Image sensor apparatus and method for obtaining multiple exposures with zero interframe time

An apparatus, comprising:

• image sensor means for capturing a plurality of frames;
• at least one circuit means for generating a first amplified analog signal based on application of a first gain to at least one analog signal from at least one of the plurality of frames, and for generating a second amplified analog signal based on application of a second gain to the at least one analog signal from the plurality of frames, such that the second gain differs from the first gain;
• a first analog-to-digital converter means for converting the first amplified analog signal to a first digital signal;
• a second analog-to-digital converter means for converting the second amplified analog signal to a second digital signal;
• and
• means for generating a high dynamic range (HDR) image based on the first digital signal and the second digital signal.

An apparatus, comprising:

• an image sensor including a plurality of cells each corresponding with a pixel and each including a first photodiode and a second photodiode both positioned behind a filter for a single color;
• and
• a plurality of circuits each including:
• a first amplifier in communication with the image sensor, the first amplifier amplifying a first signal generated by one of the cells based on a first gain and, subsequently, amplifying the first signal based on a second gain that is greater than the first gain,
• a second amplifier in communication with the image sensor, the second amplifier amplifying a second signal generated by the one of the cells based on the first gain and, subsequently, amplifying the second signal based on the second gain that is greater than the first gain,
• a first analog-to-digital converter in communication with the first amplifier, the first analog-to-digital converter converting an output of the first amplifier from an analog format to a digital format, and
• a second analog-to-digital converter in communication with the second amplifier, the second analog-to-digital converter converting an output of the second amplifier from the analog format to the digital format, such that a high dynamic range (HDR) image is generated based, at least in part, on an output of the first analog-to-digital converter and an output of the second analog-to-digital converter.

A method, comprising:

• at one of a plurality of circuits for one of a plurality of cells of an image sensor, where each of the plurality of circuits includes a first amplifier, a second amplifier, a first analog-to-digital converter, and a second analog-to-digital converter, and each of the plurality of cells corresponds with a pixel and includes a first photodiode and a second photodiode both receiving light via a single filter:
• identifying a first gain for the first amplifier and the second amplifier;
• amplifying, utilizing the first amplifier and based on the first gain, a first signal generated by the one of the cells;
• amplifying, utilizing the second amplifier and based on the first gain, a second signal generated by the one of the cells;
• converting, utilizing the first analog-to-digital converter, the first signal amplified based on the first gain from an analog format to a digital format;
• converting, utilizing the second analog-to-digital converter, the second signal amplified based on the first gain from the analog format to the digital format;
• identifying a second gain, that is greater than the first gain, for the first amplifier and the second amplifier;
• amplifying, utilizing the first amplifier and based on the second gain, the first signal generated by the one of the cells;
• amplifying, utilizing the second amplifier and based on the second gain, the second signal generated by the one of the cells;
• converting, utilizing the first analog-to-digital converter, the first signal amplified based on the second gain from the analog format to the digital format;
• converting, utilizing the second analog-to-digital converter, the second signal amplified based on the second gain from the analog format to the digital format;
• and
• outputting the converted first signal amplified based on the first gain, the converted second signal amplified based on the first gain, the converted first signal amplified based on the second gain, and the converted second signal amplified based on the second gain, for generation of at least a portion of at least one high dynamic range (HDR) image.

An apparatus, comprising:

• an image sensor including a plurality of lines of cells with each cell corresponding with a pixel and with each cell including a first photodiode and a second photodiode both receiving light via a filter for a single color, the first photodiode generating a first analog signal corresponding to a portion of one frame of a plurality of frames captured by the first photodiode of the image sensor, the second photodiode generating a second analog signal corresponding to a portion of the one frame of the plurality of frames captured by the second photodiode of the image sensor;
• and
• a plurality of circuits in communication with the image sensor, the plurality of circuits together processing the plurality of lines of cells for the one frame, one line at a time, each of the plurality of circuits including, for use with a corresponding cell of each of the plurality of lines:
• a first variable amplifier in communication with the image sensor, the first variable amplifier, for the corresponding cell of each of the plurality of lines for the one frame, sequentially generating a first-amplifier/first-gain analog signal based on application of a first gain to the first analog signal until the first-amplifier/first-gain analog signal is generated for the corresponding cell of each of the plurality of lines for the one frame, after which a first-amplifier/second-gain analog signal is sequentially generated by the first variable amplifier based on application of a second gain greater than the first gain to the first analog signal until the first-amplifier/second-gain analog signal is generated for the corresponding cell of each of the plurality of lines for the one frame,
• a second variable amplifier in communication with the image sensor, the second variable amplifier, for the corresponding cell of each of the plurality of lines for the one frame, sequentially generating a second-amplifier/first-gain analog signal based on application of the first gain to the second analog signal until the second-amplifier/first-gain analog signal is generated for the corresponding cell of each of the plurality of lines for the one frame, after which a second-amplifier/second-gain analog signal is sequentially generated by the second variable amplifier based on application of the second gain to the second analog signal until the second-amplifier/second-gain analog signal is generated for the corresponding cell of each of the plurality of lines for the one frame,
• a first analog-to-digital converter in communication with the first variable amplifier, the first analog-to-digital converter, for the corresponding cell of each of the plurality of lines for the one frame, sequentially converting the first-amplifier/first-gain analog signal to a first-amplifier/first-gain digital signal until the first-amplifier/first-gain digital signal is generated for the corresponding cell of each of the plurality of lines for the one frame, after which the first-amplifier/second-gain analog signal is sequentially converted by the first analog-to-digital converter to a first-amplifier/second-gain digital signal until the first-amplifier/second-gain digital signal is generated for the corresponding cell of each of the plurality of lines for the one frame, and
• a second analog-to-digital converter in communication with the second variable amplifier, the second analog-to-digital converter, for the corresponding cell of each of the plurality of lines for the one frame, sequentially converting the second-amplifier/first-gain analog signal to a second-amplifier/first-gain digital signal until the second-amplifier/first-gain digital signal is generated for the corresponding cell of each of the plurality of lines for the one frame, after which the second-amplifier/second-gain analog signal is sequentially converted by the second analog-to-digital converter to a second-amplifier/second-gain digital signal until the second-amplifier/second-gain digital signal is generated for the corresponding cell of each of the plurality of lines for the one frame;
• wherein the apparatus is configured such that a high dynamic range (HDR) image is generated, for the one frame, by:
• generating a first-amplifier/first-gain frame-level digital signal based on each first-amplifier/first-gain digital signal that is generated for the corresponding cell of each of the plurality of lines for the one frame,
• generating a first-amplifier/second-gain frame-level digital signal based on each first-amplifier/second-gain digital signal that is generated for the corresponding cell of each of the plurality of lines for the one frame,
• generating a second-amplifier/first-gain frame-level digital signal based on each second-amplifier/first-gain digital signal that is generated for the corresponding cell of each of the plurality of lines for the one frame,
• generating a second-amplifier/second-gain frame-level digital signal based on each second-amplifier/second-gain digital signal that is generated for the corresponding cell of each of the plurality of lines for the one frame, and
• combining at least two of:
• the first-amplifier/first-gain frame-level digital signal, the first-amplifier/second-gain frame-level digital signal, the second-amplifier/first-gain frame-level digital signal, and the second-amplifier/second-gain frame-level digital signal, to generate a combined frame-level digital signal, which is combined with another combined frame-level digital signal.

An apparatus, comprising:

• an image sensor including a plurality of lines of cells with each cell including a first photodiode and a second photodiode both positioned behind a filter for a single color;
• a plurality of circuits each in communication with a corresponding cell of each of the plurality of lines of cells of the image sensor, each of the plurality of circuits including a first variable amplifier, a second variable amplifier, a first analog-to-digital converter, and a second analog-to-digital converter;
• and
• circuitry in communication with the plurality of circuits, wherein the circuitry, when executed, causes the apparatus to:
• process the plurality of lines of cells of the image sensor, one line at a time, such that each of the plurality of circuits is caused to:
• output, in sequence for the corresponding cell of each of the plurality of lines for one frame, two first-gain cell-level digital signals converted from two amplified first-gain cell-level analog signals generated based on application of a first gain to two cell-level analog signals generated by the corresponding cell, until the two first-gain cell-level digital signals are output for the corresponding cell of each of the plurality of lines for the one frame, after which there is output of two second-gain cell-level digital signals converted from two amplified second-gain cell-level analog signals generated based on application of a second gain, that is greater than the first gain, to the two cell-level analog signals, until the two second-gain cell-level digital signals are output for the corresponding cell of each of the plurality of lines for the one frame,
• generate, for the one frame, two first-gain frame-level digital signals based on the two first-gain cell-level digital signals that are output for the corresponding cell of each of the plurality of lines for the one frame, and two second-gain frame-level digital signals based on the two second-gain cell-level digital signals that are output for the corresponding cell of each of the plurality of lines for the one frame, and
• generate, for the one frame, a high dynamic range (HDR) image, based on at least one of:
• at least one of the two first-gain frame-level digital signals, or at least one of the two second-gain frame-level digital signals.