CN113534577A

CN113534577A - Laser projection device

Info

Publication number: CN113534577A
Application number: CN202010313356.6A
Authority: CN
Inventors: 崔荣荣
Original assignee: Qingdao Hisense Laser Display Co Ltd
Current assignee: Qingdao Hisense Laser Display Co Ltd
Priority date: 2020-04-20
Filing date: 2020-04-20
Publication date: 2021-10-22
Anticipated expiration: 2040-04-20
Also published as: CN115427885A; WO2021213101A1; CN113534577B

Abstract

The application discloses projection equipment includes: a light source for emitting a three-color light beam; the light valve is used for modulating and outputting the three-color light beams; the galvanometer is positioned between the light valve and the projection lens and used for changing the position of the light beam output by the light valve under the control of the driving current; the projection lens is used for imaging the light beams at different positions output by the galvanometer; the vibrating mirror comprises a circuit board and an optical mirror surface arranged on the circuit board, and the circuit board is used for driving the optical mirror surface to turn over under the electromagnetic action. The laser projection equipment in the scheme is convenient to realize miniaturization and low noise.

Description

Laser projection device

Technical Field

The present disclosure relates to laser projection technologies, and in particular, to a laser projection apparatus.

Background

At present, in a process of displaying an image to be projected by a projection device, if it is determined that a resolution of the projection device is smaller than a resolution of the image to be projected, the projection device needs to remove a part of pixels in the image to be projected and display the processed image to be projected so as to ensure that the projection device can display the processed image to be projected. However, since the projection device needs to remove some pixels in the image to be projected, the final displayed image is poor.

Therefore, under the condition of being limited by the resolution of the light valve, even if the resolution of the target image to be displayed is higher, the projection display device cannot restore the display.

In a prior art scheme, can increase pixel skew device, for example the galvanometer, vibrate in the position of difference, can let the light beam of its lens of transmission carry out the dislocation stack to carry out the stack of picture, utilize people's eye persistence of vision effect, two at least dislocation stack's pictures can seem a picture, and the definition of picture improves, has realized the promotion of resolution ratio in the visual effect, thereby even if the projection equipment that has the low resolution ratio light valve also can realize the projection of "high resolution ratio" image. However, the installation of the mirror-vibrating component needs to consider the space volume, and also needs to pay attention to the fact that the vibration in the working process of the mirror-vibrating possibly causes the resonance of the shell, so that noise is brought, and the user experience is reduced.

Disclosure of Invention

The embodiment of the disclosure provides a laser projection device, which can realize high-definition images by using a vibrating mirror and is beneficial to realizing low noise and miniaturization of the device.

In order to realize the technical purpose, the following technical scheme is adopted:

a laser projection device comprising: a light source for emitting a three-color light beam; the light valve is used for modulating and outputting the three-color light beams; the galvanometer is positioned between the light valve and the projection lens and used for changing the position of the light beam output by the light valve under the control of the driving current; the projection lens is used for imaging the light beams at different positions output by the galvanometer; the vibrating mirror comprises a circuit board and an optical mirror surface arranged on the circuit board, wherein the circuit board is used for driving the optical mirror surface to turn over under the electromagnetic action.

The beneficial effects brought by the technical scheme provided by the embodiment of the disclosure at least comprise:

the utility model provides a pair of projection equipment, set up the galvanometer between light valve and projection lens, the light beam that realizes different moments through the vibration of galvanometer takes place the displacement when the space is transmitted, realize the dislocation stack when the light beam is through projection lens formation of image, can realize the improvement of image definition, thereby improve the quality of projection image, simultaneously, because the galvanometer comprises circuit board and the optical mirror surface that sets up on the circuit board, the structure presents the slabby, be convenient for at projection equipment internally mounted, and realize low noise, do benefit to and realize projection equipment's miniaturization and low noise purpose.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.

Fig. 1 is a schematic diagram of an optical path architecture of a projection apparatus provided in an embodiment of the present disclosure;

fig. 2 is a schematic hardware structure diagram of a projection apparatus provided in an embodiment of the present disclosure;

fig. 3 is a flowchart of a projection display method provided by an embodiment of the present disclosure;

FIG. 4 is a schematic diagram of a first frame sub-image displayed on a projection screen when a galvanometer is in an original position according to an embodiment of the disclosure;

FIG. 5 is a schematic diagram of a first frame sub-image displayed on a projection screen during deflection of a galvanometer according to an embodiment of the disclosure;

FIG. 6 is a schematic diagram of the deflection position of the galvanometer during rotation of the galvanometer along different axes provided by embodiments of the present disclosure;

FIG. 7 is a schematic diagram of a second frame sub-image displayed on a projection screen during deflection of a galvanometer according to another embodiment of the disclosure;

FIG. 8 is a waveform diagram of a galvanometer drive current for driving the galvanometer in a deflection along a second axis provided by an embodiment of the present disclosure;

FIG. 9 is another waveform of a galvanometer drive current for driving the galvanometer in a deflection along a second axis provided by embodiments of the present disclosure;

FIG. 10 is a schematic diagram of a third frame of sub-images displayed on a projection screen during a further galvanometer deflection provided by an embodiment of the present disclosure;

FIG. 11 is a schematic diagram of a fourth frame of sub-images displayed on a projection screen during deflection of a galvanometer according to another embodiment of the disclosure;

FIG. 12 is a schematic diagram of a first frame sub-image displayed on a projection screen during deflection of a galvanometer according to an embodiment of the disclosure;

FIG. 13 is a schematic structural diagram of a galvanometer provided by an embodiment of the present disclosure;

fig. 14 is a schematic structural diagram of a circuit board in a galvanometer provided by an embodiment of the present disclosure;

FIG. 15 is a schematic structural diagram of an optical mirror in a galvanometer provided by an embodiment of the present disclosure;

FIG. 16 is a schematic diagram of a driven galvanometer deflection provided by an embodiment of the present disclosure;

fig. 17 is a schematic diagram of a driven galvanometer deflected along a fourth direction by using a second axis as a rotation axis according to an embodiment of the disclosure.

Detailed Description

To make the objects, technical solutions and advantages of the present disclosure more apparent, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

The laser projection apparatus shown in fig. 1 includes a light source 30, and the light source 30 may include three color laser chips integrally disposed on a package unit, or three sets of monochromatic laser light emitting units, which can emit red laser light, blue laser light, and green laser light.

The light source 30 may be a laser and a wavelength conversion device, and the wavelength conversion device may be a fluorescent wheel that can be excited to emit fluorescent light. In this example, the light source 30 is exemplified as a three-color laser light source.

And referring to fig. 1, the full color laser projection apparatus further includes a reflective combiner lens 70, a lens assembly 80, a diffusion wheel 90, a light pipe 100, a Total Internal Reflection (TIR) prism 110, a projection lens 120, and a projection screen 130. Wherein the lens assembly 80 comprises a first lens 801, a second lens 802 and a third lens 803.

The three-color laser beams emitted by the light source 30 are combined and output by the reflection light combining lens 70, and then enter the first lens 801 for condensation, are diffused by the diffusion wheel 90 for light uniformization, and are totally reflected by the light guide tube 100 for light uniformization. Wherein the diffusion wheel 90 can achieve speckle reduction by diffusing the uniform light. Then, the blue laser, the red laser and the green laser after being homogenized by the light guide 100 are shaped by the second lens 802 and the third lens 803 in a time sharing manner, and enter the TIR prism 110 for total reflection, and after being incident to the light valve 40, the light valve 40 reflects the light beam and transmits and outputs the light beam through the TIR prism again, at this time, a vibrating mirror arranged between the light valve 40 and the projection lens 120 is driven and controlled to deflect the lens, so that when the light beam reflected by the light valve 40 is transmitted, the light beams at different moments are displaced, further, the light spots are dislocated, and thus the light beams which are alternately dislocated are incident to the projection lens 120, and thus, the phenomenon of picture dislocation and superposition is also formed on the projection picture. Due to the phenomenon of human vision persistence, if the staggered and superposed pictures are related, the information content of the images is increased visually, the definition is improved, and the effect of improving the resolution is achieved.

In the following examples, the projection display process will be described with the laser projection apparatus shown in fig. 1 as an application scenario.

As shown in fig. 2, the projection apparatus may include a display control assembly 10, at least one laser driving assembly 20, a light source 30, a light valve 40, a galvanometer driving assembly 50, and a galvanometer 60, wherein the light source 30 may include at least one set of lasers in one-to-one correspondence with the at least one laser driving assembly 20. The at least one means one or more, and the plurality means two or more. The at least one group refers to one or more groups, the multiple groups refers to two or more groups, and each group of lasers may include one or more lasers.

The display control module 10 may be a Digital Light Processing Chip (DLPC). By way of example, the display control assembly 10 may be a DLPC 6540. The light source 30 may be a laser light source, which may include a blue laser, a red laser, and a green laser. The light valve 40 may be a digital micro-mirror device (DMD). The galvanometer 60 may be used to shift sub-images of different frames to different positions of the projection screen, so as to realize the superimposed display of the sub-images of the frames, thereby achieving the effect of extending the resolution of the projection device. Alternatively, the galvanometer 60 may have four deflection positions, i.e., the galvanometer 60 may deflect the sub-image to four different positions on the projection screen. It is also possible that the galvanometer 60 is switched between two positions, i.e. has two deflection positions.

The display control component 10 is configured to obtain multiple frames of sub-images, where the multiple frames of sub-images are obtained by decomposing a target image to be projected, a resolution of the target image is greater than a resolution of the light valve, and a resolution of each frame of sub-image is not greater than the resolution of the light valve.

The display control component 10 is connected to each laser driving component 20, and is configured to output at least one enable signal corresponding to three primary colors of each frame of sub-image one to one, transmit the at least one enable signal to the corresponding laser driving component 20, output at least one laser current control signal corresponding to three primary colors of each frame of sub-image one to one, and transmit the at least one laser current control signal to the corresponding laser driving component 20.

Each laser drive assembly 20 is connected to a corresponding group of lasers for providing a corresponding laser drive current to the laser to which it is connected in response to the received enable signal and laser current control signal.

Each laser is adapted to emit laser light driven by a laser drive current provided by a corresponding laser drive assembly 20.

The display control assembly 10 is further configured to control the light valve 40 to turn over according to the primary color gradation values of the pixels in each frame of sub-images in the process that the three primary colors emitted by the laser are sequentially irradiated to the light valve 40, so as to sequentially project multiple frames of sub-images onto the projection screen through the projection lens.

The display control component 10 is further configured to transmit a galvanometer current control signal corresponding to the sub-image to the galvanometer driving component during the process of displaying each frame of sub-image by projection.

The galvanometer driving component 50 is used for providing galvanometer driving current to the galvanometer 60 under the control of a galvanometer current control signal so as to drive the galvanometer 60 to deflect. And the galvanometer current control signals corresponding to the sub-images of different frames are different.

In the laser projection apparatus shown in fig. 1, a galvanometer structure as shown in fig. 13 to 15 is applied. Referring to fig. 13, the galvanometer 60 may include a circuit board 61 and an optical mirror 62 that are stacked. Referring to fig. 14, the circuit board 61 may include a substrate 610 and a plurality of coil groups 611. For example, two coil groups 611 are shown in fig. 14. The substrate 610 has a first hollow-out region L0 and a first edge region L1 surrounding the first hollow-out region L0, the plurality of coil sets 611 are located in the first edge region L1, and the galvanometer driving component 50 is configured to provide a galvanometer driving current to each coil set 611 to drive the optical mirror 62 to deflect. The first hollowed-out area L0 is an area through which the light beam totally reflected by the TIR lens 110 passes.

In one embodiment, the substrate 610 may be a Printed Circuit Board (PCB), the flatness accuracy of the substrate 610 may be 0.1 millimeter (mm), and the flatness accuracy of the substrate 610 completely meets the requirement of the galvanometer on the flatness accuracy of the fixed support plate, so the substrate 610 may be directly used as the support plate of the galvanometer without adding an additional support plate to the galvanometer, thereby simplifying the overall structure of the galvanometer and reducing the manufacturing cost.

Each coil group may include one or more coils, and the number of turns of each coil may be n0 turns, where n0 is a positive integer greater than 0. And the number of turns, the diameter of the wire, the wiring shape and the number of wiring layers of each coil can be designed according to actual requirements.

Referring to fig. 15, the optical mirror 62 may include a carrier plate 620, an optical glass 621 located on one side of the carrier plate 620 close to the circuit board 61, and a plurality of magnetic assemblies 622, where each magnetic assembly 622 corresponds to one coil assembly 611. For example, two magnetic assemblies 622 corresponding to the two coil sets 611 in fig. 14 are shown in fig. 15. Wherein, each coil group 611 is used to interact with the magnetic component 622 under the driving of the driving current to drive the optical glass 621 to rotate along one rotation axis, and the rotation axes corresponding to the different coil groups 611 intersect. Alternatively, the material of the carrier plate 620 may be a metal material. The polarities of the ends of the magnetic elements 622 close to the carrier plate may all be the same, and correspondingly, the polarities of the ends of the magnetic elements 622 far away from the carrier plate are also all the same. For example, if the polarities of the ends of the magnetic elements 622 close to the carrier are all N-poles, the polarities of the ends of the magnetic elements 622 far away from the carrier are all S-poles. If the polarities of the ends of the magnetic elements 622 close to the carrier are all S-poles, the polarities of the ends of the magnetic elements 622 far away from the carrier are all N-poles.

The carrier plate 620 has a second hollow area L2 and a second edge area L3 surrounding the second hollow area L2. The optical glass 621 covers the second hollow-out region L2, the plurality of magnetic elements 622 are located in the second edge region L3, and the orthographic projection of the optical glass 621 on the substrate 610 and the orthographic projection of the second hollow-out region L2 on the substrate 610 both overlap the first hollow-out region L0, and each coil group 611 overlaps the orthographic projection of the corresponding one of the magnetic elements 622 on the substrate 610. Optionally, a center point of an orthographic projection of the optical glass 621 on the substrate 610 and a center point of an orthographic projection of the second hollow-out region L2 on the substrate 610 both overlap with a center point of the first hollow-out region L0. The first and second hollow areas L0 and L1 may be referred to as clear apertures.

Alternatively, referring to fig. 15, the shape of the optical glass 621 is centrosymmetric, for example, the optical glass 621 may be a square, and the rotation axis may be the first axis X or the second axis Y. The first axis X is parallel to one side of the optical glass 621, and the second axis Y is parallel to the other side of the optical glass 621. The first axis X and the second axis Y may be perpendicular. Alternatively, the optical glass 621 may be circular or rectangular.

Illustratively, the transmittance of the optical glass 621 is greater than or equal to 98%, and the thickness of the optical glass 621 may range from (2.05mm, 1.95mm), and the refractive index of the optical glass 621 may be 1.523 for light having a wavelength of 590 nanometers (nm).

Alternatively, referring to fig. 14, each coil group 611 may include a first coil having one end connected to a positive electrode and the other end connected to one end of a second coil having the other end connected to a negative electrode. Referring to fig. 15, each of the magnetic assemblies 622 can include a first magnetic assembly 6220 and a second magnetic assembly 6221.

Referring to fig. 14 and 15, the first coil is disposed around a first central region R1, the first central region R1 overlapping an orthographic projection of the first magnetic element 6220 on the substrate 610. The second coil is disposed around a second central region R2, the second central region R2 overlapping with an orthographic projection of the second magnetic element 6221 on the substrate 610.

By way of example, the first and second

magnetic assemblies

6220, 6221 may each be a bar-type magnetic assembly. Accordingly, the first and second central regions R1 and R2 may be stripe-shaped regions.

Referring to fig. 14 and 15, the first hollowed-out area L0 and the second hollowed-out area L2 may be both central symmetric areas, for example, may be both squares, the plurality of coil sets 622 may include a first coil set and a second coil set, and the optical mirror 62 may include two magnetic assemblies 622. The first coil and the second coil in each coil group 611 are disposed at two sides of the first hollow-out area L0, and the coils in different coil groups 611 are located at different sides of the first hollow-out area L0. Optionally, the first hollowed-out area L0 and the second hollowed-out area L2 may be both rectangular or circular. The first hollow-out area L0, the second hollow-out area L2 and the optical glass 621 have the same shape. Alternatively, the first shaft and the second shaft may be axes of the first hollow area, that is, two coils in the first coil group are oppositely arranged on two sides of the first shaft, and two coils in the second coil group are oppositely arranged on two sides of the second shaft.

For example, referring to fig. 14, the central region surrounded by each coil in the first coil group 622 on the substrate 610 is parallel to the first axis X. For example, the first coil group 622 includes a first coil C0 and a second coil C1, and the first coil C0 and the second coil C1 are oppositely disposed at both sides of the long side of the first hollow area L0. One end of the first coil C0 is connected to the positive electrode AX +, the other end of the first coil C0 is connected to one end of the second coil C1, the other end of the second coil C1 is connected to the negative electrode AX-, and the first coil C0 and the second coil C1 may be connected in series to form a current path.

The central area surrounded by each coil in the second coil group 622 on the substrate 610 is parallel to the second axis Y. For example, the second coil group 622 includes a first coil B0 and a second coil B1, and the first coil B0 and the second coil B1 are oppositely disposed at both sides of a short side of the first hollow area L0. One end of the first coil B0 is connected to the positive electrode AY +, the other end of the first coil B0 is connected to one end of the second coil B1, the other end of the second coil B1 is connected to the negative electrode AY-, and the first coil B0 and the second coil B1 may be connected in series to form another current channel.

Optionally, the substrate 610 may include a first sub-substrate and a second sub-substrate, each layer of sub-substrate is provided with a first coil group and a second coil group, and the coils on the sub-substrates of different layers may be connected through vias. One end of the first coil in the first sub-substrate is connected with the positive electrode, and the other end of the first coil in the first sub-substrate can be connected with one end of the first coil on the second sub-substrate through the first via hole. The other end of the first coil positioned on the second sub-substrate is connected with one end of the second coil positioned on the second sub-substrate, the other end of the second coil positioned on the second sub-substrate can be connected with one end of the second coil positioned on the first sub-substrate through the second through hole, and the other end of the second coil positioned on the first sub-substrate is connected with the negative electrode.

In an embodiment of the disclosure, the first coil on the first sub-substrate, the first coil on the second sub-substrate, the second coil on the first sub-substrate, and the second coil on the second sub-substrate may be combined into one continuous coil. Referring to fig. 14, taking the first coil C0 and the second coil C1 as an example, the top layer wiring of each coil on the first sub-substrate is represented by a solid line and the bottom layer wiring is represented by a dotted line. The coil is led out from the pin 3 of the socket 09 on the first sub-substrate, and after being wound around the first center region R1 counterclockwise by n0 turns, the first coil C0 is formed on the first sub-substrate. The coil is then replaced from the first submount to the second submount through the first via 01. And continues to wind n0 turns counterclockwise around the first central region R1 on the second sub substrate, forming the first coil C0 on the second sub substrate. Thereafter, the coil is continuously wound clockwise around the second center region R2 on the second sub substrate by n0 turns, and the second coil C1 is formed on the second sub substrate. Thereafter, the coil is switched from the second sub-substrate to the first sub-substrate through the second via hole 02, and wound clockwise n0 turns around the second center region R2 of the first sub-substrate, forming the second coil C1 on the first sub-substrate. Finally the coil is connected to pin 4 of the socket 09. The socket 09 is connected to the galvanometer driving assembly 50, and the galvanometer driving assembly 50 can provide a galvanometer driving current to the first coil C0 and the second coil C1 through pins of the socket 09.

In the embodiment of the present disclosure, each turn of each coil is printed on the substrate of the PCB in a gapped winding manner, that is, each coil group 611 is wound by routing on the substrate 610, thereby simplifying the process and greatly reducing the cost. And because a space stereoscopic gap exists between any two adjacent turns of coils, after the coil group is electrified, the coil winding mode is beneficial to the heat dissipation of the coils in the coil group, so that the condition that the deflection of the galvanometer is influenced due to overhigh temperature of the coils is avoided, and the deflection precision and the deflection reliability of the galvanometer are ensured. And because the wiring material of the substrate 610 is copper, and the copper is laid on each layer of non-wiring area of the substrate and grounded, and effective heat dissipation is realized, after the coil assembly 611 is electrified, the substrate 610 can quickly dissipate heat in a large area, so that the deflection precision and reliability of the galvanometer are further ensured.

Optionally, the substrate 610 may include an even number of layers of sub-substrates, for example, the substrate 610 may include 2 layers of sub-substrates, 4 layers of sub-substrates, or 8 layers of sub-substrates. The number of layers of the sub-substrate is not limited in the embodiments of the present disclosure. The number of turns of the coil can be increased by increasing the number of layers of the sub-substrates, and the magnetic field between the corresponding magnetic assemblies is enhanced, so that the magnetic force for turning the optical mirror surface is increased. Or the number of the layers of the sub-substrates can be increased by reducing the size of each sub-substrate to ensure that the number of turns of the coil is not changed, and further ensure that the magnetic force generated by the magnetic field between the magnetic assemblies corresponding to the coil is not changed.

Alternatively, referring to fig. 14 and 15, the second edge region L3 may include four corner regions 03, and the circuit board 61 may further include four elastic pads, namely, an elastic pad G1, an elastic pad G2, an elastic pad G3, and an elastic pad G4, disposed on the substrate 610. Each of the elastic pads is adapted to be fixedly connected to one of the corner regions 03 of the second edge region L3, and an orthogonal projection of each of the elastic pads on the substrate 610 overlaps an orthogonal projection of one of the corner regions 03 of the second edge region L3 on the substrate 610. Illustratively, each of the resilient pads may be affixed to a top corner region 03 of the second edge region L3.

Alternatively, each of the resilient pads may be triangular, and each of the corner regions 03 is a triangular region, and the size of each of the resilient pads is the same as the size of a corresponding one of the corner regions 03. As an example, each of the elastic pads may be an equilateral triangle, and correspondingly, each of the corner regions 03 may be an equilateral triangle region. The accuracy of the flatness of each of the elastic pieces is greater than or equal to 0.1mm, and each of the elastic pieces has a thickness, whereby the optical mirror surface 62 can be supported, and in addition, in order to avoid scratching the hand during the assembly, the three corners of the equilateral triangle can be subjected to arc treatment.

Optionally, referring to fig. 15, a plurality of third hollow-out regions L4 are further disposed in the second edge region L3, and the plurality of third hollow-out regions L4 surround the second hollow-out region L2. And a connecting shaft 04 exists between any two adjacent third hollow-out areas L4, that is, there is no communication between any two adjacent third hollow-out areas L4, so as to form the optical mirror 62 rotating around the first axis X and the second axis Y as a rotating axis. For example, the plurality of third hollow areas L4 may include four third hollow areas L4, thereby forming an edge sub-area 05 on the second edge area L3. By providing a plurality of third hollow-out regions in the second edge region, the weight of the optical mirror surface can be reduced.

Optionally, referring to fig. 14 and fig. 15, an orthographic projection of the optical glass 621 on the substrate 610 and an orthographic projection of the second hollow-out area L2 on the substrate 610 are both located in the first hollow-out area L0, and the orthographic projection of the optical glass 621 on the substrate 610 covers an orthographic projection of the second hollow-out area L2 on the substrate 610. Optionally, a center point of an orthographic projection of the optical glass 621 on the substrate 610 and a center point of an orthographic projection of the second hollow-out region L2 on the substrate 610 are both located in the first hollow-out region L0 and both coincide with a center point of the first hollow-out region L0.

In the embodiment of the disclosure, the size of the first hollow-out area L0 is determined by the size of the light spot in the light path of the projection apparatus, that is, the size of the light after being totally reflected by the TIR lens 110. The size of the first hollow-out region L0 is greater than the size of the light spot, and the size of the first hollow-out region L0 is greater than the size of the optical glass 621, so as to ensure that the light totally reflected by the TIR lens 110 can be completely projected onto the projection screen without loss of brightness. The dashed area 051 shown in fig. 15 is the same as the first hollowed-out area L0 in size.

The size of the optical glass 621 is larger than that of the second hollow-out area L2, so as to ensure that the optical glass 621 can cover the second hollow-out area L2. For example, the size of the optical glass 621 may be 23mm × 23mm, the size of the first hollowed-out area L0 may be 24mm × 24mm, and the size of the second hollowed-out area L2 may be 21mm × 21 mm.

Referring to fig. 13, 14 and 15, in the process of forming the galvanometer 60, the optical glass 621 is firstly adhered to the second edge area L3 of the carrier plate 620, so that the optical glass 621 covers the second hollowed-out area L2. The first and second

magnetic elements

6220 and 6221 in each magnetic element 622 are then bonded to two sides of the second hollow-out region L2, and different magnetic elements are located on different sides of the second hollow-out region L2, so as to obtain the optical mirror 62. Then, the elastic pad G1, the elastic pad G2, the elastic pad G3, and the elastic pad G4 in the substrate were attached to the corresponding one of the corner regions 03 of the optical mirror surface 62, thereby obtaining the galvanometer 60.

Optionally, the optical mirror surface 62 of the galvanometer 60 is located at a side close to the light valve 40, that is, the supporting plate 620 of the optical mirror surface 62 is located at a side close to the light valve 40, and since the plate surface of the supporting plate 620 is made of a smooth mirror surface material, the smooth mirror surface side is close to the light valve side. When the optical mirror 62 is not deflected, that is, when the mirror surface of the optical mirror 62 is parallel to the horizontal plane, the carrier plate 620 can reflect the light irradiated onto the carrier plate 620, thereby facilitating the heat dissipation of the entire optical mirror 62, reducing the temperature of the substrate, and preventing the vibrating mirror from being damaged due to excessive heat absorption.

Referring to fig. 14, the first edge region L1 may further include a plurality of through holes for fixing the substrate 61 to a bracket of the projection apparatus, and thus the galvanometer 60, by using a material such as screws or shock absorbers. For example, the plurality of through holes are at least three, and may include four through holes, i.e., a through hole S1, a through hole S2, a through hole S3, and a through hole S4, each of which may be a screw hole.

The size and the volume of the mirror that shakes that this disclosed embodiment provided are less, are favorable to projection equipment's miniaturized design, and above-mentioned mirror structure that shakes presents platelike, also be convenient for when the installation is fixed the casing to be connected through the many places of at least three mounting and shells inner wall, and this kind of fixed connection mode can be with the vibration of the mirror that shakes to the transmission of a plurality of directions to the amplitude in each direction all can be less, can greatly reduced noise, for example can be as low as 20 decibels (20dB) when concrete application.

In the embodiment of the present disclosure, referring to fig. 14, the substrate 61 is further provided with an Electrically Erasable Programmable Read Only Memory (EEPROM) 06 and a Temperature Sensor (TS) 07. The EEPROM 06 and TS 07 are connected via an I2C socket 09. After the coil is powered on, the TS 07 can detect the ambient temperature of the coil assembly on the substrate in real time and send the ambient temperature to the display control component 10. The display control assembly 10, upon receiving the ambient temperature, may detect whether the ambient temperature is within a temperature range. If this ambient temperature is not in temperature range, it is unusual to show the ambient temperature of this coil assembly and loading board, and this ambient temperature can all cause the influence to the electric current of coil assembly and the deformation of loading board promptly, because expend with heat and contract with cold can influence the deflection of loading board to influence the precision that the galvanometer deflected. The display control component 10 may send a correction parameter acquisition instruction to the EEPROM 06, where the correction parameter acquisition instruction carries the ambient temperature. After receiving the ambient temperature, the EEPROM 06 may obtain a correction parameter corresponding to the ambient temperature from a pre-stored correspondence between the temperature and the correction parameter, and send the obtained correction parameter to the display control component 10. The display control component 10 can adjust the galvanometer current control signal transmitted to the galvanometer driving component 50 according to the correction parameter, and further adjust the galvanometer driving current provided by the galvanometer driving component 50 to the galvanometer, so as to eliminate the influence of temperature on the deflection precision of the galvanometer in time. The correction parameter may be an amplitude of the galvanometer current control signal.

The following describes a driving process of the galvanometer 60 by taking an example in which the galvanometer driving unit 50 drives the galvanometer 60 and deflects in the third direction and the fourth direction about the second axis Y as a rotation axis. For convenience of explanation, the magnetic member 622 and the carrier plate to which the optical glass is attached are shown separately in fig. 16. Referring to fig. 16, the first magnetic element 6220 and the second magnetic element 6221 are disposed in the optical mirror 62 with both N-poles at the ends near the coils.

When the galvanometer drive assembly 50 is not supplying galvanometer drive current to the galvanometer 60, the optical glass 621 is at position 004. When the galvanometer driving assembly 50 supplies a galvanometer driving current in a forward direction to the second coil group for driving the galvanometer to rotate around the second shaft as a rotating shaft, for example, when the galvanometer driving current in the forward direction is supplied to the first coil B0 and the second coil B1 shown in fig. 16, that is, the galvanometer driving current flows in from the pin 5 of the socket 09 and flows out from the pin 6 (the pin 5 is a positive electrode AY + of the current and the pin 6 is a negative electrode AY-), the first coil B0 and the second coil B1 both generate magnetic fields, which are similar to the magnetic field of the magnetic assembly 622 and generate an N pole and an S pole. According to the right-hand screw rule, the coil is held by the right hand, the bending direction of the four fingers of the right hand is consistent with the direction of the current, and the end pointed by the thumb of the right hand is the N pole of the first coil B0, i.e. the side of the first coil B0 close to the optical mirror 62 is the N pole, and the side of the first coil B0 far away from the optical mirror 62 is the S pole. According to the right-hand spiral rule and the direction of the current of the second coil B1, it can be obtained that the side of the second coil B1 close to the optical mirror 62 is the S pole, and the side of the second coil B1 far from the optical mirror 62 is the N pole.

Referring to fig. 16, since the side of the first coil B0 close to the optical mirror 62 is N-pole, and the first magnetic element 6220 corresponding to the first coil B0 is N-pole, a repulsive force is generated between the first coil B0 and the first magnetic element 6220. Since the first coil B0 is fixed to the base plate 61 and the base plate 61 is fixed to the structural member, the base plate 61 does not move. According to the principle of the acting force and the reacting force, the first magnetic element 6220 is acted upon by an upward force, so that the first magnetic element 6220 drives the optical glass 621 to shift upward. Meanwhile, since the side of the second coil B1 close to the optical mirror 62 is S-pole and the second magnetic element 6221 corresponding to the second coil B1 is N-pole, a mutual attraction force is generated between the second coil B1 and the second magnetic element 6221, so that the second magnetic element 6221 drives the optical glass 621 to shift downward. In this process, the left and right sides of the optical glass 621 are simultaneously subjected to the acting force of the counterclockwise rotation, and under the action of the acting force, the optical glass 621 deflects in the counterclockwise direction with the second axis Y as the rotation axis until the elastic force between the substrate and the carrier plate 620 is balanced, and the optical glass 621 stops rotating and remains unchanged. Thereby, the optical glass 621 is deflected from the position 004 to the position 005 shown in fig. 16, so that the shift of the light ray, that is, the shift of the light spot, and further the shift of the position of the image to be displayed on the projection screen are realized.

When the galvanometer driving assembly 50 supplies a mirror driving current in the opposite direction to the second coil group for driving the galvanometer to rotate about the second axis Y, for example, when the mirror driving current in the opposite direction is supplied to the first coil B0 and the second coil B1 shown in fig. 16, that is, when the mirror driving current flows in from the pin 6 of the socket 09 and flows out from the pin 5 (the pin 6 is a negative electrode AY "of the current, and the pin 5 is a positive electrode AY + of the current). According to the right-hand screw rule and the current direction of the first coil B0, the side of the energized first coil B0 close to the optical mirror 62 is the S-pole, and the side of the first coil B0 away from the optical mirror 62 is the N-pole. An attractive force is generated between the first coil B0 and the first magnetic element 6220, so that the optical glass 621 is driven by the first magnetic element 6220 to deflect downward. Meanwhile, according to the right-hand screw rule and the current direction of the second coil B1, the side of the second coil B1 close to the optical mirror 62 after being electrified is the N pole, the side of the second coil B1 far away from the optical mirror 62 is the S pole, and the second coil B1 and the second magnetic assembly 6222 generate a mutual repulsive force, so that the optical glass 621 is driven by the second magnetic assembly 6222 to be shifted upwards. In this process, the left and right sides of the optical glass 621 are simultaneously subjected to the clockwise rotation force, and under the action of the clockwise rotation force, the optical glass 621 deflects clockwise around the second axis Y as the rotation axis until the elastic force between the substrate and the carrier plate is balanced, and the optical glass 621 stops rotating and remains unchanged. Thereby, the shift of the optical glass 621 from the position 005 shown in fig. 16 to another position is realized, thereby the shift of the light spot from the position 005 to another position is realized, and further the shift of the position of the image to be displayed on the projection screen is realized.

Similarly, the process that the galvanometer driving assembly 50 drives the galvanometer 60 to deflect along the first direction and the second direction along the first axis X as the rotating axis can refer to the process that the galvanometer driving assembly 50 drives the galvanometer to deflect along the third direction and the fourth direction along the second axis Y as the rotating axis, and the details of the embodiment of the disclosure are not repeated again.

In the embodiment of the present disclosure, referring to fig. 17, assuming that the galvanometer 60 deflects by a first angle θ 1 along the third direction (counterclockwise direction) with the second axis Y as the rotation axis, the thickness of the optical glass 621 is h, the refractive index of the optical glass 621 is n, the length of the internal refracted light ray of the optical glass 621 is L, and the refraction angle is a, since the light ray is vertically incident along the direction of the third axis Z, the incident angle of the incident light is equal to the first angle θ 1 according to a right angle relationship. Since the normals on the surface of the optical glass 621 are parallel, if the incident angle of the internal refraction light of the optical glass 621 is also α, the outgoing angle of the outgoing light beam from the optical glass 621 is equal to the incident angle θ 1 according to the refraction theorem, and the outgoing light beam from the optical glass 621 is emitted in the direction of the third axis Z axis in parallel with the incoming light beam.

Referring to fig. 17 (one), when the galvanometer driving assembly 50 does not supply the galvanometer driving current to the galvanometer 60, light is vertically incident along the third axis Z, and the first axis X and the second axis Y of the galvanometer 60 are both perpendicular to the input light. The incident light is directly emitted in a direction perpendicular to the first axis X and the second axis Y. Referring to fig. 17 (ii), when the galvanometer 60 is deflected counterclockwise by the first angle θ 1 with the second axis Y as the rotation axis, the outgoing light is shifted by a distance d1 in the positive direction of the first axis X as compared with the state of the galvanometer 60 shown in fig. 17 (i), and the distance d1 is the distance by which the pixels in the target image to be projected are shifted on the projection screen.

Assuming that an angle between the internal refracted light of the optical glass 621 and the Z axis is β and a refraction angle is α, and the oscillating mirror 60 is deflected counterclockwise by a first angle θ 1 with the second axis Y as a rotation axis, β ═ θ 1- α, a refractive index

Wherein the length of the light refracted inside the optical glass 621

The

Namely, it is

As can be seen from the formula, the offset distance d1 of the pixel is only related to the deflection angle θ 1 of the galvanometer 60, the refractive index n of the optical glass 621 and the thickness h of the optical glass 621. After the galvanometer assembly is completed, the refractive index n and the thickness h of the optical glass 621 are determined values, so that the offset distance d1 of the pixel is changed mainly with the change of the deflection angle of the galvanometer.

For example, if the edge length of a pixel in an image finally projected and displayed by a 2K-resolution light valve is 5.4 micrometers (um), to realize a 4K-resolution image display, the galvanometer offset distance d1 is equal to one half × the edge length of the pixel at each time, i.e., d1 is 2.7 um.

In the embodiment of the present disclosure, the display control module 10 sends a galvanometer current control signal to the galvanometer driving module 50, and the galvanometer driving module 50 provides a galvanometer driving current to the galvanometer 60 to drive the galvanometer to deflect along the first direction or the second direction with the first axis X as a rotation axis, or to drive the galvanometer 60 to deflect along the third direction or the fourth direction with the second axis Y as a rotation axis. I.e. the deflection of the galvanometer, has four cases, the principle of which is the same.

And, in the disclosed embodiment, referring to fig. 2, if the projection device is a projection television, the projection device may further include a power supply 150, a start control component 160, and a program storage component 170. The main control chip 00 is connected to the start control module 160 and the display control module 10, the power supply 150 is connected to the laser driving module 20, and the program storage module 170 is connected to the display control module 10.

The main control chip 00 sends a start command to the start control module 160, the start control module 160 starts to operate after receiving the start command, and outputs 1.1 volt (V), 1.8V, 3.3V, 2.5V and 5V to the display control module in sequence according to the power-on sequence of the start control module 160 to supply power to the display control module 10. After the power supply voltage and the timing are correct, the start control module 160 sends a power sense (power sense) signal and a power good (PWRGOOD) signal to the display control module 10, and after receiving the two control signals, the display control module 10 reads a program from the external program storage module 170 and initializes the program, and at this time, the whole projection apparatus starts to operate. The display control assembly 10 configures the actuation control assembly 160 via Serial Peripheral Interface (SPI) communication and instructs the actuation control assembly 160 to begin supplying power to the light valve 40. Then, the control module 160 is activated to output 3 voltages to the light valve 40, wherein the Voltage Bias (VBIAS) is 18V, the Voltage Reset (VRST) is-14V, and the Voltage Offset (VOFS) is 10V, and the light valve 40 starts to operate after the voltage of the light valve 40 is normal. The display control circuit 10 transmits the primary color gradation values of the sub-image to the light valve 40 at 594MHz through a high-speed serial interface (HSSI) to implement the sub-image. The power supply in the projection equipment is realized by converting 100-240V alternating current into direct current through a power supply board to supply power to each component.

Fig. 3 is a schematic diagram of a projection display method based on a laser projection apparatus to which the foregoing galvanometer structure is applied, and the projection display method can be applied to the projection apparatus shown in fig. 1 and 2. As shown in fig. 3, the method may include:

step 301, acquiring multiple frames of sub-images.

The multi-frame sub-images are obtained by decomposing a target image to be projected, the resolution of the target image is greater than that of the light valve, and the resolution of each divided frame of sub-image is not greater than that of the light valve, for example, may be equal to that of the light valve.

Alternatively, the resolution of the target image may be M × N, where M is the number of pixels in each row of the target image, and N is the number of pixels in each column. The resolution of the light valve is M1 × N1, M1 is the number of pixels per row in an image that the light valve can project, and N1 is the number of pixels per column. The resolution of each frame of sub-image may be m1 × n1, m1 being the number of pixels per row in each frame of sub-image, n1 being the number of pixels per column. The M, N, M1, N1, M1 and N1 are all positive integers greater than 1, and M is greater than M1, N is greater than N1, M1 is not greater than M1, and N1 is not greater than N1.

For example, the resolution of the target image may be 3840 × 2160, i.e., M is 3840 and N is 2160. The resolution of the light valve may be 1920 × 1080, i.e. M1 is 1920 and N1 is 1080. The resolution of the target image is 1920 × 1080, i.e., m1 is 1920 and n1 is 1080. The resolution of the target image 3840 × 2160 is greater than the resolution of the light valves 1920 × 1080, and the resolution of each sub-image 1920 × 1080 is equal to the resolution of the light valves 1920 × 1080.

In the embodiment of the present disclosure, if the projection apparatus is a projection television, the projection apparatus may further include a main control chip 00, and referring to fig. 2, the display control assembly 10 may be connected to the main control chip 00. When the projection apparatus displays a target image to be projected by projection, the main control chip 00 may decode an image signal of the target image to be projected, and transmit the decoded image signal of the target image to the display control module 10 at a frequency of 60 Hertz (HZ), and accordingly, the display control module 10 may receive the decoded image signal of the target image transmitted by the main control chip 00. Then, the display control component 10 may divide the received decoded image signal of the target image into a plurality of sub-image signals, so as to divide the target image into a plurality of frames of sub-images.

For example, the image signal may be a 4K (i.e., 3840 × 2160) video signal or a digital television signal, and the divided sub-image signal per frame may be a 2K (1920 × 1080) video signal or a digital television signal.

Step 302, at least one enabling signal corresponding to the three primary colors of each frame of sub-image is respectively transmitted to the corresponding laser driving components.

In the disclosed embodiment, the display control assembly 10 is connected to each laser drive assembly 20, as shown in fig. 2. After dividing the target image to be projected into multiple sub-images, the display control component 10 may output at least one enable signal corresponding to the three primary colors of each sub-image, and transmit the at least one enable signal to the corresponding laser driving component 20.

And step 303, respectively transmitting at least one laser current control signal corresponding to the three primary colors of each frame of sub-image to corresponding laser driving components.

In the embodiment of the present disclosure, after dividing the target image to be projected into multiple sub-images, the display control component 10 may further output at least one laser current control signal corresponding to the three primary colors of each sub-image, and transmit the at least one laser current control signal to the corresponding laser driving component 20. The laser current control signal is used to instruct the laser driving component 20 to provide a corresponding laser driving current to the laser connected thereto, so as to drive the laser to emit laser light. The laser current control signal may be a Pulse Width Modulation (PWM) signal.

And step 304, controlling the light valve to turn over according to the primary color gradation values of the pixels in each frame of the sub-images so as to project and display the plurality of frames of the sub-images on the projection screen in sequence.

In the embodiment of the present disclosure, after the laser is controlled to start emitting laser light, the display control component 10 may control the light valve 40 to turn over according to the primary color gradation value of the pixel in each frame of the sub-image, so as to implement the primary color gradation value according to the turning time of the micromirror in the light valve, and form the gray scale corresponding to the three primary colors of the pixel in cooperation with the corresponding color light irradiated onto the light valve, so as to sequentially project and display the multiple frames of the sub-images onto the projection screen, and display the multiple frames of the sub-images onto different positions of the projection screen by controlling the deflection of the galvanometer.

In the disclosed embodiment, the plurality of frames of sub-images may include four frames of sub-images. When the laser emitted by each laser irradiates the light valve 40, the display control component 10 may control the light valve 40 to turn over according to the primary color gradation values of the pixels in each frame of sub-image, so as to sequentially project and display the plurality of frames of sub-images onto the projection screen. For example, the primary color level value may be a Red Green Blue (RGB) level value.

Step 405, in the process of displaying each frame of sub-image by projection, transmitting the galvanometer current control signal of the corresponding sub-image to the galvanometer driving component.

In the embodiment of the present disclosure, in the process of displaying each frame of sub-image by projection, the display control component 10 may transmit a galvanometer current control signal corresponding to one frame of sub-image to the galvanometer driving component 50, where the galvanometer current control signal is used to control the galvanometer driving component 50 to provide a galvanometer driving current to the galvanometer 60 so as to drive the galvanometer 60 to deflect. The current control signals of the galvanometers corresponding to the sub-images of different frames are different, so that the multi-frame sub-images can be projected to different positions on the projection screen, the multi-frame sub-images can be displayed in a superposition mode, and the target image can be displayed on the projection screen.

In the disclosed embodiment, the galvanometer drive current is used to drive the galvanometer 60 to deflect about at least one of a first axis and a second axis, the first axis intersecting the second axis. Alternatively, the first and second axes may be perpendicular. The galvanometer 60 may be quadrilateral, and the first axis may be parallel to one side of the galvanometer 60 and the second axis may be parallel to the other side of the galvanometer 60. For example, the galvanometer 60 may be rectangular and the first and second axes may be perpendicular.

The galvanometer 60 may include a circuit board and an optical mirror surface, which are stacked, and the circuit board may include a first coil group and a second coil group, two coils of the first coil group are oppositely disposed on two sides of a first axis, and two coils of the second coil group are oppositely disposed on two sides of a second axis. The galvanometer current control signal is used for controlling the galvanometer driving component 50 to provide galvanometer driving current for the first coil group so as to drive the optical mirror surface to deflect by taking the first axis as a rotating axis; and/or the galvanometer current control signal is used for controlling the galvanometer driving component 50 to provide galvanometer driving current for the second coil group so as to drive the optical mirror surface to deflect by taking the second shaft as a rotating shaft. That is, the optical mirror may be deflected about a first axis as a rotation axis, or the optical mirror may be deflected about a second axis as a rotation axis, or the optical mirror may be deflected about both the first axis as a rotation axis and the second axis as a rotation axis.

In the process of displaying each frame of sub-image by projection, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the target primary color in the three primary colors, the display control component 10 may transmit a galvanometer current control signal corresponding to the sub-image to the galvanometer driving component 50, where the galvanometer current control signal is used to control the galvanometer driving component to provide a galvanometer driving current to the galvanometer so as to drive the galvanometer 60 to deflect, and then the galvanometer 60 remains unchanged, thereby completing the display of one frame of sub-image. Then, when displaying the next frame of sub-image, the display control component 10 and the galvanometer driving component 50 may drive the galvanometer 60 to deflect again, and so on, thereby implementing the projection display of different frame of sub-images to different positions of the projection screen.

Wherein the target primary light may be a blue primary light. Because human eyes are not sensitive to blue, when the light valve 40 receives the irradiation of blue primary light in the three primary lights, the galvanometer 60 is driven to turn over, and the human eyes can not obviously see the image shift, thereby ensuring the display effect of the image.

Optionally, in the process of displaying the first frame sub-image by projection, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the target primary color in the three primary colors, the display control module 10 may transmit the first galvanometer current control signal to the galvanometer driving module 50. The first galvanometer current control signal is used for controlling the galvanometer driving component 50 to drive the galvanometer 60 to deflect a first angle along a first direction by taking a first axis as a rotating axis, and to drive the galvanometer 60 to deflect the first angle along a third direction by taking a second axis as the rotating axis. Alternatively, the first galvanometer current control signal is used for controlling the galvanometer driving component 50 to drive the galvanometer 60 to deflect by a second angle along the first direction by taking the first axis as a rotating axis.

In the process of displaying the second frame sub-image by projection, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the target primary color in the three primary colors, the display control module 10 may transmit the second galvanometer current control signal to the galvanometer driving module 50. The second galvanometer current control signal is used for controlling the galvanometer driving component 50 to drive the galvanometer 60 to deflect a second angle along a fourth direction by taking the second axis as a rotating axis.

In the process of displaying the third frame of sub-image by projection, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the target primary color in the three primary colors, the display control module 10 may transmit the third galvanometer current control signal to the galvanometer driving module 50. The third galvanometer current control signal is used for controlling the galvanometer driving component 50 to drive the galvanometer 60 to deflect by a second angle along a second direction by taking the first axis as a rotating axis.

When the light valve 40 receives the illumination of the three primary colors in time sequence when the fourth frame sub-image is displayed by projection, and when the light valve 40 receives the illumination of the target primary color in the three primary colors, the display control module 10 may transmit the fourth galvanometer current control signal to the galvanometer driving module 50. The fourth galvanometer current control signal is used for controlling the galvanometer driving component 50 to drive the galvanometer 60 to deflect a second angle along a third direction by taking the second axis as a rotating axis.

Wherein the first direction is opposite to the second direction, and the third direction is opposite to the fourth direction. For example, the first direction and the third direction may both be clockwise. The second and fourth directions may both be counterclockwise directions. The second angle is equal to twice the first angle.

For example, assuming that the first direction and the third direction are clockwise directions and the second direction and the fourth direction are counterclockwise directions, as shown in fig. 4, the first coordinate system may be established with the second axis Y as a horizontal axis and the third axis Z as a vertical axis, and the second coordinate system may be established with the third axis Z as a horizontal axis and the first axis X as a vertical axis. Wherein the third axis Z is perpendicular to the first axis X and the second axis Y, respectively. Referring to (one) and (two) of fig. 4, if the galvanometer drive component 50 does not supply the galvanometer drive current to the galvanometer 60, the galvanometer 60 is in the home position. At this time, the galvanometer 60 is perpendicular to the incident light, i.e., the light is perpendicularly incident to the galvanometer 60 along a direction parallel to the third axis Z. Fig. 4 (three) shows a third coordinate system of the projection screen, where the horizontal axis is X1 and the vertical axis is Y1. When the galvanometer 60 is at the original position, the center pixel in the first frame sub-image may be located at the origin o of the third coordinate system.

The galvanometer 60 shown in fig. 4 is a side view of the galvanometer 60, that is, a side surface of the galvanometer 60, which is perpendicular to the light incident surface of the galvanometer 60.

Referring to fig. 5, in the process of displaying the first frame sub-image a by projection, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the blue primary color in the three primary colors, the display control module 10 may transmit the first galvanometer current control signal to the galvanometer driving module 50, and the galvanometer driving module 50 provides the first galvanometer driving current to the first coil set and the second coil set in the galvanometer 60 respectively. Referring to (one) and (two) of fig. 5, the galvanometer 60 may be driven by the first galvanometer driving current to deflect by a first angle θ 1 in a first direction F1 (i.e., clockwise) about the first axis X, and to deflect by the first angle θ 1 in a third direction F3 (i.e., clockwise) about the second axis Y. It is thereby possible to realize that the center point pixel in the first frame sub-image a is shifted in the negative direction of the X1 axis by the distance d1 and the center point pixel in the first frame sub-image a is shifted in the negative direction of the Y1 axis by the distance d 1. Referring to fig. 5 (two), eventually, the coordinates of the center pixel in the first sub-frame image a in the third coordinate system are (-d 1), i.e., the center pixel in the first sub-frame image a is located at the a position of the third coordinate system.

FIG. 6 is a schematic diagram showing the deflection position of the galvanometer during deflection of the galvanometer about different axes as axes of rotation. The schematic diagram includes a first curve and a second curve, and the first curve represents the deflection distance of the galvanometer relative to the initial position in the deflection process of the galvanometer by taking the first axis X as a rotating axis. The second curve represents the distance the galvanometer is deflected relative to the initial position during deflection about the second axis Y. The horizontal axis of each curve is time t, and the vertical axis is the offset distance s of the galvanometer.

Referring to fig. 6, in the process of projection-displaying the first frame sub-image a, the galvanometer 60 is shifted from the initial position to a negative direction of the second axis Y with the first axis X as a rotation axis, and is deflected from the initial position to the negative direction of the first axis X with the second axis Y as a rotation axis. Then, when the light valve 40 receives the primary color light of green and the primary color light of red in the primary color light in sequence, the galvanometer 60 remains unchanged, i.e., the galvanometer 60 is not deflected until the display of the first frame sub-image a is completed.

FIG. 8 is a waveform diagram of a galvanometer drive current for driving the galvanometer in a deflection along a second axis according to an embodiment of the disclosure. The abscissa of the waveform chart represents time t, and the ordinate represents the magnitude of the drive current I. When the galvanometer driving current changes from positive to negative or from negative to positive, the direction of the galvanometer driving current changes. Referring to fig. 6, 7 and 8, in the process of displaying the second frame sub-image B by projection, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the blue primary color in the three primary colors, the display control module 10 may transmit the second galvanometer current control signal to the galvanometer driving module 50, and the galvanometer driving module 50 provides the second galvanometer driving current to the first coil set of the galvanometer 60 for driving the galvanometer to rotate around the second axis as the rotation axis. The waveform of the second galvanometer driving current can refer to segments t1 and t2 in the current waveform diagram shown in fig. 8, the current in the segment t1 is used for driving the galvanometer 60 to deflect from the negative direction of the first axis X to the positive direction of the first axis X by taking the second axis Y as a rotating axis, and the segment t2 is used for controlling the galvanometer 60 to keep unchanged.

When the second galvanometer driving current is t1, referring to (one) in fig. 7, the galvanometer 60 is driven by the second galvanometer driving current to deflect along the fourth direction F4 (i.e., counterclockwise) by a second angle θ 2 with the second axis Y as the rotation axis, where θ 2 is 2 × θ 1. This is achieved in that the center point pixel in the second frame sub-image B is shifted in the negative direction along the Y1 axis by the positive direction of the distance d2 to Y1, the shift distance d1 of the center point pixel in the negative direction along the X1 axis in the second frame sub-image B is kept constant, and d2 is 2 × d 1. Referring to (two) in fig. 7, eventually, the coordinate of the center point pixel in the second sub-frame image in the third coordinate system is (-d1, d1), i.e., the center point pixel in the second sub-frame image B is located at the B position in the third coordinate system. Referring to fig. 6, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the blue primary color light of the three primary colors, the galvanometer 60 is deflected from the negative direction of the first axis X to the positive direction of the first axis X with the second axis Y as the rotation axis, and does not rotate with the first axis X as the rotation axis, that is, the galvanometer 60 is kept unchanged in the negative direction of the second axis Y. Then, when the light valve 40 receives the primary color light of green and the primary color light of red in the primary color light sequentially, the driving current of the second galvanometer is t2 segment, and at this time, the galvanometer 60 remains unchanged, i.e., the galvanometer 60 is not deflected until the display of the second frame sub-image B is completed.

Referring to fig. 6 and 10, in the process of displaying the third frame of sub-image C by projection, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the blue primary color in the three primary colors, the display control module 10 may transmit the third galvanometer current control signal to the galvanometer driving module 50, and the galvanometer driving module 50 provides the third galvanometer driving current to the first coil set in the galvanometer 60 for driving the galvanometer to rotate about the first axis as the rotation axis. Referring to fig. 10 (one), the galvanometer 60 is driven by the third galvanometer driving current to deflect by a second angle θ 2 in a second direction F2 (counterclockwise direction) about the first axis X as a rotation axis. This is achieved in that the center point pixel in the third frame sub-image C is shifted in the negative direction of the X1 axis by the distance d2 to the positive direction of the X1 axis, and the shift distance d2 of the center point pixel in the positive direction of the Y1 axis in the third frame sub-image C is kept constant.

Referring to fig. 10 (two), eventually, the coordinates of the center point pixel of the third sub-frame image C in the third coordinate system are (d1, d1), i.e., the center point pixel of the third sub-frame image C is located at the C position of the third coordinate system. Referring to fig. 6, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the blue primary color light of the three primary colors, the galvanometer 60 is deflected from the negative direction of the second axis Y to the positive direction of the second axis Y with the first axis X as a rotation axis, and does not rotate with the second axis Y as a rotation axis, that is, the galvanometer 60 is kept unchanged in the positive direction of the first axis X. Then, when the light valve 40 receives the primary color light of green and the primary color light of red in the primary color light in sequence, the galvanometer 60 remains unchanged, i.e., the galvanometer 60 is not deflected until the display of the third frame sub-image C is completed.

Referring to fig. 6, 8 and 11, during the projection display of the fourth frame sub-image D, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the blue primary color in the three primary colors, the display control module 10 may transmit a fourth galvanometer current control signal to the galvanometer driving module 50, the galvanometer driving module 50 provides a fourth galvanometer driving current to the second coil group for driving the galvanometer 60 to rotate around the second axis as the rotation axis, the fourth galvanometer driving current is t3 segment and t4 segment in the current waveform diagram shown in fig. 8, the current in the t3 segment is used for driving the galvanometer 60 to deflect from the positive direction of the first axis X to the negative direction of the first axis X around the second axis Y as the rotation axis, and the t4 segment is used for controlling the galvanometer 60 to remain unchanged.

When the fourth mirror driving current is at t 3. Referring to fig. 11 (one), the galvanometer 60 is driven by the fourth galvanometer driving current to deflect by a second angle θ 2 along a third direction F3 (i.e., clockwise) with the second axis Y as a rotation axis. Thereby, it is achieved that the center point pixel of the fourth frame sub-image D is shifted in the positive direction of the Y1 axis by the distance D2 to the negative direction of the Y1 axis, and the shift distance D2 of the center point pixel of the fourth frame sub-image D in the positive direction of the X1 axis is kept constant. Referring to fig. 11 (two), finally, the coordinates of the center point pixel of the fourth frame sub-image D in the third coordinate system are (D1, -D1), i.e., the center point pixel of the fourth frame sub-image D is located at the D position of the third coordinate system.

When the driving current waveform illustrated in fig. 8 is applied to the projection apparatus to swing the galvanometer, the positive and negative swing amplitudes of the mirror surface are relatively small with respect to the mirror surface of the galvanometer as a vibration starting reference surface, the deformation of the metal elastic sheet of the galvanometer is small, the positive and negative swing is easy for the elastic recovery of the metal elastic sheet, the design requirement on the metal structure is relatively low, and the implementation is easier.

And because the driving current waveform is positive and negative symmetrical, the amplitude of the driving current can be relatively small. For example, 2.7 μm displacement is achieved in one direction, while the current shown in fig. 8 is in both positive and negative directions, so that the positive or negative direction only needs to reach 2.7/2 μm, and thus the required driving current is also small.

As another embodiment of the present application, FIG. 9 provides a waveform diagram of another galvanometer drive current for driving the galvanometer in deflection along a second axis. The abscissa of the waveform chart represents time t, and the ordinate represents the magnitude of the drive current I.

The waveform of the second galvanometer driving current can refer to segments t1 and t2 in the current waveform diagram shown in fig. 9, the current in the segment t1 is used for driving the galvanometer to deflect from the initial position of the first axis X to the positive direction of the first axis X with the second axis Y as the rotation axis, and the segment t2 is used for controlling the galvanometer 60 to be kept unchanged.

When the second galvanometer driving current is at segment t1, referring to (one) and (two) of fig. 7, the galvanometer 60 is driven by the second galvanometer driving current to deflect by the target angle θ along the second direction F2 (i.e., counterclockwise) with the second axis Y as the rotation axis. This is achieved by shifting the center point pixel of the second sub-frame image B from the initial position of the Y1 axis by the distance d to the positive direction of the Y1 axis, and finally the coordinates of the center point pixel of the second sub-frame image B in the third coordinate system are (0, d), that is, the center point pixel of the second sub-frame image B is located at the B position of the third coordinate system.

Referring to fig. 6, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the blue primary color in the three primary colors, the galvanometer 60 is deflected from the initial position of the first axis X to the positive direction of the first axis X with the second axis Y as the rotation axis, and does not rotate with the first axis X as the rotation axis, that is, the galvanometer 60 is kept unchanged at the initial position of the second axis Y. Thereafter, when the light valve 40 receives the primary color light of green and the primary color light of red in the primary color light sequentially, referring to fig. 9, the second galvanometer driving current is t2 segment, and at this time, the galvanometer 60 remains unchanged, i.e., the galvanometer 60 is not deflected until the display of the second frame sub-image B is completed.

Referring to fig. 6, 7 and 10, in the process of displaying the third frame sub-image C by projection, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the blue primary color in the three primary colors, the display control assembly 10 may transmit the third galvanometer current control signal to the galvanometer driving assembly 50, and the galvanometer driving assembly 50 provides the third galvanometer driving current to the first coil set in the galvanometer 60 for driving the galvanometer to rotate with the first axis X as the rotation axis. Referring to fig. 10 (one), the galvanometer 60 is driven by the third galvanometer driving current to deflect a target angle θ in a third direction F3 (i.e., counterclockwise) about the first axis X as a rotation axis.

Referring to (two) in fig. 10, it is thereby achieved that the center point pixel of the third frame sub-image C is shifted by the distance d from the initial position of the X1 axis to the positive direction of the X1 axis, and the shift distance d of the center point pixel of the third frame sub-image C in the positive direction of the Y1 axis is kept unchanged. Finally, the coordinates of the central pixel of the third sub-frame image C in the third coordinate system are (d, d), that is, the central pixel of the third sub-frame image C is located at the position C of the third coordinate system. Referring to fig. 6, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the blue primary color in the three primary colors, the galvanometer 60 is deflected from the initial position of the second axis Y to the positive direction of the second axis Y with the first axis X as the rotation axis, and does not rotate with the second axis Y as the rotation axis, that is, the galvanometer 60 is kept unchanged in the positive direction of the first axis X. Then, when the light valve 40 receives the primary color light of green and the primary color light of red in the primary color light in sequence, the galvanometer 60 remains unchanged, i.e., the galvanometer 60 is not deflected until the display of the third frame sub-image C is completed.

Referring to fig. 6, 7 and 10, during the projection display of the fourth frame sub-image D, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the blue primary color in the three primary colors, the display control module 10 may transmit a fourth galvanometer current control signal to the galvanometer driving module 50, the galvanometer driving module 50 provides a fourth galvanometer driving current to the second coil group in the galvanometer 60 for driving the galvanometer to rotate around the second axis Y as a rotation axis, the fourth galvanometer driving current is t3 segment and t4 segment in the current waveform diagram shown in fig. 9, the current of the t3 segment is used for driving the galvanometer to be deflected to the initial position of the first axis X by the positive direction of the first axis X shown in (one) in fig. 7, and the t4 segment is used for driving the galvanometer to be kept unchanged.

In contrast, in the mirror driving current shown in fig. 9, the current direction is unidirectional, i.e., always positive, and the current direction of the mirror driving current can be kept constant, so that the deflection direction of the mirror 60 is a fixed direction. In order to achieve the same degree of swing, the unidirectional swing amplitude of the mirror surface is large, and the requirements on the structure design of the galvanometer and the elasticity of the metal elastic sheet are high, but in the driving mode shown in fig. 9, the driving circuit is simple and the cost is relatively low.

Referring to fig. 6, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the blue primary color light of the three primary colors, the galvanometer 60 is deflected from the positive direction of the first axis X to the negative direction of the first axis X with the second axis Y as the rotation axis, and does not rotate with the first axis X as the rotation axis, that is, the galvanometer 60 is kept unchanged in the positive direction of the second axis Y. Then, when the light valve 40 receives the primary color light of green and the primary color light of red in the primary color light sequentially, and the fourth galvanometer driving current is at segment t4, the galvanometer 60 remains unchanged, i.e., the galvanometer 60 is not deflected until the fourth frame sub-image D is displayed completely. Therefore, the first sub-frame image A, the second sub-frame image B, the third sub-frame image C and the fourth sub-frame image D are displayed on the projection screen in a superposition mode, and therefore a high-resolution target image is displayed on a low-resolution projection device.

Referring to fig. 6 and 12, in the process of displaying the first frame sub-image a of the next frame target image by projection, the light valve 40 receives the illumination of the three primary colors in a time sequence, and when the light valve 40 receives the illumination of the blue primary color in the three primary colors, the display control assembly 10 may transmit the first galvanometer current control signal to the galvanometer driving assembly 50, and the galvanometer driving assembly 50 provides the first galvanometer driving current to the first coil set of the galvanometer 60 for driving the galvanometer to rotate around the first axis X as the rotation axis. Referring to fig. 12, the galvanometer 60 is driven by the first galvanometer driving current to deflect by a second angle θ 2 along a first direction F1 (i.e., clockwise) about the first axis X as a rotation axis. It is thereby achieved that the center point pixel of the first frame sub-image a of the next frame target image is shifted in the positive direction by the distance d2 to the negative direction of the X1 axis along the X1 axis, and the shift distance d2 of the center point pixel of the first frame sub-image a of the next frame target image in the negative direction of the Y1 axis is kept constant. Finally, the coordinates of the center point pixel of the first frame sub-image a of the next frame target image in the third coordinate system are (-d 1), i.e., the center point pixel of the first frame sub-image a of the next frame target image is located at the position a of the third coordinate system. Then, when the color of the light irradiated to the light valve 40 by the laser changes to green and red in turn, the galvanometer 60 remains unchanged, that is, the galvanometer 60 is not deflected until the first frame sub-image a of the next frame target image is displayed, and so on, the multiple frames of target images are displayed on the projection screen.

In the embodiment of the present disclosure, the waveform of the galvanometer driving current may be a sine wave regardless of a bipolar (positive and negative directions) or unipolar (only one direction, such as a positive direction) driving manner, and compared with a square wave, the sine wave has fewer harmonic components, generates less noise in the process of implementing electromagnetic driving, requires less electromagnetic torque, and can reduce heat generation of the coil.

In the embodiment of the present disclosure, the galvanometer driving component 50 drives the galvanometer 60 to deflect in two directions with the first axis or the second axis as a rotation axis by supplying the galvanometer driving current with a current direction alternating to the galvanometer 60. The amplitude of the galvanometer driving current is small, so that when the galvanometer 60 deflects by taking the first axis or the second axis as a rotating axis, the deflection amplitude in each direction is small, and the deformation amount of the bearing plate in the galvanometer 60 is small. The method for driving the galvanometer has low requirement on the structure of the bearing plate, reduces the damage rate of the bearing plate, prolongs the service life of the bearing plate and further prolongs the service life of the galvanometer.

It should be noted that the order of the steps of the projection display method provided by the embodiment of the present disclosure may be appropriately adjusted, for example, step 304 and step 305 may be executed simultaneously. Any method that can be easily conceived by those skilled in the art within the technical scope of the present disclosure is covered by the protection scope of the present disclosure, and thus, the detailed description thereof is omitted.

In summary, the embodiment of the present disclosure provides a projection apparatus, which may transmit a galvanometer current control signal corresponding to each sub-image to a galvanometer driving component in a process of displaying each sub-image by projection, so that the galvanometer driving component provides a galvanometer driving current to the galvanometer to drive the galvanometer to deflect. The current control signals of the galvanometer corresponding to different frames of sub-images are different, so that the galvanometer can be driven to deflect to different positions, the multiple frames of sub-images are displayed on a projection screen in a superposition mode, and the high-resolution target image is displayed on the projection equipment with low resolution under the condition that pixel information of the target image is not lost.

And, in this example, the galvanometer is composed of a circuit board and an optical mirror surface provided on the circuit board. The circuit board is provided with a hollow area, the optical mirror is correspondingly arranged, and a driving component, namely a coil, for driving the optical mirror to vibrate is directly printed on the circuit board, so that the circuit board is different from a winding type in a traditional product, on one hand, the space of the coil is greatly reduced, the connection structure between the coil and the optical glass is simplified, and meanwhile, copper wires laid on the circuit board around the coil are beneficial to rapid heat dissipation.

The optical mirror surface is bonded to the hollow-out area of the circuit board through the elastic gasket, on one hand, the whole vibrating mirror structure is in a plate shape, the internal installation of the projection equipment is facilitated, meanwhile, the structure is arranged to enable the noise to be low, the plate-shaped structure is easy to realize surface fixing through multiple fixing parts during fixed installation, the transmission of vibration in all directions is reduced, and therefore noise reduction is facilitated. The laser projection device can achieve the purposes of miniaturization and low noise of the projection device.

The above description is intended to be exemplary only and not to limit the present disclosure, and any modification, equivalent replacement, or improvement made without departing from the spirit and scope of the present disclosure is to be considered as the same as the present disclosure.

Claims

1. A projection device, characterized in that the projection device comprises:

a light source for emitting a three-color light beam;

the light valve is used for modulating and outputting the three-color light beams;

the galvanometer is positioned between the light valve and the projection lens and used for changing the position of the light beam output by the light valve under the control of the driving current;

the projection lens is used for imaging the light beams at different positions output by the galvanometer;

the vibrating mirror comprises a circuit board and an optical mirror surface arranged on the circuit board, wherein the circuit board is used for driving the optical mirror surface to turn over under the electromagnetic action.

2. The projection device of claim 1,

the circuit board includes: a substrate and a plurality of coil groups; the substrate has a first hollowed-out area and a first edge area surrounding the first hollowed-out area,

the plurality of coil groups are printed on the first edge area;

and the optical mirror surface is arranged at the first hollow-out area.

3. The projection device of claim 2,

the optical mirror includes: the optical glass is positioned on one side, close to the circuit board, of the bearing plate, and the magnetic assemblies are arranged on the other side, close to the circuit board, of the bearing plate;

the bearing plate is provided with a second hollow-out area and a second edge area surrounding the second hollow-out area, the optical glass covers the second hollow-out area, the magnetic assemblies are located in the second edge area, and the orthographic projection of the optical glass on the substrate and the orthographic projection of the second hollow-out area on the substrate are both overlapped with the first hollow-out area.

4. The projection apparatus according to claim 3, wherein each of the coil groups includes a first coil and a second coil, one end of the first coil is connected to a positive electrode, the other end of the first coil is connected to one end of the second coil, and the other end of the second coil is connected to a negative electrode; each magnetic assembly comprises a first magnetic assembly and a second magnetic assembly;

the first coil is arranged around a first central area, and the first central area is overlapped with the orthographic projection of the first magnetic assembly on the substrate;

the second coil is disposed around a second central region that overlaps an orthographic projection of the second magnetic assembly on the substrate.

5. The projection device of claim 3, wherein the first and second hollowed-out regions are both centrosymmetric regions; the plurality of coil groups comprise a first coil group and a second coil group, and the optical mirror comprises two magnetic components;

the first coil and the second coil in each coil group are oppositely arranged on two sides of the first hollowed-out area, and the coils in the different coil groups are located on different sides of the first hollowed-out area.

6. A projection device according to any of claims 2-5, wherein the turns of each coil assembly are printed on the substrate in a gapped winding.

7. The projection device of any of claims 2-5, wherein the substrate has at least two layers, and at least one of the coil assemblies is switchable from a bottom layer of the substrate to a top layer of the substrate.

8. The projection device of claim 7, wherein the substrate comprises a first sub-substrate and a second sub-substrate; each layer of the sub-substrate is provided with a first coil group and a second coil group;

one end of the first coil in the first sub-substrate is connected with the positive electrode, and the other end of the first coil in the first sub-substrate is connected with one end of the first coil on the second sub-substrate through a first via hole;

the other end of the first coil on the second sub-substrate is connected with one end of the second coil on the second sub-substrate, the other end of the second coil on the second sub-substrate is connected with one end of the second coil on the first sub-substrate through a second through hole, and the other end of the second coil on the first sub-substrate is connected with the negative electrode.

9. The projection device of claim 3, wherein the substrate comprises four resilient pads, the second edge region comprises four corner regions, each resilient pad is fixedly connected to one corner region of the second edge region, and the resilient pads are configured to support the optical mirrors.

10. The projection apparatus according to claim 3, wherein the second edge region is further provided with a plurality of third hollow-out regions, the plurality of third hollow-out regions surround the second hollow-out region, and a connection shaft exists between any two adjacent third hollow-out regions, and the connection shaft is a rotation shaft of the optical mirror.

11. The projection apparatus as claimed in claim 3 or 10, wherein the carrier plate is made of a metal material, and one end of each of the magnetic members close to the carrier plate has a polarity opposite to that of the other end far from the carrier plate.

12. The projection device according to claim 3 or 10, wherein the optical glass is used for transmitting light beams, the thickness of the optical glass ranges from 1.95mm to 2.05mm, and the optical glass is circular or rectangular.

13. The projection device of claim 3 or 10, wherein the optical glass has a size larger than that of the second hollow area, and the optical glass is adhered to the second edge area of the carrier plate;

the magnetic assemblies are adhered to different sides of the second hollowed-out area.

14. The projection apparatus as claimed in claim 3 or 10, wherein the plate surface of the carrier plate is a smooth mirror surface, the optical glass is carried on the smooth mirror surface side of the carrier plate, and the smooth mirror surface side is close to the light valve.

15. The projection device of claim 2, wherein the first edge region further comprises a plurality of through holes for securing the circuit board.

16. The projection device of claim 3,

the projection device further comprises a galvanometer driving component for providing galvanometer driving current to each coil group so as to drive the optical mirror surface to deflect;

each coil set is used for interacting with the magnetic assembly under the driving of the driving current so as to drive the optical glass to rotate along one rotating shaft, and the rotating shafts corresponding to different coil sets intersect.

17. The method of claim 16, wherein the galvanometer drive current is used to drive the galvanometer to deflect about at least one of a first axis and a second axis, the first axis and the second axis being orthogonal to each other.

18. The method of claim 16, wherein the galvanometer driving current is driven by alternating positive and negative current directions; or, the current direction of the galvanometer driving current is unchanged, and the galvanometer is driven.

19. The projection device of claim 18, wherein the mirror drive current has a sine wave shape.