The answer first noted that laser weapons are large. An anti-missile laser required a Boeing 747, the Navy set fire to a boat with a destroyer-mounted laser, and a dazzler-type laser called the PHaSR is as portable “as a bag of cement.”
Then, Straight Dope purchased a 1 watt blue handheld laser (the same or similar to the Wicked Lasers Spyder III Arctic). They aimed it at room temperature pork chops and bacon. From one foot away, it took 27 seconds of continuous exposure before smoke appeared. Even with matches, it took 11 seconds to light a match from one foot away, and 15 seconds from 32 feet away.
The January 6 2012 column concluded that handheld laser ray guns are not practical: “…the likelihood that this laser would actually change somebody’s mind (other than via intimidation alone) is virtually nil…. no bad guy is going to sit still while you fry him.”
Story and photos are at the Straight Dope website. The column was also printed in the Washington City Paper.
UPDATE: In comments at the Washington City Paper, “dave b” noted that exposure to skin isn’t necessarily the important factor: “The key is to get the laser into someone’s eye.”
For the military laser enthusiast, the catalog contains a number of other laser devices such as the AN/PEQ-14 Integrated Laser White Light Pointer (actually a white flashlight plus a visible and an invisible laser):
From the Program Executive Officer Soldier Portfolio FY2012 catalog. The LA-8/P is on printed pages 138-139, electronic pages 146-147. Originally found via GovWin.
Commentary from LaserPointerSafety.com: Although the LA-8/P Aircrew Laser Pointer does not emit a visible beam, it would be easy to make a visible version so that aircrews could “fire back” at persons on the ground aiming laser pointers at them. Whether this is a wise idea is another matter.
This was the only laser-related information in a December 15 2011 article that was otherwise about Iran tricking a U.S. drone into landing in Iran by jamming its GPS position signals.
From the Christian Science Monitor; the laser paragraph was on page 2 of the online story. See also an October 2011 Washington Post story analyzing a politician’s claim that China blinded U.S. satellites in 2006.
Concept of the rifle, from the Daily Mail
The developer is Photonic Security Systems, which also markets the rifle as a pirate deterrent. The Telegraph says that similar devices have been used in Afghanistan by NATO-led International Security Assistance Force troops.
PSS managing director Paul Kerr told the International Business Times "The very purpose of this technology is to be non-damaging … If someone is prepared to just stand there and stare down the barrel at this, which would be incredibly uncomfortable, then they are definitely a threat.” He said that he has often been exposed to the laser: "The quality and safety of the device is paramount and I know that first hand because I have been the guinea pig many times. I know what it is like and I know how effective it can be."
Author and activist Cory Doctorow points out that “the UK is a signatory on the Protocol on Blinding Laser Weapons … this weapon wouldn’t run afoul of international law if it (merely) reduced your vision to the point where you were impaired but not legally blind, permanently.” Doctorow also says “Twitter wags are already predicting a resurgence of mirrorshades [reflective sunglasses] among protesters.”
From the Telegraph, the Daily Mail, the International Business Times and BoingBoing. See related story on BAE Systems anti-pirate dazzler.
Black Hawk and Chinook helicopters have been testing a acoustic detection system called “Helicopter Alert and Threat Termination”, or HALTT. This uses microphones to detect the sound of a bullet or RPG. Delays in the sound reaching the microphones enables them to determine the sound’s location. A similar truck-mounted system is already in use. It can automatically swivel and fire a gun in the direction of the sound.
For helicopters, HALTT can be combined with guns and/or lasers. Infrared lasers help confuse missile guidance systems, while visible lasers would dazzle and flashblind anyone aiming at the helicopter. An engineer said the principle is to “make it impossible for a human to observe your aircraft … by creating a distracting light source. That has been done in the past and is a proven technology…”. The HALTT/laser countermeasure system could be in use by 2017.
The military already uses laser dazzlers at checkpoints, to warn approaching vehicles and to cause glare on anyone taking aim at soldiers.
From Wired and Defense Tech. A video of how the IR system would work against a missile is at YouTube.
During the U.S. phase of the Iraq war, Marine Corps leaders requested the handheld devices as a way to warn and stop drivers who were overrunning military checkpoints. Wired’s David Axe estimates that “as many as 50” Iraqi civilians were killed by gunfire -- instead of being forced off the road by dazzlers -- during the nine month delay.
There is some dispute over the safety of laser dazzlers. According to the Inspector General’s report,
Laser dazzlers provide a nonlethal capability by emitting an intense light capable of temporarily obscuring the vision of approaching individuals; however, using lasers poses a risk of serious eye injury and permanent blindness. This mode of employing a laser, shining a laser directly into the face or eyes, increases the inherent dangers of using the laser. Using nonlethal laser dazzlers would give Marine operating forces an additional capability to increase stand-off distances, safeguard civilians who venture too close to Marine positions, and help prevent unwarranted escalation of force incidences; however, DoD [Department of Defense] policy prohibits the use of lasers designed to cause permanent blindness. Operating procedures and laser safety measures are essential to ensure the safe and proper use of the lasers.
The Inspector General’s report contains additional details about the range, capabilities, safety concerns and policy issues related to military use of laser dazzlers. For example, the 1995 Protocol on Blinding Laser Weapons states that the signatories (which include the U.S.) “shall take all feasible precautions to avoid the incidence of permanent blindness to unenhanced vision.”
Roy Clarke, BAE Systems capability technology lead for laser photonic systems, said: “The effect is similar to when a fighter pilot attacks from the direction of the sun. The glare from the laser is intense enough to make it impossible to aim weapons like AK47s or RPGs, but doesn’t have a permanent effect.”
From the BAE Systems press release.