal or a digital signal generated by the device 12. All you have to do is control the timing. Here, an example in which processing is performed based on a digital signal will be described.The AE gate signal generation circuit 11 includes a programmable counter, and this counter is programmed using the above-mentioned digital signal. Then, a required AE gate signal may be generated in synchronization with a pulse generated when the programmed value is counted.

Generally, the waveform of the AE gate signal mentioned above may be any waveform conventionally used in automatic exposure adjustment devices.
Partial photometry, spora) Jl light or focused photometry in the center where the focused area is relatively narrow (the center of the focus detection field of view) is desirable.
These methods can exhibit the characteristics of each method at or near the center of the focus detection field of view.

A gate signal corresponding to the focus detection field of view set by the focus detection field of view setting device 12 is supplied to the AF gate circuit 13, and a luminance signal, for example, in the output video signal is supplied to the automatic focus detection circuit 14 via the AF gate circuit 13. Here, for example, the well-known mountain-climbing servo system (for example, rNHK Technical Research J Vol. 17, No. 1 (volume No. 86), published in 1965, p. 21, Haka Ishida, "Automatic focusing of television cameras using mountain-climbing servo system") Focus detection is performed by the AF motor drive unit 15 as is known in the art.
The device 15 drives the AF motor M,
The position of the focusing lens 1 is controlled to perform automatic focusing 7A.

Although the focus detection field described above is not an essential requirement for this invention, it can be displayed on a finder screen etc. in practice, whereas the exposure measurement field is a means for extracting signals for automatic exposure adjustment. Because of this, it is not normally displayed on the finder screen.

(Focus detection field of view setting means in the embodiment of this invention) (
(Fig. 2 to Fig. 10) As means for embodying the focus detection field of view positioning device 212 of Fig. 1, there are two ways to implement the focus detection field of view positioning device 212 of Fig. It is possible to automatically move the The first method for tI users is to move the focus detection field of view using a knob or the like,
In this case, in order to generate the required AE gate signal, the focus detection field of view setting signal generated by operating a knob or the like in the focus detection field of view setting device 12 is transferred to the AE gate setting circuit 11. It is only necessary to control the timing of the AE gate signal.

The second mode of manual setting is to select a plurality of preset focus detection visual field sections, an example of which is shown in FIGS. 2 and 3. In FIG. 2, FR indicates the entire photographic screen, (A) indicates a division corresponding to the focus detection field of view fixed at the center in a conventional focus adjustment device,
It is assumed that, including category (A), a total of 9 categories (B) to (S) are set, including 3 categories both vertically and horizontally.

FIG. 3 shows an example of a focus detection visual field setting device for selecting an arbitrary segment from the focus detection visual field segments shown in FIG. 2, and this example also includes means for displaying the focus detection visual field on an electronic viewfinder. In FIG. 3, 20 is an image pickup means (, C, D, 21 is an image pickup element drive circuit, corresponding to 5 and 6 in FIG. 1, respectively. 22 is a clock pulse generation circuit, and 23 is a A frequency divider that receives clock pulses from the clock pulse generation circuit 22 and divides the frequency.
The required frequency-divided signals are C, C, and D.

20 as well as a synchronization signal generation circuit 24 and a character generator 29, which will be described later. 24 is a synchronizing signal generation circuit, and 25 is a signal processing circuit C, C, D. 2
0 output signal is subjected to necessary modulation and correction processing to output a video signal, and this video signal is combined with a synchronization signal by an encoder 26 to form an output video signal (for example, an NTSC signal).

Reference numeral 27 denotes a joystick as a focus detection field selection means, but any other joystick can be used as long as it can specify the focus detection field divisions; for example, the same number of button switches as the number of focus detection field divisions can be used. Reference numeral 28 is a microcomputer, which receives a signal from the joystick 27 to select, for example, the focus detection field of view section (b), and receives an analog switch 32 (the AF gate circuit in FIG. 1). (equivalent to 13)
It generates a gate signal for the AE gate signal and transfers it to the switch as well as to the AE gate signal generation circuit 11. The AE gate signal generation circuit 11 transfers the AE gate signal to the analog switch 8' (corresponding to the AE gate circuit 8 in FIG. 1) in the same manner as described with reference to FIG. As a result, focus detection is performed using the luminance signal extracted in the focus detection field of view section (b) selected by the joystick 27, and extraction is performed in the exposure measurement field of view that moves in conjunction with the selection of this focus detection field of view section (b). Exposure adjustment is performed based on the brightness signal.

The microcomputer 28 further receives, for example, a signal for selecting the focus detection visual field section (b) described above, and outputs a corresponding focus detection visual field section selection signal to the character generator 29. The character generator 29 receives the frequency division signal from the frequency divider 23 and the focus detection field division selection signal, and outputs an area signal, which is a focus detection field position designation signal, to the signal synthesis circuit 30. 3
0 combines this area signal and the video signal,
transmitting the composite video signal to an electronic viewfinder 31;
The pulse portion of the video signal displays bright lines on both the left and right sides of the focus detection field of view on the finder screen. Note that the shaded area (b) in FIG. 2 emphasizes this bright line area.

34 is a power-on clear circuit, and a clear signal generated when the device is started is input to the microcomputer 28, so that the focus detection field of view is always at the center of the photographing screen as shown in (A) in Fig. 2 at the time of startup. (See Japanese Patent Application No. 82709/1989 filed by the present applicant).

Returning to FIG. 1, the AE gate signal generated by the AE gate signal generation circuit 11 is transmitted to the focus detection field setting device 12 (in FIG. 3, the joystick 27 and the microcomputer 2
8) is controlled by the generated focus detection field of view position information, so the exposure measurement field for automatic exposure adjustment is linked to the focus detection field of view, so that it is possible to determine the correct image for the target subject, such as partial side light or spot in light. In addition to being able to perform exposure, it is also possible to perform stable exposure adjustment such as equal metering or split metering, and the waveform of the gate signal for exposure adjustment itself is a gate signal for setting the focus detection field of view. The waveform can be made suitable for exposure adjustment (photometering) regardless of the signal waveform.

Next, the outline of means for automatically tracking a moving subject and moving the focus detection field of view to follow the movement of the subject will be explained in accordance with the specification of Japanese Patent Application No. 105897/1989 filed by the present applicant. , FIG. 9 and FIG. 10 show specific examples thereof, but prior to the explanation, the principle of the automatic subject tracking function will be explained with reference to FIGS. 4 to 8.

In conventional automatic focus detection or automatic focus adjustment devices, the fourth
As shown in Figure (A), the focus detection field of view is fixed at the center of the shooting screen, so as shown in Figure (B), the target subject below C that you want to focus on (a person in this example) moves. If this happens, an object at a different distance from the target subject (a house in this example) will be in focus, and the target subject, a person, will be out of focus.

On the other hand, in a camera with automatic subject tracking means, the target subject (person) in the state shown in Figure 4 (A)
As shown in Figure 5 (A), when the subject moves to the upper right of the screen while maintaining the same distance, the tracking means described later automatically detects the subject's movement, and the focus detection field of view tracks the subject's movement and moves. (FF in the figure), and focus detection can be performed at that moving position. Further, the exposure measurement field of view (EF) can be moved in conjunction with the focus detection field of view, and exposure adjustment can be performed at the movement position, that is, the movement position of the subject. Note that, as described later, the focus detection field or the tracking field may also serve as the exposure adjustment field.

More specifically, some parameter representing the feature of the subject is extracted with respect to the tracking field of view set by the tracking means, the extracted feature is stored, and the newly extracted feature is combined with the stored feature. The tracking field of view is moved to track the movement of the subject by detecting whether or not the subject is moving, and if the subject moves, the moving direction or moving position based on the characteristics of the subject. With the movement of □, the focus detection field of view and, by extension, the exposure measurement field of view are moved in the same positional relationship.

As the parameters representing the characteristics of the object mentioned above, it is possible to use one color signal information, luminance signal information, and information such as the object's shape, temperature, or its characteristic contrast. An example of extraction based on signal information will be described.

In Fig. 5 (A), since the distances are the same, there is no need to adjust the focusing lens of the photographic lens, but in Fig. 5 (B)
), the subject moves to the upper right of the screen and the distance also changes, so the focusing lens moves according to the distance measurement results. Therefore, the size of the tracking field of view is changed by the tracking gate size determining means, which will be described later, and is always maintained at a size suitable for the subject, and focus detection and exposure adjustment are performed in this state, as shown in Fig. 5 (B). Although the exposure measurement field of view is not shown in the figure, it occupies the same relative position as that shown in Figure (A).

Here, since the movement between the subject and the camera is relative, the above-mentioned tracking effect works not only when the camera is fixed and the subject moves, but also when the subject stops and the camera moves. Alternatively, it functions effectively when both move together, and the size of the tracking field of view can be adjusted not only when the subject distance changes but also when the focal length of the lens changes.

In principle, the tracking field of view has a two-dimensional extent, but to simplify the explanation, it is shown in Fig. 6 (A).
Assume that the tracking field of view has a one-dimensional extension extending in the horizontal direction as shown in FIG. Also, the tracking field of view is A, B,
Suppose that it is divided into three parts (hereinafter each part is referred to as a pixel) of C. In order to configure a two-dimensional tracking field of view, for example, pixels extending vertically above and below pixel B or A, B, and C in the same figure may be provided, and time-series signals from each of the above pixels may be provided. The color difference signals (RY) and (B
-Y), as shown in FIG.
0a, 100b, sample hold (S/) () circuit 1
01a, 101b and A/D conversion circuits 102a, 102
B is subjected to various processes such as integration, sample hold, and A/D conversion, and is stored in the memories 103a and 1Q3b, respectively. When these stored values are plotted on the (RY) and (B-Y) orthogonal coordinates for each pixel A, B, and C, they are displayed as shown in FIG. 8, for example. In the figure, the points AQ, BO, and Co are respectively shown in Figure 6 (
It represents the signals extracted from each pixel of A, B, and C in A). Here, it is assumed that from pixel B, a signal representing only the ffl clothing of the subject, for example, is extracted, and from pixels A and C, a signal in which signals representing the clothing of the subject and the background are added together is extracted. Furthermore, assume that the background colors on the left and right sides of the subject in the same figure are different. Therefore, points AQ and Co have different positions on the color difference signal coordinates.

Next, when the subject shown in Fig. 6(A) moves to the right within the screen as shown in Fig. 6(B), the ratio of the subject to the background in pixels A and C changes, resulting in The signals obtained from A and C change as shown in FIG. 8 At and C1, respectively. On the other hand, since pixel B remains within the object as shown in FIG. 6(B), if the clothing is almost monochromatic, the signal obtained from pixel B will hardly change. Therefore, here, For simplicity, it is assumed that 81=BO. In this case, as shown in FIG. 8, point C1 approaches point no (=Bt), and point A1 approaches point Bo (=
Bt), the line segment BICL becomes the line segment BoC,
The line segment AlB1 becomes smaller than the line segment AoBo. Conversely, if the line segment BICI becomes larger than the line segment BoC, and the line segment AlB1 becomes smaller than the line segment AOB, it means that the subject is moving to the left in FIG. 6(B). Assuming that the background color is the same on both the left and right sides of the subject, when the subject moves within the screen to the right in Figure 6 (B), the above point A1 is located on the extension of the line segment AoB. Therefore, the point C1 is located on the line segment BoC. This automatic tracking means can be applied to either of the above cases.

In order to detect the movement of the tracked subject based on the above-mentioned principle, it is sufficient to detect the change in the length of the line segments AB and BC in FIG. 8, for example, as shown in FIG. 9.

FIG. 10 shows details of the color detection circuit 42, memory 43, and movement determination circuit 44 shown in FIG. 9 as an example of a circuit that performs the above processing. In FIG. 9, elements having the same configuration and function as the elements or circuits in FIG. 1 or 3 are:
The same reference numerals as these will be given and detailed explanation will be omitted.

The signal processing circuit 7 simultaneously processes color difference signals (RY) and (
B-Y) to the tracking gate setting circuit 40, and the luminance signal Y to A.
It is output to the F gate setting circuit 41 and the AE gate circuit 8. The output of the tracking gate setting circuit 40 is supplied to a color detection circuit 42 to detect the color of the subject, which is stored in a memory 43 via manual mechanical input means such as a switch (not shown). Note that the color detection circuit 42 is similar to the planting circuit 100 shown in FIG. Temporarily record the sample hold circuit 101, A/D conversion circuit 102, and their outputs t1
It includes a memory 103 for i. The above process is
1/60, which is the period of one field of a television signal
This is done according to its average value during a period of seconds or several fields thereof. In the following, both will be explained as being processed in one field period.

In the next field, the newly extracted signal and the signal stored in the memory 43 are compared in the movement determination circuit 44, and the presence or absence of movement of the subject and the direction of movement of the subject are detected. If there is movement, the tracking gate setting circuit 40 is controlled by the gate movement circuit 45 to move the tracking field of view, perform the same calculation in the first field, and repeat the above process until tracking is completed. return.

When tracking is completed, the gate moving circuit 45 moves A
The focus detection field of view set by the F gate setting circuit 41 is set to the same relative position as the tracking field of view, and the automatic focus detection circuit 14 uses the video signal (output of the signal processing circuit 7) within this focus detection field of view, for example. Focus detection is performed by known means such as mountain climbing control, and the output drives the motor M via the AF motor drive device 15 to control the position of the focusing lens 1.

Furthermore, in the apparatus shown in FIG. 9, the AF gate movement signal generated by the gate movement circuit 45 is also transferred to the AE gate signal generation circuit 11, and the timing of the AE gate movement signal generated by the circuit is adjusted according to the AF gate movement signal. Since it is controlled, the exposure measurement field of view can be moved to track the focus detection field of view, and automatic exposure adjustment can be performed at the new movement position.

In Fig. 9, Pl is a position sensor that detects the absolute position of the focusing lens 1 (corresponding to the subject distance), and Pl is a position sensor that detects the absolute position of the zoom lens 2 (corresponding to the focal length). It is a blind sensor that
Tracking gate size determination circuit 46 based on these signals
is the tracking gate setting circuit 40. The AF gate setting circuit 41 and the AE gate signal generation circuit 11 are controlled to determine the sizes of the tracking field of view, focus detection field of view, and exposure measurement field of view, respectively.

FIG. 10 shows the details of the color detection circuit 42, memory 43, and movement determination circuit 44 described above, and shows the details of the color detection circuit 42, memory 43, and movement determination circuit 44. ) signal and (B-Y) signal to distance calculation circuit 5
1, the length DAo, 80 of the line segment AoB on the (R-Y) and (B-Y) coordinates in FIG. 8 is determined and stored in the memory 52.
is memorized. From the next field signal.

Similarly, DAl, Bl or DAl, 8Q are obtained. Here, for simplicity, consider the case where 81=B, DAI-81''DAL, EIG, and the divider 53 calculates DAL, BO/DAO, [lO. This value is The comparator circuit 55 compares the first threshold value set by the threshold setter 54 and outputs "1" to the movement determination circuit 44 if there is a change exceeding the threshold value. From circuit 61 to comparison circuit 65
DQt-no/Dco, a by the circuit up to.

is calculated, and if there is a change exceeding the second threshold, the comparison circuit 65 outputs "t" to the movement determination circuit 44. To explain a specific numerical example, in the example shown in FIG. 8, both the first and second thresholds are set to 2, and DAl, BO/DAQ, BO=2.2°Dcz, no/
Since Dco and ao=0.36, only the comparator circuit 55 outputs "1". In this case, the movement determination circuit 44 generates a signal that delays the gate setting timing by a predetermined time (eg, about 1/125 of one horizontal scanning period in the case of the NTSC system). Conversely, if only the comparison circuit 65 outputs 1", the movement determination circuit 44 generates a signal that advances the gate setting timing by the above-mentioned predetermined time. In the latter case, when the subject moves to the left in FIG. Therefore, in response to the output "1" of the comparator circuit 55 or 65, the movement determination circuit 44 generates a signal that changes the gate setting timing by, for example, the above-mentioned predetermined time, and in response to this signal, the gate movement circuit 45 changes the gate setting timing. As mentioned above, the tracking gate setting circuit 4
By controlling the 0 and AF gate setting circuit 41,
The tracking field of view and the focus detection field of view can be moved along with the movement of the subject, and focus detection can be performed at that position.

On the other hand, from the gate moving circuit 45 to the AF gate setting circuit 41
The gate movement signal transferred to the AE gate message is transferred to the same poem as the AE gate message. A gate signal is generated. therefore,
In the device shown in Figure 9 as well, the exposure measurement field of view is linked to the focus detection field of view, so it is possible to achieve proper exposure for the target subject as in partial metering or spot metering, and it is also possible to achieve stable exposure as in average metering or split metering. Exposure adjustment can be performed, and the waveform of the gate signal itself can be adjusted independently of the waveform of the gate signal for focus detection.
! l! The waveform can be made suitable for I light).

Next, regarding means for detecting subject movement when setting a two-dimensional tracking field of view, we will discuss patent application No. 59-1 filed by the present applicant.
The outline will be explained according to the specification of No. 19465. For example, when setting a tracking field of view extending in the horizontal and vertical directions, as in the case where pixels A, B, and C in FIG. In order to detect movement in the horizontal direction, in addition to the pair of movement detection circuits shown in FIG. , a common movement determination circuit (for example, 44 in FIG.
) may be configured to supply the outputs of a total of four comparison circuits of these two pairs of movement detection circuits. If, for example, upward movement information is received from the second pair of movement detection circuits, it will be determined based on both information that the subject has moved relatively toward the upper left within the screen.

(Modified embodiment of this invention when equipped with automatic tracking focus detection means) (Figures 11 to M13) FIG. 11 shows the main part of a modified embodiment of this invention when equipped with automatic tracking focus detection means The main point is to supply the output luminance signal of the AF gate setting circuit 41 to the automatic focus detection circuit 14 and also to the automatic exposure adjustment circuit 9 so that the focus detection field of view is also used as the exposure measurement field of view. That's what I did. Note that when the exposure measurement field of view and the focus detection field of view are made to have different sizes, especially when the former is made smaller than the latter, an auxiliary gate circuit may be provided between the AF gate setting circuit 41 and the automatic exposure adjustment circuit 9. good. In this case, the auxiliary gate circuit is controlled by the output signal of the gate moving circuit 45, for example.

According to the configuration shown in FIG. 11, the AE gate signal generation circuit and, in some cases, the gate circuit for supplying the required luminance signal to the automatic exposure adjustment circuit 9 can be omitted, so that the automatic exposure adjustment means and the automatic exposure adjustment circuit 9 can be omitted. The circuit scale can be considerably reduced compared to a video camera in which a focus detection means is provided independently.

FIG. 12 shows the focus detection field of view F in the embodiment of FIG.
F, exposure measurement field of view EF, and tracking field of view TF In order to show the relationship among the three, the positional relationship of the champion is shown assuming that they are all displayed on the finder screen. In the embodiment shown in FIG. 11, the focus detection field FF and the exposure measurement field EF are shared, so they occupy the same area in FIG. 12.

FIG. 13 shows still another modified embodiment of the present invention in which automatic tracking means is provided, in which the exposure measurement field of view is selectively linked with the tracking field of view or the focus detection field of view. This is what I did. The output of the tracking gate setting circuit 40 or the AF gate setting circuit 41 is changed over by the switch 48.
is inputted to the automatic exposure adjustment device M49 via the above, and automatic exposure adjustment is performed in the same manner as in the previously described embodiments. When the exposure measurement field of view is linked to the tracking field of view or the focus detection field of view, the automatic exposure adjustment device 49 uses not only the automatic exposure adjustment circuit 9 shown in FIG. 1, 3, or 9 but also the AE gate circuit 8 (see FIG. In this case, the analog switch 8') and the AE gate signal generation circuit 11 are included, but if the field is used also as the tracking field or the focus detection field, the AE gate circuit 8 or the analog switch 8' is included.
Also, the AE gate signal generation circuit 11 is unnecessary.

(Effects) As described above, according to the present invention, the focus detection means, the automatic exposure adjustment means, and the exposure measurement field of the automatic exposure adjustment means are set to the focus detection field of view I++ of the focus detection means. −
Amashima Seven Deaf One Guy Confused T Day Carp? Even if the subject moves relative to the camera, the exposure measurement field of view can always match the focus detection field of view, so it is useful for shooting subjects that are intended to be photographed, such as with partial metering or spot hm light. On the other hand, it is possible to always perform appropriate exposure, and stable exposure adjustment such as average metering or split metering can be performed no matter where the subject moves within the photographic screen.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the overall configuration of an embodiment of the camera of the present invention, FIG. Figure 3 is a block diagram showing an example of a focus detection field setting device that selects an arbitrary division from the focus detection field divisions shown in Figure 2. Figures 4 (A) and (B) show the focus detection field of view and subject in a conventional camera. An explanatory diagram showing the relationship with the image. 5 to 10 show specific examples of the automatic tracking focus detection device according to the embodiment of the present invention, and FIGS. 5(A) and (
B) is an explanatory diagram showing the relationship between the focus detection field of view, exposure measurement field of view, and subject image when the above automatic tracking focus detection device is applied, and Figures 6 (A) and (B) are the above automatic tracking focus detection An explanatory diagram showing the relationship between the tracking field of view and a subject image when the tracking field of view is divided in the device. Fig. 7 is a block diagram of a device that processes signals obtained from the divided tracking field of view in Fig. 6. Fig. 8 is an explanatory diagram showing a situation in which signals obtained from the device shown in FIG. 7 are plotted on a two-dimensional surface, FIG. 9 is a block diagram showing an example of the above automatic tracking focus detection device, and FIG. A block diagram showing the details of the main parts of the device,
FIG. 11 is a block diagram showing the main parts of a modified embodiment of the present invention in which an automatic tracking focus detection device is provided, and FIG. FIG. 13 is an explanatory diagram showing the relationship between the Δ field of the present invention and a subject image when equipped with an automatic tracking focus detection device, and FIG. 15 is an explanatory diagram showing the relationship between a camera equipped with a conventional automatic exposure adjustment device. FIG. 2 is a block diagram showing the main parts of. Explanation of symbols 1: Focusing lens, 2: Zoom lens, 3: Aperture, 4=
Relay lens, 5: C, C, D as imaging means, 7
: Signal processing circuit, 8: AE gate circuit, 9: Automatic exposure adjustment circuit, 10: Aperture drive device, 11: AE gate signal generation circuit, 12: Focus detection field of view setting device, 13: AF
Gate circuit, 14 = automatic focus detection circuit, 27: joystick, 28 two microcomputers, 4o: tracking gate setting circuit, 41: AF gate setting circuit. 42: Color detection circuit, 43: Memory, 44: Movement determination circuit. Figure 4 (A) (B) Figure 5 (A) (B) Figure 7 Figure S Figure 9 Sheep Figure 10 Chicken

Claims (2)

[Claims] (1) A camera comprising: focus detection means; automatic exposure adjustment means; and means for moving the exposure measurement field of the automatic exposure adjustment means in conjunction with the focus detection field of the focus detection means. (2) The camera according to claim (1), wherein the focus detection field of view also serves as the exposure measurement field of view.