| 摘要 |
An optical interrogation system (10) comprises optical amplifying and gating means, in the form of a semiconductor optical amplifier (SOA) (14) and an optical source (12, 14). Drive means (22) (an electrical pulse generator driven by a variable frequency oscillator) are provided to generate electrical drive pulses (see inset (a)) which are applied to the SOA (14), to cause the SOA (14) to switch on and off. The optical source comprises a superluminescent diode (SLD) (12), the CW output from which is gated into optical pulses by the SOA (14). The SOA (14) is optically coupled to the waveguide (16) containing an array of reflective optical elements (gratings G) to be interrogated. The interrogation system further comprises optical detection means (18), optically coupled to the SOA (14), operable to evaluate the wavelength of a returned optical pulse transmitted by the SOA (14). |
