De Broglie optics concerns the propagation of quantum mechanical particle waves, their reflection, refraction, diffraction and interference. The basic principles of De Broglie optics, which are quite similar to the principles of ordinary light optics, do not depend much on the specific nature of the sort of particles under consideration - electron, neutron, atom, ion, or molecule, but the focus in this chapter is on the De Broglie Optics of atoms and molecules. This sort of particles comes with a variety of internal degrees of freedom, which are easily addressed and manipulated with electromagnetic fields, in particular laser fields, and thereby allow for quite broad a spectrum of different applications in lithography, imaging and precision measurement.