Spatial phase modulator and method for producing spatial phase modulator

Abstract

A spatial phase modulator and a method for producing a spatial phase modulator are provided. The spatial phase modulator includes a first substrate and a second substrate that are meshed together, and a liquid crystal layer disposed between the two substrates, where a transparent electrode layer and a first alignment and guiding layer are disposed in a cascading manner on a side that is of the first substrate and that faces the liquid crystal layer; and an electrode layer and an insulation medium glass layer are disposed in a cascading manner on a side that is of the second substrate and that faces the liquid crystal layer, where the insulation medium glass layer has an inclined serration structure on a side facing the liquid crystal layer.

Claims

1. A spatial phase modulator, comprising: a first substrate and an opposing second substrate, and a liquid crystal layer disposed between the first substrate and the second substrate, wherein a transparent electrode layer and a first alignment and guiding layer are disposed in a cascading manner, in a direction in which the first substrate faces the second substrate, on a side that is of the first substrate and that faces the liquid crystal layer; wherein an aluminized electrode layer and an insulation medium glass layer are disposed in a cascading manner, in a direction in which the second substrate faces the first substrate, on a side that is of the second substrate and that faces the liquid crystal layer, wherein the insulation medium glass layer has an inclined serration structure on a side facing the liquid crystal layer, and when the transparent electrode layer and the aluminized electrode layer are charged to form an electric field, the inclined serration structure functions as a second alignment and guiding layer and coordinates with the first alignment and guiding layer to control a deflection direction of liquid crystal molecules at the liquid crystal layer and the electric field also provides an electric field force to the liquid crystal molecules for rotation; wherein the insulation medium glass layer comprises pairs of oxide layers with different reflectivities and the pairs of oxide layers with different reflectivities are formed by sequential deposition of individual layers in a stacked manner over the electrode layer; wherein the pairs of oxide layers with different reflectivities comprise: a first oxide layer formed of a first oxide, and a second oxide layer formed of a second oxide that is different from the first oxide, the first oxide layer having a greater reflectivity as compared to a reflectivity of the second oxide layer, wherein a first pair of oxide layers of the pairs of oxide layers of the insulation medium glass layer is adjacent to the liquid crystal layer, and the inclined serration structure of the insulation medium glass layer is formed by the first oxide layer of the first pair of oxide layers, wherein the first oxide of the first oxide layer of the first pair of oxide layers is one of: ZrO.sub.2, and TiO.sub.2, and wherein the second oxide of the second oxide layer of the first pair of oxide layers is SiO.sub.2, and wherein the pairs of oxide layers with different reflectivities are specifically disposed in a manner of (0.5H 0.5L)*n, (0.5H L 0.5L)*n, or H (L H)*n, where H represents an optical thickness of a high-reflectivity material that is one-fourth of an operating wavelength, L represents an optical thickness of a low-reflectivity material that is one-fourth of the operating wavelength, and n represents a quantity of repetition times.

2. The spatial phase modulator according to claim 1, wherein an inclined angle of each inclined serration is between 3 and 15.

3. The spatial phase modulator according to claim 2, wherein the inclined angle of each inclined serration is between 3 and 10.

4. The spatial phase modulator according to claim 3, wherein the inclined angle of each inclined serration is one of: 3, 5, 7, and 10.

5. The spatial phase modulator according to claim 2, wherein the inclined angle of each inclined serration is one of: 12, 14, and 15.

6. The spatial phase modulator according to claim 1, wherein the first substrate is a glass substrate, and the second substrate is a silicon-based backplane.

7. The spatial phase modulator according to claim 1, wherein the second alignment and guiding layer is produced when an insulation medium glass layer is produced.

8. The spatial phase modulator according to claim 1, wherein the pairs of oxide layers are deposited by using one of a plasma method, a thermal evaporation method, or an electron beam method.

9. A method for producing a spatial phase modulator, the method comprising: forming a transparent electrode layer and a first alignment and guiding layer on a first substrate; forming an aluminized electrode layer and an insulation medium glass layer on a second substrate, and forming an inclined serration structure on a surface of the insulation medium glass layer, wherein the inclined serration structure functions as a second alignment and guiding layer and coordinates with the first alignment and guiding layer to control a deflection direction of liquid crystal molecules at a liquid crystal layer, wherein the aluminized electrode layer and the insulation medium glass layer are disposed in a cascading manner, in a direction in which the second substrate faces the first substrate, on a side that is of the second substrate and that faces the liquid crystal layer, wherein the insulation medium glass layer has an inclined serration structure on a side facing the liquid crystal layer, and when the transparent electrode layer and the aluminized electrode layer are charged to form an electric field, the inclined serration structure functions as a second alignment and guiding layer and coordinates with the first alignment and guiding layer to control a deflection direction of liquid crystal molecules at the liquid crystal layer and the electric field also provides an electric field force to the liquid crystal molecules for rotation; and meshing the first substrate and the second substrate and filling the liquid crystal layer between the first substrate and the second substrate, wherein when the first substrate and the second substrate are meshed, the first alignment and guiding layer and the inclined serration structure are oppositely disposed, wherein: the forming the aluminized electrode layer and the insulation medium glass layer on the second substrate, and forming the inclined serration structure on the surface of the insulation medium glass layer, comprise: forming the aluminized electrode layer on the second substrate; and forming pairs of oxide layers with different reflectivities at the formed aluminized electrode layer, wherein the pairs of oxide layers with different reflectivities are formed by sequential deposition of individual layers in a stacked manner over the aluminized electrode layer, wherein the pairs of oxide layers with different reflectivities comprise: a first oxide layer formed of a first oxide, and a second oxide layer formed of a second oxide that is different from the first oxide, the first oxide layer having a greater reflectivity as compared to a reflectivity of the second oxide layer, wherein when a last oxide layer is being formed, the second substrate is rotated by a specified angle, to form the last oxide layer of the inclined serration structure, and an inclined direction of each inclined serration faces an alignment direction of the liquid crystal layer, wherein a first pair of oxide layers of the pairs of oxide layers of the insulation medium glass layer is adjacent to the liquid crystal layer, and the inclined serration structure of the insulation medium glass layer is formed by the first oxide layer of the first pair of oxide layers, and wherein the first oxide of the first oxide layer of the first pair of oxide layers is one of: ZrO.sub.2, and TiO.sub.2, and wherein the second oxide of the second oxide layer of the first pair of oxide layers is SiO.sub.2, and wherein the pairs of oxide layers with different reflectivities are specifically disposed in a manner of (0.5H 0.5L)*n, (0.5H L 0.5L)*n, or H (L H)*n, where H represents an optical thickness of a high-reflectivity material that is one-fourth of an operating wavelength, L represents an optical thickness of a low-reflectivity material that is one-fourth of the operating wavelength, and n represents a quantity of repetition times.

10. The method according to claim 9, wherein when the last oxide layer of the inclined serration structure is formed, an inclined angle of each formed inclined serration is between 3 and 15.

11. The method according to claim 10, further comprising: before oxide layers with different reflectivities are alternately formed at the formed electrode layer, determining: a material, a thickness of the material, and the inclined serration width, of each oxide layer according to an operating wavelength of the spatial phase modulator.

12. The method according to claim 9, wherein the last oxide layer is formed at a thickness of between 90 nm and 350 nm.

13. The method according to claim 9, wherein the second alignment and guiding layer is produced when the insulation medium glass layer is produced.

14. The method according to claim 9, wherein the pairs of oxide layers are deposited by using one of a plasma method, a thermal evaporation method, or an electron beam method.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a schematic structural diagram of a spatial phase modulator in the conventional art;

(2) FIG. 2 is a schematic structural diagram of a silicon-based backplane of a spatial phase modulator in the conventional art;

(3) FIG. 3 is a schematic structural diagram of a spatial phase modulator according to an embodiment of the present invention;

(4) FIG. 4a and FIG. 4b are flowcharts of producing an insulation medium glass layer according to an embodiment of the present invention;

(5) FIG. 5 is a schematic structural diagram of a spatial phase modulator according to an embodiment of the present invention;

(6) FIG. 6 is a reflectivity emulation diagram of the spatial phase modulator shown in FIG. 5; and

(7) FIG. 7 is a response time experiment diagram of the spatial phase modulator shown in FIG. 5.

(8) TABLE-US-00001 Reference numerals: 1: Surface glass layer 2: Common ITO 3: Upper alignment electrode layer and guiding layer 4: Liquid crystal 5: Lower alignment and 6: Electrode layer molecule layer guiding layer 7: Silicon-based 8: Insulation glass layer 10: Second substrate backplane 20: Electrode layer 30: Insulation medium 31: First oxide layer glass layer 32: Second oxide layer 321: Inclined serration 40: Liquid crystal structure layer 50: First alignment and 60: Transparent electrode 70: First substrate guiding layer layer 80: Deposition source

DESCRIPTION OF EMBODIMENTS

(9) The following describes the specific embodiments of the present invention in detail with reference to accompanying drawings. It should be understood that the specific implementations described herein are merely used to explain the present invention but are not intended to limit the present invention.

(10) As shown in FIG. 3, FIG. 3 is a schematic structural diagram of a spatial phase modulator according to an embodiment of the present invention.

(11) This embodiment of the present invention provides the spatial phase modulator. The spatial phase modulator includes a first substrate 70 and a second substrate 10 that are meshed together, and a liquid crystal layer 40 disposed between the first substrate 70 and the second substrate 10, where a transparent electrode layer 60 and a first alignment and guiding layer 50 are disposed, in a cascading manner in a direction in which the first substrate 70 faces the second substrate 10, on a side that is of the first substrate 70 and that faces the liquid crystal layer 40; and an electrode layer 20 and an insulation medium glass layer 30 are disposed, in a cascading manner in a direction in which the second substrate 10 faces the first substrate 70, on a side that is of the second substrate 10 and that faces the liquid crystal layer 40, where the insulation medium glass layer 30 has an inclined serration structure 321 on a side facing the liquid crystal layer 40, and when the transparent electrode layer 60 and the electrode layer 20 are charged to form an electric field, the inclined serration structure 321 functions as a second alignment and guiding layer and coordinates with the first alignment and guiding layer 50 to control a deflection direction of liquid crystal molecules at the liquid crystal layer 40.

(12) In the foregoing embodiment, an inclined serration structure 321 is formed at an insulation medium glass layer 30 and functions as a second alignment and guiding layer. In this way, the second alignment and guiding layer can be produced when the insulation medium glass layer 30 is produced. This simplifies steps for producing the spatial phase modulator. In addition, in comparison with the conventional art, in a process of producing the spatial phase modulator provided in this embodiment, the inclined serration structure 321 is formed when the insulation medium glass layer 30 is formed. This avoids prior-art damages to the insulation medium glass layer 30 that are caused when an alignment and guiding layer is formed at the insulation medium glass layer 30 by means of mechanical friction during production of a spatial phase modulator. Therefore, a yield of spatial phase modulators is increased, and in addition, a difficulty in producing a spatial phase modulator is reduced, and a production technology is simplified.

(13) In addition, when the inclined serration structure 321 at the insulation medium glass layer 30 is specifically produced, an inclined angle of a serration may be flexibly changed without being affected by a device, thereby effectively increasing a switching speed of the spatial phase modulator. Specifically, as shown in FIG. 4a and FIG. 4b, FIG. 4a and FIG. 4b show technological steps for forming the insulation medium glass layer 30. The insulation medium glass layer 30 includes multiple oxide layers with different reflectivities. Specifically, the insulation medium glass layer 30 includes at least one pair of oxide layers with different reflectivities. For example, one pair of oxide layers with different reflectivities shown in FIG. 3 are respectively a first oxide layer 31 and a second oxide layer 32. When the insulation medium glass layer 30 is formed, first oxide layers 31 and second oxide layers 32 are alternately disposed. Oxide at the oxide layers is ZrO.sub.2, SiO.sub.2, TiO.sub.2, or other oxide. During specific production, a proper oxide layer, thickness, quantity of cycles, and an inclined serration width x are first selected according to an operating wavelength and a characteristic (such as reflectivity) requirement of the spatial phase modulator, to first form the layers of oxide at the insulation medium glass layer 30. Then, the layers of oxide are deposited on a backplane in the spatial phase modulator by means of evaporation. The deposition manner may be a plasma method (plasma), a thermal evaporation method (thermal), an electron beam method (Electron), or the like. When the inclined serration structure 321 is formed, the inclined serration structure 321 is disposed at an oxide layer adjacent to the liquid crystal layer 40. Specifically, the second substrate 10 is rotated by an angle on a rotating platform (or a deposition source 80 is rotated by an angle relative to the second substrate 10), so that there is an included angle between the spatial phase modulator and the deposition source 80. The included angle is consistent with the inclined angle of the serration. The inclined angle is between 3 and 15, for example, different inclined angles such as 3, 5, 7, 10, 12, 14, or 15. An uppermost layer of material of the insulation medium glass layer 30 is deposited in an evaporation manner, such as a plasma, thermal, or electron source method, to form the inclined serration structure, as shown in FIG. 3. The inclined angle is an angle a, and the angle is between 3 and 10, for example, different inclined angles such as 3, 5, 7, or 10. It can be learned from the foregoing descriptions that the inclined angle of the inclined serration structure 321 at the insulation medium glass layer 30 in the spatial phase modulator provided in this embodiment may be adjusted as required, without being affected by a structure of a device. This facilitates adjustment to the inclined angle of the inclined serration according to an actual case.

(14) In a specific embodiment of the present invention, a glass substrate is used as the first substrate 70, and a silicon-based backplane is used as the second substrate 10. In addition, the electrode layer 20 in the spatial phase modulator is an aluminized electrode layer. The aluminized electrode layer and the transparent electrode layer 60 form an electric field, to provide electric field force to liquid crystal molecules for rotation.

(15) For ease of understanding of the embodiments of the present invention, the following describes a specific embodiment of the present invention with reference to FIG. 5.

(16) A first substrate 70, a transparent electrode layer 60, and a first alignment and guiding layer 50 in a spatial phase modulator provided in this embodiment are the same as those in the spatial phase modulator provided in the foregoing embodiment, and therefore, are not illustrated in FIG. 5. FIG. 5 shows only a specific structure of an insulation medium glass layer 30. ZrO.sub.2 and SiO.sub.2 are used as oxide at the insulation medium glass layer 30. A quantity of layers and thicknesses of the layers at the insulation medium glass layer 30 are shown in FIG. 5. The thicknesses are obtained by means of optimization according to an operating wavelength and a characteristic (such as reflectivity) requirement of the spatial phase modulator.

(17) A band applied to the spatial phase modulator described in this embodiment is a 1550 nm band. First, it is assumed that an inclined angle of an inclined serration structure 321 is 5, and that ZrO.sub.2 and SiO.sub.2 are selected as oxide materials of the insulation medium glass layer 30. The ZrO.sub.2 is used as a high-reflectivity material, and the SiO.sub.2 is used as a low-reflectivity material. The insulation medium glass layer 30 is designed in a (0.5H L 0.5H).sup.{circumflex over ()}n structure. Finally, an optimized structure of the insulation medium glass layer 30 is shown in FIG. 5. A serration width is 3 mm. Therefore, a thickness of an uppermost layer of ZrO.sub.2 material varies between 90 nm and 350 nm. This layer is used as both an uppermost layer of the insulation medium glass layer 30 and a second alignment and guiding layer, and can implement deflecting and guiding of liquid crystal molecules.

(18) The structure of the insulation medium glass layer 30 is emulated. It can be learned from the results (as shown in FIG. 6) that although the uppermost layer of the insulation medium glass layer 30 is a tilted layer, thicknesses, corresponding to different positions, of the structure of the insulation medium glass layer 30 are different. However, this has little impact on a reflectivity of a component. The reflectivity of the entire component is greater than 96%, and a reflectivity difference caused by different thicknesses is less than 2%.

(19) The entire component is packaged according to design of the insulation medium glass layer 30 and the aforementioned technological steps. FIG. 7 is experimental test results of reflectivities of the component. It can be learned from FIG. 7 that after the insulation medium glass layer 30 is added to the spatial phase modulator, a reflectivity of the component is increased from 75% to over 95%, and dependence on wavelengths, from 1520 nm to 1570 nm, is also reduced. After the insulation medium glass layer 30 is introduced, wavelength dependence is less than 1%.

(20) Referring to FIG. 3, FIG. 4a, and FIG. 4b, an embodiment of the present invention further provides a method for producing a spatial phase modulator. The production method includes the following steps:

(21) forming a transparent electrode layer 60 and a first alignment and guiding layer 50 on a first substrate 70;

(22) forming an electrode layer 20 and an insulation medium glass layer 30 on a second substrate 10, and forming an inclined serration structure 321 on a surface of the insulation medium glass layer 30, where the inclined serration structure 321 functions as a second alignment and guiding layer and coordinates with the first alignment and guiding layer 50 to control a deflection direction of liquid crystal molecules at the liquid crystal layer 40; and

(23) meshing the first substrate 70 and the second substrate 10 and filling the liquid crystal layer 40, where when the first substrate 70 and the second substrate 10 are meshed, the first alignment and guiding layer 50 and the inclined serration structure 321 are oppositely disposed.

(24) In the foregoing embodiment, an inclined serration structure 321 is formed when an insulation medium glass layer 30 is formed. This avoids prior-art damages to the insulation medium glass layer 30 that are caused when an alignment and guiding layer is formed at the insulation medium glass layer 30 by means of mechanical friction during production of a spatial phase modulator. Therefore, a yield of spatial phase modulators is increased, and in addition, a difficulty in producing a spatial phase modulator is reduced, and a production technology is simplified. In addition, an inclined angle of the inclined serration structure 321 may be flexibly changed. That is, the inclined angle of the inclined serration structure 321 may be determined according to a degree of inclination after the insulation medium glass layer is adjusted, without being affected by a device, thereby effectively increasing a switching speed of the spatial phase modulator.

(25) For ease of understanding of the production method provided in this embodiment, the following provides descriptions with reference to detailed production steps.

(26) Step 1: Form a transparent electrode layer 60 and a first alignment and guiding layer 50 on a first substrate 70.

(27) Specifically, a glass substrate is used as the first substrate 70. The transparent electrode layer 60 is formed on the glass substrate by means of etching and exposure or the like. A layer of oxide is deposited on the formed transparent electrode layer 60, and the first alignment and guiding layer 50 is formed by means of mechanical friction.

(28) Step 2: Form an electrode layer 20 and an insulation medium glass layer 30 on a second substrate 10, and form an inclined serration structure 321 on a surface of the insulation medium glass layer 30, where the inclined serration structure 321 functions as a second alignment and guiding layer and coordinates with the first alignment and guiding layer 50 to control a deflection direction of liquid crystal molecules at the liquid crystal layer 40.

(29) Specifically, the electrode layer 20 is first formed on the first substrate 70. Then, at least one pair of oxide layers with different reflectivities are formed at the formed electrode layer 20. When the last oxide layer is being formed, the first substrate 70 is rotated by a specified angle, to form the last oxide layer of the inclined serration structure 321. An inclined direction of the inclined serration faces an alignment direction of the liquid crystal layer 40.

(30) Before oxide layers with different reflectivities are alternately formed at the formed electrode layer 20, material, thickness, quantity of cycles, and inclined serration width of each oxide layer are optimized according to an operating wavelength and a characteristic requirement of a spatial phase modulator. When the at least one pair of oxide layers with different reflectivities are specifically disposed, a manner of (0.5H 0.5L).sup.{circumflex over ()}n, (0.5H L 0.5H).sup.{circumflex over ()}n, or H (L H).sup.{circumflex over ()}n may be used for production. In this embodiment, a band C (1530-1570 nm) is used as an example. H represents an optical thickness that is one-fourth of a wavelength in the band C (where the wavelength is generally a center wavelength 1550 nm) (high-reflectivity material); L represents an optical thickness that is one-fourth of 1550 nm (low-reflectivity material); and n represents a quantity of repetition times. For example, if a high-reflectivity material is A, a reflectivity of the material A is r1, a low-reflectivity material is B, a reflectivity of the material B is r2, and a value of n is 3, materials of (0.5H 0.5L).sup.{circumflex over ()}n are sequentially ABABAB, a thickness of the material A is (0.51550 nm)/(4r1), and a thickness of B is (0.51550 nm)/(4r2); materials of (0.5H L 0.5H).sup.{circumflex over ()}n are sequentially ABA ABA ABA, a thickness of the material A is (0.51550 nm)/(4r1), and a thickness of B is (11550 nm)/(4r2); and materials of H (L H).sup.{circumflex over ()}n are sequentially A BA BA BA, a thickness of the material A is (11550 nm)/(4r1), and a thickness of B is (11550 nm)/(4r2).

(31) As shown in FIG. 4a, the oxide layers are deposited on a backplane in the spatial phase modulator by means of evaporation. The deposition manner may be a plasma method (plasma), a thermal evaporation method (thermal), an electron beam method (Electron), or the like. A thickness of each layer is implemented, according to an optimized value determined when the insulation medium glass layer 30 is designed, by controlling parameters such as a deposition temperature and time. The process is repeated multiple times to implement deposition of layers (excluding an uppermost oxide layer, with an inclined angle, at the insulation medium glass layer 30) at the insulation medium glass layer 30. After the oxide layer is completed, as shown in FIG. 4b, a silicon-based backplane is rotated by an angle on a rotating platform (or a deposition source 80 is rotated by an angle relative to the silicon-based backplane), so that there is an included angle between the spatial phase modulator and the deposition source 80. The included angle is consistent with an inclined angle of a serration. The inclined angle is between 3 and 10, for example, different inclined angles such as 3, 5, 7, or 10. An uppermost layer of material of the insulation medium glass layer 30 is deposited in an evaporation manner, such as a plasma, thermal, or electron source method.

(32) Step 3: Mesh the first substrate 70 and the second substrate 10 and fill the liquid crystal layer 40, where when the first substrate 70 and the second substrate 10 are meshed, the first alignment and guiding layer 50 and the inclined serration structure 321 are oppositely disposed.

(33) Specifically, the first substrate 70 and the second substrate 10 are meshed, and the first alignment and guiding layer 50 and the inclined serration structure 321 are oppositely disposed. Liquid crystal is filled between the first substrate 70 and the second substrate 10, to complete production of the entire spatial phase modulator.

(34) It can be learned from descriptions in the foregoing specific embodiments, in this embodiment, during production of a spatial phase modulator, when an oxide layer is formed, an inclined serration structure 321 that coordinates with a first alignment and guiding layer 50 is formed using a same technology, thereby facilitating production of the spatial phase modulator. In addition, this avoids damages to oxide that are caused when a second alignment and guiding layer is formed at the oxide layer by using a friction technology. Therefore, a yield of spatial phase modulators is increased.

(35) Obviously, a person skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. The present invention is intended to cover these modifications and variations provided that they fall within the scope of protection defined by the following claims and their equivalent technologies.