A molded plastic panel has microscopic ridges spaced about 8μm apart. The panel is illuminated separately by two monochromatic beams:
(I) violet light with wavelength λ1=400nm
(II) far-infrared radiation with wavelength λ2=16μm
Which combination of reflection types is most likely observed from the panel?
a) (I) specular,(II) diffuse
b) Both diffuse
c) (I) diffuse,(II) specular
d) Both specular