Patent Application
20240280725
The present disclosure belongs to the technical field of optical imaging elements, and in particular to, an optical imaging element with magnetic reflective layer imaging units and a preparation method thereof.
In recent years, with the rapid development of advanced technologies such as aerospace technology, photoelectric technology, atomic energy technology, and laser technology, related performances of optical elements are required increasingly. In the high-tech fields, the optical elements are widely used, but the surface quality of the optical elements is highly required. However, the resolution and clarity of aerial imaging of a micro-channel matrix optical waveguide slab realized by two orthogonal transparent materials adopted currently are not enough, which not only affects the user experience, but also puts forward higher requirements for application scenarios, resulting in great constraints on the commercial promotion and large-scale application of dielectric-free aerial imaging technology.
Aiming at the above-mentioned defects, the present disclosure provides an optical imaging element with magnetic reflective layer imaging units and a preparation method thereof, where a binary magneto-optical photonic crystal with a modular structure can be formed, or a ternary magneto-optical photonic crystal structure can be formed when a plurality of optical imaging units including upper light-transmitting laminates and lower light-transmitting laminates are stacked, a non-reciprocal effect at an edge of a band gap is maximized, a magneto-optical isolator function is realized by using a non-reciprocal phase shift region, and the non-reciprocal phase shift region can be realized without a large thickness, thereby reducing the light loss, improving the refraction imaging accuracy, realizing a photonic band gap by using a central magnetic layer with a large dielectric constant of the reflective layer, and suppressing the spontaneous emission of molecules or atoms with optical frequency falling in the band gap.
The present disclosure provides the following technical solutions: An optical imaging element with magnetic reflective layer imaging units is provided. The optical imaging element includes a plurality of superimposed optical imaging units. The optical imaging unit includes an upper light-transmitting laminate and a lower light-transmitting laminate. The upper light-transmitting laminate and the lower light-transmitting laminate have the same structure composed of a plurality of light-transmitting strips with reflective layers in parallel. The direction of a first light-transmitting strip in the upper light-transmitting laminate is vertically intersected with the direction of a second light-transmitting strip in the lower light-transmitting laminate.
The reflective layer is a sandwich laminated metal magnetic thin layer. The sandwich laminated metal magnetic thin layer includes a first metal aluminum layer, a central magnetic layer, and a second metal aluminum layer. The central magnetic layer is sandwiched between the first metal aluminum layer and the second metal aluminum layer. The sandwich laminated metal magnetic thin layer is bonded to the light-transmitting strip by magnetron sputtering. The central magnetic layer is a Fe3O4 magnetic thin layer or a neodymium-iron-boron magnetic thin layer. The neodymium-iron-boron magnetic thin layer has a thickness of 0.05-0.2 mm. The Fe3O4 magnetic thin layer has a thickness of 0.05-0.2 μm.
Further, the upper light-transmitting laminate and the lower light-transmitting laminate are cured and adhered by a transparent optical adhesive. The plurality of superimposed optical imaging units are cured and adhered by the transparent optical adhesive.
Further, the plurality of light-transmitting strips with reflective layers are cured and adhered by a transparent optical adhesive.
Further, raw materials for preparing the transparent optical adhesive include the following components in parts by weight:
Further, a preparation method of the transparent optical adhesive includes the following steps:
Further, the light-transmitting strips are thin glass or acrylic plates.
Further, the light-transmitting strips have a thickness of 0.1-0.3 mm in a vertical longitudinal direction.
Further, a molecular formula of a neodymium-iron-boron magnetic material contained in the neodymium-iron-boron magnetic thin layer is NdFeB, NdXFe94−xB6, Nd1+yFe4B4, or NdzFe77B23−z, where x=7, 8, 9, or 10, y=1 or 2, 5≤z≤15, and z is an integer.
Further, a preparation method for the light-transmitting strips with the reflective layers includes the following steps:
The present disclosure also provides a preparation method of the optical imaging element, including the following steps:
The beneficial effects of the present disclosure are as follows:
1. According to the optical imaging element provided by the present disclosure, a plurality of first light-transmitting strips arranged in parallel of an upper light-transmitting laminate and a plurality of second light-transmitting strips arranged in parallel of a lower light-transmitting laminate in a plane where the optical imaging element is located are perpendicular in a horizontal direction of the plane to form a binary magneto-optical photonic crystal with a modular structure, or form a ternary magneto-optical photonic crystal structure when a plurality of optical imaging units including upper light-transmitting laminates and lower light-transmitting laminates are stacked. A non-reciprocal effect at an edge of a band gap is maximized, a magneto-optical isolator function is realized by using a non-reciprocal phase shift region, and the non-reciprocal phase shift region can be realized without a large thickness. Because of the non-reciprocal effect, transmission peaks of forward transmission and reverse transmission of defect modes are separated, and the frequency spacing between the transmission peaks can realize the isolator function.
2. A first metal aluminum layer, a central magnetic layer, and a second metal aluminum layer are arranged, and a sandwich laminated metal magnetic thin layer is used for limiting light in a vertical direction. A magnetic reflective layer is arranged on one side of the light-transmitting strip. The central magnetic layer having Fe3O4 or neodymium-iron-boron magnetic thin layers arranged between the two metal aluminum layers is prepared by magnetron sputtering, so that the dielectric constant is improved, and then the refractive index is reduced. Since the effective refractive index of the reflective layer is lower than that of a transparent plate, the light is limited in the vertical direction, and a light wave has extremely low insertion loss when propagating in a forward direction, but has great attenuation or reflection when propagating in a reverse direction, which is irreversible, thereby eliminating the influence of reflected light or scattered light on an optical system in an optical path and reducing the light loss.
3. A transparent optical curing agent is used for curing and adhering a plurality of optical imaging units and light-transmitting strips of the upper light-transmitting laminate or the lower light-transmitting laminate. Nanometer ZrO2 is added into the curing agent. Nanometer ZrO2, as a typical P-type semiconductor material, not only has high refractive index (2.3-2.4), but also has a wide band gap (7.8 eV), and has low photon absorption rate in the wavelength range of 300-1000 nm. Furthermore, ZrO2 is a hexa-coordinated oxide, which has higher chemical stability and thermal stability. The transparent optical curing agent in the optical imaging element provided by the present disclosure can well control the distribution of nanoparticles in the system by adding ZrO2 and utilizing the interaction between side hydroxyl groups on the molecular chains of each acrylic monomer and nano clusters formed by nanometer ZrO2, and will not cause secondary coalescence due to large-scale wandering, thereby effectively improving the refractive index and light transmittance of the optical imaging element.
4. In the transparent optical curing agent used for curing and adhering optical imaging elements provided by the present disclosure, 4-acryloxybenzophenone is used as an unsaturated photosensitizer, and dodecyl mercaptan is used as a chain transfer agent for mixing reaction with a plurality of acrylic monomers, so that the plurality of acrylic monomers can be effectively amplified, and the spatial form of the finally formed transparent optical curing agent can be changed, thereby ensuring that the refractive index will not be reduced and refraction dislocation, transfer and other phenomena will not occur, ensuring that light will only be refracted twice in a plurality of upper light-transmitting laminates and lower light-transmitting laminates, and will not be refracted in an adhesive curing layer formed by the transparent optical curing agent, resulting in the change of the optical path, thereby avoiding the phenomenon of inaccurate optical path to be refracted finally.
5. The transparent optical curing agent used for curing and adhering optical imaging elements provided by the present disclosure utilizes a gradient heating curing mode of a normal temperature curing system in the preparation process, to ensure that a hybrid system of the plurality of acrylic monomers will not be cured before complete amplification, and that a homogeneous hybrid system after complete hydrolysis can quickly cure and cross-link inorganic nanoparticles in the network under the gradient heating condition, thereby effectively solving the problem of phase separation.
The present disclosure will be described in more detail below based on embodiments and with reference to the accompanying drawings. In the drawings:
The following clearly and completely describes the technical solutions in the embodiments of the present disclosure with reference to the accompanying drawings in the embodiments of the present disclosure. Apparently, the described embodiments are some of the embodiments of the present disclosure rather than all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the disclosed embodiments without creative efforts shall fall within the protection scope of the present disclosure.
It should be noted that the descriptions in the present disclosure relating to “first”, “second” and the like are for descriptive purposes only and cannot be construed as indicating or implying their relative importance or implying the number of technical features indicated. Therefore, a feature restricted by “first” or “second” may explicitly indicate or implicitly include at least one of such features. In addition, technical solutions between the embodiments may be combined with each other, provided that the combination of the technical solutions can be implemented by a person of ordinary skill in the art. When the combined technical solutions conflict with each other or cannot be implemented, it should be considered that such a combination of the technical solutions does not exist or is not within the protection scope of this application.
Secondly, in the embodiments of the present disclosure, all directivity indications (such as up, down, left, right, front, and back) are only used to explain the relative positional relationship, movement situation, etc. among the components under a certain posture (as shown in the drawing). If the specific posture changes, the directivity indications will change accordingly, and the connection may be direct connection or indirect connection.
As shown in
The reflective layer 3 is a sandwich laminated metal magnetic thin layer. The sandwich laminated metal magnetic thin layer 3 includes a first metal aluminum layer 31, a central magnetic layer 32, and a second metal aluminum layer 33. The central magnetic layer 32 is sandwiched between the first metal aluminum layer 31 and the second metal aluminum layer 33. The sandwich laminated metal magnetic thin layer is bonded to the light-transmitting strip 4 by magnetron sputtering. The central magnetic layer 32 is a Fe3O4 magnetic thin layer. The Fe3O4 magnetic thin layer has a thickness of 0.05-0.2 μm. The thickness of the Fe3O4 magnetic thin layer may be selected in this range according to an actual optical refraction effect to be achieved, and may be 0.05 μm, 0.10 μm, 0.2 μm, or the like.
This embodiment provides an optical imaging element with magnetic reflective layer imaging units. The optical imaging element includes two superimposed optical imaging units. The optical imaging unit includes an upper light-transmitting laminate 1 and a lower light-transmitting laminate 2. The upper light-transmitting laminate 1 and the lower light-transmitting laminate 2 have the same structure composed of a plurality of light-transmitting strips 4 with reflective layers 3 in parallel. The direction of a first light-transmitting strip 41 in the upper light-transmitting laminate 1 is vertically intersected with the direction of a second light-transmitting strip 42 in the lower light-transmitting laminate 2.
The reflective layer 3 is a sandwich laminated metal magnetic thin layer. The sandwich laminated metal magnetic thin layer 3 includes a first metal aluminum layer 31, a central magnetic layer 32, and a second metal aluminum layer 33. The central magnetic layer 32 is sandwiched between the first metal aluminum layer 31 and the second metal aluminum layer 33. The sandwich laminated metal magnetic thin layer is bonded to the light-transmitting strip 4 by magnetron sputtering. The central magnetic layer 32 is a neodymium-iron-boron magnetic thin layer. A molecular formula of a neodymium-iron-boron magnetic material contained in the neodymium-iron-boron magnetic thin layer is NdFeB, NdXFe94−xB6. The size of x may be selected according to an actual optical refraction effect to be achieved, and may be 7, 8, 9, or 10. The neodymium-iron-boron magnetic thin layer has a thickness of 0.05 mm.
This embodiment provides an optical imaging element with magnetic reflective layer imaging units. The optical imaging element includes five superimposed optical imaging units. The optical imaging unit includes an upper light-transmitting laminate 1 and a lower light-transmitting laminate 2. The upper light-transmitting laminate 1 and the lower light-transmitting laminate 2 have the same structure composed of a plurality of light-transmitting strips 4 with reflective layers 3 in parallel. The direction of a first light-transmitting strip 41 in the upper light-transmitting laminate 1 is vertically intersected with the direction of a second light-transmitting strip 42 in the lower light-transmitting laminate 2.
The reflective layer 3 is a sandwich laminated metal magnetic thin layer. The sandwich laminated metal magnetic thin layer 3 includes a first metal aluminum layer 31, a central magnetic layer 32, and a second metal aluminum layer 33. The central magnetic layer 32 is sandwiched between the first metal aluminum layer 31 and the second metal aluminum layer 33. The sandwich laminated metal magnetic thin layer is bonded to the light-transmitting strip 4 by magnetron sputtering. The central magnetic layer 32 is a neodymium-iron-boron magnetic thin layer. A molecular formula of a neodymium-iron-boron magnetic material contained in the neodymium-iron-boron magnetic thin layer is Nd1+yFe4B4, where 0<y≤2, and y is 1 or 2. That is, the molecular formula of the neodymium-iron-boron magnetic material contained in the neodymium-iron-boron magnetic thin layer is Nd2Fe4B4 or Nd3Fe4B4. The neodymium-iron-boron magnetic thin layer has a thickness of 0.15 mm.
It should be noted that in Embodiments 1-3 provided by the present disclosure, the number of optical imaging units superimposed into the optical imaging element is not limited to one, two, or five, and the optical imaging units may be selectively superimposed according to actual optical refraction and imaging requirements to be achieved.
Embodiment 1 differs from Embodiment 2 or 3 only in that the molecular formula of the neodymium-iron-boron magnetic material contained in the neodymium-iron-boron magnetic thin layer is NdFeB, and the neodymium-iron-boron magnetic thin layer has a thickness of 0.08 mm.
Embodiment 1 differs from Embodiment 2 or 3 only in that the molecular formula of the neodymium-iron-boron magnetic material contained in the neodymium-iron-boron magnetic thin layer is NdzFe77B23−z, where 5≤z≤15. The size of z may be selected in this range according to an actual optical refraction effect to be achieved, and may be 5, 8, 10, 12, or 15. The neodymium-iron-boron magnetic thin layer has a thickness of 0.2 mm.
As shown in
On the basis of Embodiments 1-5, in the optical imaging element prepared in each embodiment, the plurality of light-transmitting strips with reflective layers are cured and adhered by a transparent optical adhesive in the optical imaging element with magnetic reflective layer imaging units according to claim 1.
Raw materials for preparing the transparent optical adhesive adopted in Embodiments 6 and 7 of the present disclosure include the following components in parts by weight:
A preparation method of the transparent optical adhesive includes the following steps:
1) Preheat 5 parts of 2-ethylhexyl acrylate, 1.67 parts of butyl acrylate, 1.67 parts of methyl methacrylate, 3.33 parts of glycidyl methacrylate, 2.67 parts of tripropylene glycol diacrylate, 30 parts of ethyl acetate, and 0.17 parts of azobisisobutyronitrile at 80° C. for 20 min to form a prepolymer mixture.
2) Add the parts by weight of ZrO2 to the uncooled prepolymer mixture obtained in step 1), and stir for 15-20 min at a revolving speed of 200-300 rpm.
3) Heat remaining 10 parts of 2-ethylhexyl acrylate, remaining 3.33 parts of butyl acrylate, remaining 3.33 parts of methyl methacrylate, remaining 6.67 parts of glycidyl methacrylate, remaining 5.33 parts of tripropylene glycol diacrylate, and remaining 0.33 parts of azobisisobutyronitrile at 80° C. for 20 min, stir continuously during the heating process, mix the obtained mixture with the mixture obtained in step 2) and 3 parts of 4-acryloxy benzophenone, and heat and stir continuously for 45-60 min at a revolving speed of 150 rpm at 70° C.
4) Heat to 150° C. at a heating rate of 5° C./min under a nitrogen purging environment with a flow rate of 5 cm2/min, stir for 2 h in the state of heat preservation, cool to 80° C. and stir continuously for 1 h, and then cool to room temperature, to obtain the transparent optical adhesive.
Through experiments, the transparent optical curing agent provided in this embodiment has a light transmittance of 87.7% in a wavelength range of 200-800 cm and a refractive index of 0.89 in a test wavelength range of 600-650 nm, which shows that the transparent optical curing agent provided in this embodiment has good light transmittance and is not easy to cause unnecessary light refraction.
5 g of the transparent optical curing agent was weighed by a differential scanning calorimeter, and the temperature was raised from −25° C. to 200° C. in nitrogen atmosphere, and the heating rate was 10° C./min. The thermal performance of the curing agent in this embodiment was detected, and the actual residual amount after thermogravimetric loss was 89.6%, which showed a good thermal stability.
Raw materials for preparing the transparent optical adhesive adopted in Embodiments 6 and 7 of the present disclosure include the following components in parts by weight:
A preparation method of the transparent optical adhesive includes the following steps:
1) Preheat 6.7 parts of 2-ethylhexyl acrylate, 2.2 parts of butyl acrylate, 2.13 parts of methyl methacrylate, 4 parts of glycidyl methacrylate, 3.3 parts of tripropylene glycol diacrylate, 38 parts of ethyl acetate, and 0.25 parts of azobisisobutyronitrile at 85° C. for 25 min to form a prepolymer mixture.
2) Add 30 parts of ZrO2 to the uncooled prepolymer mixture obtained in step 1), and stir for 18 min at a revolving speed of 250 rpm.
3) Heat remaining 13.3 parts of 2-ethylhexyl acrylate, remaining 4.4 parts of butyl acrylate, remaining 4.27 parts of methyl methacrylate, remaining 8 parts of glycidyl methacrylate, remaining 6.7 parts of tripropylene glycol diacrylate, and remaining 0.5 parts of azobisisobutyronitrile at 85° C. for 25 min, stir continuously during the heating process, mix the obtained mixture with the mixture obtained in step 2) and the parts by weight of 4-acryloxy benzophenone, and heat and stir continuously for 45-60 min at a revolving speed of 200 rpm at 80° C.
4) Heat to 165° C. at a heating rate of 8° C./min under a nitrogen purging environment with a flow rate of 8 cm2/min, stir for 2.5 h in the state of heat preservation, cool to 80° C. and stir continuously for 1 h, and then cool to room temperature, to obtain the transparent optical adhesive.
Through experiments, the transparent optical curing agent provided in this embodiment has a light transmittance of 90.8% in a wavelength range of 200-800 cm and a refractive index of 0.74 in a test wavelength range of 600-650 nm, which shows that the transparent optical curing agent provided in this embodiment has good light transmittance and is not easy to cause unnecessary light refraction.
5 g of the transparent optical curing agent was weighed by a differential scanning calorimeter, and the temperature was raised from −25° C. to 200° C. in nitrogen atmosphere, and the heating rate was 10° C./min. The thermal performance of the curing agent in this embodiment was detected, and the actual residual amount after thermogravimetric loss was 91.3%, which showed a good thermal stability.
Raw materials for preparing the transparent optical adhesive adopted in Embodiments 6 and 7 of the present disclosure include the following components in parts by weight:
A preparation method of the transparent optical adhesive includes the following steps:
1) Preheat 8.33 parts of 2-ethylhexyl acrylate, 2.67 parts of butyl acrylate, 2.67 parts of methyl methacrylate, 5 parts of glycidyl methacrylate, 4 parts of tripropylene glycol diacrylate, 45 parts of ethyl acetate, and 0.33 parts of azobisisobutyronitrile at 90° C. for 30 min to form a prepolymer mixture.
2) Add 40 parts of ZrO2 to the uncooled prepolymer mixture obtained in step 1), and stir for 20 min at a revolving speed of 300 rpm.
3) Heat remaining 16.67 parts of 2-ethylhexyl acrylate, remaining 5.33 parts of butyl acrylate, remaining 5.33 parts of methyl methacrylate, remaining 10 parts of glycidyl methacrylate, remaining 8 parts of tripropylene glycol diacrylate, and remaining 0.67 parts of azobisisobutyronitrile at 90° C. for 30 min, stir continuously during the heating process, mix the obtained mixture with the mixture obtained in step 2) and the parts by weight of 4-acryloxy benzophenone, and heat and stir continuously for 60 min at a revolving speed of 1250 rpm at 85° C.
4) Heat to 180° C. at a heating rate of 10° C./min under a nitrogen purging environment with a flow rate of 10 cm2/min, stir for 3 h in the state of heat preservation, cool to 80° C. and stir continuously for 1 h, and then cool to room temperature, to obtain the transparent optical adhesive.
Through experiments, the transparent optical curing agent provided in this embodiment has a light transmittance of 93.5% in a wavelength range of 200-800 cm and a refractive index of 0.66 in a test wavelength range of 600-650 nm, which shows that the transparent optical curing agent provided in this embodiment has good light transmittance and is not easy to cause unnecessary light refraction.
5 g of the transparent optical curing agent was weighed by a differential scanning calorimeter, and the temperature was raised from −25° C. to 200° C. in nitrogen atmosphere, and the heating rate was 10° C./min. The thermal performance of the curing agent in this embodiment was detected, and the actual residual amount after thermogravimetric loss was 92.1%, which showed a good thermal stability.
A preparation method for the light-transmitting strips with the reflective layers 3 in which the central magnetic layer of the reflective layer 3 is a Fe3O4 magnetic thin layer includes the following steps:
M1: Take a light-transmitting strip plate as a substrate, soak the substrate with detergent for 10-20 min, preferably 15 min, ultrasonically clean the substrate for 10-20 min (preferably 15 min), adopt a mixed solution of anhydrous ethanol and acetone with a volume ratio of 4:7, continuously ultrasonically clean the substrate for 15-30 min (preferably 20 min), and then dry the substrate for later use.
M2: Spray Al powder on the substrate by a sprayer to form the first metal aluminum layer.
Single target magnetron sputtering equipment is adopted when the central magnetic layer is the Fe3O4 magnetic thin layer. A distance between targets and the substrate is set to 80-100 mm (preferably 90 mm). Argon is filled, a sputtering power of a single target is adjusted to 135 W for sputtering, and the central magnetic layer is formed after sputtering. After magnetron sputtering of the Fe3O4 magnetic thin layer, the Al powder is continuously sprayed on the Fe3O4 magnetic thin layer by the sprayer to form the second metal aluminum layer.
A gas pressure of the sputtering argon is adjusted to 0.3-0.5 Pa (preferably 0.4 Pa) and a revolving speed of the substrate is adjusted to 50-60 rpm (preferably 55 rpm) during the sputtering process, and plate-shaped materials with the reflective layers (3) of the light-transmitting strips 4 formed from the substrate are finally formed.
M3: Cut the plate-shaped materials obtained in step M2 into the light-transmitting strips 4 with the reflective layers 3, having a width of 0.1-0.3 mm (preferably 0.2 mm).
Through experiments, a dielectric constant ε r of the reflective layer prepared by this embodiment is 8.96, which can realize Kerr rotation angle of about 45° and high reflectivity with a center wavelength of about 1 micron. A light wave has extremely low insertion loss when propagating in a forward direction, but has great attenuation or reflection when propagating in a reverse direction, which is irreversible, thereby eliminating the influence of reflected light or scattered light on an optical system in an optical path and reducing the light loss.
A preparation method for the light-transmitting strips 4 with the reflective layers 3 in which the central magnetic layer of the reflective layer 3 is a neodymium-iron-boron magnetic thin layer and a molecular formula of a neodymium-iron-boron magnetic material contained in the neodymium-iron-boron magnetic thin layer is NdxFe94−xB6 (x=7, 8, 9, or 10) includes the following steps:
M1: Take a light-transmitting strip plate as a substrate, soak the substrate with detergent for 10 min, ultrasonically clean the substrate for 20 min, adopt a mixed solution of anhydrous ethanol and acetone with a volume ratio of 4:7, continuously ultrasonically clean the substrate for 15 min, and then dry the substrate for later use.
M2: Spray Al powder on the substrate by a sprayer to form the first metal aluminum layer, adopt a three-target co-sputtering instrument, set an angle between targets and a plane where the substrate is located to 15°, respectively adjust a sputtering power of a first target which is a pure Nd element sputtering target to 20 W, a sputtering power of a second target which is a pure Fe element sputtering target to 70 W, and a sputtering power of a third target which is a pure B element sputtering target to 5 W, to control Nd, Fe, and B elements in the neodymium-iron-boron magnetic thin layer to be x: 94-x: 6 respectively, and after magnetron sputtering of the neodymium-iron-boron magnetic thin layer with a molecular formula of NdxFe94−xB6, continuously spray the Al powder on the neodymium-iron-boron magnetic thin layer with a molecular formula of NdxFe94−xB6 by the sprayer to form the second metal aluminum layer.
A gas pressure of the sputtering argon is adjusted to 0.3 Pa and a revolving speed of the substrate is adjusted to 60 rpm during the sputtering process, and plate-shaped materials with the reflective layers 3 of the light-transmitting strips 4 formed from the substrate are finally formed.
M3: Cut the plate-shaped materials obtained in step M2 into the light-transmitting strips 4 with the reflective layers 3, having a width of 0.1 mm.
Through experiments, a dielectric constant ε r of the reflective layer prepared by this embodiment is 9.04, which can realize Kerr rotation angle of about 45° and high reflectivity with a center wavelength of about 1 micron. A light wave has extremely low insertion loss when propagating in a forward direction, but has great attenuation or reflection when propagating in a reverse direction, which is irreversible, thereby eliminating the influence of reflected light or scattered light on an optical system in an optical path and reducing the light loss.
A preparation method for the light-transmitting strips 4 with the reflective layers 3 in which the central magnetic layer of the reflective layer 3 is a neodymium-iron-boron magnetic thin layer and a molecular formula of a neodymium-iron-boron magnetic material contained in the neodymium-iron-boron magnetic thin layer is Nd1+yFe4B4 (0<y≤2) includes the following steps:
M1: Take a light-transmitting strip plate as a substrate, soak the substrate with detergent for 15 min, ultrasonically clean the substrate for 15 min, adopt a mixed solution of anhydrous ethanol and acetone with a volume ratio of 4:7, continuously ultrasonically clean the substrate for 20 min, and then dry the substrate for later use.
M2: Spray Al powder on the substrate by a sprayer to form the first metal aluminum layer, adopt a three-target co-sputtering instrument, set an angle between targets and a plane where the substrate is located to 20°, respectively adjust a sputtering power of a first target which is a pure Nd element sputtering target to 30 W, a sputtering power of a second target which is a pure Fe element sputtering target to 50 W, and a sputtering power of a third target which is a pure B element sputtering target to 35 W, to control Nd, Fe, and B elements in the neodymium-iron-boron magnetic thin layer to be 1+y:4:4 respectively, and after magnetron sputtering of the neodymium-iron-boron magnetic thin layer with a molecular formula of Nd1+yFe4B4, continuously spray the Al powder on the neodymium-iron-boron magnetic thin layer with a molecular formula of Nd1+yFe4B4 by the sprayer to form the second metal aluminum layer.
A gas pressure of the sputtering argon is adjusted to 0.4 Pa and a revolving speed of the substrate is adjusted to 50-60 rpm during the sputtering process, and plate-shaped materials with the reflective layers 3 of the light-transmitting strips 4 formed from the substrate are finally formed.
M3: Cut the plate-shaped materials obtained in step M2 into the light-transmitting strips 4 with the reflective layers 3, having a width of 0.2 mm.
Through experiments, a dielectric constant ε r of the reflective layer prepared by this embodiment is 9.23, which can realize Kerr rotation angle of about 45° and high reflectivity with a center wavelength of about 1 micron. A light wave has extremely low insertion loss when propagating in a forward direction, but has great attenuation or reflection when propagating in a reverse direction, which is irreversible, thereby eliminating the influence of reflected light or scattered light on an optical system in an optical path and reducing the light loss.
A preparation method for the light-transmitting strips 4 with the reflective layers 3 in which the central magnetic layer of the reflective layer 3 is a neodymium-iron-boron magnetic thin layer and a molecular formula of a neodymium-iron-boron magnetic material contained in the neodymium-iron-boron magnetic thin layer is NdFeB or NdzFe77B23−z (5≤z≤15) includes the following steps:
M1: Take a light-transmitting strip plate as a substrate, soak the substrate with detergent for 20 min, ultrasonically clean the substrate for 10 min, adopt a mixed solution of anhydrous ethanol and acetone with a volume ratio of 4:7, continuously ultrasonically clean the substrate for 30 min, and then dry the substrate for later use.
M2: Spray Al powder on the substrate by a sprayer to form the first metal aluminum layer, adopt a three-target co-sputtering instrument, set an angle between targets and a plane where the substrate is located to 25°, and respectively adjust a sputtering power of a first target which is a pure Nd element sputtering target to 50 W, a sputtering power of a second target which is a pure Fe element sputtering target to 30 W, and a sputtering power of a third target which is a pure B element sputtering target to 5 W, to control Nd, Fe, and B elements in the neodymium-iron-boron magnetic thin layer to be 1:1:1 respectively.
Alternatively, a sputtering power of a first target which is a pure Nd element sputtering target is set to 50 W, a sputtering power of a second target which is a pure Fe element sputtering target is set to 70 W, and a sputtering power of a third target which is a pure B element sputtering target is set to 30 W, to control Nd, Fe, and B elements in the neodymium-iron-boron magnetic thin layer to be z:77:23-z respectively.
After magnetron sputtering of the neodymium-iron-boron magnetic thin layer with a molecular formula of NdFeB or NdzFe77B23−z, the Al powder is continuously sprayed on the central magnetic layer by the sprayer to form the second metal aluminum layer.
A gas pressure of the sputtering argon is adjusted to 0.5 Pa and a revolving speed of the substrate is adjusted to 60 rpm during the sputtering process, and plate-shaped materials with the reflective layers 3 of the light-transmitting strips 4 formed from the substrate are finally formed.
M3: Cut the plate-shaped materials obtained in step M2 into the light-transmitting strips 4 with the reflective layers 3, having a width of 0.3 mm.
Through experiments, a dielectric constant ε r of the reflective layer prepared by this embodiment is 9.36 (the molecular formula of the neodymium-iron-boron magnetic thin layer is NdFeB) or 9.45 (the molecular formula of the neodymium-iron-boron magnetic thin layer is NdzFe77B23−z), which can realize Kerr rotation angle of about 45° and high reflectivity with a center wavelength of about 1 micron. A light wave has extremely low insertion loss when propagating in a forward direction, but has great attenuation or reflection when propagating in a reverse direction, which is irreversible, thereby eliminating the influence of reflected light or scattered light on an optical system in an optical path and reducing the light loss.
The present disclosure also provides a preparation method of the optical imaging element, including the following steps:
S1: Clamp the plurality of light-transmitting strips 4 with the reflective layers 3 by clamps to form a single-layer sheet, and then perform double-sided grinding and polishing on upper and lower surfaces of the single-layer sheet by using a double-sided grinding and polishing disc until the upper and lower surfaces are ground flat and polished bright, to prepare the upper light-transmitting laminate 1 and the lower light-transmitting laminate 2.
S2: Place the upper light-transmitting laminate 1 and the lower light-transmitting laminate 2 in a perpendicular direction within a plane direction of the formed single-layer sheet according to the direction of the first light-transmitting strip 41 in the upper light-transmitting laminate 1 and the direction of the second light-transmitting strip 42 in the lower light-transmitting laminate 2.
S3: Spin-coat the transparent optical adhesive on a lower surface of the upper light-transmitting laminate 1 and an upper surface of the lower light-transmitting laminate 2, and cure and adhere the laminates to form the optical imaging unit.
S4: Cure and adhere the plurality of optical imaging units by the transparent optical adhesive.
The optical imaging element provided by the present disclosure realizes unidirectional transmission in which the transmittance of symmetric/antisymmetric optical signals with a frequency of 0.417 c/a is greater than 90%.
The above embodiments are merely used for describing the technical solutions of the present disclosure, but are not intended to limit the present disclosure. Although the present disclosure is described in detail with reference to the foregoing embodiments, it should be appreciated by a person of ordinary skill in the art that, modifications may still be made to the technical solutions described in the foregoing embodiments, or equivalent replacements may be made to the part or all of the technical features, and these modifications or replacements will not cause the essence of corresponding technical solutions to depart from the scope of the technical solutions in the embodiments of the present disclosure.
Furthermore, a person skilled in the art can understand that, although some embodiments herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the present disclosure and to form different embodiments. For example, in the foregoing claims, any one of the claimed embodiments may be used in any combination. Information of the BACKGROUND section is merely disclosed to increase the understanding of the overall background of the present disclosure, but is not necessarily regarded as acknowledging or suggesting, in any form, that the information constitutes the prior art known to a person of ordinary skill in the art.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202210057106.X | Jan 2022 | CN | national |
This application is a continuation of International Application No. PCT/CN2023/072887, filed on Jan. 18, 2023, which itself claims priority to Chinese Patent Application No. 202210057106.X, filed on Jan. 19, 2022, the disclosures of which are hereby incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2023/072887 | Jan 2023 | WO |
| Child | 18652914 | US |
