Driving device and driving method

Abstract

The invention provides a driving device and a driving method. The driving device has a driving waveform signal generator and a control element. The driving waveform signal generator provides a driving waveform signal to the optical actuator according to the waveform information provided by the control element. The sensor is used for sensing position information of an optical path offset element of the optical actuator and feeding back the position information to the control element. The control element generates updated waveform information based on the synchronization signal and the position information. The driving waveform signal generator provides an updated driving waveform signal to the optical actuator according to the updated waveform information, so that the maximum amplitude value of the driving waveform signal in the initial period is smaller than or equal to the maximum amplitude value of the driving waveform signal in the stable period, and the optical path offset element is prevented from generating excessive swing in the initial period.

Description

Technical Field

[0001] The present invention relates to a driving device and a driving method, and more particularly to a driving device and a driving method for controlling the position shift of an optical path offset element of an optical actuator. Background Art

[0002] In the technical field of projectors, known technologies can improve the resolution of projectors through pixel shift technology. However, the amount of image pixel displacement generated by the actuator during pixel shift may vary due to tolerances of electronic or mechanical components and environmental factors. When the variation affects the imaging quality, correction is required. However, the current driving device for driving the actuator to perform pixel shift is an open-loop design, which means that it has been corrected before leaving the factory and cannot monitor and compensate for the amount of image pixel displacement once it leaves the factory.

[0003] In addition, since the driving device of the known technology cannot be adjusted in real time. Therefore, the output value output from the driving device to the actuator is directly set to be equal to the target value. As a result, the actuator will generate excessive vibration at the beginning of operation, and the optical element driven in the actuator will collide with the surrounding mechanical components, resulting in noise problems.

[0004] This "Background Art" section is only used to help understand the content of the present invention. Therefore, the content disclosed in the "Background Art" section may include some known technologies that are not known to those skilled in the art. The content disclosed in the "Background Art" section does not represent that the content or the problems to be solved by one or more embodiments of the present invention have been known or recognized by those skilled in the art before the filing of the present invention application. Summary of the Invention

[0005] The present invention provides a driving device and a driving method, which can effectively improve the stability of the position shift of the optical path offset element of the optical actuator.

[0006] Other objects and advantages of the present invention can be further understood from the technical features disclosed in the present invention.

[0007] To achieve one or some or all of the above purposes or other purposes, the driving device of the present invention is used to couple to an optical actuator. The optical actuator is used to receive an image beam and has a sensor and an optical path offset element. The driving device has a driving waveform signal generator and a control element. The driving waveform signal generator is coupled to the control element and the optical actuator. Among them, the driving waveform signal generator provides a driving waveform signal to the optical actuator according to waveform information. The optical actuator drives the optical path offset element to actuate according to the driving waveform signal to offset the image beam. The sensor is used to sense the position information of the optical path offset element and feedback the position information to the control element. The control element generates updated waveform information based on the synchronization signal and the position information. The driving waveform signal generator provides an updated driving waveform signal to the optical actuator according to the updated waveform information, wherein the optical actuator, the driving waveform signal generator, and the control element form a first closed loop. Among them, the period during which the optical actuator drives the optical path offset element to actuate sequentially includes an initial period and a stable period, and the control element makes the maximum amplitude value of the driving waveform signal in the initial period less than or equal to the maximum amplitude value of the driving waveform signal in the stable period.

[0008] To achieve one or some or all of the above purposes or other purposes, the driving method of the present invention is used to drive an optical actuator by using a driving device. The optical actuator is used to receive an image beam and has a sensor and an optical path offset element. The driving device has a driving waveform signal generator and a control element. The driving method includes: according to waveform information, providing a driving waveform signal from the driving waveform signal generator to the optical actuator, receiving the driving waveform signal by the optical actuator, and driving the optical path offset element to actuate according to the driving waveform signal to offset the image beam; sensing the position information of the optical path offset element by the sensor and feedbacking the position information to the control element; generating updated waveform information in the control element based on the synchronization signal and the position information, receiving and providing the updated waveform information by the driving waveform signal generator, and providing an updated driving waveform signal to the optical actuator according to the updated waveform information, wherein the optical actuator, the driving waveform signal generator, and the control element form a first closed loop; and, wherein the period during which the optical path offset element actuates sequentially includes an initial period and a stable period, and making the maximum amplitude value of the driving waveform signal in the initial period less than or equal to the maximum amplitude value of the driving waveform signal in the stable period.

[0009] Based on the above, the driving device of the present invention provides a closed-loop system, which senses the position information of the optical path offset element through a sensor. And according to the position information, the waveform information is dynamically adjusted based on the synchronization signal, and then a dynamically adjusted driving waveform signal is generated according to the waveform information to control the actuation of the optical path offset element. Among them, the driving device of the present invention sequentially includes an initial period and a stable period during the driving of the optical path offset element. The driving device of the present invention stabilizes the stability of the position offset of the optical path offset element by making the maximum amplitude of the driving waveform signal in the initial period not greater than the maximum amplitude in the stable period. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 Schematic diagram showing a driving device according to an embodiment of the present invention.

[0011] Figure 2 Showing Figure 1 detailed schematic diagram of the driving device.

[0012] Figure 3A Schematic diagram showing the waveform information provided by the waveform information generator in an embodiment of the present invention.

[0013] Figure 3B Showing Figure 3A partial enlarged schematic diagram of the waveform information in.

[0014] Figure 4 Waveform diagram showing the operation in the initial period of an embodiment of the present invention.

[0015] Figure 5 Waveform diagram showing the operation in the initial period and the stable period of an embodiment of the present invention, and schematic diagrams showing the changes in gain values and offset values.

[0016] Figure 6 Schematic diagram showing a driving device according to another embodiment of the present invention.

[0017] Figure 7 Schematic flowchart showing a driving method according to an embodiment of the present invention.

[0018] DESCRIPTION OF REFERENCE NUMERALS:

[0019] 110, 610: Driving device

[0020] 111, 611-1, 611-2: Control element

[0021] 112, 612-1, 612-2: Driving waveform signal generator

[0022] 120, 620: Optical actuator

[0023] 121, 621: Optical path offset element

[0024] 1211, 6211: Optical elements

[0025] 1212, 6212-1, 6212-2: Magnetic elements

[0026] 122, 622-1, 622-2: Coils

[0027] 123, 623-1, 623-2: Sensors

[0028] 2111, 2112: Control circuits

[0029] 2111, 2112: Control circuits

[0030] 2113: Error information calculator

[0031] 21131: Average calculator

[0032] 2114: Waveform information generator

[0033] 2115: Clock generator

[0034] 2121: Format converter

[0035] 2122: Amplifier

[0036] CLK: Clock signal

[0037] CWFMi: Converted waveform information

[0038] D1, D2: Delayers

[0039] DC1~DC4: Amplitude values

[0040] DRV: Drive waveform signal

[0041] Er_inf: Error information

[0042] Er_L: Gain error

[0043] Er_O: Offset error

[0044] G1~G3: Gain stages

[0045] GAIN: Gain information

[0046] IB1, IB2: Buffers

[0047] O1~O3: Operational stages

[0048] OFF: Offset value

[0049] OFFi: Initial position information

[0050] OFFSET: Offset information

[0051] OFFSET: Offset information

[0052] PSF, PSF1, PSF2: Position information

[0053] RDRV: Preset waveform

[0054] REG1, REG2: Registers

[0055] RS1, RS2: Signals

[0056] s(i): Movement information

[0057] S1 to S4: Adders

[0058] S710 to S730: Steps

[0059] SB1: Subtractor

[0060] SEG: Section length information

[0061] T1 to T4: Time intervals

[0062] TGV1: First target value

[0063] TGV2: Second target value

[0064] TINI: Initial period

[0065] TSTB: Stable period

[0066] VH, VL: Peaks

[0067] Vsync: Sync signal

[0068] WFMi: Waveform information

[0069] 15: Light valve

[0070] 16: Projection lens

[0071] IB: Image beam

[0072] Wi: Weight information. Detailed implementation manners

[0073] Regarding the foregoing and other technical contents, features and effects of the present invention, they will be clearly presented in the following detailed description of a preferred embodiment with reference to the accompanying drawings. The directional terms mentioned in the following embodiments, such as: up, down, left, right, front or rear, etc., are only with reference to the directions of the accompanying drawings. Therefore, the directional terms used are for illustration and not for limiting the present invention.

[0074] Please refer to Figure 1 , Figure 1Schematic diagram of a driving device according to an embodiment of the present invention. The driving device 110 is coupled to the optical actuator 120 for driving the optical actuator 120. In this embodiment, the optical actuator 120 is used to receive an image beam IB, and the optical actuator 120 includes an optical path offset element 121, a magnetic element 1212, a coil 122, and a sensor 123. The sensor 123 is a magnetic flux sensor and is coupled to the driving device 110. The sensor 123 is, for example, a Hall sensor. The optical path offset element 121 includes an optical element 1211 and a frame (not shown) for fixing the optical element. The magnetic element 1212 is disposed on the frame for fixing the optical element 1211 to reciprocally vibrate along at least one axis together with the optical element. The optical element 1211 can be, for example, a light-transmitting element or a reflecting element for receiving the image beam IB and allowing the image beam IB to pass through or be reflected, thereby adjusting the projection position of the image beam IB by offsetting the transmission path of the image beam IB. In this embodiment, the optical element 1211 can be, for example, a light-transmitting element for receiving the image beam IB and allowing the image beam IB to pass through. The position of the optical path offset element 121 can be dynamically adjusted. The transmission path of the image beam IB can be offset corresponding to the position offset of the optical path offset element 121. The sensor 123 is used to sense the actuation of the optical path offset element 121 and feedback to the driving device 110. Thus, according to the feedback information of the sensor 123, the driving device 110 can adjust the position of the optical path offset element 121 to cause the positions of the pixels of the image to be offset, thereby improving the resolution of the projected image. It should be noted that the image beam IB is generated by converting an illumination beam (not shown) through a light valve 15. The method of converting the illumination beam into the image beam IB by the light valve 15, its detailed steps and implementation manners can be sufficiently taught, suggested, and described by the common knowledge in the technical field, so it will not be elaborated here. The light valve 15 is, for example, a reflective light modulator such as a Liquid Crystal On Silicon panel (LCoS panel), a Digital Micro-mirror Device (DMD), etc. In some embodiments, the light valve 15 can also be a transmissive liquid crystal panel, an electro-optical modulator, a magneto-optical modulator, an acousto-optical modulator (AOM), etc. The present invention does not limit the type and kind of the light valve 15.It should be noted that a light valve controller (not shown) can control the light valve 15 to modulate the image light beam IB according to a plurality of sub-display frames. Among them, the light valve controller is, for example, a Digital Light Processing (DLP). In each sub-display frame, multiple time periods respectively correspond to displaying image light beams of different colors. The sub-display frame represents a projection image that is sequentially projected. In addition, the projection lens 16 is disposed on the transmission path of the image light beam IB for projecting the image light beam IB. The projection lens 16, for example, includes a combination of one or more optical lenses with diopters, such as various combinations of non-planar lenses including double concave lenses, double convex lenses, convex-concave lenses, concave-convex lenses, plano-convex lenses, and plano-concave lenses, but is not limited thereto.

[0075] In this embodiment, the coil 122 can be disposed adjacent to the magnetic element 1212 of the optical path offset element 121. For example, the coil 122 is disposed on the base (not shown) of the optical path offset element 121. When the optical path offset element 121 is driven, the optical element 1211 and the magnetic element 1212 can reciprocally vibrate relative to the base and the coil 122. The coil 122 is further coupled to the driving device 110 and generates an induced magnetic field by receiving the driving waveform signal DRV generated by the driving device 110. The magnetic element 1212 fixed to the optical element 1211 can link the optical element 1211 according to the induced magnetic field generated by the coil 122, thereby causing the optical path offset element 121 to move in position.

[0076] On the other hand, the driving device 110 includes a control element 111 and a driving waveform signal generator 112. The control element 111 is coupled to the driving waveform signal generator 112 and the sensor 123 in the optical actuator 120. Among them, the optical actuator 120, the driving waveform signal generator 112, and the control element 111 form a closed loop.

[0077] The driving waveform signal generator 112 is coupled to the coil 122 in the optical actuator 120. The driving waveform signal generator 112 can provide the driving waveform signal DRV to the optical actuator 120 according to the waveform information WFMi. The optical actuator 120 drives the optical path offset element 121 to act according to the driving waveform signal DRV to offset the image light beam IB. The sensor 123 is used to dynamically sense the position state of the optical path offset element 121 and generate position information PSF thereby. Further, the sensor 123 feeds back the position information PSF to the control element 111 of the driving device 110.

[0078] The control element 111 receives a synchronization signal Vsync from a light valve controller (not shown). The control element 111 can generate updated waveform information WFMi based on the synchronization signal Vsync and the position information PSF. Among them, the control element 111 can calculate the difference between the initial position information of the optical path offset element 121 and the instantaneously obtained position information PSF to generate the movement information of the optical path offset element 121. The control element 111 can also perform arithmetic operations on the movement information to generate updated waveform information WFMi. The synchronization signal Vsync can be a vertical synchronization signal well known to those skilled in the art, that is, a synchronization signal corresponding to multiple sub-display frames, where a display frame includes multiple sub-display frames.

[0079] The drive waveform signal generator 112 can update the drive waveform signal DRV according to the updated waveform information WFMi instantaneously generated by the control element 111, transmit the updated drive waveform signal DRV to the optical actuator 120, and dynamically adjust the position state of the optical path offset element 121 of the optical actuator 120 by providing the instantaneously updated drive waveform signal DRV.

[0080] Here, please note that in this embodiment, the period during which the optical actuator 120 drives the optical path offset element 121 to act includes an initial period and a stable period in sequence. The control element 111 makes the maximum amplitude value of the drive waveform signal DRV in the initial period less than or equal to the maximum amplitude value of the drive waveform signal DRV in the stable period. That is to say, the driving device 110 forms a closed-loop control mechanism with the optical actuator 120, and through the closed-loop control mechanism, it can make the maximum amplitude of the corresponding drive waveform signal DRV in the initial period when the optical path offset element 121 acts less than or equal to the maximum amplitude of the corresponding drive waveform signal DRV in the stable period when the optical path offset element 121 acts. Among them, the initial period and the stable period when the optical path offset element 121 acts are defined in chronological order. In this way, the swing amount of the optical path offset element 121 can be effectively controlled, and excessive oscillation will not occur in the initial state, avoiding collisions with surrounding components and generating noise.

[0081] Please refer to Figure 2 , Figure 2 the detailed schematic diagram of the driving device shown in Figure 1 . It can be understood that Figure 2 the component names defined in Figure 1Components with the same defined names represent the same components, so they will not be elaborated here. The driving device 110 is coupled to the optical actuator 120. In this embodiment, the optical actuator 120 includes an optical path offset element 121, a coil 122, a magnetic element 1212, and a sensor 123. The optical path offset element 121 includes an optical element 1211. The driving device 110 includes a control element 111 and a driving waveform signal generator 112.

[0082] The driving waveform signal generator 112 includes a signal format converter 2121 and an amplifier 2122. The signal format converter 2121 is coupled to the control element 111 and is used to convert the signal format of the waveform information WFMi to generate a converted waveform information CWFMi. In this embodiment, the signal format converter 2121 can be a digital-to-analog conversion circuit (DAC). Among them, the waveform information WFMi is a digital signal, and the converted waveform information CWFMi is an analog signal. The amplifier 2122 is coupled to the output end of the signal format converter 2121. The amplifier 2122 receives the converted waveform information CWFMi and generates a driving waveform signal DRV by amplifying the converted waveform information CWFMi, and transmits the driving waveform signal DRV to the optical actuator 120 to drive the optical path offset element 121.

[0083] Please continue to refer to Figure 2, the control element 111 includes control circuits 2111, 2112, an error information calculator 2113, a waveform information generator 2114, and a clock generator 2115. Among them, the error information calculator 2113 receives the position information PSF from the sensor 123 and calculates an error information Er_inf. In addition, the control circuits 2111, 2112 are respectively coupled to the error information calculator 2113 to receive the error information Er_inf and perform a control algorithm on the error information Er_inf to generate an offset information OFFSET and a gain information GAIN corresponding to the waveform information WFMi. The waveform information generator 2114 is coupled to the control circuits 2111, 2112 to generate updated waveform information WFMi according to the offset information OFFSET and the gain information GAIN. That is to say, the control element 111 can perform the above control algorithm on the error information Er_inf to generate updated waveform information WFMi, and convert the updated waveform information WFMi into an updated drive waveform signal DRV by driving the waveform signal generator 112. The waveform signal generator 112 transmits the updated drive waveform signal DRV to the optical actuator 120 to drive the optical path offset element 121. Thus, the control element 111 makes the maximum amplitude value of the drive waveform signal DRV during the initial period less than or equal to the maximum amplitude value of the drive waveform signal DRV during the stable period.

[0084] Regarding the waveform information generator 2114, please refer to Figure 2 and Figure 3A , where Figure 3A shows a schematic diagram of the waveform information provided by the waveform information generator in an embodiment of the present invention. Figure 3B shows Figure 3A a partial enlarged schematic diagram of the waveform information in. In Figure 3A , the waveform information WFMi provided by the waveform information generator 2114 can be a discrete signal. The waveform information WFMi represents the desired waveform of the drive waveform signal DRV in a display frame period (or frame period).

[0085] In addition, in Figure 3BAmong them, by locally magnifying the region Z1 of the waveform information WFMi, the waveform information WFMi provided by the waveform information generator 2114 can correspond to a plurality of time intervals T1, T2, T3, T4, …, and has a plurality of amplitude values DC1, DC2, DC3, DC4, … respectively corresponding to the plurality of time intervals T1, T2, T3, T4, …. In this embodiment, the amplitude values DC1, DC2, DC3, DC4, … can be respectively a plurality of digital values. The waveform information generator 2114 can generate the waveform information WFMi by generating digital codes respectively corresponding to the plurality of amplitude values DC1, DC2, DC3, DC4, … of the plurality of time intervals T1, T2, T3, T4, ….

[0086] Please refer back to Figure 2 , the waveform information generator 2114 can receive the offset information OFFSET, the gain information GAIN, and the segment length information SEG to generate the waveform information WFMi. The waveform information generator 2114 can set the time lengths of the respective time intervals T1, T2, T3, T4, … according to the segment length information SEG; set the magnitudes of the respective amplitude values DC1, DC2, DC3, DC4, … according to the gain information GAIN; and set the zero point of the waveform information WFMi according to the offset information OFFSET. Moreover, the waveform information generator 2114 can control the time lengths of the offset information OFFSET and the gain information GAIN in each time segment in the waveform information WFMi based on the segment length information SEG and the received clock signal CLK.

[0087] Among them, the segment length information SEG can be pre-stored in the register REG1 and provided by the register REG1. Details regarding the generation of the offset information OFFSET and the gain information GAIN will be described in detail in the subsequent embodiments.

[0088] The error information calculator 2113 includes buffers IB1, IB2, adders S3, S4, and an average calculator 21131. Among them, buffer IB2 receives the initial position information OFFi, and buffer IB2 has a gain value of -1 to generate the product of the initial position information OFFi and -1. Adder S4 receives the output signal of buffer IB2 and the position information PSF from sensor 123. Adder S4 is used to calculate the difference between the position information PSF and the initial position information OFFi, and thereby generate the movement information s(i) of the optical path offset element 121. The average calculator 21131 is coupled to adder S4 and receives the movement information s(i) and the weight information Wi. The average calculator 21131 performs a weighting operation on a part of the movement information s(i) according to the weight information Wi, and generates the first peak value and the second peak value of a part of the movement information s(i) by calculating the weighted average value of a part of the movement information s(i). Further, the average calculator 21131 can calculate the average value of the first peak value and the second peak value to obtain an offset value OFF of the movement information s(i).

[0089] For the calculation details of the first peak value and the second peak value, please refer to Figure 2 and Figure 4 where Figure 4 shows the operation waveform diagram during the initial period of the embodiment of the present invention. It should be noted that Figure 4 the operation waveform diagram during the initial period of Figure 2 refers to the waveform diagram corresponding to the operation process of the drive circuit 110 of

[0090] During Figure 4 the movement information s(i) can be generated by subtracting the initial position information OFFi from the position information PSF. The average calculator 21131 can also perform a filtering operation on the movement information s(i), obtain the first peak value VH by calculating the average value of the positive half-wave of the movement information s(i), and obtain the second peak value VL by calculating the average value of the negative half-wave of the movement information s(i). The average calculator 21131 can also calculate the average value of the first peak value VH and the second peak value VL to generate the offset value of the movement information s(i).

[0091] The error information calculator 2113 receives target information TGi (the target information TGi may include the aforementioned first target value TGV1 and the target offset value), and subtracts the offset value OFF from the target information TGi through a buffer IB1 with a gain of -1 and an adder S3 to generate error information Er_inf. Among them, the error information calculator 2113 can generate the error information Er_inf by calculating the difference between the first target value TGV1 and the first peak value VH and the difference between the target offset value and the offset value OFF. In this embodiment, the error information Er_inf includes a gain error Er_L and an offset error Er_O. The gain error Er_L can be generated according to the difference between the first target value TGV1 and the first peak value VH, and the offset error Er_O can be generated according to the difference between the target offset value and the offset value OFF.

[0092] It is worth mentioning that the target information TGi, the weight information Wi, and the initial position information OFFi can be pre-stored in the register REG2.

[0093] Regarding the details of weight calculation, by appropriately setting the value of the weight information Wi, the timing window for the averaging calculator 21131 to perform filtering operations on the movement information s(i) can be set. For example, the value of the weight information Wi outside the time window can be set to 0, and the value of the weight information Wi within the time window can be set to a real number greater than 0. Further, when the averaging calculator 21131 calculates the first peak value VH, an appropriate time window can be set for the positive half-wave of the movement information s(i). For example, the time window includes n1 time points, and n1 is any positive integer greater than 1. The averaging calculator 21131 can calculate the first peak value VH = ∑ n1 s(i) × wi, where, ∑ n1 wi = 1.

[0094] On the other hand, when the averaging calculator 21131 calculates the second peak value VL, an appropriate time window can be set for the negative half-wave of the movement information s(i). For example, the time window includes n2 time points, and n2 is any positive integer greater than 1. The averaging calculator 21131 can calculate the second peak value VL = ∑ n2 s(i) × wi, where, ∑ n2 wi = 1.

[0095] Please continue to refer to Figure 2, the control circuit 2111 and the control circuit 2112 can be similar circuit architectures, but this is not a limitation. In some embodiments, the control circuit 2111 is substantially the first control circuit 2111, and the control circuit 2112 is substantially the second control circuit 2112. That is to say, the control circuits 2111 and 2112 can substantially include the first control circuit 2111 and the second control circuit 2112. The gain error Er_L and the offset error Er_O are respectively transmitted to the first control circuit 2111 and the second control circuit 2112. In this embodiment, the first control circuit 2111 and the second control circuit 2112 can be proportional-integral-derivative control circuits (PID controlling circuits). Taking the first control circuit 2111 as an example, the first control circuit 2111 can have gain stages G1 to G3 and operation stages O1 to O3. The gain stages G1 to G3 are respectively coupled to the operation stages O1 to O3. The gain stages G1 to G3 respectively provide gain values Kp, Ki, and Kd to modulate the gain error Er_L. The modulated gain error Er_L is transmitted to the operation stages O1 to O3 to respectively perform proportional operation (e(n)), integral operation and differential operation (e(n) - e(n - 1)), and then through the adder S1 to sum the operation results to generate the signal RS1. Among them, e(n), e(n - 1), and e(i) are the gain error Er_L. The control algorithm provided by the above first control circuit 2111 is only an example, not a limitation.

[0096] Outside the first control circuit 2111, the signal RS1 cooperates with the accumulative subtraction operation of the delay device D1 and the subtractor SB1 to generate the gain information GAIN. That is to say, the first control circuit 2111 receives the gain error Er_L in the error information Er_inf and executes a control algorithm for the gain error Er_L to generate the updated gain information GAIN corresponding to the waveform information WFMi.

[0097] In addition, the second control circuit 2112 can perform operations according to the offset error Er_O to generate the signal RS2. Outside the second control circuit 2112, the signal RS2 cooperates with the accumulative addition operation of the delay device D2 and the adder S2 to generate the offset information OFFSET. That is to say, the second control circuit 2112 can receive the offset error Er_O in the error information Er_inf and execute a control algorithm for the offset error Er_O to generate the updated offset information OFFSET corresponding to the waveform information WFMi.

[0098] It is worth mentioning that, in other embodiments of the present invention, each of the control circuits 2111 and 2112 may also include only at least any one or any two of a proportional control circuit, an integral control circuit, and a derivative control circuit. Alternatively, each of the control circuits 2111 and 2112 may also be a robust control circuit, an adaptive control circuit, a fuzzy theory control circuit, a genetic algorithm control circuit, or a neural network control circuit, but this is not intended to limit the present invention.

[0099] On the other hand, the clock generator 2115 receives the synchronization signal Vsync and generates a clock signal CLK according to the synchronization signal Vsync. The synchronization signal Vsync is used to indicate the start of each display frame period. The clock generator 2115 also provides the generated clock signal CLK to the waveform information generator 2114 and the error information calculator 2113 as the operating clocks of the waveform information generator 2114 and the error information calculator 2113.

[0100] Incidentally, the clock signal CLK may be a subframe clock signal. In an embodiment of the present invention, a display frame may be divided into multiple sub-display frames to improve the resolution of the projected projection image. Among them, a display frame may be divided into two sub-display frames, for example, or divided into four sub-display frames, but this is not limited thereto. Different sub-display frame periods may respectively correspond to image beams of different display colors.

[0101] Please refer to the following Figure 5 , Figure 5 to illustrate the operation waveform diagrams of the initial period and the stable period of the embodiment of the present invention and the schematic diagrams of the changes in the gain value and the offset value. It should be noted that Figure 5 the operation waveform diagrams of the initial period and the stable period refer to Figure 2 the corresponding waveform diagrams during the operation of the driving circuit 110 of

[0102] It is worth mentioning that during the initial period TINI, the maximum amplitude of the driving waveform signal DRV can be less than or equal to the maximum amplitude of the driving waveform signal DRV during the stable period TSTB. That is to say, through the closed-loop control mechanism of the embodiments of the present invention, it is possible to effectively avoid excessive surges in the driving waveform signal DRV during the initial period TINI, and to avoid unstable vibrations of the optical path offset element 121.

[0103] Please refer to the following Figure 6 , Figure 6 for a schematic diagram of a driving device according to another embodiment of the present invention. It can be understood that Figure 6 the component names defined by Figure 1 and those with the same component names defined by Figure 1 represent the same components, so they will not be described in detail here. The driving device 610 is coupled to the optical actuator 620. Compared with

[0104] the driving device 610 further includes another driving waveform signal generator 612-1 and another control element 611-1. The optical actuator 620 has another sensor 623-1. The optical actuator 620, the another driving waveform signal sensor 612-1, and the another control element 611-1 form a second closed loop. That is to say, the driving device 610 of this embodiment includes control elements 611-1, 611-2, driving waveform signal generators 612-1, and 612-2. The optical actuator 620 includes an optical path offset element 621, coils 622-1, 622-2, magnetic elements 6212-1, 6212-2, and sensors 623-1, 623-2. The optical path offset element 621 includes an optical element 6211. In this embodiment, the optical path offset element 621 can reciprocally vibrate about the first axis and / or reciprocally vibrate about the second axis. Among them, the coil 622-1 can provide an induced magnetic field to induce the magnetic element 6212-1 to cause the optical path offset element 621 to reciprocally vibrate about the first axis, and the coil 622-2 can provide an induced magnetic field to induce the magnetic element 6212-2 to cause the optical path offset element 621 to reciprocally vibrate about the second axis.

[0104] The sensors 623-1, 623-2 are respectively used to sense the position information PSF1, PSF2 of the optical path offset element 621 corresponding to the vibration about the first axis and the vibration about the second axis. The control element 611-2, the driving waveform signal generator 612-2 are similar to Figure 1 the optical actuator 620 and can form a first closed loop. The control element 611-1, the driving waveform signal generator 612-1 and the optical actuator 620 can form a second closed loop. Among them, the above-mentioned first axis and the second axis are not the same. For example, the first axis can be the X axis, and the second axis can be the Y axis.

[0105] The control elements 611-1 and 611-2 can operate based on the synchronization signal Vsync. The circuit details and operating principles of the above-mentioned first and second closed loops are the same as those of the closed-loop control mechanism formed by the driving device 110 in the Figure 2 embodiment, so they will not be elaborated here.

[0106] It is worth mentioning that the driving device in the embodiment of the present invention can also be expanded to have a larger number of closed loops, so as to provide a control mechanism for multiple optical actuators.

[0107] Please refer to the following Figure 7 , Figure 7 for a schematic flowchart showing the driving method according to an embodiment of the present invention. The driving method is used to drive an optical actuator by a driving device. The optical actuator is used to receive an image beam and has a sensor and an optical path offset element. The driving device has a driving waveform signal generator and a control element. In step S710, according to the waveform information, the driving waveform signal generator provides a driving waveform signal to the optical actuator; the optical actuator receives the driving waveform signal and drives the optical path offset element of the optical actuator to actuate according to the driving waveform signal to offset the image beam. In step S720, the sensor senses the position information of the optical path offset element and feeds back the position information to the control element. In step S730, based on the synchronization signal and the position information, the control element generates updated waveform information; the driving waveform signal generator receives and provides the updated waveform information, and provides an updated driving waveform signal to the optical actuator according to the updated waveform information. Among them, the optical actuator, the driving waveform signal generator, and the control element form a first closed loop, so that the maximum amplitude value of the driving waveform signal during an initial period is less than or equal to the maximum amplitude value of the driving waveform signal during a stable period.

[0108] Regarding the operation details of the above steps S710 to S730, detailed descriptions have been given in the foregoing embodiments, so they will not be elaborated here.

[0109] In summary, the driving device of the present invention forms a closed loop with the sensor on the optical actuator, and controls the swinging state of the optical path offset element through the closed-loop control mechanism. By making the maximum amplitude value of the driving waveform signal during the initial period when the optical path offset element is actuated less than or equal to the maximum amplitude value of the driving waveform signal during the stable period when the optical path offset element is actuated, it is possible to effectively prevent the optical path offset element from swinging too much and reduce the image display performance.

[0110] The above are only the preferred embodiments of the present invention, and should not be used to limit the scope of the present invention. That is, all simple equivalent changes and modifications made according to the claims of the present invention and the content of the invention still fall within the scope covered by the patent of the present invention. In addition, any embodiment or claim of the present invention does not have to achieve all the purposes, advantages or features disclosed in the present invention. In addition, the abstract and title (invention name) are only used to assist in the retrieval of patent documents and are not used to limit the scope of the rights of the present invention. In addition, the terms "first", "second", etc. mentioned in this specification or claims are only used to name the elements or distinguish different embodiments or scopes, and are not used to limit the upper or lower limits of the number of elements.

Claims

1. A driving device, characterized in that, The driving device is used to couple to an optical actuator, which is used to receive an image beam and has a sensor and an optical path offset element. The driving device has a driving waveform signal generator and a control element. The driving waveform signal generator is coupled to the control element and the optical actuator. Among them, the driving waveform signal generator provides a driving waveform signal to the optical actuator according to waveform information, and the optical actuator drives the optical path offset element to actuate according to the driving waveform signal to offset the image beam; the sensor is used to sense the position information of the optical path offset element and feedback the position information to the control element; and the control element generates updated waveform information based on a synchronization signal and the position information. The driving waveform signal generator provides updated driving waveform signal to the optical actuator according to the updated waveform information. Among them, the optical actuator, the driving waveform signal generator and the control element form a first closed loop; wherein the period during which the optical actuator drives the optical path offset element to actuate sequentially includes an initial period and a stable period, and the control element makes the maximum amplitude value of the driving waveform signal in the initial period less than or equal to the maximum amplitude value of the driving waveform signal in the stable period.

2. The drive device according to claim 1, characterized in that, The control element calculates the difference between the position information and the initial position information to obtain the movement information of the optical path offset element of the optical actuator. The control element calculates the weighted average value of a part of the movement information according to weight information to obtain the first peak value and the second peak value corresponding to the part of the movement information. The control element also calculates the average value of the first peak value and the second peak value to generate the offset value of the movement information.

3. The drive device according to claim 2, characterized in that The control element calculates the difference between the first target value and the first peak value, and the difference between the target offset value and the offset value to generate error information.

4. The drive device according to claim 3, characterized in that, The target offset value is equal to the average value of the first target value and the second target value.

5. The drive device according to claim 3, characterized in that, The control element executes a control algorithm for the error information to generate updated waveform information.

6. The drive device according to claim 1, characterized in that The control element includes: an error information calculator, which receives the position information from the sensor and calculates error information; a control circuit, which is coupled to the error information calculator, receives the error information and executes a control algorithm for the error information to generate offset information and gain information corresponding to the waveform information; and a waveform information generator, which is coupled to the control circuit and is used to generate updated waveform information according to the offset information and the gain information.

7. The drive device according to claim 6, characterized in that, The error information calculator includes an average calculator. The error information calculator is used to: calculate the difference between the position information and the initial position information to obtain the movement information of the optical path offset element of the optical actuator; use the average calculator to calculate the weighted average value of a part of the movement information according to weight information to obtain the first peak value and the second peak value of a part of the movement information; Calculate the average value of the first peak and the second peak using the average calculator to generate an offset value of the mobile information; And Calculate the difference between the first target value and the first peak, and the difference between the target offset value and the offset value to generate the error information.

8. The drive device according to claim 6, characterized in that The control circuit includes at least one of a proportional control circuit, an integral control circuit, and a derivative control circuit.

9. The drive device according to claim 6, characterized in that, The control circuit is a robust control circuit, an adaptive control circuit, a fuzzy theory control circuit, a genetic algorithm control circuit, or a neural network control circuit.

10. The drive device according to claim 6, characterized in that The control circuit includes: A first control circuit that receives the gain error in the error information and executes the control algorithm for the gain error to generate the updated gain information corresponding to the waveform information; and A second control circuit that receives the offset error in the error information and executes the control algorithm for the offset error to generate the updated offset information corresponding to the waveform information.

11. The drive device according to claim 6, characterized in that, The control element further includes: A clock generator that receives the synchronization signal and provides a clock signal to the error information calculator and the waveform information generator according to the synchronization signal.

12. The drive device according to claim 11, characterized in that, The control element further includes a register. The register is coupled to the waveform information generator. The waveform information generator receives the segment length information from the register. The waveform information generator controls the time lengths of the offset information and the gain information in each time segment of the waveform information based on the segment length information and the clock signal.

13. The drive device according to claim 1, characterized in that, The drive waveform signal generator includes: A signal format converter that is coupled to the control element and converts the signal format of the waveform information to generate the converted waveform information; and An amplifier that is coupled to the signal format converter and amplifies the converted waveform information to generate the drive waveform signal.

14. The drive device according to claim 13, characterized in that, The waveform information is a digital signal, and the converted waveform information is an analog signal.

15. The drive device according to claim 1, characterized in that, The sensor is a magnetic flux sensor.

16. The drive device according to claim 1, characterized in that, The drive device further includes another drive waveform signal generator and another control element. The optical actuator has another sensor. The optical actuator, the another drive waveform signal generator, and the another control element form a second closed loop. Wherein the optical actuator drives the optical path offset element to swing in the first axial direction according to the drive waveform signal from the first closed loop, and drives the optical path offset element to swing in the second axial direction according to the drive waveform signal from the second closed loop. The first axial direction is different from the second axial direction.

17. A driving method, characterized in that, The drive method is used to drive an optical actuator using a drive device. The optical actuator is used to receive an image beam and has a sensor and an optical path offset element. The drive device has a drive waveform signal generator and a control element. The drive method includes: According to the waveform information, provide a drive waveform signal from the drive waveform signal generator to the optical actuator; The optical actuator receives the drive waveform signal and drives the optical path offset element to actuate according to the drive waveform signal to offset the image beam; The sensor senses the position information of the optical path offset element and feeds back the position information to the control element; Based on the synchronization signal and the position information, updated waveform information is generated in the control element; The updated waveform information is received by the drive waveform signal generator, and an updated drive waveform signal is provided to the optical actuator according to the updated waveform information, wherein the optical actuator, the drive waveform signal generator, and the control element form a first closed loop; and During the operation of the optical path offset element, the period sequentially includes an initial period and a stable period, such that the maximum amplitude value of the drive waveform signal in the initial period is less than or equal to the maximum amplitude value of the drive waveform signal in the stable period.

18. The driving method according to claim 17, characterized in that, The driving method further includes: Calculating, in the control element, the difference between the position information and the initial position information to obtain the movement information of the optical path offset element of the optical actuator; Calculating, in the control element, the weighted average of a part of the movement information according to the weight information to obtain a first peak value and a second peak value corresponding to the part of the movement information; and Calculating, in the control element, the average value of the first peak value and the second peak value to generate an offset value of the movement information.

19. The driving method according to claim 18, characterized in that, The driving method further includes: Calculating, in the control element, the difference between the first target value and the first peak value and the difference between the target offset value and the offset value to generate error information.

20. The driving method according to claim 19, wherein The target offset value is equal to the average value of the first target value and the second target value.

21. The driving method according to claim 19, characterized in that, The driving method further includes: performing a control algorithm in the control element for the error information to generate the waveform information.

22. The driving method according to claim 17, characterized in that, The driving method further includes: Generating a clock signal in the control element according to the synchronization signal; and Based on the segment length information and the clock signal, controlling, in the control element, the time lengths of the offset information and the gain information in each time segment in the waveform information.

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