US 12747981 B2 / Sep 29, 2026

Laser detection using multiple image sensors

A silicon-based image sensor has an upconversion layer of crystals. The silicon-based image sensor receives light from a common beam splitter with a second image sensor. An optical band pass filter cooperates with the common beam splitter to pass some of the light to be incident on the upconversion layer of crystals in a second range of wavelengths, which will be absorbed and converted by the upconversion layer of crystals into a third range of wavelengths, and then the third range of wavelengths is transmitted onto the pixels in the silicon-based image sensor. A pulse repetition frequency decoder cooperates with the upconversion layer of crystals to decode a pulse repetition frequency of a laser flash in the second range of wavelengths passed by the optical band pass filter and subsequently upconverted by the upconversion layer of crystals and then captured by the pixels of the silicon-based image sensor.