Rowland circle
(also Rowland's circle) Physics
noun
A circle on which the slit, (concave) diffraction grating, and detector of a spectrograph must all lie if all the spectral lines are to be brought to a focus on the detector.
- The circle has a diameter equal to the radius of curvature of the grating surface and is tangential to the grating at its midpoint..
Origin
Early 20th century; earliest use found in Astrophysical Journal.