The present description concerns a microelectromechanical sensor control method, including the steps of: exciting, with same first signal (FSL), a first resonant (206L) and at least one second resonant element (206R); and estimating a phase shift (Δφ) between the first signal and a second signal (FSR) which is an image of vibrations of the second resonant element.

A lidar system includes a laser diode to provide a frequency modulated continuous wave (FMCW) signal, and a current source to provide a drive signal that modulates the laser diode. The current source is controlled to pre-distort the drive signal to provide a linear FMCW signal. The lidar system also includes a splitter to split the FMCW signal into an output signal and a local oscillator (LO) signal, a transmit coupler to transmit the output signal, a receive coupler to obtain a received signal based on reflection of the output signal by a target, and a combiner to combine the received signal with the LO signal into first and second combined signals. A first and second photodetector respectively receive the first and second combined signals and output first and second electrical signals from which a beat signal that indicates the pre-distortion needed for the drive signal is obtained.

A lidar system includes a photonic chip including a light source and a transmit beam coupler to provide an output signal for transmission. The output signal is a frequency modulated continuous wave (FMCW) signal. A transmit beam steering device transmits the output signal from the transmit beam coupler of the photonic chip. A receive beam steering device obtains a reflection of the output signal by a target and provides the reflection as a received signal to a receive beam coupler of the photonic chip. The photonic chip, the transmit beam steering device, and the receive beam steering device are heterogeneously integrated into an optical engine.

A sound producing device includes a first sound producing cell, driven by a first driving signal and configured to produce a first acoustic sound on a first audio band, and a second sound producing cell, driven by a second driving signal and configured to produce a second acoustic sound on a second audio band different from the first audio band. A first membrane of the first sound producing cell and a second membrane of the second sound producing cell are Micro Electro Mechanical System fabricated membranes. The first audio band is upper bounded by a first maximum frequency; the second audio band is upper bounded by a second maximum frequency. A first resonance frequency of the first membrane is higher than the first maximum frequency of the first driving signal. A second resonance frequency of the second membrane is higher than the second maximum frequency of the second driving signal.

A method for detecting contamination of a microelectromechanical sensor element. The method includes the following steps: outputting heating control signals for controlling a heating device in order to heat the sensor element, receiving measuring signals that represent a physical variable that is measured with the aid of the heated sensor element, ascertaining, based on the measured physical variable, whether the sensor element has contamination or is free of contamination, outputting result signals that represent a result indicating whether the sensor element has contamination or is free of contamination. Moreover, a device is described.

A method for tuning one or more sensor devices is provided, wherein each sensor device comprises one or more proof masses configured to move in response to an external stimulus of interest, and the one or more proof masses are also susceptible to move in response to one or more stimuli other than the external stimulus of interest. Each sensor device also comprises one or more pick-off mechanisms respectively associated with each of the one or more proof masses. The one or more pick-off mechanisms is proportionally responsive to a motion of the sensor device. The method for tuning includes adjusting gain of one or more of the pick-off mechanisms to reduce an output of each sensor device when the one or more proof masses move in response to the one or more stimuli other than the external stimulus of interest.

A device includes a micro-electromechanical system (MEMS) device layer comprising a proof mass. The proof mass includes a first proof mass portion and a second proof mass portion. The first proof mass portion is configured to move in response to a stimuli. The second proof mass portion has a spring attached thereto. The device further includes a substrate disposed parallel to the MEMS device layer. The substrate comprises a bumpstop configured to limit motion of the first proof mass portion. The device includes a first electrode disposed on the substrate facing the second proof mass portion. The first electrode is configured to apply a pulling force onto the second proof mass portion and to move the second proof mass portion towards the first electrode.

A sensor system includes first and second MEMS structures and a processing circuit. The first and second MEMS structures are configured to produce first and second output signals, respectively, in response to a physical stimulus. A method performed by the processing circuit entails receiving the first and second output signals and detecting a defective one of the first and second MEMS structures from the first and second output signals by determining that the first and second output signals are uncorrelated to one another. The method further entails utilizing only the first or the second output signal from a non-defective one of the MEMS structures to produce a processed output signal when one of the MEMS structures is determined to be defective and utilizing the first and second output signals from both of the MEMS structures to produce the processed output signal when neither of the MEMS structures is defective.

A method for projecting an image comprising providing a scanning mirror having a resonance frequency which is unequal to a target operating frequency (aka “scanning frequency”) at which the mirror is to operate; and/or providing logic and an actuator e.g. motor; and/or using the scanning mirror to project at least one image, including repeatedly using the logic to measure the mirror's operating frequency and to control the actuator to apply at least one force, to the mirror, which causes the mirror's instantaneous operating frequency to equal the target operating frequency.

The disclosure provides a system, comprising: a MEMS capacitive transducer, comprising one or more first capacitive plates coupled to a first node and one or more second capacitive plates coupled to a second node; biasing circuitry coupled to the first node, operable to provide a biasing voltage to the one or more first capacitive plates; and test circuitry coupled to the second node, operable to: selectively apply one or more current sources to the second node, so as to charge and discharge the MEMS capacitive transducer and so vary a signal based on a voltage at said second node between an upper value and a lower value; determine a parameter that is indicative of a time period of the variation of the signal; and determine a capacitance of the MEMS capacitive transducer based on the parameter that is indicative of the time period.