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Limits on the performance of RF-over-fiber links and their impact on device design

IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES 2006年第2期54卷 906-920页

作者： Cox, CH Ackerman, EI Betts, GE Prince, JL Photon Syst Inc Billerica MA 01821 USA

This paper is divided into two major parts. Following a brief introduction that establishes some definitions and assumptions, Section ii updates our earlier study on the limits of the RF performance of optical links. Section iiI reviews progress since our 1997 review paper in the development of devices enabling link performance closer to these limits, including (but not limited to): 1) cascade lasers that permit broad-band direct modulation links with gain > 0 dB;2) injection-locked edge- and surface-emitting lasers at 1300 and 1550 run with modulation frequency responses as great as 40 GHz;3) modulators with improved performance, especially electroabsorption modulators that now have switching voltages as low as 0.36 V, or handle optical powers as great as 60 mW, or have bandwidths as great as 50 GHz (but not all three of these in one device yet);and 4) high-speed photodetectors with high saturation currents, e.g., a 20-GHz device with a saturation current of 90 mA and a 55-GHz device with saturation at 50 mA. We conclude in Section IV by summarizing the component developments necessary for higher performance RF-over-fiber links, i.e.: 1) semiconductor lasers (for direct modulation) that have higher slope efficiency and bandwidth and lower relative intensity noise (RIN) at reasonable bias current levels;2) continuous wave (CW) lasers (for external modulation) with higher fiber-coupled power and lower RIN;3) higher frequency lower loss external modulators with more linear transfer functions and lower V, that can withstand larger CW optical powers;and 4) photodetectors with higher responsivity and bandwidth that respond linearly even when illuminated by greater average optical powers.

关键词： future development microwave photonics reviews technological forecasting

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An optimized design of a scanning confocal probe

An optimized design of a scanning confocal probe

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Conference on current developments in Lens design and optical engineering Vii

作者： Qiu, Z. R. Qin, J. Zhang, H. W. Zhang, G. X. Lu, Stephen C. Tianjin Univ State Key Lab Precis Measuring Technol & Instrume Tianjin 300072 Peoples R China Univ Southern Calif Dept Aerosp & Mech Engn Los Angeles CA 90089 USA

ISBN: (纸本)0819463671

Basing on the principle of dynamic active confocal measuring method, a non-contact probe was introduced. The relation between the displacement of the object measured and the displacement of the oscillating unit was established by applying to the measure principle. To find the effect way to improve the output signal, a mathematical modal of the photoelectric signal was proposed. According to the mathematical modal, the diameter of the pinhole was decided and the optical path was adjusted, which improved the performance of the probe. It valuable to emphasize that the double lens oscillating unit was the crucial parts of the mechanical and optical structure. The tuning fork stimulating, inductive coils and the pinhole and photodiode adjuster device were designed according to the theoretical analysis, which were more convenient to the measure task. The stability of the oscillating unit was tested;and the optical and mechanical performance of the probe was validated by experiments using gage blocks combining with a micro-motion measuring mount model. The cost of a micro-displacement testing sensor was saved in designing of this kind of probe. A more accurate signal processing method was discussed in this paper.

关键词： dynamic active confocal mathematical modal structure stability

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Self-weight distortion of lens elements

Self-weight distortion of lens elements

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Conference on current developments in Lens design and optical engineering Vii

作者： DeWitt, Frank Nadorff, Georg Naradikian, Markar Melles Griot Opt Grp 55 Sci Pkwy Rochester NY 14620 USA

ISBN: (纸本)0819463671

Changes in the shape of large lens elements due to the influences of gravity are important to consider in the fabrication, testing and assembly of optical systems. Tried and proven methods used for mounting large mirrors to minimize the effects of gravity are typically not applicable to large transmissive lens elements, due to the simple requirement that the clear aperture of a lens must remain free of mechanical obstructions. Precautions must be taken to ensure that an element's surfaces are correctly fabricated and then maintained when assembled into the final system. The amount of distortion caused by the weight of a particular lens element is dependent on a number of factors including: size, aspect ratio, shape, material, and the support on which it rests. Examples of the effects of these factors are modeled using Finite Element Analysis and demonstrated through interferometric testing. Attention is given to the mounting of lens elements within a system and simulating "real-world" conditions. These "real-world" conditions can produce results that are different from what was expected if only ideal cases have been considered. The work presented will aid the designer, fabricator, and metrologist to identify what optical elements and mounting conditions may be problematic and to minimize their effects.

关键词： optomechanical finite element analysis self-weight distortion gravity sag optical mounting tolmncing surface irregularity

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optical design for the Adaptive Secondary Setup and Instrument Stimulator (ASSIST)

Optical design for the Adaptive Secondary Setup and Instrume...

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Conference on current developments in Lens design and optical engineering Vii

作者： Hallibert, Pascal Arsenault, Robin Delabre, Bernard Esposito, Simone Hubin, Norbert Quirrenbach, Andreas Riccardi, Armando Stroebele, Stefan Stuik, Remko Vink, Ramon Leiden Observ POB 9513 NL-2300 RA Leiden Netherlands ESO DE-85748 Garching Germany Osserv Astrofis Arcetri I-50125 Florence Italy

ISBN: (纸本)0819463671

A comprehensive suite of Adaptive Optics systems and AO-assisted instruments is currently under development for the VLT and will be built around a hyperbolic convex adaptive Deformable Secondary Mirror (DSM). In telescopes with such a secondary mirror, test and calibration of both the DSM and the science instruments using it are notoriously expensive and time-consuming. The Adaptive Secondary Setup and Instrument Stimulator (ASSIST) is being developed to allow test and integration of three key elements of the future VILT Adaptive Telescope Facility: the DSM and 2 instrument-specific adaptive optics systems (GALACSI for MUSE and GRAAL for HAWK-I). The core of ASSIST is a standalone interferometric test setup for the DSM allowing its test at its center of curvature (significantly reducing the size of the classical hyperbole focii test configuration). This setup is completed by a star simulator for both natural and laser guide stars, a turbulence generator (for realistic AO performance measurements), a corrector system generating a VLT-like exit pupil and a Nasmyth rotator simulator interfacing with the two AO systems. In this paper we present the optical architecture of ASSIST, detailing the current design of the different parts of the system, and discuss its projected performance and compliance with the test and calibration requirements.

关键词： Adaptive Optics Deformable Secondary Mirror ASSIST Test Bench Pupil Imaging Turbulence Generator VLT Adaptive Optics Facility GALACSI GRAAL MUSE HAWK-I

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Analysis and design of an adaptive lens

Analysis and design of an adaptive lens

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Conference on current developments in Lens design and optical engineering Vii

作者： Santiago-Alvarado, A. Vazquez-Montiel, S. Gonzalez-Garcia, J. Garcia-Luna, V. M. Fernandez-Morena, A. Vera-Diaz, E. UTM Inst Fis & Matemat Huajuapan Leon Oaxaca 6900 Mexico INAOE Inst Opt Puebla Mexico

ISBN: (纸本)0819463671

This study presents the design and analysis of a lens with a variable focal length, which we will call an adaptive lens. This lens is formed of two transparent elastic surfaces with a transparent liquid medium between them. The mechanical design of the lens considers the variation of liquid pressure between the surfaces. This causes changes in curvature radii and in the axial thickness, generating variations in the focal length of the lens. An analysis is given of changes in lens power with respect to changes in pressure. Finally, a model of the human eye is presented using this adaptive lens as crystalline.

关键词： adaptive elastic surfaces liquid lens model human eyes

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Low profile optic design for mobile camera using dual freeform reflective lenses

Low profile optic design for mobile camera using dual freefo...

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Conference on current developments in Lens design and optical engineering Vii

作者： Jeong, Ho-Seop Yoo, Ho-Sik Lee, Sang-Hyuk Oh, Hae-Ran Samsung Elect Mech Cent R&D Inst Opt Lab Suwon 443743 South Korea

ISBN: (纸本)0819463671

Aspherical glass or plastic lenses are usually adapted in the camera module of handheld phone. Recently, slimmer cameras are required according to reducing thickness of handheld phone. In this paper, we present an ultra slim camera module using multiple freeform off-axis imaging lenses. New optical concept of multiple lens system introduces the planar optics with freeform. shaped aspherical lens surface on the wafer, which can achieve the thickness of 50% compared to the conventional symmetric lens system. In order to achieve the resolution specification, we separate the field of view in camera module. As the result, two inverted images are produced on a same imaging sensor and the acquired inverted images are processed by photo stitching algorithm so as to combine them. Finally, in order to verify the new imaging system, we manufacture the new slim lens through the LJV embossing replication process. We found the new imaging system is feasible for VGA resolution and it can be expandable to the high resolution system.

关键词： freeform. surface planar integrated optics photo stitching wafer scale lens UV embossing

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Photonics: design, Technology, and Packaging ii

Photonics: Design, Technology, and Packaging II

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Photonics: design, Technology, and Packaging ii

ISBN: (纸本)0819460699

The proceedings contain 57 papers. The topics discussed include: atomic motion and density fluctuations in cavity QED with atomic beams;a photonic quantum gate based on electronically controlled strong cavity coupling between a single nanocrystal quantum dot and an ultra-high-Q silica micro-cavity;optical microrheology of biopolymers;towards crystallization using optical tweezers;recent developments of quantum detectors in the tetrahertz range;simulation of tetrahertz radiation in stratified media;nonlinear photonic crystals in chalcogenide films;dynamic optical comb filter using opto- VLSI processing;polarized-light optical actuation in chalcogenide glasses: macroscopic model;and photonics of silicon nanocrystals.

关键词： optical engineering

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Novel technique for measurement of centration errors of complex, completely mounted multi--element objective lenses

Novel technique for measurement of centration errors of comp...

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Conference on current developments in Lens design and optical engineering Vii

作者： Heinisch, J. Dumitrescu, E. Krey, S. Triopt GmbH Hafenstr 39 D-22880 Wedel Germany

ISBN: (纸本)0819463671

The size and the focal length of camera objectives (e.g. cell phones or digital cameras) are becoming smaller and smaller. At the same time the quality requirements are increasing. Besides surface accuracy, the imaging quality of the complete optics is mainly influenced by the alignment errors of the single elements. TRIOPTICS has developed a new technology called MultiLens((R)) in order to measure the centering errors of all single surfaces within an objective lens with up to 40 surfaces or more. We achieve accuracies in the range of an arc second. During the measurement the deviation of each center or curvature with respect to a reference axis is measured. These data are further processed in order to provide the shift and tilt of an individual lens or group of lenses in respect to a given reference axis (Patent pending Ref. 1). Applications mainly include the measurement of cell phone and digital camera lenses. However, any type of objective lens from endoscope up to very complex objective lenses used in microlithography can be measured with highest accuracy. The method has been extended to measure also the aspherical axis of lenses.

关键词： centering centration lens optical surface objective aspherical axis digital camera cell phone camera tilt shift

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current progress of active pixel sensor developments for future the European Space Agency planetary and sun observation missions

Current progress of active pixel sensor developments for fut...

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Conference on High Energy, optical, and Infrared Detectors for Astronomy ii

作者： Duvet, L. Martin, D. D. E. Owens, A. European Space Agcy Estec Sci Payload & Adv Concept Off Keplerlaan 1 NL-2200 AG Noordwijk Netherlands

ISBN: (纸本)0819463418

Active Pixel Sensors (SWIR, optical and UV/EUV) have been identified by ESA (European Space Agency) as remote sensing payload detector technology for the next two major science missions: Bepi Colombo and Solar Orbiter. The Bepi Colombo probes will be launched in 2013 toward Mercury in cooperation with the Japanese Space Agency. The Solar Orbiter spacecraft will be launched in 2015 and will study the sun as close as 45 sun radii. Due to their improved electro-optical characteristics, reduced power consumption and more important their potential radiation hardness, Active Pixel Sensors are a priori ideal candidates for such challenging missions. To fulfill the scientific requirements while meeting the stringent mission constraints, dedicated activities have been initiated in the European industry under ESA funding: design and manufacture of a 2kx2k, 10 um pitch optical array, a 512x256 30 um optical-SWIR array and technological developments for EUV Solar blind arrays. To support these activities, SCI-AI has developed in house expertise and testing capabilities in its labs so far focused on higher energy detectors (X, gammas). A particular effort is being brought to develop knowledge and hands-on experience on radiation testing of APS. We will report in a first section the early trade-offs of the above mentioned industrial developments. We will then present in more details preliminary radiation test results obtained on the STAR1000 Active Pixel Sensor, one of the most interesting precursor of the future generation of APS for space in Europe.

关键词： Active Pixel Sensor CCD Bepi Colombo Solar orbiter radiation hard STAR1000

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design of miniaturized optoelectronic systems using resonant micro scanning mirrors for projection of full-color images

Design of miniaturized optoelectronic systems using resonant...

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Conference on current developments in Lens design and optical engineering Vii

作者： Scholles, M. Braeuer, A. Frommhagen, K. Gerwig, Ch. Hoefer, B. Lakner, H. Schenk, H. Schwarzenberg, M. Fraunhofer Inst Photon Microsyst Maria Reiche Str 2 D-01109 Dresden Germany Fraunhofer Inst Appl Opt & Precis Engn D-07745 Jena Germany

ISBN: (纸本)0819463671

Projection systems comprising micromechanical. scanning mirrors are a promising approach for information display of any kind. If combined with advanced laser diodes as light sources, ultra-compact projection heads can be realized, as it will be shown in this contribution. Besides the laser, key component of the system is a special MEMS device, a two-dimensional resonant micro scanning mirror. The laser beam formed by collimator optics is directed onto the micro scanning mirror. Then, the reflected beam describes a highly complicated Lissajous figure on the projection screen with flare angles of up to 20 degrees. By driving the mirror and electrically modulating the intensity of the laser beam in a synchronous manner, projection of images can be achieved. Advanced techniques that guarantee improved image quality and allow compensation of artifacts because of relative movement between projection head, screen, and human observer will be described. Based on these principles, several optoelectronic systems have been designed. A monochrome projection head that incorporates the laser diode, optics and the micro mirror could be reduced to a volume of 15mm x 7 mm x 5mm. A slightly larger head is attached to a laser unit with red, green, and blue lasers via glass optical fiber for projection of full color images and video streams. All systems have VGA (640 x 480 pixels) resolution. They operate with 8 bit color depth per pixel and 50 frames per second. These key features in combination with the miniaturized size allow their use for a broad range of applications.

关键词： image projection scanning mirror MEMS resonant scanning micro optics

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