Meta AR/VR Patent Shares Method for Manufacturing Polarization Selective Elements

CheckCitation/SourcePlease click:XR Navigation Network

(XR Navigation Network 2024年01月05日）诸如偏振选择透镜、光栅和偏转器等偏振选择光学元件在XR应用中获得了越来越多的兴趣。偏振选择光学元件可以基于各向同性或各向异性材料制造，并且可以包括合适的亚波长结构、液晶、光折变全息材料或其组合。

The PVH element and the PBP element are two types of polarization-selective optical elements that provide polarization-selective optical response.The optical axis of the PVH element or the PBP element can have a spatially varying orientation in at least one in-plane direction.The optical axis of the PVH element or the PBP element can also have a spatially varying orientation in an out-of-plane direction.The PBP element and the PVH element are highly planar and compact, high efficiency, large aperture ratio, no axial aberration, switchable, flexible design, simple fabrication and low cost. Therefore, PBP elements and PVH elements can be realized in various applications, such as wearable optical devices or systems.

在名为“System and method for fabricating polarization selective element”的专利申请中，MetaA method of fabricating polarization-selective elements is then described.

FIGS. 4A-4D illustrate the process of polarization selective optical elements (PSOEs) by fabricating them, while the fabrication process is shown in FIG. 5. FIGS. 4A-4D may include holographic recording of an alignment pattern in a photoalignment film, and alignment of an anisotropic material (e.g., LC material) through the photoalignment film. This alignment process may be referred to as surface-mediated photoalignment.

In one embodiment, the PSOE may be fabricated based on the fabrication process shown in FIG. 5. 4A-4D may be polarization-selective gratings, such as PVH gratings, PBP gratings, and the like.

As shown in FIG. 4A, a recording medium layer 410 may be formed above the surface of the substrate 405 by coating or depositing a polarization-sensitive material on the surface of the substrate 405.Thus, said recording medium layer 410 may be referred to as a polarization-sensitive recording medium layer.

The polarization-sensitive material included in the recording medium layer 410 may be an optically recordable and polarization-sensitive material configured to have photo-optical anisotropy when exposed to polarized light irradiation. The molecules and/or photoproducts of the optically recordable and polarization-sensitive material may be configured to be orientationally ordered upon exposure to polarized light irradiation.

In one embodiment, the polarization sensitive material may be dissolved in a solvent to form a solution. Said solution may be coated using any suitable solution coating process. The solvent, in turn, may be removed from the coating solution using a suitable process, such as drying or heating, leaving the polarization sensitive material on top of the substrate 405 to form the recording medium layer 410.

The substrate 405 may provide support and protection for various layers, films, and/or structures formed thereon. In one embodiment, the substrate 405 may be at least partially transparent in at least the visible wavelength band, such as from about 380 nm to about 700 nm. in one embodiment, the substrate 405 may be partially transparent in at least a portion of the infrared wavelength band, such as from about 700 nm to about 4 mm.

The substrate 405 may include a suitable material that is at least partially transparent to light in the wavelength range described above, such as glass, plastic, sapphire, or combinations thereof, and the like. The substrate 405 may be rigid, semi-rigid, flexible or semi-flexible. Said substrate 405 may comprise flat or curved surfaces on which different layers or films may be formed.

The substrate 405 may be used to fabricate, store, or transport the fabricated PSOE. in one embodiment, the substrate 405 may be removable or detachable from the fabricated PSOE after the PSOE is fabricated or after the PSOE is transported to another location or device. In other words, the substrate 405 may be used for fabrication, transportation, and/or storage to support the PSOE provided by the substrate 405, and may be detachable or removable from the PSOE when the fabrication of the PSOE is complete, or when the PSOE is to be implemented in an optical device. In other embodiments, the substrate 405 may not be separated from the PSOE.

After the recording medium layer 410 is formed on the substrate 405, the recording medium layer 410 may be exposed to a polarized interference pattern based on the polarization generated by the two recording beams 440 and 442, as shown in FIG. 4B. Said two recording beams 440 and 442 may be two coherent circularly polarized beams having opposite rotations.

In one embodiment, said recording medium layer 410 may be optically patterned when exposed to a polarized interferogram generated based on said two recording beams 440 and 442 during said polarized interferometric exposure process. The optical axis direction pattern of the recording medium layer 410 in the exposure region may be defined by the polarization interference pattern under which said recording medium layer 410 is exposed during the polarization interference exposure process.

In one embodiment, different regions of the recording medium layer 410 may be exposed to the same or different polarization interference patterns. The same or different orientation patterns of the optical axis of the recording medium 410 may be defined in the respective exposed regions during the respective polarization interference exposure process.

In one embodiment, the recording medium layer 410 may include elongated anisotropic photosensitive units. After sufficient exposure to the polarization interferograms generated based on the two recording light sources 440 and 442, a local alignment direction of the anisotropic photosensitive units can be induced in the recording medium layer 410 by the polarization interferograms, thereby resulting in an alignment pattern of the optical axis of the recording medium layer 410 due to the optical alignment of the anisotropic photosensitive units.

In one embodiment, a plurality of alignment patterns may be recorded in different portions or regions of the recording medium layer 410 by a multipolarization interference exposure process. The plurality of alignment patterns may correspond to a plurality of grating patterns having the same or different sizes, shapes, grating periods, grating orientations, and/or chirality of in-plane modulations.

In one embodiment, the rotationality of the in-plane modulation of the optical axis of the recording medium layer 410 in the exposed region may be controlled by controlling the rotationality of the recording beams 440 and 442.

For example, when the recording beam 440 is an RHCP beam and the recording beam 442 is an LHCP beam, the rotationality of the in-plane modulation of the optical axis of the recording medium layer 410 in said exposed region may be right-handed. When the recording beam 440 is an LHCP beam and the recording beam 442 is an RHCP beam, the rotationality of the in-plane modulation of the optical axis of the recording medium layer 410 in the exposed region may be left-handed. After the recording medium layer 410 is optically patterned, the recording medium layer 410 may be referred to as a patterned recording medium layer having an aligned pattern.

As shown in FIG. 4C, a birefringent medium layer 415 may be formed on top of the patterned recording medium layer 410 by dispensing, for example, coating or depositing a birefringent medium on top of the patterned recording medium layer 410. the birefringent medium may comprise one or more birefringent materials having inherent birefringence.

In one embodiment, the birefringent medium may simultaneously include or be mixed with other ingredients, such as solvents, initiators, chiral dopants, or surfactants.

In one embodiment, the birefringent medium may not have inherent chirality or induced chirality. The birefringent medium may have inherent or induced chirality. For example, the birefringent medium may include a host birefringent material and a chiral dopant doped into the host birefringent material at a predetermined concentration. The chirality may be introduced by doping a chiral dopant into the host birefringent material, e.g., a chiral dopant doped into a nematic lc, or a chiral reactive medium doped into non-chiral RMs.

In one embodiment, the birefringent medium may comprise a birefringent material having inherent molecular chirality, and the chiral dopant may be undoped into the birefringent material. The chirality of the birefringent medium may be determined by the inherent molecular chirality of the birefringent material. For example, the birefringent material may include a chiral liquid crystal molecule, or a molecule having one or more chiral functional groups.

In one embodiment, the birefringent medium may be dissolved in a solvent to form a solution. An appropriate amount of the solution may be dispensed over the patterned recording medium layer 410 to form the birefringent medium layer 415. in one embodiment, the solution containing the birefringent medium may be used with a suitable process.

In one embodiment, the birefringent medium may be heated to remove the remaining solvent. This process may be referred to as pre-exposure heating. The patterned recording medium layer 410 may be configured to provide surface alignment to optically anisotropic molecules in the birefringent medium. For example, the patterned recording medium layer 410 may at least partially align LC molecules or RM molecules in the birefringent medium in contact with the grating patterned recording medium layer 410.

In other words, the LC molecules or RM molecules in the birefringent medium may be at least partially aligned along the direction of the local alignment of the anisotropic photosensitive units in the patterned recording medium layer 410 to form a grating pattern. In this way, the grating pattern recorded in the patterned recording medium layer 410 (may be transferred to the birefringent medium and thus to the birefringent medium layer 415. That is, the patterned recording medium layer 410 may act as a light-aligning material (PAM) layer for LC or RM in the birefringent medium. Such an alignment process may be referred to as surface-mediated optical alignment.

In one embodiment, after the LCs or RMs in the birefringent medium have been aligned by the graphical recording medium layer 410, the birefringent medium may be heat-treated in a temperature range that corresponds to the nematic columns of the LCs or RMs in the birefringent medium to enhance the alignment of the LCs and/or RMs. This process may be referred to as post-exposure thermal treatment. In some embodiments, the process of heat treating the birefringent medium may be omitted.

In one embodiment, when the birefringent medium includes a polymerizable LC, after the RMs are aligned by the patterned recording medium layer 410, the RMs may be polymerized, e.g., thermally polymerized or photopolymerized, to cure and stabilize the directional pattern of the optical axes of the birefringent medium, thereby forming the birefringent medium layer 415.

In one embodiment, the birefringent medium may be irradiated with, for example, UV light 444, as shown in FIG. 4D. Under sufficient UV irradiation, the birefringent medium may undergo polymerization, thereby stabilizing the optical axis direction map of the birefringent medium. In one embodiment, the polymerization of the birefringent medium under UV irradiation may be carried out in air, in an inert atmosphere formed, for example, by nitrogen, argon, carbon dioxide, or in a vacuum. Thus, a polarization-selective grating 400 can be obtained based on a polarization interference exposure process and surface-mediated optical alignment.

As shown in FIG. 4D, the substrate 405 and/or the recording media layer 410 may be used to fabricate, store, or transport the polarization selective grating 400. in one embodiment, the substrate 405 and/or the recording media layer 410 may be removable or detachable from other portions of the polarization selective grating 400 after the other portions of the polarization selective grating 400 are fabricated or transported to another location or device. That is, the substrate 405 and/or the patterned recording medium layer 410 may be used for fabrication, transport, and/or storage to support the birefringent medium layer 415 and may be detachable or removable from the birefringent medium layer 415 when fabrication of the polarization selective grating 400 is complete, or when the polarization selective grating 400 is to be implemented in an optical device.

The manufacturing process is shown in FIG. 5. As shown in FIG. 5A, two substrates 405 and 405 ' (referred to as the first substrate 405 and the second substrate 405 ') may be assembled to form the LC cell 500. for example, the two substrates 405 and 405' may be bonded to each other by an adhesive 412 to form the LC cell 500.

At least one of the two substrates 405 and 405 ' may have one or more conductive electrode layers and a patterned recording medium layer. For example, two electrically conductive electrode layers 540 and 540' may be formed on opposite surfaces of the substrates 405 and 405', and two patterned recording medium layers 410 and 410' may be formed on opposite surfaces of the two electrically conductive electrode layers 540 and 540' .

The conductive electrode layer 540 or 540 ' may be transmissive and/or reflective at least in the same spectral band as the substrate 405 or 405 '. Said conductive electrode layer 540 or 540 ' may be a planar continuous electrode layer or a patterned electrode layer. As shown in FIG. 5A, a gap or space may exist between the patterned recording medium layers 410 and 410′.

As shown in FIG. 5B, an active LC reorientable by an external field may be filled into a space formed between the patterned recording medium layers 410 and 410' within the LC cell 500 to form the active LC layer 505.The patterned recording medium layer 410 or 410 ' may serve as a PAM layer filled into the LC cell 500 with the active LC. PAM layer of the LC such that the active LC may be at least partially aligned by the patterned recording medium layer 410 or 410 ' in a raster pattern to form the active LC layer 505.

Accordingly, the patterned recording medium layers 410 or 410 ' may be referred to as PAM layers 410 and 410 '. The LC cell 500 filled with an active LC may be sealed by, for example, an adhesive 412, and an active PSOE 510 may be obtained. the active PSOE 510 may be switched by a voltage applied to the conductive electrode layers 540 and 540 ' .

The patterned recording media layers 410 and 410 may be provided on opposing inner surfaces of the two substrates 405 and 405 '. In one embodiment, each of the PAM layers 410 and 410 disposed on the two substrates 405 and 405 may be configured to provide planar alignment.

The PAM layers 410 and 410 ' may provide parallel or anti-parallel surface alignment. In one embodiment, the PAM layers 410 and 410 ' set on the two substrates 405 and 405 may be configured to provide mixed surface alignment. For example, the PAM layer 410 disposed at the substrate 405 may be configured to provide planar alignment, and the PAM layer 410 disposed at the other substrate 405 may be configured to provide isotropic alignment.

The conductive electrode layers 540 and 540′ may be provided at the two substrates 405 and 405′. The conductive electrode layers 540 or 540 ' may be provided between a patterned recording medium layer (410 or 410 ') and a substrate (405 or 405 '). In 5A and 5B, each of the conductive electrode layers 540 and 540 ' may be a continuous planar electrode layer. A driving voltage may be applied to the conductive electrode layers 540 and 540 ' to generate a perpendicular electric field to reorient the LC molecules, thereby switching the optical properties of the active PSOE 510. As shown in FIG. 5B, the conductive electrode layers 540 and 540′ may be provided on both sides of the active LC layer 505.

In one embodiment, two conductive electrode layers 540 and 540 ' may be provided on the same side of the active LC layer 505. For example, two substrates 405 and 405' may be assembled to form the LC cell 520 as shown in FIG. 5C. one substrate 405' may be provided without the conductive electrode layer, while the other substrate 405 may be provided with two conductive electrode layers and an electrically insulating layer 560 provided between the two conductive electrode layers.

In other words, the two conductive electrode layers 540a and 540b may be provided on the same side of the active LC layer 505. The two conductive electrode layers 540a and 540b may be a continuous planar electrode layer 540a and a patterned electrode layer 540b. said patterned electrode layer 540b may comprise a plurality of striped electrodes arranged in parallel in a staggered manner.

The active PSOE 525 can be obtained after the LC cell 520 is filled with active LC to form the active LC layer 505. a voltage can be applied between the continuous planar electrode layer 540a and the pictorial electrode layer 540b provided on the same side of the active LC layer 505 to generate a horizontal electric field to reorient the LC molecules, thereby switching the optical properties of the prepared active PSOE 525.

As shown in FIG. 5D, two substrates 405 and 405' may be assembled to form LC cell 570. one substrate 405') may be provided without a conductive electrode layer, while the other substrate 405 may be provided with a conductive electrode layer 580. the conductive electrode layer 580 may comprise an interfering electrode, which may comprise two separately addressable inter-fingered comb electrode structures 541 and 542.

The active PSOE 575 can be obtained after the LC cell 560 is filled with active LC to form the active LC layer 505.A voltage can be applied between the inter-finger comb electrode structures 541 and 542 disposed on the same side of the active LC layer 505 to generate a horizontal electric field to reorient the LC molecules in the active LC layer 505, thereby switching the optical properties.

In one embodiment, the recording medium layer may not be optically patterned before the LC unit is assembled. Instead, the recording medium layer may be optically patterned after the LC units are assembled. For example, two substrates 405 and 405' may be assembled to form the LC unit. At least one of the two substrates 405 and 405' may have one or more conductive electrode layers and a recording medium layer. The LC units may then be exposed to a polarized interferogram.

Accordingly, the recording medium layer provided on the substrate can be optically patterned to provide alignment patterning corresponding to grating patterning. After the LC cell is filled with active LC and sealed, an active PSOE can be obtained (.

FIGS. 6A and 6B illustrate methods of fabricating a PSOE for another embodiment. FIG. 5 may be an active PSOE, while 6A and 6B may be passive PSOEs.

Similar to the embodiment shown in FIG. 5. 6A and 6B may include dispensing a recording medium on a surface of the substrate 605 to form a recording medium layer 620. said recording medium may be a polarization sensitive recording medium. The recording medium may include an optically recordable and polarization-sensitive material configured to have photo-optical anisotropy when exposed to polarized light irradiation. Under polarized light irradiation, molecules and/or photoproducts of the optically recordable and polarization-sensitive material may produce an anisotropic angular distribution in the membrane plane of the recording medium layer.

After the recording medium layer 620 is formed on the substrate 605, the recording medium layer 620 may be exposed to polarized interference patterns generated based on the two recording beams 640 and 642, as shown in FIG. 6B. The two recording beams 640 and 642 may be two coherent circularly polarized beams having opposite rotations.

In one embodiment, said recording medium layer 620 may be optically patterned when said recording medium layer 620 is exposed to polarized interferograms generated during said polarized interferometric exposure process based on said two recording beams 640 and 642. During the polarization interference exposure process, an optical axis direction pattern of the recording medium layer 620 in the exposure area may be defined.

Said recording medium may comprise a photosensitive polymer. The photosensitive polymer molecules may include one or more polarization-sensitive light-responsive groups embedded in the main polymer chain or side polymer chains. During polarization interference exposure of the recording medium layer 620, optical alignment of the polarization-sensitive photoreactive moieties may occur within the volume of the recording medium layer 620. That is, a three-dimensional polarization field generated by the interface of the two recording beams 640 and 642 may be recorded directly within the volume of the recording medium layer 620.

This alignment process as shown in FIG. 6B may be referred to as body-mediated photoalignment. The in-plane oriented pattern of the optical axis may be recorded directly in the recording medium layer 620 by the body-mediated optical alignment in the exposed region. In one embodiment, the in-plane orientation pattern of the optical axis may correspond to a grating pattern.

In one embodiment, the photosensitive polymer included in the recording medium layer 620 may include an amorphous polymer, an LC polymer, and the like. The molecules of the photosensitive polymer may include one or more polarization-sensitive light-responsive groups embedded in the main polymer chains or side polymer chains.

In one embodiment, the polarization-sensitive photoresponsive moiety may include an azobenzene moiety, a cinnamic acid moiety, or a coumarin moiety, among others. In some embodiments, the photosensitive polymer may be an amorphous polymer that may be initially optically isotropic prior to undergoing a polarization interference exposure process and may exhibit induced optical anisotropy after undergoing a polarization interference exposure process.

In one embodiment, the photosensitive polymer may be an LC polymer in which birefringence and in-plane orientation patterns may be recorded due to the effects of photo-optical anisotropy.

In one embodiment, the photosensitive polymer may be an LC polymer with polarization-sensitive cinnamic acid groups embedded in the side polymer chains. An example of an LC polymer with polarization-sensitive cinnamic acid groups embedded in the side polymer chains is LC polymer M1. LC polymer M1 has a nematic intermediate phase in the temperature range from about 65°c to about 400°c, and the optical anisotropy can be induced by irradiating a film of LC polymer M1 with polarized UV light.

In one embodiment, said induced optical anisotropy may subsequently be increased by more than one order of magnitude by annealing said patterned recording medium layer 620 at a temperature in the range of about 65°C to about 400°C.

The substrate 605 may be similar to the substrate 405. in one embodiment, the substrate 605 may be used to fabricate, store, or transport the PSOE 600. after the PSOE 600 has been fabricated or transported to another location or device, the substrate 605 may be removable or detachable from the PSOE 600. In other words, the substrate 605 may be used to fabricate, transport, and/or store to support the PSOE 600 provided by the substrate 605 and may be detachable or removable from the PSOE 600 when the fabrication of the PSOE 600 is complete or when the PSOE 600 is to be implemented in an optical device.

FIG. 10 illustrates a system 1000 configured to generate a polarized interference pattern that can be recorded in a recording medium layer 1010. as shown in FIG. 10, said system 1000 may include a light source 1001, a beam conditioning device 1003, and an SRG 1011.

The beam conditioning device 1003 may include a first lens 1003a, a pinhole aperture 1003c, and a second lens 1003b disposed in an optical series.For example, the beam conditioning device 1003 may be configured to condition a light beam S1022 emitted from the light source 1001 and output a collimated light beam S1026 having a predetermined beam size and a predetermined polarization.

The SRG 1011 may be oriented relative to the optical axis of the beam conditioning device 1003 or the direction of propagation of the light beam S1026 such that the light beam S1026 may be incident on the SRG 1011 at a predetermined angle of incidence. In one embodiment, said system 1000 may comprise a movable platform, the movable platform may be configured to translate and/or rotate the SRG 1011 so as to adjust the orientation and/or position of the SRG 1011 with respect to the propagation direction of the light beam S1026. When the orientation and/or position of the SRG 1011 is adjusted, the angle of incidence of the light beam S1026 relative to the SRG 1011 may be adjusted.

The SRG 1011 may be configured to operate in a Littrow configuration for the light beam S1026 having an angle of incidence and a wavelength.The SRG 1011 may be configured to diffract the light beam S1026 substantially uniformly forward into two paths.

In one embodiment, the first beam S1032 and the second beam S1033 may be a -1st order diffracted beam S1032 and a 0th order diffracted beam S1033, respectively.In one embodiment, the -1st order diffracted beam S1032 and the 0th order diffracted beam S1033 may be two linearly polarized beams having orthogonal polarizations. In one embodiment, the -1st order diffracted beam S1032 and the 0th order diffracted beam S1033 may be two line-polarized beams having substantially the same polarization. In an embodiment, the -1st order diffracted beam S1032 and the 0th order diffracted beam S1033 may have substantially the same light intensity. In one embodiment, the -1st order diffracted beam S1032 and the 0th order diffracted beam S1033 may have different light intensities. The diffraction angles of the -1st order diffracted beam S1032 and the 0th order diffracted beam S1033 may have substantially the same value and opposite sign.

The system 1000 may include one or more reflectors 1015a and 1015b configured to change the direction of propagation of the first light beam S1032 by reflecting the first light beam S1032 in different directions. The combination of reflectors 1015a and 1015b may add multiple turns in the first path such that the first light beam S1032 propagates in a direction substantially perpendicular to the propagation direction of the second light beam S1033 traveling in the second path. That is, the direction of the first path may be altered by the reflectors 1015a and 1015b such that the first path is perpendicular to the second path at the unpolarized beam splitter 1019.

The system 1000 may include a first waveplate 1013a disposed in a first path along which the first beam S1032 propagates, and a second waveplate 1013b disposed in a second path along which the second beam S1033 propagates.The first waveplate 1013a and the second waveplate 1013b may be configured to convert the first beam S1032 and the second beam S1033, respectively, to a circularly polarized beam having an orthogonally polarized circularly polarized beams.

The polarization axis of said first waveplate 1013a may be oriented with respect to the direction of polarization of said first beam S1032 to convert said first beam S1032 into a circularly polarized beam S1036 having a first chirality. the beam S1036 may be a collimated beam having a plane wavefront. The polarization axis of the second wavefront 1013b may be oriented relative to the direction of polarization of the second beam S1033 to convert the second beam S1033 into a circularly polarized beam S1035 having a second handedness opposite to the first beam.

In one embodiment, the system 1000 may include a third lens 1017 disposed in a second path between the second waveplate 1013b and the recoding medium layer 1010. the light beam S1035 may be transmitted through the third lens 1017 as a light beam S1037 having a parabolic wavefront.

In one embodiment, the distance between the second waveplate 1013b and the recoding medium layer 1010 may be approximately twice the focal length of the third lens 1017. In one embodiment, the non-polarized beam splitter 1019 may be provided in a second path between the third lens 1017 and the recoding medium layer 1010. The NPBS 1019 may be configured to combine a first beam S1032 propagating along the first path and a beam S1033 propagating along the second path.

For example, the NPBS 1019 may be configured to substantially transmit the wave beam S1037 as a wave beam S1039 propagating in the +z-axis direction and substantially reflect the wave beam S1036 propagating in the +y-axis direction as a wave beam S1038 propagating in the +z-axis direction. The wave beam S1039 and the wave beam S1038 output from the NPBS 1019 may interfere with each other to produce a polarization interferogram which may be recorded in the recording medium layer 1010. After sufficient exposure, the polarization interference pattern may be recorded in the recording medium layer 1010 to define an optical axis direction pattern of the recording medium layer 1010.

In one embodiment, the direction of the optical axis of the recording medium layer 1010 may vary spatially in at least one in-plane direction having different spacing. The pattern of the direction of the optical axis of the recording medium layer 1010 may correspond to a lens pattern. A polarization-selective lens may be fabricated based on the exposed recording medium layer 1010.

For example, the exposed recording medium layer 1010 may function as a polarization selective lens. In one embodiment, a birefringent medium may be arranged on the exposed recording medium layer 1010. Optically anisotropic molecules in the birefringent medium may be at least partially arranged by the exposed recording medium layer 1010 according to the lens pattern.

In one embodiment, the birefringent medium arranged on the exposed recording medium layer 1010 may be further polymerized. The polymerized birefringent medium may form a passive polarization selective lens.

In one embodiment, two substrates having said exposed recording medium layer 1010 may be aligned in parallel to form cells with spaces. The birefringent medium may fill the spaces of the cells.

In one embodiment, at least one of the two substrates may include two electrodes configured to provide a drive voltage to the birefringent medium. The cell filled with the birefringent medium may act as an active polarization selective lens.

名为“System and method for fabricating polarization selective element”的Meta专利申请最初在2020年11月提交，并在日前由美国专利商标局公布。

Generally speaking, after a U.S. patent application is examined, it will be automatically published 18 months from the filing date or priority date, or it will be published within 18 months from the filing date at the request of the applicant. Note that publication of a patent application does not mean that the patent is approved. After a patent application is filed, the USPTO requires actual review, which can take anywhere from 1 to 3 years.

In addition, this is only a patent application, which does not necessarily mean that it will be adopted, and it is also uncertain whether it will be actually commercialized and the actual results of its application.