Fiber optic sensor and methods and apparatus relating thereto

A fiber optic surface plasmon resonance system, comprising:

• a) an in-line transmission-based fiber optic surface plasmon resonance sensor wherein the sensor comprises an optical fiber having a core and a cladding or cladding/buffer layer surrounding the core, and having an input end and an output end, wherein the optical fiber has a sensing area located between the input end and output end, and wherein the sensing area is defined by a layer of surface plasmon resonance supporting metal in contact with at least a portion of the optical fiber core free from the surrounding cladding or cladding/buffer layer;
• b) a source of electromagnetic radiation of multiple wavelengths whose output is applied to the input end of the optical fiber such that the radiation propagates from the input end towards the output end by total internal reflections;
• and
• c) a detector which receives the radiation exiting the output end of the optical fiber.

A fiber optic surface plasmon resonance system, comprising:

• a) a terminated reflection-based fiber optic surface plasmon resonance sensor wherein the sensor comprises an optical fiber having a core and a cladding or cladding/buffer layer surrounding the core, and having an input/output end and a terminal reflection end, wherein the terminal reflection end is defined by an end face of the core in contact with a reflective layer that does not support surface plasmon resonance, wherein the optical fiber has a sensing area located between the input/output end and the terminal reflection end or at the terminal reflection end, and wherein the sensing area is defined by a layer of surface plasmon resonance supporting metal in contact with at least a portion of the optical fiber core free from the surrounding cladding or cladding/buffer layer;
• b) a source of electromagnetic radiation of multiple wavelengths whose output is applied to the input/output end of the optical fiber, and wherein the radiation propagates from the input/output end towards the terminal reflection end by total internal reflections, internally reflects off the reflective layer in contact with the end face of the core, and propagates back down the optical fiber by total internal reflections towards the input/output end;
• and
• c) a detector which receives the radiation exiting the input/output end of the optical fiber.

A method for evaluating a sample comprising:

• a) contacting the sample with an in-line transmission-based optical fiber sensor wherein the sensor comprises an optical fiber having a core and a cladding or cladding/buffer layer surrounding the core, and having an input end and an output end, wherein the optical fiber has a sensing area located between the input end and output end, and wherein the sensing area is defined by a layer of surface plasmon resonance supporting metal in contact with at least a portion of the optical fiber core free from the surrounding cladding or cladding/buffer layer, and wherein the sensing area of the sensor is in contact with the sample;
• b) directing a source of electromagnetic radiation of multiple wavelengths into the input end of the optical fiber core such that the radiation propagates from the input end towards the output end of the optical fiber core by total internal reflections, and wherein the propagating radiation interacts with the sensing area of the sensor which is in contact with the sample;
• and
• c) measuring the radiation exiting the output end of the optical fiber.

A method for evaluating a sample, comprising:

• a) contacting the sample with a terminated reflection-based optical fiber surface plasmon resonance sensor wherein the sensor comprises an optical fiber having a core and a cladding or cladding/buffer layer surrounding the core, and having an input/output end and a terminal reflection end, wherein the terminal reflection end is defined by an end face of the core in contact with a reflective layer that does not support surface plasmon resonance, wherein the optical fiber has a sensing area located between the input/output end and terminal reflection end or at the terminal reflection end, and wherein the sensing area is defined by a layer of surface plasmon resonance supporting metal in contact with at least a portion of the optical fiber core free from the surrounding cladding or cladding/buffer layer, and wherein the sensing area of the sensor is in contact with the sample;
• b) directing a source of electromagnetic radiation of multiple wavelengths into the input/output end of the optical fiber core such that the radiation propagates from the input/output end towards the terminal reflection end by total internal reflections, internally reflects off the reflective layer in contact with the end face of the core, and propagates back down the optical fiber core by total internal reflections towards the input/output end, and wherein the propagating radiation interacts with the sensing area of the sensor which is in contact with the sample;
• and
• c) measuring the radiation exiting the input/output end of the optical fiber.

A fiber optic surface plasmon resonance system, comprising:

• a) an in-line transmission-based fiber optic surface plasmon resonance sensor wherein the sensor comprises an optical fiber having a core and a cladding or cladding/buffer layer surrounding the core, and having an input end and an output end, wherein the optical fiber has a sensing area located between the input end and output end, and wherein the sensing area is defined by a layer of surface plasmon resonance supporting metal in contact with at least a portion of the optical fiber core free from the surrounding cladding or cladding/buffer layer;
• b) a source of electromagnetic radiation of multiple wavelengths whose output is applied to the input end of the optical fiber such that the radiation propagates from the input end towards the output end by total internal reflections;
• and
• c) a spectral intensity distribution detector which receives the radiation exiting the output end of the optical fiber.

A fiber optic surface plasmon resonance system, comprising:

• a) an in-line transmission-based fiber optic surface plasmon resonance sensor wherein the sensor comprises an optical fiber having a core and a cladding or cladding/buffer layer surrounding the core, and having an input end and an output end, wherein the optical fiber has a sensing area located between the input end and output end, and wherein the sensing area is defined by a layer of surface plasmon resonance supporting metal in contact with at least a portion of the optical fiber core free from the surrounding cladding or cladding/buffer layer;
• b) a source of electromagnetic radiation of multiple wavelengths whose output is applied to the input end of the optical fiber such that the radiation propagates from the input end towards the output end by total internal reflections;
• and
• c) an analyzer which receives the radiation exiting the output end of the optical fiber.

A fiber optic surface plasmon resonance system, comprising:

• a) a terminated reflection-based fiber optic surface plasmon resonance sensor wherein the sensor comprises an optical fiber having a core and a cladding or cladding/buffer layer surrounding the core, and having an input/output end and a terminal reflection end, wherein the terminal reflection end is defined by an end face of the core in contact with a reflective layer that does not support surface plasmon resonance, wherein the optical fiber has a sensing area located between the input/output end and the terminal reflection end or at the terminal reflection end, and wherein the sensing area is defined by a layer of surface plasmon resonance supporting metal in contact with at least a portion of the optical fiber core free from the surrounding cladding or cladding/buffer layer;
• b) a source of electromagnetic radiation of multiple wavelengths whose output is applied to the input/output end of the optical fiber, and wherein the radiation propagates from the input/output end towards the terminal reflection end by total internal reflections, internally reflects off the reflective layer in contact with the end face of the core, and propagates back down the optical fiber by total internal reflections towards the input/output end;
• and
• c) a spectral intensity distribution detector which receives the radiation exiting the input/output end of the optical fiber.

A fiber optic surface plasmon resonance system, comprising:

• a) a terminated reflection-based fiber optic surface plasmon resonance sensor wherein the sensor comprises an optical fiber having a core and a cladding or cladding/buffer layer surrounding the core, and having an input/output end and a terminal reflection end, wherein the terminal reflection end is defined by an end face of the core in contact with a reflective layer that does not support surface plasmon resonance, wherein the optical fiber has a sensing area located between the input/output end and the terminal reflection end or at the terminal reflection end, and wherein the sensing area is defined by a layer of surface plasmon resonance supporting metal in contact with at least a portion of the optical fiber core free from the surrounding cladding or cladding/buffer layer;
• b) a source of electromagnetic radiation of multiple wavelengths whose output is applied to the input/output end of the optical fiber, and wherein the radiation propagates from the input/output end towards the terminal reflection end by total internal reflections, internally reflects off the reflective layer in contact with the end face of the core, and propagates back down the optical fiber by total internal reflections towards the input/output end;
• and
• c) an analyzer which receives the radiation exiting the input/output end of the optical fiber.