2022
2022
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Record 409 of
Title:Polydopamine functionalized graphene oxide for high sensitivity micro-tapered long period fiber grating sensor and its application in detection Co2+ ions
Author(s):Kang, Xin(1); Wang, Ruiduo(2); Jiang, Man(1); Li, Erkang(1); Li, Yarong(1); Yan, Xiaoxin(1); Wang, Tianqi(1); Ren, Zhaoyu(1)Source: Optical Fiber Technology Volume: 68 Issue: DOI: 10.1016/j.yofte.2021.102807 Published: January 2022Abstract:We report a highly sensitive label-free chemical sensor for the detection of heavy metal ions. The sensor was derived from a micro-tapered long-period fiber grating (MTLPFG) functionalized by graphene oxide and poly-dopamine modified graphene oxide, respectively. Because of the combination of chemical bonding and optical tweezer effect, the materials were deposited on the MTLPFG fiber grating surface. The morphology and elemental composition of the nanocomposites were characterized by scanning electron microscope, Fourier-transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). Herein, we demonstrate a high sensitivity MTLPFG detection of cobalt ions in a large concentration range from 1 ppb to 107 ppb. The highest sensitivity of 2.4 × 10?3 dB?ppb?1 at the PDA concentrations of 0.05 g?L?1 was obtained by MTLPFG functionalized with PDA-GO (PDA-GO-MTLPFG). The result was significantly higher than GO-deposited MTLPFG (GO-MTLPFG). The proposed PDA-GO-MTLPFG demonstrates superior application value in chemical sensing fields. ? 2021 Elsevier Inc.Accession Number: 20220111414607 -
Record 410 of
Title:Athermalization design of compact dual-fields middle infrared optical zoom system with high-speed switching
Author(s):Mei, Chao(1); Fei, Jia-Qi(1); Ma, Ying-Jun(1); Zhang, Hong-Wei(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 12166 Issue: DOI: 10.1117/12.2612267 Published: 2022Abstract:Mid-wave infrared imaging has the advantages of all day, high resolution, strong adaptability to the environment, so it is widely used. In high-speed target tracking and aiming. The target flying speed is extremely fast and the DOF (depth of field) of the fixed focal lens is limited, so the zoom lens is required. In order to ensure that the tracking target will not be lost, a fast zoom requirement of no more than 0.3s is proposed. According to the requirements, a compact athermalized mid-wave infrared dual field fast zoom lens is designed. The focal length is 400 mm and 200 mm, and the passive athermalization design is adopted which can meet the working temperature of-40° to + 60°. the lens can match the cooling detector with effective pixel of 640 × 512, size of 15 μm and F/4.The volume of the detector can be controlled in the range of L (196mm) × w (116mm) × H (185mm). The zoom group structure is considered in the design, and the switching time is less than 0.12s, and the image plane is stable when the zoom group switching. ? COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.Accession Number: 20220911734806 -
Record 411 of
Title:Observation of Primary and Secondary Enhancement of Emission Spectra From Spatially Confined Laser-Induced Aluminum Plasmas
Author(s):Xu, Boping(1,2); Lei, Bingying(1,2); Wang, Jing(1,2); Liu, Yinghua(1,2); Xing, Yufei(3); Xie, Xiaotao(3); Zhang, Wenfu(1); Tang, Jie(1); Wang, Yishan(1); Zhao, Wei(1); Duan, Yixiang(1,4)Source: IEEE Photonics Journal Volume: 14 Issue: 2 DOI: 10.1109/JPHOT.2022.3159720 Published: April 1, 2022Abstract:In this study, four cylindrical cavities with diameters of more than 10 mm are utilized to confine aluminum plasmas to improve the signal intensities of laser-induced breakdown spectroscopy (LIBS). Primary and secondary enhancements of spectra are observed. This phenomenon is attributed to the fact that plasmas are compressed into a smaller core area with denser population of excited atoms by reflected shockwaves more than one time. The delay time for both primary and secondary signal enhancements is postponed with decreasing the laser energy or increasing the cavity diameter. Relative standard deviations (RSDs) of spectra signal in different experimental conditions are discussed to illustrate the uncertainties of measurement. In addition, enhancement factor, signal-to-background ratio (SBR) and signal-to-noise ratio (SNR) are also examined in the two cases. The fast images of plasma plume further prove the enhancements of emission intensity, as well as its RSD. ? 2009-2012 IEEE.Accession Number: 20221211818051 -
Record 412 of
Title:Current Application and Progress of Laser Technology in Ophthalmology
Author(s):Li, Li(1); Zhang, Yue(1); Li, Mengxi(1); Zhang, Zhen(1); Dang, Yufei(1); Yang, Yanlong(2)Source: Zhongguo Jiguang/Chinese Journal of Lasers Volume: 49 Issue: 5 DOI: 10.3788/CJL202249.0507103 Published: March 10, 2022Abstract:Significance Recently, laser technology has made great progress, particularly its clinical application in ophthalmology, from the diagnosis and treatment to the surgery of various eye diseases. While these wide applications or emerging technologies have shown effective and safe results, there are still difficulties and challenges to overcome. Therefore, it is necessary to review the current application and progress of laser technology in ophthalmology, through which we can get inspired and further advance and optimize laser technology and its application in the diagnosis and treatment of eye diseases. The eye consists of the eyeball and its appendages ( eyelid, orbit, conjunctiva, lacrimal apparatus, and extraocular muscle). The application of laser in ocular appendage is similar to that of laser in dermatology, which produces a transient high temperature and vaporizes the tissue for treatment. Meanwhile, the eyeball, the optical component of the eye, features the application of laser in ophthalmology. The special structure of the eyeball makes it an optimal model for laser technology applications. The eyeball is composed of the ocular wall and the contents inside it. From the outermost part, the ocular wall includes the outer cornea and sclera, the middle uvea, which is rich in its vascular network, and the inner retina, where the photoreceptor cells reside. From front to back, eye contents include aqueous humor, lens, and vitreous body. The cornea, as well as all three eye contents, constitutes the refractive system of the eyeball. The normal visual function of the eye requires a transparent refractive system and a well-functioning chorioretinal vascular system. Therefore, the application of laser technologies is mainly focused on the diagnosis and treatment of two abovementioned components (the refractive and chorioretinal vascular systems), which is also the main topic of this paper. Different laser-tissue interaction mechanisms are exploited in laser-based ophthalmology instruments, including photodisruption, photocoagulation, and photochemical. The application of laser technology in the diagnosis and curative effect monitoring of ocular diseases includes in vivo confocal microscopy, scanning laser ophthalmoscopy, and optical coherence tomography. The application of laser technology for treating eye diseases includes corneal diseases, cataracts, glaucoma, and retinal choroidal diseases. The treatment of corneal diseases mainly includes excimer laser keratectomy, femtosecond laser-assisted in situ keratomileusis, and laser thermokeratoplasty. Cataract is treated using FSL-assisted cataract surgery (FLACS) and Nd: YAG laser posterior capsulotomy. The application of laser in glaucoma is to relieve pupil block between anterior and posterior chambers to increase the function of the trabecular meshwork to drain aqueous humor, thereby improving the entrance of the anterior chamber angle and reducing the outflow resistance. In the applications of treating retinal choroidal diseases, laser thermotherapy (fundus laser photocoagulation and transpupillary thermotherapy) and laser photodynamic therapy (photodynamic therapy) are always exploited. Progress With precision, convenience, remote operation, and low cost as its development trends, the application of laser in ophthalmology has made great progress in the following aspects. Precision means better vision, lower laser-related damage, and more effective biological regulation at the subcellular level with low-level laser therapy. With respect to corneal transplant surgery, the laser helps to achieve more accurate corneal cuts, which contributes to reduced astigmatism and better visual quality. Besides, with the assistance of adaptive optics and wavefront aberration technology, supernormal vision (visual acuity of >2.0) can be achieved in corneal refractive surgery, and low-level laser therapy can improve mitochondrial function and plays a protective role for retinal ganglion and photoreceptor cells, which trigger a series of physiological and biochemical reactions without inducing irreversible damage to the tissue. With respect to glaucoma, several more convenient laser therapies have been developed. MicroPulse? transscleral laser therapy (MicroPulse? TLT) has a wider range of indications and fewer complications compared with traditional transscleral ciliary photocoagulation, which can only be used for advanced refractory glaucoma without functional vision. Simultaneously, noncontact direct selective laser trabeculoplasty (DSLT) has been achieved to enforce the noninvasive, noncontact, and remote-operated treatment of glaucoma. Regarding the application of laser in cataract surgery, much attention is paid to circular curvilinear capsulorhexis, which is the key step in cataract surgery. Precision pulse capsulotomy and selective laser capsulotomy are the two representative techniques, which have better cost-effectiveness than FLACS. Conclusion and Prospect In summary, the application of ophthalmic laser technology covers various diseases of the anterior and posterior segments, from diagnosis to treatment. With the breakthrough of laser technology and increasing ophthalmology clinical demand, laser technology of diagnosis and treatment will be continuously optimized. This paper summarizes the applications of laser technology in the eye, and future challenges of different ophthalmology instruments, hoping to guide the breakthrough point of future technology. ? 2022 Science Press. All rights reserved.Accession Number: 20224513074088 -
Record 413 of
Title:Triple-wavelength quantitative phase imaging with refractive index measurement
Author(s):Song, Jinwei(1,2); Min, Junwei(1,3); Yuan, Xun(1,2); Xue, Yuge(1,2); Bai, Chen(1); Yao, Baoli(1,2,3)Source: Optics and Lasers in Engineering Volume: 156 Issue: DOI: 10.1016/j.optlaseng.2022.107110 Published: September 2022Abstract:A method to quantitatively measure the refractive index (RI) and the topography of transparent samples is proposed. Three quantitative phase images at different wavelengths are firstly obtained by using a quadriwave lateral shearing interferometry (QLSI) technique, and then the RIs at the three wavelengths and the physical thickness distribution of the sample are independently calculated with the help of Cauchy's dispersion formula. Neither the highly dispersive medium nor the manual operation of changing the surrounding medium is required. From the measured RIs, the composition of the sample can be identified besides the topography of the sample. Both simulation and experimental results verified the effectiveness and feasibility of the proposed method. ? 2022Accession Number: 20222912362200 -
Record 414 of
Title:Comparative study on the copper plasma confined with upward and downward conical cavities in laser-induced breakdown spectroscopy
Author(s):Xu, Boping(1,2); Liu, Yinghua(1,2); Lei, Bingying(1,2); Wang, Jing(1,2); Zhang, Wenfu(1,2); Wang, Yishan(1); Zhao, Wei(1); Duan, Yixiang(3); Tang, Jie(1,2)Source: Spectrochimica Acta - Part B Atomic Spectroscopy Volume: 197 Issue: DOI: 10.1016/j.sab.2022.106528 Published: November 2022Abstract:In this study, the confinement effects of upward and downward conical cavities on laser-induced copper plasma were investigated by optical emission spectroscopy and fast imaging technique. It follows from the time-integrated spectra, the time-resolved spectra, and the spatial distributions of spectral intensity that the superior enhancement effects on spectral intensity are obtained in the upward conical cavity. Compared to the plasmas without confinement, plasma temperature and electron number density are increased in the presence of upward conical cavity, while no enhancements are obtained in the downward conical cavity. Reflection model of shockwave in a conical cavity is established to interpret these phenomena. The enhancement of the plasma plume confined in the upward conical cavity results from the compression of the plume towards its central region by the shockwave, as well as the accelerated collisions between the particles therein. No enhancement effect of the plasma in the downward conical cavity is obtained because of the radial expansion of plasma plume and the population reduction of excited species in the plasma primary core due to the pressure of oblique downward shockwave. This shockwave reflection model is further verified by the fast imaging, where the direct observation of the plasma plume agrees well with the enhancement effects of the two cavities on the spectral intensity. ? 2022 Elsevier B.V.Accession Number: 20223812763830 -
Record 415 of
Title:Hilbert Transformation Deep Learning Network for Single-Shot Moiré Profilometry
Author(s):Ma, Pu(1); Du, Hubing(1); Ma, Yueyang(1); Zhang, Gaopeng(2); Wang, Feng(2); Zhao, Zixin(3); Feng, Leijie(1)Source: SSRN Volume: Issue: DOI: 10.2139/ssrn.4089088 Published: April 21, 2022Abstract:Phase demodulation from a single moiré fringe pattern is an ill-posed inverse problem, which limits the applications of moiré profilometry in dynamic 3D measurement. In this paper, a deep learning-based high-precision technique is used to tackle this problem arose from highly under sampled inputs. Our novel approach, to the best of our knowledge, termed 2D Hilbert transformation network, uses two Res U-Net networks paired with a dichotomous network to generate the desiredπ∕2 phase-shifting fringe pattern referred to the input. This process can be viewed as 2D Hilbert transformation of a fringe pattern. With this network, the wrapped phase can be extracted easily if the sampled fringes pattern is filtered and normalized in advance. Trained using simulated data, experimental results show that the proposed Hilbert transformation network provides a simple but robust solution for phase extraction from a single fringe pattern with phase error less than 0.02rad and, therefore, make it allow for paving a new way to reliable and practical learning-based single-shot Moiré profilometry. ? 2022, The Authors. All rights reserved.Accession Number: 20220086245 -
Record 416 of
Title:Influence of initial tunneling step on the return energy of high-order harmonic generation
Author(s):Gao, Xu-Zhen(1,2,3); Landsman, Alexandra S.(4); Cao, Huabao(1,3); Zhang, Yanpeng(2); Wang, Yishan(1,3); Fu, Yuxi(1,3); Pi, Liang-Wen(1,3)Source: Physical Review A Volume: 106 Issue: 5 DOI: 10.1103/PhysRevA.106.053105 Published: November 2022Abstract:To investigate high-order harmonic generation in a monochromatic laser field, we derive an analytical expression for the return energy of an electron as a function of the time interval between ionization and return. We then expand the expression for kinetic energy to second order with respect to the Keldysh parameter γ. In this expansion, the zero-order term is the return energy in the simple man model and the second-order term corresponds to corrections to this model. The origin of this additional kinetic energy is frequently attributed to the nonzero exit of the initial tunneling step. Here, we show that this commonly used picture is incomplete. We present a framework to fully understand the additional kinetic energy as resulting from additive contributions of zero-order and second-order velocities. Our results show that the nonzero velocity of the initial tunneling step has a quantifiable effect on the cutoff energy measured in high harmonic generation (HHG). This opens the door to experimentally addressing the question of the initial electron velocity at the tunnel exit, with important implications for the correct calibration of the attoclock, as well as our interpretation of the strong field-ionization process more broadly. ? 2022 American Physical Society.Accession Number: 20224713144708 -
Record 417 of
Title:Generation of separation-locked bound solitons in a passively mode-locked all-fiber laser with a Fabry-Perot microcavity
Author(s):Li, Wenlei(1,2); Li, Xiaoliang(1); Geng, Gaoli(1); Lin, Ruping(1); Chen, Guangwei(3); Wang, Guomei(4); Zeng, Chao(5); Wang, Xinliang(1)Source: Optics and Laser Technology Volume: 150 Issue: DOI: 10.1016/j.optlastec.2022.107936 Published: June 2022Abstract:We report the generation of separation-locked bound solitons in a passively mode-locked all-fiber laser with a Fabry-Perot (F-P) microcavity. The laser cavity can deliver several kinds of bound solitons with the fixed soliton separation of 4.7 ps, corresponding to the F-P cavity length of 700 μm. The single-shot spectra capturing technique reveals that the observed bound soliton is directly generated from continuous wave without experiencing single-soliton mode-locking process. The numerical results are in good agreement with the experimental observations and further confirm that the generation of bound solitons with locked separation is attributed to the F-P microcavity. The demonstration provides a versatile method to generate several types of separation-locked bound solitons by using F-P microcavity with diverse cavity lengths and reflectivities, which play vital roles in fiber sensor and optical information storage. ? 2022 Elsevier LtdAccession Number: 20220911731376 -
Record 418 of
Title:Thermal analysis method of optical scanning system drive shaft system
Author(s):Weining, Chen(1,2); Gong, Cheng(1); Sansan, Chang(2); Bo, Gao(2); Xiang, Li(2)Source: Journal of Physics: Conference Series Volume: 2295 Issue: 1 DOI: 10.1088/1742-6596/2295/1/012003 Published: 2022Abstract:In order to improve the heating problem of the rotating shaft components of the optical surveillance scanning system due to continuous operation, the feasibility of applying the oil-air lubrication technology to the drive shaft system of the optical surveillance scanning system was studied. Analyzed the contact load of the spindle bearing, obtained the calorific value of the heat source of the spindle component of the drive system, established the finite element analysis model of the temperature field of the spindle component, and calculated the thermal stability of the spindle component under the conditions of no lubrication and lubrication. Temperature rise. It is proposed to apply the oil-air lubrication method to the drive shaft system of the optical monitoring scanning system, and the corresponding lubrication parameters are calculated. ? Published under licence by IOP Publishing Ltd.Accession Number: 20223012391073 -
Record 419 of
Title:Optical design of three-line array airborne mapping camera with large field of view and high resolution
Author(s):Yan, Aqi(1); Dongsen(1); Zhang, Jian(1); Wu, Dengshan(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 12169 Issue: DOI: 10.1117/12.2620934 Published: 2022Abstract:In view of urgent demand high resolution and large field of view on three-line array airborne mapping camera, the paper proposes an airborne mapping camera optical system with large field of view and high resolution, which consists of single telecentric lens, RGB multispectral prism and field splicing prism. In order to solve RGB multispectral splitting problem in system, a new multispectral splitting prism based on a close distance confocal plane linear array sensor is proposed, which successfully solves RGB multispectral splitting problem of confocal plane linear array sensor with a close distance (B band and G band are only 4 pixels apart, and G band and R band are 2.2mm apart). The telecentric optical system is designed, focal length is 130mm, field of view (FOV) is 77°(working field of view is 60°), and image elecentricity is less than 0.1°across full field of view. There are four multispectral bands which are panchromatic?R?G?B band. The optical system has excellent imaging quality and compact structure. ? 2022 SPIEAccession Number: 20221611967502 -
Record 420 of
Title:Study on assembly process of flexible support mirror based on adhesive technology
Author(s):Wang, Peng(1); Kang, Shi-Fa(1); Zheng, Xiang-Ke(1); Geng, Bo(1); Wang, Wei(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 12166 Issue: DOI: 10.1117/12.2615620 Published: 2022Abstract:In the assembly of space camera, the assembly of large aperture mirror is the key of the system assembly. In this paper, the flexible supported mirror of space camera is taken as the research object, and a process route is proposed to complete the micro-stress assembly of the mirror and the transmission from optical datum to mechanical datum at one time by taking the adhesive assembly of the mirror and the transmission from optical datum to mechanical datum into consideration. According to this process route, the assembly process design and installation platform construction are completed. In addition, the factors affecting the micro-stress assembly of the mirror are analyzed theoretically and experimentally, and the transfer accuracy of the optical-mechanical reference is analyzed. This process method has been successfully applied to the assembly of a space camera's primary mirror. After the assembly, the shape of the primary mirror RMS is less than λ/50, and the Angle between the optical axis and the normal of the structure's mounting surface is less than 10". The process method presented in this paper provides a technical reference for the assembly of similar optical-mechanical systems. ? COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.Accession Number: 20220911734842