system
Given the following post, respond as if you're commenting on Reddit:
human
Why is diffuse reflection a hazard of working with lasers?

Moreover, how can surfaces that appear shiny be diffuse reflectors of UV wavelengths? Also, how can surfaces that appear dull be specular reflectors of IR wavelengths? What is about those wavelengths that allow them to act differently on those types of materials?
gpt
A surface consisting of microscopic features may work like a mirror for wavelengths larger than these features. So actually IR and UV are not special, they react the same way to surfaces structured relative to their respective wavelengths.