The interaction of light and matter
What happens when a light ray hits a
point on an object?
•Some of the
light gets absorbed
–converted to
other forms of energy (e.g., heat)
•Some gets
transmitted through the object
–possibly
bent, through “refraction”
•Some gets
reflected
–as we saw
before, it could be reflected in multiple directions at once
Let’s consider the case of reflection
in detail
•In the most general
case, a single incoming ray could be reflected in all directions.
How can we describe the amount of light reflected in each direction?