Which characteristic of a laser can pose a significant risk to eye safety?

The characteristic of a laser that can pose a significant risk to eye safety is its wavelength and energy. Lasers emit light at specific wavelengths, and certain wavelengths can be particularly harmful to the eyes. For instance, lasers that emit in the visible spectrum, especially those with higher energy, have the potential to cause immediate damage to the retina if viewed directly.

Additionally, the energy of the laser is a critical factor in determining its risk level to eye safety. Higher-energy lasers can deliver enough power to cause thermal damage or even cataracts to the eye tissue upon exposure. This is why understanding the interplay of wavelength and energy is vital for assessing risks associated with laser use and ensuring adequate safety measures, such as protective eyewear or distance from the laser source, are in place. Other characteristics, such as portability, cost, or weight, do not directly influence the immediate hazards posed by laser exposure to the eyes.