We have performed an experimental study of the power scaling ability of a fiber amplifier limited by the temporal stability of its seed light. Three seed sources with various temporal characteristics are demonstrated for the fiber amplifier. An accurate model of the fiber amplifier is established by considering the time dynamics of the laser. The results show that the self-pulsation can reduce the SRS threshold of the fiber amplifier and limit the power scalability of the fiber amplifier.

No abstract

No abstract

We propose a precise rolling angle measurement for a collimator to extend its application in 3D angular deformation measurement, with performance significantly superior to that of the traditional 2D technique. The rolling angle measurement is realized by taking full advantage of the point array image, which is projected in terms of the collimated beam. The measurement error is estimated according to the proposed algorithm. The characteristics of the point array are analyzed to optimize the point array for precise measurement, including the point distribution, the point array resolution, and the point array area. Both simulations and experiments demonstrate that subarcsecond precision rolling angle measurement is achieved by our method, which is superior to those attained by other proposed targets.

No abstract