Academics Archives - EMPossible

Ever wonder why diffraction order exist only at discrete angles?

Posted October 6, 2020March 26, 2021 EMProfessorPosted in Academics

Check out the visualization below – it can help explain why diffraction orders, or grating lobes, exist only at discrete angles. Waves that are reflected from (or transmitted through) a periodic structure take on the same period as the structure. The field must also be continuous. Only certain discrete angles allow the field to be […]

Direction of diffraction orders from crossed diffraction gratings

Posted March 28, 2020October 6, 2020 EMProfessorPosted in Academics, General

Diffraction gratings are common optical elements in spectrometers, fan-out gratings, dichroic mirrors, and other filter devices. One common aspect of all of these is that they split an incoming wave into multiple diffraction orders. The direction of the diffraction orders depends on the angle of incidence and period of the grating relative to the wavelength. […]