A resist composition has a polymer containing a carboxyl group with a protective group at a side chain of a monomer unit, the polymer being insoluble to basic aqueous solution and becoming soluble to basic aqueous solution when the protective group of the carboxyl group is eliminated from the side chain, the protective group of the carboxyl group being represented by: . As a result, an optical adddrop multiplexer may be provided that can be tuned to select a desired wavelength. The first region comprises a fan-shaped truss comprising a hub adjacent the first flange and a plurality of struts which extend substantially radially from the hub, and the second region comprises either a truss structure which is substantially regular in the longitudinal beam direction or a shear web. If there is any abnormality data, it transmits a tire air pressure abnormality signal to the portable device.