Which type of laser generally presents the least risk of eye injury?

Class 1 lasers are classified as safe under all conditions of normal use, making them the type that presents the least risk of eye injury. These lasers emit low levels of energy and are designed to be incapable of causing harm, even when viewed directly. This classification typically includes lasers found in everyday devices, such as laser printers and CD players, which are designed to prevent exposure at harmful levels.

The safety of Class 1 lasers is due to their limited accessibility to hazardous levels of laser radiation, as they operate below the emission threshold that would pose a risk to human eyesight. In contrast, other classes, such as Class 3 and Class 4 lasers, have higher power levels and can potentially cause eye damage, either through direct exposure or reflections. Class 2 lasers, while considered safe for short exposure times because they emit visible light, can still cause harm if viewed for extended periods. Thus, Class 1 lasers are unequivocally the safest option regarding eye safety.