Optical fibers in instrumental UV-analytics

Physical and optical properties of optical fibers have improved over recent years significantly. Especially classic UV detection techniques in traditional chemistry, HPLC and dissolution testing rely more and more on fiber optic light guiding techniques to transport light to and from a sample simplifying the design of such detection techniques. An overview on the current status of UV-fiber optical properties will be given in this work. Especially, the reduction of UV-defects in the 215 nm wavelength region leading to a lower drift in the whole system, will be discussed. However, these are not the only parameters of interest in a fiber-optic system. For process control or instrumental analytics, the long-term stability including drift and noise must be determined. This requires stringent fiber test procedures similar to light-sources, connectors and complete detector systems. Further, white-light interference between optical interfaces of a fiber optic detection system due to axial movement, degradation of components and temperature often reduces system stability and must be considered. Finally, a cleaning-in-process of a fiber optic immersion probe will be introduced as a further step of system improvement.