Abstract: Optical microphone, laser-based microphone, and laser microphone having reduced-noise components of low-noise components. A laser microphone comprises a laser-diode associated with a low-noise laser driver TX; and a photo-diode associated with a low-noise photo-diode receiver RX. The low-noise laser driver TX supplies a drive current which is a combination of a Direct Current component having a first bandwidth, and an attenuated version of an Alternating Current component having a second, different, bandwidth. Additionally or alternatively, the low-noise photo-diode receiver RX utilizes hardware-based demodulation of the analog signal, and operates to remove a Direct Current component of its output signal prior to digitization.

Abstract: Optical microphone, laser-based microphone, and laser microphone having reduced-noise components of low-noise components. A laser microphone comprises a laser-diode associated with a low-noise laser driver TX; and a photo-diode associated with a low-noise photo-diode receiver RX. The low-noise laser driver TX supplies a drive current which is a combination of a Direct Current component having a first bandwidth, and an attenuated version of an Alternating Current component having a second, different, bandwidth. Additionally or alternatively, the low-noise photo-diode receiver RX utilizes hardware-based demodulation of the analog signal, and operates to remove a Direct Current component of its output signal prior to digitization.

Abstract: A resonance locking system for a pico-projector, the system comprising a resonance frequency sensor operative for sensing change in resonance frequency of a miniature mechanical device (10) including a moving mirror assembly having a driving frequency, by comparing a current resonance frequency to a reference; and a feedback loop changing at least one aspect of use of the miniature moving mirror assembly responsive to a current value of the resonance frequency measured by the sensor.

Abstract: A resonance locking system for a pico-projector, the system comprising a resonance frequency sensor operative for sensing change in resonance frequency of a miniature mechanical device (10) including a moving mirror assembly having a driving frequency, by comparing a current resonance frequency to a reference; and a feedback loop changing at least one aspect of use of the miniature moving mirror assembly responsive to a current value of the resonance frequency measured by the sensor.

Abstract: A non-contact printed circuit board (PCB) electromagnetic testing system comprises at least one high resolution transducer operative to induce multi-frequency, multi-amplitude eddy currents in a tested PCB, each such transducer including both a high frequency excitation coil that serves also as a sensing coil and a direct current (DC) bias coil operative to provide an optimal transducer operating regime; a multi-frequency generator for providing AC and DC bias signals to each transducer; and a control mechanism for driving the transducer. Optionally, the system further comprises an external ferrite concentrator that enhances a magnetic field flux focus and depth of focus on the inspected PCB. The multi-frequency, multi-amplitude methods enable three-dimensional mapping of various features in the PCB with both high sensitivity and high resolution in respective operating regimes.

Abstract: A non-contact printed circuit board (PCB) electromagnetic testing system comprises at least one high resolution transducer operative to induce multi-frequency, multi-amplitude eddy currents in a tested PCB, each such transducer including both a high frequency excitation coil that serves also as a sensing coil and a direct current (DC) bias coil operative to provide an optimal transducer operating regime; a multi-frequency generator for providing AC and DC bias signals to each transducer; and a control mechanism for driving the transducer. Optionally, the system further comprises an external ferrite concentrator that enhances a magnetic field flux focus and depth of focus on the inspected PCB. The mutli-frequesncy, multi-amplitude methods enable three-dimensional mapping of various features in the PCB with both high sensitivity and high resolution in respective operating regimes.

Abstract: A system for preventing damage to the eyes of a person being within a certain distance from a high-power laser, including a device for ascertaining the absence of a person within this range, and a device for actuating the high power laser only if the results indicate that no such person is present in the specified range. There is also provided a method for eye protection against damage by high-output lasers, which comprises examining such a range with a low power laser or other similar device, harmless to a person's eyes within the specific range, and for actuating high power laser radiation only after a clear indication that no person is present within the dangerous range.