All lasers work by selective _____, a process that turns the light from the laser device into heat.

All lasers work by selective _____, a process that turns the light from the laser device into heat.

• A. Absorption
• B. Photothermolysis
• C. Reflection
• D. Diffraction

Answer: (B)

Selective photothermolysis is the concept tested. Lasers target specific tissues by using wavelengths that are preferentially absorbed by particular chromophores in the skin, such as melanin, hemoglobin, or water. That absorbed light is converted into heat, raising the target’s temperature and causing destruction where needed while leaving surrounding tissue relatively unharmed. The term photothermolysis captures this whole process: selective absorption of light followed by its transformation into heat to achieve controlled tissue damage. Absorption is part of what happens, but the key idea is the selective conversion of light to heat to achieve a therapeutic effect. Reflection and diffraction don’t produce this targeted heat-damage mechanism.

Selective photothermolysis is the concept tested. Lasers target specific tissues by using wavelengths that are preferentially absorbed by particular chromophores in the skin, such as melanin, hemoglobin, or water. That absorbed light is converted into heat, raising the target’s temperature and causing destruction where needed while leaving surrounding tissue relatively unharmed. The term photothermolysis captures this whole process: selective absorption of light followed by its transformation into heat to achieve controlled tissue damage. Absorption is part of what happens, but the key idea is the selective conversion of light to heat to achieve a therapeutic effect. Reflection and diffraction don’t produce this targeted heat-damage mechanism.