An optical device includes an array of light-emitting elements, including a first subset of light-emitting elements and a second subset of light-emitting elements. The first subset of light-emitting elements is configured to emit light having wavelength L1. The device includes a high refractive index material selectively disposed on the second subset of light-emitting elements and an array of optical elements positioned so as to be illuminated by the first subset of light-emitting elements and by the second subset of light-emitting elements. The optical elements are regularly arranged in a common plane at a pitch P, the common plane is located a distance D from the array of light-emitting elements, and P2≈2L1D/N, N being an integer greater than or equal to 1.