Published by De Gruyter

Volume 2 Issue 4

Issue of Advanced Optical Technologies

Contents
Journal Overview

Masthead

Publicly Available August 3, 2013

Community

Publicly Available August 3, 2013

Interview with Jyrki Saarinen, the new Executive Director of EOS

Jyrki Saarinen

Page range: 277-279

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Publicly Available August 3, 2013

Conference Notes

Page range: 281-283

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Publicly Available July 16, 2013

Topical Issue: Lighting technology

Editorial

Publicly Available August 3, 2013

Lighting technology

Roland Lachmayer, Juan C. Miñano

Page range: 289-289

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Tutorial

Publicly Available August 3, 2013

Extracting light out of LEDs

Julius Muschaweck, Christopher Wiesmann

Page range: 291-300

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Abstract

‘External quantum efficiency’, that is, the number of photons generated per electron passing through the p-n junction of an LED is probably the most important number to quantify the performance of an LED chip. Although advances in epitaxy have increased the fraction of radiative recombination to extremely high values, the extraction of the precious photons that are trapped in a high refractive index crystal is still tricky. In this brief tutorial, we look at the physics of light extraction both from a geometrical optics/thermodynamic and a wave optics point of view, discussing both random and deterministic surface structures.

Review Articles

August 3, 2013

Light shaping for illumination

Rolf Wester, Axel Bäuerle

Page range: 301-311

Abstract

The ever-increasing use of LED as a solid-state light source in general and specialized lighting has pushed the field of optics further for illumination towards sophistication and high precision. In this paper, we provide an overview of this domain, starting with a formulation of the underlying, fundamental mathematical problem, which in itself is not easily and directly solvable. We then describe various algorithms that have been developed as approximations for specialized cases, providing references to the relevant publications. Finally, two examples show the new possibilities in light shaping that have been made possible through the use of nonimaging freeform optics.

Publicly Available August 3, 2013

Lighting with laser diodes

Chandrajit Basu, Merve Meinhardt-Wollweber, Bernhard Roth

Page range: 313-321

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Abstract

Contemporary white light-emitting diodes (LEDs) are much more efficient than compact fluorescent lamps and hence are rapidly capturing the market for general illumination. LEDs are also replacing halogen lamps or even newer xenon based lamps in automotive headlamps. Because laser diodes are inherently much brighter and often more efficient than corresponding LEDs, there is great research interest in developing laser diode based illumination systems. Operating at higher current densities and with smaller form factors, laser diodes may outperform LEDs in the future. This article reviews the possibilities and challenges in the integration of visible laser diodes in future illumination systems.

Research Articles

August 3, 2013

SMS freeforms for illumination

Pablo Benitez, Juan C. Miñano, Julio Chaves, Asunción Santamaría

Page range: 323-329

Abstract

SMS 3D (simultaneous multiple surfaces in their three-dimensional version) is a well-known design method comprising two freeform surfaces that allow the perfect coupling of two wavefronts with another two. The design algorithm provides a collection of line pairs on both surfaces (called SMS spines), whose three-dimensional shape seems arbitrary at first sight. This paper shows that the shapes of the spines are partially governed by applying the étendue conservation theorem to the biparametric bundle of rays linking the paired spines, which is one lesser known étendue invariants found by Poincaré. The resulting formulae for the spines in three-dimensional space happen to coincide with the conventional étendue formulas of two-dimensional geometry, like for instance, the Hottel formula.

August 3, 2013

Backlight illumination design using constant extinction

Jörg Baumgart

Page range: 331-336

Abstract

Light guiding backlights are a good solution to attain ambient or display illuminations. Generally, they are attained using intended macroscopic defects (dots). Their size, shape and density are designed using ray tracing software. Smaller defects have the fascinating feature that they may not be perceived by the eye. Such a light guide will therefore look transparent and undisturbed. However, such microscopic or even nanoscaled defects are well beyond the limitations of geometrical optics and therefore need other approaches for their design. An interesting alternative to surface defects are particles inside the material or a well-defined surface roughness. In contrast to a defect structure, particle densities or surface roughness cannot be changed without difficulty. These may, however, be much more easily manufactured. In this paper, a simple analytical method for the design of such light guides will be presented. This method is compared to the results of commercial software and will be used to design a homogeneous illumination adopting constant particle density inside the material.

Review Article

July 23, 2013

Deconvolution for digital in-line holographic microscopy

Brenden Scott Nickerson, Hans Jürgen Kreuzer

Page range: 337-344

Abstract

To improve the resolution in point source digital in-line holography, we present two deconvolutions, one for the illumination system (coherent or partially coherent light source such as a laser or diode and pinhole) and one for the finite numerical aperture of the hologram. We show that for a system with moderate numerical aperture, optimal resolution of λ /2 laterally and λ in depth can be achieved.

About this journal

Objective

Advanced Optical Technologies is a strictly peer-reviewed scientific journal. The major aim of Advanced Optical Technologies is to publish recent progress in the fields of optical design, optical engineering, and optical manufacturing. Advanced Optical Technologies has a main focus on applied research and addresses scientists as well as experts in industrial research and development.

Advanced Optical Technologies partners with the European Optical Society (EOS). All its 4.500+ members have free online access to the journal through their EOS member account.

Topics

Optical design
Lithography
Opto-mechanical engineering
Illumination and lighting technology
Precision fabrication
Image sensor devices
Optical materials (polymer based, inorganic, crystalline/amorphous)
Optical instruments in life science (biology, medicine, laboratories)
Optical metrology
Optics in aerospace/defense
Simulation, interdisciplinary
Optics for astronomy
Standards
Consumer optics
Optical coatings

Article formats
Tutorial, Review Article, Research Article, Letter, Short Communication, Views

> Information on submission process

Volume 2 Issue 4

Issue of Advanced Optical Technologies

Masthead

Interview with Jyrki Saarinen, the new Executive Director of EOS

Conference Notes

Conference Calendar

Lighting technology

Extracting light out of LEDs

Abstract

Light shaping for illumination

Abstract

Lighting with laser diodes

Abstract

SMS freeforms for illumination

Abstract

Backlight illumination design using constant extinction

Abstract

Deconvolution for digital in-line holographic microscopy

Abstract