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Conference on current developments in Lens design and optical engineering XV

作者： Zhao, Wei Wall, Christopher Maddikeri, Raghavendra May, Andy SABIC Innovat Plast LLC 1 Lexan Lane Mt Vernon IN 47620 USA SABIC Innovat Plast LLC Pittsfield MA 01201 USA

ISBN: (纸本)9781628412192

SABIC's ULTEM (TM) (polyetherimide) resin has been the choice of material for injection moldable micro lenses and lens arrays in optical communication components such as transceivers due to its unique combination of physical, thermal and optical properties including high refractive index, low absorption in near IR range, good dimensional stability and high heat performance. It's known that processing conditions affect properties of final parts. Often the processing conditions are optimized for best mechanical properties, while their effect on optical properties is sidelined. In this study, the effect of injection molding processing conditions on optical properties of polyetherimide resin is discussed.

关键词： Polyetherimide Injection Molding Processing Conditions optical Properties Lens

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Caustic surface of a plane wavefront refracted by a smooth arbitrary surface 15

Caustic surface of a plane wavefront refracted by a smooth a...

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Conference on current developments in Lens design and optical engineering XV

作者： Avendano-Aleja, Maximino Univ Nacl Autonoma Mexico Ctr Ciencias Aplicadas & Desarrollo Tecnol Mexico City 04510 DF Mexico

ISBN: (纸本)9781628412192

We study the formation of caustic produced by smooth arbitrary surfaces considering a plane wavefront propagating parallel to the optical axis and impinging on the refracting surface. We have already seen that the shape of the caustic surface can represent the monochromatic aberrations that we call image errors, furthermore the shape of the caustic can be modified by changing the parameters of the lens in such a way that if the caustic surfaces is vanished the optical system produces a perfect image, on the other hand for a caustic possessing a large area it could be applied to design no-imaging optical systems. The shape of the caustic depends only on the indices of refraction involved in the process of refraction, the refracting surface which is formed by smooth arbitrary plano-convex lens. We provide an analytic equation for the caustic surface after refraction of a plane wave from every rotationally symmetric surface.

关键词： Refraction Aspheric lenses Wavefronts Ray tracing optical design Geometrical optics Monochromatic aberrations Light Radon Wave propagation

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Analysis of double conjugate zoom lens using tunable-focus lenses 15

Analysis of double conjugate zoom lens using tunable-focus l...

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Conference on current developments in Lens design and optical engineering XV

作者： Novak, Jiri Novak, Pavel Miks, Antonin Czech Tech Univ Fac Civil Engn Dept Phys Prague 16629 6 Czech Republic

ISBN: (纸本)9781628412192

The work is focused on an analysis and modeling of paraxial imaging parameters of an optical system with a variable magnification or focal length, which keeps the position of object and image planes and entrance and exit pupil planes fixed. This system does not move its elements during the change of the magnification or the focal length. Such an effect can be achieved using tunable-focus active lenses. The described double conjugate zoom lens with tunable-focus lenses satisfies the requirement that object, image and pupil planes are fixed during the change of magnification or focal length. The system must be composed of at minimum three optical elements. Formulas are derived, which enable to determine focal lengths of individual elements of the optical system in a general case, when an object is situated in a finite or infinite distance from the optical system. Such an optical system can be principally used in the design of riflescopes with a variable magnification. This design of the riflescope has the advantage of the fixed position of its optical components (tunable-focus lenses). Further, the position of the exit pupil does not change and stays fixed in a fixed distance from the eyepiece during the change of magnification.

关键词： zoom lens tunable-focus lenses optical imaging first order optics riflescope

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Afocal viewport optics for underwater imaging 15

Afocal viewport optics for underwater imaging

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Conference on current developments in Lens design and optical engineering XV

作者： Slater, Dan 1352 Dorothea Rd La Habra Hts CA 90631 USA

ISBN: (纸本)9781628412192

A conventional camera can be adapted for underwater use by enclosing it in a sealed waterproof pressure housing with a viewport. The viewport, as an optical interface between water and air needs to consider both the camera and water optical characteristics while also providing a high pressure water seal. Limited hydrospace visibility drives a need for wide angle viewports. Practical optical interfaces between seawater and air vary from simple flat plate windows to complex water contact lenses. This paper first provides a brief overview of the physical and optical properties of the ocean environment along with suitable optical materials. This is followed by a discussion of the characteristics of various afocal underwater viewport types including flat windows, domes and the Ivanoff corrector lens, a derivative of a Galilean wide angle camera adapter. Several new and interesting optical designs derived from the Ivanoff corrector lens are presented including a pair of very compact afocal viewport lenses that are compatible with both in water and in air environments and an afocal underwater hyper-hemispherical fisheye lens.

关键词： Afocal lens design underwater photography water contact lens Ivanoff corrector lens dome port hyperhemispherical fisheye lens

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Materials design on the Origin of Gap States in a High-κ/GaAs Interface

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engineering 2015年第3期1卷 372-377页

作者： Weichao Wang Cheng Gong Ka Xiong Santosh K.C. Robert M.Wallace Kyeongjae Cho Department of Materials Science and Engineering The University of Texas at Dallas College of Electronic Information and Optical Engineering Nankai University

Given the demand for constantly scaling micro- electronic devices to ever smaller dimensions, a SiO2 gate dielectric was substituted with a higher dielectric-constant material, Hf（Zr）O2, in order to minimize current leakage through dielectric thin film. However, upon interfacing with high dielectric constant （high-κ） dielectrics, the electron mobility in the conventional Si channel degrades due to Coulomb scattering, surface-roughness scattering, remotephonon scattering, and dielectric-charge trapping.Ⅲ-Ⅴ and Ge are two promising candidates with superior mobility over Si. Nevertheless, Hf（Zr）O2/Ⅲ-Ⅴ（Ge） has much more complicated interface bonding than Si-based interfaces. Successful fabrication of a high-quality device critically depends on understanding and engineering the bonding configurations at Hf（Zr）O2/Ⅲ-Ⅴ（Ge） interfaces for the optimal design of device interfaces. Thus, an accurate atomic insight into the interface bonding and mechanism of interface gap states formation becomes essential. Here, we utilize first- principle calculations to investigate the interface between HfO2 and GaAs. Our study shows that As--As dimer bonding, Ga partial oxidation （between 3＋ and 1＋） and Ga- dangling bonds constitute the major contributions to gap states. These findings provide insightful guidance for optimum interface passivation.

关键词： high-mobility device high-κ/Ⅲ-Ⅴ interface interfacial gap states first-principle calculations

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Employment of fluorescence for autofocusing in direct laser writing micro-/nano-lithography 15

Employment of fluorescence for autofocusing in direct laser ...

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Conference on current developments in Lens design and optical engineering XV

作者： Malinauskas, Mangirdas Zukauskas, Albertas Belazaras, Kastytis Vilnius Univ Fac Phys Dept Quantum Elect Laser Res Ctr LT-10223 Vilnius Lithuania

ISBN: (纸本)9781628412192

Herein we present the implementation of autofocusing in multi-photon Direct Laser Writing (DLW) lithography. It is based on fluorescence occurring within the confined volume of a photopolymer/photoresin excitation resulting to a voxel generation. The proposed method is further successfully employed for the nanofabrication of large scale (500 nm in height, up to 25 mm(2) in area) Diffractive optical Elements (DOE). The produced structures are characterized using Scanning Electron Microscope (SEM) and confocal optical profilometry. The introduced technique is potential for a simple, price and effort efficient upgrade of currently existing DLW micro-/nano-lithography setups.

关键词： Direct laser writing femsosecond pulses two-photon polymerization multi-photon excitation nanolitography autofucusing photopolymers diffractive optical elements

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Using saddle points for challenging optical design tasks 15

Using saddle points for challenging optical design tasks

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Conference on current developments in Lens design and optical engineering XV

作者： Livshits, Irina Hou, Zhe van Grol, Pascal Shao, Yifeng van Turnhout, Maarten Urbach, Paul Bociort, Florian Natl Res Univ Informat Technol Mech & Opt 16 Birzhevaya Line St Petersburg 199034 Russia Delft Univ Technol Optic Res Grp NL-2628CJ Delft Netherlands TNO Sci & Ind NL-2628CK Delft Netherlands

ISBN: (纸本)9781628412192

The present research is part of an effort to develop tools that make the lens design process more systematic. In typical optical design tasks, the presence of many local minima in the optical merit function landscape makes design non-trivial. With the method of Saddle Point Construction (SPC) which was developed recently ([F. Bociort and M. van Turnhout, Opt. engineering 48, 063001 (2009)]) new local minima are obtained efficiently from known ones by adding and removing lenses in a systematic way. To illustrate how SPC and special properties of the lens design landscape can be used, we will present the step-by-step design of a wide-angle pinhole lens and the automatic design of a 9-lens system which, after further development with traditional techniques, is capable of good performance. We also give an example that shows how to visualize the saddle point that can be constructed at any surface of any design of an imaging system that is a local minimum.

关键词： saddle points wide-angle lens

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optical performance analysis of plenoptic camera systems 15

Optical performance analysis of plenoptic camera systems

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Conference on current developments in Lens design and optical engineering XV

作者： Langguth, Christin Oberdoerster, Alexander Brueckner, Andreas Wippermann, Frank Braeuer, Andreas Fraunhofer Inst Appl Opt & Precis Engn D-07745 Jena Germany

ISBN: (纸本)9781628412192

Adding an array of microlenses in front of the sensor transforms the capabilities of a conventional camera to capture both spatial and angular information within a single shot. This plenoptic camera is capable of obtaining depth information and providing it for a multitude of applications, e.g. artificial re-focusing of photographs. Without the need of active illumination it represents a compact and fast optical 3D acquisition technique with reduced effort in system alignment. Since the extent of the aperture limits the range of detected angles, the observed parallax is reduced compared to common stereo imaging systems, which results in a decreased depth resolution. Besides, the gain of angular information implies a degraded spatial resolution. This trade-off requires a careful choice of the optical system parameters. We present a comprehensive assessment of possible degrees of freedom in the design of plenoptic systems. Utilizing a custom-built simulation tool, the optical performance is quantified with respect to particular starting conditions. Furthermore, a plenoptic camera prototype is demonstrated in order to verify the predicted optical characteristics.

关键词： plenoptic camera depth of field depth resolution optical performance analysis customized microlens array

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"Moth's eye" anti-reflection gratings on germanium freeform surfaces 15

"Moth's eye" anti-reflection gratings on germanium freeform ...

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Conference on current developments in Lens design and optical engineering XV

作者： Liu, Meng Shultz, Jason A. Owen, Joseph D. Davies, Matthew A. Suleski, Thomas J. Univ N Carolina Ctr Optoelect & Opt Commun Charlotte NC 28223 USA Univ N Carolina Ctr Precis Metrol Charlotte NC 28223 USA

ISBN: (纸本)9781628412192

Germanium is commonly used for optical components in the infrared, but the high refractive index of germanium causes significant losses due to Fresnel reflections. Anti-reflection (AR) surfaces based on subwavelength "moth's eye" gratings provide one means to significantly increase optical transmission. As found in nature, these gratings are conformal to the curved surfaces of lenslets in the eye of the moth. Engineered optical systems inspired by biological examples offer possibilities for increased performance and system miniaturization, but also introduce significant challenges to both design and fabrication. In this paper, we consider the design and fabrication of conformal moth's eye AR structures on germanium freeform optical surfaces, including lens arrays and Alvarez lenses. Fabrication approaches and limitations based on both lithography and multi-axis diamond machining are considered. Rigorous simulations of grating performance and approaches for simulation of conformal, multi-scale optical systems are discussed.

关键词： biomimetic optics freeform surfaces conformal optics moth's eye gratings infrared optical modeling diamond machining interference lithography

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Multi-aperture microoptical system for close-up imaging 15

Multi-aperture microoptical system for close-up imaging

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Conference on current developments in Lens design and optical engineering XV

作者： Berlich, Rene Brueckner, Andreas Leitel, Robert Oberdoerster, Alexander Wippermann, Frank Braeuer, Andreas Fraunhofer Inst Appl Opt & Precis Engn D-07745 Jena Germany

ISBN: (纸本)9781628412192

Modern applications in biomedical imaging, machine vision and security engineering require close-up optical systems with high resolution. Combined with the need for miniaturization and fast image acquisition of extended object fields, the design and fabrication of respective devices is extremely challenging. Standard commercial imaging solutions rely on bulky setups or depend on scanning techniques in order to meet the stringent requirements. Recently, our group has proposed a novel, multi-aperture approach based on parallel image transfer in order to overcome these constraints. It exploits state of the art microoptical manufacturing techniques on wafer level in order to create a compact, cost-effective system with a large field of view. However, initial prototypes have so far been subject to various limitations regarding their manufacturing, reliability and applicability. In this work, we demonstrate the optical design and fabrication of an advanced system, which overcomes these restrictions. In particular, a revised optical design facilitates a more efficient and economical fabrication process and inherently improves system reliability. An additional customized front side illumination module provides homogeneous white light illumination over the entire field of view while maintaining a high degree of compactness. Moreover, the complete imaging assembly is mounted on a positioning system. In combination with an extended working range, this allows for adjustment of the system's focus location. The final optical design is capable of capturing an object field of 36x24 mm(2) with a resolution of 150 cycles/mm. Finally, we present experimental results of the respective prototype that demonstrate its enhanced capabilities.

关键词： Multi-aperture imaging microoptics multi-channel optical design image sensors

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