Bilayer structures consisting of organic dye/polymer binder systems solvent-coated on reflective substrates are useful for real-time high-density optical recording. Information is recorded by using focused actinic light that is highly absorbed in the vicinity of the surface of the dye/binder layer. Recorded marks consist of steep-walled flat-bottomed depressions or ’’pits’’ that have depth designed to impart a phase shift of ∠r/2 to a focused readout light beam having a wavelength at which the dye/binder layer is essentially transparent. The optical and physical characteristics of these structures that lead to good recording sensitivity and high levels of playback performance are discussed.