Laser projection equipment

Abstract

The embodiment of the invention belongs to the display technology, and provides laser projection equipment which comprises a light source, a light machine and a lens. The light machine comprises a light uniformizing device, the light uniformizing device is arranged on a light path of the illumination light beam and located between the light source and the lens, and the light uniformizing device comprises a first coil, a second coil and a light uniformizing piece; the ray machine further comprises a driving module which is connected with the first coil and the second coil and is used for sending a first power-on signal to the first coil to enable the first coil to be powered on and sending a second power-on signal to the second coil to enable the second coil to be powered on. The dodging piece moves under the magnetic force generated after the first coil and / or the second coil are / is powered on. The phase difference between the first power-on signal and the second power-on signal is a quarter period. The laser projection equipment provided by the invention can be used for dodging and eliminating speckles.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to display technology. In particular, embodiments of the present application relate to a laser projection device. BACKGROUND

[0002] Laser projection devices using laser light sources have better unidirectionality, narrower wavelength range, and are prone to interference, which can cause granular speckle spots on the projected image. Speckle can affect the quality of the projected image and reduce the viewing experience. Therefore, in the projection device, a light uniformization device is needed to eliminate speckle and uniformize light, thereby improving the projection quality.

[0003] Some laser projection devices use a moving diffusion wheel as a light uniformization device to eliminate speckle and uniformize light. The diffusion wheel is equipped with a motor to drive a circular diffusion sheet to rotate at high speed. However, due to the size of the diffusion wheel, the light uniformization device has a large volume, which makes it difficult to achieve the ideal size of the projection device. Therefore, some other light uniformization devices introduce a smaller light uniformization device, such as a movable diffusion sheet, to replace the diffusion wheel. Although this can reduce the volume of the light uniformization device, how to drive the light uniformization device to operate to achieve light uniformization and speckle elimination remains a problem to be solved. SUMMARY

[0004] Embodiments of the present application provide a laser projection device that can efficiently drive a light uniformization device to operate and achieve light uniformization and speckle elimination.

[0005] In a first aspect, embodiments of the present application provide a laser projection device. The laser projection device includes a light source configured to provide an illumination light beam; an optical engine disposed on an optical path of the illumination light beam and configured to adjust the illumination light beam to obtain a projection light beam; and a lens configured to image the projection light beam. The optical engine includes a light uniformization device disposed on the optical path of the illumination light beam and located between the light source and the lens. The light uniformization device includes a first coil, a second coil, and a light uniformization member. The optical engine further includes a driving module connected to the first coil and connected to the second coil. The driving module is configured to send a first energizing signal to the first coil to energize the first coil, and send a second energizing signal to the second coil to energize the second coil. The light uniformization member moves under the magnetic force generated by the energized first coil and / or the energized second coil. The phase difference between the first energizing signal and the second energizing signal is one-quarter of a period.

[0006] The laser projection device provided in the application controls the phase difference between the first current signal and the second current signal to be one quarter of a period by applying the first current signal and the second current signal to the first coil and the second coil respectively, so that the first coil and the second coil are energized under the drive of the first current signal and the second current signal, and the light uniformizing member is operated, thereby efficiently performing light uniformization and speckle elimination and improving the quality of the image projected by the laser projection device.

[0007] In some embodiments of the application, the first coil comprises a first positive terminal and a first negative terminal, the first positive terminal receives the first current signal in the first half of the period, and the first negative terminal receives the first current signal in the second half of the period; the second coil comprises a second positive terminal and a second negative terminal, the second positive terminal receives the second current signal in the first half of the period, and the second negative terminal receives the first current signal in the second half of the period.

[0008] In some embodiments of the application, the first half of the period of the first current signal received by the first positive terminal is divided into three stages in time sequence, in the first stage, the duty cycle of the first current signal received by the first positive terminal increases, in the middle stage, the duty cycle of the first current signal received by the first positive terminal remains unchanged, and in the last stage, the duty cycle of the first current signal received by the first positive terminal decreases.

[0009] The application provides different current signals by setting the duty cycle to control the light uniformizing member with different operation requirements.

[0010] In some embodiments of the application, the driving module comprises a control unit and a driving unit, the control unit is connected to the driving unit, the driving unit receives the control signal generated by the control unit and amplifies the control signal to generate the first current signal and the second current signal.

[0011] In some embodiments of the application, the light uniformizing device comprises a calibration unit provided with calibration parameters of the light uniformizing member; the control unit is connected to the calibration unit, and the control unit reads the calibration parameters in the calibration unit to generate the control signal.

[0012] The application connects the control unit to the calibration unit and reads the calibration parameters in the calibration unit, thereby calibrating the operation of the light uniformizing member and further improving the light uniformization and speckle elimination effect.

[0013] In some embodiments of the present application, the calibration unit comprises a first communication pin, the control unit comprises a second communication pin, the first communication pin is connected to the second communication pin, and the control unit reads the calibration parameter based on the second communication pin and the first communication pin.

[0014] In the present application, the communication pin is provided, so that the control unit can obtain the calibration parameter from the calibration unit, and output the alternating current required for the operation path of the matching light uniformization element and acting on the first coil and the second coil according to the calibration data, so that the light uniformization and spot elimination effect of the light uniformization element are better.

[0015] In some embodiments of the present application, the driving module comprises a first energizing signal output pin, a second energizing signal output pin, a third energizing signal output pin, and a fourth energizing signal output pin; the first energizing signal output pin and the second energizing signal output pin are respectively connected to two ends of the first coil, for outputting the first energizing signal to the first coil; and the third energizing signal output pin and the fourth energizing signal output pin are respectively connected to two ends of the second coil, for outputting the second energizing signal to the second coil.

[0016] In the present application, four energizing signal output pins are provided in the driving module, each of the energizing signal output pins is connected to different ports of the first coil and the second coil, so that the energizing signal is sent through the energizing signal output pin, the energizing of the first coil and the second coil can be controlled, and the direction of the current in the first coil and the second coil can be controlled, so as to change the magnetic field in the first coil and the second coil, so that the light uniformization element can operate according to the required movement state, and the light uniformization and spot elimination functions are realized.

[0017] In some embodiments of this application, the driving module includes a control unit and a driving unit. The control unit includes a first control signal output pin, a second control signal output pin, a third control signal output pin, and a fourth control signal output pin. The driving unit includes a first control signal receiving pin, a second control signal receiving pin, a third control signal receiving pin, and a fourth control signal receiving pin. The driving unit receives the control signal sent by the control unit via the first control signal output pin through the first control signal receiving pin, amplifies it, and outputs the first energized signal at the first energized signal output pin. The driving unit receives the control signal sent by the control unit via the second control signal output pin through the second control signal output pin. The signal receiving pin receives the control signal sent by the control unit via the second control signal output pin, and amplifies it to output the first power-on signal at the second power-on signal output pin; the driving unit receives the control signal sent by the control unit via the third control signal output pin via the third control signal receiving pin, and amplifies it to output the second power-on signal at the third power-on signal output pin; the driving unit receives the control signal sent by the control unit via the fourth control signal output pin via the fourth control signal receiving pin, and amplifies it to output the second power-on signal at the fourth power-on signal output pin.

[0018] This application sets up a number of control signal output pins corresponding to the number of energized signal output pins in the control unit, and sets up corresponding control signal receiving pins in the drive unit. The control signals output by the control signal output pins of the control cell can be amplified in the drive unit to generate energized signals received by different ports in the first and second coils, thereby driving the coils and enabling the light-diffusing device to operate.

[0019] In some embodiments of this application, the first control signal output pin outputs a control signal in the first half of the cycle, and the second control signal output pin outputs a control signal in the second half of the cycle; the third control signal output pin outputs a control signal in the first half of the cycle, and the fourth control signal output pin outputs a control signal in the second half of the cycle; the phase difference between the control signal output by the first control signal output pin and the control signal output by the third control signal output pin is one-quarter of a cycle, and the phase difference between the control signal output by the second control signal output pin and the control signal output by the fourth control signal output pin is one-quarter of a cycle.

[0020] This application sets the control signal output pin to output control signals at different time periods within a cycle, thereby causing the current direction of the first coil or the second coil to be different at different time periods within a cycle. As a result, the first coil or the second coil receives alternating current with positive and negative changes, thereby driving the operation of the light homogenizer to achieve the effects of light homogenization and spot elimination.

[0021] In some embodiments of this application, the light-diffusing device further includes: a support base; a motion plate, the motion plate being fixed to the support base by an elastic device; a magnetic device, the magnetic device being fixed to the motion plate; the light-diffusing element being fixed to the motion plate; the first coil and the second coil being fixed to the support base; the magnetic device being located above the first coil and the second coil; the magnetic force generated when the first coil and / or the second coil is energized drives the motion plate to move, thereby causing the light-diffusing element to move. Attached Figure Description

[0022] To more clearly illustrate the implementation methods in the embodiments of this application or related technologies, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0023] Figure 1 This is a schematic diagram of the appearance of a laser projection device according to an embodiment of this application;

[0024] Figure 2 This is a three-dimensional schematic diagram of a portion of the structure of a laser projection device according to an embodiment of this application;

[0025] Figure 3 This is a schematic diagram of the structure of an optomechanism shown in one embodiment of this application;

[0026] Figure 4 This is a partial structural schematic diagram of an optomechanism shown in one embodiment of this application;

[0027] Figure 5 This is a waveform diagram of the analog signal obtained by the first coil according to an embodiment of this application;

[0028] Figure 6 This is a schematic diagram of the structure of a light-diffusing device according to an embodiment of this application;

[0029] Figure 7 This is a schematic diagram of the structure of a light-diffusing device shown in another embodiment of this application;

[0030] Figure 8 This is a schematic diagram of the structure of a light-diffusing device shown in another embodiment of this application;

[0031] Figure 9 This is a schematic diagram of the structure of a light-diffusing device shown in another embodiment of this application;

[0032] Figure 10 This is a schematic diagram of the circuit board structure shown in one embodiment of this application;

[0033] Figure 11 This is a schematic diagram of the circuit board structure shown in another embodiment of this application;

[0034] Figure 12 This is a schematic diagram of the circuit board structure shown in another embodiment of this application;

[0035] Figure 13 This is a schematic diagram of the structure of the second socket shown in one embodiment of this application;

[0036] Figure 14 This is a schematic diagram of the structure of a control unit shown in one embodiment of this application;

[0037] Figure 15 This is a schematic diagram of the structure of a drive unit shown in one embodiment of this application;

[0038] Figure 16 This is a partial structural schematic diagram of a drive unit shown in one embodiment of this application;

[0039] Figure 17 This is a waveform diagram of the digital signal output by the control unit according to an embodiment of this application;

[0040] Figure 18 This is a schematic diagram of the voltage waveform of the first energized signal shown in an embodiment of this application.

[0041] Reference numerals: 100-Laser projection equipment, 102-First shell wall, 105-Fourth shell wall, 107-Top shell, 1051-Second heat dissipation hole, 1-Light source, 2-Optical engine, 3-Lens, 21-Beam shaper, 22-Light homogenizer, 23-Light valve, 24-Drive module, 221-First coil, 222-Second coil, 223-Support base, 224-Motion plate, 225-Elastic device, 226-Magnetic device, 227-Circuit board, 228-First socket, 229-Fixing device, 230-Calibration unit, 231-Light homogenizer. Detailed Implementation

[0042] To make the objectives, implementation methods and advantages of this application clearer, the exemplary implementation methods of this application will be clearly and completely described below with reference to the accompanying drawings of the exemplary embodiments of this application. Obviously, the described exemplary embodiments are only some embodiments of this application, and not all embodiments.

[0043] It should be noted that the brief descriptions of terms in this application are only for the convenience of understanding the embodiments described below, and are not intended to limit the embodiments of this application. Unless otherwise stated, these terms should be understood in their ordinary and common meaning.

[0044] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover but not exclusively include, for example, a product or device that includes a series of components is not necessarily limited to those that are explicitly listed, but may include other components that are not explicitly listed or that are inherent to such product or device.

[0045] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0046] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0047] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0048] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0049] Figure 1This is a schematic diagram of the appearance of a laser projection device according to an embodiment of this application. The laser projection device 100 includes a first housing, which may include a first housing wall 102, a second housing wall, a third housing wall, a fourth housing wall 105, a bottom shell, and a top shell 107. It can be understood that, for ease of illustration, the second housing wall, the third housing wall, and the bottom shell are... Figure 1 The image is not shown in the image.

[0050] The bottom shell and the top shell 107 can be arranged relative to each other. The first shell wall 102 and the third shell wall are the front side wall and the rear side wall of the equipment, respectively. The second shell wall and the fourth shell wall 105 can be the left side wall and the right side wall of the equipment, respectively.

[0051] Based on this, and by way of example, the second shell wall 103, the fourth shell wall 105, and the top shell 107 can be an integral structural component. This integral connector can be connected to the bottom shell via a threaded connector, and to the first shell wall 102 and the third shell wall via a snap-fit ​​connection. Of course, the first shell wall 102, the second shell wall, the third shell wall, the fourth shell wall 105, the bottom shell, and the top shell 107 can also be connected in other ways, and this application does not limit this.

[0052] In some embodiments, a second heat dissipation hole 1051 is provided on the fourth shell wall 105, and a first heat dissipation hole is provided on the second shell wall opposite to the fourth shell wall 105. The heat dissipation system provided in the laser projection device 100 can drive airflow from one of the first heat dissipation hole and the second heat dissipation hole 1051 to the other.

[0053] Figure 2 This is a three-dimensional schematic diagram of a portion of the structure of a laser projection device according to an embodiment of this application, as shown below. Figure 2 As shown, the laser projection device 100 includes a light source 1, an optical engine 2, and a lens 3. The light source 1 is used to provide an illumination beam. The optical engine is set in the optical path of the illumination beam and is used to adjust the illumination beam to obtain a projection beam. The lens 3 is used to image the projection beam.

[0054] For example, light source 1 can be a tri-color light source, comprising a red laser component, a blue laser component, a green laser component, and multiple optical lenses. These optical lenses can homogenize and converge the laser beam. Alternatively, light source 1 can also be a non-tri-color laser light source, i.e., it can be a monochromatic or dichromatic light source. A monochromatic light source can use a blue laser component to excite phosphors to produce two other primary colors of light (such as red and green fluorescence), or produce more than two colors of fluorescence. A dichromatic light source can use a blue laser component and a red laser component, with the blue laser component exciting phosphors to produce green fluorescence (or other colors of fluorescence).

[0055] For example, the optical engine 2 may include multiple lens groups, such as a total internal reflection (TIR) ​​prism and a reverse total internal reflection (RTIR) mirror, to form an illumination optical path so that the illumination beam can be incident on the core device in the optical engine 2, namely the light valve. The light valve is used to modulate the beam and cause the modulated projection beam to be incident on the lens group of the lens 3 for imaging. Furthermore, for example, the light valve can be a digital micromirror device (DMD); or, the light valve can be a liquid crystal on silicon (LCOS), both of which are applicable.

[0056] For example, lens 3 can be an ultra-short-throw projection lens, which typically includes a refractive mirror group and a reflective mirror group to receive the projection beam emitted after modulation by the optical engine 2 for imaging. Ultra-short-throw projection devices can achieve a smaller throw ratio (the throw ratio is the ratio of the vertical distance from the center point of the light-emitting surface of lens 3 to the plane of the projection screen to the width of the display area on the projection screen, where the width of the display area refers to the dimension of the display area along the horizontal direction), such as less than or equal to 0.3, or other values. Therefore, when the laser projection device 100 projects an image, it can be closer to the projection screen to reduce the overall space occupied by the projection display system; alternatively, lens 3 can also be a telephoto lens, which is less difficult to design and has a lower cost.

[0057] like Figure 3 As shown, in some embodiments, the optical engine 2 may include a beam shaper 21, a light homogenizer 22, and a light valve 23. The beam shaper 21 is used to receive the illumination beam emitted by the light source and perform shaping processing. The light homogenizer 22 is disposed in the optical path of the illumination beam and located between the light source 1 and the lens 3 to homogenize the light and eliminate speckles. The beam emitted by the light homogenizer 22 is modulated in the light valve 23 to obtain the projection beam.

[0058] Understandably, the beam shaper 21 can be configured according to the needs of different projection devices. For example, if it is necessary to perform operations such as transmission or reflection to change the direction of the light beam, or to change the size of the light spot, the beam shaper 21 may include structures such as lenses, mirrors, and beam splitters. The structure of the beam shaper 21 can be different depending on the different needs, and no specific restrictions are made here.

[0059] In some embodiments, a beam shaper may be added between the light valve 23 and the lens 3 to further shape the light output from the light valve 23 before projecting an image through the lens 3.

[0060] For example, the light-diffusing device 22 includes a light-diffusing element, which may include a diffusion wheel or a structure with a small light-diffusing element, such as using a diffusion sheet as the light-diffusing element. No specific limitation is made here. In one embodiment, taking a movable diffusion sheet as an example, the light-diffusing device 32 may include a coil. The coil can be powered by an external drive, causing current to flow in the coil, thereby generating a magnetic field that causes the light-diffusing device 32 to operate for light homogenization and speckle reduction.

[0061] like Figure 4 As shown, in some embodiments, the optomechanic further includes a drive module 24, which is connected to the homogenizing device 22.

[0062] Figure 4 This is a partial structural schematic diagram of an optomechanism shown in one embodiment of this application. In some embodiments, the beam homogenizer 22 includes a first coil 221 and a second coil 222. Of course, Figure 4 The first coil 221 and the second coil 222 in the diagram are for illustrative purposes only and should not be taken as shape references.

[0063] In other embodiments, the light-diffusing device 22 includes a circuit board, with the first coil 221 and the second coil 222 soldered to corresponding pads on the circuit board.

[0064] In this embodiment, both the first coil 221 and the second coil 222 have two ends, one end being regarded as a positive terminal and the other end as a negative terminal. The positive and negative terminals of the first coil 221 are soldered to the corresponding pads on the circuit board, and the positive and negative terminals of the second coil 222 are soldered to the corresponding pads on the circuit board.

[0065] The two ends of the first coil 221 and the second coil 222 are respectively connected to the driving module 24 and are energized by the driving module 24.

[0066] In some embodiments, the light homogenizing device 22 further includes a light homogenizing element, which may be a structure such as a moving diffuser. After the first coil 221 and / or the second coil 222 in the light homogenizing device 22 are driven and energized by the driving module 24, the magnetic force generated can make the light homogenizing element move, thereby realizing the functions of light homogenization and speckle elimination in the laser projection device.

[0067] Understandably, when the first coil 221 and / or the second coil 222 are energized, there should be alternating current with positive and negative changes, such as trapezoidal alternating current or sinusoidal alternating current, in the first coil 221 and / or the second coil 222. This alternating current with positive and negative changes is used as a driving current to drive the uniform light component to move.

[0068] In this embodiment, the driving module 24 is connected to the first coil 221 and the second coil 222. It sends a first energizing signal to the first coil 221 to energize the first coil 221, and sends a second energizing signal to the second coil to energize the second coil 222. The light-diffusing element moves under the magnetic force generated after the first coil 221 and / or the second coil 222 are energized.

[0069] In one embodiment, the phase difference between the first energizing signal and the second energizing signal is one-quarter of a cycle, thereby driving the motion trajectory of the light homogenizer to be circular or elliptical. The near-circular or elliptical trajectory of the light homogenizer enables it to achieve better light homogenization and spot reduction effects.

[0070] In some embodiments, the positive terminal of the two ports of the first coil is used as the first positive terminal, and the negative terminal of the two ports of the first coil is used as the first negative terminal. The first positive terminal receives the first energizing signal in the first half of the cycle, and the first negative terminal receives the first energizing signal in the second half of the cycle.

[0071] The positive terminal of the two ports of the second coil is used as the second positive terminal, and the negative terminal of the two ports of the second coil is used as the second negative terminal. The second positive terminal receives the second energizing signal in the first half of the cycle, and the second negative terminal receives the second energizing signal in the second half of the cycle.

[0072] In this embodiment, one rotation of the light-diffusing component is considered as one cycle. Within one cycle, the first positive terminal receives the first energizing signal in the first half of the cycle, and the first negative terminal receives the first energizing signal in the second half of the cycle.

[0073] Understandably, the first energizing signal is a digital signal. In the first half of the cycle, the first positive terminal receives the first energizing signal, and the first negative terminal receives an energizing signal with a duty cycle of zero. That is, the duty cycle of the digital signal waveform sent by the driving module received by the first negative terminal in the first half of the cycle is zero.

[0074] Correspondingly, in the latter half of the cycle, the first negative terminal receives the first energizing signal, and the first positive terminal receives an energizing signal with a zero duty cycle. Thus, by having the two ends of the first coil receive the first energizing signal in different half-cycles within one cycle, and the other end receiving an energizing signal with a zero duty cycle, the direction of the current in the first coil is changed. In the first half of the cycle, the current flows from the first positive terminal to the first negative terminal, and in the latter half of the cycle, the current flows from the first negative terminal to the first positive terminal. The first energizing signals applied to the two ends of the first coil in different half-cycles can be integrated to obtain the alternating current with positive and negative changes received by the first coil in one cycle. That is, by applying the first energizing signal with a non-zero duty cycle to the two ends of the first coil in different half-cycles, the analog signal received by the first coil in one cycle can be obtained. That is, the analog signal is an alternating current with positive and negative changes. Thus, the alternating current with positive and negative changes in the first coil can be used as a driving current to drive the motion of the light-diffusing element.

[0075] The energizing signal with a zero duty cycle is also a digital signal. The waveform of the digital signal corresponding to the first energizing signal is determined by the duty cycle. The waveform of the digital signal of the first energizing signal can determine the analog signal waveform of the AC power received by the first coil in one cycle.

[0076] The second coil is identical, and the second energizing signal is a digital signal. In the first half of the cycle, the second positive terminal receives the second energizing signal, and the second negative terminal receives an energizing signal with a zero duty cycle. That is, the digital signal waveform of the energizing signal received by the second negative terminal in the first half of the cycle has a zero duty cycle. In the second half of the cycle, the second negative terminal receives the second energizing signal, and the second positive terminal receives an energizing signal with a zero duty cycle. The second coil can receive alternating current with positive and negative changes in one cycle. The digital signal waveform of the second energizing signal determines the waveform of the analog signal received by the second coil. That is, the analog signal is alternating current with positive and negative changes. Thus, the alternating current with positive and negative changes in the second coil can be used to drive the motion of the light-shielding element.

[0077] Therefore, the phase difference between the first energizing signal and the second energizing signal proposed in this embodiment is one-quarter of a cycle. It can also be regarded as the phase difference between the first energizing signal received by the first positive terminal and the second energizing signal received by the second positive terminal being one-quarter of a cycle; the phase difference between the first energizing signal received by the first negative terminal and the second energizing signal received by the second negative terminal being one-quarter of a cycle.

[0078] Correspondingly, the phase difference between the energized signal with zero duty cycle received by the first negative terminal and the energized signal with zero duty cycle received by the second negative terminal is one-quarter of a cycle; the phase difference between the energized signal with zero duty cycle received by the first positive terminal and the energized signal with zero duty cycle received by the second positive terminal is one-quarter of a cycle.

[0079] In some embodiments, a first energizing signal and a second energizing signal are applied to the ends of a first coil and a second coil at different half-cycles. The first coil and the second coil can obtain corresponding analog signals. The duty cycles of the first energizing signal and the second energizing signal are different, and the waveforms of the obtained analog signals are different. In this embodiment, the waveform of the analog signal can be a sine wave, a trapezoidal wave, or a near-sine wave or a near-trapezoidal wave. This allows the first coil and the second coil to drive the motion trajectory of the light homogenizer to be circular, elliptical, or near-circular or near-elliptical under the analog signal of this waveform. This enables the light homogenizer to achieve better light homogenization and speckle reduction effects.

[0080] In this embodiment, the duty cycle of the first energizing signal and the second energizing signal can determine the waveform of the analog signal. Different duty cycle settings result in different waveforms of the analog signal. One cycle can be divided into multiple small cycles, and each small cycle can be set with a different duty cycle to obtain the analog signal with the desired waveform.

[0081] The analog signal can be an analog voltage signal or an analog current signal. At a certain temperature, the resistance of the first coil or the second coil is considered to be constant. Therefore, the waveforms of the analog voltage signal and the analog current signal can be considered to have the same shape (the values ​​may be different).

[0082] For the first coil, a first energizing signal is applied to the first positive terminal and an energizing signal with a zero duty cycle is applied to the first negative terminal in the first half of the cycle. In the second half of the cycle, the first energizing signal is applied to the first negative terminal and an energizing signal with a zero duty cycle is applied to the first positive terminal. Then, in one cycle, the digital voltage obtained by the first coil is the energizing signal received by the first positive terminal minus the energizing signal received by the first negative terminal. The energizing signal received by the first positive terminal is taken as PWM11 and the energizing signal received by the first negative terminal is taken as PWM12. If the energizing signal is a digital voltage signal, then the voltage of the first coil in one cycle is PWM11-PWM12. Thus, the analog voltage signal obtained by the first coil in one cycle can be obtained through PWM11-PWM12.

[0083] In some embodiments, taking a sine wave as an example, a period is divided into as many small periods as possible, and the first energizing signal and the second energizing signal are set with corresponding duty cycles in each small period, so that the waveform of the analog signal obtained by the first energizing signal acting on the first coil or the second energizing signal acting on the second coil is a sine wave or close to a sine wave.

[0084] In one embodiment, taking the analog signal as a trapezoidal wave as an example, one cycle is also divided into as many small cycles as possible. For the first half of the cycle of the first energized signal received by the first positive terminal, the first half of the cycle of the first energized signal received by the first positive terminal is divided into three stages according to time sequence. In the first stage, the duty cycle of the first energized signal received by the first positive terminal increases. In the middle stage, the duty cycle of the first energized signal received by the first positive terminal remains unchanged. In the last stage, the duty cycle of the first energized signal received by the first positive terminal decreases.

[0085] Specifically, within the preceding stage, the duty cycle of the first energized signal increases over multiple short cycles. Within the middle stage, the duty cycle of the first energized signal received by the first positive terminal remains constant over multiple short cycles. Within the following stage, the duty cycle of the first energized signal decreases over multiple short cycles. The duty cycle in the middle stage is the largest in the first energized signal. Thus, by applying different duty cycles to the first coil in the three stages, the analog signal obtained by the first coil is a trapezoidal wave, as shown in the reference. Figure 5 The diagram shows the waveform of the analog signal obtained by the first coil. Figure 5 In the diagram, the dashed line represents the waveform of the analog signal obtained by the first coil, and the solid line represents the waveform of the difference between the first energized signal applied to the first positive terminal of the first coil and the first energized signal applied to the first negative terminal of the first coil. Figure 5 The analog signal shown is a trapezoidal wave, of course, Figure 5 The diagram shows a trapezoidal wave obtained by dividing the first half of the period into four equal parts, with the first part corresponding to the previous stage and the duty cycle increasing in sequence, the middle two parts corresponding to the middle stage with the duty cycle remaining constant and at its maximum, and the last part corresponding to the next stage with the duty cycle decreasing. In other embodiments, these three stages can also be unequally divided to obtain trapezoidal waves of different shapes. No specific restrictions are imposed here. The same applies to the second half of the period, which will not be elaborated further here.

[0086] Depend on Figure 5 It can be seen that PWM11-PWM12 is positive in the first half of the cycle and negative in the second half of the cycle. Thus, the first energizing signal acts on the first coil, which can make the first coil receive alternating current with positive and negative changes to drive the light-diffusing element to rotate.

[0087] Figure 6 This is a schematic diagram of the structure of a light-uniforming device according to an embodiment of this application, as shown below. Figure 6 As shown, the light-diffusing device 22 includes a support base 223, which is a non-conductive structure used to support the light-diffusing device.

[0088] In some embodiments, the light-diffusing device also includes a motion plate 224, which is fixed to the support base 223 by an elastic device 225.

[0089] The material of the 224 sports board is not limited; it can be plastic or metal sheet, etc.

[0090] The elastic device 225 can be made of an elastic material, such as a sheet, a filament, or a spring. The elastic device 325 can be connected to the support base 223 and the moving plate 224 by means of adhesive or screw fixing.

[0091] The magnetic device 226 is attached to the motion plate 224, so that there is a certain gap between the motion plate 224 and the support base, so as to support the movement space of the motion plate 224 relative to the support base 223.

[0092] In one embodiment, the light-diffusing device further includes a magnetic device 226, which is fixed on the motion plate 225.

[0093] In this embodiment, corresponding to the first coil and the second coil, there are two magnetic devices 226. On the horizontal plane where the moving plate 225 is located, one magnetic device 226 is placed along the first direction and the other magnetic device is placed along the second direction. That is, the extension directions of the two magnetic devices 226 are orthogonal in the plane where the moving plate 225 is located. If the plane where the moving plate 225 is located is regarded as a horizontal plane, then the horizontal plane has a two-dimensional coordinate axis. The first direction can be regarded as the X-axis direction and the second direction is the Y-axis direction.

[0094] Correspondingly, both the first coil and the second coil are fixed on the support base. The first coil and the second coil can be fixed by adhesive. The first coil extends along the first direction and the second coil extends along the second direction. That is, the extension directions of the first coil and the second coil are orthogonal to the plane where the support base 223 is located.

[0095] A magnetic device 226 is placed above the first coil, extending along a first direction, and a magnetic device 226 is placed above the second coil, extending along a second direction.

[0096] In this embodiment, after the first coil is energized and / or the second coil is energized, a magnetic field is generated around the first coil and / or the second coil. This magnetic field is similar to the magnetic field of a bar magnet. The magnetic device 226 is located in the magnetic field generated by the first coil and / or the second coil, and thus acts on the magnetic field to obtain the magnetic force, causing the magnetic device 226 to move relative to the first coil and / or the second coil. This causes the magnetic device 226 to drive the moving plate 224 to move relative to the support base 223, thereby causing the light homogenizer 231 to move. The first coil and / or the second coil contain an analog signal of trapezoidal wave, sine wave or other waveform to drive the movement trajectory of the light homogenizer 231 to be circular or elliptical or close to circular or close to elliptical. When the movement trajectory of the light homogenizer 231 is in the above shape, better light homogenization and spot elimination effects can be achieved.

[0097] In some embodiments, the light-diffusing device may further include a circuit board 227, with the positive and negative terminals of the first coil and the second coil soldered to the corresponding pads on the circuit board 227. Through the circuit board 227, the positive and negative terminals of the first coil and the second coil are then connected to the four power-on signal output pins in the drive module via PCB wiring, sockets, and connecting wires.

[0098] In other embodiments, the support base 223 and the motion plate 224 may have a hollow structure in the middle, so that the light processed by the beam shaper can pass through the hollow area in the middle and be uniformly uniform by the moving light homogenizer 231 to achieve spot removal and color uniformity.

[0099] This embodiment proposes a light-uniforming device for use in laser projection equipment, which can perform light uniformity and speckle reduction processing to improve the quality of the projected image.

[0100] Figure 7 This is a schematic diagram of the structure of a light-diffusing device shown in another embodiment of this application. It is a schematic diagram of the structure when the light-diffusing element in the light-diffusing device is a diffuser. Figure 7 As shown, the circuit board 227 of the light-diffusing device in this embodiment is also provided with a first socket 228. The light-diffusing device can be connected to external devices through the first socket 228, such as a drive module. The light-diffusing device can be driven to move by the signal input from the drive module to achieve light diffusing and spot elimination.

[0101] In some embodiments, the circuit board 227 is further provided with a calibration unit 230. However, with the presence of the calibration unit 230, the light homogenizing device can be regarded as a calibrable light homogenizing device. The calibration unit 230 is provided with calibration parameters, and the operating trajectory and operating mode of the light homogenizing device can be adjusted in real time according to the calibration parameters to better achieve light homogenization and spot elimination.

[0102] In some embodiments, the calibration unit 230 can be connected to the drive module via the first socket 228. The drive module can obtain calibration parameters from the calibration unit 230 to output a first power-on signal and a second power-on signal to control the operation of the light homogenizer. In some embodiments, the drive module can be directly connected to the calibration unit 230 by soldering to access the calibration parameters.

[0103] Figure 8 This is a schematic diagram of the structure of a light-diffusing device according to another embodiment of this application. Figure 8 The structural schematic diagram shown is as follows Figure 7 A schematic diagram of another angle of the uniform light device, based on Figure 7 and Figure 8 It can be seen that... Figure 7 and Figure 8 It also includes a fixing device, and the elastic device 325 can be connected to the support base 223 and the moving plate 224 through the fixing device 229. Figure 8 and Figure 9 The fixing device 229 shown is a screw.

[0104] Figure 7 In the middle, the areas indicated by A and B below the motion plate are provided with coils and magnetic devices. For example, the area indicated by A below the motion plate is provided with a first coil and a magnetic device opposite to the first coil, and the area indicated by B below the motion plate is provided with a second coil and a magnetic device opposite to the second coil. The first coil and the second coil are soldered on the circuit board 227.

[0105] Figure 8 This is a schematic diagram of the structure of a light-diffusing device shown in another embodiment of this application, and... Figure 9 and Figure 9 The light-diffusing devices in the middle are different. Figure 9 The light-diffusing device shown in the diagram includes a first coil 221 and a second coil 223, and a magnetic device 226 opposite to the first coil 221. Figure 7 to Figure 9 The homogenizing device shown does not have a calibration unit, and Figure 4 The fixing device 229 is not a screw, but is connected to the support base 223 and the moving plate 224 by dispensing glue, that is, the elastic device 325 is connected to the support base 223 and the moving plate 224 by dispensing glue.

[0106] Understandable Figure 10 The structure of the light-diffusing device in this example is exemplary. In other embodiments, the light-diffusing device may have other structures, and no specific limitations are made here.

[0107] In some embodiments, such as Figure 10As shown, the driving module 24 includes four power-on signal output pins, namely a first power-on signal output pin, a second power-on signal output pin, a third power-on signal output pin, and a fourth power-on signal output pin. The first and second power-on signal output pins are respectively connected to the two ends of the first coil 221 to output a first power-on signal to the first coil 221; the third and fourth power-on signal output pins are respectively connected to the two ends of the second coil 222 to output a second power-on signal to the second coil 222.

[0108] In this embodiment, the first power-on signal output pin and the second power-on signal output pin are respectively connected to the first positive terminal and the first negative terminal of the first coil, and the third power-on signal output pin and the fourth power-on signal output pin are respectively connected to the second positive terminal and the second negative terminal of the second coil.

[0109] Understandably, since the first energizing signal output pin and the second energizing signal output pin are respectively connected to the first positive terminal and the first negative terminal of the first coil, the first energizing signal output pin and the second energizing signal output pin can be controlled to output a first energizing signal to the first coil 221 at different time periods within a cycle, thereby changing the direction of the current in the first coil 221. For example, if the first energizing signal output pin outputs a first energizing signal to the first coil 221, and the second energizing signal output pin outputs an energizing signal with a duty cycle of zero to the first coil 221, then the current flow in the first coil 221 will be from the port connected to the first energizing signal output pin to the port connected to the second energizing signal output pin. Similarly, if the second energizing signal output pin outputs a first energizing signal to the first coil 221, and the first energizing signal output pin outputs an energizing signal with a duty cycle of zero to the first coil 221, then the current flow in the first coil 221 will be from the port connected to the second energizing signal output pin to the port connected to the first energizing signal output pin.

[0110] Just as the first and second energizing signal output pins can change the direction of the current in the first coil 221 by outputting the first energizing signal to the first coil 221, the third and fourth energizing signal output pins can also change the direction of the current in the second coil 222 by outputting the second energizing signal to the second coil 222. For details, please refer to the method of changing the direction of the current in the first coil 221, which will not be repeated here.

[0111] In some embodiments, the first coil is energized based on a first energizing signal, and the second coil is energized based on a second energizing signal, so that the light-diffusing element moves under the magnetic force generated after the first coil 221 and / or the second coil 222 are energized.

[0112] In this embodiment, at a certain point in time, the first coil is energized. At this time, the waveform of the analog signal in the second coil has a phase difference with the waveform of the analog signal in the first coil. The light homogenizer can move under the magnetic force generated after the first coil and / or the second coil are energized.

[0113] In this embodiment, four power-on signal output pins are set in the driving module. Each power-on signal output pin is connected to a different port of the first coil and the second coil. The power-on signal is emitted through the channel signal output pin, which can control the power supply of the first coil and the second coil and control the direction of the current in the first coil and the second coil. In this way, the magnetic field in the first coil and the second coil is changed, so that the light-diffusing component can operate according to the required motion trajectory to achieve the effects of light diffusing and spot elimination.

[0114] In some embodiments, the drive module includes a control unit and a drive unit. The control unit is connected to the drive unit, and the drive unit receives a control signal from the control unit and amplifies the control signal to generate a first energizing signal and a second energizing signal.

[0115] Understandably, the control signal is also a digital signal, and its waveform is the same as that of the first and second energizing signals, but with different amplitudes. Similarly, the duty cycle of the control signal is the same as that of the first and second energizing signals, but with different amplitudes.

[0116] In this embodiment, the control unit can output a control signal, which can determine the waveform (shape, not amplitude) of the analog signal obtained by the first coil or the second coil. However, the control signal is insufficient to drive the light-diffusing element to operate. Therefore, the driving unit first amplifies the control signal output by the control unit to obtain a first energizing signal and a second energizing signal that can drive the light-diffusing element to operate. The first energizing signal and the second energizing signal are applied to the corresponding coils. The coils receive alternating current with positive and negative changes, such as trapezoidal wave alternating current, sine wave alternating current, or alternating current with other waveforms. This alternating current serves as the driving current to drive the light-diffusing element to move. Of course, the waveform of the alternating current can also be other shapes, which are not specifically limited here.

[0117] In one embodiment, the control unit is provided with a control signal output pin, which is connected to the control signal receiving pin of the drive unit. The drive unit receives the control signal sent by the control signal output pin through the control signal receiving pin and amplifies the control signal to generate a first energizing signal and a second energizing signal.

[0118] In this embodiment, the control signal is a digital signal. For example, if the control signal is a digital voltage signal, its waveform can be determined by the waveform of the alternating current acting on the first or second coil. In this embodiment, the control unit outputs a control signal, which is determined by the motion trajectory required by the light homogenizer. The motion trajectory required by the light homogenizer is confirmed by the waveform of the alternating current acting on the first and second coils. The duty cycle in the output control signal determines the area of ​​the motion trajectory. Setting the motion trajectory to be circular or elliptical can further improve the light homogenizing effect of the light homogenizer. When the alternating current waveform acting on the first and second coils is a trapezoidal wave, the duty cycle of the digital signal during the constant duty cycle phase determines the area of ​​the circular or elliptical motion trajectory. The larger the duty cycle, the larger the motion amplitude. However, the control signal output by the control unit has no analog driving capability. Therefore, the digital signal needs to be processed by the driving unit for amplification to obtain the first and second energizing signals that can drive the circuits of the first and second coils.

[0119] In some embodiments, the light homogenizing device can be divided into calibrable light homogenizing devices and non-calibrable light homogenizing devices. The calibrable light homogenizing device includes a calibration unit and has a calibration function. This calibrable light homogenizing device can be applied to laser projection equipment with high projection quality. The calibrable light homogenizing device can adjust parameters in real time to determine the control mode of the light homogenizing component according to different light homogenizing requirements. Specifically, the calibrable light homogenizing device can drive the vibration of the light homogenizing component according to the current waveform generated by the parameters in the calibration unit, thereby ensuring the consistency of the vibration trajectory and thus ensuring good speckle reduction and light homogenizing effect. On the other hand, the non-calibrable light homogenizing device does not include a calibration unit and has no calibration function. The non-calibrable light homogenizing device can only drive the vibration of the light homogenizing component according to the AC waveform generated by preset parameters. It cannot calibrate the vibration of the light homogenizing component in real time. The non-calibrable light homogenizing device can achieve light homogenization and speckle reduction effects, and the control method is simple and the cost is lower than that of the calibrable light homogenizing device.

[0120] In this embodiment, for non-calibrable light-diffusing devices, the digital signal output by the control unit is a preset control signal; while for calibrable light-diffusing devices, the calibration unit inside is equipped with calibration parameters for the light-diffusing device. The control unit is connected to the calibration unit. The control unit generates a control signal that matches the calibration parameters based on the calibration parameters read from the calibration unit. The signal after the control signal passes through the driving unit serves as the driving waveform signal for the light-diffusing device, namely the first power-on signal and the second power-on signal.

[0121] The calibration parameters may include duty cycle, operating frequency, and phase. Using these calibration parameters, the control unit can generate corresponding control signals, thereby causing the light homogenizer to move according to the motion trajectory corresponding to the calibration parameters.

[0122] Figure 11 This is a schematic diagram of the circuit board structure shown in one embodiment of this application. The circuit board is a circuit board for a non-calibrable homogenizing device, and in... Figure 11 The light-diffusing device also includes a first socket. The first positive terminal, first negative terminal, second positive terminal, and second negative terminal of the first coil and the second coil are connected to the corresponding pins of the first socket. The X+ and X- pins are connected to the first positive terminal and the first negative terminal of the first coil, respectively. X+ is considered the positive pole of the first coil, and X- is considered the negative pole of the first coil. They are connected to pins 1 and 2 of the first socket. Y+ and Y- are the pins connecting the two ends of the second coil. Y+ is considered the positive pole of the second coil and is connected to the second positive terminal. Y- is considered the negative pole of the second coil and is connected to the second negative terminal. They are connected to pins 3 and 4 of the second socket. In the first socket, the NC pins corresponding to pins 5-10 are empty pins and have no other purpose. The first power-on signal output pin, the second power-on signal output pin, the third power-on signal output pin, and the fourth power-on signal output pin in the driving module can be connected to the first coil and the second coil through the corresponding pins on the first socket.

[0123] Of course, it is understandable that the first socket may not be provided on the circuit board. In this case, the power-on signal output pin in the drive module is connected to the ports of the first and second coils by soldering it to the circuit board.

[0124] In some embodiments, the calibration unit in the calibrable light homogenizer may be an EEPROM (Electrically Erasable Programmable Read Only Memory) or an MCU (Microcontroller Unit).

[0125] The calibration unit includes a first communication pin, and the control unit includes a second communication pin. The first communication pin is connected to the second communication pin, so that the control unit can access the calibration parameters in the calibration unit through the second communication pin and the first communication pin, thereby generating the corresponding control signal.

[0126] In this embodiment, the first communication pin and the second communication pin can be connected by soldering them onto a circuit board. In other embodiments, the light-diffusing device further includes a first socket, which is provided with a first communication socket pin; the driving module further includes a second socket, which is provided with a second communication socket pin; the first communication pin and the first communication socket pin can be connected by a line, and the second communication pin and the second communication socket pin can be connected by a line, so that the first communication pin and the second communication pin are connected.

[0127] Figure 11This is a schematic diagram of the circuit board structure shown in another embodiment of this application, wherein the calibration unit is an EEPROM. Figure 12 In the diagram, I2C_SCL and I2C_SDA are the first communication pins, GND is the ground terminal, and VCC is the power supply pin, in units of 3.3V (volts), which supplies power to the calibration unit circuit. Figure 12 Pins 9 and 10 of the first socket are designated as the first communication socket pins, and the pins of the calibration unit are connected one-to-one with pins 1-10 on the first socket.

[0128] Figure 13 This is a schematic diagram of a circuit board structure shown in another embodiment of this application. The calibration unit is an MCU, and RIGX and TRIGY are trigger pins. TRIGX corresponds to the control signal of the first coil, and TRIGY corresponds to the signal in the second coil. When TRIGX is active, the parameters of the first coil, such as phase, operating frequency, and duty cycle, can be read through the communication pin. When TRIGY is active, the parameters of the second coil, such as phase, operating frequency, and duty cycle, can be read through the I2C communication pin. Figure 13 Pins 9 and 10 of the first socket are designated as the first communication socket pins. Pins 1-10 of the calibration unit are connected one-to-one with pins 1-10 of the first socket.

[0129] Figure 13 This is a schematic diagram of the structure of the second socket according to an embodiment of this application, showing the different logic pins connected to the second socket. For example, pins 1 and 2 are connected to X+ and X- at both ends of the first coil, pin 4 is connected to the power supply, pin 7 is connected to GND, etc. Therefore, pins 9 and 10 are the pins of the second communication socket. Of course, Figure 13 The illustration shown is illustrative. In other embodiments, the first socket may also include other numbers of pins, corresponding to different serial numbers, as long as they include those present. Figure 12 The 10 logic pins shown are sufficient.

[0130] In this embodiment, through Figure 11 The second socket in Figure 10 or Figure 10 The first socket in the system can connect the first communication pin and the second communication pin, thereby connecting the control unit and the calibration unit.

[0131] Understandably, the second socket can also be determined based on different light-diffusing devices, such as those used for... Figure 11 In the circuit board structure, the second socket may only exist with... Figure 11 The logic pins shown in the first socket are sufficient, while for... Figure 12 In the circuit board structure, the second socket may only exist with... Figure 12 The logic pins shown in the first socket are sufficient for this purpose. Figure 13In the circuit board structure, the second socket may only exist with... Figure 13 The logic pins shown in the first socket are sufficient.

[0132] Of course, to accommodate different types of light-diffusing devices, the second socket may include, for example... Figure 10 to Figure 12 The logic pins shown can also be configured to include the first socket in all homogenizing devices, such as... Figure 13 The logic pins shown are, i.e. Figure 14 The first socket in each includes, for example: Figure 15 The logic pins shown eliminate the need for different sockets for different light-diffusing devices, thus improving production efficiency.

[0133] In some embodiments, taking a diffuser as an example of a light-diffusing element in a light-diffusing device, the motion frequency and amplitude of each diffuser are not exactly the same due to the influence of the assembly, tolerance, and operating temperature of the diffuser. Therefore, each diffuser has a separate calibration parameter stored in the calibration unit. When the light-diffusing device is working, the control unit reads the calibration parameter stored in the calibration unit, thereby generating control signals for the corresponding two coils. The control signal passes through the drive unit to obtain the drive signals for the two coils, namely the first energizing signal and the second energizing signal, which drive the diffuser to vibrate the drive current according to the current waveform generated by the accurate parameters, thereby ensuring the consistency of the vibration trajectory and thus ensuring good spot removal and light-diffusing effect.

[0134] The vibration consistency of the uncalibrated light homogenizer is determined by preset parameters. The control unit generates a control signal based on the preset parameters, which can be determined by the operating frequency, duty cycle, and phase difference parameters of the drive current waveform corresponding to the actual light homogenizer's required motion trajectory.

[0135] Figure 14 This is a schematic diagram of the structure of a control unit shown in an embodiment of this application. In this embodiment, the control unit can be an MCU. The control signal output pins in the control unit include a first control signal output pin RA4, a second control signal output pin RA5, a third control signal output pin PB3, and a fourth control signal output pin PB2.

[0136] Figure 14 This is a schematic diagram of the structure of a driving unit shown in an embodiment of this application. The driving unit can be a driving chip. The control signal receiving pins in the driving unit include a first control signal receiving pin AIN1 connected to a first control signal output pin, a second control signal receiving pin AIN2 connected to a second control signal output pin, a third control signal receiving pin BIN1 connected to a third control signal output pin, and a fourth control signal receiving pin BIN2 connected to a fourth control signal output pin.

[0137] In this embodiment, the drive unit receives the control signal PWM1 sent by the first control signal output pin RA4 through the first control signal receiving pin AIN1, and performs operational amplification processing to output the first power-on signal through the first power-on signal output pin. At this time, the first power-on signal is the digital signal received by the first positive terminal of the first coil, and the first power-on signal is regarded as the positive voltage drive digital signal of the first coil.

[0138] The drive unit receives the control signal PWM2 sent by the second control signal output pin RA5 through the second control signal receiving pin AIN2, and performs operational amplification processing to output the first power-on signal through the second power-on signal output pin. At this time, the first power-on signal is the digital signal received by the first negative terminal of the first coil. The first power-on signal is regarded as the negative voltage drive digital signal of the first coil.

[0139] By driving the digital signal with the positive voltage of the first coil and the digital signal with the negative voltage of the first coil, the voltage driving digital signal of the first coil can be obtained, thereby obtaining the analog signal of the first coil, that is, the alternating current received by the first coil. This alternating current signal drives the light-diffusing element to vibrate.

[0140] The drive unit receives the control signal PWM3 sent by the third control signal output pin PB3 through the third control signal receiving pin BIN1, and performs operational amplification processing to output a second power signal at the third power signal output pin. The second power signal is the digital signal received by the second positive terminal of the second coil, and the second power signal is regarded as the positive voltage drive digital signal of the second coil.

[0141] The drive unit receives the control signal PWM4 sent by the fourth control signal output pin PB2 through the fourth control signal receiving pin BIN2, and performs operational amplification processing to output a second energizing signal at the fourth energizing signal output pin. The second energizing signal is the digital signal received by the second negative terminal of the second coil, and the second energizing signal is regarded as the negative voltage drive digital signal of the second coil.

[0142] By driving the digital signal with the positive voltage of the second coil and the digital signal with the negative voltage of the second coil, the voltage driving digital signal of the second coil can be obtained, thereby obtaining the analog signal of the second coil, which is the AC current received by the first coil. This AC current signal drives the light-diffusing element to vibrate with the AC current driving signal.

[0143] In this embodiment, the control signals output by the four control signal output pins of the control unit are PWM (Pulse Width Modulation) digital signals. The first control signal output pin RA4 outputs a PWM1 signal connected to the X+ port of the first coil, the second control signal output pin RA5 outputs a PWM2 signal connected to the X- port of the first coil, the third control signal output pin BIN1 outputs a PWM3 signal connected to the Y+ port of the second coil, and the fourth control signal output pin BIN2 outputs a PWM4 signal connected to the Y- port of the second coil.

[0144] In one embodiment, the control unit is powered by 3.3V to generate a voltage waveform acting on the homogenizing device, and outputs four control signals PWM1, PWM2, PWM3, and PWM4, with a voltage level of 3.3V. These four digital signals reach the drive unit, are amplified, and then a 5V energizing signal is obtained, corresponding to the 5V voltage requirement of the first and second coils. This energizing signal is a voltage-driven digital signal, which is output through the corresponding energizing signal output pin to obtain a trapezoidal or sinusoidal alternating current with positive and negative changes in the first and second coils. The first and second coils vibrate under the drive of the alternating current. It is understood that the 3.3V of the control unit and the 5V of the drive unit are exemplary. In other embodiments, the voltage of the control unit can also be 2.2V, 3V, 3.2V, etc., and different values ​​can be set according to different needs. No specific limitation is made here. Similarly, the voltage of the drive unit can also be 5.6V, 6V, 7V, etc., and different values ​​can also be set according to different needs. No specific limitation is made here.

[0145] Similar to the first and second energizing signals, within one cycle, the first control signal output pin outputs a control signal in the first half of the cycle. This first half of the output control signal is processed by the operational amplification of the drive unit to obtain the first energizing signal input to the first positive terminal of the first coil in the first half of the cycle. The second control signal output pin outputs a control signal in the second half of the cycle. This second half of the output control signal is processed by the operational amplification of the drive unit to obtain the first energizing signal input to the first negative terminal of the first coil in the second half of the cycle.

[0146] The third control signal output pin outputs a control signal in the first half of the cycle. This first half of the output control signal is processed by the operational amplification of the drive unit to obtain a second energizing signal input to the second positive terminal of the second coil in the first half of the cycle. The fourth control signal output pin outputs a control signal in the second half of the cycle. This second half of the output control signal is processed by the operational amplification of the drive unit to obtain a second energizing signal input to the second negative terminal of the second coil in the second half of the cycle.

[0147] The phase difference between the control signal output by the first control signal output pin and the control signal output by the third control signal output pin is the same as the phase difference between the first and second power-on signals. The phase difference between the control signal output by the second control signal output pin and the control signal output by the fourth control signal output pin is also one-quarter of a cycle.

[0148] Figure 14 In the middle, a 0.1u (0.1 microfarad) capacitor C1 is set between VCC and the ground terminal, and the control unit is set with a trigger pin, corresponding to TRIGX and TRIGY. It can be connected to the calibration unit through the first socket and the second socket to obtain the parameters of the first coil and the second coil.

[0149] and Figure 14 Pins 9 and 8 are designated as the second communication pins, which can be connected to the calibration unit via the first socket and the second socket to read calibration parameters.

[0150] Figure 9 The PA2 and PA1 pins are connected to RXD and TXD respectively, which are serial communication ports. The RESET pin is connected to socket XP1, which has power supply VCC and ground. It can be used for online programmable programs and to download programs to the control unit. A 47k (4700 ohm) resistor R5 and a 1n (1 nanofarad) capacitor C3 are connected between VCC and ground.

[0151] Figure 15 The second communication pin is connected to resistors R3 and R4 of 4.7kΩ. The EXTCLK (external clock) of this control unit is connected to a crystal oscillator. Figure 15 The crystal oscillator is 8MHz. It is powered by VCC and a 0.1u capacitor C1 is set between VCC and ground. The OE (enable) pin of the crystal oscillator is pulled high by an external 4.7k resistor R1 to enable it. A 22R (22 ohms) resistor R2 is connected between the output pin and the EXTCLK pin of the crystal oscillator.

[0152] Figure 16In the diagram, the VM pin of the drive unit is connected to a 5V voltage. A 22u (22 microfarad) capacitor C4 and a 0.1u capacitor C5 are connected in parallel between the VM pin and ground. Resistors R6-R9 with a value of 0 are connected in series between the control signal output pin of the control unit and the digital signal input pin of the drive unit. The EN (enable) pin is connected to a 3.3V voltage. A resistor R10 with a value of 0 and a 10k (10000 ohm) resistor R11 are set between VCC and ground. AOUT1 is the first power-on signal output pin, AOUT2 is the second power-on signal output pin, BOUT1 is the third power-on signal output pin, and BOUT2 is the fourth power-on signal output pin.

[0153] Figure 14 In the SDA pin, AISEN and BISEN (pins used to change the resistance value of the external resistor, thereby setting the output current) are connected to ground. SCL is the synchronous clock line pin, and SDA is the data line pin. Figure 15 The SCL and SDA pins of the drive unit are connected to an external 3.3V power supply. Pull-up is not required, and pull-down is the default. A 10k / NC (NC refers to reserved, but not surface-mount) resistor R13 is connected in series between the SCL pin and the power supply voltage. A 10k resistor R15 is connected in series between the SCL pin and ground. A 10k / NC resistor R14 is connected in series between the SDA pin and the power supply voltage. A 10k resistor R16 is connected in series between the SDA pin and ground.

[0154] The nFAULT pin (fault indication pin) is connected to a 3.3V power supply, and a 10k resistor R12 is connected in series with the power supply.

[0155] certainly, Figure 14 and Figure 15 The relevant structures shown in this embodiment are illustrative; other structures may be used in other embodiments, as long as they implement the functions shown in this embodiment. No specific limitations are imposed here. Figure 17 and Figure 17 The parameter settings of the relevant structures are illustrative. In other embodiments, they may be other parameters. The parameter settings are sufficient to enable the relevant structures to achieve the functions proposed in this embodiment.

[0156] In this embodiment, the phase difference between the control signal output by the first control signal output pin and the control signal output by the third control signal output pin is one-quarter of a cycle, and the phase difference between the digital signal output by the second control signal output pin and the control signal output by the fourth control signal output pin is one-quarter of a cycle.

[0157] Since the control signal is a digital signal, if we consider this digital signal as a digital voltage signal, which is a voltage waveform signal, then the phase difference between the waveform of the digital voltage signal output by the first control signal output pin and the waveform of the digital voltage signal output by the third control signal output pin is one-quarter of a cycle, and the phase difference between the waveform of the digital voltage signal output by the second control signal output pin and the waveform of the digital voltage signal output by the fourth control signal output pin is one-quarter of a cycle.

[0158] In contrast, the phase difference between the waveform PWM1 of the first power-on signal output by the first power-on signal output pin (which is connected to the positive terminal of the first coil and can be regarded as a positive digital signal) and the waveform PWM3 of the second power-on signal output by the third power-on signal output pin (which is connected to the negative terminal of the first coil and can be regarded as a positive digital signal) is one-quarter of a cycle, or 90°. The phase difference between the waveform PWM2 of the first power-on signal output by the second power-on signal output pin (which is connected to the negative terminal of the second coil and can be regarded as a negative digital signal) and the waveform PWM4 of the second power-on signal output by the fourth power-on signal output pin (which is connected to the negative terminal of the second coil and can be regarded as a negative digital signal) is one-quarter of a cycle, thereby realizing the control of the circular or elliptical motion trajectory of the light-diffusing component.

[0159] Similarly, the first and second energizing signals are also digital signals, such as digital voltage signals. The phase difference between the waveform PWM1 of the positive digital voltage signal output by the first energizing signal output pin and the waveform PWM3 of the digital voltage signal of the second energizing signal output by the third energizing signal output pin is one-quarter of a cycle. The phase difference between the waveform PWM2 of the digital voltage signal of the first energizing signal output by the second energizing signal output pin and the waveform PWM4 of the digital voltage signal of the second energizing signal output by the fourth energizing signal output pin is one-quarter of a cycle.

[0160] One cycle shown in this embodiment can be regarded as the time for the uniform light element to complete one revolution.

[0161] In this embodiment, within the cycle of one revolution of the light-monitoring component, the first control signal output pin outputs a control signal in the first half of the cycle, the second control signal output pin outputs a control signal in the second half of the cycle; the third control signal output pin outputs a control signal in the first half of the cycle, and the fourth control signal output pin outputs a control signal in the second half of the cycle. It can be understood that the output control signals shown here are control signals with duty cycles that are not all zero.

[0162] Within one revolution of the light-diffusing component, the first control signal output pin outputs a control signal in the first half of the cycle, i.e., a digital signal with a duty cycle not entirely zero. In the second half of the cycle, the first control signal output pin also outputs a digital signal, but this digital signal is different from the control signal output in the first half of the cycle. In the second half of the cycle, the first control signal output pin outputs a digital signal with a duty cycle of 0. Taking the digital signal output by the control unit as a digital voltage signal as an example, in the second half of the cycle, the first control signal output pin will output a digital signal with a duty cycle of 0. Similarly, the second control signal output pin outputs a digital signal with a duty cycle of 0 during the first half of the cycle and a control signal with a duty cycle that is not entirely zero during the second half of the cycle; the third control signal output pin outputs a control signal with a duty cycle that is not entirely zero during the first half of the cycle and a digital signal with a duty cycle of 0 during the second half of the cycle; and the fourth control signal output pin outputs a digital signal with a duty cycle of 0 during the first half of the cycle and a control signal during the second half of the cycle.

[0163] It is understood that the control signal output pin of the control unit proposed in this embodiment outputs a digital signal with a non-zero duty cycle. At other times, the output pin does not output a control signal, and is therefore considered a digital signal with a zero duty cycle. Thus, the zero-duty-cycle digital signal and the non-zero-duty-cycle control signal output by the control signal output pin, after being amplified by the drive unit, are applied to the first and second coils to generate AC current driving the first and second coils. The waveform of the control signal output by the output pin determines the waveform of the AC current. It should be understood that the control signal output by the output pin corresponds to the energizing signal output by the energizing signal output pin in the drive unit. After amplification by the drive unit, the control signal is amplified to obtain the first energizing signal and the second energizing signal. If the first control signal output pin outputs a control signal in the first half of the cycle, the first control signal receiving pin receives the control signal, and after amplification by the drive unit, the first energizing signal output pin is amplified to obtain the first energizing signal output in the first half of the cycle. The first energizing signal (the signal received by the first positive terminal of the first coil) is output within half a cycle. The second control signal output pin outputs a control signal within the second half a cycle. The second control signal receiving pin receives the control signal and, after amplification by the drive unit, obtains the first energizing signal output by the second energizing signal output pin within the second half a cycle (the signal received by the first negative terminal of the first coil). The third control signal output pin outputs a control signal within the first half a cycle. The third control signal receiving pin receives the control signal and, after amplification by the drive unit, obtains the second energizing signal output by the third energizing signal output pin within the first half a cycle (the signal received by the second positive terminal of the second coil). The fourth control signal output pin outputs a control signal within the second half a cycle. The fourth control signal receiving pin receives the control signal and, after amplification by the drive unit, obtains the second energizing signal output by the fourth energizing signal output pin within the second half a cycle (the signal received by the second negative terminal of the second coil).

[0164] In this embodiment, a cycle can be divided into a first half-cycle and a second half-cycle. For a coil, the direction of the coil current is opposite in the first half-cycle and the second half-cycle. Thus, for the first coil, the first control signal output pin outputs a control signal in the first half-cycle, while the second control signal output pin outputs a digital signal with a duty cycle of 0. In the second half-cycle, the second control signal output pin outputs a control signal, while the first control signal output pin outputs a digital signal with a duty cycle of 0. For the second coil, the third control signal output pin outputs a control signal in the first half-cycle, while the fourth control signal output pin outputs a digital signal with a duty cycle of 0. In the second half-cycle, the fourth control signal output pin outputs a control signal, while the third control signal output pin outputs a digital signal with a duty cycle of 0.

[0165] Thus, after the control signal passes through the drive unit, within one cycle, in the first half of the cycle, the first energizing signal output pin outputs the first energizing signal to the first coil, and the first coil receives a positive digital signal at the corresponding positive terminal. In the second half of the cycle, the second energizing signal output pin outputs the first energizing signal to the first coil, and the first coil receives a negative digital signal at the corresponding negative terminal. The digital voltage signal across the first coil is the positive digital signal minus the negative digital signal. Within one cycle, the driving current is an alternating current that changes between positive and negative. The current is positive in the first half of the cycle and negative in the second half, and vice versa.

[0166] The third and fourth power signal output pins output a second power signal to the second coil within one cycle. The digital voltage signal obtained at both ends of the second coil is the same as the first power signal obtained at the first power signal output pin and the second power signal output pin, and the digital voltage signal obtained at both ends of the first coil is obtained in the same way, which will not be described again here.

[0167] In this embodiment, the digital signal output by the control signal output pin of the control unit is a PWM signal. Taking the digital signal output by the control unit as voltage as an example, the PWM1 output by the first control signal output pin and the PWM2 output by the second control signal output pin correspond to the waveforms of the positive and negative digital voltage signals of the first coil.

[0168] In some embodiments, the PWM output by the control signal output pin within a cycle can be described by the duty cycle. Taking PWM1 output by the first control signal output pin as an example, and PWM1 being a digital voltage signal, it can be understood that PWM1 includes the control signal output by the first control signal output pin in the first half of the cycle and the digital signal with a zero duty cycle output in the second half of the cycle. In the first half of the cycle, a digital voltage signal with a non-zero duty cycle is output. The PWM1 in the first half of the cycle corresponds to the control signal output by the first control signal output pin, and the output in the second half is a digital voltage signal with a zero duty cycle. A cycle can be divided into multiple small cycles, each small cycle corresponding to a duty cycle. The duty cycle within a small cycle is adjustable. The waveform of PWM1 has a duty cycle of 0 in all small cycles in the second half of the cycle, while the duty cycle of all small cycles in the first half of the cycle can be determined according to the waveform of the analog signal required by the first coil, i.e., the waveform of the alternating current.

[0169] If the waveform of the analog signal required by the first coil is a sine wave, then the parameters of the sine wave in the first half of the cycle are obtained to obtain the duty cycle of all small cycles of PWM1 in the first half of the cycle, thereby obtaining the waveform of PWM1 in the first half of the cycle. Similarly, for PWM2, the parameters of the sine wave in the second half of the cycle are obtained to obtain the duty cycle of all small cycles of PWM2 in the second half of the cycle, thereby obtaining the waveform of PWM2 in the second half of the cycle.

[0170] Understandably, the waveform of the analog signal required by the first coil can be confirmed through calibration parameters. At the same time, if the light homogenizer does not have a calibration unit, it can be determined through preset parameters.

[0171] Of course, the sinusoidal waveform proposed in this embodiment is illustrative. In other embodiments, it can be other waveforms, such as trapezoidal waves, etc., depending on the requirements of the laser projection device. No specific limitation is made here. For the sinusoidal waveform, it can be obtained by dividing one period into as many small periods as possible, so that the analog voltage waveform obtained by the control signals of PWM1 and PWM2 acting on the first coil after being amplified by the drive unit or the control signals of PWM3 and PWM4 acting on the second coil is as close as possible to the sinusoidal waveform. Of course, in other embodiments, depending on the waveform of the required analog signal, the number of small periods and the duty cycle of one period are also different. It can be understood that the division of small periods and the value of the duty cycle in each small period in the waveform corresponding to the PWM signal can be adjusted, so as to determine the waveform of the corresponding analog signal.

[0172] In some embodiments, the output frequency range of the first control signal output pin and the second control signal output pin can be realized as a motion frequency of 90 to 130 Hz. If each cycle contains 200 small cycles of PWM with adjustable duty cycle, the frequency range of the driving small cycles is 18 to 26 kHz. Of course, this is an example, and in other embodiments, other parameters may be used, which are not specifically limited here.

[0173] In some embodiments, taking a trapezoidal wave as an example, the first half of the cycle of the control signal output by the first control signal output pin is divided into three stages in chronological order. In the first stage, the duty cycle of the digital signal output by the first control signal output pin increases. In the middle stage, the duty cycle of the digital signal output by the first control signal output pin remains unchanged. In the last stage, the duty cycle of the digital signal output by the first control signal output pin decreases. Thus, in the first half of the cycle, the analog voltage waveform input to the first coil is a half-trapezoidal wave. Similarly, the second control signal output pin is divided into three stages. In each of the three stages, the duty cycle of each small cycle increases, then remains unchanged, and finally decreases. Thus, the voltage waveform applied to the first coil is the first energized signal received by the positive terminal of the first coil minus the first energized signal received by the negative terminal of the first coil. Therefore, the analog waveform of the first coil in one cycle is a trapezoidal wave with alternating positive and negative values.

[0174] like Figure 17 The diagram below illustrates the waveform of the digital signal output by the control unit in one embodiment of this application. In this embodiment, the voltage output by the control unit is 3.3V. The digital signal PWM1 output by the first control signal output pin gradually increases its duty cycle from 0 to its maximum during the first half of the cycle (0-180°), corresponding to the first stage (within the previous stage) of the three stages. Figure 18 The diagram shows the first stage corresponding to 1 / 8 of the cycle, the second stage (the middle stage) corresponding to 1 / 8 to 3 / 8 of the cycle, where the duty cycle remains at the maximum value of the first stage, and the third stage (the last stage) corresponding to 3 / 8 to 4 / 8 of the cycle, where the duty cycle drops to 0. The duty cycle of the second stage is the maximum duty cycle of the entire waveform, which determines the amplitude of the uniform light oscillation. The larger the duty cycle, the larger the amplitude, and the smaller the duty cycle, the smaller the amplitude. The PWM1 waveform in the first half of the cycle corresponds to the control signal output by the first control signal output pin, and the PWM1 waveform in the second half of the cycle corresponds to the digital signal with a zero duty cycle output by the first control signal output pin.

[0175] PWM2 corresponds to the negative terminal of the first coil. Since the control unit can only generate positive waveforms, PWM2 is also a positive waveform. Therefore, the waveform of PWM1 in the first half of the cycle is the same as the waveform of PWM2 in the second half of the cycle (180°-360°). However, the phase difference between PWM1 and PWM2 is 180°. The driving voltage waveform on the first coil is the difference between the waveforms of the first energized signals of the positive and negative terminals of the first coil. In this way, the subtraction of the positive and negative terminals of the first coil can generate a negative driving voltage waveform. Finally, the current of the driving coil is an alternating positive and negative current, and the waveform of the current is a trapezoidal wave or a sine wave.

[0176] certainly, Figure 18 For example, in other embodiments, instead of dividing half a cycle into four time periods, the first time period corresponds to the first stage, the two middle time periods correspond to the second stage, and the last time period corresponds to the third stage. It is sufficient that there are three stages within the half cycle, and the duty cycle of the first stage increases, the duty cycle of the second stage maintains the maximum value of the first stage, and the duty cycle of the third stage decreases, to obtain a trapezoidal wave.

[0177] The principles of PWM3 and PWM4 can be found in PWM1 and PWM2, and will not be repeated here.

[0178] Understandably, the phase difference between the output of PWM1 and the output of PWM3 is 90°.

[0179] In this embodiment, the voltage level output by the control unit is 3.3V, which needs to be converted by the drive unit to achieve a maximum driving current of 1A. The voltage level is then converted to the 5V required by the first and second coils. At this time, the waveforms of the first energizing signal PWM11 output from the first energizing signal output pin and the first energizing signal PWM22 output from the second energizing signal output pin can be referenced. Figure 18 , Figure 5 This is a schematic diagram of the voltage waveform of the first energized signal shown in an embodiment of this application. After passing through the driving unit, the waveform of PWM11 is completely consistent with the waveform of PWM1 in terms of duty cycle and phase, except that the voltage level is converted to 5V, and it also has the driving capability of large current. The waveform of PWM22 is completely consistent with the waveform of PWM2 in terms of duty cycle and phase, except that the voltage level is converted to 5V, and it also has the driving capability of large current.

[0180] The second energized signal received by the second coil is similar, and will not be elaborated here.

[0181] In this embodiment, Figure 5 The waveform diagram of the analog signal obtained by the first coil after the first energizing signal is shown below. Figure 5 As shown, it is understandable. ​Taking the analog signal applied to the first coil as a voltage signal as an example, the waveform of the analog voltage signal applied to the first coil is the positive voltage X+ minus the negative voltage X-. At a constant temperature, the resistance of the coil can be considered a fixed constant. Therefore, the waveform of the alternating current driving the first coil is similar to, and proportional to, the waveform of the analog voltage signal; that is, the shape of the alternating current waveform of the first coil is similar to, and proportional to, the analog voltage signal waveform. ​ Same (numerical values ​​may differ).

[0182] In this embodiment, the motion trajectory of the light homogenizer is circular or elliptical. The radius of the circular or elliptical trajectory is determined by the duty cycle of the waveform in the output control signal. By changing the duty cycle, the amplitude of the light homogenizer's motion can be changed. The larger the duty cycle, the larger the area of ​​the circular or elliptical trajectory of the light homogenizer. The smaller the duty cycle, the smaller the amplitude, and the smaller the area of ​​the circular or elliptical trajectory (the smaller the radius of the circle or the smaller the minor axis of the ellipse). Thus, in this embodiment, the control signal is amplified by the drive unit to obtain a first energizing signal and a second energizing signal to drive the light homogenizer. The first energizing signal and the second energizing signal act on the first coil and the second coil to obtain an alternating current driving the two coils. The waveform of this alternating current can be a trapezoidal wave or a sine wave. Similarly, based on the required waveform of the alternating current, a corresponding digital signal can be generated by the control unit so that the applied alternating current can satisfy the corresponding waveform, thereby making the motion trajectory of the alternating current waveform circular or elliptical, improving the homogenizing and speckle elimination effect of the light homogenizer.

[0183] In some embodiments, for the laser projection device in the above embodiments, the driving module is configured to: send a first energizing signal to the first coil through the first energizing signal output pin in the first half of the cycle during the period of one revolution of the light homogenizer, and send a first energizing signal to the first coil through the second energizing signal output pin in the second half of the cycle, so as to energize the first coil.

[0184] Within one revolution of the light-monitoring component, a second energizing signal is sent to the second coil through the third energizing signal output pin in the first half of the cycle, and a first energizing signal is sent to the second coil through the fourth energizing signal output pin in the second half of the cycle, so as to energize the second coil.

[0185] The phase difference between the first energized signal sent by the first energized signal output pin and the second energized signal sent by the third energized signal output pin is one-quarter of a cycle. The phase difference between the first energized signal sent by the second energized signal output pin and the second energized signal sent by the fourth energized signal output pin is one-quarter of a cycle. The light-diffusing element moves under the magnetic force generated after the first coil and / or the second coil are energized.

[0186] Understandably, in this embodiment, the control unit in the drive module outputs a control signal, and the drive unit amplifies the control signal to obtain a first energizing signal and a second energizing signal. The two energizing signal output pins connected to a coil alternately output energizing signals within half a cycle, thereby realizing the change in the direction of the current in the coil.

[0187] In other embodiments, the light-diffusing device includes a calibration unit, which is configured with calibration parameters for the light-diffusing device; the driving module is further configured to: read the calibration parameters in the calibration unit; and generate a first energizing signal and a second energizing signal based on the calibration parameters, so that after the first coil receives the first energizing signal and / or the second coil receives the second energizing signal and is energized, the motion trajectory of the light-diffusing device conforms to the calibration parameters.

[0188] When the light homogenizer has a calibration function, the waveform of the AC current in the coil can be determined by obtaining the calibration parameters in the calibration unit. Specifically, the calibration parameters can be read by the control unit, and a corresponding control signal of the waveform can be issued. The control signal enters the drive unit for amplification and processing, thereby obtaining the trapezoidal or sine AC current of the drive coil.

[0189] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

[0190] For ease of explanation, the above description has been provided in conjunction with specific embodiments. However, the above exemplary discussion is not intended to be exhaustive or to limit the embodiments to the specific forms disclosed above. Various modifications and variations can be obtained based on the above teachings. The selection and description of the above embodiments are for the purpose of better explaining the principles and practical applications, thereby enabling those skilled in the art to better utilize the embodiments and various different variations of embodiments suitable for specific application considerations.

Claims

1. A laser projection device, characterized in that, The laser projection device includes a light source for providing an illumination beam; An optical engine is disposed in the optical path of the illumination beam and is used to adjust the illumination beam to obtain a projection beam; A lens is used to image the projected beam; wherein, The optical engine includes a light-diffusing device, which is disposed in the optical path of the illumination beam and located between the light source and the lens. The light-diffusing device includes a first coil, a second coil, and a light-diffusing element. The optical engine further includes a driving module, which is connected to the first coil and the second coil. The driving module is used to send a first energizing signal to the first coil to energize the first coil and a second energizing signal to the second coil to energize the second coil. The light homogenizer moves under the magnetic force generated after the first coil and / or the second coil are energized. The phase difference between the first energized signal and the second energized signal is one-quarter of a cycle.

2. The laser projection device according to claim 1, characterized in that, The first coil includes a first positive terminal and a first negative terminal. The first positive terminal receives the first energizing signal in the first half of the cycle, and the first negative terminal receives the first energizing signal in the second half of the cycle. The second coil includes a second positive terminal and a second negative terminal. The second positive terminal receives the second energizing signal in the first half of the cycle, and the second negative terminal receives the first energizing signal in the second half of the cycle.

3. The laser projection device according to claim 2, characterized in that, The first half of the period of the first energized signal received by the first positive terminal is divided into three stages according to time sequence. In the first stage, the duty cycle of the first energized signal received by the first positive terminal increases. In the middle stage, the duty cycle of the first energized signal received by the first positive terminal remains unchanged. In the last stage, the duty cycle of the first energized signal received by the first positive terminal decreases.

4. The laser projection device according to claim 1, characterized in that, The drive module includes a control unit and a drive unit. The control unit is connected to the drive unit. The drive unit receives control signals from the control unit and amplifies the control signals to generate the first power-on signal and the second power-on signal.

5. The laser projection device according to claim 4, characterized in that, The light-diffusing device includes a calibration unit, which is configured with calibration parameters for the light-diffusing device; wherein, The control unit is connected to the calibration unit, and the control unit reads the calibration parameters in the calibration unit to generate the control signal.

6. The laser projection device according to claim 5, characterized in that, The calibration unit includes a first communication pin, and the control unit includes a second communication pin. The first communication pin is connected to the second communication pin, and the control unit reads the calibration parameters based on the second communication pin and the first communication pin.

7. The laser projection device according to claim 1, characterized in that, The driving module includes a first power-on signal output pin, a second power-on signal output pin, a third power-on signal output pin, and a fourth power-on signal output pin; The first energizing signal output pin and the second energizing signal output pin are respectively connected to the two ends of the first coil, and are used to output the first energizing signal to the first coil; The third and fourth energizing signal output pins are respectively connected to the two ends of the second coil to output the second energizing signal to the second coil.

8. The laser projection device according to claim 7, characterized in that, The drive module includes a control unit and a drive unit. The control unit includes a first control signal output pin, a second control signal output pin, a third control signal output pin, and a fourth control signal output pin. The drive unit includes a first control signal receiving pin, a second control signal receiving pin, a third control signal receiving pin, and a fourth control signal receiving pin. The drive unit receives the control signal sent by the control unit through the first control signal output pin via the first control signal receiving pin, and amplifies it to output the first power-on signal at the first power-on signal output pin. The drive unit receives the control signal sent by the control unit through the second control signal output pin via the second control signal receiving pin, and amplifies it to output the first power-on signal at the second power-on signal output pin. The drive unit receives the control signal sent by the control unit through the third control signal output pin via the third control signal receiving pin, and amplifies it to output the second power-on signal at the third power-on signal output pin. The drive unit receives the control signal sent by the control unit via the fourth control signal output pin through the fourth control signal receiving pin, and amplifies it to output the second power-on signal through the fourth power-on signal output pin.

9. The laser projection device according to claim 8, characterized in that, The first control signal output pin outputs a control signal during the first half of the cycle, and the second control signal output pin outputs a control signal during the second half of the cycle. The third control signal output pin outputs a control signal during the first half of the cycle, and the fourth control signal output pin outputs a control signal during the second half of the cycle. The phase difference between the control signal output by the first control signal output pin and the control signal output by the third control signal output pin is one-quarter of a cycle, and the phase difference between the control signal output by the second control signal output pin and the control signal output by the fourth control signal output pin is one-quarter of a cycle.

10. The laser projection device according to any one of claims 1-9, characterized in that, The light-diffusing device further includes: Support base; A motion plate, which is fixed to the support base by an elastic device; A magnetic device, which is fixed to the moving plate; The light-diffusing element is fixed on the motion plate, and the first coil and the second coil are both fixed on the support base. The magnetic device is located above the first coil and the second coil. The magnetic force generated by the first coil and / or the second coil after being energized drives the motion plate to move, thereby causing the light-diffusing element to move.

Images