The Directed Energy Test and Evaluation Capability (DETEC) Lead Systems Integrator (LSI) completed work on the High Energy Laser (HEL) Ground Target Irradiance Measurement (GTIM) Capability. The HEL GTIM Capability measures continuous wave (CW) laser irradiance in the near infrared (NIR) portion of the spectrum (1.0 µm – 1.6 µm) for a laser incident on a target. The HEL GTIM Capability is designed for use during lethality testing against realistic targets and can accommodate both airborne and ground-based HEL weapons. The system consists of a rotating spoke apparatus mounted on a mast, an imaging system, and a portable computer for downloading and analyzing data in the field. The entire system is mounted on a wagon that can be easily towed. The mast can be adjusted through four degrees of freedom: three rotational and one translational. These allow test range technicians to easily position the mast with the rotating spoke apparatus and the imaging system and align it with the laser beam without having to move the entire wagon.

The system samples 5% of the power in the incident beam in making measurements. This allows the T&E community to conduct lethality testing while the HEL beam is being sampled in a way that does not affect the beam or the response of the target. The HEL GTIM system eliminates the uncertainty associated with the current technique of sampling the beam during one dwell, recording effects on the target during another dwell, and trying to correlate the effects by assuming the two beam profiles are identical.

Programs wishing to use the HEL GTIM Capability should contact Mr. James Andersen, High Energy Laser Systems Test Facility (HELSTF) Test Operations Manager, at (575)679-5123 or James.Andersen1@us.army.mil.

Scientific Applications and Research Associates, Inc. (SARA) of Cypress, CA developed the HEL GTIM Capability under subcontract.