Jay Brown

Requesting help with units of angular dispersion for reflection grating

Discussion created by Jay Brown on Oct 3, 2013
Latest reply on Dec 5, 2013 by Jay Brown

Dear ACS members,


Could someone please explain the units of angular dispersion for a reflection grating? The equation is Da = n / d * cos(r). An optics book listed the units: Da is angular dispersion (radians/nm), n is the reflection order (unitless), d is the spacing between rulings (nm), cos(r) is the cosine of the reflected angle, and r is the reflection angle (degrees). I do not understand where the radians come from in the result given the units of the calculation. This is the only book I could find the units specifically listed. Is this a misprint?


Thank you,


Jay Brown