# US 10,871,645 B2 · Phase control device and method for multi-resonance system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,871,645 B2 - Document ID: US10871645B2 - Status: Granted - Kind: B2 - Application number: 15/959,696 - Filed: 2018-04-23 - Published: 2019-10-24 - Granted: 2020-12-22 - Earliest claimed: 2018-04-23 - Assignees: Microsoft Technology Licensing, LLC - Applicants: Microsoft Technology Licensing, LLC - Inventors: Chuan Pu; Wenjun Liao - Web page: https://patentgrep.com/patent/US10871645B2 ## CPC - G02B 26/0858: {the reflecting means being moved or deformed by piezoelectric means} - H03L 7/00: Automatic control of frequency or phase; Synchronisation - G02B 26/101: {with both horizontal and vertical deflecting means, e.g. raster or XY scanners (colour television using laser beams scanning a display screen H04N9/3129)} - H03L 7/0802: {the loop being adapted for reducing power consumption (H03L7/14 takes precedence)} - H03L 7/093: using special filtering or amplification characteristics in the loop (H03L7/087 - H03L7/091 take precedence) - H03L 7/099: concerning mainly the controlled oscillator of the loop - H02N 2/02: producing linear motion, e.g. actuators; Linear positioners {; Linear motors} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - H03L: AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES (generation of oscillations H03B) - H02N: ELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR ## Abstract A resonance system is disclosed, which includes a first resonance device configured to receive a drive signal and generate an output signal, a second resonance device configured to receive a control signal and generate the drive signal based on the received control signal, and a controller configured to generate the control signal based on the output signal such that a phase difference between the control signal applied to the second resonance device and the output signal of the first resonance device corresponds to a predetermined phase shift value. ## Claims ### Claim 1 A resonance system comprising: a first resonance device configured to receive a drive signal and generate an output signal; a second resonance device configured to receive a control signal and generate the drive signal based on the received control signal; and a controller configured to generate the control signal based on the output signal such that a phase difference between the control signal applied to the second resonance device and the output signal of the first resonance device corresponds to a predetermined phase shift value. ### Claim 2 (depends on 1) The resonance system of claim 1, wherein the predetermined phase shift value is based on a first phase shift caused by the first resonance device and a second phase shift caused by the second resonance device. ### Claim 3 (depends on 1) The resonance system of claim 1, wherein the predetermined phase shift value is not 90°. ### Claim 4 (depends on 1) The resonance system of claim 1, wherein the first resonance device is a micro electro mechanical system (MEMS) scanner comprising a MEMS mirror configured to oscillated based on the drive signal. ### Claim 5 (depends on 1) The resonance system of claim 1, wherein the first resonance device comprises a sensor configured to detect an oscillation of the first resonance device and generate the output signal including phase information associated with the first resonance device. ### Claim 6 (depends on 5) The resonance system of claim 5, wherein the controller comprises: a phase-locked loop (PLL) configured to output the control signal; and a processor configured to generate a PLL control signal, wherein the PLL control signal is configured to adjust a phase of the control signal such that the phase difference between the control signal and the output signal of the first resonance device corresponds to the predetermined phase shift value. ### Claim 7 (depends on 6) The resonance system of claim 6, wherein the processor is configured to control the PLL using the PLL control signal to lock the phase of the control signal when the phase difference corresponds to the predetermined phase shift value. ### Claim 8 (depends on 6) The resonance system of claim 6, wherein the PLL comprises: a voltage-controlled oscillator (VCO) configured to output the control signal; a phase detector configured to receive the control signal output from the VCO and the output signal; and a filter coupled between the phase detector and the VCO, wherein the processor is configured to receive the control signal output from the PLL and the output signal to detect the phase difference. ### Claim 9 (depends on 8) The resonance system of claim 8, further comprising a data storage unit configured to store the predetermined phase shift value, wherein the processor is configured to compare the phase difference to the predetermined phase shift value and output the PLL control signal based on a result of the comparison between the phase difference and the predetermine phase shift value. ### Claim 10 A controller for a resonance system, the controller comprising: a phase-locked loop (PLL) configured to output a control signal; and a processor configured to control the PLL based on the control signal output from the PLL and an output signal received from a first resonance device, wherein the first resonance device is driven by a drive signal generated by a second resonance device based on the control signal, wherein the processor is configured to control the PLL to adjust a phase difference between the control signal and the output signal of the first resonance device to correspond to a predetermined phase shift value. ### Claim 11 (depends on 10) The controller of claim 10, wherein the predetermined phase shift value is based on a first phase shift caused by the first resonance device and a second phase shift caused by the second resonance device. ### Claim 12 (depends on 10) The controller of claim 10, wherein the processor controls the PLL to adjust a phase of the control signal such that the phase difference corresponds to the predetermined phase shift value. ### Claim 13 (depends on 12) The controller of claim 12, wherein the processor controls the PLL to lock the phase of the control signal when the phase difference corresponds to the predetermined phase shift value. ### Claim 14 (depends on 10) The controller of claim 10, wherein the PLL comprises: a voltage-controlled oscillator (VCO) configured to output the control signal; a phase detector configured to receive the control signal output from the VCO and the output signal; and a filter coupled between the phase detector and the VCO. ### Claim 15 (depends on 10) The controller of claim 10, further comprising a data storage unit configured to store the predetermined phase shift value, wherein the processor compares the phase difference to the predetermined phase shift value. ### Claim 16 (depends on 15) The controller of claim 15, wherein: the processor is configured to control the PLL by generating a PLL control signal, and the PLL control signal is generated based on a result of a comparison between the phase different and the predetermined phase shift value. ### Claim 17 A method of controlling a resonance system, the method comprising: receiving an output signal from a first resonance device, the output signal including oscillation information of the first resonance device; generating a control signal based on the received output signal; supplying the generated control signal to a second resonance device configured to generate a drive signal for driving the first resonance device based on the control signal; determining a phase difference between the control signal and the output signal of the first resonance device; and adjusting the phase difference to correspond to a predetermined phase shift. ### Claim 18 (depends on 17) The method of claim 17, wherein the adjusting the phase difference includes adjusting a phase of the control signal such that the phase difference corresponds to the predetermined phase shift value. ### Claim 19 (depends on 18) The method of claim 18, further comprising locking the phase difference if the phase difference corresponds to the predetermined phase value. ### Claim 20 (depends on 17) The method of claim 17, further comprising: performing frequency scanning to obtain a frequency response of the resonance system; determining a resonance frequency and a phase shift range of the resonance system based on a system transfer function of the resonance system; selecting an initial phase shift value from the phase shift range; determining whether the initial phase shift value meets a control requirement; adjusting the initial phase shift value if the initial phase shift value does not meet the control requirement; and determining the predetermined phase shift value based on the initial phase shift value or the adjusted phase shift value that meets the control requirement.