Fine Optical Engineering Research Center

Chengdu, China

Fine Optical Engineering Research Center

Chengdu, China
Time filter
Source Type

Wang J.,Fine Optical Engineering Research Center | Li Y.,Fine Optical Engineering Research Center | Li Y.,Akita Prefectural University | Han J.,University of Sichuan | And 2 more authors.
Journal of the European Optical Society | Year: 2011

Hard brittle materials (e.g. glasses and ceramics) increasingly appeal to general interests because of their excellent physical, mechanical and chemical properties such as infer hardness and strength at extreme temperature and chemical stability. The precision manufacturing of these materials is primarily achieved by grinding and polishing, which generally employs abrasives to wear the materials. With this manufacturing technology, the materials are removed due principally to the fracture of brittle materials, which will leave a cracked layer on the surface of manufactured components, namely subsurface damage (SSD). The subsurface damage affects the strength, performance and lifetime of components. As a result, investigation into the subsurface damage is needed. A host of characterizing techniques have been developed during the past several decades. These techniques based on different mechanisms provide researchers with invaluable information on the subsurface damage in various materials. In this article the typical SSD evaluation techniques are reviewed, which are regularly used in optical workshops or laboratories.

Li Y.,Fine Optical Engineering Research Center | Li Y.,Akita Prefectural University | Wu Y.,Akita Prefectural University | Wang J.,Fine Optical Engineering Research Center | And 3 more authors.
Optics Express | Year: 2012

Ultrasonic vibration has been employed to improve the quality of machined surface in the grinding of brittle materials. In this report, we transplant the philosophy of ultrasonic vibration assisted grinding to chemo-mechanical bound-abrasive-pellet polishing in anticipation of the improvement in either surface roughness or material removal rate. The preliminary experimental results show that the ultrasonic vibration assisted chemo-mechanical pellet polishing can yield desired results that material removal rate can be significantly raised while surface roughness is not degraded. The experimental results also indicate different mechanisms between ultrasonic-vibration-assisted chemo-mechanical pellet polishing and conventional chemo-mechanical bound-abrasive polishing. © 2011 Optical Society of America.

Wang C.,Xiamen University | Wang C.,China Academy of Engineering Physics | Yang W.,Xiamen University | Wang Z.,Xiamen University | And 5 more authors.
Applied Optics | Year: 2014

The calculation of the dwell time plays a crucial role in polishing precision large optics. Although some studies have taken place, it remains a challenge to develop a calculation algorithm which is absolutely stable, together with a high convergence ratio and fast solution speed even for extremely large mirrors. For this aim, we introduced a self-adaptive iterative algorithm to calculate the dwell time in this paper. Simulations were conducted in bonnet polishing (BP) to test the performance of this method on a real 430 mm × 430 mm fused silica part with the initial surface error PV = 1741.29 nm, RMS = 433.204 nm. The final surface residual error in the clear aperture after two simulation steps turned out to be PV = 11.7 nm, RMS = 0.5 nm. The results confirm that this method is stable and has a high convergence ratio and fast solution speed even with an ordinary computer. It is notable that the solution time is usually just a few seconds even on a 1000 mm × 1000 mm part. Hence, we believe that this method is perfectly suitable for polishing large optics. And not only can it be applied to BP, but it can also be applied to other subaperture deterministic polishing processes. © 2014 Optical Society of America.

Fu Y.,Xihua University | Li Y.,Fine Optical Engineering Research Center
Journal of Optoelectronics and Advanced Materials | Year: 2014

Fixed-abrasive polishing of fused silica glass in conjunction with vibration under dry conditions was developed. Preliminary results show that material removal rate can be raised by up to >50% by applying vibration in fixed-abrasive polishing of fused silica. The likely reasons are reckoned to be outstanding capability of dispelling debris populated at the interface between polishing tool and glass, which is considered to hinder polishing process. On the other hand, surface roughness of polished fused silica is slightly degraded in vibration polishing compared to that without vibration. Certain periodical structure resulting from vibration appears on the machined surface, of which the spatial period is consistent with vibration. The mechanism of material removal in dry polishing is due probably to the synergy of chemical and mechanical effects between ceria and silica in polishing tool and workpiece, respectively. Ceria in the tool first bonds with silica to form Ce-O-Si systems under extreme pressure and then the Si-O de-bonds owing to the greater strength of the Ce-O; this way, debris forms and glass is polished.

Liao D.,Fine Optical Engineering Research Center | Xie R.,Fine Optical Engineering Research Center | Hou J.,Fine Optical Engineering Research Center | Chen X.,Fine Optical Engineering Research Center | Zhong B.,Fine Optical Engineering Research Center
Applied Surface Science | Year: 2012

A process based on chemical mechanical polishing has been proposed to polishing ultra-precision nonlinear optical crystal flats with high surface quality. An annular polyurethane pad was employed in the process. An excellent flatness of the annular polishing pad can be obtained using a special conditioner. The newly developed septum and holder system in the process has significantly reduced the rigid punch effect and workpiece/pad deflection brought by the spindle and carrier system in the common chemical mechanical polishing (CMP) process. In addition, the pre-strain of the pad by the septum can effectively eliminate the elastic response of the pad on the exterior of the workpiece and hence greatly reduce the stress concentration on the edge. The ACMP process is especially suitable for the final polishing of fragile crystals that have anisotropic properties and demand strict requirements on surface figure and defects. Crown Copyright © 2012 Published by Elsevier B.V. All rights reserved.

Liu Z.,Fine Optical Engineering Research Center | Luo J.,Fine Optical Engineering Research Center | Zheng Y.,Fine Optical Engineering Research Center | Ma P.,Fine Optical Engineering Research Center | And 4 more authors.
Optics Express | Year: 2014

The damage conversion behavior of high-reflection coatings under multiple shot of 1064nm nanosecond pulse laser has been investigated. The mechanism of initiation and evolution law of multi-shot damage has been revealed by use of surface profiler and focus ion beam with SEM. The scald damage tends to become delaminate damage under some certain condition. Huge experiments supports that this morphology change condition has a close connection with scald initial fluence, scald size, subsequent fluence and shot number. The relationship among these factors is for the first time achieved to offer the "safety lines" for components. The thermal accumulation effect on the decline of damage threshold under multi-shot has been studied in theory and verified experimentally. In addition, a theory-based formula is used to fit the experiment data for further prediction of thin film life-time. © 2014 Optical Society of America.

Luo J.,Fine Optical Engineering Research Center | Liu Z.,Fine Optical Engineering Research Center | Chen S.,Fine Optical Engineering Research Center | Ma P.,Fine Optical Engineering Research Center
Qiangjiguang Yu Lizishu/High Power Laser and Particle Beams | Year: 2013

The pulse width is different, the mechanism of the laser-matter interaction is different. Damage results from plasma formation and ablation for τ≤10 ps and from heat depositing and conventional melting for τ>100 ps. Two theoretical models of transparent dielectrics irradiated by multi-pulses laser are respectively developed based on the above-mentioned different mechanism. One is the dielectric breakdown model based on electron density evolution equation for femtosecond multi-pluses laser, the other is the dielectric heat-damage model based on Fourier's heat exchange equation for nanosecond multi-pluses laser. Using these models, the effects of laser parameters and material parameters on the laser-induced damage threshold of dielectrics are analyzed. The analysis results show that different parameters have different influence on the damage threshold. The effect of parameters on the multi -pulses damage threshold is not entirely the same to the single-pulse damage threshold. The multi-pulses damage mechanism of dielectrics is discussed in detail, considering the effect of different parameters. The discussion provides more information for understanding its damage process and more knowledge to improve its damage thresholds. And the relationship between damage threshold and pulse number is illustrated, it is in good agreement with experimental results. The illustration can help us to predict the multi-pulses damage threshold and the lifetime of optical components.

Li Y.,Fine Optical Engineering Research Center
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

The progress in the polishing of glass, in particular fused silica glass, with bound-abrasive is reviewed in the paper. The technique is rather successful in some respects, e.g. material removal rate, surface roughness, flatness of substrates. The surface roughness can be as low as <0.5nm (Ra) comparable with loose pad/pitch polishing for fused silica. On the other hand, the material removal rate is so high that the ground surface can be polished to specular (Ra:1∼2nm) within a quarter of an hour. The technique can be adapted to polish plane, spherical, aspheric surfaces and even free-form surface. The technique is next to free of subsurface damage after slightly wet chemical etching. Because ceria is utilized as abrasives and epoxy resin as binding materials softer than or comparable to fused silica, the shape of the polishing tools is easy to be shaped and dressed and need no truing. The technique may provide a potential solution to fast polishing of glass. © 2015 SPIE.

Zheng Y.,Fine Optical Engineering Research Center | Ma P.,Fine Optical Engineering Research Center | Li H.,Fine Optical Engineering Research Center | Liu Z.,Fine Optical Engineering Research Center | Chen S.,Fine Optical Engineering Research Center
Optics Express | Year: 2013

UV laser induced damage (LID) on exit surface of fused silica could cause modulation effect to transmitted beam and further influence downstream propagation properties. This paper presents our experimental and analytical studies on this topic. In experiment, a series of measurement instruments are applied, including beam profiler, interferometer, microscope, and optical coherent tomography (OCT). Creating and characterizing of LID on fused silica sample have been implemented. Morphological features are studied based on their particular modulation effects on transmitted beam. In theoretical investigation, analytical modeling and numerical simulation are performed. Modulation effects from amplitude, phase, and size factors are analyzed respectively. Furthermore, we have novelly designed a simplified polygon model to simulate actual damage site with multiform modulation features, and the simulation results demonstrate that the modeling is usable and representative. © 2013 Optical Society of America.

Liu Z.,Fine Optical Engineering Research Center | Chen S.,Fine Optical Engineering Research Center | Ma P.,Fine Optical Engineering Research Center | Wei Y.,Fine Optical Engineering Research Center | And 4 more authors.
Optics Express | Year: 2012

Damage tests are carried out at 1064nm to measure the laser resistance of TiO2/Al2O3and HfO2/Al 2O3 antireflection coatings grown by atomic layer deposition (ALD). The damage results are determined by S-on- 1 and R-on-1 tests. Interestingly, the damage performance of ALD coatings is similar to those grown by conventional e-beam evaporation process. A decline law of damage resistance under multiple irradiations is revealed. The influence of growth temperature on damage performance has been investigated. Result shows that the crystallization of TiO2 layer at higher temperature could lead to numerous absorption defects that reduce the laserinduced damage threshold (LIDT). In addition, it has been found that using inorganic compound instead of organic compound as precursors for ALD process maybe effectively prevent carbon impurities in films and will increase the LIDT obviously. © 2012 Optical Society of America.

Loading Fine Optical Engineering Research Center collaborators
Loading Fine Optical Engineering Research Center collaborators