Absolute distance measurement for time-of-flight sensors

A time-of-flight (TOF) sensor device, comprising:

• an illumination component configured to emit a light beam toward a viewing space;
• a receiving lens element configured to receive reflected light and to direct the reflected light to a photo-receiver array;
• a processor configured to:
• generate distance information for a pixel corresponding to an object in the viewing space based on time-of-flight analysis of the reflected light;
• record a variation of an intensity of the reflected light from the object over time to yield intensity variation information;
• record a variation of the distance information for the pixel corresponding to the object over time to yield distance variation information;
• and
• apply a correction factor to the distance information in response to a determination that the intensity variation information and the distance variation information do not conform to an inverse-square relationship, wherein the correction factor is determined based at least in part on a deviation from the inverse-square relationship between the intensity variation information and the distance variation information.

A time-of-flight (TOF) sensor device, comprising:

• an illumination component configured to emit a light beam toward a viewing space;
• a receiving lens element configured to receive reflected light and to direct the reflected light to a photo-receiver array;
• a processor configured to:
• generate distance information for a pixel corresponding to an object in the viewing space based on time-of-flight analysis of the reflected light;
• record a variation of an intensity of the reflected light from the object over time to yield intensity variation information;
• record a variation of the distance information for the pixel corresponding to the object over time to yield distance variation information;
• and
• apply a correction factor to the distance information in response to a determination that the intensity variation information and the distance variation information do not conform to an inverse-square relationship, wherein the processor is configured to sample distance information for the pixel corresponding to the object at a predetermined sampling rate, and wherein the processor is configured to tabulate the sampled distance information over time to yield a representation of the distance variation information.