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December 1, 2005 -- Optical Sciences Colloquium
-- 3:45 p.m. -- Meinel 408/410
Dr. Peter M. Rentzepis, Department of Chemistry and Electrical
& Computer Engineering at the University of California, Irvine, will
present Three Dimensional Optical Storage: Concept, Materials
and Systems. Abstract: The demand for ever larger storage
capacity for medicine, entertainment, defense and other applications
seems continuous to increase. Even with vertical bits and blue
lasers the limits "seems" to be in the hundreds of GB per disk. A
possible extension to volumetric, 3D, optical storage promises to supply
disks with several TB capacity. The concept of the volumetric
storage that is employed is based on non-linear two photon absorption and
accessing of the stored information by one or two photon processes.
The media used and the mechanism responsible for storing and accessing
information will be described and illustrated by several molecular media.
The storage media are molecules which are dispersed, uniformly, in
polymer matrices and fabricated into 1" or 3" diameter and 0.25" thick
optical quality disks. In such a 3D disk about 1000 micron size
planes are written with a total capacity of several Tbs. The
optical system used for write and read the information stored in 3D
format will be shown and discussed. (Professor Dror Sarid is the
OSC faculty host.)
November 17, 2005 -- Optical Sciences Colloquium -- 3:45 p.m. --
Meinel 408/410
Dr. Thomas D. Milster, University of Arizona Research Professor of Optical
Sciences and Electrical & Computer Engineering, will present Optics
Beyond the Diffraction Limit. Abstract: Many interesting
applications in optical data storage, lithography and microscopy require
efficient light confinement smaller than what is possible with conventional
optical systems and microscopes. This presentation discusses methods for
achieving such light confinement with optical transducers that utilize
evanescent energy. Evanescent energy decays rapidly away from the
transducer, similar to those evanescent waves produced by total internal
reflection, so the object being probed must be very close to the transducer.
Our experiments have demonstrated several interesting and useful properties
of the evanescent field.
November 10, 2005 -- Optical Sciences
Colloquium -- 3:45 p.m. -- Meinel 408/410
Dr. Harrison H. Barrett, Regents Professor of Radiology, Optical Sciences
and Applied Mathematics, will present New Approaches to Adaptive
Optics, Wavefront Sensing and 3D Microscopy. Abstract:
This colloquium will summarize recent results obtained by the speaker in
collaboration with the Applied Optics Group at National University of
Ireland, Galway. A comprehensive theory of image quality in adaptive
optics will be outlined, and applications to astronomical tasks such as
exoplanet detection and photometry in a crowded star field will be
discussed. The theory behind maximum-likelihood approaches to wavefront
sensing will be introduced, and preliminary results will be presented.
Some wavefront-sensing data that contradict a basic tenet of the
Kolmogorov theory of atmospheric turbulence will be presented and used as
a basis for a new method of atmospheric characterization. The use of
singular-value decomposition for three-dimensional image reconstruction
in through-focus scanning microscopy will also be described. OSC
Faculty Host: Professor Dror Sarid, 520-621-4603,
sarid@optics.arizona.edu
November 3, 2005 -- Optical Sciences Colloquium -- 3:45 p.m. -- Meinel
408/410
Dr. Kevin Thompson, OSC alumnus and Vice President of the Optical
Engineering Group at Optical Research Associates, will present A
Perspective on Early Optics: Based on Robert Smith (1738) and David Brewster
(1830). Abstract: For all practical purposes, the first
substantial book on optical design (over 800 pages), in English, was written
by Robert Smith in 1738. From this, it appears that optics, as we know it,
was effectively initiated by astronomers starting about 1650 with the work
of Mersenne and Gregory followed by Cassegrain and others. By the
mid-1850s, publications in optics were becoming widespread. In the 1820's,
one of the first encyclopedias ever compiled, the Edinburgh Encyclopedia,
was published. Conveniently for us, this was edited primarily by an opticist
- David Brewster, the inventor of the kaleidoscope and a researcher in
polarization. This encyclopedia provides an interesting and somewhat
complete perspective to the field of optics between Smith's book in 1738 and
1820 and actually extends back to 450 BC. To a great extent, it provides a
nearly complete picture of all of the developments in optics, relevant to
optical design, before the field exploded starting with, for example the
publication of Coddington's work in 1828. Also, with Kingslake’s book on
the history of photographic optics, which begins about 1810, these three
references combined provide a nearly complete view of the history of optical
deign. Some of the material in this talk can be found in the October issue
of Optics and Photonics News. As a one-time serious collector of books
in optics, but by no means a historian in optics, Kevin has had the
opportunity to acquire original copies of Smith's 1738 book (which is now
available in facsimile) and the entire edition of the 1820s Edinburgh
encyclopedia (which as you might expect is extremely rare in a complete set,
in the U.S.) as well a book by Gregory in the 1600s and many of the optics
books published in the 1800s (now resident at the University of Arizona,
Optical Sciences Center), including, for example, Coddington. This talk
will be an informal compilation of some of the more interesting information
that can be found primarily in the optics sections of the encyclopedia, but
also from Smith's book, and related books. Any historians in the audience
will be encouraged to add to the information. In addition, one or two
volumes of the encyclopedia and Smith's book will be available for those
interested.
October 27, 2005 -- Optical Sciences Colloquium -- 3:45 p.m. -- Meinel
408/410
Dr. James R. Biard, retired Chief Scientist at Honeywell Sensing &
Control, will present Light Emitters from LEDs to VCSELs.
Abstract: The relationship between GaAs solar cells, varactor diodes,
and tunnel diodes is discussed to show how the developing technology led to
the first GaAs light emitting diode (LED). The diode laser and the
relationship between research and engineering are also discussed in the
context of innovation. The talk reveals both successes and failures and how
they contributed to the development and application of LEDs. The emergence
and successful exploitation of any new technology requires that it be able
to pass three levels of feasibility: 1) conceptual feasibility, 2) technical
feasibility, and 3) economic feasibility. Many new ideas that meet the
first or first and second levels never make it past the third level of
feasibility. A good idea that is too far ahead of its time may not be
economically feasible because the infrastructure is not available to allow
it to be manufactured and applied at a reasonable cost and useful level of
reliability. Another factor that is absolutely required for economic
feasibility is an unfulfilled need that can be exploited by the emerging
technology. Many of the same factors that led up to the invention of
the LED are today impacting the emergence of the vertical cavity surface
emitting laser (VCSEL). Over the last several years the 850nm VCSEL has
become the light source of choice for use in short haul fiber optic data
communication. This new component would not have been possible without the
work of many engineers and scientists around the world who contributed to
the development of metal organic chemical vapor deposition (MOCVD), and
molecular beam epitaxy (MBE). These machines were developed to manufacture
GaAs integrated circuits, LEDs, and cleaved cavity lasers. However, they
are also capable of growing the complex material structures required by
VCSELs. Standards Committees have also played an important role in the
success of the VCSEL as an emerging new component. From the LED in
1961 to the VCSEL in 2001 covers a period that spans what has been a very
interesting and rewarding career in the ever emerging technology of
optoelectronic components.
October 21, 2005 -- Special Optical Sciences Colloquium -- Noon --
Meinel 408/410
Dr. Susan Houde-Walter, LaserMax, Inc. and a
College of Optical Sciences Adjunct Professor, will present Energy
Transfer Processes in Rare Earth Doped Materials. (Work done while
at the Institute of Optics, University of Rochester.) Abstract:
This talk will focus on glasses and glass-ceramics that serve as hosts to
dopants that impart desired optical properties (optical gain, especially).
We begin with a very brief discussion of structure-property relations and
some of the techniques that can be brought to bear in elucidating the short
and intermediate range molecular structure of multi-component glasses.
Water-related impurities can have a pronounced impact on the final optical
characteristics in rare-earth doped amplifier and laser glasses. Water is
difficult to remove from conventionally formed glasses, and vapor and flame
deposited glasses are severely limited in composition range. Glass-ceramics
provide an attractive alternative. In these materials, the optical and
chemo-mechanical properties can be segregated into glassy and nano-crystalline
phases. We present a study of upconversion fluorescence in oxyflouride
transparent glass-ceramics that have been doped with an erbium ion density
of 1.7 x 1020 cm-3. Time-gated fluorescence and excitation spectra as well
as photoluminescence decays are used to determine the nature and origin of
this fluorescence. We show that the energy transfer upconversion occurs in
the nano-crystalline phase and the sequential two-photon absorption
upconversion occurs in both glass and crystal phases. We further
demonstrate a new method to determine the fraction of erbium ions
partitioned into the nano-crystallite. Energy transfer microparameters of
the cross-relaxation and migration interactions are also determined.
Finally, we present a new method to determine the infrared-to-green energy
transfer upconversion parameter.
October 13, 2005 -- Optical Sciences Colloquium -- 3:45 p.m. -- Meinel
408/410
Julie Bentley of Corning Tropel Corporation and an Adjunct Professor at
the University of Rochester's Institute of Optics will present Color
Correction Challenges and Optical Design Solutions for DUV (Deep UltraViolet)
Microlithography Optics. Abstract: This talk will answer the
question "What makes designing a DUV color corrected optical system so
difficult?" DUV optical materials and their properties (transmission, index
of refraction, dispersion, etc.) will be discussed and contrasted with
standard visible optical materials. A variety of refractive, reflective,
and catiodioptric designs used in different microlithography applications
(printing, resist development, and inspection) will presented and compared.
In particular, the use of two and three surface multi-function components
for improved color correction will be highlighted.
gOctober 6, 2005 -- Optical Sciences Colloquium -- 3:45 p.m. -- Meinel
408/410
Dr. Barry H. Schechtman, Executive Director
Emeritus, Information Storage Industry Consortium, will present Technology Directions and Future Challenges in the Information Storage
Industry. Abstract: Recent directions in business,
society and technology have been converging to combine (a) an enormous rate
of creation of digital information and (b) a desire and/or requirement to
retain much of that information for long periods (decades). For the most
part, the needs of information system users are being well met by the
mainstream storage technologies: hard disk, tape and optical, which have
continued to make impressive progress and to offer users ever-improving
capacities and performance at continuously decreasing price. Current
storage products, driven by a high rate of innovation in both storage
devices and materials, are true poster children for leading edge
applications of nanotechnology. For example, we take for granted the
ability to store and retrieve billions of bytes of data (whether for
enterprise level, small business or personal reasons) at a cost per gigabyte
that is less than the price of a cup of coffee! Most users pay little or no
attention to the fact that storage products achieve such capabilities by
manufacturing devices with nanometer scale features to record and retrieve
nanometer scale marks at speeds approaching a billion operations per second.
A variety of developments have brought these technologies to their present
level. Although fundamental limits loom in the near future, a number of
imaginative approaches are being explored, both evolutionary and
revolutionary, to forestall the industry’s encounter with these “limits” or
to provide circumvention paths around them.
September 29, 2005 -- Optical Sciences Colloquium -- 3:45 p.m. --
Meinel 408/410
Dr. Pierre Meystre, University of Arizona Physics Department Head and
Professor of Physics and Optical Sciences, will present On the Move
... Abstract: This talk is about moving across campus, moving
the Physics Department to international prominence, and moving cold atoms
and molecules around.
September 22, 2005 -- Optical Sciences Colloquium -- 3:45 p.m. --
Meinel 408/410
Dr. Andrew Lowman, Group Supervisor at Jet Propulsion Laboratory and
candidate for the College of Optical Sciences faculty position of
Assistant/Associate Professor in the Optical Engineering Program, will
present Optical Engineering Challenges for the Terrestrial Planet Finder
Coronagraph. Abstract: NASA’s Terrestrial Planet Finder
Coronagraph (TPF-C), expected to launch late in the next decade, will detect
and characterize earth-like planets around nearby stars. The baseline TPF-C
design is an 8 meter, visible wavelength space telescope with a high
contrast starlight suppression instrument. An extrasolar planet is expected
to be 10 orders of magnitude fainter than its parent star. With an angular
separation as small as 4 lambda/D, diffracted light from the star will
exceed the planet signal by as many as 6 orders of magnitude. Achieving this
level of suppression requires extreme levels of wavefront correction and
stability. To demonstrate the viability of the mission, TPF-C has built the
High Contrast Imaging Testbed (HCIT), which combines advances in
high-density deformable mirrors, coronagraphic masks, and wavefront sensing
and control algorithms. Over the past two years, HCIT has demonstrated
unprecedented levels of performance: ~1E-9 contrast; and wavefront control
better than 1 Å. After describing the baseline TPF-C architecture, I will
present details of the HCIT design, experimental results, and some of the
optical engineering challenges faced for the testbed and mission.
September 15, 2005 -- Optical Sciences Colloquium -- 3:45 p.m. --
Meinel 408/410
Dr. R. John Koshel, Senior Staff Engineer at W/Lambda Research Corp. and
candidate for the College of Optical Sciences faculty position of
Assistant/Associate Professor in the Optical Engineering Program, will
present Illumination Optics: Its Story, Challenges, and Excitement.
Abstract: This talk gives an overview of the field of illumination
optics – its past, present, and future. Illumination optics is a relatively
new field that is solving a multitude of practical lighting problems and yet
the theoretical tools to handle illumination problems are still in their
infancy. I will discuss some key issues, in particular étendue, which is a
geometric quantity that expresses the transmission characteristics of an
optical system. In a lossless system, there is conservation of étendue,
which is often interchangeable with other terminology such as conservation
of radiance or brightness. There are several proofs for the conservation of
étendue, including the laws of thermodynamics, Liouville's Theorem in
statistical mechanics, and Stokes' Theorem applied to Hamiltonian systems.
The two most typical are the proofs of the conservation of radiance and the
conservation of generalized étendue. Étendue describes the concentration
and flux transfer efficiency capabilities of an optical system, while
playing a fundamental role in determining the desired distribution of light
at the target. These factors are quite important with the advent of new
source technology, such as LEDs, and the need to conserve energy while also
meeting lighting demands. The use of étendue plays a primary role in the
effective implementation of design optimization algorithms. Optimization of
illumination optics is far more complicated than standard lens optimization,
and it is one of the present-day challenges in the field. I will describe
in my presentation, nuances of the difficulty of illumination system
optimization; including sampling, object interference, parameterization, and
the merit function designation. I will also present a novel and refined
simplex method of optimization that can handle the inherent stochastic
process of ray-trace starved models. Some examples of modeled, toleranced,
and fabricated systems will be presented to highlight the results. Overall
the audience should expect to obtain an interesting overview of challenges
and excitement in the field of illumination optics.
September 8, 2005 -- Optical Sciences
Colloquium -- 3:45 p.m. -- Meinel 408/410
On September 8, Dr. Tomasz Tkaczyk, College of Optical Sciences Assistant
Research Professor and candidate for the College of Optical Sciences
faculty position of Assistant/Associate Professor in the Optical Engineering
Program, will present
Structuring
Light” - Potentials and Challenges of Structured Illumination/Projection
Techniques. Abstract:
Structured illumination/projection
(SIP) at its simplest involves the projection of a pattern onto an
object. In more advanced configurations, structured illumination is
a dynamic method in which the structure interacts with the spatial
frequencies of the object encoding information.
SIP techniques began their rapid growth together with development of array
detectors (CMOS, CCD) enabling simultaneous data acquisition for the
entire field of view. While the principles of SIP techniques are already
well developed for many applications (e.g. topography or displacements
measurement) it still has a tremendous potential. Widely available
faster detectors together with improved means of data analysis allowed
real time operation even if several images are required for data
reconstruction. The SIP was not only revived by new technologies (e.g.
MEMS, MOEMS) but also provided the basis for several inventions over the
last couple of years. The most pronounced examples are structured
illumination to achieve sectioning capabilities in classical microscopy
(Neil et al, 1997) or improving lateral resolution of the optical system
beyond the diffraction limit using Moiré technique (Gustafsson et
al, 2000). This colloquium presents the most important structured
illumination/projection features through comparison of specific
techniques and applications. The general SIP discussion including
techniques like: 3D measurements (topography/micro-topography),
experimental mechanics (strains, displacements), position interpolators,
computer graphics (education, animation, and art), and medical imaging
will be followed with more detailed examples. Full field heterodyne
interferometer for shape measurement (1), microscopy with structured
illumination (2) and computed tomography imaging spectrometer (CTIS) with
structured illumination (3) will be thoroughly described. The interesting
common element for all three techniques is the very high background
(several times larger than the signal) demanding new reconstruction
techniques and state of the art technologies. The presentation will
conclude with a discussion of the potentials given by these new
technologies and future research trends in structured
illumination/projection techniques.
September 1, 2005 -- Optical Sciences Colloquium -- 3:45 p.m. --
Meinel 408/410
Michael V. Paukshto, Ph.D., Stanford University, will launch the Optical
Sciences 2005-2006 Colloquium Series with Optical Testing of Nano-Films
for Next Generation LCD Displays. Abstract: This presentation provides
an overview of new polarization elements for the next generation LCD
displays. The LCD market has enjoyed a high growth rate for several years
and is projected to continue to grow by 21% per year over the next 5 years.
This growth is driving the development of new forms of polarizers and
retarders which are thinner and can be fabricated by low cost processes.
One important and labor-intensive step in LCD fabrication is attaching the
sheet polarizer to the cell. A way will be shown to replace this component
with in-cell coated polarizers. One potentially suitable coating
material under intensive study is new nano-thin crystalline film (TCF) based
on self-assembly in lyotropic liquid crystal dye solutions. These TCF have
been shown to function as a high efficiency retarders or as an E-mode
polarizer, a polarizer which absorbs one incident component as well as the
component normal to the film (z-component). E-mode polarizers have very
different field of view effects from sheet polarizers and thus provide new
solutions for the polarization aberration problems in LC displays. In-cell
TCF polarizer solves the parallax problem. It is 200-500 times thinner than
conventional sheet polarizer and has temperature stability up to 2500C.
Another problem of the current LCD design is high absorption losses. The
display transmittance is about 5-7% in white state without DBEF (Double
Brightness Enhancing Film, 3M) and up to 10-14% with DBEF. Using TCF
coatings the brightness can be increased up to 60%. TCF layers can be used
to produce multilayer interference reflective polarizer and polarization
interference color filters. Initial prototypes of these interference
elements will be discussed during the presentation. TCF applications
including compensating biaxial coatings, viewing angle enhancement coatings,
color correcting films, and coated polarizers are shown. Several types of
LCD with TCF coatings were recently made and tested by Philips, Sony, Quanta
Display, Samsung Electronics, and others. The results on simulations and
testing are presented.
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