Air ionization display apparatus and control method therefor

Abstract

To provide an air ionization display apparatus and a control method therefor, which relate to the field of imaging technologies.SOLUTION: A control method of an air ionization display apparatus includes the steps of: splitting, by a pulse laser light source, an output pulse laser beam into a first sub-beam and a second sub-beam; regulating, by a pulse laser regulation assembly, the second sub-beam to obtain a third sub-beam, and regulating a time difference from the first sub-beam to delay an emission of the third sub-beam; combining the first sub-beam and the third sub-beam to obtain a combined beam; converging, by a light field adjustment and control assembly, the combined beam, and ionizing the air at a display region to form a holographic image; and obtaining luminance information of the holographic image and controlling the pulse laser regulation assembly and the light field adjustment and control assembly so that the luminance of the holographic image satisfies a predetermined condition.SELECTED DRAWING: Figure 12

Description

[Technical Field]

[0001] The present disclosure relates to the field of imaging, and more particularly to an air ionization display device and a control method thereof. [Background technology]

[0002] In the imaging process, air ionization imaging systems focus a beam using a lens, ionizing the air at the lens's focal point to form a light spot. Because the pulse's optical power per unit area required to ionize the air is high, the number of focal spots formed by the spatial light modulator that modulates the light field at each ionization point is limited by the pulse power. In other words, the number of pixels in the displayed image is constrained by the magnitude of the pulse power. To increase the number of pixels in the displayed image, the output pulse power of the light source must be further increased, but with conventional technology, it is difficult to significantly increase the output pulse power of the light source.

[0003] In addition, optical components such as zoom lenses in air ionization display systems have limited damage thresholds, and typically cannot withstand the long-term operation of high-peak-power-density pulsed lasers. As a result, there is an upper limit to the output pulse power of the light source. Due to these factors, the image area displayed by air ionization is small, and cannot meet the needs of large-image aerial imaging displays. Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure aims to solve at least one of the technical problems in the related art to some extent. Therefore, a first objective of the present disclosure is to provide an air ionization display device that achieves wide-area air ionization with a relatively low output power of a laser light source.

[0005] A second object of the present disclosure is to provide a method for controlling an air ionization display device.

[0006] To achieve the above object, an embodiment of a first aspect of the present disclosure provides an air ionization display device, the air ionization display device including: a pulsed laser light source that generates a pulsed laser beam; a beam splitter that splits the pulsed laser beam into a first sub-beam and a second sub-beam; a pulsed laser adjustment assembly that adjusts the wavelength of the second sub-beam to obtain a third sub-beam and adjusts a time difference between the third sub-beam and the first sub-beam to delay the emission of the third sub-beam; a beam combiner that combines the first sub-beam and the delayed emitted third sub-beam to obtain a combined beam; and a light field adjustment and control assembly that adjusts and focuses the combined beam to ionize air in a display area and form a holographic image.

[0007] In order to achieve the above object, an embodiment of a second aspect of the present disclosure provides a control method for an air ionization display device, the method being applicable to the above air ionization display device, the method including the steps of: outputting a pulsed laser beam by the pulsed laser light source and splitting the pulsed laser beam into a first sub-beam and a second sub-beam by the beam splitter; adjusting a wavelength of the second sub-beam by the pulsed laser adjusting assembly to obtain a third sub-beam and adjusting a time difference between the third sub-beam and the first sub-beam to delay emission of the third sub-beam; combining the first sub-beam and the delayed emitted third sub-beam by the beam combiner to obtain a combined beam; adjusting and focusing the combined beam by the light field adjusting and control assembly to ionize air in a display area to form a hologram image; and acquiring brightness information of the hologram image, and controlling the pulsed laser adjusting assembly and the light field adjusting and control assembly based on the brightness information of the hologram image so that the brightness of the hologram image satisfies a predetermined condition.

[0008] In an air ionization display device and a control method thereof according to an embodiment of the present disclosure, a pulsed laser light source generates a pulsed laser beam, a beam splitter then splits the pulsed laser beam into a first sub-beam and a second sub-beam, a pulsed laser adjustment assembly adjusts the wavelength of the second sub-beam to obtain a third sub-beam and adjusts the time difference between the third sub-beam and the first sub-beam to delay the emission of the third sub-beam, a beam combiner combines the first sub-beam and the second sub-beam to obtain a combined beam, and a light field adjustment and control assembly adjusts and focuses the combined beam to ionize air in a display area and form a holographic image. This makes it possible to achieve wide-area air ionization with a relatively low output power of the laser light source.

[0009] Additional aspects and advantages of the present disclosure will be set forth at least in part in the description that follows, or will be at least in part obvious from the description, or may be learned through the practice of embodiments of the present disclosure. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a block diagram showing the structure of an air ionization display device according to an embodiment of the present disclosure. [Figure 2] FIG. 10 is a block diagram showing the structure of an air ionization display device according to another embodiment of the present disclosure. [Figure 3] FIG. 10 is a block diagram showing the structure of an air ionization display device according to yet another embodiment of the present disclosure. [Figure 4] FIG. 1 is a schematic diagram illustrating the structure of an optical delay line according to an example of the present disclosure. [Figure 5] FIG. 10 is a schematic diagram illustrating the structure of an optical delay line according to another example of the present disclosure. [Figure 6] FIG. 2 is a schematic diagram showing the structure of a light field adjustment control assembly in the first example of the present disclosure. [Figure 7] FIG. 10 is a schematic diagram showing the structure of a light field adjustment control assembly in the second example of the present disclosure. [Figure 8] FIG. 10 is a schematic diagram showing the structure of a light field adjustment control assembly in the third example of the present disclosure. [Figure 9] FIG. 10 is a schematic diagram showing the structure of a light field adjustment control assembly in the fourth example of the present disclosure. [Figure 10] FIG. 10 is a schematic diagram showing the structure of a light field adjustment control assembly in the fifth example of the present disclosure. [Figure 11] 1 is an operation flowchart of an air ionization display device according to an embodiment of the present disclosure. [Figure 12] 10 is a flowchart of a control method for an air ionization display device according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present disclosure will be described in detail with reference to examples shown in the accompanying drawings, in which identical or similar components or components having identical or similar functions are denoted by identical or similar reference numerals. The embodiments described below with reference to the drawings are merely exemplary and are used to explain the present disclosure, but should not be understood as limiting the present disclosure.

[0012] Hereinafter, an air ionization display device and a control method thereof according to an embodiment of the present disclosure will be described with reference to the drawings.

[0013] FIG. 1 is a block diagram showing the structure of an air ionization display device according to an embodiment of the present disclosure.

[0014] As shown in FIG. 1, the air ionization display device 10 includes a pulsed laser source 11, a beam splitter 12, a pulsed laser adjustment assembly 13, a beam combiner 14, and a light field adjustment control assembly 15.

[0015] Specifically, the pulsed laser light source 11 is used to generate a pulsed laser beam, the beam splitter 12 is used to split the pulsed laser beam into a first sub-beam and a second sub-beam, the pulsed laser adjustment assembly 13 is used to adjust the wavelength of the second sub-beam to obtain a third sub-beam and adjust the time difference between the third sub-beam and the first sub-beam to delay the emission of the third sub-beam, the beam combiner 14 is used to combine the first sub-beam and the delayed third sub-beam to obtain a combined beam, and the light field adjustment control assembly 15 is used to adjust and focus the combined beam and ionize the air in the display area to form a holographic image.

[0016] Here, the pulsed laser beam generated from the pulsed laser source 11 may have a pulse width of 50 fs to 100 ns, pulse energy of 20 μJ to 10 mJ, a repetition rate of 500 Hz to 10 MHz, and a wavelength of 1000 nm to 1200 nm. After the pulsed laser source 11 generates the pulsed laser beam, the pulsed laser beam is split into a first sub-beam and a second sub-beam via a beam splitter 12.

[0017] Furthermore, after splitting the pulsed laser beam into a first sub-beam and a second sub-beam via the beam splitter 12, the first sub-beam passes through the beam splitter 12 to a beam combiner 14, and the second sub-beam passes through the beam splitter 12 to a pulsed laser adjustment assembly 13.

[0018] The first sub-beam passes through beam combiner 14 and reaches light field conditioning and control assembly 15, which conditions and focuses the first sub-beam to excite air molecules or atoms in the display area to a first excited state. Because the ionization potential range of most molecules or atoms is between 5 and 20 eV, the wavelength range for single-photon ionization is 62 to 248 nm, as can be seen from E = hλ / c. This means that a single ultraviolet photon or a photon in the visible light band cannot ionize air atoms or molecules. Therefore, the first sub-beam excites air atoms or molecules in the display area to a low-energy, first excited state.

[0019] The pulsed laser adjustment assembly 13 adjusts the second sub-beam to obtain a third sub-beam. The wavelength of the third sub-beam may be 800 nm to 2000 nm, and the repetition rate of the third sub-beam is the same as that of the second sub-beam. The pulsed laser adjustment assembly 13 then delays and outputs the third sub-beam to the beam combiner 14. The third sub-beam passes through the beam combiner 14 and reaches the light field adjustment control assembly 15, which adjusts and focuses the third sub-beam. Since the first sub-beam has already excited the air in the display area to a first excited state, the third sub-beam re-excites atoms or molecules already excited to the lower first excited state in the air, thereby ionizing the air.

[0020] Specifically, the number of ionized atoms has the following relationship with the optical flow density of the combined beam, the wavelength of the first sub-beam, and the wavelength of the third sub-beam.

number

number

number

[0021] Here, N0(t) is the total number of atoms, N1(t) is the number of atoms in the first excited state, and σ A is the induced absorption cross section from the ground state to the first excited state, and σ i is the ionization cross section from the first excited state to the continuum, τ is the spontaneous emission lifetime of the first excited state, Φ is the optical flow density of the combined beam, and N i (t) is the number of ionized atoms. A is related to the wavelength of the first sub-beam, and the above σ i is related to the wavelength of the third sub-beam.

[0022] By adding the above equations (1) and (2) and differentiating the above equation (3), the following can be obtained:

number

number

number

number

number

number

number

number

[0023] By adjusting the delay time of the third sub-beam, the third sub-beam can again excite atoms or molecules in the air at an appropriate time after the first sub-beam excites molecules or atoms in the air to the first excited state. Furthermore, by adjusting the wavelength of the third sub-beam, the third sub-beam can resonantly excite atoms or molecules in the first excited state, thereby lowering the threshold output power required for the laser to ionize the air, and achieving wide-area air ionization even with a low output power of the laser light source.

[0024] The extinction ratio of the beam splitter 12 is set to Tp:Ts>1000:1, the extinction ratio of the beam combiner 14 is set to Tp:Ts>1000:1, and the light field adjustment control assembly 15 can be controlled so that the scanning range of the combined beam is 100-200 mm in the X direction, 100-200 mm in the Y direction, and 100-200 mm in the Z direction. The display area is preferably a three-dimensional display area and is larger than the scanning range of the combined beam.

[0025] Further, see Figure 2. The air ionization display device 10 further includes a controller 16 and a half-wave plate 17, and the controller 16 is connected to the pulsed laser light source 11, the pulsed laser adjustment assembly 13, and the light field adjustment control assembly 15.

[0026] Specifically, the controller 16 controls the display of the hologram image in the display area by controlling the laser output from the pulsed laser light source 11, the pulsed laser adjustment assembly 13, and the light field adjustment control assembly 15 based on the brightness information of the hologram image.

[0027] The half-wave plate 17 is used to adjust the polarization of the pulsed laser beam output from the pulsed laser source 11. The pulsed laser beam generated from the pulsed laser source 11 becomes horizontally polarized and vertically polarized after passing through the half-wave plate 17, and the polarization can be further filtered using the beam splitter 12 and the beam combiner 14. For example, the reflectance of the beam splitter 12 for horizontally polarized light may be set to 0.5% to 1%, and the reflectance of the beam combiner 14 for vertically polarized light may be set to 99% to 99.5%, so that the combined beam is approximately horizontally polarized. Here, the size of the half-wave plate 17 may be 20 mm to 30 mm.

[0028] Further, see Figure 3. The pulsed laser adjustment assembly 13 comprises a pulsed laser regulator 131 and an optical delay line 132.

[0029] Specifically, the pulsed laser regulator 131 is used to adjust the wavelength of the second sub-beam to obtain the third sub-beam. For example, the second sub-beam serves as an excitation source for the pulsed laser regulator 131 to excite the laser working material in the pulsed laser regulator 131, and the pulsed laser adjusting assembly 13 generates the third sub-beam. Alternatively, the wavelength of the second sub-beam can be changed by passing the second sub-beam through a predetermined medium.

[0030] Furthermore, the optical delay line 132 is used to adjust the time difference between the third sub-beam and the first sub-beam to delay the emission of the third sub-beam.

[0031] 4, the optical delay line 132 includes a corner cube reflector 1321 and a motorized linear stage 1322. The corner cube reflector 1321 includes two total reflection mirrors that are perpendicular to each other, and is used to reflect the third sub-beam emitted from the pulsed laser regulator 131 to the beam combiner 14. The motorized linear stage 1322 is used to drive the corner cube reflector 1321 to move it in the incident direction of the third sub-beam. The precision of the motorized linear stage 1322 may be 1 μm to 10 μm.

[0032] Optionally, see Figure 5. The optical delay line 132 further includes a first corner cube reflector 1323, a second corner cube reflector 1324, a first reflecting mirror 1325, and a second reflecting mirror 1326, and may further include a motorized linear stage 1322. The first corner cube reflector 1323 and the second corner cube reflector 1324 each include two total reflecting mirrors that are perpendicular to each other and are installed such that one total reflecting mirror of the first corner cube reflector 1323 faces one total reflecting mirror of the second corner cube reflector 1324. The first reflecting mirror 1325 is used to reflect the third sub-beam emitted from the pulsed laser regulator 131 to the other total reflecting mirror of the first corner cube reflector 1323, and the second reflecting mirror 1326 is used to reflect the third sub-beam emitted from the other total reflecting mirror of the second corner cube reflector 1324 to the beam combiner 14. The motorized linear motion stage 1322 is used to drive at least one corner cube reflector to move it in the incident direction of the third sub-beam. There may be more than one motorized linear motion stage 1322, and each motorized linear motion stage 1322 corresponds one-to-one to the corner cube reflector. The precision of the motorized linear motion stage 1322 may be 1 μm to 10 μm.

[0033] The time difference between the third sub-beam and the first sub-beam may be 100 fs to 10 ns, and is preferably 1 ps.

[0034] Further, please refer to Fig. 6. The light field adjustment control assembly 15 includes an adjustment unit 151, a focus unit 152 and a zoom unit 153.

[0035] Specifically, the adjustment unit 151 is used to adjust the direction of the composite beam, the focus unit 152 is used to focus the composite beam after the direction has been adjusted in the display area and ionize the air at the focal position to form an image, and the zoom unit 153 is installed between the galvanometer scanner unit and the focus unit 152 and is used to adjust the divergence angle of the beam emitted from the galvanometer scanner unit and adjust the depth position of the focal point to display a hologram image.

[0036] Here, the adjustment unit 151 includes a galvanometer scanner assembly, which includes two pairs of reflecting mirrors installed perpendicular to each other; the focus unit 152 includes a flat-field focus lens assembly; and the zoom unit 153 includes a zoom lens assembly. The two pairs of reflecting mirrors in the galvanometer scanner unit deflect horizontally and vertically, respectively, thereby controlling the position of the focal point on a plane. For example, the galvanometer scanner assembly can be used to adjust the position of the focal point in the X and Z directions, and the zoom unit 153 can be used to adjust the position of the focal point in the Y direction. Furthermore, the focus unit 152 ionizes the air at the focal point to form an image. This allows a hologram image to be displayed by scanning the display area.

[0037] Optionally, the adjustment unit 151, focus unit 152, and zoom unit 153 may all be replaceable units, and the user can replace each component in the light field adjustment control assembly 15 by himself, so that the light field adjustment control assembly 15 can better meet the user's own needs.

[0038] For an example, see FIG. 7. The adjustment unit 151 may include an ultra-high-speed polygonal rotating mirror assembly. The ultra-high-speed polygonal rotating mirror assembly includes a polygonal reflector that can rotate at high speed. The zoom unit 153 includes an ultra-high-speed deformable mirror assembly, which includes a piezoelectric material driver and a reflective mirror. The ultra-high-speed polygonal rotating mirror assembly is a polygonal reflector that can rotate at high speed, with a light-transmitting hole diameter of 15 to 20 mm. Since the polygonal reflector rotates in only one direction, it can rotate at high speed, with a rotation speed of 500 to 600 m / s. The reflective mirror may be composed of multiple small mirrors or may be a single thin reflective surface. This can improve the imaging speed of the light field adjustment control assembly 15.

[0039] 8. The adjustment unit 151 may include a MEMS (Micro-Electro-Mechanical System) micromirror, which includes a reflective mirror 20, a fixed electrode 21, and a movable electrode 22. The MEMS micromirror can be deflected in a specific manner and time sequence to enter the combined beam in the light field adjustment control assembly 15. The reflective mirror 20 has the characteristics of small size, electrostatic drive, and universality free. The MEMS micromirror has the advantages of high scanning frequency, small size, and low cost, which can improve the imaging speed of the light field adjustment control assembly 15. The scanning frequency of the MEMS micromirror can usually reach 500 to 1000 Hz.

[0040] Alternatively, see FIG. 9 . The adjustment unit 151 may include a liquid crystal optical phased array, which includes a liquid crystal molecular layer 26. The liquid crystal optical phased array can deflect the direction of the combined beam entering the light field adjustment control assembly 15 by adjusting the orientation of the liquid crystal molecular layer 26. The liquid crystal optical phased array has the characteristics of low driving voltage, fast deflection speed, and easy integration with a microelectronic control circuit. In FIG. 9 , 24 denotes the combined beam, and 25 denotes the adjusted combined beam.

[0041] See FIG. 10. The adjustment unit 151 may include a digital microgalvanometer scanner array, which includes a microgalvanometer scanner array mirror 30, such as a DMD (Digital Micromirror Device) chip. The digital microgalvanometer scanner array controls whether the combined beam is focused on the display area by controlling the switches of the microgalvanometer scanner array mirror 30. The resolution of the digital microgalvanometer scanner array can typically reach 1280 x 800, the cell size is 10-20 microns, the available wavelength range is 850-2000 nm, the optical window transmittance is greater than 93%, and the frame rate can reach 5000 fps. The digital microgalvanometer scanner array can improve the frame rate of the 3D display and the imaging speed of the light field adjustment control assembly 15. In FIG. 10, 28 indicates the combined beam, and 29 indicates the adjusted combined beam.

[0042] In one embodiment of the present disclosure, as shown in FIG. 11, the air ionization display device 10 can form a hologram image in the display area by the following steps.

[0043] In S111, the host device outputs a pulse laser beam with a certain repetition frequency and energy as a test pulse based on the optical characteristics of the pulse laser light source.

[0044] In S112, the pulsed laser beam first displays a preliminary test pattern through the light field adjustment control assembly.

[0045] As an example, the test pattern may be, for example, a single square.

[0046] In S113, the subordinate machine controls the electric linear stage to perform delay time tuning, and at the same time, the subordinate machine controls the pulse laser regulator to perform wavelength scanning.

[0047] Specifically, the subordinate machine can control the electric linear stage 1322 to drive the corner cube reflector and move it in the direction of incidence of the third sub-beam to modify the time difference between the third sub-beam and the first sub-beam, and can control the pulse laser regulator 131 to scan the wavelength to modify the wavelength of the third sub-beam.

[0048] In S114, the luminance of the test pattern is collected by the light field adjustment control assembly, converted into an electrical signal, and transmitted to the subordinate device.

[0049] Specifically, the light field adjustment control assembly 15 displays a test pattern in the display area using test pulses and also collects the luminance of the test pattern.

[0050] In S115, the subordinate machine adjusts the electric linear stage and the pulse laser regulator to the optimum positions based on the brightness of the test pattern, where the brightness of the test pattern is the highest.

[0051] Here, the optimum position is the time difference between the third sub-beam and the first sub-beam and the wavelength of the third sub-beam that maximizes the brightness of the test pattern.

[0052] In S116, the host device controls the pulsed laser light source to output a pulsed laser beam having the maximum repetition rate and the minimum energy that satisfies the ionization threshold.

[0053] This allows the light field adjustment and control assembly 15 to scan the display area with the pulsed laser beam.

[0054] In S117, the subordinate machine controls the light field adjustment control assembly to scan and obtain a three-dimensional display pattern. Here, the host device may be, for example, a remote control module, and the subordinate device may be, for example, a field control module. The controller 16 includes the host device and the subordinate device.

[0055] This allows the brightness information of the hologram image to be obtained, and the pulse laser adjustment assembly 13 and the light field adjustment control assembly 15 to be controlled based on the brightness information of the hologram image so that the brightness of the hologram image meets predetermined conditions.

[0056] As described above, an air ionization display device according to an embodiment of the present disclosure splits a pulsed laser beam into a first sub-beam and a second sub-beam using a beam splitter and excites air in a display area to a first excited state using the first sub-beam. The pulsed laser adjustment assembly adjusts the wavelength of the second sub-beam to obtain a third sub-beam and delays the output of the third sub-beam. The third sub-beam is then used to ionize the air in the first excited state, thereby ionizing the air in the display area and forming a holographic image. This allows for wide-area air ionization to be achieved with a relatively low output power of the laser light source, thereby ensuring the safety of the air ionization display device and reducing the cost of the device. Furthermore, forming a holographic image in the display area allows users to directly view a three-dimensional image, improving the user experience.

[0057] FIG. 12 is a flowchart of a control method for an air ionization display device according to an embodiment of the present disclosure.

[0058] In this embodiment, the method for controlling the air ionization display device is used in the air ionization display device of the above embodiment.

[0059] As shown in FIG. 12, the control method for the air ionization display device includes the following steps. In S121, a pulsed laser beam is outputted from a pulsed laser source, and the pulsed laser beam is split into a first sub-beam and a second sub-beam by a beam splitter. In S122, the pulsed laser adjusting assembly adjusts the wavelength of the second sub-beam to obtain a third sub-beam, and delays the emission of the third sub-beam by adjusting the time difference between the third sub-beam and the first sub-beam. In S123, the first sub-beam and the delayed third sub-beam are combined by a beam combiner to obtain a combined beam. At S124, the light field conditioning control assembly conditions and focuses the combined beam to ionize the air in the viewing area to form the holographic image. In S125, brightness information of the hologram image is obtained, and according to the brightness information of the hologram image, the pulse laser adjustment assembly and the light field adjustment control assembly are controlled so that the brightness of the hologram image meets a predetermined condition.

[0060] Optionally, the pulsed laser adjustment assembly and the light field adjustment control assembly may be controlled based on the brightness information of the hologram image, and then the pulsed laser light source may be further controlled to output a laser pulse beam having the maximum allowable repetition rate and the lowest energy that satisfies the air ionization threshold.

[0061] For other specific embodiments of the control method for the air ionization display device according to the embodiments of the present disclosure, please refer to the air ionization display device described above.

[0062] As described above, the method for controlling an air ionization display device according to an embodiment of the present disclosure splits a pulsed laser beam into a first sub-beam and a second sub-beam, adjusts the wavelength of the second sub-beam to obtain a third sub-beam, and simultaneously adjusts the time difference between the third sub-beam and the first sub-beam to delay the emission of the third sub-beam. Finally, the method combines the first sub-beam with the delayed third sub-beam to obtain a combined beam. The combined beam is then used to ionize air in the display area to form a holographic image. Furthermore, brightness information of the holographic image can be obtained, and the brightness of the holographic image is controlled based on the brightness information to satisfy a predetermined condition. This achieves wide-area air ionization with a relatively low output power of the laser light source, thereby ensuring the safety of the air ionization display device and reducing the cost of the device. Furthermore, forming a holographic image in the display area allows users to directly view a 3D image, improving the user experience.

[0063] It should be noted that the logic and / or steps depicted in flowcharts or otherwise described herein can be viewed, for example, as a fixed, sequential listing of executable instructions for implementing logical functions, and can be tangibly embodied in any computer-readable medium and used in an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or a system capable of reading instructions from an instruction execution system, device, or device and executing the instructions), or in combination with such an instruction execution system, device, or device. For purposes of this specification, a "computer-readable medium" may be any device that contains, stores, communicates, propagates, or transmits a program, and is used in an instruction execution system, device, or device, or is used in combination with such an instruction execution system, device, or device. More specific examples (a non-exhaustive list) of computer-readable media include an electrical connection having one or more wires (electronic devices), a portable computer disk case (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CD-ROM). The computer-readable medium may also be paper or other suitable medium on which the program may be printed, for example by optically scanning the paper or other medium and then compiling, interpreting or processing in any other suitable manner as necessary to obtain the program electronically, which is then stored in computer memory.

[0064] It should be understood that each part of the present disclosure can be realized by hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be realized by software or firmware stored in a memory and executed by an appropriate instruction execution system. For example, when realized by hardware, as in other embodiments, the hardware can be realized by any one or combination of techniques known in the art, such as a discrete logic circuit having logic gate circuits for implementing logic functions on data signals, a dedicated integrated circuit having appropriate combinational logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0065] In the description herein, references to "one embodiment," "some embodiments," "one example," "specific example," or "some examples" or the like mean that the specific features, structures, materials, or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the present invention. In the description herein, exemplary references to the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0066] In describing the present disclosure, it should be understood that the orientations or positional relationships indicated by terms such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," etc., are orientations or positional relationships shown in the drawings, are intended solely to facilitate and simplify the description of the present disclosure, and do not indicate or imply that the devices or elements referred to have a particular orientation or are required to be constructed and operated in a particular orientation, and therefore should not be understood as limiting the present disclosure.

[0067] It should be noted that the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or the number of technical features indicated. A feature defined as "first" or "second" may therefore explicitly or implicitly include at least one of the feature. In the description of this disclosure, "plurality" means at least two, e.g., two, three, etc., unless otherwise specified.

[0068] In this disclosure, unless otherwise clearly specified and limited, the terms "attached," "coupled," "connected," "fixed," etc. should be understood in a broad sense, and may refer to, for example, a fixed connection, a detachable connection, or an integral connection, a mechanical connection, an electrical connection, or mutual communication, a direct connection, an indirect connection via an intermediate medium, or an internal communication between two elements or an interactive relationship between two elements. Those skilled in the art can understand the specific meanings of the above terms in this disclosure depending on the specific case.

[0069] In this disclosure, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact via an intermediate medium. Furthermore, a first feature being "above," "above," or "on top of" a second feature may mean that the first feature is directly above or diagonally above the second feature, or simply that the level of the first feature is higher than that of the second feature. A first feature being "below," "below," or "on the bottom of" a second feature may mean that the first feature is directly below or diagonally below the second feature, or simply that the level of the first feature is lower than that of the second feature.

[0070] Although the embodiments of the present disclosure have been shown and described above, the above embodiments are merely examples and the limitations of the present disclosure cannot be understood. Those skilled in the art can change, modify, substitute, and alter the above embodiments within the scope of the present disclosure.

[0071] This disclosure claims priority to a Chinese patent application filed with the China Patent Office on June 22, 2021, bearing application number 202110693799.7 and entitled "Air ionization display device and control method thereof," the entire contents of which are incorporated herein by reference.

Claims

1. A method for controlling an air ionization display device, comprising: outputting a pulsed laser beam from a pulsed laser source and splitting the pulsed laser beam into a first sub-beam and a second sub-beam by a beam splitter; adjusting a wavelength of the second sub-beam by a pulsed laser adjusting assembly to obtain a third sub-beam, and adjusting a time difference between the third sub-beam and the first sub-beam to delay the emission of the third sub-beam; combining the first sub-beam and the delayed third sub-beam by a beam combiner to obtain a combined beam; adjusting and focusing the combined beam with a light field adjustment control assembly to ionize air in a viewing area to form a holographic image; acquiring brightness information of the hologram image, and controlling the pulsed laser adjustment assembly and the light field adjustment control assembly based on the brightness information of the hologram image so that the brightness of the hologram image satisfies a predetermined condition; A method for controlling an air ionization display device, comprising:

2. After the step of controlling the pulsed laser adjustment assembly and the light field adjustment control assembly based on the brightness information of the hologram image, controlling the pulsed laser source to output a laser pulse beam having a maximum allowable repetition rate and a minimum energy that satisfies the air ionization threshold; The method for controlling an air ionization display device according to claim 1 , further comprising:

Images