I had a long, unusually coherent, and unsettling dream wherein Seattle was hit by an extremely high-yield nuclear blast. It was very… well, unsettling.
Speaking of unsettling, I did not remember them making magnets this large (I mean, look at at that). Check out the supermagnets down below. For reference, have you ever played around with those rare earth magnets before? They look kind of like these, you can buy them at ThinkGeek. And they’re really really hard to take apart when they stick together. Yeah, well those are the lower quality ones. These are HIGH quality, and large enough to kill you dead. The force of impact between two magnets of this size would be enough to completely shatter both magnets, as well as probably send magnetized metal shards everywhere, injuring you. Walk through an area with metal things in it, even ten feet away, and if you’re carrying one of these magnets they will fly off the table and break your bones.
I wonder how they took those pictures? It’d be hard to do without damaging the camera.
Last time I remember looking at United Nuclear, they wouldn’t sell magnets approaching that size unless you had a research grant, because they were afraid of lawsuits in the likely event of grievous injury. Evidently that’s all been ironed out now, because anyone harboring two or three hundred bucks and the irrepressible desire to be in the possession of a life-threatening magnet can acquire one.
That said, I would just LOVE to someday make a cube magnet six inches on a side out of the 2x2x3″ block magnet. The equipment necessary to assemble the dang thing would be expensive, the process of actually doing it would be incredibly difficult, the 18 component magnets themselves cost $175 each plus whatever large shipping and handling costs they levy, but the resulting object would be a solid-state, everlasting, lurking menace worthy of anyone who’s taken over the world. You could just mount it in the center of a large, empty room, and… have ceremonies in there, or just play around or something.
Flixxy is a pretty neat site. From what I can tell, they just link to videos that are really cool, eliminating much of the dross from YouTube and several other prominent video sites. Many, many fascinating things can be found just by browsing around inside. Not only that, but they eliminate video comments and channel subscriptions, which I am all for. I mean, they don’t actually host the videos themselves anyway, so I guess it makes sense.
In the field of holographic displays, various research projects have popped up the past five years or so. One particular Scientific American article introduced several, one involving projecting an image onto a spinning disc, one involving a screen with two images interlaced vertically and a thinly barred screen (like a diffraction grating only larger) revealing each image to only one eye. Another actually projected frames onto multiple screen surfaces at different depths, which when used together create a very realistic impression of a smooth 3d image. The interlaced screen is little more than a very complicated system so that you don’t need to actually wear 2-screen googles (it did require head-tracking). The other two appeal to my sense of completeness better, especially the spinning disc one.
There are basically three categories that I can think of for 3d displays.
The first merely displays different images to each eye, like with old-school 3d goggles, the interlaced screen, and the one method that will eventually win for efficiency, awesomeness, and quality in personal display devices: retinal laser projection, which excites me particularly.
The second category traces light patterns into the air, unfortunately on a moving surface or some substrate; holographic projectors like you see in sci-fi movies barely have any practical implementation at all. The advantage and disadvantage of this method is that while it is tracing a true 3d image in the air, visible from every angle you can get a vantage point from, projected images don’t occlude anything behind them; that is, they don’t appear to be solid, you can see right through them. This means that you can see the internal workings of devices if they’re shown, but this method would not be suitable for showing three-dimensional movies.
The third category projects a different image at every angle. From what I’ve seen so far, it’s only practical to do this in a horizontal fashion, so that the image does not change when viewed higher or lower, only distorts some. With camera- or head-mounted tracking, you can in fact make it appear correctly when viewed from closer to above it, but that doesn’t really matter usually. It works great, because as you can see, projected objects appear to be occluded.
Another, more interesting and by all indications undemonstrated category of device (which I shall refer to as category 3a) would be a SURFACE that appears different from every angle. Such a device, if made practical, could be made into something the size and shape of modern LCD monitors. The key would probably lie in making microscopic projectors and lenses less than a quarter of a millimeter square on the end, then forming them into a gigantic array ten, twelve, thirty inches in diagonal. Such a device could be used as a regular flat boring 2d monitor for normal applications, then periodically switch to a deep, near-realistic window into another world. Like the Wizard of Oz, seeing such a transition would be no less breathtaking than a transition from washed out sepia to full, vibrant color.
Category 3a devices needn’t be flat, though. You could also form them into a cylinder, or perhaps a sphere, for full 360° viewing pleasure.
When you consider the big picture, the first and third categories will probably endure for a long time, while the second is slightly more limited in its practical uses. The more information you display, the harder it is to make out. For practical purposes, the category 3 devices can be made to do everything category 2 devices can do, with a little more computational work involved.
It occurs to me I should consider lasting practicality. Category 1 devices are of course already plenty practical; categories 2 and 3 may win or lose based on the necessary size of the device itself. Both kinds could hurt you if you touched them, since they’re spinning so fast. The real issue of size lies in the ability to project onto the device from below. This is a simple matter with category 2 devices, but with the spinning mirror in a category 3 device this is a more difficult proposition. The bulkier projection equipment in the demo I linked to is actually mounted above the mirror itself, making the design large and impractical for home use. If you inverted the mirror, then, you could easily project from the bottom, but it would only be viewable from so high up. Angling the mirror nearer the vertical would help too, but this would result in a wider base. So all things considered, spinning-mirror model category 3 devices need some revision in form to be ready for home application, but should be sufficient once that is accomplished.
With all that said, I’m still waiting for the vast improvements needed in the color selections and brightness/contrast of modern 2d display monitors – namely, exponent-curved 48 bit brightness levels and 4 or 5 frequency displays to more accurately represent actual vision. Until they get that right, 3d displays should stay in museums.
Edit: More specific information on retinal laser displays. There’s a few other articles as well on in-depth design, which I can’t seem to find because I read them in some magazine in Canada, and can’t find them again.
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