Abstract: A chemically sensitive sensor capable of detecting changes in concentrations of ions, atoms, or molecules in a fluid environment in which the sensor is immersed or embedded comprises a thin clad optical fiber, which is coated with a polymer which is permeable to liquids and which contains a chemically sensitive material, and a light carrying fiber. The polymeric material has the ability to change color and/or absorbance when the concentration of the ion, atom, or molecule in the surrounding environment changes. The polymer will return to its original color and/or absorbance state once the concentration goes back to the original value. The color change or absorbance is detected through the core of the optical fiber which is connected to a photodetector. The coupling of the light into the sensing structure is obtained by using a core-only optical fiber, surrounded by a clad material, in addition to an external light source.

Abstract: Optical interconnectors and methods for optically interconnecting structures, such as printed circuit boards. The optical interconnectors comprise at least two optical fibers having one end embedded in a structure such as a printed circuit board and at least one sleeve for housing termination portions of two optical fibers. The termination portions of the fibers are positioned and secured within the sleeve so that end surfaces of the optical fibers are abutted together. The resulting optical interconnectors have low loss and occupy a small amount of space while maintaining a flat profile.