A lot arcane physics for one device. Developing this to a useful commercial product must have been daunting.

@rkan2

2 жыл бұрын

Judging by the "Dr. William E. Glen suggested this basic method of generating colored light by selecting the desired portion of the developed spectra from a phase grating written on a fluid surface" seems at least he had a quite clear picture of how to manage it. I imagine it might have been more simple than you'd think when you'd understand optics and a bit of fluid dynamics.. Ok maybe a bit of mechanical and electrical engineering too :D

@gregorymccoy6797

2 жыл бұрын

@@rkan2 exactly... magic 😀

These Talaria projectors were the "Gold Standard" in their day. GE projectors were based in Syracuse, NY. They were initially created in B& W for the military, who was interested in the brightness they provided. They were too expensive for commercial use (i.e. Boxing matches in rented movie theaters). After color TV became viable and later commonplace, the color versions shown here were developed. To put things in perspective, despite of the apparent complexity shown in the drawings, these were an order of magnitude more light efficient than early LCD projectors in the late 70s. Resolution was better than "Broadcast TV" (i.e. ~ 450 x 240 in B&W roughly similar to a VCR) especially in color. "Broadcast TV" has about 1 MHZ color bandwidth which is less than 1/4 of the luminance / B&W bandwidth, or ~ 110 lines vs 450 lines. These are vertical lines of resolution, not the number of scan lines of the raster. One of the fun things to do in the late 70's was to photograph a car's red tail light and watch it on a color TV, press the brake pedal, and note that the red color was much larger than the actual tail light. Most Talaria projectors were replaced in military use by the Hughes light valve projector which worked by using an LCD window which was raster scanned as a reflector of a powerful xenon lamp. This had full RGB capability, variable scan rates for higher resolution. They were deployed in the "situation rooms" not only on land, but also on aircraft carriers. Delving into TV technology is fascinating and reveals the ingenuity of talented people. Video tape recording is another aspect, which adds a lot of mechanical complications to the puzzle. That old VCR in your home is the most complicated, precision technology in the consumer's hands, yet at a very affordable price. It still is (much more complicated and demanding to make than even a "super-duper" gaming computer with VR headgear).

@evghenim1955

2 жыл бұрын

Not to diminish the precision of VCR technology, but I have an impression that modern hard drives (spinning ones) are on a whole another level of complexity and precision.

@shazam6274

2 жыл бұрын

@@evghenim1955 Hard drives are indeed precision devices... but they have only two moving parts: rotating discs and angling heads. The heads are not touching the magnetic coating of discs, but "ride" several molecules of air above it (i.e. "Winchester technology"). In VCRs, from 2" quad machines to small 8 mm cassette camcorders, the heads not only contact, but also actually "penetrate" (deform) the magnetic coated tape, which is wrapped around about 180 to 270 degrees around the rotating head. And then there are the double and triple nested PLLs for controlling the head drum and capstan. The head drum speed and tape speed not only have to be precise and matched to the signals on the tape, but also correctly in phase. Hard drives only record "1s" and "0s" while video recorders record several analog signals which vary over a 40 dB range and are AM, FM and PM modulations and have an additional two sync signals for timing. All this, in a woodgrain style plastic case, TV tuners, timer and remote control for under $80, which was a fraction of the cost (at the time) for most hard drives. Amazing!

@hightechstuff2

2 жыл бұрын

@@evghenim1955 Yes, but not nearly as many moving parts. Both are amazing in their own right.

@Mikkel324

2 жыл бұрын

I managed to dig up some info on the Hughes light valve, it's a pretty interesting technology as well, though not nearly as clever as the Talaria. Surprisingly enough, it's not based on raster scanning, at least not early models. It seems to have been built around reflective LCD technology, controlled by a photoresistive layer coupled to the face of a small CRT. The light valve itself was a sandwich of layers, converting the visible light image from the CRT into a reflective image, which is then used to gate the light from the usual xenon arc lamp.

@shazam6274

2 жыл бұрын

@@Mikkel324 Kind of... The ~ 3"CRT was raster scanned to modulate the ~ 4" diameter LCD cell whose 2 electrodes had a bias voltage applied which was gated to extinguish each raster image. Even though the CRT emitted a visible raster image, the LCD was mostly responsive to the heat of the image. As for cleverness, the oil film light valve of the Talaria and Eidophor projectors was indeed a very clever solution, albeit, extremely complicated and critical to make.

So from what I understand: a electron beam tickles some oil to filter light in three different channels to make an image. This is insane.

@blackrockcity

9 ай бұрын

Its more insane than that. You use the words "tickles" and "filter" too casually. kzread.info/dash/bejne/qZNtsMqid8jRnKw.html

This technology makes nuclear physics look like it could be simply written into a Haynes Manual and a working nuke could be knocked up over a weekend in your shed. Brain melting stuff!!!

@rkan2

2 жыл бұрын

AFAIK making a traditional fission bomb (not fusion/H-bomb) is not technically that difficult but it is very resource intensive. With todays technology and no restrictions you'd probably need a few hundred million $ to a couple billion to create a uranium-derived A-bomb. It seems to also be more easy to make a dirtier bomb (bomb that doesn't use all the fissile material in the explosion) than a cleaner bomb that consumes all of the uranium (or plutonium in a nuclear reactor derived bomb).

@roberthorwat6747

2 жыл бұрын

@@rkan2 yes thankfully you are correct. Great explanation why here from The Engineer Guy: kzread.info/dash/bejne/gZebraaMp6y0f6Q.html

@uploadJ

Жыл бұрын

re: "This technology makes nuclear physics look like it could be simply written into a Haynes Manual" Look up the story about The Nuclear Boyscout to see how someone was well on his way to do just that ...

Goes to show when you have limited technology you find ways to make things work, there’s loads of 1940s and 50s tech that’s extremely hard to understand by modern analysis, but would probably be fairly straightforward to those who only had tubes and discrete components.

Interesting, that electron tube "thing" attached to the bottom is a ion pump type of vacuum pump.

@dcmoisan

2 жыл бұрын

Looks like the granules in that area are to absorb molecules from the oil. Tim Hunkin would say that it's amazing that it works at all! And he would be right!

its one thing to imagine this in a lab, but can you imagine making it work at 30-60fps? also how many prototype it might have took to make it work correctly.

We used Schlieren photography in uni to take images of supersonic shock waves in a wind tunnel. Amazing to see it used for this!

Absolutely brilliant of them to use the horizontal raster line spacing to be the green diffraction grating... while drawing the vertical diffraction grating for red and blue combined...

Somebody ping Ben Krasnow. Maybe he can whip up a prototype of one of these in his garage over a long weekend.

@rdoursenaud

2 жыл бұрын

He was on the comments of the previous video. Guess he’s already improving on the design ;)

@witeshade

2 жыл бұрын

honestly i'd be shocked if maybe a year from now, ben doesn't have a video where he manages to get an oil diffraction film to generate a color pattern of some kind.

@rkan2

2 жыл бұрын

@@witeshade Mike seriously needs to send him the oil - it seems like analyzing and making that work is much more in his area!

Pay walls, yeah, I've noticed that about so many scientific papers. What a world we live in.

@dtiydr

2 жыл бұрын

Its a reason for that so scientific discoveries and similar should not as easy be spread around the world.

@vincei4252

2 жыл бұрын

@@dtiydr But if you pay they can spread?

@paulhawkins6415

2 жыл бұрын

@dtiydr China says 'hold my beer'

@dtiydr

2 жыл бұрын

@@paulhawkins6415 They sure will try if there is money to gain.

@dtiydr

2 жыл бұрын

@@vincei4252 I said "not as easy" and then they also know who, and might not give access to any specific country either. I also strictly meant scientific discoveries in general, this is just a pure patent and its a bad example for that. Pure scientific discoveries in one way or another is held closed in a box in a dark corner for the majority of the world or in a secure computer center somewhere. Which is why the chinese and russia fex try to break in and steal it all as usual.

The book "Color In Electronic Displays 3" by Widdel & Post references this and appears to have a good amount of information on this technology and other similar tech. Looks like you can grab a copy for £35 second hand.

@Mikkel324

2 жыл бұрын

I found a pdf copy of the book, it only contains a few pages on the Eidophor and Talaria, but they manage to explain the technology pretty well. It also has a few subchapters on other interesting projection technologies, among them the Hughes light valve mentioned in some other comments here.

Nice follow-up Mike, thanks!

These early large display videos are really good, hope you have plenty more planned. Demonstrating a working Talaria would be interesting, hopefully you can find one at a reasonable price.

Mind blowing indeed. Plenty to think about.

If you wanted to bypass the paywalls by entering the URL of interest into sci-hub you should NOT as that would deprive the copyright holders of their right to extract value by restricting access to 50 year old scientific papers

@YSoreil

2 жыл бұрын

Yes, it is very important to NOT do that.

@mikeselectricstuff

2 жыл бұрын

Yeah thanks - I didn't just do that and put links in the description.

@vincei4252

2 жыл бұрын

These (expletive deleted's) cry into their milk every day that they were not able to paywall f=ma or e = mc^2

@AndrewGillard

2 жыл бұрын

(For those unaware, I believe that, for most scientific papers, it's _only the journals themselves_ that profit from the paid access to these things. The scientists and researchers who did all the work don't see any of it - and are often funded with public money. The excellent Medlife Crisis channel has a video about this, including an interview with Sci-Hub's creator: kzread.info/dash/bejne/gqad2aWiZrbgfNI.html )

@Anvilshock

2 жыл бұрын

I would NEVER do that.

Invented by Good and True :-)

Wow--that's from Syracuse. My father used to work at the GE TV plant in Syracuse (many decades ago--in the late 60's/early 70's) and I grew up living walking distance from it. Don't recall him ever working on this, though. Now, that plant is owned by Lockheed Martin.

@blackrockcity

9 ай бұрын

Lockheed owned the Light Valve technology at some point. Maybe someone here knows more about that?

Interesting ingeenering for sure, really coll stuff!

amazing!

As fantastic as Disneyland, but almost as alien as Roswell.

This is mind blowing, reminds me about oil changing color when reflecting light, it should be called thin-film interference.but this something different I guess.

@pizzablender

2 жыл бұрын

It's more like the colors you see in the reflection of a dvd or cd.

@Marci124

2 жыл бұрын

@@pizzablender The same effect is behind both, thin-film interference.

@Muonium1

2 жыл бұрын

@@Marci124 no it isn't. thin film effects have nothing to do with the dispersive qualities of CDs

If you replaced the lamp with a coherent light source, I wonder if you could raster the diffraction pattern of a hologram.

@blackrockcity

9 ай бұрын

I suspect you will encounter some resolution problems but I'm not expert enough to be conclusive.

I wish there were some of these working somewhere, it would be great to be able to see how good the picture quality is. I would imagine the saturation would be pretty low, but then so was the 70's colour CRTs :)

@electronash

2 жыл бұрын

There are a few short clips here of the projector itself, but sadly none of them pointed at the screen... /watch?v=yj69t1l7BQA

@blackrockcity

9 ай бұрын

The projector was NTSC/VGA because those were standards. But the technology was capable of higher resolution. The three beam GE MLV probably was higher resolution. The image had refresh latency sort of like phosphors of a CRT that would glow for a bit too long between frames. It definitely had a unique analog look to it due to the oil causing the image to sort of bleed around. An ambitious project would be to adapt modern video electronics and CRT modulators to up its resolution. But that would be a science project, not a competitive/practical tool. The xenon lamp required a 240v wall receptacle... for an image with far less resolution than an Apple Watch. But at the time, the brightness meant you could have long beam throw distances (different projection lenses were available if I recall) and very large movie screen sized images .

The name "talaria" and the way it works sounds like a magic spell from a Harry Potter book

The way I understand with the quick read while the video was playing is. They have color filters on 3 zones of the illumination source that pass trough a mask. Conventionally the electron tube is writing lines onto the oil film, as would onto a CRT screen. Within those lines they modulate the 'energy' to create vertical ripples, so the diffraction matches with the output mask ans color. I suppose the output mask is there to reduce bleed and only allow the light/color that gets focused in the correct geometry trough that mask. It seems a bit like radio amplitude modulation to create the grating waves and beam power to write the image information.

@SarahKchannel

2 жыл бұрын

The colors dont come from the diffraction, but rather from the selective matching of refractive index, generated by the 'waves' in the oil, to the output mask. Hence the term light valve, since it 'bend's the light so only one color at the time matches the output grating. When nothing is written the input mask, cancels or is blocked by the output mask. When the light is refracted correctly is can pass trough the grating.

What was the quality of the projected image?

@Mister_Brown

2 жыл бұрын

pretty terrible by today's standards but these were used often things like screen projection behind a rock stage of the ongoing concert so it didn't matter much, anyone close enough to see how bad it was wasn't looking at the video but the actual performer, so by the time you got out to the range you'd be watching the screen it was alright. a few of the papers refer to something on the order of 200-300tvl which is around what you can expect from the best standard VHS can do but probably with quite a bit more color resolution

@ObviousSchism

2 жыл бұрын

@@Mister_Brown Thanks for the informative response. I now have a good idea of what it looked like.

@tekvax01

2 жыл бұрын

It said right on the screen in the patent that they were achieving 600 to 900 lines of resolution.

@pizzablender

2 жыл бұрын

@@tekvax01 600 to 900 lines is much better than NTSC transmission, as stated in the marketing material.

@blackrockcity

9 ай бұрын

The technology was capable of higher resolution than the NTSC standard... so it was the standard that limited the projector's resolution, not physics. I have yet to have seen a Talaria with properly calibrated color, so I'm not sure what color gamut it is capable of.

I've been non-stop researching this s*** ever since your previous video.

So it’s generating diffraction gratings in real time? That’s cool!

Hi, maybe you can light up this whole thing like it must work? It would be really interesting to see real image of colors squares (or circles) in place of rotating plate. Just white paper can be in place of plate

IMO, a 2021 equivalent is the incredible technology behind Extreme ultraviolet lithography.

So for over my head it spins. Really interesting thing to geet hold of.

This is hard to believe that this was from the 60's 70's era. Would just love to know what secret stuff this made happen. I would bet you the average person does not even have a clue.

Go William go go go... William E. Good

Are any of the inventors of this still alive and up for an interview? Veritasium?

@techobsessed1

2 жыл бұрын

That seems unlikely. The original invention and development was in the 1940s.

👍👍👍

Nice, I did not evn know this teck exsited. It's a shame so much of this engineering knolage from the past seems to be getting lost.

@yuribochkarev4477

2 жыл бұрын

this part is already completely lost. Today I learned for the first time that such a thing existed at all

@Marci124

2 жыл бұрын

Nevermind all the spelling knolage lost.

I have two talaria complete projectors but haven't checked to see if they work or not.

@FrozenHaxor

2 жыл бұрын

What sort of video input format/connector do they accept?

@Tadesan

2 жыл бұрын

Don’t scrap them! Make vids or get them to somebody who can!

@blackrockcity

9 ай бұрын

@@FrozenHaxor VGA and three component BNC if I recall. Therefore modern computers can drive these projectors with the right dongle.

@FrozenHaxor

9 ай бұрын

@@blackrockcity Woah, I wouldn't expect VGA on such vintage projector at all! Interesting, wonder what the refresh rate would be in Windows haha, probably a smudgy cursor from the oil refresh system.

@blackrockcity

9 ай бұрын

@@FrozenHaxor the inputs on the projector are three component. It’s trivial to adapt that to VGA with a $5 dongle. If you Google image search for ‘GE Talaria input panel’, you will see images.

Nifty

DeHavilland first flew a radio controlled aircraft in 1935, but they weren't American!

Nobody is talking about the special oil used. It was a well kept secret that it was WHALE OIL. Am I the only living being that knows that? The Telaria operator I knew is no longer with us.

@blackrockcity

9 ай бұрын

You gave me pause because anything is possible with this exotic technology, but I suspect the oil is very much synthetic or else it wouldn't hold up to years/ 1000's of hours of use. Someone here speculated that it was Polydimethylsiloxane.

I liked your video with a thumbs up even though it was number 666 lol