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Conference on Vertical-Cavity Surface-Emitting Lasers XVI (VCSELs)/SPIE Photonics West Symposium

作者： Seurin, Jean-Francois Xu, Guoyang Miglo, Alexander Wang, Qing Van Leeuwen, Robert Xiong, Yihan Zou, Wei-Xiong Li, daizong Wynn, James d. Khalfin, Viktor Ghosh, Chuni Princeton Optron Mercerville NJ 08619 USA

ISBN: (纸本)9780819489197

Vertical-cavity surface-emitting lasers (VCSELs) have emerged as a promising candidate for pumping of solid-state lasers, as they can be configured into high-power two-dimensional arrays and modules of arrays. VCSELs emit in a circular, uniform beam which can greatly reduce the complexity and cost of coupling optics. Their narrow and stable emission spectrum is well suited to the narrow absorption spectrum generally observed for solid-state gain media. The superior reliability of VCSELs greatly enhances the robustness of solid-state laser systems and enables high-temperature operation. In this work, we discuss recent developments on kW-class VCSEL pumps for solid-state lasers. Results on VCSEL modules designed for end-pumping and for side-pumping are presented. More than 4kW in CW operation is demonstrated from a multi-array VCSEL module. We also present results on solid-state lasers using VCSEL modules as pumps. In an end-pumping configuration, more than 250W peak power at 1064nm is demonstrated, and in a side-pumping Q-switched configuration, more than 21mJ at 946nm is demonstrated for an Nd:YAG solid-state laser.

关键词： Semiconductor laser solid-state laser vertical-cavity surface-emitting laser high power 2d array pumping Nd:YAG 808nm

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NANOPARTICLES SORTING ANd ASSEMBLY BASEd ON dOUBLE-AXICON IN AN OPTOFLUIdIC CHIP

NANOPARTICLES SORTING AND ASSEMBLY BASED ON DOUBLE-AXICON IN...

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27th IEEE International Conference on Micro Electro Mechanical Systems (MEMS)

作者： Shi, Y. Z. Xiong, S. Chin, L. K. Ren, M. Liu, A. Q. Xi An Jiao Tong Univ State Key Lab Mfg Syst Engn Xian 710049 Peoples R China Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore

ISBN: (纸本)9781479935086

This paper presents a novel optofluidic system for nanoparticle sorting by using interference patterns generated through a double-axicon. The tightly confined Bessel beam is used to sort the 200-nm and 500-nm polystyrene nanoparticles massively and simultaneously by adjusting the flow rate and the laser power. Additionally, 2-mu m polystyrene particles are assembled into a 2d array by utilizing the discrete interference pattern. This system first utilizes the interference patterns based on the on-chip double-axicon, and integrates the sorting and assembly abilities into a single chip. It has a great potential in bacterial and dNA sorting and cell assembly.

关键词： fluidic devices lenses light interference nanofabrication nanoparticles nanophotonics polymers 2d array assembly discrete interference pattern double axicon flow rate laser power optofluidic chip polystyrene nanoparticles size 2 mum size 200 nm size 500 nm sorting tightly confined Bessel beam Biomedical optical imaging Force Interference Laser beams Nanoparticles Optical scattering Sorting

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development of a 500 kHz pulse-echo acquisition system for three-dimensional ultrasound images of objects immersed in water 15

Development of a 500 kHz pulse-echo acquisition system for t...

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15th IEEE International Conference on Industry Applications, INdUSCON 2023

作者： Rodrigues, Estevão Patricio Buiochi, Flavio Departamento de Engenharia Mecatrônica e de Sistemas Mecânicos Universidade de São Paulo São Paulo Brazil

ISBN: (纸本)9798350314182

The development of an acquisition system that remotely captures echo signals to make three-dimensional ultrasound images of objects immersed in water is presented. The acquisition system is based on an STM32 microcontroller, which pulses a 500-kHz piezoceramic disc emitter, and so digitizes sixteen echo signals captured by two-dimensional array of sensors made of 1-3 piezocomposite. The digitized raw signals are transmitted to a personal computer (PC) via an Ethernet cable. The acquisition system was simplified by using the Power over Ethernet (PoE) technology, that integrates the power supply and data communication via the Ethernet cable itself. The beamforming is calculated on the PC, where the ultrasound images are displayed. Three-dimensional ultrasound images of objects immersed in water up to 1 meter away suggest that the proposed acquisition system can be improved for underwater purposes such as inspection of static underwater structures like bridges, pipeline occlusion and so on. ©2023 IEEE.

关键词： 2d array 3d Sonar Acquisition System Microcontroller Piezoelectric Ultrasound Ultrasound Imaging Underwater

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design Consideration for descanned Laminar Optical Tomography with EMCCd Camera 40

Design Consideration for Descanned Laminar Optical Tomograph...

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40th Annual Northeast Bioengineering Conference (NEBEC)

作者： Ozturk, Mehmet S. Intes, Xavier Yang, Fugang Rensselaer Polytech Inst Dept Biomed Engn Troy NY 12180 USA Shandong Inst Business & Technol Sch Informat & Elect Engn Yantai Peoples R China

ISBN: (纸本)9781479937288

Current Laminar Optical Tomography ( LOT) systems differ in their optical design, mainly in scanning mode strategies and detector selection. Herein, we investigate the design for an LOT system with an Electron Multiplying CCd camera in de-scanning mode. In de-scanning mode, the image of the detectors is scanned on the surface of the sample in conjunction with the raster scanned illumination spot. de-scanning 2d detector array yields high-density spatial sampling of the target with parallel data acquisition and high SNR. In this work, we investigate the effect of detector array configuration on the quality of reconstructions. Associated with l(p)-norm, due its better performance over conventional methods such as conjugate gradient or least square, 2d detector arrays provides high fidelity reconstructions with high-resolution.

关键词： tomography LP norm 2d array de-scanned

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Comparison of different optimized irregular sparse 2d ultrasound arrays

Comparison of different optimized irregular sparse 2D ultras...

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IEEE International Ultrasonics Symposium (IUS)

作者： diarra, Bakary Roux, Emmanuel Liebgott, Herve Ravi, Samikannu Robini, Marc Tortoli, Piero Cachard, Christian Botswana Int Univ Sci & Technol Elect Elect Comp & Telecommun Engn Dept Palapye Botswana Univ Lyon CREATIS Villeurbanne France CNRS UMR 5220 Villeurbanne France INSERM U1044 Villeurbanne France Univ Lyon 1 Villeurbanne France INSA Lyon Villeurbanne France Univ Florence Dept Informat Engn Florence Italy

ISBN: (纸本)9781467398978

The role of 2d matrix arrays in the realization of real time 3d ultrasound imaging is crucial as the latter permit to acquire a complete volume. The lack of control systems for these arrays containing thousands of elements and the dimension of connection cables for such a number of elements are the main obstacles to the use of these technologies. The sparse array techniques present a solid candidate to solve these technological limitations but give rise to beam pattern deteriorations in terms of energy loss and unwanted lobes apparition. The irregular positioning of the array elements permits to drastically decrease the unwanted lobes while the energy loss may be compensated by increasing the element size [1][2]. However, as elements get larger, the directivity decreases. To solve this directivity reduction, we propose to combine elements of different sizes in such a manner that a broad directivity is maintained using small elements whereas the energy loss may be compensated by wide ones. Additionally, an innovative simulated annealing based algorithm [3] is used to refine the array beam profile when the active element number is set to 256. The results compared to those obtained by the basic non-grid array show significant improvement in the beam pattern.

关键词： 2d array irregular sparse array 3d ultrasound imaging simulated annealing

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dynamic Correlation Function of Monodispersed Colloid

Dynamic Correlation Function of Monodispersed Colloid

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2nd International Conference on Mechanics and Control Engineering (ICMCE 2013)

作者： Promkotra, Sarunya Kandsadan, Tawiwan Khon Kaen Univ Fac Technol Dept Geotechnol Khon Kaen 40002 Thailand King Mongkuts Univ Technol N Bangkok KMUTNB Sirindhorn Int Thai German Grad Sch Engn TGGS Chenn & Proc Engn Program Dept Mech & Proc Engn Bangkok 10800 Thailand

ISBN: (纸本)9783037859087

diffusive behaviors for two-dimensional (2d) monodispersed polystyrene array of droplet spreading by either methanol or ethanol suspension are observed on a rigid surface. Methanol solution can spread speedily on the glass surface because of the positive spreading coefficient. Conversely, the ethanol will not easily proliferate out. Monodisperse polystyrene particles are involved in Brownian motion in a thick layer during alcohol evaporation. A monolayer dimension of the drop has been developed at the final spreading. Lateral capillary forces are produced and caused the aggregation of particles. Evaporation at the edge of the ethanol film did not lead to the film to retract. The formation of 2d array, which preceded the spreading of the microscopic droplet across the surface, is able to indicate the dense structure to the dynamic correlation function.

关键词： 2d array 2d aggregates spreading dynamics

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A dream for realization of high-speed, 3d volume image by lens-focused method

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International Congress Series 2004年第C期1274卷 38-46页

作者： Kaiho, Ieharu Shizuoka (411-0041) 1-25-13 Miharashidai Sano Mishima Japan

The technology of 3d volume image is progressing splendidly in the field of ultrasonic medical diagnosis in recent years. It will become still more important to understand the whole image of fatal part by 3d image. However, the volume updating time now requires several seconds for a one-volume scan, and still insufficient for monitoring true, real-time motion of the fatal part. A new technical innovation is required to realize this. The lens-focused method is described in this paper to realize the improvement in the volume updating speed. The author had been engaged in the development of imaging sonar and completed a sonar which used the lens-focused method last year. It succeeded in obtaining a 128×96 pixel frontal image by 15 frames/s of image updating speed in water. This paper shows that the lens system is able to be the key for high-speed, high-resolution and high-quality, 3d volume image. In order to apply this method to the field of medical diagnosis, a trial design of the lens system was performed. Consequently, it is shown that 1.2 mm resolution is obtained at 120 mm in front of the lens surface at a frequency of 5 MHz. The lens-focused method is desired to contribute to the realization of high-speed, 3d, real-time diagnostic equipment. © 2004, Elsevier B.V. All rights reserved.

关键词： 2d array 3d volume image Acoustical lens Lens-focused method Real time Speckle noise

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Optimal Parallel Searching an array for Certain Repetitions

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Electronic Notes in discrete Mathematics 2003年 12卷 82-93页

作者： Brimkov, Valentin E. Department of Mathematics and Computer Science SUNY Fredonia NY United States

Repetitive substructures of two-dimensional arrays have been recently defined and studied in an attempt to parallel some of the analogous developments already known for strings. In the present paper we propose an O (log log n) time O(n³ log n) work optimally fast, optimal parallel CRCW-PRAM algorithm for detecting all repetitions of certain type in an n × n array. © 2005 Elsevier Ltd. All rights reserved.

关键词： 2d array optimal parallel algorithm repetition tandem

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Uncooled microbolometer detector: recent developments at ULIS

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OPTO-ELECTRONICS REVIEW 2006年第1期14卷 25-32页

作者： Tissot, JL Trouilleau, C Fieque, B Crastes, A Legras, O ULIS F-38113 Veurey Voroize France

Uncooled infrared focal plane arrays are being developed for a wide range of thermal imaging applications. Fire-fighting, predictive maintenance, process control and thermography are a few of the industrial applications which could take benefit from uncooled infrared detector Therefore, to answer these markets, a 35-mu m pixel-pitch uncooled IR detector technology has been developed enabling high performance 160x120 and 384x4288 arrays production. Besides a wide-band version from uncooled 320x240\45 mu m array has been also developed in order to address process control and more precisely industrial furnaces control. The ULIS amorphous silicon technology is well adapted to manufacture low cost detector in mass production. After some brief microbolometer technological background, we present the characterization of 35 mu m pixel-pitch detector as well as the wide-band 320x240 infrared focal plane arrays with a pixel pitch of 45 mu m.

关键词： uncooled IRFPA 2d array MWIR LWIR microbolometer amorphous silicon

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Evaluating a single treatment planning beam model for multiple beam-matched linear accelerators

Evaluating a single treatment planning beam model for multip...

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作者： Liebner Koen University of the Free State

学位级别：硕士

The success of cancer treatment with radiation is highly dependent on the ability of the Treatment Planning System (TPS) to accurately calculate doses that would be delivered to the patient. The quality of TPS commissioning data, based on Linear Accelerator (Linac) measurements in water, largely determines the quality of the TPS beam model derived from this data. Modern treatment techniques such as Intensity Modulated Radiotherapy (IMRT) require highly accurate dosimetry equipment used for TPS commissioning. Once derived, the beam model should be verified with a range of tests other than commissioning procedures to test the beam model against Linac output. The study aims to investigate equivalences and differences between 5 Siemens Artiste TM Linacs of similar output, referred to as beam-matched Linacs, and how a single TPS beam model (Monaco TM ) can potentially be utilized for treatment planning for any of the Linacs. Generally, dosimeters used for TPS beam data collection differ largely from those used for post-modelling verification measurements. The study investigates the correlation between a high-resolution detector (microdiamond) typically used for collecting commissioning beam data and a post-modelling verification 2d array detector (Mapcheck2 TM ). Measurement resolution of Mapcheck2 TM was increased to 1 mm by repetition measurements, manually stepping the device in-between the detector-less spaces and software developed to convert data to a readable format. dose profiles from Mapcheck2 TM, with increased measurement resolution, and microdiamond agreed well. This method was further used to accurately determine Multi-leaf Collimator (MLC) errors from a range of MLC stop positions across the radiation field for each Linac respectively. This allowed for quantitative comparisons that showed significant differences between the MLCs of the 5 Linacs. A new radiological calibration curve (containing software MLC offset values) to reduce MLC errors were proposed f

关键词： 2d array diamond detector profiles spatial resolution beam-matching MLC error Treatment Planning System Intensity Modulated Radiation Therapy

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