#407Diffraction Grating

White light through a ruled grating splits into ordered spectral fringes: the grating equation d·sinθ = mλ is inverted at every pixel, giving each diffraction order (m = 0 white, then ±1, ±2, ±3) its own continuous rainbow — violet nearest the axis, red farthest, brightness tapering with order. Scroll to change the line spacing d (wider fans, tighter rulings); move the pointer to tilt the angle of incidence.