Miniaturized linear femtosecond laser pulse shape and width measurement device

Abstract

Provided is a miniaturized linear femtosecond laser pulse shape and width measurement device, which comprises a four-hole diaphragm plate, an attenuation time-delay sheet, a first convex lens, a third-order non-linear medium, a second convex lens, an optical fiber coupler, a single-mode fiber and a spectrometer, which are arranged in sequence in the beam incident direction of a pulse to be measured. Interference fringes are subjected to analysis and processing through a Fourier transform spectral interference method to reconstruct spectral and phase information of the light to be measured, thereby restoring shape and phase of the pulse to be measured and realizing measurement of shape and width of the femtosecond pulse. The device is based on the characteristic of rectilinear propagation of the light, and has the advantages of being compact in structure, firm and easy to adjust.

Description

technical field [0001] The invention relates to the time-domain pulse shape and phase measurement of femtosecond laser pulses, in particular to a miniaturized linear femtosecond laser pulse shape width measurement device. Background technique [0002] In 1991, Spence et al. invented the Kerr lens mode-locked (KLM) Ti:sapphire femtosecond laser using Ti:sapphire as the gain medium by using the Kerr effect, which greatly promoted the development of femtosecond technology. As this technology is more and more widely used in various fields such as medicine, processing, biology, and chemistry, the measurement of its pulse width has also become a technical problem. At present, the commonly used femtosecond pulse measurement techniques are: Frequency-resolved Optical Switching (FROG) and Self-Referencing Spectral Coherent Reconstruction (SPIDER). Both can obtain the amplitude and phase information of ultrashort pulses at the same time, but the pulse reconstruction process of FROG ...

AI Technical Summary

Problems solved by technology

Both can obtain the amplitude and phase information of ultrashort pulses at the same time, but the pulse reconstruction process of FROG requires multiple algorithm iterations, the calculation is complex, and it is difficult to measure in real time; SPIDER combines spectral coherence and spectral side-cutting methods to real-time pulse measurement, but its structure is complex, and the use of polarization elements introduces dispersion and phase matching conditions of nonlinear optical crystals limit the bandwidth

[0004] However, the previous measurement devices using FROG, SPIDER and SRSI methods all need to turn the optical path, which in turn requires complex optical path adjustments

Images