Fabricating of integrated optics

Abstract

Method for fabricating components for integrated optics are provided wherein a film of polystyrene doped with methyl red (PS-MR) on a glass substrate, is masked, e.g. with one or more metallic strips on a glass plate and such film is irradiated with, e.g. a UV lamp, tuned within the absorption band of such film, in air, to photobleach the film portions around channels covered by the masking strips and reduce the refractive index thereof below that of the unbleached film channels. The bleached film portions then provide reflective beam confining interfaces which define the unbleached channels and form waveguides within the film. The invention also provides for interfering two laser beams of like .lambda., at a coupling spot on the film, which beams are again tuned within the absorption band of such film, which bleach alternate lines or bars of such film to provide a phase grating therein. A waveguide can be inscribed in such film to optically communicate with such phase grating and other components can be added such as optical interconnects, to direct light on various paths into and out of such integrated optical film circuit. The thus-formed circuit is preserved by encapsulating the so-bleached film in a layer of, e.g. epoxy at a lower index of refraction than the unbleached film, while the glass substrate protects the reverse face of such film, which glass also has a lower index of refraction than the unbleached film so that the optical components of the invention, e.g. the waveguides, are enclosed on all sides by reflective interfaces of lower index of refraction to confine and channel transmitted light therein. The light can enter and exit the integrated optical circuit of the invention at a phase grating or where the waveguides reach the film edges. The invention takes advantage of photobleaching to change the index of refraction of portions of a thin film to define optical components therein and has located a class of films, including PS-MR, which, upon photobleaching, provide a considerable reduction in refractive index, enabling the definition of optical components in such film. The invention includes the methods of fabricating such integrated optics as well as the integrated optic products so-made.

Dependencies are inferred from the claim text.