Abstract: The apparatus for bleaching hair has a light comb with a comb back, a plurality of comb teeth extending from the comb back, a device for guiding light from a light source through the comb back into the comb teeth, and a device for radiating the light from the comb teeth and parallel to the comb back, this radiating device receiving the light from the light guiding device.

Abstract: The process for bleaching hair using light includes first, applying a sufficient quantity of a composition containing at least one optical photosensitizer and a compound capable of providing a hydrogen radical to strands of the hair to be bleached and allowing the composition to act for up to 60 minutes on those strands; then, irradiating them with light of a wavelength or wavelengths selected from visible and ultraviolet wavelength ranges capable of activating the at least one optical photosensitizer and having an intensity sufficient for bleaching them, and subsequently rinsing and drying the bleached hair. This process does not require excess hydrogen peroxide and is thus particularly gentle to the hair.

Abstract: A method of treating the surface of an optical structure which comprises forming on the surface a thin layer of organic polymer using a solvent casting technique. Preferably the process includes the subsequent treatment of the polymer layer with a solution of a specific ligand.Complex formation between the bound ligand and its specific binding partner present in a sample to be analyzed alters the optical properties of the diffraction grating surface and the change can form the basis of an assay method.