In recent years, the optical properties of the polyimide has attracted much attention. This is also due to the high thermal stability of polyimide, and engage in mechanical properties, ease of processing and structural characteristics due to easy cut. The so-called optical properties of a wide range, mainly refers to the transparent, specific refractive index, specific birefringent, nonlinear optical properties, electroluminescent or light-to-luminescent properties. For the latter two, polyimide mainly serving as a support group related functions. Polyimide structure itself functional relationship does not play a decisive role. However, these functions can maintain stability at higher temperatures. As for the photosensitive polyimide is a class action under the rays of light or partial introduction of the photosensitive polymer chain reaction. After development, the specific pattern obtained after the fixing, and then heat-treated to obtain a stable polyimide pattern of the polyimide precursor.
So far, the material for the transparent inorganic remains limited and general transparent polymer material. Such as polymethyl methacrylate, polystyrene, polycarbonate, and the like. Inorganic material optical loss minimum, glass fiber for long-distance transmission wavelength of 1310nm and 1550nm optical signal. Organic material loss at the wavelength of the much larger, but due to tough than glass and are increasingly being used for short and medium-distance connections. One disadvantage of such materials are sensitive to temperature, even at moderate temperatures, thermal stress can lead to local changes in the refractive index. Low glass transition temperature is more deformable material will occur, resulting in damage to the structure of the optical device.