High‐power polymer optical fiber amplifier

Organic dye‐doped polymer optical fiber amplifiers (POFA) are fabricated and their amplification characteristics are investigated. Rhodamine 6G, Rhodamine B, and Perylene Red are used as organic dyes for optical amplification. The amplification of optical signals at 571 nm, 591 nm, and 621 nm wavelengths is confirmed through pumping by the second harmonic of a pulse‐operated Nd: YAG laser. It is shown that very high output powers can be achieved by increasing the caliber of Rhodamine B doped POFA. One‐kW optical signal output (30 dB gain) is obtainable at dye doping of 1 ppm, 500‐μm core radius, and POFA length of 250 mm. The conversion efficiency of such a high output amplifier is 27 percent. The POFAs are advantageous over liquid‐dye lasers because they are easily handled. Multistage POFAs in the form of joint POFAs are proposed as new light source systems and their oscillation characteristics are discussed.