Ultra-short-pulse laser frequency-doubled continuous attenuator

Abstract

The invention discloses an ultra-short-pulse laser frequency-doubled continuous attenuator, which comprises an optical system, a liquid crystal modulator, a liquid crystal voltage control system, a focusing device and a frequency-doubled crystal. The optical system is used for performing beam expanding on an ultra-short-pulse laser and dividing the laser into at least four beams of parallel light; the liquid crystal modulator is used for performing phase modulation on one beam of parallel light; the liquid crystal voltage control system is used for adjusting voltage applied to the liquid crystal modulator; and the focusing device and the frequency-doubled crystal are used for performing focusing and frequency doubling on the modulated parallel light. In the ultra-short-pulse laser frequency-doubled continuous attenuator, the sum frequency effect of the ultra-short-pulse laser is utilized to modulate frequency-doubled light intensity thereof; and in the process of generating frequency-doubled light by the ultra-short-pulse laser, the frequency-doubled efficiency in the frequency-doubled crystal is controlled so as to realize continuous modulation on the frequency-doubled light intensity of the ultra-short-pulse laser. The ultra-short-pulse laser frequency-doubled continuous attenuator has the advantages of simple structure, capability of preventing the pulse widths and shapes of pulsed light from being changed, uniform light spot quality, no damage to attenuation devices and capability of performing continuous adjustment on the strength of ultra-short pulses.

Description

technical field [0001] The invention relates to the field of generation and adjustment of ultrashort laser nonlinear frequency doubling, in particular to an ultrashort pulse laser frequency doubling continuous attenuator. Background technique [0002] Since its inception, laser technology has been developing towards high power, short pulse width, wide wavelength tuning range, miniaturization and full curing. Ultrashort pulse laser is one of the most powerful new tools for scientific research provided by the development of laser technology in recent years. Ultrashort pulse laser refers to pulse laser with pulse width in the range of picoseconds to femtoseconds or even attoseconds. The application range of ultrashort light pulses ranges from the testing of ultra-high-speed semiconductor devices to the precise processing of materials, from exciting and tracking chemical reactions to complex ophthalmology and neurosurgery applications, etc. Ultrashort pulses allow people to fo...

AI Technical Summary

Problems solved by technology

Various existing adjustment methods mainly pass the generated ultra-short frequency multiplied pulse light through the attenuation device, and the usual light intensity attenuation (modulator) device includes various attenuation plates, polarizers, gratings, liquid crystals, etc. Due to the dispersion or absorption effect, the intensity modulation of the ultrashort frequency doubled light often causes the change of its pulse width and shape, which will have an adverse effect on its application.

Due to its extremely short pulse length, and the continuous attenuation film of absorption will cause the spot quality to be uneven

Due to the extremely strong pulse peak power of the ultrashort laser, it often causes certain damage to the attenuation device

Moreover, since the fundamental frequency light and the frequency doubled light are generally transmitted collinearly, filters or gratings are often required to separate each other, which increases the complexity of the optical system. Adjustment

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