section_path: Optics
section_name: Optics
paragraph_text: Optics
  
  The study of light and the interaction of light and matter is termed optics. The observation and study of optical phenomena such as rainbows and the aurora borealis offer many clues as to the nature of light.
  
  A transparent object allows light to transmit or pass through. Conversely, an opaque object does not allow light to transmit through and instead reflecting or absorbing the light it receives. Most objects do not reflect or transmit light specularly and to some degree scatters the incoming light, which is called glossiness. Surface scatterance is caused by the surface roughness of the reflecting surfaces, and internal scatterance is caused by the difference of refractive index between the particles and medium inside the object. Like transparent objects, translucent objects allow light to transmit through, but translucent objects also scatter certain wavelength of light via internal scatterance.