Non-lethal weapons are intended to have reversible effects on personnel and material. They provide soldiers with another option when lethal force isn’t considered to be the best first response to a situation. One non-lethal weapon prototype that is being evaluated by U.S. military is the Thermal Laser System, which attaches to a rifle and uses a laser to create a heating sensation to repel adversaries. Unfortunately, current trials indicate that clothing nullifies the weapon's effectiveness.

The U.S. military is well known for dreaming up new media-savvy euphemisms – ‘friendly fire’ was one of theirs – and the latest example is ‘escalation-of-force options’, which is what the Thermal Laser System and other non-lethal weapons are meant to provide. Like its predecessor, the PHaSR (seen in the image above), the Thermal Laser System is a man-portable non-lethal laser weapon system but, unlike the single-purpose PHaSR, is designed to attach to the standard rail system on military rifles and complement the existing weapon’s capabilities.

The effect of the Thermal Laser System is similar to Active Denial Technology, which heats the outer layer of the skin using short microwaves to safely repel individuals, but the Thermal Laser System uses an infrared laser instead. For the past several years, the Air Force Research Laboratory's Human Effectiveness Directorate Optical Radiation Branch has been investigating the bio-effects of these thermal lasers and its research has established the non-lethal operating window of laser power required to produce the desired reversible effect.

The system is currently undergoing field-testing by Joint Nonlethal Weapons Directorate (JNLWD), which has highlighted one of the problems with the system. While microwaves, such as those used in the Active Denial System, will go through any clothing and can only be stopped by wrapping oneself in tinfoil, the infrared of the Thermal Laser System can be blocked by clothing – fine if you’re trying to subdue a group of nudists, but problematic otherwise. The range of the weapon also hasn’t been revealed.

But that isn’t stopping the developers, who recognize the field-testing as an “invaluable tool in identifying improvements necessary before the Thermal Laser System reaches the hands of the warfighter.” In its favor though, they argue that the Thermal Laser System is a multi-shot weapon whose effects are “immediately reversible,” whereas Tasers and impact rounds can have more serious consequences.

According to Wesley Burgei, project engineer for the JNLWD, preliminary results of the field-testing suggest that the system may have military utility, however, researchers and the Services must still weigh this utility against the system's identified limitations.

Via Wired