Not a crowd pleaser (Image: Saul Loeb/Getty) Focused infrared beams produce a painful heat spot on an arm (Image: US Department of Defence) The latest version of the Department of Defence’s Thermal Laser System (Image: US Department of Defence)

THE Pentagon’s efforts to develop a beam weapon that can deter an adversary by causing a burning sensation on their skin has taken a step forward with the development of a small, potentially hand-held, version. The weapon, which is claimed to cause no permanent harm, could also end up being used by police to control civilians.

The idea of the weapon …