Femtosecond laser speckles

The concept of femtosecond laser speckles is put forward. The theory of a speckle pattern in light of finite bandwidth is applied to describe femtosecond laser speckles. Basic representations of the contrast and the spectral correlation of femtosecond laser speckles are presented. The relationship between the speckle contrast and the bandwidth of a femtosecond laser is given. Experimental results are given that indicate an obvious difference between the speckle patterns produced by a continuous-wave laser and those produced by a femtosecond laser. (c) 2005 Optical Society of America