The TOF imager is the heart of the TOF camera. The key issue is the sensitivity in the wavelength domain being used. The higher the sensitivity, the lower the required illumination power. And thus, the longer the operating range without violating the eye safety requirements. ESPROS TOF imagers provide the highest sensitivity in their field due to the unmatched quantum efficiency (QE) in the near infrared wavelength domain.
Another aspect is ambient light suppression. The photons of the modulated light compete with the photons from the sun. It’s a massive competition. Typically few photons from the illumination are reflected from the object, but large amounts of photons from the sun are arriving on the imager. The separation between the two sources is challenging. One part can be done by wavelength filtering. But even then, distance measurement is not possible with a powerful ambient light suppression technology. ESPROS TOF imagers have a built in Ambient light suppression (ABS). Due to the unique CCD/CMOS technology, ambient light is subtracted in the charge domain from the modulated signal. The full well capacity of the ESPROS TOF imagers is up to 10 Million electrons, whereas the sensitivity starts at several hundred electrons. The result is an outstanding outdoor performance.