Substrates such as transparent glass layers or other transparent substrates may be used to form protective display cover layers, windows, housing structures, camera windows, and other structures. Coatings may be formed on the substrates, on pixel arrays such as flexible organic light-emitting diode pixel arrays, housing structures, and other structures. The coatings may have optical properties arising from the inclusion of pigment flakes in a clear polymer binder. The pigment flakes may be formed from a thin-film interference layer. The thin-film interference filter layer may have a stack of dielectric layers with a pattern of refractive index values selected to adjust the optical properties of the pigment flakes. The stack of dielectric layers may be configured to form an infrared-light-blocking-and-visible-light-transmitting optical characteristic for the coatings and/or may have other desired spectral properties.