Time of flight imaging using long and short-exposure storage nodes

A method of operating a time-of-flight camera, the method comprising:

• integrating a plurality of pixels via a global shutter during an integration period comprising a short-exposure interval and a long-exposure interval, each pixel of the plurality of pixels comprising one or more taps;
• for each tap,
• directing charge generated during the short-exposure interval to a short-exposure storage node via a short-exposure switch gate, and
• directing charge generated during the long-exposure interval to a long-exposure storage node via a long-exposure switch gate;
• and
• during a readout period,
• reading out charge stored on the short-exposure storage node and charge stored on the long-exposure storage node via one or more floating diffusion (FD) capacitors.

A time-of-flight camera, comprising:

• a global shutter image sensor comprising a plurality of pixels, each pixel of the plurality of pixels comprising
• one or more taps, each tap comprising
• a photogate,
• a short-exposure storage node configured to receive charge during a short-exposure interval of an integration period,
• a long-exposure storage node configured to receive charge during a long-exposure interval of the integration period,
• a short-exposure switch gate configured to direct charge generated during the short-exposure interval to the short-exposure storage node,
• a long-exposure switch gate configured to direct charge generated during the long-exposure interval to the long-exposure storage node,
• a readout mechanism comprising one or more floating diffusion (FD) capacitors, and instructions executable to
• determine a long-exposure signal and a short-exposure signal,
• if the long-exposure signal is not saturated, read out the long-exposure signal as a pixel signal, and
• if the long-exposure signal is saturated, read out the short-exposure signal multiplied by a ratio of the long-exposure interval to the short-exposure interval as the pixel signal.