H04N 25/616
Definition
Diese Klassifikationsstelle umfasst:(Für diese Definition ist die deutsche Übersetzung noch nicht abgeschlossen)
Details of circuits for implementing:
- double sampling (DS) – these circuits compensate for offsets caused by the varying characteristics of pixel amplifiers (source followers);
- correlated double sampling (CDS) – these circuits further reduce the kTC (reset) noise;
- multiple sampling – multiple sampling of a reset signal and an image signal from a pixel is used to reduce or average the random noise;
- (correlated) double/multiple sampling function implemented in the analogue domain, i.e. by using clamping circuits, or by using separate sampling capacitors for the reset signal and the image signal;
- (correlated) double sampling function implemented at least partially in the ADC;
- (correlated) double sampling function implemented in the digital domain;
- CDS circuits per pixel;
- details of arrangement of the CDS circuit as part of the readout circuit;
- CDS arranged per column;
- CDS arranged at the output of the sensor.
Beziehungen zu anderen Klassifikationsstellen
If the specific position of the CDS in the image sensor is to be classified, classification should be made under H04N 25/70 according to the respective SSIS architecture.
Correlated double sampling is a noise reduction technique in which the reference voltage of the pixel (i.e. the pixel's voltage after it is reset) is subtracted from the signal voltage of the pixel (i.e. the pixel's voltage at the end of integration) at the end of each integration period, to cancel kTC noise (the thermal noise associated with the sensor's capacitance). Therefore, classification should not be made in H04N 25/65 (reduction of kTC noise) if only CDS is used for kTC noise reduction.
H04N 25/616
Definition Statement
This place covers:Details of circuits for implementing:
- double sampling (DS) – these circuits compensate for offsets caused by the varying characteristics of pixel amplifiers (source followers);
- correlated double sampling (CDS) – these circuits further reduce the kTC (reset) noise;
- multiple sampling – multiple sampling of a reset signal and an image signal from a pixel is used to reduce or average the random noise;
- (correlated) double/multiple sampling function implemented in the analogue domain, i.e. by using clamping circuits, or by using separate sampling capacitors for the reset signal and the image signal;
- (correlated) double sampling function implemented at least partially in the ADC;
- (correlated) double sampling function implemented in the digital domain;
- CDS circuits per pixel;
- details of arrangement of the CDS circuit as part of the readout circuit;
- CDS arranged per column;
- CDS arranged at the output of the sensor.
Relationships with other classification places
If the specific position of the CDS in the image sensor is to be classified, classification should be made under H04N 25/70 according to the respective SSIS architecture.
Correlated double sampling is a noise reduction technique in which the reference voltage of the pixel (i.e. the pixel's voltage after it is reset) is subtracted from the signal voltage of the pixel (i.e. the pixel's voltage at the end of integration) at the end of each integration period, to cancel kTC noise (the thermal noise associated with the sensor's capacitance). Therefore, classification should not be made in H04N 25/65 (reduction of kTC noise) if only CDS is used for kTC noise reduction.