Diffuse reflection diameter in simple polygons

We prove a conjecture of Aanjaneya, Bishnu, and Pal that the minimum number of diffuse reflections sufficient to illuminate the interior of any simple polygon with nn walls from any interior point light source is ⌊n/2⌋−1⌊n/2⌋−1. Light reflecting diffusely leaves a surface in all directions, rather than at an identical angle as with specular reflections.