STMicroelectronics' VL53L1X time-of-flight sensor has a range from 4 cm to 4 meters (in dark ambient conditions) using infrared light to directly measure the distance to a reflective object. The transit time is measured for the outward and return journey of the emitted photons. The distance measurement with such optical time-of-flight sensors is reliable and largely independent of the reflectivity, surface properties and color of the target.

Measuring just 4.9 x 2.5 x 1.56 mm the fully integrated ToF sensor module VL53L1X is very compact and pin-compatible with its predecessor, the VL53L0X module. Contained within the module package is the laser driver stage, the laser diode itself and the light receiver which takes the form of a single-photon avalanche diode detection array. The sensor operates using infrared light at 940 nm wavelength which makes it insensitive to visible light emissions and allows covert operation using various types of window materials. In addition to its range of up to 4 m, the sensor achieves a maximum measurement rate of 50 Hz and has a 27 ° field of view (FOV). The sensor uses a 2.8 V supply and has a fast I²C interface allowing a 400 kbits/s data rate.