In order to find the proper laser power that gives you the: a.) good signal height at maximal applied bias, but not near saturation of the amps b.) short pulse c.) good focus One needs to tune the following parameters: a.) Laser DAC (width and power of the pulse) - which needs to be as high as possible (different for different wavelengths), but still such that the laser is stable. b.) Amplifier bias (53 dB amp) which can be between 6-15 V, without degradation in bandwidth, but different amplification. Alternatively one can use a smaller 12 dB or 33 dB amplifiers. c.) Use of neutral density filters (preferred way of reducing the light intensity). Several filters can be used in series without degradation of focusing performance d.) Changing of iris opening, which however affects the focusing performance.