Wavelength distribution optical fiber sensor

The fundamental principles and characteristics of wavelength distribution optical fiber sensors are described. An optical fiber sensor is used to count railway tickets. This sensor adapts line array optical fiber receivers and two-wavelength difference measurements, thereby greatly decreasing the requirement on light source brightness and steadiness. The system's sensibility and anti-interference ability have been improved at the same time. Compared with traditional inductive touch--needle counter techniques, it has more reliability and high-frequency counting response, and the measurement is contactless.