atmospheric and ocean optics|12 Article(s)
Strong intensity variations of laser feedback interferometer caused by atmospheric turbulence
Yiyi Sun, and Zhiping Li
The significant variation of the laser output can be caused by feedback of a small part of laser beam, which is reflected or backscattered by a target at a long distance from laser source, into the laser cavity. This paper describes and analyzes theoretically and experimentally the influence of atmospheric turbulence on interference caused by laser feedback. The influence depends upon both the energy of feedback into the laser cavity and the strength of turbulence over a laser propagation path in the atmosphere. In the case of stronger energy of feedback and weak turbulence variance of fluctuation of the laser output can be enhanced by hundreds to thousands times. From our measurements and theoretical analysis it shows thatthese significant enhancements can result from the change of laser-cavity-modes which can be stimulated simultaneously and from beat oscillations between a variety of frequencies of laser modes. This also can result from optical chaos inside the laser resonator because a non-separable distorted external cavity can become a prerequisite for optical chaos.
Chinese Optics Letters
  • Publication Date: Jan. 01, 1900
  • Vol.1 Issue, 5 05249 (2003)
Impact of organic contamination in vacuum on laser-induced damage threshold of TiO2/SiO2 dielectric mirrors
Yun Cui, Hua Yu, Yuanan Zhao, Yunxia Jin, Hongbo He, and Jianda Shao
The influence of organic contamination in vacuum on the laser-induced damage threshold (LIDT) of coatings is studied. TiO2/SiO2 dielectric mirrors with high reflection at 1064 nm are deposited by the electronbeam evaporation method and their LIDTs are measured in vacuum and atmosphere, respectively. It is found that the contamination in vacuum is easily attracted to optical surfaces because of the low pressure and becomes the source of damage, O2 molecules in vacuum with contamination can accelerate the laser-induced damage by observing LIDT and damage morphologies. LIDTs of mirrors have a little change in vacuum compared with in atmosphere when the organic contamination is wiped off. The results indicate that organic contamination is a significant reason to decrease the LIDT in vacuum.
Chinese Optics Letters
  • Publication Date: Jul. 22, 2019
  • Vol.5 Issue, 11 11680 (2007)
Partially coherent vortex beams propagation in a turbulent atmosphere
Yixin Zhang, Minxia Tang, and Chunkan Tao
Chinese Optics Letters
  • Publication Date: Jan. 01, 1900
  • Vol.3 Issue, 10 10559 (2005)