from the popping-balloons dept.
"Our results show that the so-called 'frequency doubled' laser pointers, usually green, blue and violet pointers, can be particularly dangerous even if they seem safe to the user," he said.
"For example, some laser pointers can output widely different laser power depending on the temperature. They can appear perfectly safe at room temperature only to become much more dangerous outside and vice-versa. Moreover, as pointers are being used they heat up, so a pointer that initially seems safe can subsequently become highly powerful and dangerous.
"Other lasers can produce safe levels of coloured light, but at the same time emit high power invisible infrared light. A person looking at the visible green light would estimate the laser to be safe and the much greater power and danger would go unnoticed until injury occurs."
Laser pointers have been controversial, in particular because they have been shined into the eyes of plane and helicopter pilots and train drivers, with an average of 1,500 reported attacks per year in the UK. They can cause permanent or temporary eye damage, and it is a criminal offence to do so.
If they're so dangerous, why are they putting them in the headlights for all the new cars?