JPH0462230B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to an improved imaging device or lighting device that is effective when used in combination with an image sensor having a narrower dynamic range than a silver halide sensor and a lighting device.

(Prior Art) Conventionally, since imaging means such as solid-state image sensors and image pickup tubes have a narrow dynamic range with respect to the brightness of a subject, high precision is required for adjusting the amount of incident light. However, even if such light intensity adjustment is performed accurately, there is a problem in that when strong light enters from a part of the subject, a blooming phenomenon occurs in which carriers overflow over a wide range of the light-receiving surface of the imaging means.

Conventionally, as a countermeasure against this blooming, for example,
It is being considered to provide an overflow drain within the light receiving surface of a CCD image sensor to discharge excess carrier.

However, if such a drain is provided within the light-receiving surface, there is a problem in that the substantial aperture ratio of the light-receiving section is significantly reduced, which hinders resolution improvement. Therefore, an image sensor has been proposed in which blooming is prevented by recombining excess carriers on the sensor surface during the horizontal blanking period, as disclosed in, for example, Japanese Unexamined Patent Publication No. 56-138371.

This type of sensor, as well as the sensor with a drain as described above, is perfect in that blooming will still occur if particularly strong light is concentrated in a short period of time. isn't it.

Further, it is known that such a problem occurs not only when imaging is performed outdoors during the daytime, but also under an illumination light source with a relatively low amount of light.

This is because if a part of the object has a high reflectance, such as a mirror surface, regular reflected light will be incident depending on the angle of illumination, and the light source will form an image on the image sensor.
Of course, if such a highly reflective object has a curved surface, the counter-reflected light will enter the sensor regardless of the illumination angle. The level of such regularly reflected light is hundreds of thousands of times higher in image plane illuminance than that of diffusely reflected light from a general object.

On the other hand, even if exposure adjustment is performed using an automatic diaphragm under a normal illumination light source, or dimming control is performed under a flash illumination light source, these controls are based on average photometry, so regular reflections as described above occur. Blooming caused by light cannot be prevented.

In particular, in image sensors that reduce blooming through surface recombination as described above, each pixel within the light-receiving surface is separated horizontally by a channel stop, so if blooming occurs, the vertical This creates white stripes and significantly degrades the image quality.

Of course, even in an image sensor having an overflow drain, no drain is provided in the horizontal direction, so blooming similarly tends to spread vertically.

Furthermore, when capturing images by incorporating an image sensor into a portable video camera, etc., it is desirable that the illumination light source is also portable.In this case, from the viewpoint of lighting efficiency and portability, the light source should be small, close to a point light source. It is possible that

However, as you get closer to a point light source, the brightness of the light source increases and the level of regular reflected light increases even if the amount of light emitted is the same, so this kind of problem, that is, the problem of blooming due to regular reflected light of illumination light, has been brought into focus. It is clear that

(Objective) It is an object of the present invention to provide an imaging device or a lighting device that can be used with a lighting device that eliminates the drawbacks of the prior art.

In particular, it is an object of the present invention to provide an imaging device that can prevent blooming due to reflected light from an illumination light source.

(Example) The present invention will be explained below based on Examples.

FIGS. 1a to 1c are diagrams showing a first embodiment of the present invention, and FIG. 1a is a diagram showing an example of the configuration of an imaging device.
FIG. 1B is a diagram showing an example of the configuration of an image sensor, and FIG. 1C is a diagram showing an example of the configuration of a color separation filter.

In the figure, 1 is an image sensor as an imaging means as shown in FIG. 1b, for example, and the sensor shown in FIG. 1b is a so-called frame transfer type CCD.
Although the image sensor of the present invention may be an image pickup tube or a MOS/X-Y sensor,
Any device that converts an optical image into electrical information may be used.
1a is a light receiving part, 1b is a light-shielded memory part, 1
c is a horizontal transfer register, 1d is an output amplifier, and the charge accumulated in 1a is transferred to the memory section 1 within the vertical blanking period of the standard television signal.
b at high speed and sequentially read out one horizontal line at a time by the horizontal shift register 1c over the next one field period.

For example, a color stripe filter as shown in FIG. 1c is attached to the light receiving section 1a so as to match the pixel pitch in the horizontal direction.

A driver 2 supplies driving pulses for driving the image sensor 1, and forms the driving pulses in response to a timing signal from a clock generator 3.

Reference numeral 4 denotes an LPF (low pass filter) having a cut-off characteristic of, for example, about 2 MHz, which adds point-sequential outputs from the sensor 1 to form a pseudo luminance signal. The output of the LPF 4 is subjected to various processes such as gamma correction and aperture correction in the process circuit 5.

6 to 8 are sample and hold circuits, respectively;
R (red), G (green), and B (blue) by sampling and holding the point-sequential output of sensor 1 at different phases.
Obtain each color signal. Next, high-frequency components of, for example, 500 KHz or more are cut out by LPFs 9 to 11, and then subjected to various corrections in process circuits 12 to 14, respectively.

The outputs of the process circuits 5 and 12 to 14 are subjected to appropriate modulation in an encoder 15 as a conversion means, and then supplied to a recording head 17 via an analog gate circuit 16 and recorded on a recording medium 18. Further, the output of the encoder 15 is reproduced as a monitor on a television monitor TVM or as a print on a printer PT.
Reference numeral 19 denotes an integrating circuit which outputs a value V ₂ obtained by integrating the output of the LPF 4.

Further, the output V ₂ is also used as a control signal for automatically controlling an aperture (not shown).

20 is a comparator for comparing this output V ₂ with a predetermined reference level, and outputs a low level signal when V ₂ >V ₁ and a high level signal when V ₁ >V ₂ .

The output of this comparator 20 is the delay circuit 3
2, it is used to control ON/OFF of the power switch 22 provided in the power line to the flash light source 21b.

As shown in FIG. 1d, the delay circuit has a one-shot circuit 33 that is synchronized with the rise of the output of the comparator 20, and an R-S flip-flop 36 that is set by the output pulse of this one-shot circuit 33. flip flop 36
The output of a one-shot circuit that forms a pulse synchronized with the fall of the output of the comparator 20 is input to the reset terminal of the comparator 20 via a timer circuit 35.

Therefore, the delay circuit 20 outputs a high level signal from when the output of the comparator 20 rises until a predetermined time period elapses after the output from the comparator 20 falls. Moreover, the switch 22
is ON while the output of this delay circuit is at a high level.
do.

Furthermore, as will be described later, the power switch 22 is turned on.
By doing so, the electrical energy required for flash light emission begins to be accumulated in the light source 21b.

Further, 24 is a coefficient circuit that multiplies the output of the LPF 4 by a predetermined coefficient, and 23 is a comparator as a detection means of the present invention that compares the output V ₂ and the coefficient circuit output V ₃ , such as a coefficient circuit. In
By multiplying the output of the LPF 4 by a coefficient smaller than 1, the comparator 23 detects only signals with particularly high relative levels in the pseudo luminance signal.

Incidentally, the coefficient circuit 24 may be provided within the integrating circuit 19. In that case, the coefficient is set to be larger than 1, for example.

Further, when V ₂ >V ₃ , the comparator 23 outputs a low level, and when V ₂ <V ₃ , it outputs a high level. This high level signal is passed through a delay circuit 33 to a spatial irradiation characteristic control circuit 2 which will be described later.
Basically, while the delay circuit 33 outputs a high level, the light emitting angle or direction of the light source 21b is changed so that the illumination is soft, that is, the area of the light source is apparently expanded.
Here, the configuration of the delay circuit 33 is as follows:
Same as 2.

Further, in this embodiment, the power switch 22 to the flash light source is turned on by the AND gate 25, and
The irradiation characteristic control circuit is switched to the soft side only when the output of the delay circuit 33 is at a high level, but this is to avoid unnecessary control of the irradiation characteristics when the light source is not used.

Further, 26 is an AND gate which inputs the output of the delay circuit 36 and the inverted output of the delay circuit 32 via the inverter 28, and when the integrated value level V ₂ of the pseudo luminance signal is higher than the level V ₁ ,
When the comparator 23 detects a signal with a level extremely higher than this integral level, it outputs a high level.

This high-level output activates the blooming warning circuit 27, which gives a warning to the operator by sound or light. 28 is a trigger circuit for still image recording, and a high level output is obtained from an AND gate 29 in synchronization with the first vertical synchronization signal V _D after the output of the trigger circuit 28 is obtained.

The output of the AND gate 29 is inputted to the trigger terminal T of the light source 21b, so that flash light is emitted immediately after the output pulse of the AND gate 29.

The 0 terminal of the light source 21b is a terminal that outputs a light emission signal in conjunction with a flash light emission operation. AND gate 3 that takes the AND of this light emission signal and the vertical synchronization signal V _D
0, the one-shot circuit 31 forms a pulse with a predetermined time width (for example, 1/60 seconds), and the output of this one-shot circuit opens the gate 16 and guides the output of the encoder 15 to the head 17.

FIG. 2 is a timing diagram of this embodiment, and shows that the power switch of the imaging device (not shown) is turned on.
By doing so, the clock generator 3 forms various pulses at timings synchronized with standard television signals. Based on this pulse, driver 2
The image sensor periodically performs operations such as storage, transfer, and readout using the drive pulses formed by the image sensor. After the high-frequency components of the point-sequential output from the sensor are removed by the LPF 4, the output is multiplied by a coefficient smaller than 1, for example, in the coefficient circuit 24, and the second
The waveform will look like _V3 shown in the figure. On the other hand, the output of the LPF 4 is integrated to form a waveform such as _V2 shown in the second diagram.
As shown in the figure, when the level V ₂ is smaller than the level V ₁ , the output of the comparator 20 becomes high level, and the power switch 2 of the light 21b is switched on via the delay circuit.
2 is included.

In this state, for example, once the value of level _V3 exceeds the value of level _V2 at time _t1 , the output of comparator 23 becomes high level, and the output of delay circuit 33 becomes high level for at least several H (horizontal period).
Thereafter, when the trigger signal is output from the trigger circuit 28 at an appropriate timing (time t ₂ ), the light source 21 b starts emitting light at time t ₄ in synchronization with the vertical synchronization signal V _D from the clock generator 3. It is done.

Note that this light emission timing is selected so that it is not performed within the vertical blanking period in a CCD type image sensor.

During flash photography, the amount of flash light emission is controlled by a light control circuit as described later, and light emission is completed at time _t5 . When this light emitting operation is performed, a high level signal is output from the O terminal of the light source, and in synchronization with the vertical synchronizing signal V _D after outputting this high level signal, the gate 1
6 is open for one field period, and recording on the recording medium 18 is performed.

Note that the rotation of the recording medium 18 is controlled in synchronization with the driving of the image sensor.

In this way, according to this embodiment, it is possible to detect whether or not there is a subject that is likely to cause blooming by simply detecting the state of the output signal without making any changes to the image sensor. It's easy.

In addition, if the overall brightness level of the subject is high, and at least part of it has a relatively high brightness level, a warning is displayed, so you can recognize the presence or absence of blooming even without a TV monitor. .

In addition, since the illumination light source is automatically powered on for a predetermined period of time when the integral level of the luminance signal falls below a predetermined level, the operation is simple and the power saving effect is high.

Further, in this embodiment, the configuration is simple because the image sensor for imaging is also used as a detection means for detecting whether the brightness level of at least a part of the subject image exceeds a predetermined level.

In this embodiment, blooming is confirmed or predicted based on whether or not there is a signal with a deviation value of a predetermined value or more with respect to the luminance integral level, but as a method for obtaining this integral level, simply It is sufficient to simply pass the luminance signal through a low-pass filter, or furthermore, only the low-frequency components of the output of the image sensor may be extracted and used as a pseudo-integral level. Alternatively, the average value of the luminance signal may be calculated using a digital calculation circuit.

Further, in this embodiment, the light source is caused to emit light by ANDing the output of the trigger circuit 28 and the vertical synchronization signal V _D , but a signal related to the stable state of the light source and the spatial irradiation characteristic control circuit (for example, a charge completion signal of the light source) is also used.
It is desirable to logically multiply the values before emitting light.

Further, although the light source 21b is a flash light source in this embodiment, it can also be applied to a continuous light source such as a tungsten light source. Of course, in that case, the power switch 22 becomes unnecessary.

FIG. 3a is a diagram showing a first embodiment of the light source and irradiation characteristic control means according to the present invention, and is a sectional view taken along a plane perpendicular to the flash discharge tube axis. In the figure, 37 is a reflecting mirror, 38 is a front panel (protector), and 39, 39' are flash discharge tubes.

Figure 3c shows the flash discharge tubes 39, 3 in Figure 3a.
9' is a diagram showing the spatial illumination characteristics when only one of the discharge tubes 39 is illuminated, and A is the characteristic when only the discharge tube 39 is illuminated, which is the same as the light emission characteristics of a normal flash device. A' is a characteristic when only the discharge tube 39' emits light, and is a bounce irradiation characteristic.

In this embodiment, a plurality of discharge tubes are arranged at mutually shifted positions within a reflecting mirror having one curve, and different irradiation characteristics are obtained by selecting the discharge tube to emit light. That is, in this embodiment, spatial irradiation characteristic control is achieved by selecting the discharge tube to emit light, changing the irradiation direction, and using bounce lighting to make the light source apparently larger.

FIG. 3b is a diagram showing another embodiment of such irradiation characteristic control, in which each discharge tube is placed within a reflecting mirror having a different diffusion characteristic such as a different curve or a different irradiation angle. This example is the third
The optical system has better performance than the embodiment shown in FIG.

In the illustrated example, the directions of the reflecting mirrors 37 and 37' are changed, but only the curve of the reflecting mirror may be changed, the curve and direction may be changed, or a lens system may be added to the tip of the protector. . Further, a plurality of discharge tubes may be made to emit light sequentially or simultaneously.

FIG. 4 is a diagram showing the electrical circuit of the flash light source used in the embodiment shown in FIG. 3, where V _BB is the power supply and 22
is the power switch, 100 boosts the DC voltage
DC-DC converter, 101 is a diode, 10
2, 102' is a known discharge tube trigger circuit, which includes husband and wife resistors 108, 108', 112, 11.
2', thyristor 109, 109', capacitor 1
It consists of 10, 110' transformers 111, 111', etc.

106 is a diode connected in series in the opposite direction to the discharge tubes 39, 39' and connected in parallel to the inductor 105; 119 is a light amount control circuit and is a commutating capacitor 123;
3 charging resistors 128, 122, thyristor 12
0, 126 resistance 121, 125, 127, resistance 1
The capacitor 124 is connected to the gate of the thyristor 120 via a capacitor 25. 113 is a main capacitor for causing the discharge tubes 39, 39' to emit light; 103, 103' are two-input AND gates, one input of which is both connected to the trigger input terminal T; Further, a signal from an irradiation characteristic control input terminal 104 is input to the other input terminal of the gate 103 via an inverter 107.
Further, a signal from the control input terminal 104 is input to the other input terminal of the gate 103'. Also, 117
11 is a light receiving element that receives reflected light from a subject;
6 is an integral capacitor charged in accordance with the photocurrent from the light receiving element 117, 114 and 115 are voltage dividing resistors, and 118 is a comparator for turning on the thyristor 126.

Further, TC is a timer that outputs a high level pulse of a predetermined width when the potential at the connection point between the resistor 122 and the discharge tube is high.

Next, the operation will be explained.

When the switch 22 is turned on by the output of the delay circuit 32 shown in the first diagram, the DC-DC converter 10
0, the voltage of the power supply _VBB is boosted and applied to the capacitor 113 via the diode 101, thereby charging the capacitor 113.

Next, when the charging voltage of the main capacitor 113 reaches a sufficiently high value for light emission, a high level signal from the AND gate 29 shown in FIG. One of the thyristors 109 and 109' is turned on depending on whether the signal to be output is low level or high level.

For example, when a high level is input to the input terminal 104, that is, when a signal for softening the irradiation characteristics is input, the thyristor 109' is turned on.
do. Then, the charge stored in the capacitor 110' flows through the closed circuit on the primary side of the transformer 111', and a high voltage pulse of several KV is applied to the trigger electrode of the discharge tube 39', causing the discharge tube 39' to emit flash light. Let's do it.

Correspondingly, the potential at the connection point between the resistor 122 and the discharge tube increases immediately before the flash is emitted, so a high level signal is output to the O terminal for a predetermined period of time via the buffer TC. The reflected light from this emission is transmitted to the light receiving element 11.
7, and since a current flows through the light receiving element according to the subject brightness, the potential level across the capacitor 116 that integrates this current is determined by the resistor 11.
When the predetermined level determined by 4 and 115 is reached, a high level signal is output from the comparator 118.
This signal turns on the thyristor 126, so the charges stored in the capacitors 123 and 124 are discharged, and the cathode of the thyristor 120,
Reverse bias between the anodes and the gate input terminal.
This turns off the thyristor 120 and stops the discharge tube 39' from emitting light.

According to the embodiment of the present invention described above, when there is a subject where blooming is likely to occur, the spatial illumination characteristics of the light source are controlled by switching the illumination direction of the light source, so bounce illumination is performed, and the light source The apparent size of the image becomes very large, and even if a mirror surface exists, the effect of suppressing blooming becomes very large.Moreover, in principle, the image plane exposure does not change, so the exposure for the entire subject becomes appropriate. .

Conversely, if there is no subject that is likely to cause blooming within the angle of view, the illumination direction is directed directly toward the subject, so that the illumination light efficiently illuminates only the main subject. Therefore, the power saving effect is greater than that which can only be achieved by bounce lighting.

Next, FIG. 5 is a diagram showing another example of the spatial irradiation characteristic control circuit of the present invention.
A type of liquid crystal 129 is arranged, thereby changing the irradiation direction as a spatial irradiation characteristic of the light source.

In FIG. 5, the same numbers as in FIG. 4 indicate the same elements.

132 is a transistor that is turned on by a high level signal from the spatial irradiation characteristic control input terminal 104; 130 and 131 are voltage dividing resistors; and 132 is a capacitor for stabilizing the voltage division.

With this configuration, when a high level signal is applied to the terminal 104, the liquid crystal 129 has irregular molecular arrangement and becomes cloudy. As a result, discharge tube 3
The light emitted from 9 is diffused and the level of regularly reflected light from mirror surfaces etc. can be reduced.

In the case of this embodiment, only one light source is required, and the configuration for controlling the switching of spatial illumination characteristics is very simple.

FIG. 6 is a diagram showing another configuration for confirming and predicting blooming according to the present invention.

This embodiment is suitable for an image sensor having an overflow drain within the light-receiving surface.
The detection sensitivity of the detection means is increased by making overflow more likely to occur in a mode using a light source, and the spatial illumination characteristics of the light source are changed when overflow occurs at this time.

In the figure, 40 is an overflow drain provided in the light receiving section 1a, and is arranged adjacent to the pixels of the light receiving section via an overflow barrier.

Each overflow drain is connected to power supply potential Vcc via a resistor 47. Reference numeral 49 denotes a comparator as a detection means that switches the output state when the signal V ₄ corresponding to the amount of current flowing through the resistor 47 exceeds a predetermined level Vref. Normally, the signal V ₄ contains only noise components. However, by setting the value of the level Vref to a value slightly larger than the upper limit level of the noise component, it is detected whether or not this noise component includes an overflow component. If an overflow component is included, the comparator 49 outputs a high level signal, which is converted by the delay circuit 50 into a high level pulse of a predetermined duration. This delay circuit 50 is, for example, the delay circuit 32 shown in FIG.
It has the same configuration as . The output of this delay circuit 50 is displayed by sound or light in a display circuit 52, and a switch 5 which is linked to the power switch of the light source is displayed.
3 and the AND gate 51 and used for characteristic control by the spatial irradiation characteristic control circuit 21a. 61 is an inverter, 62
is an AND gate and turns on power switch 22.
By doing so, the switch 43 is switched to the b side from when the illumination mode is selected and the light source enters the standby state until a charging completion signal is obtained from the O terminal of the light source.

While the switch 43 is on the contact a side, the output of the LPF 4 shown in FIG. As a result, the diaphragm is servo-controlled so that the integral level of the luminance signal passed through the LPF 4 is always constant. On the other hand, in the lighting mode, as mentioned above, switch 4 is turned off until charging is completed.
Since the contact No. 3 is switched to the b side, the output value of the integrating circuit 19 is converted to a predetermined correction level value by the subtracting circuit 44.
It is subtracted by _V5 and then input to the aperture control circuit.

Therefore, the aperture tends to overexpose the image. Therefore, if there is relatively strong reflected light in the subject, the carrier will overflow at that position within the screen and will be guided to the power supply Vcc via the overflow drain. At this time, since the potential V ₄ changes, the comparator 49 outputs a high level, and the irradiation characteristic control circuit 2
1a switches the spatial illumination characteristics of the light source 21b to the soft side. It is assumed that the automatic iris and other diaphragm control is performed in the range from the fully closed state of the diaphragm to the diaphragm position that is one or two stops narrower than the fully open state.

As described above, according to this embodiment, by slightly opening the aperture in the mode using the illumination light source, the sensitivity of the detection means is increased, such as by making it easier for overflow to occur in the image sensor, and when overflow is detected in that state. Since this is displayed and the spatial illumination characteristics of the light source are switched to the soft side or the diffuse side, it is easy to see whether there is an object with a relatively high reflectance within the imaging screen.

In addition, without making any changes to the image sensor itself, it is possible to know which objects in the subject are likely to overflow, and if such objects occur, the spatial illumination characteristics will be automatically softened. blooming can be suppressed.

In this embodiment, in the illumination mode, the light-receiving part of the image sensor is overexposed by the aperture, but for example, if a rotary shutter is used as the shutter, the aperture angle may be opened by a predetermined amount. Needless to say, it's good to do what you do.

In that case, it is sufficient to simply replace the diaphragm 41 in FIG. 6 with a rotary shutter and the diaphragm control circuit with an opening angle control circuit of the rotary shutter.

Of course, both the shutter and the aperture may be controlled to the overexposure side.

In this embodiment, when the charging of the light source 21b is completed, the switch 43 is returned to the a side, so that the aperture is returned to an appropriate value, and imaging using illumination light is performed in an appropriate exposure state.

Furthermore, in this embodiment, the characteristics of the light source are changed by detecting the signal flowing into the overflow drain when the exposure is over-exposed, but even if an overflow drain is not used, the image sensor generally has a channel stop in the horizontal direction. Alternatively, since it is partitioned by an anti-blooming barrier, when blooming occurs, the carrier overflows in the vertical direction rather than the horizontal direction.

This tendency is particularly strong in image sensors that do not have an overflow drain, as shown in FIG. 7b.

FIG. 7a is a diagram showing another embodiment of the present invention, in which blooming in the vertical direction is controlled by blooming in the horizontal direction that is adjacent to the light receiving section in the vertical direction.
Detection is performed using a CCD array, and the same effect as the device shown in FIG. 6 can be obtained.

That is, blooming as shown in Figure 7a.
When BLM occurs, carriers overflow, especially in the vertical direction. Reference numeral 1e denotes a light-shielded horizontal shift register for blooming detection according to this embodiment that detects this vertical overflow, and when blooming is not occurring at all or is hardly occurring, the register 1e is Only the dark current is formed.

However, once blooming occurs, a large level of carrier enters a given cell within this register. Therefore, if this horizontal shift register is always driven at high speed, the carriers that overflow in the vertical direction immediately after blooming are outputted as a voltage signal to the output amplifier 1f and can be detected.

54 and 55 are CRs for integrating the dark current level
This is an integrating circuit, and 56 is a comparator that compares the output of this integrating circuit with the direct output of the output amplifier 1f, and outputs a high level signal when a particularly large level signal is present in the output from the register 1e. do. Reference numeral 57 is a delay circuit that maintains this high level output, and has the same configuration as that shown in FIG. 1d, for example. This delay circuit 57
The output is supplied via a terminal 58 to one input of the display circuit 52 or the AND gate 51 shown in FIG.

With this configuration, blooming can be easily detected, and since there is no need to provide an overflow drain, the number of horizontal pixels can be increased.

Note that instead of providing the overflow drain, a transparent electrode may be provided in the light receiving section near the surface of the light receiving section for recombining the overflow carrier with the other carrier.

Such an electrode configuration is described, for example, in the above-mentioned Japanese Patent Application Laid-Open No. 56
- Shown in Publication No. 138371, etc. In this way, excess carrier can be eliminated to a certain extent within the light receiving section.

Note that if the boundaries between each pixel 60 are formed by channel stops 59 as shown in FIG. 7b, even if blooming occurs, overflowing carriers will only overflow in the vertical direction, so that the blooming detection shown in FIG. The sensitivity of the configuration is further improved.

Incidentally, in the above embodiments, an excessive brightness level in at least a part of the subject is detected by the imaging means that forms an imaging signal for electrically recording or reproducing the subject image. The present invention provides a plurality of photoelectric conversion elements separately from the imaging means,
It also includes a device in which the detection is performed by forming an image on the plurality of photoelectric conversion elements that is substantially the same as the object image formed on the light receiving surface of the image pickup means.

Further, in this case, the number of the plurality of photoelectric conversion elements may be smaller than the number of pixels on the light receiving surface of the imaging means.

(Effects) As explained above, according to the present invention, when the level of the signal formed in each part of the light receiving surface exceeds a predetermined level, the spatial irradiation of the light source for illuminating the subject is performed. By controlling the characteristics to further diffuse the light, blooming can be significantly suppressed. Furthermore, when there is no subject that is likely to cause blooming, the illumination efficiency is improved by suppressing the diffusivity of the illumination light, so that the power source can be used effectively.

[Brief explanation of drawings]

FIG. 1a is a diagram showing an example of the configuration of an imaging device according to the present invention, FIG. 1b is a diagram showing an example of an image sensor, FIG. 1c is a diagram showing an example of a color filter, and FIG. A diagram showing an example of the configuration of the circuit 32, FIG. 2 is a timing diagram of the circuit shown in the first diagram, and FIG.
Fig. 3a shows an example of the spatial irradiation characteristic control means of the present invention, Fig. 3b shows another example of the spatial irradiation characteristic control means, and Fig. 3c shows the switching state of the spatial irradiation characteristics. FIG. 4 is a diagram showing a configuration example of the illumination device and spatial illumination characteristic control circuit of the present invention,
FIG. 5 is a diagram showing another example of the configuration of the illumination device and the spatial illumination characteristic control circuit, FIG. 6 is a diagram showing another embodiment of the imaging device of the present invention, and FIG. 7a is a diagram showing the detection means of the present invention. FIG. 7b is a diagram showing an example of the configuration of an image sensor. 1...Image sensor, 19...Integrator circuit, 2
3...Comparator as a detection means, 21b...
. . . Light source, 21a . . . Spatial irradiation characteristic control circuit.

Claims (1)

[Scope of Claims] 1. Imaging means for photoelectrically converting imaging light from a subject; detection means for detecting the brightness level of the subject; illumination means for illuminating the subject; and detection means and a control means for varying the spatial illumination characteristics of the illumination means based on the detection output of the imaging apparatus. 2. The imaging device according to claim 1, wherein the spatial illumination characteristic is a direction or angle characteristic of illumination. 3. A light emitting means for illuminating the subject; a means for variably setting the spatial illumination characteristics of the illumination light emitted by the light emitting means; and controlling the spatial illumination characteristics according to the brightness level of the subject. A lighting device characterized by comprising a control means for controlling.