TiO₂
Si
GaN
Si₃N₄
GaAs
Cylinder
Square
Ellipse
Rectangle
Cross
Propagating
Geometric (PB)
0%
–
–
–
µm
–
µm
–
%
–
µm
–
nanometre (nm)
micrometre (µm)
millimetre (mm)
Multifocal
Optical vortex (OAM)
Bessel beam
Airy beam
Helical