JPH08286228A - Counterlight detecting device for camera - Google Patents

Abstract

PURPOSE: To provide a counterlight detecting device for a camera capable of deciding counterlight by using a multiple focusing device. CONSTITUTION: The camera is provided with a multiple focusing sensor unit 51 including a pair of line sensors provided with plural photodetecting elements for receiving the light of an object and converting the light into an electrical video signal and capable of focusing different areas of the object based on a video signal group which is converted by each photodetecting element in different areas on a pair of line sensors, and a photometry sensor unit 37 capable of measuring the average luminance of the object, and also, the camera is provided with a CPU 31 for detecting the highest luminance value among each video signal detected by the multiple focusing sensor unit 51, calculating the average luminance value of the video signal in each range finding area, calculating a 1st luminance difference as a difference between the highest luminance value and the average luminance value, comparing the 1st luminance difference with a previously set 1st counterlight decision value and then deciding that the light is the counterlight when the 1st luminance difference is larger than the 1st counter light decision value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backlight detection device in a camera equipped with a passive distance measuring device.

[0002]

2. Description of the Related Art In conventional cameras,
In order to determine whether the light is backlit by the function of the camera, it is necessary to measure a plurality of subject areas. for that purpose,
It was necessary to provide a plurality of photometric sensors capable of photometrically measuring a plurality of subject areas, or to use a so-called split photometric sensor.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a backlight detection device for a camera, which is capable of determining a backlight using a multi-range finding device.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the fact that a passive distance measuring device detects the brightness of a subject in a predetermined area by a plurality of sensors. The present invention made from this point of view includes a pair of line sensors including a plurality of light receiving elements that receive subject light and convert the light into electrical video signals, and the light receiving elements in different regions on the pair of line sensors. A multi-range-finding device comprising: a multi-range-finding device capable of range-finding different regions of a subject on the basis of a video signal group converted by; and a photometric unit capable of measuring an average luminance of the subject. A maximum luminance value is detected from among the respective detected video signals, an average luminance value of the video signals in each of the distance measurement areas is calculated, and a first luminance which is a difference between the maximum luminance value and the average luminance value. A difference is calculated, and the first brightness difference is compared with a preset first backlight judgment value to determine the first brightness.
It is characterized in that it is provided with a backlight determining means for determining backlight when the difference in luminance is larger.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to illustrated embodiments. 1 and 2 are a front view and a rear view of an embodiment of a lens shutter camera incorporating a strobe to which the present invention is applied. A zoom lens 13 is provided in front of a camera body 11 of this lens shutter type camera, and a metering window 15, an AF auxiliary light projecting window 16, a viewfinder window 17, a passive AF light receiving window 18 and a strobe light emitting window 1 are arranged above the zoom lens 13.
9 is equipped. Although not shown, a photometric sensor, an AF auxiliary light projecting element, a finder optical system, a passive AF unit, and a stroboscopic light emitting section are respectively arranged in the rear camera body 11 of these windows 15 to 19 as well known. ing.

A release button 21 and a flash button 23 are arranged on the upper surface of the camera body 11.
The release button 21 is interlocked with the photometric switch SWS and the release switch SWR, and as is well known, the photometric switch SWS is turned on by half-pressing, and the release switch SWR is turned on by full-pressing. Further, a zoom lever 25 that can zoom the zoom lens 13 in the tele direction or the wide direction when the camera body 11 is tilted to the tele side or the wide side is provided on the upper rear surface of the camera body 11. This zoom lever 2
5 is teleswitch SWTELE and wide switch SWWI
In conjunction with DE, when the zoom lever 25 is tilted to the tele side or the wide side, the tele switch SWTELE and the wide switch SWWIDE turn on.

Further, on the front surface of the camera body 11, a self-timer 2 which displays a self-timer operation and also functions as an exposure notice lamp for giving an advance notice of exposure at the time of photographing.
7 are arranged. Further, a green lamp 28 and a red lamp 29 for displaying distance measurement and strobe information are provided near the eyepiece frame on the back surface of the camera body 11.

FIG. 3 is a block diagram showing a circuit configuration of the lens shutter type camera. The camera body 11 is provided with a microcomputer (CPU) 31 that also controls general camera control such as automatic focus adjustment (AF) processing, automatic exposure control processing, film winding and rewinding processing. The CPU 31 has, as switches, a photometric switch SWS, a release switch SWR, a telezoom switch SWTELE, and a wide zoom switch SWWIDE.
Has been entered. The CPU 31 receives the on / off operation of these switches and executes a predetermined process.

The DX code reading circuit 33 reads the DX code relating to the ISO speed from the DX codes of the film cartridge loaded in the camera body 11, and CP
Output to U31. The zoom code input circuit 35 detects the current focal length data of the zoom lens 13 via a zoom code plate (not shown) and outputs it to the CPU 31. The photometric sensor unit 37 includes a photometric sensor (not shown), receives the subject light incident from the photometric window 15 by the photometric sensor, and outputs a photometric signal converted into a current or a voltage corresponding to the subject brightness to the CPU 31. The CPU 31 calculates the subject brightness Bv on the basis of this photometric signal, reads the subject brightness Bv via the DX code reading circuit 33, and converts the ISO sensitivity Sv based on the appropriate shutter speed Tv and the appropriate aperture value Av. Is calculated. The AF auxiliary light projecting circuit 39 detects when the subject brightness is low or when the CPU 31 determines that the contrast of the subject is low.
Under the control of the CPU 31, the subject is irradiated with a contrast pattern.

The passive AF sensor unit 51, which also functions as a photographing distance detecting means, receives a subject light flux and outputs a pair of two-dimensional video signals each including a plurality of video signals, which will be described in detail later. The CPU 31 which takes in the video signal stores it in the internal RAM in units of each video signal. Then, the CPU 31 executes distance measurement calculation based on the pair of stored video signals, calculates the focusing lens drive amount of the shutter / aperture / focus drive circuit 41, and drives it.

Further, this camera has a release switch S
When the WR is turned on, the shutter speed is calculated based on the shutter speed Tv and the aperture value Av previously calculated by the CPU 31.
The aperture / focus drive circuit 41 drives the shutter / aperture.

When the tele-zoom switch SWTELE or the wide-zoom switch SWWIDE interlocked with the zoom lever 25 is turned on, the CPU 31 causes the zoom motor drive circuit 45 to operate.
The zoom motor M is driven through the zoom lens 13 to zoom (tele zoom, wide zoom). The zoom motor M drives to a storage position where the lens barrel of the zoom lens 13 fits within the external appearance of the camera body 11 (shortest) when the power is off, and to a wide end position when the power is on. The zoom lens 13 has a tele end macro function, and when a macro switch (not shown) is turned on, the zoom motor M is driven to drive the zoom lens 13 to a macro position beyond the tele end position. Lens positions such as the focal length and macro position of the zoom lens 13 are
It is detected by the zoom code input circuit 35.

The self lamp 27, the green lamp 28 and the red lamp 29 are driven by a lamp driving circuit 45. Although the above is the main members of the present camera, the present camera includes known members such as a battery, a display panel for displaying various information, and a film winding / rewinding motor.

FIG. 4 is a more detailed block diagram of the AF sensor unit 51 of this embodiment. As shown in FIG. 4, the AF sensor unit 51 forms left and right images (condensing).
Lenses 52L, 52R, left and right line sensors 53L, 5
3R, left and right quantizers 54L and 54R, and calculator 55
It has. The left and right imaging lenses 52L, 52
The R, left and right line sensors 53L and 53R, and the left and right quantizers 54L and 54R have the same configuration as left and right, and operate similarly as left and right.

The light flux of the subject is composed of left and right imaging lenses 52L,
52R corresponding left and right line sensors 53L, 5
An image is formed on or after the 3R. The photodiodes of the left and right line sensors 53L and 53R that receive the subject light flux photoelectrically convert the received subject light, and generate an electrical signal (voltage or current) corresponding to the brightness in the left and right quantizers 54.
Output to L and 54R. Left and right quantizers 54L and 54R
Converts the amount of light received by each photodiode into time. That is, each input electric signal is integrated, the time when the integrated value reaches a constant value is measured, and each measured time is stored.
Then, the left and right quantizers 54L and 54R, when all the electric signals reach a predetermined integral value and store the measurement time,
Alternatively, when a certain period of time elapses before reaching, a certain period of time is stored as a measurement period for the photodiode for which integration is not completed, and then the stored measurement period data is sequentially output to the CPU 31 as video data. CPU31
Stores these video data in memory.

FIG. 5 shows the relationship between the distance measurement area used for multi-distance measurement and the line sensor. In this embodiment,
The central distance measuring area mc is provided with three distance measuring areas including the left and right distance measuring areas ml and mr set on the left and right sides thereof. Distance measuring areas (light receiving areas) MC and M on the left and right line sensors 53L and 53R corresponding to the distance measuring areas mc, ml and mr, respectively.
L and MR are shown in FIG. Each of the left and right line sensors 53L and 53R of this embodiment has a light receiving unit of 12
Eight photodiodes are provided, and data from 36 consecutive photodiodes are used as each distance measuring area.

The operation of the lens shutter type passive AF camera to which this embodiment is applied will be described in more detail with reference to the flow charts shown in FIGS. This process is CP
It is executed by the CPU 31 based on the program stored in the internal ROM of U31.

When a main switch (not shown) is turned on, this flow chart is entered, and first, various switches S
The on / off state of W is input (S101). And
Tele zoom switch SWTELE, wide zoom switch S
Check if WWIDE is on (S10)
3, S113). If the tele-zoom switch SWTELE is on, it has not reached the tele end and is not in the macro position, the tele-direction drive processing of the zoom motor M is executed and the process returns to S101 (S105, S107, S109, S1.
01), if it is in the macro position, the zoom lens 13 is moved to the tele end position and the process returns to S101 (S107, S1).
11, S101). In the tele-direction driving process, although not shown in detail, while the tele-zoom switch SWTELE is turned on, the zoom motor M is driven in the tele-direction until the zoom lens 13 reaches the tele end, and the zoom switch SW is turned on.
When is turned off or reaches the tele end, the zoom motor M is stopped and the process returns to S101.

If the wide zoom switch SWWIDE is on, if the wide end is not reached and the macro position is not reached, the wide direction drive processing of the zoom motor M is executed and the process returns to S101 (S103, S113, S115). , S
117, S119, S101), if in the macro position,
The zoom lens is moved to the telephoto end position and the process returns to S101 (S117, S121, S101).

Whether both the tele-zoom switch SWTELE and the wide-zoom switch SWWIDE are off (S1
03, S113), whether the tele end has been reached by turning on the tele zoom switch SWTELE (S103, S105, S113),
If the wide end has been reached by turning on the wide zoom switch SWWIDE (S103, S113, S115), whether or not the photometric switch SWS has changed from off to on, that is, turning off last time, turning on this time Check whether or not (S113, S123 or S11
5, S123). Then, if it is changed from off to on, the photographing processing subroutine is called (S123, S).
125). When the shooting process ends, the process returns to S101.

The photographing processing subroutine of S125 will be described in detail with reference to the flowcharts shown in FIGS. When this subroutine is entered, the DX code reading circuit 33 is activated, the ISO sensitivity is input, and the battery voltage is checked (S201, S203). If the voltage of the battery is lower than the predetermined value, there is a possibility that normal shooting processing may not be possible, so the process returns, and the shooting processing is advanced under the condition that the battery voltage is a normal value (S2).
05).

If the battery is normal, the passive AF circuit 51 is activated to input the image data and the subject distance is obtained (S207). The photometric circuit 37 is activated to input the photometric data, the main photometric value and the sub photometric value are obtained, and the shutter speed and aperture value are calculated by a predetermined exposure calculation algorithm (S209, S211). Further, processing is performed to determine whether or not the distance measurement data is default (S2
13). Here, the default, that is, the distance measurement error occurs, for example, when the defocus amount cannot be obtained because the contrast of the subject is too low. In the case of a distance measurement error, the green lamp 28 is blinked to display that the distance measurement error has occurred (S215, S221). Even if the distance measurement error does not occur, the green lamp 28 is made to blink even if the subject distance is closer than the shortest subject distance that can be focused (S215, S217, S221). If it is neither a ranging error nor a short distance, the green lamp 28 is lit (continuously lit) (S215, S217, S21).
9).

Next, it is checked whether or not the strobe light is emitted. When the strobe light is emitted, a flashmatic (FM) operation is executed to obtain the aperture value Av (S225). When the FM calculation is completed, it is checked whether or not the charging is completed. If the charging is completed, the red lamp 29 is turned on, and if the charging is not completed, the red lamp 29 is made to blink and S
Proceed to 233 (S227, S229 or S231).
If you do not want the flash to fire, the above steps S227-S
The processing of 231 is skipped and the process proceeds to S233.

In S233, the states of the photometric switch SWS and the release switch SWR are input. Then, it waits for the release switch SWR to be turned on (S233,
S135, S237). The release switch SWR
If the photometric switch SWS is turned off before turning on, both the green lamp 28 and the red lamp 29 are turned off and the process returns (S237, S239).

When the release switch SWR is turned on,
The self lamp 27 is turned on to notify the release, and the green and red lamps 28 and 29 are turned off (S241). Then, the focus adjustment lens is driven, the self lamp 27 is turned off to perform the exposure process, the film winding / rewinding process is executed, and the process returns to the main routine (S243, S24).
5, S247, 249).

For details of the distance measurement calculation processing in S207,
This will be described with reference to FIGS. 10 and 11. When entering the distance measurement calculation subroutine, first, various data related to distance measurement is read.
It is read from the OM and RAM (S301). It is checked whether the main photometric value, which is one of the read data, is less than or equal to the auxiliary light emission level, and if it exceeds the emission level, the auxiliary light projecting circuit 39 is turned off (S303, S30).
5) If it is below the emission level, the auxiliary light projecting circuit 39 is turned on to start projecting the auxiliary light (S303, S307).
In the present specification, the “main photometric value” is a photometric value measured by the photometric circuit 37, and the “sub photometric value” is a photometric value measured by the AF sensor unit 51. is there.

The integration end time (Time Up) is set, the flag Fi is set to 0, the AF sensor unit 51 is reset, that is, the stored data is cleared, and then the AF is performed.
Start integration on the sensor unit 51 (S30
9, S311, S313). In this embodiment, the CPU 31
The AF sensor unit 51 to which the reset signal is input from executes the integration process, and the left and right line sensors 53L and 53R
Output the data of each photo sensor unit to the CPU 31, and
The PU 31 stores each in memory.

When the memory is completed, the flag i is checked (S315). Since the flag i is 0 at the first time after entering the distance measuring process, the sub photometric process is executed (S3).
17). This sub-photometry processing is performed by the AF sensor unit 51.
This is a process of obtaining a sub-photometric value 1 which is the difference between the maximum luminance and the average luminance and a sub-photometric value 2 which is the intermediate value of the difference between the average luminances of the respective areas, based on the amount of light received by the photodiode.

Next, the distance measurement area used in the distance measurement calculation is set (S319). That is, the right sensor start address NR and the left sensor start address NL at which the video data reading is started are set. Then, a predetermined number of video data starting from the address set in the distance measurement area is read, and a data correction process for aligning the left and right video data levels is performed (S321, S323). Based on the corrected video data, the distance measurement value calculation is executed to calculate the subject distance (S3).
25). The distance measurement value calculation includes calculation of the evaluation function f (N).

Distance measurement value calculation processing (S319 to S325)
Is executed for all three distance measuring areas (S32).
7, S319-S325).

After the distance measurement values (subject distances) have been calculated for all three distance measurement areas, selection processing is performed to select one distance measurement value to be used for focus adjustment from these distance measurement values ( S329). The selection process may be, for example, to select the closest distance measurement value.

After the distance measurement value selection processing is completed, the assistance is performed only once on the condition that normal distance measurement values cannot be obtained from all the distance measurement areas (all the distance measurement values are abnormal). The light projecting circuit 39 is driven to project the auxiliary light, and S313 to S
The distance measurement process of 329 is re-executed (S331, S333,
S335, S337, S313 to S329).

When normal distance measurement data is obtained from one or more distance measurement areas by the first processing of S313 to S327, or when the second processing of S313 to 327 is completed, all distance measurement is performed again. It is checked whether the data in the area is an error, and if even one piece of normal data is obtained, the selected object distance data is driven by the lens (LL).
Convert to data and return (S337, S341,
S343). When the data in all the distance measurement areas are in error, the distance measurement error flag is set and the process returns (S339, S343).

The AF sensor reset process in S313 will be described in more detail with reference to the subroutine shown in FIG. In this AF sensor reset processing, each circuit and memory in the AF sensor unit 51 are reset to start integration, and the reference brightness BvS is calculated based on the output of the photodiode having the shortest integration end time.
This is a process for obtaining 0 (the highest brightness value).

AF When this subroutine is entered, first the reference brightness measurement timer is started and the AF sensor circuit 51 is reset (S401, S403). That is, integration is started after the charges accumulated by the left and right line sensors 53L and 53R are swept out. When the integration is started, the outputs of the photodiodes of the left and right line sensors 53L and 53R are quantized by the quantization units 55L and 55R, and the calculation unit 56
Calculate time data with.

When the integrated value of one of the photodiodes reaches a predetermined value, the arithmetic unit 56 outputs a reference integration end signal to the CPU 31. When the CPU 31 receives the reference integration end signal, the CPU 31 stops the reference brightness measurement timer, and sets the reference based on the time data required to reach the predetermined integration value and the correspondence table data (not shown) between the integration time and the brightness value. The brightness BvS0 is calculated (S405, S407,
S409). The outputs of the other photodiodes are quantized by the quantizers 55L and 55R, and the arithmetic unit 56
The integration and time data calculation are performed in the memory.

FIG. 13 shows the sub-photometric processing of S317.
This will be described in more detail with reference to the subroutine shown in.
The sub-photometry process is a process of calculating data necessary for backlight determination based on the image data detected by the AF sensor unit 51.

In this process, first, the average luminance value A for all the image data of the one line sensor 53L, 53R is calculated, and the difference from the sub-photometric value BvS0 (first
Brightness difference) and calculate the difference as sub-photometric value 1 (sub 1)
(S451, S453, S455).

Next, for each of the photometric areas MC, MR, ML, the sub-average brightness values AC, AR of the brightness (intensity) of the image data group included in these photometric areas MC, MR, ML.
AL is calculated (S457, S459, S461). The absolute value D (n) of the difference between the two sub average luminance values AC, AR, and AL is calculated (S463). Then, the absolute values D (n) of the differences are rearranged in descending order, and the absolute values D (n) of the intermediate differences (second sub-brightness difference) are substituted into the sub-photometric value 2 (sub-2) ( S465, S46
7).

FIG. 14 shows the AE calculation processing of S211.
Will be described with reference to. This AE calculation process is characterized in that it is determined whether or not there is backlighting using the sub-photometric value 1 and the sub-photometric value 2 detected in the sub-photometric process.

In this AE calculation process, first,
The second backlight judgment levels Lv1 and Lv2 are set (S5).
01). The difference between the main photometric value measured by the photometric sensor unit 37 and the sub photometric value 1 is substituted for the first luminance difference S1 (S503). It is checked whether the first brightness difference S1 is larger than the first backlight judgment level Lv1 (S50).
3, S505). If the first brightness difference S1 is larger, it can be determined that the backlight is backlit. Therefore, the strobe circuit 43 is turned on to start strobe emission preparation, and the backlight compensation amount is calculated by the following formula. Δbv = S1−L1 However, in the present embodiment, L1 is 1.5 Ev. On the other hand, if the first luminance difference S1 is equal to or lower than the first backlight determination level Lv1, it can be determined that the backlight is not the backlight.
5, S511).

In step S511, the sub-photometric value 2 is set to the second value.
It is checked whether it is larger than the backlight judgment level Lv2 of. The sub-metering value 2 is the second backlight judgment level Lv.
If it is larger than 2, it is checked whether or not the backlight correction amount Δbv is less than the difference between the sub metering value 2 and the second predetermined value L2 by turning on the strobe circuit 43 to start the light emission preparation. For example, the difference between the sub-correction amount 2 and the second backlight judgment level Lv2 is substituted into the backlight correction amount Δbv and S519 is entered.
(S511, S513, S515, S517).
That is, the smaller one is set as the backlight correction amount Δbv.
In this embodiment, L2 is 1.5 Ev.

In the processing of S511 to S517, it is checked whether or not the sub-photometric value 2 is larger than the second backlight judgment level Lv2. If so, the difference between them is reset as the backlight correction amount Δbv.

At S519, backlight correction limit processing is executed. That is, the backlight correction amount Δbv calculated in S509 or S517 is the correction limit value, for example, ± 3E.
When it exceeds v, the backlight correction amount Δbv is set to ± 3 Ev.
To change.

When the backlight correction limit processing is completed, the backlight brightness Bv is corrected by subtracting the backlight correction value Δbv from the main photometric value (object brightness Bv) (S521). Then, based on the subject brightness Bv and the ISO sensitivity Sv, A
The E calculation is executed to obtain the shutter speed Tv and the aperture value Av (S523). Furthermore, the calculated shutter speed T
AE data limit processing is performed to keep v and the aperture value Av within the shutter and aperture capability range of the camera, and the process returns (S525). It should be noted that in the present embodiment, when it is determined that there is backlight, both flash emission and backlight correction are performed.
Either one may be performed.

As described above, according to the present embodiment, since the backlight determination is performed by using the output of the passive distance measuring sensor unit 51, it is not necessary to use the divided photometric sensor for photometry.

In the present embodiment, the distance measurement is performed in the center and left and right sides.
Although the configuration is performed for each area, the distance may be measured for four or five or more areas, but in order to determine the backlight, an area apart from the central area of the photographing screen to the left and right can be measured. Configuration is desirable.

[0048]

As is apparent from the above description, according to the present invention, a pair of line sensors having a plurality of light receiving elements for receiving subject light and converting it into an electrical video signal are included. In a camera provided with a multi-ranging device capable of measuring a different area of a subject based on a video signal group converted by each light receiving element in a different area above, and a photometric means capable of measuring an average luminance of the subject, The backlight determining means detects the highest luminance value from the respective video signals detected by the multi-ranging device, calculates the average luminance value of the video signals in the respective distance measuring areas, and calculates the highest luminance value and the average luminance. A first brightness difference, which is the difference from the value, is calculated, and the first brightness difference is compared with a preset first backlight judgment value to determine the first brightness difference.
Since it is determined that the backlight is backlit when the difference in luminance is larger, it is not necessary to use a divided photometric sensor for photometry, and the configuration is simplified.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a lens shutter camera equipped with a distance measuring device of the present invention.

FIG. 2 is a rear view of the lens shutter camera.

FIG. 3 is a block diagram showing a main part of a circuit configuration of the lens shutter camera.

FIG. 4 is a diagram showing an example of a configuration of an AF distance measuring unit mounted on the lens shutter camera.

FIG. 5 is a diagram showing a relationship between a distance measuring area of the AF distance measuring unit and a light receiving area (distance measuring area) on a line sensor.

FIG. 6 is a diagram illustrating a mutual relationship between distance measurement areas on the line sensor.

FIG. 7 is a flowchart showing the main processing of the present embodiment.

FIG. 8 is a diagram showing a subroutine relating to the shooting process.

FIG. 9 is a diagram showing a subroutine relating to the shooting process.

FIG. 10 is a diagram showing a subroutine relating to the distance measurement processing.

FIG. 11 is a diagram showing a subroutine relating to the distance measurement processing.

FIG. 12 is a diagram illustrating a subroutine relating to AF sensor reset processing.

FIG. 13 is a diagram showing a subroutine relating to sub-photometry processing.

FIG. 14 is a diagram showing a subroutine relating to AE calculation processing.

[Explanation of symbols]

 11 camera body 13 zoom lens 31 CPU (backlight judging means) 33 DX code reading circuit 35 zoom code input circuit 37 photometric sensor unit (photometric means) 51 AF distance measuring sensor unit (multi-distance measuring means)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G03B 15/05 G02B 7/11 NH 04N 5/235 G03B 3/00 A

Claims (6)

[Claims] 1. A pair of line sensors including a plurality of light receiving elements for receiving subject light and converting the light into an electric image signal, and images converted by the respective light receiving elements in different regions on the pair of line sensors. A camera provided with a multi-distance measuring device capable of distance-measuring different regions of a subject based on a signal group, and a photometric means capable of measuring an average luminance of the subject, each of which is detected by the multi-distance measuring device. The maximum brightness value is detected from the video signal, the average brightness value of the video signal in each of the ranging areas is calculated, and the first brightness difference that is the difference between the maximum brightness value and the average brightness value is calculated. And a backlight determination unit that compares the first brightness difference with a preset first backlight determination value and determines backlight when the first brightness difference is larger. A backlight detection device for a camera having features. 2. The camera according to claim 1, further comprising a stroboscopic light emitting device, wherein the backlight determining means actuates the stroboscopic light emitting device when it is determined that there is backlight.
Backlight detection device for a camera characterized by the above. 3. The backlight detection device for a camera according to claim 1, wherein the backlight determination unit corrects the exposure value based on the first brightness difference when it is determined that the backlight is the backlight. 4. The backlight determining means according to claim 1 or 3, further calculates a sub-average brightness value of the video signal group for each of the distance measurement areas, and calculates another sub-average brightness value for each sub-average brightness value. The absolute value of the difference is calculated, the second sub-luminance difference corresponding to the intermediate value of the absolute values of these differences is selected, and the second sub-luminance difference is compared with the preset second backlight judgment value. And a backlight detection device for a camera having a function of determining backlight when the second sub-luminance difference is larger. 5. The camera according to claim 4, further comprising a stroboscopic light emitting device, wherein the backlight determining means actuates the stroboscopic light emitting device when it is determined that the backlight is a backlight.
Backlight detection device for a camera characterized by the above. 6. The backlight determination unit according to claim 4, further comprising: when the difference between the second sub-luminance value and the predetermined value is smaller than the backlight correction amount, reset the difference as the backlight correction amount. A backlight detection device for a camera, which is characterized in that