Diffractive Optics

When the angles of light propagation after the diffractive element are small (roughly less than ten degrees), we can base the design on scalar diffraction theory and apply the Iterative Fourier Transform Algorithm (IFTA). With this method, we can design beam shapers such as flat-tops (round, square, rectangular), homogenizers (diffractive diffusers), and beam splitters.

All design tasks are negotiated on a case-by-case basis.

For the designs, we use IFTA codes written in-house, contact Pertti Pääkkönen

When large deflection angles are required, we must apply rigorous diffraction theory. Typically, these elements, such as beam splitters, are polarization dependent, but they can also be designed for unpolarized light, as in the case of spectrometer gratings. For periodic structures the Fourier Modal Methods are particularly effective. In designs, the gratings can be combined with a thin film stack to create, for example, a wavelength-selective laser mirror.

All design tasks are negotiated on a case-by-case basis.

For the designs, we use Fourier Modal Method (FFM) codes written in-house; contact Pertti Pääkkönen.

Alternatively, we can use Gsolver software based on Rigorous Coupled Wave Analysis; contact Aki Mäyrä.