Abstract: An optical instrument may include a tunable free-space filter as a wavelength selector. That optical instrument may be an optical spectrum analyzer (OSA). Indeed, the OSA may be constructed and arranged as an optical channel monitor for wavelength-division multiplexed optical communication systems. The tunable free-space filter may be a tunable thin film filter (TTFF). The TTFF may be thermo-optically tunable. The tunable filter may be a multi-layer film structure incorporating thin film semiconductor materials. The temperature, and hence the wavelength, of the TTFF may be controlled by various heating and cooling structures. Various TTFF structures are also possible. The TTFF may have a single-cavity Fabry-Perot structure or may have a multi-cavity structure. Packaging variants can also be made. Any one or more of several calibration aids can be included, such as an external source of one or more known wavelength signals, or an internal source of one or more known wavelength signals.

Abstract: An improved tool for extracting the base of a broken light bulb from a socket. An integral device has a cylindrical stem portion with an enlarged handle at one end and a tapered conical portion with a flat tip at the other. The tapered conical portion has toothed blade members embedded in slots thereon, with the toothed edges facing outward. Two such blades are longitudinally disposed at diametrically opposed locations of the conical portion, and a shorter blade member is horizontally disposed on the flat tip thereof.