Which materials absorb laser energy and heat up the most?

• A. Lighter colored solids
• B. Darker colored solids
• C. Transparent gels
• D. Metal powders

Answer: (B)

When laser energy shines on a material, how hot it gets depends on how much of that light energy the material absorbs. Absorbed light is converted into heat, so higher absorption means more heating under the same laser conditions.

Darker colored solids absorb more of the incident light than lighter colored ones because pigment and color determine how much light is reflected versus absorbed. The darker the color, the less light is reflected and the more energy is absorbed, causing a greater temperature rise.

Transparent gels, by contrast, let most of the light pass through with little absorption, so they heat up less under the same laser exposure. Metal powders often reflect a large portion of light due to the reflective nature of metals, so they typically absorb less energy than dark pigments and heat less under common laser wavelengths.

Thus, darker colored solids heat up the most because they absorb more of the laser energy.