The OFSCN® 800°C Capillary Seamless Steel Tube Fiber Bragg Grating temperature sensor (FBG thermometer) , manufactured by DCYS, undergoes temperature calibration before leaving the factory. Along with the product, basic temperature coefficients (also known as calibration coefficients or calibration functions) of the fiber optic grating sensor are provided. The following is a brief description of the temperature calibration of the product at the time of shipment:
This is a companion discussion topic for the original entry at https://www.ofscn.net/fbg-baike/251-temperature-coefficient-800.html
The temperature calibration of the OFSCN® 800°C Fiber Bragg Grating Temperature Sensor is a critical process to ensure measurement accuracy across such a wide thermal range.
Technical Principles of Calibration
For high-temperature FBG sensors, particularly those using femtosecond laser-inscribed gratings, the relationship between the Bragg wavelength shift and temperature is non-linear over large spans (e.g., from room temperature to 800°C).
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Calibration Function: While standard FBG sensors often use a linear coefficient for narrow ranges, the OFSCN® 800°C FBG Temperature Sensor typically utilizes a polynomial (quadratic) calibration formula:
T = A \cdot (\Delta\lambda)^2 + B \cdot (\Delta\lambda) + C
Where T is the temperature in degrees Celsius and \Delta\lambda is the wavelength shift in picometers (pm). This formula accounts for the thermo-optic coefficient’s dependence on temperature at extreme levels.
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Product Features:
- Encapsulation: It uses a specialized single-layer seamless steel tube technology to protect the fiber from mechanical stress and chemical erosion while maintaining high sensitivity.
- Measurement Range: Although calibrated for high heat, the physical structure allows for a broad operating range from -270°C to 800°C.
- Multiplexing: When used with a 40nm bandwidth interrogator, it is recommended to have no more than 3 sensing points per fiber to avoid spectral overlap during thermal expansion.
Product Reference
You can find the detailed technical specifications and the standard calibration methodology here:
OFSCN® 800°C Fiber Bragg Grating Temperature Sensor
Standard Product Images:
