Abstract: In a hermetically sealed container constituted by a lid (105), frame (103), and substrate (104), a piezoelectric vibrator (101) is fixed on the substrate (104) (on the upper surface of the substrate) with fixing members (104a) made of a conductive material, and a semiconductor component (102) is flip-chip mounted on the lower surface of the substrate (104).

Abstract: Since etching of a crotch portion of quartz vibrator defined by segment 18, first segment 13, and second segment 17 advances in accordance with the crystal orientations of quartz, the shape of side surfaces of two quartz vibrating bars opposite to each other with this crotch portion in between can be made symmetric, whereby stress applied on the two quartz vibrating bars can be equalized.

Abstract: In a surface acoustic wave device for processing signals of relatively high frequencies, as of above 1 GHz, by the use of surface acoustic waves which propagate on the surface of a piezoelectric substrate, radiating bulk waves in the direction of depth of the piezoelectric substrate, an IDT structure is provided, which does not increase propagation loss and has sufficiently low electric resistance. The device comprises a piezoelectric substrate 10, and an electrode of a conducting film 12 for exciting, receiving, reflecting and/or propagating surface acoustic waves, and the surface acoustic waves propagate on the surface of the piezoelectric substrate, radiating at least one transverse component of bulk waves in the direction of depth of the piezoelectric substrate 10.

Abstract: A surface acoustic wave filter comprises a first electrode structure array which is formed on the piezoelectric substrate, and includes an input/output IDT, two receipt IDTs formed outside the input/output IDT and two reflectors formed outside the two receipt IDTs, and a second electrode structure array which is formed on the piezoelectric substrate and includes an input/output IDT, two receipt IDTs formed outside the input/output IDT and two reflectors formed outside the two receipt IDTs, which are concatenated with each other. In a case that the surface acoustic wave filter is represented by a symmetrical lattice-type circuit which is expressed by a serial arm impedance and a parallel arm impedance and is electrically equivalent to the same, at least two resonances of the serial arm impedance and at least three resonances of the parallel arm impedance are used to form a passband. The surface acoustic wave filter can have wide bands and low spurious signal.

Abstract: A first electrode structure row formed on a piezoelectric substrate, and including N1 pairs of an input/output IDT, N2 pairs of a connection IDT, and reflectors is cascade-connected to a second electrode structure row formed on the piezoelectric substrate, and including N1 pairs of an input/output IDT, N2 pairs of a connection IDT, and reflectors, the connection IDT of the first electrode structure row, and the connection IDT of the second electrode structure row being arranged electrically symmetric with respect to the cascade-connected plane. The pair number N1 of the input/output IDT is different from the pair number N2 of the connection IDT. When a normalized electrode film thickness of the input/output IDT and the connection IDT is represented by h/L, the pair number N1 of the input/output IDT satisfies the following formula43-11(h/L).ltoreq.N1.ltoreq.61-11(h/L).

Abstract: A retina direct display device provides an observer with the display of a plane image or a stereoscopic image. The retina direct display device is, for example, incorporated with an acoustic device to constitute a television receiver. The retina direct display device comprises a visible light conversion means, a retina projection means and an eye movement tracking means. The visible light conversion means converts an input video signal to a beam of visible light. The retina projection means deflects the beam horizontally and vertically so that retinas are raster scanned through pupils of both eyes by the deflected beam. The eye movement tracking means detects the movement direction of the pupils and permits the direction of the beam emitted from the retina projection means to track the movement of the pupils based on the result of the detection.

Abstract: According to this invention, an SAW electric part includes an SAW filter and an SAW oscillator formed on a substrate having the same temperature characteristics as those of a substrate on which the SAW filter is formed. A frequency converter includes the SAW electric part, a second local oscillation circuit, a frequency converter, a first mixer, and a second mixer. The second local oscillation circuit oscillates a second local oscillation signal using the SAW oscillator. The frequency converter converts a frequency of the second local oscillation signal to generate a first local oscillation signal. The first mixer mixes the first local oscillation signal with an input signal to output a composite signal to the SAW filter. The second mixer mixes an output from the SAW filter with the second local oscillation signal to output a frequency conversion signal.

Abstract: A band-pass filter includes a first filter, a second filter, and switching elements. The first filter is constituted by a plurality of filter elements. The second filter is constituted by a plurality of filter means and connected in series with the first filter. The switching elements can short-circuit either one of the first and second filters.