Fiber numerical aperture is a parameter that determines the angle range at which a fiber can receive light radiation, and it is also an important parameter for the coupling efficiency between the fiber and the light source, photodetector, and other fibers; At the same time, it has an impact on connection loss, micro bending loss, attenuation temperature characteristics, transmission bandwidth, etc.
Fiber optic numerical aperture testing experimental instrumentIt is an experimental instrument developed by our company for fiber optic numerical aperture measurement. This instrument allows students to build their own system, master the method of adjusting the optical path, and intuitively understand the principle of fiber optic numerical aperture measurement. At the same time, they can also conduct fiber optic sensing principle experiments through the existing platform of the instrument, which exercises students' hands-on and brainpower abilities.
Precautions for Fiber Numerical Aperture (NA) Testing:
Test environment control:
Light source stability: High stability laser light sources (such as 1310nm/1550nm) should be used to avoid power fluctuations affecting the measurement accuracy of far-field light intensity distribution.
Environmental light interference: The testing area should be shaded to prevent stray light from interfering with the readings of the power meter. It is recommended to use protective barriers
Sample preparation and calibration:
End face treatment: The fiber end face needs to be clean and free of scratches, broken edges, or contamination (such as dust, oil stains), otherwise it will cause an increase in reflection loss or NA value deviation.
Fiber optic fixation: It is necessary to straighten the fiber optic cable and avoid bending. If the bending radius is too small, it may introduce additional attenuation and affect the NA test results
Data collection and analysis:
Dynamic range: The power meter needs to have sufficient dynamic range to accurately capture low-intensity edge light signals.
Multiple measurements: It is recommended to repeat the test at least 3 times and take the average to reduce random errors.
Equipment maintenance and verification:
Regular calibration: The tester needs to be calibrated regularly using standard optical fibers (such as calibration fibers with NA=0.22) to ensure that the system error is less than 0.01.
Blind spot management: The near-field scanning method requires attention to the pulse width setting. An excessively large pulse width will increase the blind spot and affect the positioning of short distance events.