Multi-frame observation of a single femtosecond laser pulse propagation using an echelon and optical polarigraphy technique

We developed a multiframe observation method of femtosecond laser pulse propagating in transparent medium based on optical polarigraphy technique. An echelon was introduced into the probe light and divided it into multipulses both in time and space, allowing a multiframe detection of the intense laser pulse propagating in materials. Using this method, we realized a multiframe observation of a single femtosecond laser pulse propagating in CS2 with ultrafast self-modulation such as filamentation. This imaging method has been demonstrated to be of a femtosecond time resolution and a frame rate of ∼ THz.