Diffraction efficiency is the performance of
diffractive
Diffraction is defined as the interference or bending of waves around the corners of an obstacle or through an aperture into the region of geometrical shadow of the obstacle/aperture. The diffracting object or aperture effectively becomes a s ...
optical elements – especially
diffraction grating
In optics, a diffraction grating is an optical component with a periodic structure that diffracts light into several beams travelling in different directions (i.e., different diffraction angles). The emerging coloration is a form of structura ...
s – in terms of
power
Power most often refers to:
* Power (physics), meaning "rate of doing work"
** Engine power, the power put out by an engine
** Electric power
* Power (social and political), the ability to influence people or events
** Abusive power
Power may a ...
throughput. It's a measure of how much optical power is diffracted into a designated direction compared to the power incident onto the diffractive element of grating.
If the diffracted power is designated with
and the incident power with
the efficiency
reads
:
Grating efficiency
In the most common case – the diffraction efficiency of optical gratings (therefore also called ''grating efficiency'') – there are two possibilities to specify efficiency:
*The ''absolute efficiency'' is defined as above and relates the power diffracted into a particular order to the incident power.
*The ''relative efficiency'' relates the power diffracted into a particular order to the power that would be reflected by a mirror of the same coating as the grating, therefore attributing to inevitable reflection losses at the grating but not caused by inefficient diffraction itself.
References
External links
*{{cite web , url=https://www.gratinglab.com/Information/Handbook/Handbook.aspx , title=Efficiency Characteristics of Diffraction Gratings , author=Christopher Palmer , year=2020 , work=Diffraction Grating Handbook (8th edition) , publisher=MKS Newport , accessdate=13 March 2020
Diffraction