Monochromatic light falls on a transmission diffraction grating at an angle Φ to the normal.
(a) Show that Eq. 35–13 for diffraction maxima must be replaced by d(sinΦ + sinθ) = ±mλ. m = 0, 1, 2, ...
(b) Explain the ± sign.
(c) Green light with a wavelength of 550 nm is incident at an angle of 15° to the normal on a diffraction grating with 4500 slits/cm. Find the angles at which the first-order maxima occur.