Solid-state imaging device, signal processing device and signal processing method for solid-state imaging device, and imaging apparatus

A solid-state imaging device comprising:

• a pixel array unit in which unit pixels including photoelectric conversion elements for converting light signals into signal charges are arranged in a matrix shape;
• and
• a signal processing circuit that obtains a first video signal imaged at first sensitivity and a second video signal imaged at second sensitivity and performs processing for combining the first and second video signals, wherein
• the signal processing circuit includes:
• judging means for comparing a level of a luminance value of the first video signal and a level of a luminance value of the second video signal of a pixel of interest in the pixel array unit with respect to a reference luminance value to thereby judge whether the pixel of interest is a pixel to be saturated during an exposure period;
• calculating means for setting the pixel of interest, which is judged by the judging means as the pixel to be saturated, as a correction pixel and calculating a correction amount on the basis of a luminance value of the second video signal of a peripheral pixel of the correction pixel;
• and
• correcting means for applying the correction amount calculated by the calculating means to a luminance value of the first video signal of the correction pixel to thereby correct a noise signal amount due to photo-charges leaking from the peripheral pixel into the correction pixel,
• wherein the calculating means subtracts the reference luminance value from a luminance value of the second video signal of the peripheral pixel and sets a value obtained by multiplying a result of the subtraction with a correction coefficient as the correction amount,
• wherein
• there are a plurality of the peripheral pixels, and
• the calculating means subtracts, for the respective plural peripheral pixels, the reference luminance value from luminance values of the second video signal of the peripheral pixels, calculates values obtained by multiplying results of the subtraction with a correction coefficient, and sets a sum of the values as the correction amount.

A solid-state imaging device comprising:

• a pixel array unit in which unit pixels including photoelectric conversion elements for converting light signals into signal charges are arranged in a matrix shape;
• and
• a signal processing circuit that obtains a first video signal imaged at first sensitivity and a second video signal imaged at second sensitivity and performs processing for combining the first and second video signals, wherein
• the signal processing circuit includes:
• judging means for comparing a level of a luminance value of the first video signal and a level of a luminance value of the second video signal of a pixel of interest in the pixel array unit with respect to a reference luminance value to thereby judge whether the pixel of interest is a pixel to be saturated during an exposure period;
• calculating means for setting the pixel of interest, which is judged by the judging means as the pixel to be saturated, as a correction pixel and calculating a correction amount on the basis of a luminance value of the second video signal of a peripheral pixel of the correction pixel;
• and
• correcting means for applying the correction amount calculated by the calculating means to a luminance value of the first video signal of the correction pixel to thereby correct a noise signal amount due to photo-charges leaking from the peripheral pixel into the correction pixel, wherein the signal processing circuit is provided in each unit column or each set of plural columns of a pixel array of the pixel array unit.

A signal processing method of obtaining a first video signal imaged at first sensitivity and a second video signal images at second sensitivity and performing processing for combining the first and second video signals in a solid-state imaging device including a pixel array unit in which unit pixels including photoelectric conversion elements for converting light signals into signal charges are arranged in a matrix shape, the signal processing method comprising the steps of:

• comparing a level of a luminance value of the first video signal and a level of a luminance value of the second video signal of a pixel of interest in the pixel array unit with respect to a reference luminance value to thereby judge whether the pixel of interest is a pixel to be saturated during an exposure period;
• setting the pixel of interest, which is judged in the judging step as the pixel to be saturated, as a correction pixel and calculating a correction amount on the basis of a luminance value of the second video signal of a peripheral pixel of the correction pixel;
• and
• applying the correction amount calculated in the calculating step to a luminance value of the first video signal of the correction pixel to thereby correct a noise signal amount due to photo-charges leaking from the peripheral pixel into the correction pixel,
• wherein, in the calculating step, the reference luminance value is subtracted from a luminance value of the second video signal of the peripheral pixel and a value obtained by multiplying a result of the subtraction with a correction coefficient is set as the correction amount, and wherein
• there is a plurality of the peripheral pixels, and
• in the calculating step, for the respective plural peripheral pixels, the reference luminance value is subtracted from luminance values of the second video signal of the peripheral pixels, values obtained by multiplying results of the subtraction with a correction coefficient are calculated, and a sum of the values is set as the correction amount.

An imaging apparatus comprising:

• a solid-state imaging device including a pixel array unit in which unit pixels including photoelectric conversion elements for converting light signals into signal charges are arranged in a matrix shape and a signal processing circuit that obtains a first video signal imaged at first sensitivity and a second video signal imaged at second sensitivity and performs processing for combining the first and second video signals;
• and
• an optical system that focuses incident light on an imaging surface of the solid-state imaging device, wherein
• the signal processing circuit includes:
• judging means for comparing a level of a luminance value of the first video signal and a level of a luminance value of the second video signal of a pixel of interest in the pixel array unit with respect to a reference luminance value to thereby judge whether the pixel of interest is a pixel to be saturated during an exposure period;
• calculating means for setting the pixel of interest, which is judged by the judging means as the pixel to be saturated, as a correction pixel and calculating a correction amount on the basis of a luminance value of the second video signal of a peripheral pixel of the correction pixel;
• and
• correcting means for applying the correction amount calculated by the calculating means to a luminance value of the first video signal of the correction pixel to thereby correct a noise signal amount due to photo-charges leaking from the peripheral pixel into the correction pixel.

A solid-state imaging device comprising:

• a pixel array unit in which unit pixels including photoelectric conversion elements for converting light signals into signal charges are arranged in a matrix shape;
• and
• a signal processing circuit that obtains a first video signal imaged at first sensitivity and a second video signal imaged at second sensitivity and performs processing for combining the first and second video signals, wherein
• the signal processing circuit includes:
• a judging unit comparing a level of a luminance value of the first video signal and a level of a luminance value of the second video signal of a pixel of interest in the pixel array unit with respect to a reference luminance value to thereby judge whether the pixel of interest is a pixel to be saturated during an exposure period;
• a calculating unit setting the pixel of interest, which is judged by the judging unit as the pixel to be saturated, as a correction pixel and calculating a correction amount on the basis of a luminance value of the second video signal of a peripheral pixel of the correction pixel;
• and
• a correcting unit applying the correction amount calculated by the calculating unit to a luminance value of the first video signal of the correction pixel to thereby correct a noise signal amount due to photo-charges leaking from the peripheral pixel into the correction pixel.