MOF-SPR sensor with D-type surface coated with indium tin oxide film

Abstract

The invention belongs to the technical field of optical sensors, and particularly relates to a low-consumption and high-sensitivity D-type MOF-SPR sensor with the surface coated with an indium tin oxide film, inner-layer elliptical holes, outer-layer large air holes and outer-layer small air holes are formed in a cladding of an optical fiber, the number of the inner-layer elliptical holes is two, the inner-layer elliptical holes are symmetrically distributed about a fiber core on the X axis, the air holes are all distributed in a regular hexagon shape, and the outer-layer large air holes and the outer-layer small air holes are formed in the cladding of the optical fiber. The outer-layer large air holes and the outer-layer small air holes are arranged in a staggered manner; a polishing and grinding surface parallel to the X axis is polished and ground in the positive direction of the Y axis, and the polishing and grinding surface is coated with an indium tin oxide film; the number of large air holes in the inner layer and the outer layer of the polished cladding is five, and the number of small air holes in the outer layer is four; the distance from the circle center of the outer-layer small air hole to the fiber core is larger than the distance from the circle center of the outer-layer large air hole to the fiber core, and the distance from the circle center of the outer-layer large air hole to the fiber core is larger than the distance from the center of the inner-layer elliptical hole to the fiber core. The sensor is simple in processing technology, low in loss, high in sensitivity and capable of resisting severe environments.

Description

Technical Field

[0001] This invention belongs to the field of optical sensor technology, specifically relating to a low-power, high-sensitivity MOF-SPR sensor with a D-type surface coated with an indium tin oxide film. Background Technology

[0002] Surface plasmon resonance (SPR) technology is a representative emerging optical sensing technology in recent years. Microstructure optical fiber (MOF) is a waveguide formed by introducing a series of air holes. Existing MOF-SPR sensors mostly involve coating within the holes. The small size of the fiber limits the maneuverability of the coating, making the fabrication process complex and difficult to apply in practice. In addition, the hole array arrangement of existing fiber sensors is complex, and most of them are circular air holes, which limits their measurement range and has low sensitivity. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a MOF-SPR sensor with a D-type surface coated with an indium tin oxide film. This sensor has a simple manufacturing process, low loss, high sensitivity, and can withstand harsh environments.

[0004] The technical solution adopted in this invention is as follows: a D-type MOF-SPR sensor with an indium tin oxide film coated on its surface. The MOF-SPR sensor is a photonic crystal fiber. The cladding of the fiber has an inner elliptical hole, an outer large air hole, and an outer small air hole. There are two inner elliptical holes, which are symmetrically distributed about the fiber core along the X-axis. The outer large and small air holes are both hexagonal in shape and are arranged alternately. The positive Y-axis has a polishing surface parallel to the X-axis, and the polishing surface is coated with an indium tin oxide film. After polishing, there are five outer large air holes and four outer small air holes in the cladding. The distance from the center of the outer small air hole to the fiber core is greater than the distance from the center of the outer large air hole to the fiber core, and the distance from the center of the outer large air hole to the fiber core is greater than the distance from the center of the inner elliptical hole to the fiber core.

[0005] The cladding has a radius of 16-20 micrometers, the major axis radius of the inner elliptical holes is 2-4 micrometers, the minor axis radius is 1-3 micrometers, the radius of the outer large air holes is 2-4 micrometers, the radius of the outer small air holes is 1-2 micrometers, and the thickness of the indium tin oxide film is 15-35 nanometers.

[0006] Furthermore, the cladding has a radius of 18 micrometers, the major axis radius of the inner elliptical hole is 3 micrometers, its minor axis radius is 1.5 micrometers, the radius of the outer large air hole is 3 micrometers, the radius of the outer small air hole is 1.5 micrometers, and the thickness of the indium tin oxide film is 25 nanometers.

[0007] Furthermore, the cladding has a radius of 16 micrometers, the major axis radius of the inner elliptical hole is 2 micrometers, its minor axis radius is 1 micrometer, the radius of the outer large air hole is 2 micrometers, the radius of the outer small air hole is 1 micrometer, and the thickness of the indium tin oxide film is 15 nanometers.

[0008] Furthermore, the cladding has a radius of 20 micrometers, the major axis radius of the inner elliptical hole is 4 micrometers, its minor axis radius is 3 micrometers, the radius of the outer large air hole is 4 micrometers, the radius of the outer small air hole is 2 micrometers, and the thickness of the indium tin oxide film is 35 nanometers.

[0009] Furthermore, the outer layer of the photonic crystal fiber is provided with a perfect matching layer for absorbing scattered light and preventing scattering.

[0010] Furthermore, the material of the photonic crystal fiber is silicon dioxide.

[0011] The beneficial effects of this invention are as follows: This invention provides a D-type MOF-SPR sensor with an indium tin oxide film coated on its surface. This sensor has a simple fabrication process, low loss, high sensitivity, and can withstand harsh environments. The maximum and average sensitivities are 80,000 nm / RIU and 20,000 nm / RIU, respectively; the loss limit is below 56 dB / cm, which is beneficial for long-distance transmission. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the cross-section of the MOF-SPR sensor. Detailed Implementation

[0013] Reference Figure 1 A D-type MOF-SPR sensor with an indium tin oxide film coated on its surface is disclosed. The MOF-SPR sensor is a photonic crystal fiber 1. The cladding of the fiber has an inner elliptical hole 4, an outer large air hole 3, and an outer small air hole 2. There are two inner elliptical holes, which are symmetrically distributed about the fiber core along the X-axis. The outer large and small air holes are both hexagonal and are arranged alternately. A polishing surface 5 parallel to the X-axis is polished in the positive Y-axis direction, and an indium tin oxide film 6 is coated on the polishing surface. After polishing, there are five outer large air holes and four outer small air holes in the cladding. The distance from the center of the outer small air hole to the fiber core is greater than the distance from the center of the outer large air hole to the fiber core, and the distance from the center of the outer large air hole to the fiber core is greater than the distance from the center of the inner elliptical hole to the fiber core.

[0014] The cladding has a radius of 18 micrometers, the major axis radius of the inner elliptical hole is 3 micrometers, its minor axis radius is 1.5 micrometers, the radius of the outer large air hole is 3 micrometers, the radius of the outer small air hole is 1.5 micrometers, and the thickness of the indium tin oxide film is 25 nanometers. Example

[0015] The MOF-SPR sensor with a D-type surface coated with an indium tin oxide film has a cladding radius of 16 micrometers, an inner elliptical hole with a major axis radius of 2 micrometers and a minor axis radius of 1 micrometer, an outer large air hole with a radius of 2 micrometers, an outer small air hole with a radius of 1 micrometer, and an indium tin oxide film thickness of 15 nanometers. Example

[0016] The MOF-SPR sensor with a D-type surface coated with an indium tin oxide film has a cladding radius of 20 micrometers, an inner elliptical aperture with a major axis radius of 4 micrometers and a minor axis radius of 3 micrometers, an outer large air aperture with a radius of 4 micrometers, an outer small air aperture with a radius of 2 micrometers, and an indium tin oxide film thickness of 35 nanometers.

[0017] The sensor has a maximum and average sensitivity of 80,000 nm / RIU and 20,000 nm / RIU, respectively, within an ultra-wide refractive index (1.00-1.38) detection range. It does not require a special light source in the low-band and can solve special applications in the high-band. The limiting loss is below 56 dB / cm, which is conducive to long-distance transmission. The manufacturing process is simple and easy to produce and apply in practice. It can be widely used in different scenarios in basic sciences and practical engineering fields.

Claims

1. A MOF-SPR sensor with a D-type surface coated with an indium tin oxide film, characterized in that: The MOF-SPR sensor is a photonic crystal fiber. The fiber cladding contains inner elliptical holes, outer large air holes, and outer small air holes. There are two inner elliptical holes, symmetrically distributed about the fiber core along the X-axis. The outer large and small air holes are both hexagonal in shape and are arranged alternately. The positive Y-axis direction has a polishing surface parallel to the X-axis, coated with an indium tin oxide film. After polishing, the cladding contains five outer large air holes and four outer small air holes. The distance from the center of the outer small air hole to the fiber core is greater than the distance from the center of the outer large air hole to the fiber core, and the distance from the center of the outer large air hole to the fiber core is greater than the distance from the center of the inner elliptical hole to the fiber core. The radius of the cladding layer is 16-20 micrometers, the major axis radius of the inner elliptical hole is 2-4 micrometers, the minor axis radius is 1-3 micrometers, the radius of the outer large air hole is 2-4 micrometers, the radius of the outer small air hole is 1-2 micrometers, and the thickness of the indium tin oxide film is 15-35 nanometers.

2. The MOF-SPR sensor with D-type surface coated with indium tin oxide film according to claim 1, characterized in that: The cladding has a radius of 18 micrometers, the major axis radius of the inner elliptical hole is 3 micrometers, the minor axis radius is 1.5 micrometers, the radius of the outer large air hole is 3 micrometers, the radius of the outer small air hole is 1.5 micrometers, and the thickness of the indium tin oxide film is 25 nanometers.

3. The MOF-SPR sensor with D-type surface coated with indium tin oxide film according to claim 1, characterized in that: The cladding has a radius of 16 micrometers, the major axis radius of the inner elliptical hole is 2 micrometers, the minor axis radius is 1 micrometer, the radius of the outer large air hole is 2 micrometers, the radius of the outer small air hole is 1 micrometer, and the thickness of the indium tin oxide film is 15 nanometers.

4. The MOF-SPR sensor with D-type surface coated with indium tin oxide film according to claim 1, characterized in that: The cladding has a radius of 20 micrometers, the major axis radius of the inner elliptical hole is 4 micrometers, the minor axis radius is 3 micrometers, the radius of the outer large air hole is 4 micrometers, the radius of the outer small air hole is 2 micrometers, and the thickness of the indium tin oxide film is 35 nanometers.

5. The MOF-SPR sensor with D-type surface coated with indium tin oxide film according to any one of claims 1-4, characterized in that: The outer layer of the photonic crystal fiber is provided with a perfect matching layer for absorbing scattered light and preventing scattering.

6. The MOF-SPR sensor with D-type surface coated with indium tin oxide film according to any one of claims 1-4, characterized in that: The photonic crystal fiber is made of silicon dioxide.

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