74results about How to "Reduce phase distortion" patented technology

A method of delivering ultrasound signals using shear waves includes applying a portion of at least a first ultrasound beam to a subject at at least a first incident angle relative to the surface of the subject to induce shear waves in the subject, energy in the shear waves forming a substantial part of energy of first ultrasound waves at a desired region in the subject at a therapeutic level.

A power amplifier controller circuit controls a power amplifier based upon an amplitude correction signal indicating the amplitude difference between the amplitude of the input signal and an attenuated amplitude of the output signal. The power amplifier controller circuit comprises an amplitude control loop and a phase control loop. The amplitude control loop adjusts the supply voltage to the power amplifier based upon the amplitude correction signal. The RF power amplifier system may reduce the corrective action of the amplitude loop during periods of relatively rapid changes in amplitude, and thus distortion can be further reduced.

The invention discloses a moulding method of a variable-density broadband wave-transparent quartz composite ceramic antenna housing body. The method comprises the following steps: according to dimension and quality request of the housing body, integrally weaving an outer material and an inner material to obtain an inner and outer housing body fabric; putting the housing body fabric in water to be cooked and soaking in acid liquor; then, putting the housing body fabric in an utensil filled with a silica sol for dipping and compounding; and finally machining a housing body blank to a required dimension to obtain the antenna housing body. According to the moulding method disclosed by the invention, the outer layer of the housing body fabric is woven by quartz fiber yarns, so that the volume percentage of the quartz fiber yarns is 40-45% while the inner layer of the housing body fabric is woven by hollow quartz fiber yarns, so that the volume percentage of the hollow quartz fiber yarns is 25-30%, therefore, the fiber volume percentages of the inner and outer layers of the housing body fabric are different. Meanwhile, the inner and outer layers are integrally attached and woven, the layering problem is avoided, and the housing body has relatively good structural strength is powerfully guaranteed as a result of relatively good strength of a reinforcement.

An adder unit (60e) reads a desired CGH pattern from a pattern memory unit (60a) and a phase distortion correction pattern from a distortion-correction pattern memory unit (60d) and adds both patterns together to generate a phase distortion corrected pattern. A control unit (60g) controls a phase modulation module (40) in accordance with the phase distortion corrected pattern. Accordingly, phase-modulated light based on the desired phase pattern can be generated precisely, easily and quickly.