In theory, 2 Types of reflectance surface:
1) Specular reflection (เรขาคณิต)
for smooth and flat surface
2) Diffuse reflection (ฟุ้งกระจาย)
for rough surface
Reflections known in nature:
a) Perfect specular reflector;
b) Near-perfect specular reflector;
c) Near-perfect diffuse reflector;
d) Perfect diffuse reflector.