JPH02161882A - Sensitivity adjustor for image pickup element - Google Patents

Abstract

PURPOSE:To easily and exactly adjust the variance of sensitivity of an image pickup element at the time of assembling an electronic shutter by providing a control means in which a correction value corresponding to a switch input of a switch input terminal for setting the correction quantum corresponding to the variance of image pickup sensitivity of the image pickup element is stored. CONSTITUTION:At the time of assembling, the variance quantum of sensitivity of an image pickup element 9 is checked, and based on the result of this check, switch input terminals 53, 54 of a control means 10 are set to a prescribed state. Accordingly, a correction value corresponding to a set state of the input terminals 53, 54 is outputted from the control means 10, and by this output, photometric data by a photometric sensor 6 for controlling an exposure is corrected, and a shutter speed, namely, an exposure time is adjusted. In such a way, at the time of assembling the image pickup element 9, by only setting a state of the switch input terminals 53, 54 of the control means 10 in accordance with the variance of element sensitivity, the variance of each sensitivity of the image pickup element 9 can be corrected easily and exactly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a device that uses an image sensor and corrects variations in sensitivity of an image sensor in a so-called electronic shutter.

[Prior Art 1] An electronic shutter that controls exposure using a solid-state image sensor such as a CCD is known. This god's photographic element f is
There are variations in imaging sensitivity corresponding to the ISO sensitivity of the film for each element.

In a video recording device using this image sensor, such as an electronic still camera, by using the shutter function of the same element, there is no need for an aperture tJ1 structure for exposure adjustment. Due to the variation in
It is necessary to correct it.

[Problems to be Solved by the Invention] However, it is not easy to accurately adjust the variations in sensitivity of each image sensor for each electronic still camera in which the same image sensor is incorporated. Also, if there are variations in sensitivity,
The exposure control may not be done properly.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sensitivity adjustment device for an image sensor that can easily and accurately adjust variations in sensitivity of the image sensor when assembling an electronic shutter.

[Means for Solving the Problems] To achieve the above object, the present invention provides a sensitivity adjustment device for an image sensor in which exposure is controlled based on photometric data from a photometric sensor, in which variations in the imaging sensitivity of the image sensor are addressed. A switch input terminal for setting a corresponding correction amount is provided, and a control means is provided in which a correction value corresponding to the switch input is stored. It is designed to correct photometric data.

[Operation] According to the above configuration, the amount of variation in sensitivity of the image pickup device is checked during the assembly process, and the switch input terminal of the control means is set to a predetermined state based on the result of this check. As a result, the control means outputs a correction value according to the setting state of the input terminal, and the photometry data from the photometry sensor for exposure control is corrected using this output, and the shutter speed, that is, the exposure time is adjusted.

[Effects of the Invention] According to the present invention, the sensitivity of each image sensor can be easily and accurately determined by simply setting the state of the switch input terminal of the control means according to the variation in element sensitivity during the assembly process of the image sensor. Variations can be corrected.

Therefore, exposure control by the image sensor is properly performed,
For example, with an electronic still camera incorporating the same element,
It becomes possible to take pictures without variations.

(Hereinafter, blank space) [Example] A configuration diagram of an optical system according to an embodiment of the present invention is shown in Fig. 1. In the figure, 1 is a photographic lens including a zoom lens, and 2 is a photographic lens that passes through the photographic lens 1. A half mirror 53 with a low reflectance that guides a part of the light to the photometric sensor 6 has a half mirror only in the center and a total reflection mirror around the periphery, and is a main mirror 4 that guides the light transmitted through the mirror 2 to the pentaprism 5. 5 is a sub-mirror that totally reflects the light transmitted through the center of the main mirror 3 and guides it to the focus detection sensor 7; 5 is a pentaprism that guides the light reflected by the main mirror 3 to a finder (not shown); 8 is an optical low-pass The filter 9 is a solid-state imaging device (eg, CCD) arranged in a matrix and has a shutter function.

The photometric sensor 6 includes a photoelectric conversion element (for example, spc>
It has two types of sensors: one that measures light at the center of the shooting screen spot-wise and one that measures light around the periphery of the shooting screen. The sensor 6 is located at a position where the distance between the reflection point A of the half mirror 2 and the photometric point B of the sensor 6, and the distance Rc from the reflection point A to the imaging point C of the solid-state image sensor 9 are equal to 1lRb. , and is arranged so as to be equivalent to performing photometry on the tM image plane of the solid-state image sensor 9. In addition, the sensor 6 is placed in a position where the light it receives is not blocked regardless of whether the main mirror 3 is up or down, so that it can simultaneously measure light even when the solid-state image sensor 9 is exposed when the mirror is at. It has become.

The focus detection sensor 7 has, for example, two CCD line sensors that each receive images from different exit pupils of the photographic lens, and uses a phase difference detection method of the two images to determine the amount of focus shift or detect the amount of focus. It detects the amount of focus.

In the above configuration, when the photographer presses the shutter button halfway, a system controller (not shown) calculates the amount of defocus based on the output of the focus detection sensor 7, and
Based on this, the photographing lens 1 is driven and focused. After the object has been focused, the photometric sensor 6 measures the brightness of the object, and based on the brightness information, the system controller determines the charge N product time of the solid-state image sensor 9 (that is, the shutter opening time), The necessity of flash and the timing of flash emission are set by 7i4X. When the photographer fully presses the shutter button to release the camera, the main mirror 3 is flipped up, the sub-mirror 4 is folded, and exposure to the solid-state image sensor 9 is started. That is, the solid-state image sensor 9 starts accumulating charges. Further, the photometric sensor 6 starts photometry at the same time as the charge accumulation in the solid-state image sensor 9, and when it is detected that the amount of photometry has reached the appropriate exposure value, it stops the charge accumulation in the solid-state image sensor 9, and The accumulated charge is transferred to the analog memory section and the photographing is completed.

In addition, in the configuration of this embodiment, while the configuration of an eye reflex camera is included, the solid-state image sensor 9 has a shutter function,
Furthermore, the aperture mechanism has been removed to make the camera more compact and to simplify the mechanism. Therefore, the main mirror 3 and sub-mirror 4 placed in front of the solid-state image sensor 9 are configured to completely shield the low-pass filter 8 and the solid-state image sensor 9 from light, and form an image on a high-brightness object (for example, the sun). The photographic element 9 may
This prevents color fading (burning) of a color filter (not shown) provided in front of the camera, and also prevents the solid-state FFL image element 9 from accumulating unnecessary charges except at the time of release.

Next, FIG. 2 shows the system configuration of this embodiment.

In the figure, 10 is a system controller (CPUI) that controls the sequence of the entire camera section, and 23 is a system controller (CPLJ2) that controls the sequence of the video section. In addition, 11 is a focus detection COD for driving the lens and automatically focusing (AF).
A control circuit block consisting of a line sensor and an interface circuit section, which is an AP of the system controller 10.
The sequence controls the charge accumulation function and the function of sequentially A/D converting and outputting the accumulated charges. Further, 12 is a DC/DC converter that generates different power supply voltages for each circuit block and supplies power; 13
1 is a clutch circuit for switching the power of the motor M to the photographing lens 1, the main mirror 3, and the sub-mirror 4;
4 is a light source such as an AF auxiliary light source (LED) to add contrast between light and dark to a dark subject where distance measurement is not possible and to enable distance measurement, and a light source such as an LED that flashes while the self-timer is operating;
A driving IC 116 for driving the motor M is a photocoupler that generates a number of pulses corresponding to the amount of driving of the photographic lens. Further, reference numeral 17 is a photometric sensor, which includes a sensor 17a that measures the brightness at the center of the shooting screen as a spot, and a sensor 17b that measures the brightness around the shooting screen except for the center.
has. Further, 18 is a flash circuit, 19 is a display circuit including an LED display circuit 19a in the viewfinder and an LCD display circuit 19b on the top surface of the camera body, and 20 is a color temperature sensor circuit that measures the color temperature of the light source illuminating the subject. , 21 indicate switches including a switch linked to the shutter button and a mode changeover switch.

Here, each switch of the switches 21 is shown. SO is the main switch to prohibit camera operation when "open", and SL starts AE (auto exposure) and AP (auto focus). S2 is a release start switch.

S3' and S4 are set at the manufacturing stage of the camera to correspond to variations in the imaging sensitivity (i.e., the sensitivity of the output voltage to a constant exposure amount) corresponding to the ISO sensitivity of the film of the solid-state imaging device 9, which differs individually. These switches s3 and S4 handle 2-bit signals (A, B)
are configured, and the corresponding correction values γ (Ev) are stored in the system controller 10. When the above 2-bit signals (A, B) are input to the system controller 1o, the system controller 10 responds to the signals. A correction value γ is output, and the luminance measured by the photometric sensor 17 is corrected. That is, photometric sensor 1
7a performs photometry at the same time as photographing, and the timing of shutter release is controlled based on the photometry data. By correcting the photometry data, the shutter speed is controlled and the imaging sensitivity is corrected. For example, (0
,0)=O,OEv, (0,1)=+O13Ev,
(1,0)=-0,3Ev, (1,1)+0.5Ev
If the imaging sensitivity of the solid-state image sensor 9 is 0.3 Ev higher than the above, if the 2-bit signal (0, 1) is input to the system controller 10, the controller 10 will respond to (0°1). Yes +〇, 3Ev correction value γ
is output, and the photometric brightness of the photometric sensor 17 is +〇, 3Ev.
Since this is corrected, the shutter speed is increased by +0.3 Ev, the exposure amount is lowered by 0.3 Ev, and variations in imaging sensitivity are corrected. Note that by increasing the number of switches and increasing the number of bits and storing correction values corresponding to each bit signal in memory, the amount of correction can be made finer.

S5 sets the selected date information with the first switch 55-1 for selecting date information of year, month, day, hour, and minute;
It is a date switch consisting of a second switch 55-2 to be corrected, and S6 is a date switch that detects the open/closed state of the deck lid. 57-1 is a detection switch, and 57-1 is a floppy detection switch that detects whether or not a floppy disk for recording video signals is loaded in the camera;
Reference numeral 2 denotes a write-protection detection switch that detects whether or not write-protection is selected by a write-protection selection tab on the floppy disk.

S8 is a switch that detects whether or not the accessory slide copier is connected, and S9 is a switch that detects whether or not the accessory negative copier is connected.

S10 is a switch that detects the playback mode, and S11
is a field/frame switch that changes the recording format to field or frame.
S12 is a zoom encoder switch group that monitors the focal length of the zoom lens.

313 is a forced flash switch for forcing the flash to fire regardless of the brightness of the subject, and S14
S15 is a flash prohibition switch for forcibly disabling the flash, and S15 is a mode changeover switch for switching between single/self-timer shooting mode.

Next, 22 is a control IC, which controls the drive of each actuator such as the DC/DC converter 12 and the clutch 13 based on the control signal from the system controller 10, and controls the shutter speed of the solid-state image sensor 9 and the flash circuit 18. A of photometric data based on light emission timing 17
/D conversion circuit, appropriate exposure detection circuit, etc.

To explain this control IC 22, the voltage control circuit 2
2a is DC/D by DC/DC control signal.
The clutch control circuit 22b controls the on/off of the clutch 13 using a clutch control signal, and the self-control circuit 22c controls the light emission of the light source 14 using a self-control signal to control the motor. The circuit 22d controls starting of the motor M using a motor control signal. In addition, photo interrupter circuit 2
2e counts a number of pulses corresponding to the amount of lens rotation output from the photocoupler 16 and outputs them to the system controller 10. Further, the amplifier circuits 22f1 and 22f2 convert the output currents of the spot photometric sensor 17a and the peripheral photometric sensor 17b into logarithmically compressed voltage signals, respectively, and output the signals. It is input to the multiple integral control circuit 22g. Further, the control circuit 22g switches the switch SW1, takes in the analog signals output from the amplifier circuits 22f1 and 22f2, converts them into digital signals, and sequentially outputs the digital signals to the system controller 10.

22i is a circuit for causing the solid-state FFL image element 9 to start exposure in response to the "shaft open" signal, and for determining whether the exposure amount has become appropriate based on a detection signal from the photometric sensor 17a. The configuration of the circuit 22i for detecting proper exposure is such that the common terminal of the switch SWI is connected to the base of the transistor Q via the adder M1, the emitter of the transistor Q is grounded, and the collector is connected to the comparator CP.
is connected to the inverting input terminal of Further, the collector of the transistor Q is connected to the negative electrode of a capacitor C, and the positive electrode of the capacitor C is connected to a power supply terminal Vcc (not shown). Further, the power supply terminal V cc is connected to the positive pole of the constant voltage source B, and the negative pole of the identification voltage source B is connected to the normal input terminal of the comparator CP.

In addition, a switch SW2 is connected between the positive and negative electrodes of the capacitor C.
is connected, and the switch SW2 is controlled to open and close by the output of "Shutter open" from the system controller 10.

In the proper exposure detection circuit 221, when the switch SW2 is switched from "closed" to "open" by the above-mentioned "shutter open" signal, the capacitor C is charged by the collector current of the transistor Q, and the negative terminal of the capacitor C is charged. Potential (V
) decreases and becomes lower than the normal input terminal voltage (Vo) of the comparator CP, the output of the comparator CP is inverted to detect proper exposure, and this detection result is used as a signal to command the shutter to "close". It outputs to the system controller IO and the shutter control circuit 22n.

Next, the D/A conversion circuit 22h is connected to the system controller 1.
The brightness correction amount output from 0, for example, the above-mentioned ISO
It converts the adjustment amount for sensitivity variation adjustment from a digital signal to an analog signal, and the correction signal is sent to the adder M1.
The signal is input to the photometric sensor 17 and added to the light reception signal of the photometric sensor 17.

The battery check circuit 22J checks the capacity of the battery. Further, the flash trigger circuit 22.1 causes the flash circuit 18 to "flash light emission" in response to a flash light emission signal input from the system controller 10.
Outputs a trigger signal. In addition, the flash control circuit 2
2m is the flash circuit 1 by the control signal of "Start boosting"
8 (hereinafter referred to as charging of the flash circuit) to the main capacitor for light emission of flash circuit 18.
detects the charging state of the battery and outputs a charging completion signal to the system controller 10.

22n is a shutter control circuit that outputs a shutter opening/closing signal;
Shutter "open" and "close" control signals are output to the system controller 23 and the time control circuit 24 in response to the "open" control signal and the detection signal of the proper exposure detection circuit 221, or the forced termination signal from the system controller 10.

The time control circuit 24 is the same as the shutter control circuit 2.
The start and end of exposure of the solid-state image sensor 9 is controlled by the shutter "open" and "close" control signals inputted from the shutter 2n. The video processing control circuit 25 adjusts the video signal based on the gain correction amount input from the system controller 10 and the color temperature information input from the system controller 23, and also adjusts the video signal based on the field/frame recording signal input from the system controller 23. It also controls whether there are one or two recording tracks. Here, the details of the gain correction amount will be described later, but [Front light J
-1. OEv, -0,
5Ev, +0.5Ev, +1. This is the correction amount of OEv.

Further, 26 is a magnetic head and disk for recording, 27
is a spindle motor that rotates the disk 26. Additionally, the system controller 23 sends map information (
The system controller 10 sends information such as information indicating that the system controller 10 cannot accept switches such as empty track, recording end track information), recording in progress, head feeding in progress, etc.

Next, in FIG. 2 showing the system configuration, the operation of opening and closing the shutter will be explained focusing on the shutter control circuit 22n that outputs the shutter "open" and "closed" signals, the appropriate exposure detection circuit 22i, and the system controller 10. do.

First, when a shutter "open" signal "H" is output from the system controller 10, it is input to SW2, starts charging the capacitor C of the detection circuit 22i, and is also input to the EXOR circuit 31 of the shutter control circuit 22n. E
Since "H" is input to the input terminal at the other end of the XOR circuit 31, the EXOR circuit 31 outputs "H" to the time controller 24 and the system controller 23 to start solid-state imaging (exposure of the JA element 9). .Furthermore, the system controller 10 operates the shutter only when flashing is necessary.
At the same time as the "Open" signal is output, a time count for the flash emission time is started, and when the time count for the second flash emission time is completed, a flash trigger signal is output from the system controller 10 to the flash trigger circuit 221, and the flash emission is started. Start.

Next, when the detection circuit 221 detects proper exposure, a shutter "close" signal "H" is output from the comparator CP to the system controller 10 and the OR circuit 32. OR circuit 32
receives the above “H” output and sends “H” to the EXOR circuit 31.
The EXOR circuit 31 outputs "L" in response to the shutter "open" signal "H" inputted to the input terminal at the other end, and the system controller 23 and time controller 2
4 tells the end of exposure. In addition, if the timing at which the shutter "close" signal is output from the detection circuit 22i is later than a predetermined time (shake limit time), the system controller 10 outputs a forced termination signal "H" and exposes in the same manner as above. Communicate the end.

The system controller 10 determines the timing of outputting the shutter "open" signal, the timing of inputting the shutter "close" signal, the timing of outputting the forced end signal (shake limit time), and modes such as "frontlight" and "backlight". It calculates up/down of the gain (details will be shown later) and outputs it to the video processing control circuit 25.

28 is a communication line between the system controller 10 and the system controller 23;
For example, switch information signals such as Sl, S2, date, playback, field/frame, slide copier, negative copier, write or write inhibit, floppy detection, spindle motor ON/OFF, and current track number.

etc. control signals are sent.

Next, the photometry mode classification of subject brightness based on photometry information will be explained using Table 1. As shown in the table, the metering mode for subject brightness is divided into "bright" mode, which allows you to shoot using only natural light, and "dark" mode, which requires supplementary light from a flash. For each case of "Dark", there is a case of "Front light" where the brightness of the main subject on the shooting screen and the brightness of the sub-subject in the background is properly balanced, and a case of "Front light" where the brightness of the main subject on the shooting screen is relative to the brightness of the sub-subject in the background. It can be divided into four types: dark "backlight". Note that "front lighting" also includes back lighting.

In addition, for each of the four types of metering modes mentioned above, there is an "auto mode" that automatically determines whether or not the flash is necessary based on the metering results and selects the appropriate shooting method, and an "auto mode" that automatically determines whether or not the flash is necessary based on the metering results and selects the appropriate shooting method. There are three types of shooting modes: ``forced flash mode'', which fires the flash to take pictures, and ``flash prohibition mode'', which forcibly prohibits the flash from firing even when auxiliary light from the flash is required. handle. In addition, in the same table, [Forced flash J] and "Flash off" are respectively [Forced flash mode] and "Flash off mode".
"Flash" or "AE (light emission prohibited)" indicates the shooting mode selected by "Auto mode".

By the way, if we classify the shooting methods in the above-mentioned shooting modes based on whether or not a flash is required, there are two modes: natural light mode J, which uses only natural light without using the flash, and natural light mode J, which uses both natural light and flash light with the flash on. It is divided into "flash mode" for taking pictures. In the classification of photometry modes in Table 1 (described later), "flash off" and rAE (flash off)" are "natural light mode", and "forced flash" and "flash" are "flash mode".

Next, the photographing method of the photographing mode for each photometry mode of this embodiment will be explained.

(1) Regarding "Natural Light Mode"; In this mode, when shooting in "flash off mode" in the case of "bright backlight", the brightness of the sub-subject will be relatively bright compared to the brightness of the main subject. Therefore, when the main subject is photographed with an appropriate exposure amount, the sub-subject in the background will be photographed with brightness. For this reason, the photometered brightness of the main subject is corrected by +0°5Ev, and when the main subject is properly exposed, the exposure is stopped. By shooting in this way, the main subject will be exposed 0.5 times below the proper exposure.
Although the image is photographed at a low Ev, the background is prevented from being photographed extremely brightly, and the photograph as a whole is beautifully photographed.

Next, when shooting in "flash off mode" in the case of "dark backlight", the brightness of the secondary subject is relatively brighter than the brightness of the main subject, but the brightness of the secondary subject in the background is dark, so the main subject Even if the subject is photographed with the correct exposure, the secondary subject in the background will not be photographed too brightly.In this way, the metered brightness of the main subject is not corrected, and the main subject is properly exposed. Being photographed.

In addition, when shooting in "Flash Off Mode" in "Dark Front Light" and "Bright Front Light" in rAE (Flash Off), the balance between the brightness of the main subject and the sub-subject is relatively appropriate. In this case, the brightness of the entire shooting screen is bright and dark, so the average brightness (Bvs') is calculated by taking into account both the brightness of the main subject and the brightness of the sub-subject, and calculating the weighted average of the respective brightnesses. and then shoot so that the average brightness is the appropriate exposure. Note that when the brightness of the entire photographic screen is extremely low to the limit value of photometry, the average brightness is set such that the weight of the sub-subject's brightness is increased relative to the brightness of the main subject. Additionally, if the brightness of the shooting screen is significantly below the photometry limit, the release will be locked and shooting will not be possible.

(2) Regarding "flash mode": In this mode, "forced flash mode J" is considered to be the photographer's intention to take a picture using the flash light source regardless of the brightness of the main subject. Regardless of the mode classification, the flash fires with the shutter “open” control signal.
The main subject is then photographed with the correct exposure.

In addition, in the case of "bright backlight" (hereinafter referred to as "backlight flash mode"), the luminance of the metered subject is -1.
, OEv is applied to calculate the appropriate exposure time for the sub-subject, and the above correction f! If the APEX value of the exposure time obtained by subtracting i1゜OEv is Tv, then after shooting starts, the camera is exposed to natural light until the above exposure time Tv, and then the flash is fired and when the main subject becomes suitable, the exposure is stopped. Take a photo.

That is, the background is photographed using natural light with IEv brighter than appropriate, and then the main subject is photographed appropriately using flash light. By photographing in this manner, the main subject can be photographed clearly, and the sub-subject can be photographed brightly relative to the main subject, creating an atmosphere of backlight.

In addition, in the case of "dark backlight" and "dark forward light" (hereinafter referred to as "dark flash mode"), the main subject's brightness is +1. Apply the OEv correction, calculate the appropriate exposure time for the main subject, and set the above correction value 1. When the APEX value of the exposure time including OEv is Tv, after the start of shooting,
After exposure with natural light up to the above exposure time Tv, a flash is emitted and when the main subject becomes suitable, the exposure is stopped and photographed. That is, the main subject is photographed using natural light IEv darker than appropriate, and then the main subject is photographed appropriately using flash light.

By the way, in the above embodiment, the exposure time corresponding to the flash emission timing time is divided into "backlight flash mode" and "dark flash mode" and calculated by the system controller 10, and the exposure time is calculated at the same time as the solid-state image sensor 9 starts exposure. However, instead of calculating the flash firing timing time from advance photometry information, the solid-state image sensor 9 is used to measure the secondary subject in "backlight flash mode" and the main subject in "dark flash mode". Alternatively, direct light metering may be performed at the same time as the exposure to obtain the flash firing timing. That is,
In "backlight flash mode", the sub-subject brightness is directly measured at the same time as the exposure of the solid-state image sensor 9 starts, and 1. When OEv increases, fire the flash,
Exposure ends when the main subject becomes suitable. Also,
In the "dark flash mode", the brightness of the main subject is directly measured at the same time as the exposure of the solid-state image sensor 9 starts, and 1. The flash may be emitted when the OEv is low, and the exposure may be ended when the main subject becomes suitable.

This concludes the explanation of how to shoot in each shooting mode, and next,
A description will be given of dividing the photographing mode into modes based on the brightness of the subject detected by the photometric sensor 17.

The photometric sensor 17 is composed of two types of photometric sensors: a photometric sensor 17a that spot-meters the brightness at the center of the photographic screen, and a photometric sensor 17b that measures the brightness around the photographic screen. For example, when photographing a person, the main subject, the person, is often placed in the center of the shooting screen, and the background, which is the sub-subject, is often placed around the periphery of the shooting screen. This method measures the brightness and the brightness of the sub-subject separately.

By the way, the brightness at the center of the photographic screen measured by the photometric sensor 17a (hereinafter referred to as center brightness) is Bvt, and the brightness around the photographic screen measured by the photometric sensor 17b (
If the brightness of the main subject (hereinafter referred to as peripheral brightness) is By2, the brightness of the main subject is Bvs, and the brightness of the sub-subject is BvA, then the photometric value Bv2 can be used as the brightness BvA of the sub-subject such as the background, but the photometric value Bv1 is the brightness B of the main subject
It is known that when used as vs, an error occurs. For example, if the main subject is small relative to the shooting screen and is backlit, the background light will wrap around the main subject, the photometric value Bv1 will be larger than the main subject brightness Bvs, and the shooting lens may be a zoom lens. In this case, if the ratio of the size of the main subject to the photographic screen is arbitrarily changed by zooming, the error between the photometric value Bv1 and the main subject brightness Bvs will differ depending on the ratio. Therefore, it is necessary to correct the photometric value Bvf to obtain the main subject brightness Bvs according to the ratio of the size of the main subject to the photographic screen and the difference in brightness between the main subject and the sub-subject. That is,
When this correction amount is α, the main subject brightness Bvs is expressed as Bvs=Bvl −a −·−■. Note that the unit of subject brightness is expressed in Ev value.

Table 2 (described later) is an α muff representing the correction amount α. In the same table, β is the photographing magnification that indicates the size of the subject relative to the photographic screen, and ΔBv is the difference between the peripheral brightness Bv2 and the central brightness Bvl, that is, ΔBv=Bv2−Bv
It shows t. As shown in the table, as β becomes smaller, the ratio of the size of the main subject to the shooting screen becomes smaller, and the amount of light that wraps around from surrounding objects to the photometric sensor 17a increases, so the value of the correction amount α becomes larger. It has become.

Furthermore, as ΔBv increases, the brightness of surrounding objects becomes brighter than that of the main object, and the backlight becomes stronger, so the amount of light that wraps around from the surrounding objects to the photometric sensor 17a increases, so the value of the correction amount α becomes larger. There is. However, when β is smaller than 1/1()O, the ratio of the size of the main subject to the shooting screen is so small that it cannot be considered as the main subject on the shooting screen, so do not include the correction amount α. ing.

Furthermore, when ΔBv is 2.75 or more, it can be considered that the amount of light that wraps around from the secondary subject to the photometric sensor 17a is small, that is, the main subject is relatively accurately photometered in strong backlight, and Since the main subject is considered to be relatively large, the value of the correction amount α is set to a small value of 1- to take advantage of the shooting conditions.

Here, the above main subject brightness Bvs and sub-subject brightness Bv
The mode classification of "frontlight" and "backlight J" by A will be explained.

Luminance difference (B
vA-Bvs) is ΔBv', when the sub-subject brightness is larger than a certain value (δ) compared to the main subject brightness, that is, when ΔBv')δ, the sub-subject is higher than the main subject. Set it as "backlight" which is too bright, and set ΔBv'≦δ
In the case of , the brightness of the main subject and sub-subject is well balanced.

Table 3 (described later) shows the δ mag giving the above constant value δ. The δ values in the table were obtained through actual photography, and the δ values vary in three levels depending on the brightness of the main subject. This is because as the brightness increases, the amount of light that wraps around from the periphery to the center increases, making it difficult to detect backlight.
Table constants are selected.

Next, the classification of flash emission modes will be explained.

Exposure time is long, and the brightness is at the limit where photographers can experience camera shake (
Hereinafter referred to as camera shake limit brightness) is Bvt-1,
When the overall brightness of the shooting screen is lower than the camera shake limit brightness BvH, the "Franche mode" is set in which the flash is fired and the photo is taken. Therefore, a weighted average value Bvs' of the main subject brightness Bvs and the sub-subject brightness BvA, taking into account their respective brightnesses, is used as the average brightness of the entire photographic screen. In the case of “Front light”, Bvs
' is given by Bvs' = Bvs/4 + (3・BvA )/4, and when Bvs'≧Bv)I, the front light flash mode is set around rJ, and when Bvs'<BvH, the entire shooting screen is dark, so , [Dark flash mode].

In addition, in the case of "backlight", the sub-subject brightness is higher than the main subject brightness, so the value (BvA -
δ) will be used.

That is, when BvA-δ≧BvH, the background is bright;
Since the main subject will be dark due to backlighting, use the "backlight flash mode" to fire the flash, and BvA −-δ<
When B v fl, Bvs≦BvA−δ<B v
From If, even though it is backlit, the entire shooting screen is dark, so we set it to "dark flash mode".

In addition, if the center brightness Bv1 is low enough to reach the photometric limit value of the photometric sensor 7a, the reliability of the photometric value is low. Weighted average value Bvs with increased weight
' to process as [low brightness processing mode]. That is, Bvs = Bvs/8+ <7 · Bv
A) Using Bvs′ calculated by /8, processing is performed as “dark flash ζ mode”.

Below are "Natural light mode" and "Dark flash mode"
, "backlight flash mode", and "forced flash mode", the control of the exposure time of the solid-state image sensor 9 and the control of the flash light emission timing time will be explained.

FIG. 3 shows an example of the exposure time of the solid-state image sensor 9 and the timing time of flash emission. Same T v I
t In the figure, tH (=2 > is the limit exposure time C that causes camera shake, the camera shake limit shutter speed), and is changed according to the output of the zoom encoder, that is, the value of the focal length Mf of the lens.

tH (=2 ”X) is the i-light M of Ii 1 body 111 element 9
The highest shutter speed that can be controlled between
It shows the time when H is divided into two. In addition, T v tA (=2 > is the shutter start signal and the solid state machine f
! This is the delay time from when the LC element 9 starts exposure to when the flash starts emitting light, and is called "flash mode".
Then, after being exposed to natural light for a predetermined time t^, a flash is emitted. Furthermore, tF indicates the time during which the flash is emitting light, and ts indicates the time at which appropriate exposure is achieved.

(1) [Natural light mode] will be explained.

``Natural light mode J is divided into three types of shooting methods, which will be explained below, depending on the brightness of the main subject.

■When the brightness of the main subject is very bright and the proper exposure is reached within the time of the maximum shutter speed tH.

Exposure is carried out up to the maximum shutter speed time tH, and overexposure is carried out beyond the time ts at which proper exposure is obtained (70-ts), so the captured image is reduced in gain by the image processing control circuit 25. In this way, overexposure is corrected.

By the way, since the exposure time of tH/2 corresponds to overexposure of IEv, the system controller 10 adjusts the gain correction amount separately for ts≦to (to==tH/2> and tH>ts>to). The image processing control circuit 25
It is output to. In other words, if ts≦to, the excessive exposure time (tH-ts) will be shorter than tH/2, so
Constant gain1. Decrease OEv, t H > t s
> to, the excessive exposure time (tH-ts) is longer than tH/2, so the constant gain of 0.5Ev is reduced.

0 When proper exposure can be obtained in a shorter time than the camera shake limit shutter speed tH.

This is a case where proper photography is performed using only normal natural light.
The photographed video is recorded without exposure correction by the video processing control circuit 25.

■ Time ts when the brightness of the main subject is dark and reaches the appropriate exposure
exceeds the camera shake limit shutter speed tH.

Camera shake limit shutter speed tH to prevent camera shake
Exposure is forcibly stopped at , and the gain of the image photographed by the image processing control circuit 25 is increased by 0.5 Ev to correct the underexposure.

(2) “Dark flash mode” will be explained.

In the "dark flash mode", after the solid-state image sensor 9 starts exposure, the main subject in the shooting screen is set to 1. O
Until the time when Ev reaches a low value (this time is defined as tA),
exposed by natural light, then a flash is fired,
Exposure is stopped when the main subject becomes suitable.

This "dark flash mode" is divided into three types of shooting methods depending on the brightness of the main subject. In other words, ■When the proper exposure is reached while the flash is firing.

■When the proper exposure is reached within the camera shake limit time 11+ after the flash fires.

■If the time tS at which proper exposure is reached after flash emission exceeds the camera shake limit 2 hours t11 (note that tA-tH
The flash is emitted at , and the flash is emitted for a light emission time of t (including cases where proper exposure cannot be obtained after the flash is finished).

In the case of (1) and (2) above, exposure is stopped when proper exposure is obtained, and the photographed image is recorded without exposure correction by the image processing control circuit 25. In case (2), when the camera shake limit time t11 has elapsed, exposure is forcibly stopped to prevent camera shake, and the underexposure is transferred to the video processing control circuit 2.
5, the gain is increased by 0.5Ev and corrected.

(3) [Backlight flash mode] will be explained.

In "backlight flash mode", the time from when the solid-state image sensor 9 starts exposure until the secondary subject in the background in the shooting screen has a value IEv higher than the appropriate exposure (this time is set as ta)
After that, the flash is emitted, and when the main subject is properly exposed, the exposure is stopped.

In this "backlight flash mode", there are two types of shooting methods depending on the brightness of the subject. In other words, ■When the proper exposure is reached while the flash is firing.

■When the proper exposure is not reached even after the flash emission time t[ elapses after the flash is emitted.

In the case of ■ above, stop the exposure when the proper exposure is obtained,
The photographed video is recorded without exposure correction by the video processing control circuit 25. In the case of (2), since the subject with a bright background is photographed in [backlight flash mode], if the main subject is exposed beyond the flash emission time tF until the time ts when the main subject is properly exposed, the natural light after the flash emission will be Since the secondary subject becomes excessively bright due to the exposure, the exposure is forcibly stopped after the flash emission time tF, and the exposure is not corrected by the image processing control circuit 25 for the photographed image.

Next, in the above-mentioned "backlight flash mode" and when the distance to the main subject exceeds the limit that the flash light can reach, the solid-state image sensor 9 starts exposure, and then the above-mentioned flutter, 2. It is exposed to natural light until a time that is 1°OEv added to the light emission delay time tA (this time is set as tA'=t^/2), then a flash is emitted, and after the flash is emitted, the exposure is stopped. Similar to the above-mentioned "backlight flash mode J", the time t when the main subject is properly exposed
If s exceeds the flash emission time t[, the exposure is forcibly stopped after the flash emission time tF, and the image processing control circuit 25 sets the gain to 1. Exposure is corrected by increasing OEv. In other words, in the "backlight flash mode" where the distance to the main subject exceeds the limit that the flash light can reach, the flash does not work effectively as auxiliary light for the main subject, so the exposure time using natural light is Shorten the exposure time using natural light by half to make the overall IEv darker, then fire the flash, forcefully stop the exposure after the flash is finished, and increase the overall gain at the captured image stage. IEv
It is something that increases. Then, in this way, the overall IEv is lowered so that the difference in brightness between the main subject and the sub-subject is smaller than the actual brightness difference, and the IEv is corrected to be higher overall at the video stage. Because there are
The main subject can be photographed clearly, and the balance of brightness between the main subject and the sub-subject can also be adjusted appropriately. Here, the flash emission timing time L
A is the time from the start of exposure of the solid-state image sensor 9 until the flash is emitted, and is calculated by the system controller 10 based on the photometered main and sub-object brightnesses.

(4) “Forced light emission mode” will be explained.

In the "forced flash mode", a flash is emitted when the maximum shutter speed tH has elapsed after starting exposure, and the exposure is stopped when the main subject is properly exposed.

In addition, if the time required for the main subject to be properly exposed exceeds the camera shake limit shutter speed tl+, the exposure will be forcibly stopped when the camera shake limit shutter speed t11 has elapsed to prevent camera shake, and the underexposure will be reflected in the image. The processing control circuit 25 increases the video gain by 0.5 Ev to correct it.

Next, a sequence for controlling the camera section of the system controller 10 in the electronic camera of this embodiment will be described.

First, the main routine will be explained using the flowchart shown in FIG. In the first state when the battery is inserted into the camera, the system controller 10 is reset to the initial state (#5), executes the initial setting subroutine,
Initial settings of the system controller 10 are performed (#1
0). Next, in steps #15 to #30, it is checked whether the camera is in the shooting state. In other words, whether the power supply battery is turned on (#15), whether "playback mode" is not selected with the playback switch 310 (#20), whether the deck lid is open (#25), or whether the deck lid is open. Check at each step whether the state has changed from "open" to "closed"(#30). If the battery is not inserted in each of the above steps, a "battery removal" subroutine is executed (#200). If "Playback Mode" is selected, execute the "Playback" subroutine (
#210). When the deck lid is open, the
Execute the subroutine "Prohibit playback" to prohibit both recording and playback operations (#220>. When a floppy disk for recording is inserted and the state of the deck changes from "open" to "closed" executes the "Initial Load" subroutine, checks the information on the floppy disk, and loads that information into the system controller 10 (
#500).

Next, check whether the main switch SO is turned on (#35). If the main switch SO is OFF, shooting will not begin, so proceed to #110, set the photographing lens 1 to the initial position, and turn off the display on the LCD display circuit 21a (#115). If the flash circuit 18 is If the voltage is being increased for charging, proceed to #145, stop the voltage increase, turn off the flash charging LED display (red) in the viewfinder (#150), and enter the HALT state (#160). ). In the HALT state, the sequence execution of the system controller 10 is paused, and the settings of the switches 21 are checked for changes at regular intervals (#1
70) If there is no change in the settings, the HALT state is continued, and if there is a change in the settings, the process returns to #15.

If the main switch SO is turned on, the same switch S
Confirm that O changes from OFF to ON (#40
). When the main switch SO is turned on for the first time,
In order to charge the flash circuit 18, set the "boosting required" flag from Sera 1 to #45), and if it is not the first time it is turned ON, skip #45 and display on the LCD display circuit 21a (#50). ). The LCD display circuit 21a displays field/frame and single/self-timer mode selection, a counter for the number of shots, a battery warning, a recording mode, etc.

Next, check whether the start switch S1 of AE and AP is ON (#55). If the switch S1 is ON, it indicates that the switch S1 is kept pressed.
Confirm the presence or absence of the "Press and hold" flag (#60). This will perform AE and AF again when the switch S1 is pressed again, and if the switch S1 is kept pressed, the AE and AF will be performed again.
E. This is because AF is not performed. If this flag is not set, execute the rsIJ subroutine and
Perform E (auto exposure) and AP (auto focus) (#80
0). Switch S1 is OFF or “
If the "keep pushing" flag is set, then it is checked whether there is a change in each mode of single/self-timer, field/frame, and date information switching (#65).

That is, a single/self-timer mode changeover switch S15, a field/frame mode changeover switch 31
1. When none of the switches in date information mode switching 55-1 are held down, switch 315,
S11.55-1 is checked sequentially to confirm whether or not there is a mode change.
If N, execute the "mode change" subroutine in #230.
If it is ON, the "date change" subroutine of #240 is executed. If the field/frame mode changeover switch S11 is ON in #80, [
Execute the “field/frame change” subroutine,
If there is no change in each mode, check if the date has been corrected (#85). If any switch is held down, there is no mode change, so do not check each mode changeover switch ( Skip #70 to #80) and proceed to date correction (#85). If the date correction switch 55-2 is pressed, the "date correction" subroutine of #260 is executed. If the date information is not corrected, next check whether flashing is necessary (#90~#
105), this is for setting a flag in order to identify whether or not boosting the voltage for charging the flash circuit 18 is necessary depending on whether or not flash is necessary. If the "forced flash" switch 313 is pressed in #90, "boost required"
If the "light emission prohibition" switch 314 is pressed in #100, the "boosting not required" flag is set (#105).

Next, check whether the "boost required" flag is set, and if it is set, start boosting if charging is not completed.
1 LED display in the viewfinder when the flash is charging b (
red) (#120 to #135). Then, the boosting time is confirmed (#140), and when the boosting is completed within a predetermined time, the process returns to #15. Here, if the boosting is not completed within the predetermined time, a battery check is performed (#270), and if the "boosting required" flag is not set in #120, or charging has already been completed in #125. If completed, the process proceeds to steps #145 to #170 described above and enters the HALT state. Note that when each subroutine ends, the process returns to step #15(A).

Next, the "initial load" subroutine of #500 will be explained using FIG.

First, execute the battery check subroutine to check the battery capacity ($505). Next, it is checked whether a floppy disk is inserted (#510), and if it is not inserted, the "release disabled" subroutine of #700 is executed to prohibit driving of anything other than the mirror 3 and photographing lens 1. If inserted, DC/DC is used to supply power to the spindle motor 27 and video processing control circuit 25.
Converter 12 is activated (#515).

Next, the spindle motor 27 and the video processing control circuit 25 are driven (#520) to read the contents written on the floppy disk 26, that is, 50 tracks of data, and create a map. In addition, the LCD display circuit 1
9b displays the track that is counting up, indicating that the contents of the floppy disk 26 are being checked (#525).

Next, check whether the "playback mode" is selected with the playback switch 310 (#530), and if the "playback mode" is selected, execute steps #535 to #545 to enter the "playback mode". In other words, check whether there is a recording prohibition claw on the floppy disk 26 (#535), and if there is no claw, recording will be prohibited, so set the "erasure prohibited" flag #540), and if there is a claw, recording will be allowed. Therefore, r can be deleted.”
flag (#545), and proceeds to the "playback mode" subroutine in #210. If "playback mode" is not selected in #530, the floppy disk 26
Check whether there is a recording prohibition claw #550), and if there is no claw, display "recording prohibition" for the inserted floppy disk 26 on the LCD display circuit 19b #555).
Stop the recording operation (#570). If there is a claw, check whether there is an empty track on the floppy disk 26 (#560). If there is no empty track, the LCD display circuit 19b indicates that there is no empty track. Please display #56
5) Stop the recording operation in the same way as without claws (#
570). If there is an empty track, the process proceeds to #600, the head is driven to an unrecorded track based on the map information obtained in #525, and then the process returns to #15 of the main routine.

Next, #800 “SIJ” that executes AE and AF etc.
The subroutine will be explained using FIG. “S.
1'' subroutine sequence executes AP, executes AE after focusing on the subject, prepares the flash to emit light if necessary, and enters release. First, #805 to #835 before entering AF
Battery check, power supply, system controller 23
, white balance, etc. In other words, when boosting the voltage of the flash circuit 18, stop the boost (#805) and perform a battery check (#81).
0), to set the white balance (WB) to a specific color temperature for daylight #815), and to supply power to the solid-state image sensor 9, video processing control circuit 25, spindle motor 27, and circuit for that song. , start the DC/DCC/function (#820), and the system controller 23
(CPU 2) is reset (#825), and the color temperature sensor circuit 20 is activated (#830).

Next, execute the AF subroutine #1200 (described later), perform a focusing operation on the subject (#835), and if the reliability of the focus detection result is low due to low contrast and the focus is incomplete, , an out-of-focus display is performed in the finder, and the process returns to #15 of the main routine (#840 to #850).

When focusing is completed in #84o, check whether the self-timer mode is selected (#855); if the self-timer mode is not selected, start the spindle motor 27 to drive the floppy disk 26. let me,
Prepare for recording (#860). If the self-timer mode is selected, there is no need to drive the spindle motor until the release, so #860 is skipped and the color temperature sensor circuit 20 captures the subject. The color temperature information of the light source is read from the color measurement information (#865), and it is detected whether the light source is a fluorescent lamp or tungsten light (#870).
). When the light source is a fluorescent lamp or tungsten light, a "flash required" flag is set in order to emit a flash to take a picture (#875).

This is because fluorescent lamps or tungsten light have a different color temperature distribution than sunlight, and it is better to take pictures with flash light that is similar to sunlight, so the flash is automatically activated. When the light source is not a fluorescent lamp or tungsten light, the "photometry" subroutine of #1500, which will be described later, is executed without setting the "flash required" flag, and the brightness of the subject is photometered (#880).

Next, when the metering of the subject brightness is completed in #880, #88
In steps 5 to #905, various flags are checked to confirm whether or not a flash is necessary. First, check whether the "Flash Required" flag is set (#885), and whether the flag is set or not.
Alternatively, if the flag is not set but the "forced light emission mode" is selected (#890), then it is checked whether the "light emission prohibition mode" is selected (#895).

If "Flash prohibition mode" is not selected, it is the flash mode, so please check whether "Forced flash mode J" in #890 is selected (#905), and if it is selected, set the "Forced flash mode" flag. Set it (#910
), check the charging state of the flash circuit 18 (#
915>, the flag for "forced flash mode" is set in step #910 to identify the difference in flash light emission timing between "forced flash" and auto mode.

Next, if charging of the flash circuit 18 is completed in #915, stop boosting the voltage for charging (#920), #8
If the spindle motor 27 is not started at 60, the motor 27 is started and preparations are made for recording to the floppy disk 26 (#925), and the LF and D displays 19a (green) indicate that the flash is fully charged in the viewfinder. (#9
30), proceed to #970 and check the release switch S2. If charging of the flash circuit 18 is not completed in #915, start boosting the voltage for charging (#935)
, if the spindle motor 27 is started in #860,
Stop the drive (#940), and display the LED display 19a (red) indicating that the flash is charging in the viewfinder (#9
45), the reason why the drive of the spindle motor 27 is stopped at #940 is to avoid unnecessary current consumption since there is no need to drive the spindle motor 27 during preparation for flash emission.

Next, check the state of switch S1 (#950),
If it is 0FFt, return to #15 of the main routine,
If it turns ON, check switch S2 #95
5) If switch S2 is ON, return to #15 of the main routine and select L while the flash is charging in the viewfinder.
Turn off the ED display 19a (red) (#965)
1. Proceed to #920 to #930 described in h.

By the way, if "forced flash mode" is not selected in #890, the flash will not fire, so just press #
Proceeding to 970, the release switch S2 is checked. Also, since the flash does not fire even when "flash prohibition mode" is selected in #895, the flash fire is prohibited, giving priority to "forced flash" or auto mode, and #8
Change the color temperature for daylight set in #15 to #865
Based on the input colorimetric information, the temperature sensor circuit 20 changes the signal to a signal for adjusting the color balance of the photographed image and outputs it (#900), and then the process proceeds to #970.

Next, check the release switch S2 (#970), and if the switch S2 is OFF, switch 5O1S
1 is confirmed (#1030 to #1035), and if any of them is OFF, the process returns to #15 of the main routine. If both switches 5O1S1 are ON, check whether the deck lid is open or closed (#1040). If the deck lid is closed, return to #865; if it is open, check #22
Executes subroutine 0 and prohibits all recording and playback operations.

If release switch S2 is turned on in #970,
Make sure the self-timer mode is selected #9
75) If the self-timer mode is selected, the timing time for self-timer photography is counted, the light emitting element 14 is blinked (#980), and the spindle motor 27 is activated.
Start up and prepare for recording on the floppy disk 26 (#985), and after 100m5 has passed, flip up the main mirror 3 and release the light shielding to the solid-state image sensor 9 (#99
0), if the self-timer mode is not selected, skip steps #980 to #985, raise the main mirror 3, and move the solid-state rim element 9 and image processing control circuit 2.
5 (#995), and after counting the power up time (approximately 100m5) of the video processing control circuit 25 (#1000), execute the "release" subroutine of #2000, which will be described later, and release the solid @ @ Motoko 9
Exposure is performed (#1005). Next, after the exposure of the solid-state image sensor 9 is completed, the captured image is recorded on the floppy disk 26, and the driving of the color temperature sensor circuit 20, video processing control circuit 25, and solid-state image sensor 9 is stopped (
#1015) and lower the main mirror 3 (#1020
), execute the "head feed" subroutine (designates the next track based on the map information), #1025),
Return to #15 of the main routine.

As explained above, in this embodiment, in the "Sl" subroutine sequence, in order to accurately measure the brightness of the main subject and the brightness of the sub-subject, AF is executed first and the subject is accurately focused. The photometry (AF,') calculation is then executed.

By doing this, in the "photometry" subroutine sequence described later based on accurate photometry data,
It is possible to classify appropriate photometry modes and calculate accurate flash firing timing. Also, in self-timer mode, to avoid unnecessary current consumption,
The spindle motor 27 is not activated until a predetermined period of time has elapsed. In addition, when using fluorescent light or tungsten light as the light source, the color temperature setting is fixed to sunlight (flash light source), so the flash is automatically emitted to take a picture, and the flash prohibition switch S14 is set. When "Light off mode" is selected, the color temperature is automatically adjusted to the color temperature of fluorescent light or tungsten light (AWB).
I try to do that.

Next, r of #1200 (#835 above) to execute AF.
The AFJ subroutine will be explained using FIG. 7.

First, turn on the power to the focus detection sensor 7 (CCD line sensor #1205), then discharge unnecessary charges accumulated in the focus detection sensor and set it to the initial state (#1
210), start charge accumulation of the focus detection sensor (#1
215>. Thereafter, the system waits until the interlaced signal lNTl that indicates the end time of charge accumulation of the focus detection sensor is input (#1220), and the interwoven signal lNTl
When detected (#1225), the accumulated charges of the focus detection sensor 7 are transferred to the analog shift register, and the accumulated charges are output from the shift register one pixel at a time, A/D converted, and sequentially input to the system controller 10 ( #123
0).

Next, the system controller 10 detects the defocus measurement from the data imported #1235), determines the reliability of the defocus measurement #1240),
If it is unreliable due to low contrast,
Execute the "low contrast" processing subroutine #
1325), displays the out-of-focus state (#1330), and returns to the main routine (#1320).If it is not unreliable due to low contrast, check whether the subject is accurately focused.#1245 ), if it is in focus, the current stop position information is obtained from the previous stop position information of the photographing lens 1 and the current movement amount information, and based on this information, the current stop position is determined according to the focal length f at that time. The photographing distance is determined using the conversion coefficient, and the photographing magnification β is calculated from this photographing distance and the focal length f (#1305), and the focus LED 19a (green) in the finder is displayed (#1305).
1310), turn off the clutch circuit 13, and switch the connection to the motor M from the photographing lens 1 to the main mirror 3 (#1
315), return to the main routine (#1320
), and if it is not in focus in #1245, it will be focused in the following steps.

First, the lens extension amount conversion coefficient K is read from the ROM in the system controller 10 based on the current focal pressure ll1f from the zoom encoder switch S12 (#12
50) Multiply the defocus scale by the conversion coefficient K to determine the number of pulses N (=
KXD) (#1255>0 Next, put the calculated number of pulses N into the "counter" in the system controller that monitors the rotation amount of the motor (#1260), turn on the clutch circuit 13, and connect it to the motor. Switch from main mirror 3 to photographing lens 1 (#1265), and then switch to photographing lens 1.
starts driving (#1270).

Next, make it interruptible by the "counter"#
1275), wait until the counter value reaches -0 and a counter interrupt occurs #1280), and with the counter interrupt occurring (#1285), stop driving the photographing lens 1 and focus (#1290) ), and in order to confirm the in-focus state, the charge accumulation of the focus detection sensor 7 is started again (#1295), and the inter-raft signal lNTl is output.
Wait until input (#1300), and then enter #1.
Return to #225 and perform focus confirmation processing.0 If focus is incomplete during focus confirmation processing, go back to #1245 to #125.
0 and repeats the routine from #1250 to #1300 until focus is achieved.

Next, the "photometry" subroutine of #1500 (above 8880) will be explained using FIG. 8(a). Note that in the figure, the unit used for calculation is the APEX value.

First, calculate the ISO sensitivity correction, that is, calculate the correction 130 sensitivity 5v (-3VO+7) from the standard ISO sensitivity Svo of the solid-state image sensor 9 and the imaging sensitivity variation correction amount γ #1503), and then the photometric sensor 17a , 17b start measuring the brightness Bv1 (spot photometric value) at the center of the photographic screen and the brightness Bv2 <average photometric value) around the photographic screen (#1505), and then the photometric sensor 17a
Start converting the brightness analog signal photometered by 17b into a digital signal by the double integration circuit 22g.$1
510), then check whether the A/D conversion of the photometered luminance has been completed #1515), and if it is not completed, wait until it is completed, and when it is completed, it is converted to a digital signal to the system controller 10. Input photometric data (#1520).

Next, check whether the AP-AE rotation is completed (#
1525). If AF'-AE is not locked, steps #1530 to #1545 are executed to obtain the brightness difference ΔBv between the two peripheral brightness Bv2 and the center brightness Bvf and the main subject brightness Bvs. In other words, check whether Bvl exceeds 11 (#1530); if it exceeds 11, the center brightness is too high, so fix Bv1 = 11 (#1535); if it is less than 11, use the same Bvl, Ambient brightness Bv2
Calculate the brightness difference ΔBv=Bv2-Bvl between the center brightness Bv1 and the center brightness Bv1 (#1540), then subtract the correction amount α shown in Table 1 from the center brightness Bv1 to obtain the main subject brightness Bvs (=
Bvl-a) (#1545). When AP-AE is locked, the brightness difference ΔBv and main subject brightness Bvs have already been calculated, so 81530~#
Skip 1545 and proceed to #1550, which will be described later. Note that AP-AE is set to switch S1 in the main routine.
is closed (#55), and when the photometry (AE>calculation subroutine is entered for the first time (enter #1500 at #880 of subroutine "Sl"), the lock is not applied and the steps from #1525 to #1530 are entered. Proceed to subroutine "
Return from SIJ #1040 to #865 and then #880 again
It is locked for the first time when #1525 is entered.

Next, check if the peripheral brightness Bv2 is over 10.#
1.550), if Bv2 exceeds 10, the peripheral brightness is too high, so fix Bv2 = 10 #1555)
, 10 or less, Bv2 is used as it is and is set as the sub-subject brightness BvA (#1560). Next, the central brightness Bv
1 is the low brightness close to the photometric limit of the photometric sensor 17a (#1565), and if the low brightness is close to the photometric limit, the average brightness of the entire shooting screen for low brightness processing BvS
Calculate ' using the following formula (#1595) and proceed to #1600, that is, Bvs 7 ・ BvA Bvs' = 10 If the brightness is not low, calculate the reference value δ for backlight judgment from Table 2 and Bvs (#1570) , then the brightness difference ΔBv' (=BvA−
Bvs) and the determination reference value δ obtained in #1570 are compared (#1575). Here, if ΔBv')δ,
It is determined that there is backlight and the message “Please set the backlight J flag” #158
0), set the average brightness Bvs' for backlight processing to Bvs (#1590), proceed to #1600, and set ΔBv'≦
If it is δ, it is determined that it is "frontlight", and the average brightness Bvs' for frontlight processing is calculated using the following formula (#1585), and #
Proceed to 1600.

Bvs3-BvABv6'=
+Next, #1600 to #1615
First, check whether the "backlight" flag is set (#1600), and if the flag is not set (in the case of "frontlight mode"), select #1.
585 Mana compares the average brightness Bvs' of the entire shooting screen obtained in #1595 and the camera shake limit brightness Bvtl, and divides the mode into "flash mode" and "natural light mode"(#1605), if Bvs'≧BvH. For example, next, it is determined whether the flash necessity flag is set (#1606). If the flag is set here, it indicates that the illumination light source is not sunlight but artificial light such as fluorescent light or tungsten light, and that it was set in #875 in Figure 6, indicating that the Proceed to flash mode routine 2. On the other hand, if the flag is not set, proceed to $1620 of the "natural light mode" routine ■. If Bvs'<Bvll, proceed to # of the "dark flash mode" routine ■ Proceed to 1675. If the "backlight" flag is set (in the case of "backlight"), the brightness (Bv
A-δ) and camera shake limit brightness Bvtl #161
0), if (BvA-δ)≧BvH, set the “transparent” flag indicating backlight on a bright background (#1
615), "Backlight flash mode" routine ■#
Proceed to step 1800. If (BvA-δ)<BvH, it is backlighting in a dark background, so proceed to step #1675 of the "dark flash mode" routine (2).

Next, the "natural light mode" will be explained.

First, check whether the "forced flash" flag is set (#1620). If the flag is not set, then check whether the "transparent" flag is set (#1625), If the J flag is not set, set the control Bv value Bv■ to the average brightness Bvs'(#1630), and set the correction amount ΔEvH when metering the main subject brightness to the die reflex 1- to O (#1630). 1635
), if the "transparent" flag is set in #1625, the background is brightly backlit, so the control Bv value BvT is the value obtained by correcting the main subject brightness Bvs by +0.5, that is, B
Set vT-Bvs+0.5 (#1640), and set the above correction amount ΔEvHL to (0,5-(Z)) (#1
645), where α is the correction amount shown in Table 1, and its value changes depending on the imaging magnification β.

Next, control Bv value BvT and minimum brightness Bv that can be photographed
Compare #1650), if BvT≦Bvl-, the shooting screen is too dark, so set the "shooting not possible" flag #1660), and display that shooting is not allowed in the viewfinder (#1665). Execute the “release lock” subroutine to prohibit shooting (#1670), Bv
If T > BvL, set the flash unnecessary flag #1655) and return to the main routine (#
1795).

Further, if the "forced light emission" flag is set in #1620, it is the flash mode, and the process proceeds to #1675 of the "dark flash mode" routine (2).

Next, the "dark flash mode" routine (3) will be explained.

First, check whether the "flash prohibition" flag is set (#1675). If the flag is set, it means that you are shooting in natural light, so proceed to #1625 of "Natural Light Mode J Routine ■".The flag is set. If not,
Brightness with main subject brightness Bvs corrected by +1.0 (Bvs+
1> and the camera shake limit brightness BvH #1680),
The setting of control Bvft is changed depending on the brightness of the main subject. In other words, if Bvs+1≧BvH, set the control Bv [brightness (Bvs-)-1 which is the main subject brightness Bvs corrected by +1°0 to BvT) #168
5) If , Bvs+1<Bv)l, the main subject brightness is lower than the camera shake limit brightness, so the control Bv value BvT is fixed to the camera shake limit brightness Bvtl (#1690).

Next, the correction amount ΔEvF of the exposure amount due to flash emission
Assuming that the coefficient K added to L is O, #1695), the value of the photographic magnification β is classified into three types (#1700), and the correction amount ΔEv of the exposure amount due to flash emission is calculated for each of the three types (#1700).
Set FL (#1705 to #1715). In other words, if β>(1/25), the correction amount ΔEvF is set to 0.
#1705), (1/25)≧β>(115
5), set the correction amount ΔEvF to (0,5-K) #1710), and if (1155)≧β, set the correction amount ΔEvFL of the exposure amount due to flash emission to (1,
0-K) (#1715), this is the imaging magnification β
This is a correction because the size of the main subject on the photographic screen changes and the amount of exposure due to flash emission also changes.

Next, the above correction amount ΔE is added to the maximum light emission amount Iv of the flash.
Flash light emission amount Iv (-1v+Δ
EvFL), and then calculate the aperture value A using the following formula from the above Iv', film sensitivity Sv, and subject distance information Dv.
Calculate vD (#1720), that is, AvO=I v' +5v-Dv = I v+5v-Dv+ΔEvF Next, calculate the aperture value AvD obtained in #1720 and the aperture value Avoz corresponding to the focal length at that time. Compare and determine whether the distance to the subject exceeds the limit that the flash light can reach (
#1725), if AvD > Avoz, a warning is issued to indicate that the distance to the subject exceeds the limit that the flash light can reach (#1730), and a flag for "fast formation" is set. (#1735), aperture @A
v Set D to Avoz (#1740), AvD
If ≦Avoz, do nothing and set the aperture r.
Set iA v D to Avoz (#1740).

Next, the brightness B v H (= T v H + A v
DSv) and the control B vliiB vT set in #1685 or #1690 (#1745),
If BvT≦BvH, proceed directly to #1765,
The flash light emission timing time Tv is calculated using the above control B v lii B v T. BvT>Bv
If it is H, check whether the "transparent" flag is set (#1750), and if the flag is not set,
Proceed to #1765, and if the flag is set, control B v MB v T (T v H + AvD - 3v)
(#1755), main subject brightness Bvs and #1
Control BV value BvT (=TvH+A
vD-8v) and #1760), Bvs≦Bv
If T, the process proceeds to #1765, and the flash light emission timing time Tv is calculated using the control By value BvT set in #1755. Also, if Bvs>BvT,
Proceed to #1620 of "Natural Light Mode" Routine ■. In addition, in #1765, the flash emission timing time Tv is calculated from the following equation.

Ev=BvT +5v Tv=Ev-AvD =BvT +5v-AvD Next, compare the flash timing time Tv calculated in #1765 with the maximum shutter speed Tv14 or camera shake limit shutter speed TvH in #1770. #
1780), if Tv≧TvH, then the flash emission cannot be controlled, so the timing time Tv is set to the maximum shutter speed TvH (#1775), and if Tv≦TvH, the flash is emitted. To avoid camera shake, set the timing time Tv before
Set the camera shake limit shutter speed TvH (#1
785), please set the "Flash Required"flag#
1790), return to main routine (#17
95), if TvH<Tv<TvH (#17
70, #1780), using the Tv obtained in #1765, proceed to #1790-; #1795.

Next, routine (3) of the "backlight flash mode" will be explained.

First, check whether the "flash prohibition" flag is set (#1800). If the flag is set, proceed to #1625 of the "natural light mode" routine ■. If not, set the control Bv value BvT to the value obtained by subtracting the correction amount 1 and OEv from the sub-subject brightness BvA, that is, BvT = BvA - 1,0 ($1805), and set the control Bv value BvT and the main subject brightness B
Calculate the brightness difference from vS, that is, the brightness difference ΔEvN (=Bvs-BvT) from the appropriate natural light component #1810), and compare the brightness difference ΔEvN with -1°OEv (#1815), ΔEvN>- If it is 1.0, fix ΔEvN to -1,0 and control B v fMB
Set vT to the main subject brightness Bvs plus correction amount 1 and OEv, that is, BvT=Bvs+1,0, and ΔE
If vN≦-1,0, BvT set in #1805 and #1810 = Bvs + 1.0 and ΔEvN = Bvs
- Using BvT.

And Fludge, 2. Correction amount ΔE of exposure amount due to light emission
Set the coefficient K added to vFL to the value of α #182
5) Proceed to #1700 above and perform the processing from #1700 onward, which will not be explained in "dark flash mode."

By the way, in the "backlight flash mode", a predetermined timing time Tv for flash emission is calculated from the brightness of the sub-subject (however, when δ≦Bv≦2, the timing time for flash emission is calculated from the main subject brightness), and the exposure is After the start, the flash is emitted after a predetermined time Tv has elapsed, and the exposure is stopped when the main subject is properly exposed, thereby adjusting the balance of brightness between the main subject and the secondary subject in the background. In the embodiment, since the exposure is stopped when the main subject becomes suitable after emitting the flash, the main subject becomes suitable, but the sub-subject becomes overexposed by the flash emission time.

Therefore, in addition to the above-mentioned embodiment, a second embodiment that can accurately adjust the balance of brightness between the main subject and the sub-subject will be described below. Calculate X [seconds] and set the above predetermined time T
The flash is emitted X [seconds] before v elapses.

The value obtained by converting the above predetermined time Tv into [seconds] is X'',
If the timing time of flash emission is x' [seconds] after correcting the fixed time X from the same X'', then X'':= 2
T V (seconds) x′=x″−X [seconds] T v ,°, x′=2 −x [: seconds] x′ is the timing time of flash emission.

Regarding the second embodiment using the above-mentioned "predetermined time X' for flash emission in backlight flash mode J," FIG. 8(b) shows.
This will be explained using a flowchart.

The flowchart in FIG. 8(b) is inserted between #1765 and #1770 in FIG. 8(a).

First, in #1765, the flash emission timing time Tv is set.
After is calculated, check whether the reversible J flag is set (#1895), if it is not set, proceed directly to #1770; if the flag is set,
A correction amount ΔEvF from the appropriate amount of flash light is calculated from the luminance difference ΔEvN from the appropriate amount of natural light using the following equation (#1900).

ΔE v N > ΔEvF=1og2 (1-2 Next, the required flash emission amount 1v from the main subject distance
s is calculated from the following formula (#1905).

I vs=Avoz+Dv-3v Next, compare the flash light emission amount Ivs obtained in #1905 with the actual light emission amount 1v. #1910) Ivs≦Iv
If so, calculate the correction amount ΔEvF' obtained from the distance information obtained from the main subject distance and the appropriate amount of flash light amount from the following formula #1915), and calculate the correction amount ΔEvF from the table shown in Table 4. A correction time X corresponding to ' is determined (#1940).

ΔEvF' = I vs-1v+ΔEvF Also, Iv
If s>Iv, the light emission amount corrected by adding the luminance difference correction amount ΔEvF to the flash light emission amount 1vs' (
=Ivs+ΔEvF) (#1920), and the correction amount ΔBvF'' is calculated from the difference between this light emission amount Ivs'' and the actual light emission iIv (#1925). That is, ΔEvF ' = I vs' - I v Next, check whether the above correction amount ΔEvF ' is less than or equal to OEv (#1930), and if ΔEvF '> O, then Δ
EvF' should be set to O (#1935), ΔEvF'≦
If it is 0, use the unchanged ΔEvF′ and #19
Proceed to step 40 and calculate the correction amount ΔEvF from the table shown in Table 3.
′ is determined.

Next, from the X obtained in #1940 and the above predetermined time Tv, the flash emission timing time x'C seconds] is calculated using the following formula (#19451゜Tv x' = 2 -x) Next, the flash emission timing Convert time X [seconds] to Tv[:Ev] using the following formula and proceed to #1770 (#
1950).

Tv=l og2 (1/x') This completes the explanation of the second embodiment, and next, the "release" subroutine of #2000 (#1005 in FIG. 6) will be explained using FIG. 9.

The [Release] subroutine is composed of routines for "Natural Light Mode", "Flash Mode J", and "Forced Flash Mode".

First, switch SWI is switched to designate the photometry sensor as the light receiving section 17a (spot photometry at the center of the shadow screen) (#2005). This is a control that stops the exposure of the solid-state image sensor 9 when the main subject becomes appropriate. In order to do this, set the metering sensor to spot metering at the center of the shooting screen. Next, set the shooting mode to natural light mode, flash mode, or forced flash mode in #2010 and #2015. I understand. If the "forced flash" flag is set in #20i0, the process advances to the "forced flash mode" routine in #2235 to #2275 (described later), and then #201
If the "Flash Required" flag is set in step 5,
The process advances to the "flash mode" routine of #2090 to #2230 (described later), and if the "flash required" flag is not set, the process advances to the "natural light mode" routine of #2020 to #2085.

When shooting in natural light mode (#2020), first, the ISO feeling is corrected using the main subject brightness correction value ΔEvll and the imaging sensitivity variation correction value γ (#2025).

Next, timer T1 and timer 1-2 are set to -TvH, the two-divided value to of the maximum shutter speed tH (=2), and the camera shake limit shutter speed th (=2-Tv
o) and start the countdown, at the same time, start the exposure of the solid-state image sensor 9 (#203
0), then time t.

It is confirmed whether the exposure amount of the solid-state image sensor 9 reaches an appropriate level by the time the period of time has elapsed. In other words, check the timer T1-〇.
2035), if TI>O, the voltage value ■ (hereinafter referred to as exposure voltage value) of the capacitor C of the circuit 22i that detects that the amount of charge accumulation in the solid-state image sensor 9 has become appropriate and the reference voltage value ■0 Compare with #2040>, if Vo<V, the amount of charge accumulation has not reached the appropriate value, so #203
Return to step 5, check the timer Tl again, and if vO≧■, the amount of charge accumulation has reached the appropriate value, but the charge accumulation is excessive until time tH, so the gain of the captured image is - Set the flag for 1,0 correction (#2045)
, #2280 to #2290, the shutter is closed, the gain correction 1-1°0 is output to the video processing control circuit 25, and the process returns to the main routine.

If T1=0 in #2035, timer T1 is set to
to start the countdown, and then set the time to
Check whether the exposure amount of the solid-state image sensor 9 reaches the appropriate amount by the time to elapses (#2250 to #2060). If the solid-state image sensor 9 reaches the appropriate exposure amount by the time to elapses, the charge accumulation is completed at the time tH. Since this is done excessively, set a flag to correct the gain of the captured video by -0.5 (#2045), proceed to #2280 to #2290, close the shutter, and set the gain correction value -0.5. If the solid-state image sensor 9 does not reach the proper exposure by the time 0 time to elapses when outputting to the video processing control circuit 25 and returning to the main routine (TI=O in #2055), then time t H
~ t 11 4 Close the shutter (#2280)
, Since there is no gain correction, output the gain correction value O to the video processing control circuit 25 (#2285) and return to the main routine (#2290). If Vo<■, T2
=O (time tH elapsed) #2075)
, if T2=O, the exposure time of the solid-state image sensor 9 exceeds the camera shake limit time, so the charge accumulation of the solid-state image sensor 9 must be forcibly stopped (#2080), and in order to correct the underexposure, the captured image is Set the flag to correct the gain by +0.5 (+2085) and close the shutter (+2280)
, the gain correction value (), 5 is output to the video processing control circuit 25 (+2285), and the process returns to the main routine (+2290).

Next, to explain the flash mode (+2090), similarly to the natural light mode, first, the D/A conversion circuit 22h (+2095).

Next, check whether the "backlight" flag is set (+2100), and if the flag is set, +215
5-#2230 “backlight” hula-tshu mode shooting (
(described later), and if it is not set, +2105~
#2150 Normal flash mode shooting 0 In normal flash mode shooting, timer T1 and timer T2
The Tv flash light emission timing time tA (.2) and camera shake limit shutter speed to are set respectively, and at the same time as the timers T1 and T2 start counting down, the exposure of the solid-state image sensor 9 is also started (+2105). Next, T
Exposure is performed using natural light until T1=0 (time tA elapses), and when T1=0, the flash is emitted (+2110 to #2115), and at the same time, the timer '
r3) Set the time tF during which the rush is emitting light,
Start countdown (+2120), compare ('['3>Oh reference voltage value Vo and exposure voltage value ■) during flash emission, and if VO≧■, (+2125~#213
0), since the solid-state image sensor 9 has reached the appropriate exposure, +22
80 to #2290, the shutter is closed, and since there is no gain correction, a gain correction value of 0 is output to the video processing control circuit 25, and the process returns to the main routine.

Next, if Vo<V does not result in proper exposure during flash emission, the solid-state image sensor 9 will reach proper exposure before camera shake limit time tH elapses (T2=O) after flash emission (after time tF has elapsed). (+2135~#21
40), if fl normal exposure is reached, (+2140), +2
The process proceeds to +2280 to #2290 in the same way as 130, closes the shutter, outputs the gain correction value 0 to the video processing control circuit 25 since there is no gain correction, and returns to the main routine. The 0 camera shake limit time tH elapses (T2O ), if the proper exposure is not reached by the time t11 elapses, the charge accumulation in the solid-state image element 9 will be forcibly stopped.
2145), and set a flag to correct the gain of the captured image by +0.5 to correct the underexposure (+215).
0), +2280 to #2290, the shutter is closed, the gain correction value ±0.5 is output to the video processing control circuit 25, and the process returns to the main routine.

Next, the "backlight" flag is set at +2100, and when shooting in "backlight" flash mode, the "backlight" flag is set.
Please make sure the "Remote" flag is set +2155
), if the flag is not set, set the flash emission timing time ta in the timer T +21
60), when the flag is set, timer T sets the flash emission timing time t^' (=tA/2
) is set (+2195), a countdown is started, and at the same time, exposure of the solid-state image sensor 9 is also started.

If the "remote" flag is not set, when the flash emission timing time tA has elapsed (+2165
), fires the flash (+2170), simultaneously sets the timer T to the flash firing time tf, and starts countdown (+2175), and while the flash is firing (1゛〉0), the solid-state image sensor 9 takes proper exposure. If it becomes (+2180, +2190), +2280 ~ #229
0, the shutter is closed, and since there is no gain correction, a gain correction value of 0 is output to the video processing control circuit 25, and the process returns to the main routine. If proper exposure is not obtained during flash emission, the charge accumulation in the solid-state image sensor 9 must be forcibly stopped after the flash emission (after time tF has elapsed) +2
185), closes the shutter without setting the gain correction flag for the photographed image (+2280), and sets the gain correction value 0 to the image processing control circuit 25 since there is no gain correction.
(#2285) and returns to the main routine (#2290). In the "backlight flash mode" shooting in #2160 to #2185, the background is brightly backlit, so even if the exposure is forcibly stopped in #2185, no gain correction is performed on the shot image.

Even when the "remote" flag is set, the flash is emitted after the elapse of the flash emission timing time tA' in the same way as when the above-mentioned "remote" flag is not set. When the exposure is appropriate, the shutter is closed, and since there is no gain correction, a gain correction value of 0 is output to the video processing control circuit 25, and the process returns to the main routine (2200 to #2220. #2
280 to #2290), if proper exposure is not achieved during flash emission, the charge accumulation in the solid-state image sensor 9 is forcibly stopped after flash emission #2145), and the gain of the photographed image is corrected by +1.0. Set the flag (#
2230), closes the shutter (#2280), outputs a gain correction value of 1.0 to the video processing control circuit 25 (#2
285), return to main routine (#2290
).

In #2195 to #2230, when shooting in "remote" [backlight flash mode], the exposure time using natural light is half of the time t^ when shooting in [backlight flash mode], so the exposure is forced in #2225. When stopped, the gain correction of the captured video is +1°0.

Next, to explain the forced flash mode (#2235), first, the main subject brightness correction value ΔEv[[ and the ISO sensitivity Sv corrected by the imaging sensitivity variation correction value γ are output to the D/A conversion circuit 22h. (#2240). Next, the maximum shutter speed tH and camera shake limit shutter speed 1++ are set in the timers T1 and T2, respectively, and at the same time the timers TI and T2 start counting down, the exposure of the solid-state image sensor 9 is also started (#2245
). Next, when the maximum shutter speed tH has elapsed (
T1=O), flash #2250~#22
55), check whether the solid-state image sensor 9 reaches the appropriate exposure before the camera shake limit time tH elapses (T2=O) (#
2260 to #2265) 0 If the proper exposure is reached before the camera shake limit time t 11 elapses, close the shutter (#2265)
2280), since there is no gain correction, a gain correction value of 0 is output to the video processing control circuit 25 (#2285), and the process returns to the main routine (#2290>. If the proper exposure is not reached, the camera shake limit time th has elapsed. When (T
2 = O), force the charge accumulation of the solid-state image sensor 9 to stop #2270), and set a flag to correct the gain of the captured image by +0.5 to correct the underexposure #2275) , close the shutter (#2280),
Output the gain correction value +0.5 to the video processing control circuit 25 (#2285) and return to the main routine (
#2290).

This concludes the explanation of the release sequence operation.

In this embodiment, in order to downsize and reduce the cost of the device, the flash light emission stop circuit is omitted so that the flash always emits full light.

However, in order to save power, the flash may also stop emitting light when the exposure is stopped.

(Hereafter, margin) [Main]: Main subject brightness.

Bvs : Average brightness value of the shooting screen tf: Flash duration No. table

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of an optical system of an electronic camera according to an embodiment of the present invention, FIG. 2 is a system configuration diagram of the electronic camera, and FIG. 3 is a time diagram for explaining exposure time and flash emission timing. 4 is a flowchart of the main program for controlling the camera section of the electronic camera, FIG. 5 is a flowchart for executing the initial load applied to the main program, and FIG. 6 is a flowchart for executing the initial load applied to the main program. FIG. 7 is a flowchart for executing the AP applied to the flowchart of S1 above, and FIG. 8(a) is a photometric AE calculation applied to the above flowchart. FIG. 8(b) is a flowchart for explaining a second embodiment of the flash emission timing according to the present invention, and FIG. 9 is a flowchart for executing the release applied to the flowchart of S1 above. This is a flowchart for 6... Photometric sensor, 9... Solid-state imaging probe (m (j
A) 10... system controller, 22...
Control IC123...system controller, S3,3
4...Switch for setting the correction amount.

Claims (1)

[Claims] (1) A sensitivity adjustment device for an image sensor whose exposure is controlled based on photometric data from a photometric sensor is provided with a switch input terminal for setting a correction amount according to variations in the imaging sensitivity of the image sensor; Sensitivity of an image sensor, characterized in that it comprises a control means in which a correction value corresponding to an input is stored, and the photometry data from the photometry sensor is corrected based on the correction value output from the control means. Adjustment device.