JP3212858B2 - Solid-state imaging device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a solid-state imaging device that forms image light and converts it into an electric signal.

[0002]

2. Description of the Related Art FIG. 5 is a block diagram showing the structure of a first conventional solid-state imaging device. In FIG. 5, 1 is a solid-state imaging device, 2 is a signal processing unit, 3 is an analog-digital conversion unit, and 4 is an imaging device control unit. In the solid-state imaging device in FIG. 5, the solid-state imaging device 1 accumulates electric charges according to the amount of light that has entered for each imaging period. The imaging device control means 4 controls the operation of the solid-state imaging device 1 so as to output a signal indicating the magnitude of the amount of charge accumulated in the solid-state imaging device 1 and reset the accumulated amount of charge to zero. The output signal from the solid-state imaging device 1 is subjected to processing such as noise removal, gamma correction, and amplification by the signal processing unit 2, and then input to the analog-digital conversion unit 3, where it is converted into a digital value and output.

FIG. 6 shows the relationship between the amount of charge accumulated during one imaging period of the solid-state imaging device 1 and the charge accumulation time, and shows the relationship between the amount of charge accumulated during one imaging period and the amount of incident light. FIG. 7 shows the relationship.

[0004]

In the configuration shown in FIG.
Due to the charge accumulation characteristics at the pixel positions of the solid-state imaging device 1, the captured image becomes an image of poor image quality including fixed pattern noise. The fixed pattern noise is a variation in the maximum storable charge amount of the solid-state imaging device 1 for each pixel, and the charge storage characteristic at a pixel position of the solid-state imaging device 1 changes according to the temperature of the solid-state imaging device 1 itself. A solid-state imaging device using a temperature measuring unit (temperature sensor) for removing noise has been proposed. This proposed example is shown in FIG. 8 as a second conventional solid-state imaging device.

FIG. 8 is a block diagram showing the configuration of a second conventional solid-state imaging device. 8, 1 is a solid-state imaging device, 2 is a signal processing unit, 3 is an analog-digital conversion unit, 4 is an imaging device control unit, 5 is an accumulated charge switching unit,
6 is a noise removing means, 7 is a comparing means, 8 is a storage means, 9
Denotes a temperature sensor, 10 denotes a storage unit, and 12 denotes an adding unit. 8, a solid-state imaging device 1, a signal processing unit 2, an analog-digital conversion unit 3, and an imaging device control unit 4 are the same as those of the first conventional example shown in FIG.

[0008] In the solid-state imaging device 1 shown in FIG. 8, the relationship between the amount of charge accumulated in one imaging period and the charge accumulation time is shown by a solid line A in FIG. 9, and the amount of charge accumulated in one imaging period The solid line B in FIG. Note that broken lines a and b in FIGS. 9 and 10 show characteristics of the first conventional solid-state imaging device shown in FIG. 5 for comparison, and are equivalent to FIGS. 6 and 7. .

The accumulated charge switching means 5 changes the potential (Vsub) applied to the solid-state image sensing device 1 for controlling the OFD (overflow drain) of the solid-state image sensing device 1 for a certain time within one image sensing period as shown in FIG. By changing with Tc, the amount of charge that can be accumulated in the solid-state imaging device 1 from the beginning within one imaging period to time Tc is the first charge Qsat1 (> 0), and after the time Tc, the second charge Qsat2. (> Qsat1) has a function of changing the output signal of the image sensor control means 4 and outputting it.

When the amount of charge that can be stored in the solid-state imaging device 1 is set to Qsat1, the storage unit 8 stores data obtained by performing analog-to-digital conversion on the amount of charge that is actually stored. The operation of the image sensor control unit 4 is controlled so that the pixel corresponding to the data output from the storage unit 3 and the pixel corresponding to the data output from the storage unit 8 are the same.

The temperature sensor 9 measures the temperature of the solid-state imaging device 1 or its surroundings, and the storage means 10 outputs a correction coefficient corresponding to the temperature data input from the temperature sensor 9 based on the conversion table held. I do. The correction coefficient output from the storage unit 10 and the data output from the storage unit 8 are added in the addition unit 12, and the addition result of the addition unit 12 is input to the comparison unit 7. The comparing means 7 has a function of comparing the magnitudes of the data input from the analog-digital converting means 3 and the adding means 12 and outputting the result.

If the output of the analog-to-digital converter 3 is smaller than the output of the adder 12 based on the comparison result input from the comparator 7, the noise removing unit 6 outputs the data input from the analog-digital converter 3. Is output as it is, and when the output of the analog-digital converter 3 is equal to or larger than the output of the adder 12, the input data from the analog-digital converter 3 is corrected and output based on the output data of the adder 12. .

In the solid-state imaging device shown in FIG.
When the charge amount that can be stored is set to the first charge amount Qsat1 and the charge amount that is actually stored changes according to the solid-state imaging device 1 or the ambient temperature of the solid-state imaging device 1, the charge amount is stored in the storage unit 8. The data stored in the storage unit 8 is corrected based on the temperature characteristics by the temperature sensor 9, the storage unit 10, and the addition unit 12 because the data stored in the data does not make sense as the reference value in the noise removal unit 6. I have.

As described above, in the second conventional example, since the charge accumulation characteristic at the pixel position of the solid-state image sensing device 1 changes depending on the temperature of the solid-state image sensing device 1 itself, the temperature sensor 9 measures the temperature of the solid-state image sensing device 1. Then, by correcting the data stored in the storage means 8 based on the temperature characteristics, the fixed pattern noise of the solid-state imaging device 1 is removed to prevent the image quality from deteriorating.

However, the temperature sensor 9 used in the second conventional example measures the temperature of the package surface of the solid-state imaging device 1, and the temperature of the package surface of the solid-state imaging device 1 depends on the ambient temperature. For example, even if the ambient temperature changes, the temperature of the solid-state imaging device 1 itself may be constant,
In some cases, the temperature of the solid-state imaging device 1 itself differs from the temperature measured by the temperature sensor 9. As described above, the temperature of the solid-state imaging device 1 cannot be accurately measured by the temperature sensor 9, and therefore, the temperature of the solid-state imaging device 1 is stored in the storage unit 8 using a measured temperature different from the temperature of the solid-state imaging device 1 itself. If the data is to be corrected, the fixed pattern noise cannot be satisfactorily removed, and good image quality cannot be obtained.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a solid-state imaging device capable of removing fixed pattern noise of a solid-state imaging device according to an accurate temperature of the solid-state imaging device itself and obtaining good image quality.

[0015]

According to a first aspect of the present invention, there is provided a solid-state imaging device comprising: a solid-state imaging device; storage means for storing data corresponding to the maximum storable charge amount of the solid-state imaging device; And a data correction amount setting unit that outputs a correction amount of data in the storage unit corresponding to the value of the dark current, and a data amount corresponding to the maximum storable charge amount using the data correction amount. Reference level setting means for correcting and outputting as a reference level, comparison means for outputting a control signal when the output signal level of the solid-state imaging device is equal to or higher than the reference level, and a control signal based on the reference level in response to the control signal of the comparison means. Noise removing means for correcting the output signal of the solid-state imaging device.

According to this configuration, the dark current is measured from the output of the solid-state imaging device by utilizing the fact that the logarithmic value of the dark current of the solid-state imaging device is proportional to the temperature, and the maximum accumulation is performed based on the measured value. By correcting the data corresponding to the possible charge, even when using a solid-state image sensor whose fixed pattern noise changes with temperature, the fixed pattern noise of the solid-state image sensor can be removed according to the accurate temperature of the solid-state image sensor itself. ,
An image without image quality deterioration due to fixed pattern noise can be obtained.

According to a second aspect of the present invention, there is provided a solid-state imaging device capable of controlling the amount of charge that can be stored, the first charge amount greater than zero, and the first charge amount being greater than zero. A storage charge switching unit that can be switched to a large second charge amount and switches in the order of the first charge amount and the second charge amount within one imaging period; and corresponds to the first charge amount of the solid-state imaging device. Storage means for holding data to be stored, dark current measurement means for measuring a dark current of the solid-state imaging device, data correction amount setting means for outputting a correction amount of data in the storage means corresponding to the value of the dark current, Reference level setting means for correcting data corresponding to the charge amount using the correction amount of data and outputting the corrected data as a reference level; andcomparing means for outputting a control signal when the output signal level of the solid-state imaging device is equal to or higher than the reference level. ,
Noise removing means for correcting the output signal of the solid-state imaging device based on the reference level in response to the control signal of the comparing means.

According to this configuration, as in the first aspect,
Even when using a solid-state image sensor whose fixed pattern noise changes with temperature, removing the fixed pattern noise of the solid-state image sensor according to the accurate temperature of the solid-state image sensor itself and obtaining an image without image quality deterioration due to the fixed pattern noise Can be. Further, the first charge amount, the second charge amount,
, The overflow drain control of the solid-state imaging device can be performed.

According to a third aspect of the present invention, there is provided a solid-state image pickup device.
In the solid-state imaging device described above, the amount of storable electric charge of the solid-state imaging device is replaced with the amount of storable electric charge of the solid-state imaging device instead of the storage electric charge switching means capable of switching the amount of storable electric charge of the solid-state imaging device between the first electric charge amount and the second electric charge amount. There is provided an accumulated charge switching means that can be switched between zero, a first charge amount, and a second charge amount, and that switches in the order of zero, the first charge amount, and the second charge amount within one imaging period. It is characterized by.

According to this configuration, in the configuration of claim 2, the stored charge switching means sets the storable charge amount of the solid-state image sensor to zero, the first charge amount, and the second charge amount within one imaging period. By performing the switching sequentially, the imaging time of the solid-state imaging device is shortened, and the same effect as when the shutter speed of the film camera is increased is obtained. it can.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the solid-state imaging device according to the first embodiment of the present invention. In FIG. 1, 1 is a solid-state imaging device, 2 is a signal processing unit, 3 is an analog-digital conversion unit, 4 is an imaging device control unit, 6 is a noise removal unit, 7 is a comparison unit, 8 is a storage unit, and 10 is a storage unit. Means (data correction amount setting means), 11
Denotes subtraction means (dark current measurement means), 12 denotes addition means (reference level setting means), 13 denotes delay means (dark current measurement means)
It is. In addition, the solid-state imaging device 1, the signal processing unit 2, the analog-digital conversion unit 3, the imaging device control unit 4, the noise removal unit 6, the comparison unit 7, the storage unit 8, and the storage unit 10.
The addition means 12 is the same as that shown in FIG.

FIG. 2 shows the effective pixel section of the pixel.
FIG. 7 is a diagram illustrating an output waveform of the analog-digital conversion unit 3 in a state where incident light is shielded . In FIG. 2, indicates one horizontal period, indicates the output period of the effective pixel unit, and indicates the output period of the idle feeding unit . FIG. 3 is a schematic configuration diagram of the solid-state imaging device 1, in which 21 is a photodiode, and 22 is a VC.
CD (vertical CCD), 23 is HCCD (horizontal C)
CD) and 24 are output amplifiers.

First, the points in the embodiment of the present invention will be described with reference to FIGS. FIG.
The output of the effective pixel portion during the period includes noise components generated by the photodiode 21, the VCCD 22, the HCCD 23, and the output amplifier 24 of FIG. 3, and the output of the idle feeding portion during the period of FIG. It includes noise components generated by the VCCD 22, HCCD 23 and output amplifier 24 in FIG. Therefore, the difference between the outputs in the period shown in FIG. 2, that is, the difference between the output of the effective pixel unit and the output of the idle feeding unit indicates the noise component in the photodiode 21, that is, the magnitude of the dark current of the photodiode 21. .

In this embodiment, the photodiode 2
Using the fact that the logarithmic value of the dark current of 1 is proportional to temperature,
The dark current is measured from the output of the solid-state imaging device (the output of the analog-to-digital converter 3 in FIG. 1), and the coefficient for removing the fixed pattern noise is corrected based on the measured value to obtain a solid-state image. It is intended to obtain an image of good image quality which is not affected by the temperature of the element and its surroundings.

Further, the first embodiment will be described with reference to FIG. The storage unit 8 stores the charge amount corresponding to the fixed pattern noise of the solid-state imaging device 1 in analog form.
Digitally converted data, that is, data corresponding to the maximum storable charge amount of the solid-state imaging device 1 is stored,
The image sensor control means 4 is controlled so that the pixels corresponding to the data output from the analog-digital conversion means 3 and the pixels corresponding to the data output from the storage means 8 are the same.
The operation is controlled by

The subtraction means 11 receives the output of the analog-digital conversion means 3 and the output of the delay means 13 and
, The difference between the output of the effective pixel section during the period and the output of the idle feed section during the period, that is, the dark current, is calculated, and the result is output. The storage unit 10 outputs a correction coefficient corresponding to the value output by the subtraction unit 11 based on the held conversion table. This storage means 10 stores the image sensor control means 4
The operation is controlled in the same manner as the storage means 8. The correction coefficient output from the storage unit 10 and the data output from the storage unit 8 are added in the addition unit 12, and the addition result of the addition unit 12 is input to the comparison unit 7.

The comparing means 7 compares the size of the data inputted from the analog-digital converting means 3 and the data inputted from the adding means 12 and outputs the result to the noise removing means 6. When the output of the analog-to-digital converter 3 is smaller than the output of the adder 12, based on the comparison result input from the comparator 7, the noise removing unit 6 outputs the data input from the analog-digital converter 3 as it is. If the output of the analog-to-digital converter 3 is equal to or higher than the output (reference level) of the adder 12, the input data from the analog-to-digital converter 3 is corrected and output based on the output data of the adder 12. I do. That is, data obtained by subtracting the fixed pattern noise component is output.

In FIG. 1, when data corresponding to the fixed pattern noise of the solid-state imaging device 1 is stored in the storage unit 8, the data stored in the storage unit 8 is noise-free due to a temperature change of the solid-state imaging device 1. Since the meaning as the reference value in the removing means 6 is not used, the storage means 1
The data stored in the storage unit 8 is corrected by 0, the subtraction unit 11, the addition unit 12, and the delay unit 13 based on the temperature characteristics.

As described above, according to the first embodiment, even if the solid-state imaging device 1 in which the fixed pattern noise changes depending on the temperature is used, the fixed pattern noise is changed in accordance with the accurate temperature of the solid-state imaging device 1 itself. Can be removed, and an image without image quality degradation due to fixed pattern noise can be obtained. Next, a second embodiment of the present invention will be described.

FIG. 4 is a block diagram showing a configuration of a solid-state imaging device according to a second embodiment of the present invention. In FIG. 4, 1 is a solid-state imaging device, 2 is a signal processing unit, 3 is an analog-digital conversion unit, 4 is an imaging device control unit, 5 is an accumulated charge switching unit, 6 is a noise removal unit, 7 is a comparison unit,
8 is a storage unit, 10 is a storage unit (data correction amount setting unit), 11 is a subtraction unit (dark current measurement unit), 12 is an addition unit (reference level setting unit), and 13 is a delay unit (dark current measurement unit). is there. In FIG. 4, a solid-state imaging device 1, a signal processing unit 2, an analog-digital conversion unit 3,
Image sensor control means 4, noise removing means 6, comparing means 7,
Storage means 8, storage means 10, subtraction means 11, addition means 1
2 and the delay means 13 are the same as those shown in the first embodiment of FIG.

The stored charge switching means 5 is the same as that shown in the second conventional example (FIG. 8),
For the purpose of (overflow drain) control, the potential (Vsub) applied to the solid-state imaging device 1 is changed at a certain time Tc within one imaging period (see FIG. 9), so that the potential from the beginning within one imaging period to time Tc is changed. The charge amount that can be stored in the solid-state imaging device 1 is the first charge amount Qsat1 (> 0), and the time Tc
After that, it has a function of changing the output signal of the image sensor control means 4 and outputting it so as to switch to the second charge amount Qsat2 (> Qsat1).

When the storable charge amount of the solid-state imaging device 1 is set to the first charge amount Qsat1, the storage means 8 stores analog-to-digital converted data of the charge amount actually stored. The pixel corresponding to the data output from the analog-digital conversion means 3 and the pixel corresponding to the data output from the storage means 8 are the same,
The operation is controlled by the image sensor control means 4.

The subtraction means 11 receives the output of the analog-digital conversion means 3 and the output of the delay means 13 and obtains the difference between the output of the effective pixel section in FIG. Is calculated and the result is output. The storage unit 10 outputs a correction coefficient corresponding to the value output by the subtraction unit 11 based on the held conversion table. The operation of the storage unit 10 is controlled by the image sensor control unit 4 in the same manner as the storage unit 8. Storage means 1
The correction coefficient output from 0 and the data output from the storage unit 8 are added in the addition unit 12, and the addition result of the addition unit 12 is input to the comparison unit 7.

The comparing means 7 compares the size of the data inputted from the analog-digital converting means 3 and the data inputted from the adding means 12, and outputs the result to the noise removing means 6. When the output of the analog-to-digital converter 3 is smaller than the output of the adder 12, based on the comparison result input from the comparator 7, the noise removing unit 6 outputs the data input from the analog-digital converter 3 as it is. If the output of the analog-to-digital converter 3 is equal to or higher than the output (reference level) of the adder 12, the input data from the analog-to-digital converter 3 is corrected and output based on the output data of the adder 12. I do.

In the solid-state imaging device shown in FIG. 4, when the storable charge amount of the solid-state imaging device 1 is set to the first charge amount Qsat1, the actually stored charge amount is not exactly Qsat1, There is an error (difference between the actually accumulated charge amount and Qsat1). The same occurs in the solid-state imaging device 1 of the first embodiment (the solid-state imaging device in FIG. 1).
In the second embodiment, this error is detected for each pixel by the comparison means 7, the storage means 8, and the image sensor control means 4, and furthermore, the error is detected by a change in the temperature of the solid-state image sensor 1 or its surrounding temperature. Storage means 10, subtraction means 11, delay means 1
3, the error can be removed and added to or subtracted by the noise removing means 6 in accordance with the magnitude of the error, thereby removing the error and aligning it with Qsat1.

As described above, according to the second embodiment, even if the solid-state imaging device 1 in which the fixed pattern noise changes according to the temperature is used, the fixed pattern noise is changed according to the accurate temperature of the solid-state imaging device 1 itself. And the dynamic range can be improved without deteriorating the image quality. The stored charge switching means 5 changes the amount of charge that can be stored in the solid-state imaging device 1 into a first charge amount Qsat1 and a second charge amount Qsat1.
In addition to sat2, the solid-state imaging device 1 can be switched to zero, and is switched in the order of zero, the first charge amount Qsat1, and the second charge amount Qsat2 in one imaging period.
In this case, the same effect as when the shutter speed of the film camera is increased can be obtained, and an image with less "blur" can be obtained with respect to the imaging of a moving object.

As described above, in the first and second embodiments, the temperature sensor 9 as shown in FIG. 8 is not used, so that the solid-state image sensor 1 is not affected by the ambient temperature of the solid-state image sensor 1. Good image quality with fixed pattern noise removed can be obtained according to the exact temperature of itself. It should be noted that the present invention is not limited to the above embodiment, and various modifications can be made based on the gist of the present invention, and these are not excluded from the scope of the present invention.

[0038]

According to a first aspect of the present invention, there is provided a solid-state imaging device, a solid-state imaging device, storage means for storing data corresponding to the maximum storable charge amount of the solid-state imaging device, and a dark circuit for measuring a dark current of the solid-state imaging device. A current measuring means, a data correction amount setting means for outputting a correction amount of data in the storage means corresponding to the value of the dark current, and a reference level for correcting data corresponding to the maximum storable charge amount using the correction amount of data. Reference level setting means for outputting as a reference signal, a comparison means for outputting a control signal when the output signal level of the solid-state image sensor is equal to or higher than the reference level, and a solid-state image sensor based on the reference level in response to the control signal of the comparison means. Noise removing means for correcting the output signal, utilizing the fact that the logarithmic value of the dark current of the solid-state image sensor is proportional to the temperature, measuring the dark current from the output of the solid-state image sensor, and measuring the dark current. By correcting the data corresponding to the maximum storable charge amount based on the value, even by using a solid-state imaging device that changes the fixed pattern noise by temperature,
The fixed pattern noise can be removed in accordance with the accurate temperature of the solid-state imaging device itself, and an image without image quality degradation due to the fixed pattern noise can be obtained.

According to a second aspect of the present invention, there is provided a solid-state imaging device capable of controlling the amount of storable charge, the first charge amount larger than zero and the first charge amount being larger than zero. A storage charge switching unit that can be switched to a large second charge amount and switches in the order of the first charge amount and the second charge amount within one imaging period; and corresponds to the first charge amount of the solid-state imaging device. Storage means for holding data to be stored, dark current measurement means for measuring a dark current of the solid-state imaging device, data correction amount setting means for outputting a correction amount of data in the storage means corresponding to the value of the dark current, Reference level setting means for correcting data corresponding to the charge amount using the correction amount of data and outputting the corrected data as a reference level; andcomparing means for outputting a control signal when the output signal level of the solid-state imaging device is equal to or higher than the reference level. ,
2. A solid-state imaging device according to claim 1, further comprising a noise removing unit that corrects an output signal of the solid-state imaging device based on a reference level in response to a control signal of the comparing unit. Is used, fixed pattern noise can be removed in accordance with the accurate temperature of the solid-state imaging device itself, and an image without image quality degradation due to fixed pattern noise can be obtained. Furthermore, the overflow drain control of the solid-state imaging device can be performed by providing the accumulated charge switching means for switching in the order of the first charge amount and the second charge amount within one imaging period.

According to a third aspect of the present invention, there is provided a solid-state imaging device according to the second aspect.
In the solid-state imaging device described above, the stored charge switching means sets the storable charge amount of the solid-state imaging device to zero, the first charge amount, and the second charge amount.
The charge time can be switched to zero, the first charge amount, and the second charge amount in one imaging period, so that the imaging time of the solid-state imaging device is shortened, and the film camera The same effect as in the case where the shutter speed is increased can be obtained, and an image with less "blur" can be obtained with respect to imaging of a moving object.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a solid-state imaging device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an output waveform of an analog-digital conversion unit according to the embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a solid-state imaging device according to an embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a solid-state imaging device according to a second embodiment of the present invention.

FIG. 5 is a block diagram showing the configuration of a first conventional solid-state imaging device.

FIG. 6 is a characteristic diagram showing the relationship between the amount of charge accumulated during one imaging period of a CCD of the first conventional solid-state imaging device and the charge accumulation time.

FIG. 7 is a diagram showing the relationship between the amount of charge accumulated during one imaging period of a CCD and the amount of incident light in the solid-state imaging device of the first conventional example.

FIG. 8 is a block diagram illustrating a configuration of a second conventional solid-state imaging device.

FIG. 9 is a characteristic diagram showing a relationship between the amount of charge accumulated in one imaging period of a CCD of the second conventional solid-state imaging device and the charge accumulation time.

FIG. 10 is a diagram showing the relationship between the amount of charge accumulated during one imaging period of a CCD of the second conventional solid-state imaging device and the amount of incident light.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solid-state image sensor 2 Signal processing means 3 Analog-digital conversion means 4 Image sensor control means 5 Accumulated charge switching means 6 Noise removal means 7 Comparison means 8 Storage means 9 Temperature sensor 10 Storage means (data correction amount setting means) 11 Subtraction means (Dark current measuring means) 12 adding means (reference level setting means) 13 delaying means (dark current measuring means)

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 5/335

Claims (3)

(57) [Claims] 1. A solid-state image sensor, storage means for holding data corresponding to the maximum storable charge amount of the solid-state image sensor, dark current measuring means for measuring a dark current of the solid-state image sensor, and the dark current A data correction amount setting unit that outputs a correction amount of the data in the storage unit corresponding to the value of (a); Level setting means, comparing means for outputting a control signal when the output signal level of the solid-state imaging device is equal to or higher than the reference level, and the solid-state imaging device based on the reference level in response to the control signal of the comparing means A solid-state imaging device comprising: a noise removing unit that corrects an output signal of an element. 2. A solid-state imaging device capable of controlling the amount of storable electric charge, and a first solid-state imaging device having a storable amount of electric charge larger than zero.
And a second charge amount larger than the first charge amount, and the stored charge switching means switches in the order of the first charge amount and the second charge amount within one imaging period Storage means for holding data corresponding to the first charge amount of the solid-state imaging device; dark current measurement means for measuring dark current of the solid-state imaging device; and storage corresponding to the value of the dark current. Data correction amount setting means for outputting a correction amount of data of the means, reference level setting means for correcting data corresponding to the first charge amount using the correction amount of the data, and outputting the corrected data as a reference level; Comparing means for outputting a control signal when the output signal level of the image sensor is equal to or higher than the reference level; and correcting the output signal of the solid-state image sensor based on the reference level in response to the control signal of the comparing means. The solid-state imaging device that includes a noise removing unit. 3. A method according to claim 1, wherein said storage means comprises a charge storage means for switching a charge amount of said solid-state image pickup device between a first charge amount and a second charge amount. A storage charge switching unit is provided which is switchable between the first charge amount and the second charge amount and switches in the order of zero, the first charge amount, and the second charge amount within one imaging period. The solid-state imaging device according to claim 2, wherein: