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Monday, October 31, 2011

FiO 2011 - part 6 (final)

Hey everybody..  this is going to be the last post with my notes on Frontiers in Optics 2011.


Sergio Carbajo and Ying Geng won the Hilbert Grant award in
 optical engineering, lens design and illumination. Pic courtesy OSA.

Sergio Carbajo, from Colorado State University, who won the Hilbert Grant (in pic above) showed some amazing movies taken for nanoscale moving objects at near wavelength resolution. They have built an EUV tabletop laser and use repetitive nanosecond pulses from the laser with a zone plate objective to image the nanoscale moving object.

Ying Geng from Rochester, who also won the Hilbert Grant (in pic above), showed clear and sharp images of the mouse retina obtained using an adaptive optics scanning laser ophthalmoscope. The mouse imaging is very important for disease detection, diagnosis and cure because it is easier to find transgenic and knockout models of various eye-diseases in mice. But mice have notoriously poor vision. One would assume this should make for terrible images. But Ying managed to modify the beacon used for wavefront sensing to adapt to the unusually thick retina of the mouse (compared to humans). The beacon is now an annular shape instead of the conventional full uniform beam at the pupil and gives a tight sharp wavefront sensing spot allowing her to do adaptive optics sensing and correction. She showed images of the photoreceptor mosaic, blood capillaries, nerve fiber bundles. She also showed fluorescence labeled ganglion cells and even some results of classifying the ganglion cells into bi-stratified and mono-stratified classes which have dendrites (like roots) in two layers or one layer respectively. Very cool!

In the animal optics session.. 

Monday, October 24, 2011

FiO 2011 - part 5


Hey everybody.. FiO is officially over. But I am still processing the information from the sessions. In this post I'm going to summarize some of the talks I thought were interesting work. More will come later..

David Brady at the Hot Topics. Pic courtesy: OSA
In the Hot Topics session for information sensing and processing David Brady emphasized that optics is increasingly penetrating digital systems. Compressive measurement has started being used in optics and is increasingly more practical. Compressive measurement has now been demonstrated for projection tomography, snapshot hyperspectral imaging, OCT, holography, digital superresolution, etc. This year FiO had a tutorial talk by Rebecca Willett and a whole session dedicated to the topic. 

Serhan Isikman and M. J. Lee from the Ozcan group talked about...

Thursday, October 20, 2011

FiO 2011 - part 4 Eday

Hey everyone.. All is going great at FiO. Yesterday and today were full and busy days. But I do have some pics for you.

I went to Eday yesterday evening. This is an event the OSA organizes every year at FiO. They have volunteers, students and various chapter members from all over the world come in and give optics demos to teachers who wish their students to explore optics in their classrooms. This year's event was well attended.

They had lots of tables with various demos and a crowd of folks checking out the easy, inexpensive and interesting experiments these enthusiastic volunteers had come up with! I just took a couple of pics, here they are..

This is an undergrad student member, Denys Zaikin from Naples, Italy.



Denys had a demo for sustainability. He told us..

Tuesday, October 18, 2011

FiO 2011 - part 3

Hey everyone..! Another busy day.. let me tell you about some interesting folks I met today.

Animated discussions at the VIP meeting. Pic courtesy OSA.
In the morning I attended the VIP networking session. They had some very inspiring people from the optics industry – Karl Koch from Corning, Jean-Michel Pelaprat of Vytran, Michelle Holoubek, patent attorney at SKG, Richard Smart from Oclaro, Colin Seaton from Fianium and Ken Ibbs from LanTian Photonics. It was great to meet them in person and hear about their experiences and advice for working in the optics industry. Some of their advice included trying out places through internship programs so you can figure out what you want, making sure you fit in well with the work and culture of the team, and when you start working, try to learn the most you can from positions in your career. 

Laura, Donna, Jannick and Liz. Pic courtesy OSA.
In the afternoon I was at the Minorities and Women in OSA event where the panelists included very accomplished women in optics. Donna Strickland is a Professor at the University of Waterloo and works in ultrafast short-pulse intense lasers and non-linear optics. Jannick Rolland is a Professor at the University of Rochester and does very interdisciplinary and applied work in the areas of head mounted displays, augmented reality, illumination and freeform optics. Laura Weller-Brophy has vast experience working in industry at 3M, Kodak, and Corning. She is presently the founder of a start-up in Rochester, FluoroLogic Inc., which is developing devices for screening cervical cancer using fluorescence detection. Fluorologic has won several awards for their technology and business plan in Rochester. Elizabeth Rogan is the CEO of the Optical Society and has strong management experience in the corporate, federal and non-profit sectors.

It was great to hear these extraordinary ladies speak about working in academia, industry and management. They talked about the importance of support from family, mentors, colleagues and peers, gave advice for making choices in careers and a work-life balance.  

It was fantastic that the panel members in both events took the time and effort to reach out to us and gave us their best advice. Such interaction and support is amongst the greatest benefits of being in a professional society with a strong sense of community. 

Monday, October 17, 2011

FiO 2011 - part 2

Hey everyone..

Silicon Valley

Today was a busy day. I missed much of the morning plenaries. Apparently the organizers are uploading a lot of these talks online accessible to technical registrants. So I am hoping I can catch up with these things online later.

The afternoon had some exceptional sessions. Let me tell you about a few.

There was a session called "Phase". Sounded straightforward.. and as expected, all the works discussed in this session contained phase information in some way or other. Manuel Guizar-Sicairos from the Swiss Light Source in Switzerland talked about X-ray phase imaging. He discussed coherent diffractive imaging, ptychography, and 3D phase tomography. A coherent x-ray illuminated object is imaged in the far-field and algorithms such as used in phase retrieval approaches with suitable support, translation and Fourier constraints are used to recover object information. He showed some cool pictures of objects they have imaged such as bacteria in plant root nodules, nanostructure in bones and nanostructure in cement.. (Cement and bones in the same line sound odd, no?)

There were several other very interesting talks in the session. Adam Zysk from Illinois Instiitute of Technology talked about using task based assessment of phase contrast mammography. He had an interesting Bayesian decision maker that gives the best "discrimination" of calcification or other anomalies that may be identified by radiologists from mammograms.

Donald Duncan talked about extracting phase and amplitude from DIC images. Varun Raghunath showed some interesting work on non-linear imaging of phase and amplitude at the focal plane using heterodyne four wave mixing microscopy. Chien-Hung Lu from Princeton talked about using phase retrieval methods modified to adapt to non-linear media.

Later I attended the Compressed Sensing session I discussed in my earlier post. This session was good fun with a packed room full of enthusiastic and interactive audience. Rebecca Willet (Duke), Kenneth MacCabe (Duke), Lei Tian (MIT) and Sehoon Lim (Duke) gave interesting presentations on their work. 

That's all for today! Cheerio and thanks for reading!

Sunday, October 16, 2011

FiO 2011 - part 1

Hey everyone.. it's Sunday and the FiO crowd is starting to trickle into CA. I plan to meet some friends today, catch up and hang out a bit. Might attend a couple of sessions... if possible..

If you are visiting the Bay area for the first time.. there's plenty for tourism..


.. a stroll or hike through some of the woody trails.. maybe a picnic lunch..


.. and good eats!


Looks like OSA is also organizing visits to the Winchester Mystery House, Santana Row on Monday, 10/17 and to the Tech Museum on Tuesday, 10/18. Seems open for all OSA members, family and friends.

Look forward to a great week!!


Wednesday, October 12, 2011

Astronomical Scintillations

My first trip from grad school had been to the University of California at Santa Cruz for the Adaptive Optics Summer School held by the Center for Adaptive Optics (CFAO). I was very excited and the visit did not disappoint. We had learnt lots of adaptive optics and met a lot of people doing great work in the area.

Lick Observatory on Mount Hamilton. Picture from Wikipedia

And the best part of the trip had to be the trip they organized to the Lick Observatory at Mount Hamilton. The winding roads and breathtaking views led to domes that housed the most amazing optics and astronomy. Elinor Gates, a scientist at the observatory, was the most knowledgeable host we could have hoped for! She showed us around their adaptive optics setup, their telescopes, and narrated some very engaging ghost stories whilst setting up a smaller telescope on the night sky! It was an absolutely starry and spectacular night!

So some weeks ago, when the N-Cal OSA committee here asked for local speakers, I immediately thought of Elinor! Would be good to catch up with her and see what’s new at the Lick Observatory! Elinor kindly agreed to give us a talk on “Untwinkling the Stars.”

Elinor Gates chatting with folks after the talk

The Lick Observatory is an astronomical observatory on the summit of Mount Hamilton, east of San Jose, founded in 1888 by the bequest of James Lick. They have several telescopes like the 3m Shane Reflector which has adaptive optics on it, the 1m Nickel Reflector and a couple of smaller telescopes and accessory equipment.

Monday, October 3, 2011

Holography

Holography has been a technology that has fascinated people for many years. It has featured in movies, books, comics, cartoons.. it’s like a technology that’s just got to be!

Bad hair day..

A hologram is a recording of the interference between light reflected from an object and a pristine reference beam. If later you illuminate the recording with a beam similar to the reference beam, it re-interferes and re-creates the appearance of the original object. The benefit of a hologram compared to a 2D picture is that you can look at the object from different angles and the object retains depth information.

Recording a Hologram. Figure from Wikipedia.
Film or photographic emulsions are common media for recording simple holograms. Lately much progress has been made in Digital Holography where the film is replaced by a sensor like a CCD. This allows us to reconstruct the hologram entirely digitally, without illuminating it with an actual beam of light.

Computer Generated Holography is when you digitally create a hologram of an object; there’s no reference beam illumination, no actual interference of light. That makes it possible to create holograms of completely unreal objects.

The most basic holography (shown in the figure above) is done with coherent laser light. But it is also possible to do holography with white, incoherent light. For instance, techniques like Scanning Incoherent Holography and FINCH (Fresnel incoherent digital holography) give incoherent light holograms. It is also possible to capture multiple images of the object from different angles using a normal digital camera, no reference beam, no interference and then digitally generate a hologram from a combination of those views.

There seem to be several good sessions on holography at Frontiers in Optics this year on Tuesday and Wednesday morning - FTuF, FWJ. They have some of the best speakers giving invited talks on this topic. There is also quite a bit of recent research in holographic microscopy, computer generated holography, synthetic aperture digital holography that I can see in the sessions. Surely worth a dekko!!

Cheers and thanks for stopping by!