3D
reconstruction from a single hologram of yeast cells recorded by the
holographic microscope. 3D information is calculated from
the phase image.
HOLOGRAPHIC
ENDOSCOPE DEVELOPMENT
3D reconstruction from a single hologram recorded by the holographic endoscope. Here a stereo view is obtained
from a single hologram and disparity map is calculated. Then the 3D depth map is combined with the actual 2D image.
STATIC FOURIER TRANSFORM SPECTROMETER WITH BAND PASS SAMPLING...
A unique hybrid optical spectrometer. Here we take advantage of band pass sampling theorem to get away with the Nyquist sampling
rate limitations...
THZ
WAVE DETECTION WITH RECTENNAS
Before
2012 ...
3D
HOLOGRAPHIC IMAGING
This
is one of my latest projects. Currently we are investigating 3D imaging
of objects in transmissive or
reflective configuration. Holograms are recorded on a CCD camera and
the image is
created on the computer.
Various signal processing algorithms for increasing the image
quality are explored as well as the
transformation
methods to visualize the objects in 3D.
Two
important applications we are considering are:
3D imaging of tissues that we call "holographic optical coherence
tomography", and imaging of vibrating objects
coupled with a microphone array for
locating the sound source.
Here is some of the publications
related to this work:
“Method to calculate the far field
of three-dimensional objects for computer-generated holography”, Muharrem
Bayraktar and Meriç Özcan
Appl.
Opt., Vol. 49, Issue 24, pp. 4647-4654 (2010)
“Holographic
recording without a separate reference wave”, Meriç
Özcan
andMuharrem
Bayraktar Proc.
SPIE 7619 76190K (2010)
“Digital
holography image reconstruction methods”, Meriç
Özcan and
Muharrem Bayraktar Proc.
SPIE 7233
72330B (2009)
"A new method for computer generated
holography of 3D objects", Muharrem
Bayraktar andMeriç
Özcan, 24th
International Symposium on Computer and Information Sciences, 2009
(ISCIS 2009), IEEE
(Institute of Electrical and Electronics Engineers), Sep. 2009, 66-69
"A
method for generating artificial holograms",
Muharrem
Bayraktar and
Meriç
Özcan 4th
European Optical Society Topical Meeting on Advanced Imaging
Techniques, Jena,
Germany, June 2009.
“Structural
and acoustic optimization of door modulus for radiated noise
levels”,
Emre
Armağan,
Meriç
Özcan,Serhat
Yeşilyurt, andGökhan
Göktuğ InterNoise07
209
4044 (2007) "Hilbert
dönüşümü tabanlı hologram filtreleme", Muharrrem
Bayraktar and Meriç Özcan, SIU
2010, Diyarbakır, Nisan 2010.
"Holografik
interferometri kullanarak yüzey sapmalarının incelenmesi", Muharrrem
Bayraktar and Meriç Özcan, ELECO'08,
Bursa, 26-30 Kasım, 2008. MATTER
WAVE INTERFEROMETRY...
HOW TO MAKE BETTER ATOMIC GYROSCOPES...
Sagnac
effect is a rotationally induced phase shift between two paths of an
interferometer. Gyroscopes based
on this effect measure a rotation rate relative to an inertial frame of
reference. Sagnac effect was originally derived
and experimentally shown first with light waves. However, in
recent years matter wave interferometers which use atoms
became important as matter wave interferometers are inherently much
more sensitive...
In 1998 I figured out that it is possible to make atomic gyroscopes
even better by
using a weird quantum effect known as Aharonov-Bohm effect which says
there is
a physical effect of potentials even though there is no actual force is
ever acted on
the particles...
"Influence of electric
potentials
on atom interferometers: Increased rotation sensitivity",
M. Özcan, J.
Appl. Phys., 83, 6185-6186, 1998.
Since then this continued to be my pet project as I am fascinated with
Sagnac effect and its close ties to
relativity. In
a Sagnac interferometer the medium in which the wave travels does not
affect the phase shift
against the common sense. So using a slower wave does not
increase the sensitivity!
However, my interferometer has another benefit: Unlike a Sagnac
interferometer it's sensitivity improves with slower waves!
This might have some other implications as well which I am currently
busy with...
Here is the Photonics
West 2006 presentation
and the paper is published as
"High Sensitivity
Rotation
Sensing with Atom Interferometers using Aharonov-Bohm Effect",
M. Özcan, Proc.
SPIE, San Jose, CA, Feb 2006.
and later... “Slow wave atom
interferometers for rotation sensing”,
Meriç
Özcan Proc.
SPIE 6482 64820V (2007)
"Jiroskobun Esasları,
Optik ve Atom Dalgaları İle Hassas Rotasyon
Ölçümü" (Invited Talk) Meriç
Özcan,
12.
EEBBM Ulusal Kongresi, Eskisehir, 12-14 Kasım, 2007. SURFACE
PLASMON RESONANCE BASED SENSORS
Surface
plasmon resonance (SPR) is a ligth induced collective oscillations of
electrons in a thin film of a metal. There has been numerous
applications of this phenomenon including bio-sensing and chemical
sensing. In addition to the sensor development, we explore
the increased photoluminescence due to SPR enhanced evanescent waves.
We also showed that SPR can be used as a highly sensitive
optical microphone or pressure sensor.
"High Sensitivity Displacement
Sensing with Surface Plasmon Resonance",
M. Özcan, Proc.
SPIE, San Diego, CA, Aug 2005.
ULTRA-WIDE
BAND (UWB) WALL
PENETRATING RADAR
We
actually built the prototype of the radar...You can read
some more here...
“Moving target detection using super-resolution algorithms with
an ultra wideband radar”,
Erman
Engin and Meriç Özcan, Int.
J. Imaging Syst. Technol. Vol.20, No:3, pages 237–244, 2010
“A
High Resolution Ultra wideband Wall Penetrating Radar”, Erman
Engin, Berkehan Çiftçioğlu, Meriç Özcan and
İbrahim Tekin, Microwave
Opt. Technol. Lett. Vol. 49, No. 2, 2007 A NOVEL
OPTICAL TWEEZER
We eplore the
manipulation of small particles non-invasively by using a focused laser
beam. Our unique configuration allows us
to use very low laser powers hence tweezing action
can be performed on live cells without causing any
damage to them. Computer generated arbitrary
trapping paths and time-shared trapping patterns
are successfully demonstrated. Currently we are
exploring evanescent wave structures for
manipulating nanometer size particles.
Here
is a
presentation of our
tweezer
and this work is published
as....
"A
compact, automated and long working distance optical tweezer system",
M. Ozcan, C. Onal, A. Akatay, J.
Mod. Opt., 53,
357-364, 2006.
PHOTONIC
CRYSTAL SENSORS
Photonic
crystals are artificially created periodic structures that modify the
propagation of electromagnetic waves.
In our unique setup we showed
that it can be used as a highly sensitive refractive index sensor,
orders of magnitude
better than the existing systems. This
system can be expanded to other sensor systems as well.
Currently
a US patent is
applied for...so
more info later...Atilla Ozgur Cakmak worked on this for his Master's
Degree.
Also,
we are working on Sonic Crystals in which we solve
acoustic
wave equations instead of Maxwell's.
Of course now we have to use acoustic
waves in the experiments instead of electromagnetic waves or
lightwaves.
Erman
Engin is working on the project for his Master's Thesis.
ULTRA
WIDE BANDWIDTH MICROSTRIP-SLOT
ANTENNAS...
This
was Aylin Eksim's master thesis work...We actually come up with
some neat antenna designs that worked
from 3 to 11 GHz range! We used a
few of these antennas in our UWB radar system actually...Never found
the time to write
something about them...
We eplore the
manipulation of small particles non-invasively by using a focused laser