SPAD ToF Sensor Background Light Elimination

The patent extracts and processes only the critical timing information (time-of-flight data) while discarding redundant background light data. By focusing solely on timing measurements rather than storing and processing complete light intensity data, the system achieves background light elimination without requiring large memory capacity or complex data processing algorithms.

The patent replaces complex software-based data processing and large memory storage with a streamlined hardware-based timing measurement approach. By using dedicated timing circuitry to directly measure photon arrival times and calculate distances, the system eliminates the need for complex computational algorithms and large memory buffers, thereby reducing device complexity while maintaining background light rejection capability.

The patent performs preliminary timing measurement on all detected photons, but only retains and processes those with timing values within the expected range for actual target reflections. By pre-measuring and then filtering based on timing criteria, the system maintains complete photon detection while ensuring measurement precision through selective processing of valid photons.

The patent converts the harmful effect of background light photons into a beneficial filtering mechanism. By measuring the timing of all photons including background light, the system can identify and exclude background photons based on their unrealistic timing values (either too early or too late), thereby using the complete detection data to improve measurement precision through statistical filtering of valid versus invalid photons.