JPS63124687A - Image pickup device - Google Patents

Abstract

PURPOSE:To eliminate the disturbance in a video signal due to sudden change in a shutter speed by revising the shutter speed through the transition intermediate speed from the speed before the change till the speed after the change in changing the shutter speed. CONSTITUTION:An image pickup signal from an amplifier 31 or a process 32 is given to a terminal 12001 of an aperture control circuit 12 to form a closed loop of automatic aperture control thereby controlling the image pickup signal output outputted at a terminal 3201 to a constant value. When an AE circuit 61 or a manual circuit 62 is selected by a switch SW 5001, a control circuit 5 controls a drive circuit 5 in response to the output from the circuit 61 or 62. In this case, in changing the shutter speed of a sensor 4 with shutter from T1 to T2, the drive circuit 5 changes the speed slowly in the transmission time T3 of T1<T3<T2. Thus, the disturbance of the video signal due to the sudden change of the shutter speed is avoided. When the switch SW 5001 selects the AE circuit 61, the AE circuit 61 estimates an incident light in the sensor 2. The circuit 5 controls the shutter speed of the sensor 2 trough the drive circuit 4 so as to allow the shutter speed to take values shown in figure (a) depending on the estimated value thereby suppressing the smear component.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electronic camera that performs continuous shutter photography, and particularly to shutter control suitable for a camera with a shutter function that uses a built-in shutter function sensor.

[Conventional technology]

Conventionally, a sensor in which a solid-state image sensor (hereinafter referred to as a sensor) itself has a shutter function was disclosed in Japanese Patent Application Laid-Open No. 56°-4427.
As described in Publication No. 1, there is a sensor realized by combining the reset operation of the pixel charge by an overflow drain installed in the horizontal direction, and the transfer operation to the vertical CCD after a certain period of time after reset, and Takeuchi. et al.: Picture elements by changing the potential of the vertical overflow structure as discussed in ``Driving method of vertical overflow structure CCD image sensor - Part 1j'' of Proceedings of the 1982 National Conference of Television Engineering Society 2-6 (1982) A method is known in which the reset operation is combined with the transfer operation to the vertical CCD after a certain period of time has elapsed after the reset.

In this manner, the conventional electronic camera with a shutter function changes the shutter speed by changing the charge accumulation time from photodiode reset to charge readout.

[Problem that the invention seeks to solve]

In the imaging device shown in the conventional example above, the shutter operation is performed by resetting the charge accumulated in the sensor at predetermined intervals, but if this reset operation is performed in a period other than the vertical blanking period, the reset There is a risk that the imaging signal may be disturbed by the signal. For this reason, the period in which the reset is performed is limited to the vertical blanking period, and the shutter speed can only be set to two types, approximately 1/1000 seconds and approximately 1/60 seconds.

In this way, when switching between two shutter speeds that are significantly different during shooting, the sensor exposure amount differs by more than 20 dB between 1/60 seconds and 1/1000 seconds, so the output signal sharply increases or decreases, resulting in an increase in the output signal on the screen. Disturbance occurs.

Furthermore, when an automatic exposure system used in a film camera is applied to a solid-state camera with an electronic shutter, the following problems arise. For film cameras, Program A
E (Auto Exposure) etc., and the fifth
As shown in figure (a), as the subject becomes brighter,
Control is performed to increase the shutter speed and to narrow down the image. With a film camera, once the focus has been narrowed down to a certain extent, the higher the shutter speed, the better the picture you can take, so if the subject is very bright, the shutter speed is set to the maximum speed the camera has. When the program AE system described above was applied to a solid-state camera with an electronic shutter and image quality was evaluated, the following problems were discovered.

If the subject is a special image (for example, a gleaming object or an object that emits strong light), increase the shutter speed as the subject becomes brighter (and a noise called smear is likely to appear. Find out the cause. If you look at it, you will see Figure 5(b).
As shown in Figure 2, it was found that when the amount of light incident on the sensor is kept constant and the shutter speed is increased, the amount of smear noise remains the same, only the video signal is attenuated, and the S/N ratio of the video output signal is deteriorated. Although electronic shutters can in principle have extremely high shutter speeds of 1/10,000 seconds or less, it has been found that even if the shutter speeds are made extremely high, they only worsen the smear noise characteristics. If the shutter speed is set too high for a moving image, the image may look like a strobe shot depending on the content of the subject, making it difficult to view.In the end, it is necessary to set a preferable shutter speed for moving images, unlike for still images.

Therefore, from the above, it can be seen that it is not preferable in terms of use to increase the shutter speed without limit unless it is manually set.

A first object of the present invention is to eliminate screen disturbances during shutter speed switching as explained in Problems 1 and 2 above. Second
The purpose of this is to suppress the appearance of visitors due to smear and to eliminate the difficulty of viewing due to strobe images.

[Means for solving problems]

In order to prevent the signal level of the video signal from suddenly changing when the shutter speed setting value is changed, the imaging device of the present invention has the advantage of changing the shutter speed from the pre-change shutter speed to the post-change shutter speed when changing the shutter speed. A shutter speed changing means is provided for changing the shutter speed from a pre-change shutter speed to a post-change shutter speed through an intermediate shutter speed between the two.

[Operation] When changing the shutter speed from shutter speed T1 to T2, the shutter speed changing means satisfies the condition that TI≦T3≦
After passing through T2 and T3, the speed is gradually changed.

This eliminates disturbances in the video signal due to sudden changes in shutter speed.

〔Example〕

Before explaining specific embodiments of the present invention, using FIG. 1,
The present invention will be described in detail.

In FIG. 1, 11 is an aperture, 12 is an aperture control circuit including the driving part of the aperture 11, 2 is a sensor with a shutter, which is a sensor with a built-in shutter function, 31 is an amplifier that amplifies the imaging signal from the sensor, and 32 is an aperture control circuit including the driving part of the aperture 11. This is a process in which the signal from the amplifier 31 is subjected to signal processing such as gamma processing to become a video signal, and the video signal is output to the terminal of the amplifier 3201.

4 is a drive circuit for the sensor with shutter 2, 5 is a control circuit for controlling the drive, 5001 is a SW, 61 is an AE circuit for performing automatic exposure control (hereinafter abbreviated as AE), 62 is a shutter speed, etc. This is a manual circuit for selecting the shutter speed manually.

An example of a senna with a shutter is shown in FIG. 2(a).

The figure shows the case of MO3 type cell.

2111 is a horizontal scanning circuit, 2112 is a reading scanning circuit, 2113 is a reset scanning circuit, 2116 is a picture element, 2
114 is a vertical gate line, 2115 is a horizontal gate line, OX
I, OX2゜... is the number attached to the vertical gate line,
OYI, OY2... are numbers attached to the horizontal gate lines to distinguish the signal output from the readout scanning circuit 2112 from that of the reset scanning circuit 2113, 0RYI, 0.
The same applies to RY2.

In operation, first, the reset scanning circuit 2113 and the horizontal scanning circuit 2111 scan the group of picture elements 2115 to reset the charges. Next, readout scanning circuit 2112 and horizontal scanning circuit 2
111 performs a readout scan, and outputs the signal charge accumulated in the picture element 2115 during the reset scan and readout scan to the outside of the sensor as an imaging signal.

At this time, if the reset scan and readout scan are performed within one vertical scanning period, the accumulation time of the signal charge on the picture element is, for example, 1.
If the vertical scanning period is 1/60 second, it will be shorter than this,
Moreover, an accumulation time, that is, a shutter speed nine times as long as one horizontal scanning period can be obtained. Here, since the picture elements in the same column of each row selected in the reset scan and read scan are scanned at the same time, it is of course necessary to lead them out through separate signal systems.

In the above configuration, the aperture control circuit 12 includes an amplifier 31
Alternatively, the imaging signal from the process 32 is applied to the terminal 12001 to form a closed loop for automatic aperture control, and the imaging signal output to the terminal 3201 is controlled to be kept constant.

Note that an MOS type sensor is shown as an example of the sensor. This is because, as mentioned above, in the case of a CCD type sensor, for example, in the case of an interline type CCD, it is difficult to continuously vary the shutter speed. However, for example, Sugimoto et al.: Television Society Technical Report, published July 24, 1986, PP0E68-3. PP9-14 l'-NAB new product introduction = COD camera with shutter, DVE = As mentioned in J, it is possible in the case of interline frame transfer type COD, which is a combination of interline type and frame transformer type 77 in 5. . This is because the vertical CCD section and the storage section are independent, so noise from shutter operation is less likely to be mixed in during reading of the image signal.

Therefore, it goes without saying that a CCD type sensor of the same type or an interline type sensor that can reduce noise due to discharge of charges at the time of reset may be used. The present invention will be explained based on the above-mentioned MO3 type senna.

An example of switching between 7 Al and AE is shown in Figure 2 (bl
Shown below. In the same figure, 50012 is the switch body, 50
011 is a switch selection section, 50013 is a switch (or volume) for switching speed in manual mode, 50014
A is the automatic exposure control position, 1M is the manual control position, and 50016 is the shutter speed. For example, in the NTSC system, Tvl is 1/60, etc.

In this configuration, when the selection section 50011 is turned on the A 50014 side, automatic exposure control is performed, and when the selection section 50011 is turned on the M 50015 side, the switch (or volume) 500
The shutter speed changes continuously to the shutter speed indicated by 13.

Selection section 500 from M 50015 side to A 50014 side
Needless to say, when 14 is switched, control is automatically transferred immediately. Further, the control may change in a seesaw or rotary manner such as automatic → Tvl → Tv2 →..., but the details will be omitted.

First, the problem of image disturbance due to sudden changes in shutter speed will be explained in more detail with reference to FIG. 3, and how the technical means illustrated in FIG. 1 will work to solve this problem will be described.

Figure 3 (al) shows the shutter speed, aperture, and imaging signal of a conventional camera with a shutter.
(a) is the shutter speed, (b) is the aperture value, (c) is the imaging signal, and the horizontal axis represents time. The aperture is a closed-loop control aperture commonly used in video cameras. In the conventional example, the shutter speed varies widely and discretely as shown in (a). Now, if we consider the case where the shutter speed becomes faster, the diaphragm also operates in the direction of increasing the amount of imaging signal and opens as shown in (b). However, since the change in shutter speed is large and fast, the response of the aperture control loop cannot follow it, and as shown in the image signal (c), the -image-carrying signal decreases, and then the aperture control loop automatically adjusts the aperture so that the aperture value becomes appropriate. Returns to normal level as control responds. Therefore, the screen is distorted every time the shutter speed is changed. This is shown in Figure 3 (
This can be prevented by gradually changing the shutter speed as shown in (to the shutter speed of bl). Since the response of the diaphragm control system can sufficiently follow small changes in the imaging signal caused by changes in shutter speed, the brightness of the screen does not change significantly and is hardly perceptible to the user.

From this point of view, the shutter speed may be varied according to discrete values in small steps, as shown in FIG.

In this case, it goes without saying that the value should be such that almost no screen change is detected.

In the block diagram shown in FIG. 1, for example, when the SW5001 selects the manual circuit 62 and the input setting value of the manual circuit changes, the control circuit 5 controls the drive circuit 4 and the shutter This is realized by gradually changing the shutter speed of the attached sensor 2. In this case, the aperture 11 is, for example, the process 3201
It is assumed that the auto iris operation is performed by the aperture control circuit 12 inputting the luminance signal from the iris to the terminal 12001. Therefore, the diaphragm 11 also changes in accordance with the change in the shutter speed of the sensor with shutter 2, and the imaging point output remains constant as shown in (f) of FIG. 3(b).

Next, the second problem is explained in more detail in Figure 5 (cl, (
ci), and how the technical means illustrated in FIG. 1 work to solve this problem.

Second Problem: As shown in FIG. 2(c), noise due to electric charge that wraps around the vertical CCD and the signal line, so-called smear noise, increases in proportion to the incident light on the sensor. Increasing the shutter speed means that only a part of the incident light is used as an imaging signal, which lowers the sensitivity and therefore increases the amount of incident light (as shown in bl, the shutter speed and smear noise are in a proportional relationship. Therefore, unless the speed is manually set by the user, the shutter speed is not increased indefinitely as shown in FIG. 4(d), but smear noise is suppressed by setting a limit.

In the block diagram of FIG. 1, this means that the AE circuit 61 is
If W5001 is selected, the AE circuit 61 estimates the light incident on the sensor from the aperture value detection circuit of the aperture 1 (not shown), an external photometry circuit, etc. The control circuit 5 controls the shutter speed of the shutter-equipped sensor 2 through the drive circuit 4 to suppress the smear component so that the shutter speed takes a value as shown in FIG. 5 (cl) according to this estimated value. Similarly, the suppression of stroboscopic imaging effects (afterimage effects caused by the eyes) is also reduced because the shutter speed is suppressed.

As described above, the problems that have conventionally occurred are solved by the operation of the value capturing apparatus shown in the block diagram of FIG.

It goes without saying that the present invention can provide many embodiments depending on the implementation method and connection method of each block.

It has been mentioned that the diaphragm control system cannot respond to sudden changes in the shutter speed, but this is because the diaphragm is usually composed of mechanical parts, and it is difficult to increase the response speed due to the inertia of the diaphragm. However, if you use a liquid crystal, etc. and an aperture with a sufficiently fast response speed, such as an electronic aperture device, it is possible to suppress screen disturbances by instantly changing the aperture value according to the shutter speed. Needless to say. In the present invention, assuming a mechanical diaphragm that has been commonly used in the past, diaphragm control is performed using closed-loop control that performs control according to a signal proportional to the amount of incident light such as an imaging signal, and the response speed of the control is We will discuss the case with a time constant.

Hereinafter, a specific embodiment of the present invention will be described with reference to FIG. 1 again. The operations of the blocks are as described above.

Assume that the manual circuit 60 is selected as SWl, and the shutter speed of the shutter-equipped sensor 2 (hereinafter referred to as Tv using the apex display) is input so as to change from Tvl to Tv2. At this time, the shutter speed change is the sixth
As shown in Figure (a), if the control circuit 5 changes Tvl to Tv2 from time t1 to t2, the response of the diaphragm 11 causes almost no disturbance of the screen to be perceived, resulting in a good manual setting operation. Since the operation specifications of the control circuit 5 and the manual circuit 60 are determined, they can easily be configured using a microcomputer, variable resistors, and switch input devices, but they are also part of a shutter speed setting circuit that is composed of individual components. An example is shown in FIG. 6(b) and will be described below.

(In figure b1, 61101 is a manual input device and is represented as a changeover switch in this example. 61102 is a decoder that converts the input from the input device 61101 into digital information for the necessary bits, 61103 is an AND of the inverted input row, and 61104 is an AND of the inverted input row. Up/down (U/D) counter that can count up (0.down ■), 611
05, 61107 is a digital comparator, 6110
6 is a counter, 611031 is a terminal to which a vertical synchronization pulse is input, 611061 is a terminal to which a horizontal synchronization signal is input, and 611071 is a terminal to output a reset readout start timing signal VIN'. Note that the shutter speed of the sensor with shutter 2 is determined by the reset scanning circuit 21 in Fig. 2.
The shutter speed at this time is determined by the time difference between the scan start timing signal VIN of No. 13 and the scan start timing signal IN of the readout scanning circuit 2112.
(f) Tv as shown in the explanatory diagram of shutter speed settings in Figure (c).

In the following explanation of shutter speed control, since the readout scan has almost the same timing as the vertical synchronization pulse, the explanation will focus only on the reset scan start timing signal VIH.

The operation in FIG. 6(b) first involves the decoder 61102 and the U/
Comparator 6 compares the output with D counter 61104.
Do 1105 ka. If the two outputs are equal, the comparator 61105 outputs H (the logical value is 1) to the terminal 611052, and if they are not equal, it outputs L (the logical value is 0), and if the output of the comparator 61105 is large, it outputs the terminal 611052. 61
If H2 is small at 1051, L is output. Moreover, if the output of the terminal 611051 is H, the U/D counter counts up by the trigger from the terminal 611032,
If it is L, count down. Therefore, the input device 611
If the output of the decoder 61102 due to 01 is smaller than the U/D counter 61104, the U/D counter 61104 is counted up through the A N D 61103 for each pulse inputted to the terminal 611031.

This count output and the H input from the terminal 611061
When the count output of the pulse counter 61106 reaches one value, a pulse is generated from the comparator 61107 to the terminal 611071, which becomes the reset scanning pulse vrN. Although not shown, the counter 61106 is of course reset for each V pulse. The timing at which this reset scanning pulse V/N' is generated is within the vertical scanning period, and until the output from the decoder 61102 reaches one value,
It is clear from the above circuit configuration and explanation that each pulse is delayed by the H pulse width. That is, the shutter speed changes in a stepwise manner as shown in (g) in the shutter speed change in FIG. 6(a).

It is clear that when the input device R61101 changes, the shutter speed corresponding to the input value will also change for each pulse, so we will omit the details.

It has been found through experiments that even if the IH is changed for each pulse input, the response speed of the aperture control is usually sufficient and no deterioration in image quality is observed. This is particularly noticeable when the shutter speed is slow, and in such a case, it goes without saying that the shutter speed may be changed by several H pulses every pulse.

This allowable shutter speed change value is shown in FIG.

This shows that the lower the shutter speed is, the larger the change width (shutter speed change value) can be.

If the shutter speed is changed according to this curve, usability will be further improved. However, this curve itself is determined by the response of the aperture control circuit system and the permissible value of screen brightness change.

The method for realizing this is, for example, in FIG. 1, if the drive circuit 4 of the sensor with shutter 2 is controlled by the control circuit 5 composed of a sufficiently high-speed microcomputer, first the V pulse and the H pulse are taken in, and the V pulse is The shutter speed is controlled by the count number of H pulses from and the set value of the VIN pulse. At this time, the current VIN'
This can be easily achieved by comparing the set value of the pulse with the corresponding value of the manual circuit 61 in the data shown in FIG. 7 inputted in advance and changing the set value of the MIN pulse according to the width of change.

Next, an embodiment in which the SW 5001 selects the AE circuit 61 in FIG. 1 and performs the AE operation is shown in FIG. 8 and will be described below. In the figure, the SW shown in Figure 1
l, etc. have been omitted. Blocks with the same numbers as in FIG. 1 are blocks that perform the same operations. 622 is sensor 2 with shutter
The control circuit 5 controls the shutter speed based on this output.

In the AE operation described below, the shutter speed is kept below a certain value as shown in (wa) of FIG. 9 in order to suppress the smear component mentioned in the conventional problem section. Note that this value itself may not be changed to the characteristic curve shown in ψ) in the same figure in accordance with the concept of the AE program or the improvement of the smear component, but the essence of the present invention is to set a limit on the shutter speed. Therefore, the following explanation will be given assuming that the characteristic curve shown in (W) is taken.

Now, first, the incident light to the sensor, that is, the output of the well portion having a brightness detection function will be explained using FIG. 10. The figure shows a cross-sectional view of the vicinity of the photodiode of an MO8-type sensor. For example, the NPN structure type MO8 imaging for a single-chip color camera by Kobu et al. This is discussed in a paper titled ``Characteristics of Elements''. In the same figure, 11021 is Si02, 11022 is an n-type diffusion layer, 11023 is a P-type well, and the n-type diffusion layer 1102 is
2 constitutes a photodiode. 11024
is the n-type sub, 11025 is the gate of the MOS switch, 1
1027 is an n-type diffusion layer forming the drain of the MOS switch, 11026 is an electrode forming an output signal line, 11
028 is preamplifier, 11029 is ammeter, 11021
1 is a power supply. Pairs of electrons and holes are generated in the photodiode section (Y) by the incident light. The electrons are output as imaging signal charges to a terminal 110281 through a preamplifier 11028- in response to a readout pulse from a gate 11025 or the like. Holes, which are one of the charges generated in the pair, flow through the P-type well 11023tA, through the ammeter 11029, and into the power supply 110211.

The current flowing through the output terminal 110291 of the well 11023 is called a well current. Since this well current is due to holes generated by the incident light, it has been experimentally confirmed that it is proportional to the amount of incident light, and that the response speed is sufficiently fast (approximately equivalent to that of a PiN photodiode). An example is shown in FIG. The MO8 type sensor used was Hitachi HE.
98335, and it was confirmed that there is linearity from several lx to more than lx.

We have described the case of the MO8 type sensor regarding Hall current detection above, but of course the CCD type sensor also detects the pair-generated Hall current and knows the amount of incident light to the sensor. It was confirmed that it has characteristics against output. However, this was confirmed using the output from the sub section instead of the well section of the photodiode.

The feature of this well output is that even if the amount of imaging signal changes with respect to the amount of incident light by changing the shutter speed, it is proportional to the absolute amount of incident light itself, so you can always know the amount of light incident on the sensor. This is possible.

The operation of the embodiment shown in FIG. 8 will be explained with reference to FIG. 12.

In the figure, the horizontal axis shows the brightness of the subject, and the vertical axis shows the aperture value and well output. Also, in the curves in the figure, (T) and (E) are narrowed down, and (U) and (U) indicate the well output characteristics.

Characteristics when no AE operation is performed are shown by (T) and (T). This is because the brightness and well output increase proportionally until the subject becomes bright (the point at which the aperture control circuit 12 tries to close the aperture 11 (L/l). After that, the aperture control circuit 12 operates and controls the aperture 11. Therefore, there is only a certain amount of incident light on the shutter-equipped sensor 2, and the well output remains at a constant value.For example, in the NTSC system, the shutter speed remains at the minimum speed of 1/60 to obtain initial sensitivity. In the example, the operations shown in (E) and (C) are performed by the well output detection circuit 622 and the control circuit 51C.In other words, when the sensor output reaches the specified level at the position (I), it is detected by the aperture control voltage, etc. The control circuit 5 shifts the shutter speed to a higher side when the incident light further increases.This shift is performed until the well output reaches a certain set value.Up to this point, the characteristic curve of the aperture is as follows. When the well output reaches a certain value, the shutter speed is fixed and the incident light is controlled by the diaphragm.Therefore, the characteristic curve factor is (C) changes. In this way, the imaging output is controlled by varying the shutter speed until a certain brightness level, and then the shutter speed is kept constant to suppress the occurrence of smear. The program diagram in this case is shown in (1) of Figure 13. Show.Tv
In the case of the NTSC system, l indicates 1/60 seconds, and Fvl indicates the aperture value of the lens used. (The slope represents normal video camera operation in which the shutter speed is not changed. Note that EV represents the exposure amount, and the higher it goes, the brighter it is.

Since the well output is a Hall current, it is passed through a current-voltage conversion circuit, converted to voltage, A/D converted, and input into a microcomputer.The AE circuit operates on the program line as shown in Figure 13. That is, first, the shutter speed is fixed at 1/60 seconds, the auto iris operation is performed by the aperture control system, and then the well output is set at a predetermined constant temperature (Figure 12).
This can be achieved by increasing the shutter speed until the

By the way, if the brightness of the subject is insufficient, the aperture control circuit 12 attempts to further open the aperture 11 in the auto iris operation.・For example, the diaphragm 11 uses the restoring force of a spring to close the diaphragm, and the driving current of the drive coil to open the diaphragm.When the operation stops, the diaphragm closes and protects the sensor. In this case, there is a characteristic between the current of the drive coil and the aperture value as shown in FIG.

This is because the closed-loop gain of the control system is high during auto-iris operation, and even if there is a slight lack of light, a large current will flow through the drive coil in an attempt to open the aperture further. Therefore, by using this characteristic, an insufficient amount of light during auto-iris operation can be immediately detected. This can be easily realized, for example, by detecting the drive current at the point ( ) in the figure using a comparator. Although we used current detection, of course the coil has a resistance component, so a voltage drop occurs, and the voltage change has the same characteristics as shown in Figure 17, so it is easy to detect the opening of the aperture based on the voltage. can.

An embodiment of this detection circuit is shown in FIG. 11, 1
2 has the same function as the block with the same number in FIG. 1, and 12
201 is a voltage source, 12202 is a comparator, 1
2203 is a terminal from which an open detection output is generated.

Therefore, when this open detection output becomes H, the control circuit 5 stops the increase in the shutter speed because the amount of light is insufficient before the shutter speed reaches Tv2 in FIG. Furthermore, if the open detection output continues to occur, the shutter speed is reduced.

By performing the above-described control, the control can be placed on the program line indicated by (X) in FIG. 13 without malfunctions resulting in insufficient light quantity due to changes in shutter speed.

In the above explanation, the shutter speed is first identified at 1760 seconds and the auto iris operation is performed, but it goes without saying that the shutter speed may be increased immediately until the well output increases to a predetermined value.

The control operation of the control circuit 5 has been described above. Next, an embodiment in which these detection and control circuits are constructed from individual components is shown in FIG. 14 and will be described below.

In the same figure, 2001 is a terminal into which the well output from the sensor with shutter 2 is input, 62202 is an amplifier, 62
201 is a resistor R, which performs current-voltage conversion with an amplifier 62202 and outputs the result to a terminal 62211.

62204 is a comparator, 62203 is a threshold circuit, and the output of the aperture open detection output terminal 12203 determines the detection threshold of the well output in cases other than open aperture. Therefore, when the diaphragm 11 is in a state other than open, the output of the comparator 62204 is generated at the terminal 62212 by detecting a well output equal to or higher than the value (c)' in FIG. 12, for example. However, when the aperture 11 is open, the comparator 62
The output of 204 is not generated. 62205 is a low pass filter (LPF) that determines the time constant of the shutter speed control system and stabilizes the operation. 62213 is a terminal, and the shutter speed is varied by this terminal output vT. 52
A shutter speed setting circuit outputs a reset scanning start timing signal vIN from a terminal 52002 in accordance with the human power vT. Terminal 52001 is an input terminal for vertical synchronization signal V, and VIN is generated based on this. It can be seen that with the above configuration, the shutter speed is determined according to the well output and the aperture opening detection output used for detecting insufficient light quantity, and control according to the program line (2) in FIG. 13 can be obtained. In other words, except when the aperture is wide open, the TU value becomes T.
It operates to move to U2, and when the aperture is opened, T
Perform an action to stop or reduce the increase in the U value.

An embodiment of the shutter speed setting circuit 52 is shown in FIG. 15 and will be described below.

52013 is a switch SW, 52014 is an amplifier, 5
2010 is a voltage source, 52011 is a resistor, and 52012 is a capacitor, and by pulse input to the terminal 52001, the resistor 52011, capacitor 52012, and voltage source 520 are connected.
10 and an amplifier 52014 form an integrating circuit, which is reset in accordance with the (1) pulse and generates a triangular wave. This is shown at 52004 in FIG. By inputting the shutter speed control voltage vT with a comparator 52015, the triangular wave pulse inputted to the terminal 52004 is compared and becomes the pulse shown in FIG. 6 52005, and the rising edge of this pulse becomes the reset scanning start timing.

Note that the reset scan start timing pulse VIN is normally synchronized with the horizontal synchronization pulse, so the horizontal synchronization pulse H is input to the terminal 52006, and the NAND of 52018,
52016 inverter, 52017, 52019
The D-type free-lag flop performs so-called re-beating and outputs the signal. Waveforms of each part of this circuit are shown at 62213 to 52008 in FIG.

The operation of this circuit will be briefly explained below. A pulse 52005 whose pulse duty changes according to the shutter speed control voltage VT 62213 and synchronized with the fall of the v pulse 52001 is output to the terminal 52005. is temporally enlarged and is represented again as a waveform 52005 with the same number attached to the fifth position in FIG.

Also, an H pulse 52006 is shown at the same time. pulse 5200
5 is input to the D-type flip-flop 52017, it is latched at the rising edge of the H pulse 52006, and its output appears at the rising edge of the VIN pulse 52002 waveform to the terminal 52002. When this H pulse is input to the D type flip-flop 52019, this clock φ2 is converted to the H pulse 52006 by the inverter 52016.
Since it is an inverted signal of H pulse 52006, it is latched at the falling edge of H pulse 52006. Therefore, the waveform 52 is on the terminal 52007.
It appears as a standing hi-hi as shown in 007. This H pulse 52007 and H pulse 52006 are NAND
52018, its output becomes waveform 52008, and is input to the reset terminal R1 of the D-type clip-flop 52017. If this reset terminal R1 is a terminal to be reset at L, this waveform 52008 will cause D
The type clip flop 52017 is reset and the waveform 52002 becomes the falling edge of VIN. Similarly, since the input of the D type flip-flop 52019 becomes L, it becomes L at the falling edge of the H pulse 52006. Therefore, terminal 5200
2, it can be seen that a V-force N' pulse that is H only during one horizontal period after the rise of the shutter speed control pulse 52005 can be generated.

Therefore, in this embodiment, the shutter speed can be varied according to the vT value.

Below, A for video cameras with shutters using external metering method.
An example of E will be described.

In FIG. 19, 11 is an aperture, 12 is an aperture control circuit, and 2
is a sensor with a shutter, 31 is an amplifier, 32 is a process,
7 is a photometric circuit, 5 is a control circuit, 4 is a drive circuit,
And 321 represents a video output terminal.

In this embodiment, the shutter is controlled to a shutter speed according to the brightness of the subject based on the result of external photometry, and the aperture is controlled by auto-iris that feeds back the video output as in a normal video camera. The photometric output obtained by the photometric circuit 7, that is, the brightness information of the subject, is input to the control circuit 5. In the control circuit 5, the brightness of the subject is at a level 5 (the photometric output is Ml) as shown in Fig. 20.
In this invention, we use the NTSC system as an example, so the shutter speed should always be 1/60 second (hereinafter referred to as S) GC, and the brightness of the subject should be at a certain level (
As mentioned earlier, when the photometric output exceeds Mll), the shutter speed is set to a predetermined shutter speed (1/kS) to prevent smearing, and at other times, the shutter speed is set according to the brightness. The signal is transmitted to the drive circuit 4. In this way, the drive circuit 4 drives the sensor with shutter 2 according to the shutter speed determined by the result of external photometry. Therefore, unless the brightness of the subject changes, sensor 2 with shutter
is driven at a constant shutter speed. Sensor with shutter 2
The output is amplified by an amplifier 31, subjected to signal processing such as gamma and correction in a process 32, and then transmitted to the video output terminal and simultaneously input to the aperture control circuit 12. The aperture control circuit 12 controls the aperture amount of the aperture 11 and adjusts the amount of light incident on the shutter-equipped sensor 2 . That is, the aperture control is always performed using auto-iris control that feeds back the video output.

If the brightness of the subject changes during shooting, the shutter speed is reset to a value based on the photometry results after the change. At this time,
As mentioned above, the shutter speed is changed continuously so that the video output does not change suddenly.

Control of the shutter speed and aperture in this embodiment when the brightness of the subject changes will be explained with reference to FIG.

When the brightness of the subject is less than Ll (photometric output MJ) (a), the shutter speed is fixed at 1/608, so only the aperture is controlled in response to changes in brightness. Furthermore, since the shutter speed is fixed at 1/kS (when the brightness of the subject is equal to or higher than Lh (photometric output Mh)), only the aperture is controlled in the same way.

The brightness of the subject varies from LJ to Ijn (LJ (+<Lh)
(b), the shutter speed also changes. At this time, if you control the shutter speed in synchronization with the brightness change (al), the aperture performs auto iris control to compensate for the error in external metering, and
/608 fixed), the change in aperture is smaller due to the change in shutter speed, which has the effect of reducing video output fluctuations due to response delay of auto-iris control. However, if the brightness of the subject changes momentarily, the shutter speed may vary and the screen may become distorted. Also,
If the shutter speed control has a time constant, for example, it also serves as the response speed of the auto iris control (b), fluctuations in the video output will be reduced by the change in shutter speed, but the time it takes to settle down to the appropriate level will be longer than before. Same as , it depends on the aperture. Rapid changes in brightness are controlled with a time constant, so the shutter speed does not change suddenly.

Therefore, if a time constant is provided for shutter speed control in consideration of the responsiveness of auto-iris control, better AE characteristics can be obtained than in conventional video cameras.

FIG. 22 shows an example of the configuration of the photometric circuit 7 and the control circuit 5. The photometric circuit 7 includes a photometric element 742 such as a 5PD (silicon photodiode) and a logarithmic compression diode 74.
1. It is composed of a log amplifier consisting of an operational amplifier 743. The control circuit 5 includes a clip circuit using a diode, an LPF 541 for providing a shutter speed control button time constant, a shutter speed setting circuit 542, and an output terminal 543. The output terminal is connected to the drive circuit 4 described above. The photometric circuit output (2) and the clip circuit output (2) out shown in the figure each have characteristics as shown in FIG. 23.

Further, the photometry circuit 7 is constructed by reusing a conventional auto white balance circuit as shown in FIG. 24, and can be realized at low cost.

A configuration diagram of another embodiment of the present invention is shown in FIG.

33 is a VTR. Others have the same functions as those shown in FIG. 8 with the same numbers. In this embodiment, in order to set an appropriate shutter speed, the diaphragm is fully opened and the illuminance of the subject is measured from the well current obtained at that time. Of course, while the aperture is fully open, the auto iris control is turned off, resulting in overexposure and distorted images. However, in general, when recording on a VTR, it takes about 1 second from when the recording switch is pressed to when the recording actually begins. This is the time required for the tape to contact the head. If photometry and shutter speed setting are completed within this time, the above-mentioned screen disturbance will not be recorded.

The details of the operation of this embodiment will be explained below. A timing diagram of the operation of this embodiment is shown in FIG. From the top row, record (
(hereinafter abbreviated as REC) Standby, REC start pulse output when the recording start switch (not shown) of the VTR 33 is pressed, actual recording start timing, aperture, well output, sampling pulse for sampling well output, sampling and holding Represents well output.

At time t, the KREC enters standby state and loads the tape. When the REC start switch of the VTR 33 is pressed at t2 and a REC start pulse is input to the control circuit 5, the control circuit 5 controls the aperture control circuit 12 to fully open the aperture for the period from t2 to t4. Hold the sample at a place where the well output voltage is stable. In reality, the well output, including the time required for the aperture to open, is stabilized at several tens of m5ec. The held well voltage is input to the shutter speed setting circuit described above, and the shutter speed is set according to the illuminance of the subject.

Note that at the end of the sample hold (t4), the diaphragm returns to auto-iris operation, and the diaphragm is controlled so that the amount of exposure is appropriate for the set shutter speed.

After setting the shutter speed, recording actually starts at t5.

FIG. 27 shows an example of a circuit that realizes this embodiment.

551 and 552 are monostable multivibrator-155
3 is an OP amplifier, 554 is a diode, 555 is a DC power supply, and OF amplifier 553 and diode 554 constitute a logarithmic amplifier that converts the well current into voltage.

556 is a MOS switch, 557 is a capacitor, 558
is an OP amplifier and constitutes a sample and hold circuit. 559 is an aperture control circuit which compares the aperture control voltage with a reference voltage using a comparator 560 and applies the output to an aperture drive coil 562 through an amplifier 561 to drive an aperture 563. 564 is a feedback coil. Normally, auto-iris operation is performed in response to changes in the aperture control voltage. When the REC start pulse is input at t2, the Q outputs of the monostable multivibrators 551 and 552 become high from t2 to t3 and from t3 to t4, respectively. When the sum of both is taken by the OR circuit 566 and the transistor 5650 is added, the transistor 565 is added between t2 and t4.
turns on. Therefore, a large current flows through the aperture drive coil 562 and the aperture is fully opened. Monostable multivibrator-5
Between t3 and t4 from 52, the H pulse is applied to MOS switch 5.
56, the well output when the aperture is fully open is sampled, and is held in a capacitor 557. The hold voltage is output to a shutter speed setting circuit, and the shutter speed is set. After sampling is completed, transistor 565
is turned off, so the aperture drive circuit 12 returns to auto-iris operation.

According to this embodiment, with a simple circuit configuration, it is possible to obtain a good image by eliminating the influence of image disturbance caused by changing the shutter speed in a recorded image of a VTR.

FIG. 28 shows another embodiment. In this example, the shutter speed Tv
The aperture value detection signal is used for control. 616
0 is an aperture detection circuit, and the others are the same as in FIG.

This control characteristic is shown in FIG. Initially, the aperture detection circuit 6
160 and the control circuit 5 control the shutter speed Tvl (
An image pickup signal is obtained from the shutter-equipped sensor 2 which is driven at a speed of 1/60 seconds (in this case, 1/60 seconds), and an auto iris operation is performed (region (3)). The subject becomes brighter and the aperture value is F.
When it is detected that v1 has been reached, the shutter speed is increased (- region). Shutter speed Tv and aperture value Fv during shooting
Where is it on the characteristic curve shown in Figure 30?
The control circuit 5 can detect the shutter speed using the aperture detection circuit 6160 and the set value of the shutter speed, so if the shutter speed is near the curve of the tide, the shutter speed is maintained as it is. If the control circuit 5 detects that the aperture is narrower than the aperture determined in FIG. 30 for the current shutter speed, the shutter speed is further increased. However, if it is detected that the shutter speed has reached Tv2 and the aperture value is Fv2 or higher, the shutter speed is fixed at Tv2 and the auto iris operation is performed ((to) region). With the above control sequence, an AE operation that almost follows the characteristic diagram shown in FIG. 30 can be obtained.

This control sequence can be easily realized by using a micro combinator in the control circuit 5 and converting the aperture value detection voltage into VD and taking it in.

FIG. 29 shows an embodiment in which this control circuit is constructed from individual components, and will be described below.

In the figure, 111 is a subject, 110 is a lens, 11 is an aperture, 2 is a sensor with a shutter, and 6161 is a potentiometer that is configured to be driven in conjunction with the aperture blades to detect the constant weight of the aperture, as an example of detecting the aperture value. , 616
2 is an amplifier for converting to an appropriate level, and 6163 is a low pass filter (LPF). 6164 is resistance, 6165
, 6167 are diodes, 6166 and 6168 are voltage sources v1. v2, and constitutes a shutter speed limiting circuit 6169 that limits the upper and lower limits of the output of the LPF 6163 and determines the range of change of the output (■T) of the terminal 62213. The output vT is a shutter speed control voltage and is led to a shutter speed setting circuit (not shown). One embodiment of the shutter speed setting circuit itself has already been shown in FIG.

With the above configuration, when the aperture value exceeds a certain value, it falls within the limits of the shutter speed limiting circuit 6169, so the output v changes, and the shutter speed is changed by the shutter speed setting circuit that inputs this. If the time constant of the LPF6163 is set longer than the time constant of the auto iris system, it will be stabilized within a certain range of subject brightness, that is, the aperture value and the shutter speed in the 30th thread range. Further, as the subject becomes brighter, even if the output of the amplifier 6163, which is the detection output of the aperture value, changes further, the shutter speed does not change due to the limitation of the shutter speed limiting circuit 6169, resulting in the characteristic in the region (a) of FIG. 30.

As described above, according to this embodiment, the shutter speed vs. aperture characteristic shown in FIG. 30 can be realized, and smear can be suppressed.

Up to now, in the case of AE operation, we have explained that the shutter speed is always changed continuously depending on the photometric value, aperture value, etc., but several shutter speeds are determined and one of them is changed depending on the photometric value, etc. It goes without saying that the auto iris operation may be performed while the shutter speed is fixed at the selected shutter speed. At this time, if the photometric value etc. deviates from the standard for selecting the shutter speed, select another shutter speed and continuously change the shutter speed toward that shutter speed as described in the manual circuit above. Bye. It is clear that the shutter speed vs. aperture characteristic at this time can be stabilized by providing hysteresis characteristics.
An example of this is shown in FIG. 31(a).

Shown in (b). In the figure, the solid line portion is a region where the shutter speed is fixed and exposure control is performed by auto-iris control, and the arrow indicates where control is performed by opening the aperture. The broken line indicates that when the control unit detects that the aperture value has reached a certain limit at each shutter speed, the shutter speed is changed in the direction indicated by the arrow toward the next shutter speed.

Figure 31(a) shows the five shutter speed setting points (
b) shows an embodiment with two shutter speed set points. It can be seen that the AE operation is performed while a small hysteresis characteristic is drawn in the same figure (al), but a large hysteresis characteristic is not drawn in the same figure (bl).

The above-mentioned control circuit can be easily realized by a person skilled in the art using a microcomputer or the like as described above, since the detected value is known and the operation sequence is clear. Therefore, here, an example of an implementation circuit that realizes the embodiment of the same figure (bl) using individual components is briefly shown in figure v132.

61701 in the same figure.

61702 is a comparator, 61703, 61704
, 61711 and 61712 are trigger circuits that generate trigger signals by capturing changes in input waveforms (for example, rising edges);
61705.

61706 &'! Reverse reversal AND with force, 6170
7, 61708 are OR, 61709, 61710 are S-R latches that change the output (Q) by setting (S > reset (8), and change by the trigger signal. 617
52 is an input terminal for the aperture value Fv (or other photometric value);
61713 and 61714 are voltage sources Vi, Vj, 6
1755 and 61756 are terminals where detection outputs of aperture values Fvi and Fvj are generated, and 61752 and 61754 are terminals where shutter speed setting signals Tv2 and Tvl are generated. In the circuit of figure (b>), the input device 6110
Connect to encoder 61102 instead of 10, and connect terminal 61
When 752 is H, the shutter speed of Tv2 and terminal 6
When 1754 is H, the shutter speed changes to the shutter speed of Tv1 by a nearly continuous change in shutter speed. Of course terminal 617
A method such as connecting to the shutter speed setting circuit 52 through a converter having a VT output characteristic that changes depending on the output of the shutter speed setting circuit 52 or 61754 may be used.

61753 is a master reset pulse input terminal. To make the explanation clearer, assume that a reset signal is now input to the terminal 51753. This and ts-R latch 6
The output of the S-R latch 61710 is H, and the shutter speed Tvl is selected.

Therefore, the output Fvj of the terminal 61755 is the inverted input row A.
Since the N D 61705 is in the ON state, it is transmitted to the S-R latch 61709 K, but the output Fvi of the terminal 61756 is transmitted to the S-R latch 61710 because the inverting input row A N D 61706 is in the ON state. In the above state, the image is taken at the shutter speed Tv1 shown in Fig. 31 (bl), but the subject becomes brighter and the aperture value becomes Fv1.
Suppose that i has been reached. At this time, the setting of the voltage source Vi61713 and the comparator 61701 cause the terminal 6'1751 to
0 input is compared. This signal is the trigger circuit 6
1703 generates a trigger signal, inverting input row A N
Since D is in the ON state, it is input to the S terminal of the S-R latch 61709, and the terminal Tv2 becomes H. At the same time, this signal passes through the trigger circuit 61711 to the S-R latch circuit 6.
1710 output is AND 61705 with L1 inversion input
and 61706 are in the OFF and ON states. Therefore, the shutter speed changes from Tvl to Tv2, and the terminal 6
The input reception at 1756 becomes the state. In this state, the voltage source Vj 6171 indicates that it has become dark and the aperture value has become Fvj.
4 and continues until it is detected by the comparator 61702.

The operation after detection is the same, so it will be omitted. As described above, according to this embodiment, it is possible to obtain a shutter speed vs. aperture characteristic having the hysteresis characteristic shown in FIG. 31 (bl), and a good AE operation is possible.

Of course, there are other embodiments of such an operation with hysteresis other than the one shown in FIG. 31, and FIG. 33 shows an example of this. Figure 31 (a) shows a wider control range for the aperture for one shutter speed than in Figure 31 (at). In this case, a shift occurs due to the difference between the out-of-plane of the lens and the angle of view of the photometry system.Therefore, to allow for this, the range of change is increased.This, of course, shifts the whole upward as shown in (b). For example, when the metering system is illuminated by light and the lens is photographing a subject, the error becomes large when the shutter speed is high but the subject is dark, and the aperture is not fully opened or extremely large. In this case, the shutter speed is fast, so it is possible to prevent the screen from becoming dark due to insufficient illuminance.

Of course, if the error is large and the shutter speed is high even though the aperture is fully open, the fully open state of the aperture can be easily detected as described above, so if detected, shift the shutter speed to a lower value to prevent malfunctions. Needless to say, it can be resolved. An example in which this fact is actively utilized is shown in FIG. This is a control characteristic suitable for the embodiment shown in FIG. 25 in which the shutter speed is initially set by well output detection. Fvh, Fvt, 'l in the same figure
'vL is the starting point of the auto iris operation after the shutter speed is determined by well output detection. However, since the shutter speed is discrete in this example, it goes without saying that the Fv value may change at points other than the points shown in the figure depending on the subject. Aperture control is performed by opening and closing the aperture along the solid line, but when the subject brightness decreases, the aperture becomes close to opening. If it gets darker and an open state is detected,
As shown by the broken line, the shutter speed Tv is lowered to correct the decrease in brightness.

The AE operation described above approximates the AE characteristics shown in FIG. 30, and of course, if a sufficiently large number of shutter speed settings are used, the same AE characteristics as shown in FIG. 30 can be obtained.

Further, the specifications of each operation of the implementation circuit for realizing each characteristic are clear from the above description and can be easily configured, so the description will be omitted.

In the above explanation, it has been explained that automatic aperture control is performed using an image pickup signal as conventionally done, but of course there is no need to be limited to this, and for example, the automatic aperture control is performed using an image signal, which is output from the terminal 2001 shown in FIG. It goes without saying that the control may be performed using the well output, the output of the photometric circuit 7 shown in FIG. 19, or the like.

An example of this case is shown in FIG. 34 and will be described below. Blocks in this figure having the same numbers as those in FIG. 34 have the same functions. 6222 is a well output detection circuit, which converts the input specifications into input specifications necessary for diaphragm control of the diaphragm control circuit 12 and outputs the same. Since the well output is proportional to the incident light on the shutter-equipped sensor 20, it is clear that aperture control is possible by using this, so the details will be omitted. Further, by dividing the well portion of the photodiode array of the shutter-equipped sensor for obtaining well output and measuring light from each divided well portion, exposure control by so-called multi-photometering is possible. - For example, if the well output of the center part of a 7-otodiode array is used, center-weighted photometry will be performed. It goes without saying that if such control is performed, an effect equivalent to aperture control in which weighting is applied to the imaging output can be obtained.

External photometry can be similarly achieved by dividing or weighting the photometric optical system or photoelectric conversion section.

Furthermore, although the aperture detection has been described as being performed by connecting a potentiometer to the aperture mechanism, it is sufficient to obtain an output corresponding to the aperture value, for example, using a magnetic resistance element.

Of course, detection may be performed using a Hall element or a control drive voltage (or current).

Although the above aperture control has been described as conventional aperture control, that is, closed loop control with a constant time constant, the effects of the present invention are not limited to this. For example, even if the aperture value is not controlled in a closed loop using an imaging signal but in an open loop such as that used in a 35-speed camera, when the shutter speed changes from Tvl to Tv2, Tvt <T
By changing the aperture value according to the change in shutter speed so that the shutter speed Tv is V<TV2, there is of course no change in the brightness of the screen, but there is also a change in the depth of field of the captured image. By changing continuously, images that do not look strange can be obtained, which has the effect of improving usability.

Furthermore, since the aperture value Fv can be detected, it goes without saying that by controlling the shutter speed Tv so that the imaging output is constant, it is possible to perform aperture-priority exposure control in the same manner as manual shutter speed setting. A characteristic diagram showing an example of the aperture priority system in this case is shown in FIG. 35(a). Note that a characteristic diagram of an embodiment of the shutter speed priority method is shown in FIG. 4(b). In each of these characteristic diagrams, exposure control is performed by moving on the characteristic curve on the solid line. If the input setting diagram changes, a dashed line (
or (71) depending on the control characteristics.

In this case, if the shutter speed is continuously changed from Tv (12 to Tv03) while performing auto iris operation, it will change while maintaining the characteristics shown on the broken line or (7).Of course, the shutter speed and aperture value can be separated from the auto iris control. , may be changed by the same change width by feedforward control.

In addition, in the same figure (at), if the subject becomes dark and the proper exposure is not reached, so-called underexposure, the shutter speed should be variably controlled or (to) As shown in the example, all you have to do is change the shutter speed to the next one.If the exposure is overexposed, you can variably control the shutter speed so that an appropriate imaging signal is obtained as shown in ), or as shown in ) All you have to do is change the shutter speed to . Of course, the gain of the signal system may be increased.

The same applies to the shutter priority method, and it goes without saying that the aperture control indicated by bright in underexposure and the aperture control indicated by ()) in case of overexposure are performed. At this time Tv
t31 is shown as the lowest shutter speed.

Note that when performing the controls shown in (Me), (:Ll, and (K) in the same figure, the display indicates overexposure, and when performing the control shown in (1) and (G) in the same figure, displays underexposure. It goes without saying that the operability is further improved if the information is represented by a display means.

Further, the program characteristic curve of the AE control diagram shown in FIG. 30 is an example for explanation, and the present invention is also applicable to other characteristic curves or characteristic curves shifted in the aperture direction and shutter speed direction. Needless to say.

〔Effect of the invention〕

According to the present invention, there is no image disturbance when switching the shutter speed during imaging, and the occurrence of smear is suppressed even during AE operation, so there is an effect that an easy-to-use imaging device with variable shutter speed can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an embodiment for explaining the present invention, Fig. 2 (a1) is a schematic diagram for explaining an embodiment of the sensor used in the present invention, and Fig. 1 (b) is a schematic diagram for explaining an embodiment of the sensor used in the present invention. Schematic diagrams for explaining operations, 3rd and 4th
, 5 is a waveform diagram for explaining the present invention, FIG. 6 is a circuit diagram and waveform diagram showing one embodiment of the present invention, FIG. 7 is a waveform diagram explaining one embodiment of the present invention, and FIG. 8 is a waveform diagram for explaining one embodiment of the present invention. is a block diagram showing an embodiment of the present invention, FIG. 9 is a waveform diagram explaining the same invention, FIG. 10 is a schematic diagram explaining the invention of FIG. 8, and FIG. 11 is an example of the characteristics of FIG. 10. Characteristic diagrams showing 12th and 13th
The figure is a waveform diagram explaining the operation example of Figure 8, 14th and 15th.
The figure is a circuit diagram showing one embodiment, Fig. 16 is a waveform diagram explaining the same embodiment, Figs. 17 and 18 are waveform diagrams and block diagrams showing one embodiment, and Fig. 19 is an embodiment of the present invention. WI20, 21 is a waveform diagram illustrating the same invention, FIG. 22 is a circuit diagram illustrating one embodiment, FIG. 23 is a waveform diagram illustrating the same side, and FIG. 24 is a waveform diagram illustrating one embodiment. Circuit diagram shown,
25 and 26 are block diagrams showing one embodiment of the present invention. and explanatory diagrams, FIG. 27 is a circuit diagram showing one embodiment, and FIG. 28 is a circuit diagram showing an embodiment.
-The figure is a block diagram showing one embodiment of the present invention.
, FIG. 29 is a circuit diagram showing one embodiment, FIG. 30 is a characteristic diagram for explaining the same embodiment, and FIG. 31(a). (bl indicates other embodiments, FIG. 32 indicates FIG. 31(b)
) is one circuit example for explaining the embodiment of FIG. 33 (al
, (c) is another embodiment, FIG. 34 is a block diagram showing one embodiment of aperture control, and FIG. 35 (b) is a characteristic diagram showing another embodiment. 11. ... Trunk, 12... Aperture control circuit, 2
...Sensor with shutter, 31...An7', 32...Process,
33...VTR, 4...Drive circuit, 5...Control circuit, 61...AE circuit, 62...Manual circuit, 62
2...Well output detection circuit, 17...External photometry circuit, 6160...Aperture detection circuit.

Claims (1)

[Claims] 1. A solid-state image sensor having a function of controlling the exposure time of a captured image by varying the accumulation time, which is the time required for photoelectric conversion contributing to an image signal, and the exposure time of the captured image. In an imaging device comprising an exposure time setting means for setting an exposure time T for a function of controlling The exposure time T is T_1≦T_
An imaging apparatus comprising a control means for switching from T_1 to T2 after a third exposure time T_3 satisfying 3≦T_2. 2. An imaging device according to claim 1, further comprising automatic aperture control means for varying the light incident on the solid-state imaging device and keeping the imaging signal output constant. 3. The imaging apparatus according to claim 1, further comprising automatic exposure control means for varying and setting the exposure time T setting value of the exposure time setting means in accordance with brightness information of the subject; Exposure time T_3 set by the exposure control means,
An imaging device characterized in that the exposure time is limited to a time longer than the minimum exposure time T of the exposure time setting means.