Abstract: A wireless communication device is provided and includes: a first communication processing unit performing communication in an electromagnetic induction system by using a first antenna unit; a second communication processing unit performing communication at higher speed than the first communication processing unit by a system or a communication frequency different from the electromagnetic induction system by using a second antenna unit; and a power generation unit generating power at least for performing communication operations from a carrier signal received by the first antenna unit. The power is generated in the power generation unit by switching a frequency resonance characteristic of the first antenna unit.

Abstract: A method and apparatus for controlling the focal position of the UV light for auto-focussing the converged UV light, and a method and apparatus and for inspecting a device, such as a semiconductor wafer or liquid crystal using the converged UV light, in which the UV light converged is to be auto-focussed accurately and speedily. The method includes an inspection stage 11 for supporting a semiconductor wafer, an objective lens for UV light 40 or converging a UV laser light for illuminating the laser light converged to the semiconductor wafer, a distance sensor 41 secured to this objective lens for UV light 40 to detect the distance to the semiconductor wafer and a controller for causing movement of the inspection stage 11 in a perpendicular direction. The controller causes the distance between the objective lens for UV light 40 and the semiconductor wafer to coincide with the target distance T based on the distance as detected by the distance sensor 41.

Abstract: For effecting auto-focussing of an objective lens used for observing a semiconductor wafer, a semiconductor microscopic device includes an inspection stage for supporting a semiconductor wafer and an objective lens for observing the semiconductor wafer. For automatic focussing of the objective lens, a defocussing magnitude of a light spot is detected using a knife edge. A collimator lens is oscillated by a voice coil motor to oscillate the light spot on the wafer. A peak value of the defocussing quantity detected at this time is peak-held to generate a position detection signal. The inspection stage is vertically moved so that this position detection signal will be equal to a pre-set target value.

Abstract: The displacement measuring apparatus of a laser interference technology includes a probe 3 which delivers at a photodetector 17 an RF signal of which a modulated component proportional to a displacement of an object 2 under measurement. The apparatus has also a phase-demodulation circuit 9 in which an interference signal produced by shifting the frequency of the RF signal to an intermediate frequency is phase-demodulated on the basis of the carrier signal for supply to a light modulator 16. Thus the apparatus can detect a displacement of the object with a high resolution.

Abstract: A laser Doppler speed measuring apparatus comprises a laser light source, a photodetector, an FM demodulator, and an integrated filter circuit. A selector switch is interposed between the FM demodulator and the integrated filter circuit so as to ensure switching between an output of the FM demodulator and a terminal for directly receiving an external signal.