AAWSAP DIRD, State of the Art and Evolution of High-Energy Lasers, March 2010
DOW-UAP-D137 · page 7 of 31
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---------------------------------------------- ---------------------------------------------- ---------------------------------------------- UNCLASSIFIED/fFOA OFFl&I.t.k YSE &P•tv HEL and Kinetic Weapons offer complementary capabilities Soft/Small/Fast Moving/tactical Missiles & Hardened or E/O sensors Vehicles Satellites Large Area (Dazzle or Destroy) Cell towers & comm nodes ICBMs Tanks Target Types Target tagging Fire starting Small UAVs Radar antennas Power grids Ceramic RF radornes IRBMs TheaterBMs Cruise missiles Armored vehicles Bridges Buildings Manpads MilitaryUAVs Individual persons Satellites Groups of people Rockets, artillery & mortars - Laser Power Increasing Laser Power or Increasing Range for Same Effect ---+ Laser 1 kW Weapon Effectiveness E asy 10kW 100kW Medium 111Ni Difficult Impractical Medium Easy KE Impractical Weapon if stationary Difficult If stationary if isolated Effectiveness if isolated Figure 1. Utility of KE and HEL Weapons ELEMENTS OF AN HEL WEAPON The purpose of an HEL weapon system is to place and maintain the focused laser beam on a target aim point for sufficient time to cause the desired heating effect. To accomplish this, the weapon beam is generated by the laser device, then shaped and relayed to the input of a pointing telescope (Figure 2). Laser beam sensors and steering mirrors are required to maintain the HEL beam centered as it traverses the optical train. The pointing telescope, which typical ly sits on azimuth and elevation gimbals, then expands the beam to the diameter of its primary mirror and focuses it to the range of the target while an imaging system (which can use a separate telescope or share the transmitting telescope) acquires the target, tracks it, and points the transmitting telescope's beam at the desired aim point. If the HEL beam's propagation path from the weapon to the target includes the earth's atmosphere, it can have a significant deleterious effect. Absorption and scattering of the beam, which reduce its strength at the target, are caused by molecular constituents of the atmosphere and aerosols such as haze or dust. Additionally, atmospheric turbulence spreads the focused spot and further reduces its effectiveness. All of these factors must be taken into account when designing a laser weapon. UNCLASSIFIED/fFOA QFFI&I.t.k YSE 8,.L\f 2