The day 2 – fascinating plenaries, informative sessions and student reception

The second day at FiO turned busy and occupying. So busy that at the end of the day, I had to crash in the bed. This blog is therefore coming little late.

Bob has provided great near-live update of the plenary talks. The plenaries were really fascinating and enthusiasm of plenary speakers really palpable. Prof. Andrea Ghez made one of the best presentation I have ever seen and I hope to emulate her in future. The slides didn’t have more than 5 lines of text and a single graphic, which kept audience focused on what she was saying. I learned for the first time that there is likely a black hole at the center of every galaxy and its region of influence is called Schwarzchild radius. It is the radius below which a given amount of mass will collapse under the influence of gravity. It was fascinating to learn that the earth’s Schwarzchild radius is of the order of sugar cube and of the sun is of the order of a small university campus. However, I didn’t follow the notion that some galaxies have active nuclei that emit enormous jets of gas from their centers. If there is a black-hole at the center, how does that gas escape? Perhaps this gas escapes while whirling around the black hole at the edge of the Schwarzchild region. These ideas were followed by a discussion about the development of adaptive optics and impressive improvements that it provides when imaging stars.

Dr. Janos Kirz started from the origins of X-ray microscopy and brought the audience up to date with the state of the art. In effect, he summarized the key developments of the whole field in half an hour! It was curious to know that the refractive index of  some materials at  X-ray wavelengths is less than 1 and hence one can have total external reflection – a situation that I think does not exist (yet) in optical regime. He described idea of lens-less imaging in very intuitive terms. Basically, a lens can be thought of as returning us an object from the diffraction pattern. But if one records a diffraction pattern, the object can be retrieved by computation – bypassing practical issues of making a lens in X-ray regime.

Afterward, I attended sessions related to biomedical optics at Glen Ellen and gave a talk (about phase-space models for partially coherent systems) in the later half of the afternoon. All talks were interesting and some were really informative. It was great to see how non-linear optical method of CARS is giving molecular information without the need of labels. Several presentations were about design, implementation and application of new microscopic contrast mechanisms. I felt my presentation was well received and I could convey the big picture. But perhaps I put forward too many details. I felt so because some in the audience asked me to send more information rather than asking questions themselves. I hope to do better  at my next talk on Wednesday.

The day ended with a relaxing time at O’ Flaherty’s pub – the venue  of OSA student member reception. It was great meeting friends from all over the world and sharing their experiences. As I said earlier, I had to crash in the bed at the end.

Before the start of Frontiers in Optics – travel and lab visits

Before the conference started, I meant to post one more discussion about phase-space optics describing and simulating the notion of instantaneous frequency. But I will have to wait till my laptop agrees to the plan. I use LaTeX2WP (WP=WordPress) python script by Luca Trevisan for posting mathematical content, and somehow python refuses to get going on my laptop.  Apart from that minuscule disappointment, my time so far in the US has been fantastic!

I have been in the US since October 6 and done good deal of traveling. It is slightly unusual to travel before the conference but I need to return home just after the conference. I am recounting some of the exciting sights and university visits that I did. Hope someone traveling after the conference finds travel information useful.

Let’s go in reverse chronological order. I have  just returned half an hour earlier from a trip to lake Tahoe (right now it is 1.12 am of Oct 11). My friend working in the bay area drove me to this beautiful lake. You may already know that it is on the border of California and Nevada and is one of the most beautiful sights in the US. I learned that the emerald bay of the lake Tahoe is the second most photographed sight. It is a great place to enjoy water-scooter (which is called jetski here), motor boat, and para-sailing among other things. We reached there late in afternoon and wind had picked up (it is end of the summer season). So we were advised against para-sailing and jetski, but had great fun driving a motor-boat for an hour. If you plan to visit Tahoe, check with the people at rental business about the weather and what is possible. It is around 3.5 hours drive from San Jose/San Francisco and if you reach there before lunch, there are better chances of your being able to get more hands-on water experience than driving around a motor-boat.

Before Tahoe, I had the staple diet of tourists in San Francisco : Alcatraz prison, Golden gate bridge, Fisherman’s wharf, Segway tour, Exploratorium and Tactile dome. The first three sites I mentioned need no further mention.

I experienced the `personal transporter’ segway for the first time and I must say it is fantastic. The machine is designed to maintain balance – therefore if you lean forward, it goes forward to regain balance. This balance feedback loop is implemented very well and the machine seems to perceive driver’s intentions.

Tactile dome and the exploratorium were great fun too. Tactile dome is one of the exhibits of the exploratorium. It is a pitch-dark dome which you navigate using only your sense of touch. You pay 17 bucks to enter it (this fee includes entrance to the exploratorium). You have an hour to enter and exit this labyrinth as many times as you like. I found that if you are not scared of dark and just following your senses, you can enter and exit in 15 minutes flat. However, it is amazing that every time you go through it, you discover different structures inside it. I made two trips through the dome  and on my second trip, I discovered a place inside to seat and relax!

I had good brainstorming sessions at Stanford and UCSF. I visited Marc Levoy and Zhengyun Zhang at Stanford to take a peek at their light-field microscope. I found that they have another interesting project going on. It is dubbed Camera 2.0 and it is about designing an open-source camera with programmable hardware and software. Marc is presenting a talk about light-field microscope on Wednesday morning at FiO. We had a great discussion on phase-space representation of imaging systems (topic of my talk on Monday) and registration of gradient information measured through various methods (topic of my talk on Wednesday). Lab visits are great because they can add a lot of new perspective to your repertoire.

At UCSF, I was visiting Nico Stuurman and Arthur Edelstein at Ron Vale’s lab. My key reason for visiting them is their open-source acquisition software micro-manager. I have found this software useful for being able to construct useful automation for custom imaging systems and have contributed to a hardware driver for Olympus scopes. They are an enthusiastic bunch of people willing to make a positive impact in the microscopy world, where proprietary and closed acquisition software have failed to meet the needs of microscopy tinkerers. I shall be working with them to add support for the quantitative phase imaging method (AIDPC) – which we have developed.

An important note if you are visiting Stanford and want to catch some beautiful sights of the campus: make sure you DO NOT carry any heavy luggage (even 75% of the size of the typical cabin bag). Stanford has an arbitrary rule which prohibits even medium sized bags at places worth visiting (e.g. Hoover tower, Cantor arts center). That is not bad – what is bad is that they do not have any place for you to store it and even worse, they do not believe in verifying that you are not carrying anything dangerous.

That’s all for now. Tomorrow (sorry, today) morning is going to be an exciting day as the FiO kicks off . I plan to meet Milton Chang (a successful serial entrepreneur & venture capitalist and the keynote speaker at the OSA student chapter leadership meeting) to capture some of his views about entrepreneurship – especially in the area of open-source projects. Then there will be the ‘Hot in Optics’ summary from 4-6 pm at Fairmont. It’s going to be a busy day, so Good night.

Visa to the US for conference

A tidbit on the US visa may be helpful to some. If you are interested in optics or biomedical conference or exchange visit, and are a national of certain countries (India in my case, China in my friends’ case), it is rather important to start the process early. Earlier than what the embassy website usually advises. These applications tend to enter what is called ’special administrative processing’ (I presume) due to the sensitive nature of the subject. I was to attend SPIE’s Photonics West in Jan 2009, but missed it due to this processing which took more than 3 months. The results of that processing allowed me to secure the visa for the Frontiers in Optics  in two weeks. I was informed by the visa officer that, for first-time-applicants, the processing time has reduced from 100 days to around 6 weeks due to some recent reforms.

Frontiers in Optics (FiO)

Hello world,

I am excited at the prospect of attending this year’s Frontiers in Optics (FiO) for the first time. I am looking forward to its collegial flavor and high-quality work  in areas of basic optics, information processing, and microscopy. I also happen to be one of the official bloggers for FiO. I am not sure if this is the first year of inviting prospective attendees to blog about the conference, but it is a great idea for receiving honest feedback about the event. The message to the official bloggers from the OSA was not to be ’sales-persons’ for the conference but reporters true to their observations. Did I mention FiO is collegial? I look forward to meeting in person people coordinating this blogging effort – KiKi, Janessa, and Robert.

I haven’t yet sorted out finances, but I am hopeful. I am going to present two papers at the conference:

• The first one is about modeling of imaging  methods that use large illumination apertures (termed partially coherent imaging methods). A brief abstract can be found here. This work generalizes our approach of modeling the  differential interference contrast (as published in Optics Express here).
• The second one has more of an image processing flavor. It is about registration of gradients of given function. Registration of multiple measurements of a  2D function is well-studied in the form of image registration based on intensity correlation. But this framework is not applicable to registration of images obtained with microscopic methods that measure gradients of specimen’s optical thickness. I extend a robust image registration method of phase correlation to registration of gradient data. Abstract is here.

Our group has recently caught interest in phase-space representations (whose patent identity is Wigner distribution function) of optical signals and systems. I am particularly interested in phase-space analysis and design of partially coherent imaging systems. A useful review about phase-space optics can be found on Dr. Martin Baastian’s site who is one of the leaders in this area. It is great that FiO is going to have a special symposium on these ideas. Information about this and other special symposia is here. If you are going to be at the conference and have similar interests, we should meet up!

When it comes to optics conferences, a few come to mind just because of their shear size: OSA’s Frontiers in Optics et al., OSA’s Conference on Lasers and Electro Optics et al., SPIE’s Photonics West (PW), and SPIE’s Photonics Europe.  The ‘et al.’ hints to the fact that all of these are actually ’super-conferences’ comprising of multiple conferences. SPIE tends to consider each technical session a conference and therefore there are tens of simultaneous conferences. OSA on the other hand likes an approach of bringing together a set of large conferences. These large conferences let you find connections to your work in other fields. But you may feel lost among lots of parallel sessions and too many ideas ringing in your head.