JP2000069356A - Image pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce errors between a proper exposure level and an exposure level of a photographed image. SOLUTION: An exposure control value arithmetic section 201 calculates proper exposure level, based on luminance of the object detected by a photometry section 3, and the opening amount of an aperture 12 and the exposure time of a CCD 10 are controlled, based on the proper exposure level to conduct photographing. Image data outputted from the CCD 10 are stored in an image memory 18, and an exposure level arithmetic section 202 calculates the exposure level of a photographed image using the image data, and a correction gain arithmetic section 203 calculates the gain for correcting the exposure level of the photographed image to a proper exposure level. Then a level correction section 19 amplifies the image data by a correction gain for correcting the level. Error with respect to proper exposure level is reduced by correcting the exposure level of the photographed image through image processing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image pickup apparatus which photoelectrically converts a subject light image into an image signal and takes in the image signal.

[0002]

2. Description of the Related Art FIG. 10 is a diagram showing a basic block configuration of a digital camera provided with a conventional imaging device.

In the conventional digital camera 100, when a release is instructed by the shutter button 103, the TTL
(Through-the-lens) The luminance Bv of the subject is detected by the photometric unit 102 having a photometric element, and based on the detection result, the control unit 101 controls the aperture 105 provided in the taking lens 104 (in FIG. , Drawn outside the lens) and the CCD (Charge C) as an image sensor.
The exposure time Tv (time corresponding to the shutter speed) of the Oupled Device 106 is set, and the aperture 105 is set to a predetermined opening amount by the aperture driving unit 110 based on the aperture value Av. CC
D106 is driven for a time corresponding to the exposure time Tv, and exposure control (photographing) is performed. When the imaging operation of the CCD 106 is completed, the accumulated charges (pixel signals) are read from the CCD 106, converted into digital signals by the A / D converter 107, and further processed by the image processing unit 108 such as white balance and γ correction. After a predetermined image processing is performed, the image is recorded on a memory card 109 as a recording medium.

That is, in the conventional digital camera 100, the level (exposure level) of an image signal picked up by the CCD 106 may be changed as a whole by image processing, but the relative level between pixels is adjusted. The data is recorded on the memory card 109 without any change (that is, while maintaining the luminance distribution captured by the CCD 106).

[0005]

Incidentally, in a digital camera using a TTL photometric element, an error is output from the CCD due to an error factor such as a photometric error of the TTL photometric element, an error in aperture control, and an error in exposure control of the CCD. The exposure level of the picked-up image does not match the ideal exposure level, and a slight error occurs. Therefore, the captured image is overexposed or underexposed to an ideal exposure level. Therefore, conventionally, the exposure level error characteristic is generally measured in advance for each camera and stored in a memory or the like, and the exposure control value is corrected based on the error characteristic at the time of photographing to reduce the exposure level error. That is being done.

However, since the error characteristic set for each camera is obtained by averaging the variation in the exposure level error caused by repeated shooting, each exposure control value set for each shooting is corrected by the error characteristic. Even so, a slight error based on the individual difference of the camera will remain.

Further, in a type such as a single-lens reflex camera, in which a camera is constructed by arbitrarily combining a camera body and a photographing lens, an error factor occurring on the camera body side and an error factor occurring on the photographing lens side are combined. Only then will the error characteristics of the camera be determined,
It is difficult to measure the error characteristics for all combinations in advance, and it is not practical. Therefore, the error characteristics are not determined according to the combination of the camera body and the photographing lens.

[0008] Even in a single-lens reflex camera, the error characteristics are measured in advance, and there is no method for reducing the error of the exposure level based on the error characteristics. The error characteristics of the camera body are calculated by averaging the error variations that occur, and the error characteristics of the lens are calculated by averaging the error variations that occur on the taking lens side for each lens type. Since the error characteristics of both will be determined according to the combination of lens types,
Even if individual exposure control values set for each photographing are corrected with error characteristics determined according to the combination of the camera body and the photographing lens, the individual differences between the cameras may be affected as in the case of the above-described lens-integrated camera. A small error will remain.

Therefore, in the conventional digital camera, as shown in FIG. 10, since the exposure level of the image signal output from the CCD 106 is the exposure level of the recorded image as it is, the image signal output from the CCD 106 If the exposure level of contains the above error,
The exposure level of the recorded image is overexposed or underexposed with respect to the ideal exposure level.

The present invention has been made in view of the above problems, and provides a digital camera capable of reducing an error in the exposure level of a recorded image from an ideal exposure level.

[0011]

SUMMARY OF THE INVENTION The present invention provides a photoelectric conversion means for converting a subject light image into an image signal by photoelectric conversion, a brightness detection means for detecting the brightness of the subject, and calculating an appropriate exposure level based on the brightness of the subject. First calculating means for calculating an exposure control value of the photoelectric conversion means based on the appropriate exposure level, and photoelectric conversion based on the exposure control value calculated by the second calculating means. Exposure control means for controlling the exposure amount of the means, third calculation means for calculating the exposure level of the image signal output from the photoelectric conversion means, and correction for correcting an error between the proper exposure level and the exposure level A fourth calculating means for calculating the amount; and a correcting means for correcting the exposure level of the image signal using the correction amount (claim 1).

According to the above arrangement, the brightness of the subject is detected by the brightness detecting means, the first calculating means calculates the proper exposure level based on the detection result, and the second calculating means calculates the proper exposure level based on the proper exposure level. An exposure control value of the photoelectric conversion means is calculated. Then, the exposure amount of the photoelectric conversion unit is controlled by the exposure control unit based on the exposure control value, and a subject image is captured.

The image signal output from the photoelectric conversion means is:
The third calculation means calculates the exposure level, and the fourth calculation means calculates a correction amount for correcting an error between the exposure level and the proper exposure level. Then, the exposure level of the image signal output from the photoelectric conversion unit is corrected by the correction unit using the correction amount calculated by the fourth calculation unit.

In the image pickup apparatus, the exposure control means may be constituted by an exposure time control means for controlling an exposure time of the photoelectric conversion means. Further, the exposure control means may be composed of a light quantity control means for controlling the quantity of light incident on the photoelectric conversion means and an exposure time control means for controlling the exposure time of the photoelectric conversion means.

According to the former configuration, the subject image is captured by controlling the exposure time of the photoelectric conversion means based on the exposure control value calculated by the second calculation means. According to the latter configuration, the amount of light incident on the photoelectric conversion unit is controlled based on the exposure control value calculated by the second calculation unit (for example, the stop amount of the stop is controlled), and the exposure of the photoelectric conversion unit is controlled. The subject image is captured by controlling the time.

[0016]

FIG. 1 is a perspective view showing an appearance of a digital camera provided with an imaging device according to an embodiment of the present invention.

The digital camera 1 has a photographing lens 2 disposed substantially at the center of the front surface thereof, and a photometric unit 3 for detecting the luminance of the subject is provided above the photographing lens 2. A photometric unit for measuring the subject distance is located on the left side of the photometric unit 3. A flash unit 5 is provided on the distance unit 4 and on the right side of the photometric unit 3. A finder objective window 6 is provided on the left side of the distance measuring unit 4.

The photometric unit 3 has a light receiving element such as an SPD, and receives light reflected from the subject to detect the brightness of the subject.
FIG. 2 shows an embodiment of the configuration of the light receiving elements of the photometric unit 3, in which nine light receiving elements s1 to s9 are arranged in a 3 × 3 matrix on the light receiving surface 301. Further, as shown in FIG. 3, the photometric unit 3 has a photometric area A1 at the center with respect to the photographing screen A0, and the light reflected from the subject included in the photometric area A1 has nine light receiving elements. s1 ~
Each is received at s9.

The levels of the light receiving signals output from the light receiving elements s1 to s9 are represented by Bv1, Bv2,.
[V], subject brightness BvC used for exposure control
Is detected using the light receiving levels Bv1 to Bv9, for example, by calculation using the following equations (1) and (2).

The expression (1) indicates that nine light receiving levels Bv1,
Bv2,..., Bv9 are simply averaged, and a method of detecting this simple average value as the subject brightness BvC [v] is called an average photometry method. Equation (2) is for weighting the light receiving level Bv5 of the central light receiving element s5 and performing weighted averaging. This weighted average is used as the subject brightness BvC [v].
Is a method called center-weighted photometry.

[0021]

(Equation 1)

In this embodiment, the photometric area A1
Although nine photometric elements a1 to a9 are arranged in a matrix, the number and arrangement pattern of the photometric elements are not limited to this.

The distance measuring section 4 measures an object distance by, for example, an active distance measuring method. A light emitting element for irradiating the object with infrared light and a light receiving element for receiving reflected light of the infrared light from the object are provided. And detecting the distance from the camera to the subject based on the angle of reflection of the infrared light on the subject.
Although the active ranging method is adopted as the ranging method, a passive ranging method may be used.

On the side of the digital camera 1, there is provided a card insertion slot 7 into which a memory card 11 is inserted and removed. A card ejection button 8 for ejecting the memory card 11 inserted above the card insertion slot 7 is provided. Is provided. When the photographing result is printed out, the memory card 11 can be detached from the digital camera 1 by pressing the card removal button 8 and can be mounted on a printer to which the memory card 11 can be mounted and printed out.

The digital camera 1 is provided with an interface of a SCSI cable, and the digital camera 1 is connected to the printer with a SCSI cable to directly transmit image data (each of a plurality of pixels constituting an image) from the digital camera 1 to the printer. (Data composed of data) may be transferred to print out the photographed image. Also,
In this embodiment, PCMC is used as a recording medium for image data.
Although an IA-compliant memory card is used, another recording medium such as a hard disk card or a mini disk (MD) may be used as long as the imaging result can be stored as image data.

A shutter button 9 for instructing photographing is provided at the left end of the upper surface of the digital camera 1. Although not shown, a main switch and a finder eyepiece window are provided on the rear surface of the digital camera 1.

Further, an image sensor 10 is provided in the camera body at a position behind the photographing lens 2. Image sensor 10
Is R (red), G in Bayer method as shown in FIG.
(Green) and B (blue) color filters are configured by a single-plate type color CCD (Charge Coupled Device) provided for each pixel g. Note that the image pickup device 10 may be configured by a three-plate type color CCD.

FIG. 2 is a block diagram of a digital camera 1 provided with an image pickup apparatus according to the present invention. In the figure, the same members as those described above are denoted by the same reference numerals. The imaging apparatus according to the present invention basically includes a photographic lens 2, a photometry unit 3, an imaging element 10 (hereinafter, referred to as a CCD 10), an aperture 12, and a level correction unit 19.

The aperture 12 adjusts the amount of light incident on the CCD 10. In the figure, the photographing lens 2 and the CCD 10
Although the aperture 12 is drawn between the two, the aperture 12 is disposed in the taking lens 2 in an actual configuration.

The A / D converter 13 converts an image signal (analog signal) output from the CCD 10 into a digital signal. Further, the lens driving unit 14 is a
The focus adjustment is performed by controlling the driving of the camera. The lens drive unit 14 moves the photographing lens 2 to a focus position based on control data (drive amount data) input from the control unit 20. The aperture drive unit 15 controls the aperture of the aperture 12. The aperture driving unit 12 sets the aperture of the aperture 12 to a predetermined aperture amount based on control data (aperture amount data) input from the control unit 20.

The timing controller 16 controls the A / D converter 13 to read the image of the CCD 10 and read the image signal.
A timing pulse for performing each operation of conversion is generated. The timing control unit 16 has a reference clock, divides the frequency of the reference clock, generates a timing pulse of a predetermined frequency, and inputs the timing pulse to the CCD 10 and the A / D converter 13, respectively. Further, the timing control section 16 generates a timing signal (exposure control signal) for starting / ending the exposure operation of the CCD 10 based on the control signal from the control section 20 and inputs the signal to the CCD 10.

The image processing section 17 has a signal processing circuit such as a black level correction circuit, a white balance circuit, and a γ correction circuit, and corrects the black level of the image data output from the A / D converter 13 and adjusts the white balance. It performs predetermined signal processing such as adjustment and gradation correction.

The image memory 18 has a RAM (Random Access).
Memory), and temporarily stores image data output from the image processing unit 17. Level correction unit 1
Numeral 9 is for correcting the level of the captured image (image data stored in the image memory 18). This level correction is performed to correct the exposure level of the photographed image due to various error factors such as a photometric error of the luminance of the subject in the photometric unit 3, a control error of the aperture amount of the aperture 12, and a control error of the exposure time of the CCD 10. This is a correction of the error with respect to the level. The level correction unit 19 performs level correction of the image data read from the image memory 18 based on the correction gain input from the control unit 20. The level correction will be described later.

The control section 20 controls the photographing operation of the digital camera 1 in a centralized manner. The control unit 20 is composed of a microcomputer, and includes the photometric unit 3, the distance measuring unit 4, the lens driving unit 14, the aperture driving unit 15, and the timing control unit 1 described above.
6 to control the imaging operation, and also controls the driving of the image processing unit 17, the image memory 18, and the level correction unit 19 to control the recording operation of the captured image on the memory card 11.

The control unit 20 includes an exposure control value calculation unit 20.
1. Exposure level calculator 202 and correction gain calculator 20
3 is provided. The exposure control value calculation unit 201 uses the photometry data input from the photometry unit 3 to set an appropriate exposure level Ev
[Ev] is calculated, and an exposure control value (aperture value Av [Ev] of the aperture 12 and CC
D10 exposure time (time corresponding to shutter speed)
Tv [Ev]). The data of the aperture value Av and the exposure time Tv calculated by the exposure control value calculation unit 201 are output to the aperture drive unit 15 and the timing control unit 16, respectively, and the data of the appropriate exposure level Ev are input to the correction gain calculation unit 203. You.

The exposure level calculator 202 calculates the exposure level AveC [v] of the photographed image.
The exposure level AveC calculated by the exposure level calculation 202 is input to the correction gain calculation unit 203. Further, the correction gain calculator 203 calculates the appropriate exposure level K [v] (the value obtained by converting the Ev value into a voltage value) calculated by the exposure control value calculator 201 and the exposure level AveC calculated by the exposure level calculator 202. And a gain α (= K / AveC) for correcting the exposure level AveC to the appropriate correction level K is calculated. The gain α will be described in the photographing control described later.

Next, the photographing operation of the digital camera 1 according to the present invention will be described with reference to the flowchart shown in FIG.

When the shutter button 9 is pressed (Y in # 1)
ES), the control unit 20 drives the photometric unit 3 and captures photometric data (# 2). This photometric data is obtained from the light receiving elements s1 to s
The light receiving signals Bv1 to Bv9 output from the light receiving unit 9 are A / D converted. The light receiving signals Bv1 to Bv9 input from the photometry unit 3 to the control unit 20 are A / D converted by the exposure control value calculating unit 201.

Subsequently, in the exposure control value calculator 201, the subject brightness BvC is calculated by a predetermined calculation formula (for example, the above formulas (1) and (2)) using the photometric data Bv1 to Bv9, and the subject brightness BvC is calculated. , The exposure control value (the opening amount Av of the aperture 12 and the exposure time Tv of the CCD 10) is calculated (# 3).

The exposure control values Av [Ev], Tv [Ev]
If the sensitivity corresponding to the film sensitivity of the silver halide film of the CCD 10 is Sv [Ev], the appropriate exposure level Ev is obtained from the apex value of the subject brightness BvC and this sensitivity Sv.
(= BvC + Sv) [Ev] is calculated, and is determined using the appropriate exposure level Ev, a preset exposure level Ev, and a program chart showing the relationship between the aperture Av and the exposure time Tv.

Subsequently, the control unit 20 calculates the calculated opening amount Av.
Is output to the aperture driving unit 15 and the aperture driving unit 1
After setting the aperture 12 to a predetermined opening amount Av via the interface 5 (# 4), the data of the exposure time Tv [sec] is output to the timing control unit 16 to perform the imaging operation of the CCD 10 (#
5). That is, the timing control unit 16 starts the charge accumulation (exposure) of the CCD 10 at a predetermined timing, and stops the charge accumulation when the exposure time Tv has elapsed.

Subsequently, when the charge accumulation of the CCD 10 is completed, the timing controller 16 outputs a timing pulse of a predetermined frequency to the CCD 10 and the A / D converter 13 to read out the charge accumulated in each pixel g ( # 6). CCD
The accumulated charges read from 10 (that is, image signals)
Is converted into a digital signal (image data) by an A / D converter 13, subjected to predetermined image processing by an image processing unit 17, and then temporarily stored in an image memory 18.

Subsequently, the control unit 20 calculates a gain α for exposure level correction using the image data stored in the image memory 18 (# 7). The gain α for exposure level correction is calculated according to the calculation procedure of FIG.

First, as shown in FIG. 8, the exposure level calculator 202 extracts areas a1 to a9 corresponding to the light receiving areas of the respective light receiving elements s1 to s9 of the photographed image G0, and extracts the respective areas a1 to a9.
Exposure levels Aa1 to Aa9 representing a9 are calculated (#
21). As shown in FIG. 9, R,
Pixel data D _Ri (h, k) of each color component of G and B (h = 1,3, ... m-
1, k = 1,3, ... n-1), D _Gi (h, k) (h = 1,2, ... m, k = 1,2, ...
n, where h + k = odd number, D _Bi (h, k) (h = 2,4, ... m, k =
2,4, ... n), the exposure level Aai (i = 1,
2,... 9) are, for example, the respective areas ai (i = 1,
2,... 9), a simple average value Avei of all pixel data D _Ri (h, k), D _Gi (h, k), and D _Bi (h, k) of each of the R, G, and B color components.
Is calculated as

[0045]

(Equation 2)

The CCD 10 is a three-plate color CCD.
In this case, there are three images of each color component of R, G, and B, and regions a1 to a9 are extracted from the image of each color component. Since the pixel data D _Ri (h, k), D _Gi (h, k), and D _Bi (h, k) of each color component are respectively n × m, Aai = Avei = [(D _Ri (1,1 ) + D _Ri (1,2) +… D _Ri (m, n) + (D _Gi (1,1) + D _Gi (1,2) +… D _Gi (m, n) + (D _Bi (1 , 1) + D _Bi (1,2) +... D _Bi (m, n)] / 3 (m · n).

As a method of calculating the exposure level Aai, a simple average of pixel data extracted at a ratio of one pixel to several pixels may be calculated instead of all pixel data of R, G, and B color components. , G may be calculated as a weighted average. Alternatively, a simple average of all pixel data of the G color component may be calculated.

Subsequently, nine exposure levels Ave1, Ave2,
... Ave9 is used to calculate an exposure level AveC [v] for all areas a0 of areas a1 to a9 (# 22). The calculation of the exposure level AveC is also performed by the calculation formula (1) of the subject brightness BvC,
Similar to (2), it is calculated by the following equations (4) and (5).

[0049]

(Equation 3)

The exposure level AveC indicates the exposure level of the captured image, and the photometric value of the photometric unit 3 and C
If no error occurs in the exposure control of the CD 10 and the aperture control of the aperture 12, the aperture value Av is determined based on the subject brightness BvC.
And the exposure time Tv are set.
veC = K (appropriate exposure level). However, actually, an error occurs in any of the elements related to the exposure control, and Ave
In general, C ≠ K. The gain α for exposure level correction indicates a signal amplification factor for adjusting the exposure level so that AveC = K when AveC ≠ K.

Therefore, once the exposure level AveC is calculated, the gain α for exposure level correction is calculated (# 23). This gain α is calculated by α = K / AveC.

If the gain α for the exposure level correction is too large, the corrected image may cause a gradation drop or a decrease in S / N. Therefore, when the calculated gain α exceeds a predetermined range. It is preferable to limit the set value by the maximum value or the minimum value of the range. That is, when Th1 ≦ K / AveC ≦ Th2, α = K / AveC When K / AveC <Th1, when α = Th1 Th2 <K / AveC, the gain α may be calculated by an arithmetic expression of α = Th2.

When K / AveC is within the small range δ, the gain α may be set to 1 so that the exposure level is not substantially corrected.

Returning to FIG. 6, when the gain α is calculated, the control unit 20 sets the gain α in the level correction unit 19 (# 8). Subsequently, the pixel data is read out from the image memory 18 (# 9), and the level of each pixel data is amplified by the gain α by the level correction unit 19 and is sequentially recorded on the memory card 11 while performing the level correction (# 9 to # 9). # 12 loop).
When the recording of all the pixel data on the memory card 11 is completed (YES in # 12), the photographing process is terminated,
The process returns to step # 1 to perform the next photographing process.

As described above, the exposure level A
veC is calculated, and the level of the pixel data constituting the captured image is calculated by the ratio α (= K / AveC) between the exposure level AveC and the appropriate exposure level K calculated based on the subject luminance Bv detected by the photometry unit 3. Since the exposure level of the captured image is adjusted to the proper exposure level, errors occur in the photometric value of the photometric unit 3, the exposure control of the CCD 10, and the aperture control of the aperture 12, and the exposure level of the captured image becomes the appropriate exposure level. In the case where it is different from the above, the error is corrected, and the exposure level of the captured image can be set to an appropriate level.

In the above embodiment, a digital camera has been described as an example. However, the present invention is not limited to this. A still image is captured using a photoelectric conversion element, and a predetermined process is performed on the still image. (For example, a scanner, a digital copier, or a camera,
It can be widely applied to a film image reproducing apparatus that reproduces on RT or the like or prints on recording paper.

[0057]

As described above, according to the present invention, in an imaging apparatus for capturing a subject image by photoelectrically converting it into an image signal, an exposure level is calculated from an image signal constituting a captured image, and the exposure level and the exposure level are calculated. A level correction amount is calculated from an appropriate exposure level when controlling imaging, and the exposure level of the captured image is corrected using the level correction amount. Therefore, aperture control and exposure based on the appropriate exposure level in imaging control are performed. Even when an error occurs in the control, the error can be corrected and a captured image with a suitable exposure level can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an appearance of a digital camera including an imaging device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating an embodiment of a configuration of a light receiving element of a photometry unit.

FIG. 3 is a diagram illustrating a photometry area of a photometry unit on an imaging screen.

FIG. 4 is a diagram showing an arrangement of a color filter array of the image sensor.

FIG. 5 is a diagram showing a configuration of a basic block of a digital camera provided with the imaging device according to the present invention.

FIG. 6 is a flowchart showing a shooting procedure of a digital camera provided with the imaging device according to the present invention.

FIG. 7 is a flowchart illustrating a calculation procedure for calculating a correction gain for an exposure level.

FIG. 8 is a diagram showing regions corresponding to respective light receiving regions of nine light receiving elements in a captured image.

FIG. 9 is a diagram illustrating pixels included in a region corresponding to each light receiving region of a light receiving element in a captured image.

FIG. 10 is a diagram illustrating a basic block configuration of a digital camera including a conventional imaging device.

[Description of Signs] 1 Digital camera 2 Photographing lens 3 Photometry unit (brightness detection means) 4 Distance measurement unit 5 Flash 6 Viewfinder objective window 7 Card insertion slot 8 Card ejection button 9 Shutter button 10 CCD (photoelectric conversion means) 11 Memory card Reference Signs List 12 aperture (exposure control unit) 13 A / D converter 14 lens drive unit 15 aperture drive unit (exposure control unit, light amount control unit) 16 timing control unit (exposure control unit, exposure time control unit) 17 image processing unit 18 image Memory 19 Level correction unit (correction unit) 20 Control unit 201 Exposure control value calculation unit (first and second calculation units) 202 Exposure level calculation unit (third calculation unit) 203 Correction gain calculation unit (fourth calculation unit) means)

Continued on the front page F term (reference) 5C022 AA13 AB04 AB06 AB12 AB17 AB24 AB51 AC00 AC69 5C024 BA01 CA01 EA02 HA10 HA12 HA14

Claims (3)

[Claims] 1. A photoelectric conversion unit that photoelectrically converts a subject light image into an image signal and captures the image signal, a brightness detection unit that detects a subject brightness, and a first calculation unit that calculates an appropriate exposure level based on the subject brightness.
Calculating means for calculating the exposure control value of the photoelectric conversion means based on the appropriate exposure level; and exposing the photoelectric conversion means based on the exposure control value calculated by the second calculating means. Exposure control means for controlling the amount; third calculation means for calculating the exposure level of the image signal output from the photoelectric conversion means; and calculation of a correction amount for correcting an error between the proper exposure level and the exposure level. An image pickup apparatus comprising: a fourth calculating unit that performs an operation; and a correcting unit that corrects an exposure level of the image signal using the correction amount. 2. An imaging apparatus according to claim 1, wherein said exposure control means comprises an exposure time control means for controlling an exposure time of said photoelectric conversion means. 3. The image pickup apparatus according to claim 1, wherein the exposure control means includes a light quantity control means for controlling a light quantity incident on the photoelectric conversion means and an exposure time control means for controlling an exposure time of the photoelectric conversion means. An imaging device characterized by the above-mentioned.