We have investigated the influence of the oscillator beam (the polarization beam) on the small-signal gain and saturation energy of an oscillator-amplifier dye laser transversely pumped by a frequency-doubled Nd:YAG laser. We found that the amplifier relation for this laser agrees with Frantz and Nodvik's model. (C) 2010 Society of Photo-Optical Instrumentation Engineers. [DOI: 10.1117/1.3488048]