Terahertz enhanced foreign object debris discrimination for optical particulate sensor

A system for particulate discrimination, comprising:

• a controller;
• a particulate sensor comprising a first set of sensing elements, and a second set of sensing elements;
• a tangible, non-transitory memory configured to communicate with the controller, the tangible, non-transitory memory having instructions stored thereon that, in response to execution by the controller, perform operations comprising:
• emitting a first electromagnetic radiation pulse within a first wavelength range from a first electromagnetic radiation source into a sensing volume;
• emitting a second electromagnetic radiation pulse within a second wavelength range from a second electromagnetic radiation source into the sensing volume, wherein the second wavelength range is within the terahertz (THz) regime;
• receiving a scattered light from each of the first and the second electromagnetic radiation sources at a plurality of sensing devices as a first and second electromagnetic radiation return;
• comparing, using the controller, the first electromagnetic radiation returns and the second electromagnetic radiation returns;
• determining, using the controller, a scattering ratio from the comparing step;
• and
• applying, using the controller, the scattering ratio to a look-up table to identify a foreign object debris.

A system for particulate discrimination, comprising:

• a first electromagnetic radiation source operable to emit a first electromagnetic radiation pulse within a first wavelength range into a sensing volume;
• a first sensing element having a receiving cone defining a geometric volume that bounds the possible receipt paths of scattered electromagnetic radiations to sense reflections from the first electromagnetic radiation pulse from the sensing volume;
• a second electromagnetic radiation source operable to emit a second electromagnetic radiation pulse within a second wavelength range into the sensing volume, wherein the second wavelength range is within the terahertz (THz) regime in the wavelength range between 50 GHz (6 mm)-3 THz (0.1 mm);
• a second sensing element having a receiving cone defining a geometric volume that bounds the possible receipt paths of scattered electromagnetic radiations to sense reflections from the second electromagnetic radiation pulse from the sensing volume.