Abstract: A piezoelectric thin-film resonator includes: a lower electrode supported by a substrate, a space being defined below the lower electrode; a piezoelectric film provided on the lower electrode and the substrate; and an upper electrode provided on the piezoelectric film so as to form a resonance portion in which the upper electrode faces the lower electrode across the piezoelectric film. At least one of the lower electrode and the upper electrode has an interconnection portion used to extract a signal from the resonance portion and located above the space. The at least one of the lower electrode and the upper electrode has a first mass per unit area in which the at least one of the lower electrode and the upper electrode contacts the piezoelectric film and a second mass per unit area in the resonance portion. The first mass per unit area is smaller than the second mass per unit area.

Abstract: An optical reader capable of reading a bar code in a mounted state when an article carrying the bar code passes and of reading bar codes set in array on a menu sheet in a hand-held state has been disclosed. The optical reader comprises a light source, a scanner that is driven by a drive and scans light emanating from the light source, a plurality of reflection mirrors that reflect scanning light scanned by the scanner and create a scanning pattern composed of a plurality of scan trajectories, a read window through which scanning light reflected from the reflection mirrors is emitted, and a light receiver for receiving light reflected from a mark. The optical reader further comprises a mode changer for changing a plurality of operation modes among which one or ones of the plurality of scan trajectories to be validated for reading are different.

Abstract: In a simulation considering a skin effect, a signal conductor is vertically and horizontally divided by faces parallel to the surface of the signal conductor, which are set so that intervals are smaller as the faces are nearer to the surface, and larger as the faces are farther from the surface. Also a ground conductor is vertically divided with a similar method, and an integration calculation is made, so that the resistance of the signal conductor, which corresponds to a given frequency, is obtained.

Abstract: An embedded electroconductive layer is disclosed which comprises an opening part or a depressed part 3 formed in an insulating film 2 on a substrate 1, a barrier layer for covering the opening part or the depressed part, a metal growth promoting layer 5 on the barrier layer, and an electroconductive layer 6 embedded in the opening part or the depressed part via the barrier layer 4 and the metal growth promoting layer 5.

Abstract: With regard to an optical communications system, in a system using a single optical fiber cable between subscribers and an exchange and in which bi-directional transmission is performed using the same 1.3-.mu.m wavelength, the exchange-to-subscriber signal is a high-speed, wideband signal which is bandwidth limited by means of a lowpass filter, and the subscriber-to-exchange signal is a carrier having a frequency higher than the upper limit of the exchange-to-subscriber signal and which is modulated with a low-speed, narrowband signal.