ams’ TMF8801 is the world’s smallest integrated module for direct time-of-flight (ToF) distance measurement providing accurate measurements from 2cm up to 2.5m. Measuring in at more than 30% smaller than competing ToF sensors, the sensor system is ideal for compact space constrained designs and offers superior performance in important parameters including accuracy and usability in the presence of sunlight.
The TMF8801 improves world-facing mobile phone camera performance using laser detection auto-focus (LDAF), enabling mobile phone users to take pin-sharp photos and selfies. When used to support this function, high accuracy distance measurements deliver improved camera performance: sharper, in-focused images under any ambient lighting conditions, and accurate adjustment of the camera flash brightness to improve picture quality.
Competing ToF sensors struggle to accurately measure distance below dirty or smudged cover glass whereas the TMF8801 maintains high accuracy through use of its on-chip histogram processing. The histogram is used to detect cover glass and report object distances operating with the highest SNR while compensating for dirt and smudge contaminants on the cover glass, producing artifact free measurement. The histogram delivers dynamic cover glass calibration and crosstalk compensation and background light noise is minimized through on-chip sunlight rejection filters.
The ams TMF8801 is a true direct time-of-flight (ToF) sensor system that enables laser detection auto-focus so a smartphone camera can zero in on a target with accurate distance measurement — even when the cover glass is smudged or dirty. In a single modular package, the TMF8801 offers precise depth accuracy detection through a sub-nanosecond light pulse and an antialiasing “stop-watch” method to measure round-trip time of pulse. It provides single zone detection of an object irrespective of the color, reflectivity and texture of the object.
With an integrated VCSEL infrared emitter, multiple SPAD (single photon avalanche photo-diode) light detectors, time-to-digital converter, and on-chip microcontroller for processing histograms, the TMF8801 delivers superior ToF performance. Compared to distance averaging employed with an indirect ToF system, the direct ToF time measurement methodology used in the TMF8801 delivers higher accuracy true-distance measurements. The single module with VCSEL emitter offers high dynamic range and detection sensing measurements from 2 cm to 250 cm distances. The device utilizes highly sensitive SPAD detection with fast compact time-to-digital converters to make highly accurate distance measurements within ±5% and is can operate in both dark and bright environments. Data output is through a 1.8V I²C fast-mode communications interface and an integrated micro controller is featured with all algorithms included on-chip with no need for external optics.