Open-Source volumetric display

[Ed Wesly]

Dinesh wrote:
TJ (no less!) enthused about the "CNN" hologram. I stated that TJ was wrong and this was not a hologram. However, due to this "ancestral worship" dimension of old holographers, I was taken to task for daring to disagree with TJ! (Luckily I'm not much of a believer in the "expert syndrome"!) Now, I have the greatest respect for TJ, but in this case he was wrong!

This forum is lucky to have me as a fact checker. This time Dinesh is entirely wrong, more than likely to further his own self-aggrandizement. (“In the land of the blind, the one-eyed man is king.”)

In an e-mail I received:

“From: TJEONG
To: cubit@lakeforest.edu
CC: schappe@lakeforest.edu, kash@lakeforest.edu, crist@lakeforest.edu, macracke@lakeforest.edu
Sent: 11/7/2008 9:50:50 A.M. Central Standard Time
Subj: holography in the news

Hello:

Please let it be known that I am invited to participate in a live interview on National Public Radio (FM 91.5) on Tuesday, Nov. 11, from 11:00 to 11:30 am. The subject is Holography.

A report in the Nov. 5 Chicago Tribune carried an article on holography in which I was vastly misquoted. The reporter, Steve A. Johnson, has made “corrections” in his blog:

http://featuresblogs.chicagotribune.com ... holog.html

Tung H. Jeong, Physics”

He clearly states that he was misquoted, and if you follow the two included links you will see that he was dissing the “holograms” from the start! I do not know if the NPR broadcast is archived.

On another topic, from the FaceBook site, “I also have a buunch of Wheatstone pair pictures and a Wheatstone stereo viewer.”

I seriously doubt that Dinesh has a Wheatstone Stereoscope. These beasts were the very first types of stereoscopes and their configuration is bulky and difficult to align.

Wheatstone Stereo Viewer

If he’s lucky, he has a Brewster stereoscope, which were more prevalent in jolly old England, but more than likely it’s a Holmes Viewer, the standard of the industry in America. Millions of stereo views were printed in a standard format in the 19th century, one of the mainstays of the wet plate Collodion photographer. Please post us a picture of your genuine Wheatstone if I am in error.

Brewster Stereo Viewer

075.gif (29.18 KiB) Viewed 3471 times

And in another hard-hitting investigative reporting act, when and where did you have the conversation with Denisyuk about your “resonance” hologram? “I also at one time created an optical amplifier using holographic principles. It basically exploited optical resonance between two sets of Bragg planes.No one believed it. Not even Joy who actually took measurements and could see that more ight was coming out of the hologram than went in.” Isn’t this perpetual motion?

And while I’m on a roll here, at first you were dissing the carbon nanotubes as not really holographic. Then you state that you had thought of using them as early as 2003. How would you record a hologram using these nanotubes?

BTW, thanks for the plug for my web site in another thread.

And don't think I am busting your b**ls unfairly. It rankles my educator training to see someone who stretches or fabricates reality to make themselves into something they really aren't. Someone needs to keep you on the straight and narrow.

[Dinesh]

He clearly states that he was misquoted, and if you follow the two included links you will see that he was dissing the “holograms” from the start! I do not know if the NPR broadcast is archived.

If it was published in the Chicago Tribune, it was published nowhere else. I don't believe that the whole world reads the Chicago Tribune - despite Chicagoans belief to the contrary. The point was not that he was misquaoted. The point is that when his original quote was published none of the holographers mady any kind of statement concerning the error.

And in another hard-hitting investigative reporting act, when and where did you have the conversation with Denisyuk about your “resonance” hologram? “I also at one time created an optical amplifier using holographic principles. It basically exploited optical resonance between two sets of Bragg planes.No one believed it. Not even Joy who actually took measurements and could see that more ight was coming out of the hologram than went in.” Isn’t this perpetual motion?

No, it isn't. That was the feeling amongst a lot of people. Only Yuri saw that it was physically possible. The whole point of an amplifier is that it amplifies, however amplifiers don't violate entropy. It depends on how you define "amplify". Any resonant system will amplify because the Q value goes up, not the total energy. Your radio is a resonant circuit with amplification. You seem to have missed the fact that this was an optical resonant circuit. The response function, in the limit, approximates to a Dirac delta function whose integral is unity, even though the amplitude is infinity. When and where? Well, it was off the main conference hall in San Jose, when SPIE took place in San Jose.

Then you state that you had thought of using them as early as 2003. How would you record a hologram using these nanotubes?

Define "record". You can however use them as resonant chambers. My idea was to place a series of nanotubes inside a matrix at regular intervals, let's say at n*lambda/2 inside a matrix of m*lambda. Then you block off the ends. Inside the nanotube, the solution would be a Bessel Function, since, by virtue of it being a nano-tube, the diameter is less than lambda for vis. This would create a series of Bessel function index variations deispersed in a regular array iin the matrix. By appropriate use of the Bessel coefficiants, you could create a Bragg structure.

And don't think I am busting your b**ls unfairly. It rankles my educator training to see someone who stretches or fabricates reality to make themselves into something they really aren't. Someone needs to keep you on the straight and narrow

Perhaps if you learned a bit of elementary mathematics and physics you might understand me better! You don't seem to understand resonanance phenomena (besides googling "resonance"!), you don't seem to undertsand the value of Bessel functions in an optical communication system (besides googling "Bessel") and you certainly have a layman's understanding of "Perpetual motion" since you probably don't understand "entropy" (besides googling "entropy!) All you're doing is stirring it up for your own reasons and your own ego. You have no idea what I have. If you do have a physics degree, perhaps you might let us know what university and post a copy of any technical paper you've published. This stirring it up does nothing more than damage the integrity of the forum and I have tried hard accomodate it politely, but still you persist.

So, one more time, resonance does allow amplification. Yuri was a dam sight more of a physicist than you are (assuming you've actually done some physics). You can use nanotubes as resonant standing wave structures - as you would know if you actually studied physics.

What I have depends on what I decide to spend in which place. There are a number of antique shows in San Diego. I, at least, have the means to throw thousands of dollars at something I want without a second thought. So, you're statement that I don't have a wheatstone is yet another barb at me personally. Being an educator has nothing to do with whatever problem you seem to have with me.

We can continue this on and on and on. Your choice. Let me re-iterate. I am a physicist. I have degrees from King;s College London in a joint honour BSc in Physics and Mathematics. I have an MSc in Quantum Electronics, I have a DSc from Imperial College, London in Theoretical Physics under Professor Abdus Salaam. have another MSc from Birkbeck College in Fundemantals of Quantum Field Theory under Prof David Bohm (yes, that Bohm). Whether you "believe" this or not is no concern of mine. I have a lab with over half a million dollars in equipment, none of it from any bank loan, it's all ours free and clear. I spend a lot of time doing my own research. Some of it is mathematical; right now I'm looking at generalising Kogelnik into a generalised coordinate system. None of this and the work I've done in the past will ever get published. I don't have the massive ego you seem to have! For your information I have an email from Hiroshi where he states that he was impressed by my research when he visited me . Luckily for me I don't have a giant ego like you.

In conclusion, I am not a display holographer, like you. I'm a scientist. As a scientist, I can debate science and physics with other scientists, not overt personal barbs simply to air a massive ego!

This does the forum no service, but I'm prepared to continue this as far as you want. Googling "Resonance" or "Dirac delta" or "entropy" will only get you so far. You seem to have no idea what my personal wealth is and how much I have invested in antiques, so you have no basis to decide what kind of an antique collection I have. Again, an obvious and egotisitical barb with no evidence whatsoever! This latest barb originated with you and only you. You seem not to understand resonance or Bessel functions. So, if somehow Ahmet thinks it's all my douing and wants me off this forum, it's his prerogative. Ahmet, I hope you realise that this barb was unfounded, ignorant in its accusations and purely personal. It's your (and the rest of the forum's choice).

" hard-hitting investigative reporting act" If your investigative skills are like your educating skills, I feel sorry for your students! They must only learn the unsubtle Wesley technique of throwing vitriol around to those who don't worship him!

A lot of people seem to think I originate these arguments. I think it;s now fairly clear that you come from ignorance of my financial and educational status and proceed from there. But, if the forum members think this is my fault, I'd be happy to retire.

I think the forum members need to get involved here and make themselves heard or these vitriolic attacks (and I'm not fooled by this statement about breaking my parts!) will simply continue every time I post something and I'm not one to take it lying around, as no doubt some of the Wesley victims have done!

[Ed Wesly]

What about the Dinesh attack on TJ?

[Dinesh]

I did not attack TJ. Only Wesley attacks, throws personal barbs and vitriolic attacks with little understanding of the facts, which don't seem important to him. If Mr Wesley objected to some statement that I made concerning TJ, then that should have been the subject of discussion, not personal barbs and unsupported statements passing as "Investigate".

TJ made a statement apparently approving the CNN hologram. If he was misquated, this was not widely reported. The facts, on the face of it, were that TJ was apparently promoting the CNN hologram. This is the information I and probably several others received. At this point, TJ had apparently committed an error (he's only human and can commit errors, unlike Wesley, who apparently cannot!). I pointed out the error. No other holographer did. No one, repeat no one, is above making errors (except of course Mr Wesley) and if an error has been made, it's necessary for others to point it out. This is common in the scientific literature. This is how scientists are educated. Anyone who reads Physics Today will see the letters page full of disagreements, but these disagreements are carried out in a refined and dignified manner, not with the vitriol we see here. The scientist in question can then state that he was misquoted, or he/she can defend the error or admit to it. All three take place in the scientific literature. The reason for publication and peer review is exactly to weed out errors and missteps and/or to defend an apparently non-intuitive proposition and all scientists are made aware of it very early in their carrers.

Let me also point out that scientists are under attack because the lay public do not understand the science and the scientific method, and because the lay public then attack in this virulent manner without understand the ebb, flow and refinement of scientific disagreements. In fact, these days scientists have to be awfully brave to state anything at all and science itself is under attack. Most of them simply retreat under the face of these concerted attacks since they only know the genteel methods of answering critics. As far back as the mid-70's scientists like Sagan, Asimov and Feynmann deplored the fact that scientists did not go on the offensive, giving rise, in my opinion, to this period of abject superstition. There is a prize being set up to reward the courage of scientists who "fight back" at great costs to themselves. Sunny Bains has asked Joy to contribute names towards that prize.

[PinkysBrain]

They bring on these "perfessors" would you believe, who keep saying estropy, no enropy, no - oh yeah entropy!

Of course if they got a methemetishan, kemist and wantum meganikal fishashit perfessor they'd all be talking about a different thing.

[Dinesh]

They bring on these "perfessors" would you believe, who keep saying estropy, no enropy, no - oh yeah entropy!

Of course if they got a methemetishan, kemist and wantum meganikal fishashit perfessor they'd all be talking about a different thing.

Dam right about the kemist! They seem to forget that their entire subject is but a subset of our subject! I'm joking! I don't want to see a horde of chemists outside my front door with lighted torches. In college there was always a rivalry between the chemists and the physicists. As for the meth types, they tend to despair of us because we're not as rigorous as they'd like. For instance, we talk blithely of integrals with infinity as a limit or simply assume that any series that deals with a physical concept must converge. These meth types tear their hair out because we don't prove convergence. And, what on earth is "infinitesimally small"?! When you first study calculus, you're told, "Take the limit as delta x becomes 'infintesimally small'". When I asked, in class, exactly how small that was, I was asked (forcibly!) to just leave it alone and follow the argument. To this day, I still don't know how small 'infinitesimally small' is. I mean, are we talking Planck length now?

[Dinesh]

By the way, Pinky, apropos of the physicists/chemists and mathematician comment, I assume you're implying that the vocabulary and/or the jargon mean different things in these different disciplines. Well, yes and no. We all use the same concept, but we have different units and perhaps different standards. For example, the chemists' measure of mass is the mole, while our measure of mass is the kilogram. The chemists measure heat in kcal/mole, we measure heat in Joules. But both the chemists and the physicists base these measurements on Avagadro's number and PV = nRT. Talking of Avagadro's number, we were given a problem in Avagadro's number in a physics class, but we had just covered Avagadro's number in a chemistry class the previous week. So, as soon as the physics teacher put up the problem, we all blurted, "But, that's chemistry, sir!" Whereupon the physics teacher told us the following story:

Teacher: "If I have 5 apples and I take away three apples, how many apples do I have?"
Johnny:"2 apples, miss"
Teacher:"Very good, Johnny! Now, if I have 5 oranges and I take away three oranges, how many oranges do I have?"
Johnny:"Dunno, miss. We haven't done oranges"

[favalora]

I hope to bring this conversation back to the original topic by pointing out an example halfway between "definitions" and "volumetric displays." Gas mileage is in inverse meters^2: http://what-if.xkcd.com/11/.

Don't worry, Dinesh, this is not the radiometry / laser pointers-at-moon one.

g

[Dinesh]

Well, for the birds, we can probably give a better estimate than that. The basic problem is:how many birds will flyoverhead over a given period, d(bird)/dt. Once that is established, the next question is what the poop rate, d(poop)/d(bird) is. Then,

(d(bird)/dt)*(d(poop)/d(bird)) = d(poop)/dt.

d(bird)/dt would depend on the average bird population in your neighbourhood P_bird/unit area. So, define "neighbourhood". We can set up a reasonable derivation by describing the time of flight of the average bird, t_b (I'm not taking seasonal or diurnal variation into account, though that can be done) and the average velocity of the average bird, v. Thus, the "bird flux" is:

(d(bird)/dt) = P_bird*A*v (the number of birds that are one second away from you.)

Now, d(poop)/dt is a little more difficult. However, pressing on, do birds follow a circadian rythm? Let's assume "yes". Then, d(poop)/dt would depend on some time after they fed t_delay. When they fed would depend on their circadian rythm, let's call that R(t).
So,

d(poop)/dt = R(t) + t_delay.

Now we need d(bird)/d(poop). This is tricky. Let's assume a Gaussian function of the population. So,

d(bird)/d(poop) = exp(-a*P_bird)^2

At this point, a little algebra will allow a first order differential equation that can easily be integrated, in terms of bird population in your area, the circadian rythm of a bird, the digestion time of a bird's stomach and the average velocity of a bird. These factors are capable of experimental verification/discovery.

For the gas mileage, you'd have to do a line integral, since the car is not going to be travelling at the same speed along the "gas line", as well as the gas consumption of your car as a function of speed. So, you'd have to line integrate from inital position to final position the function v(t)*g(v). Since this integral is clearly path-dependant, the force on the car is not conservative. Therefore the curl of the transport vector is non-zero, which explains why people driving a car always refer to "taking her out for a spin". We are not sure what determines the sex of the car. When one of the authors (me), took the car to a garage and asked them to lift the car in order to determine it's gender, the garage owner called the police, which resulted in this researcher having to abandon the research protocol rather quickly!

By the way, did you ever see the Fermi problem "How many piano tuners there are in Chicago?" He used to give this problem to his students to teach them how to set up an approximate solution http://www.grc.nasa.gov/WWW/k-12/Number ... _tuner.htm

[Thomas]

But even with a name like "HoloDome" its a neat little toy.
Except for selfmade LED-3D cubes there is no way I can get my hands on something like a volumetric display or even a electro-holographic one.
They simply don't exist as finished, buyable products (..well for under 50'000 or 100'000$) . And because I'm really curios what the future of display technology will bring us I'd like to play with one of these.
Just for fun and to see if there is something useful to do with such a thing...

Yes this is not a hologram or a holographic display and they don't called it one. It's probably called "HoloDome" because everybody (except real holographers and researchers working on this kind of display tech) would and will call this a hologram. In the mind of most people everything which seems to be 3D and floating in air is a hologram.
It's like the floating glowing things in the movies...

So if their kickstarter thing works out, they offer a "maker kit" for 300$ and you need the dlp development mini projector for 350$ and you need to build some things for yourself as well (?.. don't know what exactly..)

this sounds pretty cool to me. maybe I pledge too .. but 650$ is quite a bit of money for a nice toy to play with