Single-stage Double-pass Bidirectional Pumped C+L Band ASE Broad-band Light Source

The application of C+L band broad-band ASE light source to laser communication apparatus test, fiber sensor, spectrum division light source, and fiber gyroscope was very important .Recently, with the rapid development of optical communication, ASE broad-band light source had been widely researched and applied. Meanwhile it became more mature in technology , and was commercialized gradually .In this paper, a new light source configuration called Single-stage Double-pass Bidirectional ASE broad-band light source was researched and then subjected to a theoretical simulation analysis thoroughly . Further more a new power supply for the LD was developed.The major content of the paper was as follows:(1) The development of ASE broad-band light source as well as the relative latest researches in and abroad, and the performance index of a series of commercialized products were introduced.(2) Analyzed The mechanism of the process that Er-doped fiber produced C and L band ASE .The evolvement equation of the ASE power and pumping power vs the length of optical fiber in Single-stage Double-pass Bidirectional ASE broad-band light source was presented respectively. In order to raise the experimental success rate and save cost, a simulated programme was compiled by Matlab. Then the transition process from C band to L band, the formation of the L band, C and L band were analyzed based on the simulation result. The simulation result was consistent with the experiment result.(3)The circuit modules of the LD power supply including commutate filter module, slowness circuit, the main power supply circuit for the LD, and cooling circuit were analyzed. The function and operation method of the modules were introduced. The SCH and PCB were designed by Protel DXP. Then the available circuit apparatus were chosen and the whole circuit setting and debugging was accomplished.(4)The Single-stage Double-pass bidirectional pumped broad-band ASE light source was studied by experiment, and the cause of the uneven output spectrum was analyzed. At last, the optimal spectrum was obtained. The spectrum is from 1525nm to 1602nm (77nm) ,the flatness is 6dB and the ASE output power is 19.7mW. The performance index reached the commercial standard .