Mechanical Coupling Of An Iodine Laser Pulse Incident Obliquely On Aluminum

The total impulse delivered by an atomic iodine laser pulse ( λ= 1.315 μm) incident on sheet aluminum in air was measured as a function of angle of incidence. A moderate intensity (8x10 7 W/cm2) was obtained by focusing the pulse down to a 0.75 mm spot diameter. The aluminum target was mounted on a pendulum, and a sensitive inductive displacement monitor was used to measure accurately the resulting small impulse (<30 dyne-sec). The impulse, was found to decrease monotonically with inclination angle approximately as (cos 0)1/3.