The laser-induced damage threshold(LIDT) of optical coating is a limited factor for development of a high peak power laser. The automatic damage testing facility was built to determine the LIDT of optics at 1 064 nm a...The laser-induced damage threshold(LIDT) of optical coating is a limited factor for development of a high peak power laser. The automatic damage testing facility was built to determine the LIDT of optics at 1 064 nm and 355 nm.. The cleanning and processing procedure of the substrate and coating technique were improved, and the damage resistance of high-reflective coating at 1 064 nm was increased.展开更多
The chemical structures, optical properties and laser-induced damage thresholds of magnesium fluoride films annealed at different temperatures were investigated. The results showed that the stoichiometry of MgF2 film ...The chemical structures, optical properties and laser-induced damage thresholds of magnesium fluoride films annealed at different temperatures were investigated. The results showed that the stoichiometry of MgF2 film changed a little with the increase in annealing temperature. Analysis of the optical properties indicated that excellent antireflection behavior of the film in the range of 200-400 nm can be obtained by the samples coated with MgF2 film. The refractive index increased and the extinction coefficient decreased with increasing annealing temperature. Compared with the asdeposited films, the laser-induced damage threshold was improved after annealing process and decreased with the increase in annealing temperature, which was probably due to the denser film and more absorption centers under higher annealing temperature.展开更多
High laser-induced damage threshold and large aperture were focuses on the studies of high power laser coatings. This paper reports the research activities at our center. Several measures were developed for evaluating...High laser-induced damage threshold and large aperture were focuses on the studies of high power laser coatings. This paper reports the research activities at our center. Several measures were developed for evaluating characters of laser damage, including determination of laser induced damage threshold and detection of absorption based on surface thermal lensing technique. Defect was deemed to be the initial source of laser damage, and was the main factor restricting the laser damage resistance of optical coatings. The contribution of several kinds of typical defects to laser damage was analyzed, and some deposition measures were adopted to control and eliminate the origin of defect. Furthermore, some post-treatment methods were also employed to alleviate the influence of the defect and to improve the laser damage resistance. Correction mask was introduced to improve the thickness uniformity, and the thickness uniformity can be amended to less than 1% in the range of Φ650 mm. Preliminary investigation related to surface deformation was also conducted.展开更多
The design,fabrication and performance of narrow-band rugate minus filters are investigated in this paper.A method of fabricating graded-index coatings by rapidly alternating deposition of low(Si O_(2))and high(Al_(2)...The design,fabrication and performance of narrow-band rugate minus filters are investigated in this paper.A method of fabricating graded-index coatings by rapidly alternating deposition of low(Si O_(2))and high(Al_(2)O_(3))refractive index materials is presented to fabricate a rugate structure.The narrow-band rugate minus filter design and fabrication approaches are discussed in detail.The experimental results,including transmittance spectrum,surface damage test and damage morphology investigated with a scanning electron microscope,demonstrate the high performance of the as-fabricated spatial filter and confirm the feasibility of the fabrication method for narrow-band rugate minus filters.展开更多
1 064 nm, 532 nm frequency-doubled antireflection （AR） coatings with buffer layer of SiO2 between the coating and the substrate were fabricated by the electron beam evaporation technology on the substrate of lithium...1 064 nm, 532 nm frequency-doubled antireflection （AR） coatings with buffer layer of SiO2 between the coating and the substrate were fabricated by the electron beam evaporation technology on the substrate of lithium triborate （LiB3O5 or LBO） crystals. The residual reflectance of the sample is 0.07% and 0.11% at 1 064 nm and 532 nm, respectively. The adhesion and the laser-induced damage threshold （LIDT） of the sample are greater than 200 mN and 18.6 J/cm2. The strengthening mechanism of adhesion and LIDT of the buffer layer of SiO2 were discussed by considering full plastic indentation and shear theory, and spallation of a plated film induced by thermal shock stress, respectively.展开更多
Rare earth doped B2O3-Al2O3-SiO2 glass （RExBAS, x=5, 10, 20; RE=La, Sm） were prepared by solid state reaction method. Optical transmission spectra of such glass were characterized by ultraviolet spectrometers, and 1...Rare earth doped B2O3-Al2O3-SiO2 glass （RExBAS, x=5, 10, 20; RE=La, Sm） were prepared by solid state reaction method. Optical transmission spectra of such glass were characterized by ultraviolet spectrometers, and 1064 nm laser induced damage performance was investigated through the method of ＂1-on-1＂. The results indicated that there was a strong absorptive peak near 1064 nm in SmxBAS glass, the peak was enhanced with increasing x. While LaxBAS glass was transparent to 1064 nm laser, at the same time, the results of laser induced damage showed that the anti-laser induced damage performance of such glass was strengthened with the addition of rare earth oxide. Furthermore, the laser induced damage threshold （LIDT） of SmxBAS glass was significantly higher than that of LaxBAS glass. Consequently, Sm^3＋ doping was favor in the improvement of anti-laser induced damage performance for BAS glass.展开更多
The study of infrared nonlinear optical(NLO)materials with wide band gaps and high laser induced damage thresholds(LIDTs)is an urgent and challenging topic.Here,we report the NLO properties of CsRESiS_(4)(RE=Sm,Gd–Ho...The study of infrared nonlinear optical(NLO)materials with wide band gaps and high laser induced damage thresholds(LIDTs)is an urgent and challenging topic.Here,we report the NLO properties of CsRESiS_(4)(RE=Sm,Gd–Ho),which were synthesized by the reactive flux CsCl assisted RExOy–B–S routine.The structure of CsRESiS_(4),[CsS_(7)]pentagonal bipyramids are orderly arranged to populate the interlayer space created by[RES_(7)]monocapped triangular prisms consolidated[SiS_(4)]tetrahedra.They all exhibit wide band gaps of 3.51–3.95 eV,high LIDTs of 3.6–5.5×AGS,and NLO activity,with CsHoSiS_(4)possessing the largest band gap among rare-earth chalcogenides.The theoretical calculation results indicate that[RES_(7)]monocapped triangular prisms are the main source of NLO activity and have a wide band gap.This work provides an effective case for exploring wide band gap infrared NLO materials.展开更多
文摘The laser-induced damage threshold(LIDT) of optical coating is a limited factor for development of a high peak power laser. The automatic damage testing facility was built to determine the LIDT of optics at 1 064 nm and 355 nm.. The cleanning and processing procedure of the substrate and coating technique were improved, and the damage resistance of high-reflective coating at 1 064 nm was increased.
基金financially supported by the Research Fund of the State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,China(Grant No.155-QP-2016)the Fundamental Research Funds for the Central Universities(No.3102014JCQ01032)the 111 Project(No.B08040)
文摘The chemical structures, optical properties and laser-induced damage thresholds of magnesium fluoride films annealed at different temperatures were investigated. The results showed that the stoichiometry of MgF2 film changed a little with the increase in annealing temperature. Analysis of the optical properties indicated that excellent antireflection behavior of the film in the range of 200-400 nm can be obtained by the samples coated with MgF2 film. The refractive index increased and the extinction coefficient decreased with increasing annealing temperature. Compared with the asdeposited films, the laser-induced damage threshold was improved after annealing process and decreased with the increase in annealing temperature, which was probably due to the denser film and more absorption centers under higher annealing temperature.
文摘High laser-induced damage threshold and large aperture were focuses on the studies of high power laser coatings. This paper reports the research activities at our center. Several measures were developed for evaluating characters of laser damage, including determination of laser induced damage threshold and detection of absorption based on surface thermal lensing technique. Defect was deemed to be the initial source of laser damage, and was the main factor restricting the laser damage resistance of optical coatings. The contribution of several kinds of typical defects to laser damage was analyzed, and some deposition measures were adopted to control and eliminate the origin of defect. Furthermore, some post-treatment methods were also employed to alleviate the influence of the defect and to improve the laser damage resistance. Correction mask was introduced to improve the thickness uniformity, and the thickness uniformity can be amended to less than 1% in the range of Φ650 mm. Preliminary investigation related to surface deformation was also conducted.
基金Project supported by the Postdoctoral Science Foundation of China(Grant Nos.2016M592528 and 2016M602517)the Natural Science Foundation of Guangdong Province,China(Grant No.2017A030310130)the National Natural Science Foundation of China(Grant No.11705259)
文摘The design,fabrication and performance of narrow-band rugate minus filters are investigated in this paper.A method of fabricating graded-index coatings by rapidly alternating deposition of low(Si O_(2))and high(Al_(2)O_(3))refractive index materials is presented to fabricate a rugate structure.The narrow-band rugate minus filter design and fabrication approaches are discussed in detail.The experimental results,including transmittance spectrum,surface damage test and damage morphology investigated with a scanning electron microscope,demonstrate the high performance of the as-fabricated spatial filter and confirm the feasibility of the fabrication method for narrow-band rugate minus filters.
基金Funded by the Doctorial Start-up Fund of the Department of Science and Technology of Liaoning Province (20081030)
文摘1 064 nm, 532 nm frequency-doubled antireflection （AR） coatings with buffer layer of SiO2 between the coating and the substrate were fabricated by the electron beam evaporation technology on the substrate of lithium triborate （LiB3O5 or LBO） crystals. The residual reflectance of the sample is 0.07% and 0.11% at 1 064 nm and 532 nm, respectively. The adhesion and the laser-induced damage threshold （LIDT） of the sample are greater than 200 mN and 18.6 J/cm2. The strengthening mechanism of adhesion and LIDT of the buffer layer of SiO2 were discussed by considering full plastic indentation and shear theory, and spallation of a plated film induced by thermal shock stress, respectively.
基金the Natural Science Fund of Jangsu Provinence (BK2004121) Trans-Century Training Programme Foundation for the Talents by the Chinese Ministry of Education
文摘Rare earth doped B2O3-Al2O3-SiO2 glass （RExBAS, x=5, 10, 20; RE=La, Sm） were prepared by solid state reaction method. Optical transmission spectra of such glass were characterized by ultraviolet spectrometers, and 1064 nm laser induced damage performance was investigated through the method of ＂1-on-1＂. The results indicated that there was a strong absorptive peak near 1064 nm in SmxBAS glass, the peak was enhanced with increasing x. While LaxBAS glass was transparent to 1064 nm laser, at the same time, the results of laser induced damage showed that the anti-laser induced damage performance of such glass was strengthened with the addition of rare earth oxide. Furthermore, the laser induced damage threshold （LIDT） of SmxBAS glass was significantly higher than that of LaxBAS glass. Consequently, Sm^3＋ doping was favor in the improvement of anti-laser induced damage performance for BAS glass.
基金support by the National Natural Science Foundation of China(22265014,22371246)the Yunnan Fundamental Research Projects(202401AS070120)+2 种基金the Natural Science of Foundation of Jiangxi Province(20242BAB26034)the Key Laboratory of Jiangxi Province for Special Optoelectronic Artificial Crystal Materials(20242BCC32037)the Science and Technology Project of Jiangxi Provincial Department of Education(GJJ2201602).
文摘The study of infrared nonlinear optical(NLO)materials with wide band gaps and high laser induced damage thresholds(LIDTs)is an urgent and challenging topic.Here,we report the NLO properties of CsRESiS_(4)(RE=Sm,Gd–Ho),which were synthesized by the reactive flux CsCl assisted RExOy–B–S routine.The structure of CsRESiS_(4),[CsS_(7)]pentagonal bipyramids are orderly arranged to populate the interlayer space created by[RES_(7)]monocapped triangular prisms consolidated[SiS_(4)]tetrahedra.They all exhibit wide band gaps of 3.51–3.95 eV,high LIDTs of 3.6–5.5×AGS,and NLO activity,with CsHoSiS_(4)possessing the largest band gap among rare-earth chalcogenides.The theoretical calculation results indicate that[RES_(7)]monocapped triangular prisms are the main source of NLO activity and have a wide band gap.This work provides an effective case for exploring wide band gap infrared NLO materials.
