97results about How to "Keep linear" patented technology

An AFM that combines an AFM Z position actuator and a self-actuated Z position cantilever (both operable in cyclical mode and contact mode), with appropriate nested feedback control circuitry to achieve high-speed imaging and accurate Z position measurements. A preferred embodiment of an AFM for analyzing a surface of a sample in either ambient air or fluid includes a self-actuated cantilever having a Z-positioning element integrated therewith and an oscillator that oscillates the self-actuated cantilever at a frequency generally equal to a resonant frequency of the self-actuated cantilever and at an oscillation amplitude generally equal to a setpoint value. The AFM includes a first feedback circuit nested within a second feedback circuit, wherein the first feedback circuit generates a cantilever control signal in response to vertical displacement of the self-actuated cantilever during a scanning operation, and the second feedback circuit is responsive to the cantilever control signal to generate a position control signal. A Z position actuator is also included within the second feedback circuit and is responsive to the position control signal to position the sample. In operation, preferably, the cantilever control signal alone is indicative of the topography of the sample surface. In a further embodiment, the first feedback circuit includes an active damping circuit for modifying the quality factor ("Q") of the cantilever resonance to optimize the bandwidth of the cantilever response.

A method of operating a metrology instrument includes generating relative motion between a probe and a sample at a scan frequency using an actuator. The method also includes detecting motion of the actuator using a position sensor that exhibits noise in the detected motion, and controlling the position of the actuator using a feedback loop and a feed forward algorithm. In this embodiment, the controlling step attenuates noise in the actuator position compared to noise exhibited by the position sensor over the scan bandwidth. Scan frequencies up to a third of the first scanner resonance frequency or greater than 300 Hz are possible.

An image processing apparatus that generates a combined image by combining plural image data acquired as a result of digitizing plural images acquired by shooting with different quantities of exposure, includes a weighting unit that adds weight to adjust proportion of combination of the image data, to at least one of the plural image data. The weighting unit includes a luminance data generating unit that combines data related to luminance of the plural image data and thus generates combined luminance data, and a weight deciding unit that decides the weight added to the image data in accordance with the combined luminance data generated by the luminance data generating unit.

A light wavelength converting element which can reduce an amount of light fed-back to a semiconductor laser. The light wavelength converting element converts a wavelength of a fundamental wave which enters from a first end surface side of an optical waveguide to thereby emit a converted wavelength wave from a second end surface side thereof. The second end surface is inclined with respect to the side surface of the optical waveguide. Also provided is a wavelength stabilized laser having a semiconductor laser, a device which feeds a laser beam emitted from the semiconductor laser back to the semiconductor laser, and a band-pass filter. An optical length between the semiconductor laser and the device is made to be longer than a coherent length of the semiconductor laser, thus improving linearity of a current vs. light output characteristic. Further, a light wavelength converting unit and a light wavelength converting module are provided in which, since an LD-SHG unit formed by a semiconductor laser and a light wavelength converting element is hermetically sealed in a package, the LD-SHG unit can be manufactured easily and has excellent stability over time.

The present invention relates to a digital offset phase-locked loop (DOPLL), which may have advantages of size, simplicity, performance, design portability, or any combination thereof, compared to analog-based phase-locked loops (PLLs). The DOPLL may include a digital controlled oscillator (DCO), which provides a controllable frequency output signal based on a digital control signal, a radio frequency (RF) mixer circuit, which provides a reduced-frequency feedback signal based on the controllable frequency output signal without reducing loop gain, a time-to-digital converter (TDC), which provides a digital feedback signal that is a time representation of the reduced-frequency feedback signal, and digital PLL circuitry, which provides the digital control signal based on the digital feedback signal and a digital setpoint signal.

A digitally controlled transconductance cell includes a differential transistor pair coupled to load elements (either passive or active with resistive or impedance loads) and a variable bias current source, where the transconductance or gain is digitally varied by changing the aspect ratio of the transistors and the bias current.

A scanning probe microscope method and apparatus that modifies imaging dynamics using an active drive technique to optimize the bandwidth of amplitude detection. The deflection is preferably measured by an optical detection system including a laser and a photodetector, which measures cantilever deflection by an optical beam bounce technique or another conventional technique. The detected deflection of the cantilever is subsequently demodulated to give a signal proportional to the amplitude of oscillation of the cantilever, which is thereafter used to drive the cantilever.

An object of the present invention is to provide a method for manufacturing electrodes that can effectively suppress edge-curl when metal electrodes such as bus electrodes and data electrodes are patterned mainly by a photolithography method.

In order to achieve the above object, in the manufacturing method in the present invention, an amount of undercut generated by difference in a degree of dissolution caused by developing solution is controlled, and baking is performed at a temperature such that glass in a protrusion formed at side edges becomes soft so as to touch a substrate by gravity. With such method for manufacturing, it becomes possible to make the side edges rounded whose curvature changes continuously.

A lighting controlling device of vehicle lighting equipment includes switching regulators for supplying a current to a plurality of semiconductor light sources respectively; a plurality of current driving portions, having switching elements connected to the semiconductor light sources for controlling ON/OFF of the semiconductor light sources, for current-driving the semiconductor light sources at a maximum current value or a current value smaller than the maximum current value in response to respective operating states of the switching elements; current setting portion for setting a maximum current value applied in current-driving the current driving portion or a maximum current value of currents fed from the switching regulators to the semiconductor light sources separately in plural stages in response to respective assignments; and a controlling portion for controlling the current driving portion and the current setting portion in response to a plurality of lighting modes based on communication information from an external device. The controlling portion assigns the maximum current value corresponding to each lighting mode to the current setting portion for every lighting mode, and assigns ON/OFF periods of the switching elements to the current driving portion for every lighting mode.

An electrostatic speaker capable of relaxing a restriction on the allowable amplitude of a diaphragm while maintaining the linearity of a force acting on the diaphragm. The electrostatic speaker mainly includes electrodes opposed to each other, a diaphragm, and elastic members interposed between the diaphragm and the electrodes. The elastic members have an elastic characteristic that generates a restorative force corresponding to higher order terms of an electrostatic force generated by the electrodes and acting on the diaphragm.

A slider holding a measuring tool moves along an approximately reverse U-shaped guide rail provided in parallel with a moving direction of the measuring tool without being rotated. Accordingly, a cross section of the guide rail can be enlarged without increasing the size of the entirety of a drive unit. As a result, high rigidity can be obtained while reducing the size and weight of the drive unit as compared to a conventional arrangement having two shafts. Further, linearity of the slider and the measuring tool moving along a reference surface of the guide rail can be attained with high accuracy. Further, since a pre-load means for biasing the slider toward a guide rail is provided, a position or orientation of the slider and the measuring tool can be stabilized, thus securely repeating movement of the measuring tool.

A power detector with a detection signal input connectible to a source of a radio frequency signal and a detected power level output has a differential amplifier detector circuit with an input connected to the detection signal input and an output corresponding to the detected power level output. A feedback network is connected to the input and the output of the differential amplifier detector circuit. A mirror circuit is connected to the differential amplifier detector circuit. A root mean square current corresponding to a power level of the radio frequency signal from the source is mirrored and integrated, with a direct current voltage level being generated therefrom and output to the detected power level output.

A calculating apparatus includes a finite element model creating unit that creates a finite element model of the wire structure, a setting unit that sets physical properties, restriction conditions and loads of the wire structure to the finite element model, a predictive shape calculating unit that calculates a predictive shape of the finite element model in a physically balanced condition, an outputting unit that outputs the predictive shape of the finite element model, a load calculating unit that calculates the loads which are applied to the respective joints of the finite element model, a displacing unit that displaces a predetermined control point on the finite element model. The predictive shape calculating unit calculates the predictive shape of the finite element model in which the control point is displaced, based on the loads applied to the finite element model prior to the displacement of the control point.

A random clock generator for a spread spectrum modulating device includes a random number generator for generating a plurality of random number signals according to a first square wave signal and a control signal, a reference wave generator coupled to the random number generator for generating a triangular signal and a second square wave signal according to the plurality of random number signals, and a trigger signal generator coupled to the random number generator and the reference wave generator, for generating the first square wave signal according to the second square wave signal.

A radio frequency amplifier circuit has a signal input and a signal output. A primary amplifier is connected to the signal input and the signal output. A low dropout voltage regulator is connectible to an external power supply and to the primary amplifier, and generates a set voltage to bias the primary amplifier from a variable voltage provided by the external power supply. An equivalent capacitance circuit is connected to the primary amplifier and to the low dropout voltage regulator. The equivalent capacitance circuit defines a low dropout voltage regulator output capacitance in a nano-Farad to micro-Farad range absent any passive capacitor components corresponding thereto to maintain linearity of the primary amplifier.

An oscillator circuit includes an oscillating amplifier circuit to which an oscillator element is connected, and which generates an oscillation signal, and a plurality of MOS type variable capacitance elements each having two terminals, one of which is electrically connected to the oscillating amplifier circuit, the MOS type variable capacitance elements have respective threshold voltages different from each other, a control voltage is applied to one of the terminals of each of the MOS type variable capacitance elements, and a reference voltage is applied to the other of the terminals of each of the MOS type variable capacitance elements. It is also possible for the MOS type variable capacitance elements to be different from each other in dope amount of impurities to a semiconductor layer below a gate electrode.

There is provided not only a radio frequency power amplifier using an SiGe HBT subject to a little amplification distortion, but also a communication system using the same. A conventional radio frequency power amplifier provides base bias paths of transistors Q₁ through Q_N (SiGe HBT) with bias resistors R₁₁ through R_1N having resistance values three to five times higher than those of a ballast resistor attached to each transistor's base. A coil L_B is provided in parallel with the bias resistor as a means for compensating a voltage drop due to direct current component I_DC flowing through the bias resistor. Addition of the bias resistor suppresses non-linearity of low-frequency variations in an output current. Addition of the coil compensates for voltage drop. Accordingly, the maximum linear output power can be improved. As a result, it is possible to provide the power amplifier subject to a little amplification distortion within a wide output range.