Abstract: [Subject] An object of the present invention is to provide a resonator readily achieving a high resonance frequency without extreme downsizing and allowing for a high Q factor. [Solving means] A resonator includes: a substrate serving as a base; a first beam having opposite ends fixed to the substrate via fixed connection portions, and having a vibration receiving location for providing linear reciprocating motion in a direction perpendicular to the longitudinal direction thereof; and second beams, branching toward one side from a plurality of branching locations different from the vibration receiving location in the first beam, for generating torsional vibration in accordance with the linear reciprocating motion. The resonator further includes a plurality of third beam, extending from the plurality of branching locations to a side opposite to the plurality of second beams, for generating torsional vibration.

Abstract: [Subject] An object of the present invention is to provide a resonator readily achieving a high resonance frequency without extreme downsizing and allowing for a high Q factor. [Solving Means] A resonator includes: a substrate serving as a base; a first beam having opposite ends fixed to the substrate via fixed connection portions, and having a vibration receiving location for providing linear reciprocating motion in a direction perpendicular to the longitudinal direction thereof; and second beams, branching toward one side from a plurality of branching locations different from the vibration receiving location in the first beam, for generating torsional vibration in accordance with the linear reciprocating motion. The resonator further includes a plurality of third beam, extending from the plurality of branching locations to a side opposite to the plurality of second beams, for generating torsional vibration.

Abstract: A micro mechanical resonator includes a high dielectric substrate, and a torsional vibrator having one end that is a fixed end fixed to high dielectric substrate, and having the other end that is a free end. The torsional vibrator has a substantially circular plate-like shape, has a lower surface serving as the fixed end fixed to the substrate, and has an upper surface serving as the free end that is not fixed. The torsional vibrator torsionally vibrates relative to an axis (torsional vibration axis) connecting the center of the circle of the end surface of the fixed end to the center of the circle of the end surface of the free end. In this way, a micro mechanical resonator can be implemented which can be manufactured readily and achieves a high Q factor.

Abstract: The intrusion detection system of the invention, in which three pyroelectric detectors are disposed in line with a interval and an adjoining two of the three pyroelectric detectors are electrically connected to cancel electrical charges generated by each pyroelectric detector, detects intrusion of an infrared ray radiating object such as a human body for example by output signals outputted from the adjoining two and the other of the three pyroelectric detectors or by output signals outputted from the pyroelectric detector disposed at the center and adjoining one and output signals outputted from the one disposed at the center and adjoining another one of these pyroelectric detectors, so that precise and secure intrusion detection is possible by reducing erroneous signals generated by those pyroelectric detectors due to variation of the atmospheric temperature and the like.