Stability

In addition to the power and beam quality, stability is an important characteristic for all laser systems. The stability of the 3500 is defined in terms of the short term (pulse-to-pulse) energy stability, and the long term (quasi-cw) power stability. In general, the short term behavior is determined primarily by the design of the system, whereas the long term behavior is the result of the sensitivity of the laser to the environment. As with most laser systems, users will see the best stability when the laser is operated in a temperature controlled environment.

CW Power Stability--Drift

Solid state lasers operate at a single specified power level for best stability. Over a long period of time the power will decline as a result of the gradual "fade" of the pump diode. This is typically over many thousands of hours, and is not measurable during routine operation. The fade associated with the Model 3500 is especially slow as the diodes are typically driven below their rated specification. Superimposed on the long term fade is the power drift, which is typically a function of the local temperature. The Model 3500 has an inherent power drift of less than +/- 5% over an 8 hour period when operated in a stable environment.
 

Pulse to Pulse Energy Stability All Model 3500 systems have a pulse-to-pulse energy stability specification of <10%. As the average pulse energy is dependent on the repetition rate of the laser, the pulse-to-pulse energy stability specification applies to a specific (user-defined) repetition rate.

". . .the Model 3500 is designed to. . . increase the lifetimes of the optical components of the laser and reduce beam distortion, while maintaining a factor of three to five times higher power then competing system designs."