Another hologram hoax?

holorefugee · Post by **holorefugee** » Thu Nov 11, 2010 11:58 pm

Is this a Pepper's ghost?

http://omgshots.com/735-amazingly-reali ... a-too.html

jsfisher · Post by **jsfisher** » Wed Nov 17, 2010 9:39 pm

It's just a projection on a large glass screen, no?

jnhong · Post by **jnhong** » Sat Nov 27, 2010 9:50 am

Yes, it's clearly Pepper's Ghost. The screen is readily apparent in the later parts of the video, attached to the supports on the sides. In fact, close up of Miku shows reflections of the people in front of the stage. There has to be a reflective screen for that to happen. But it seems the image is 3D, as the perspective changes when the camera moves around. Not sure how they do that.

The media calls it a hologram, but there's no conspiracy to hoax the public. You can write your indignation to the authors and tell them they're deeply uninformed and under-educated, but you might as well go to the beach and tell the tide to roll back.

Would be nice if we can develop real holograms that behave way better than this projected image. Let's put our efforts into that.

Joe

erose · Post by **erose** » Mon Dec 06, 2010 9:11 pm

I don't think you are seeing parallax as the camera move. The character herself is so animated that you can't help but see it as 3D.

John Klayer · Post by **John Klayer** » Mon Dec 27, 2010 12:20 am

http://www.telegraph.co.uk/technology/a ... splay.html

Dinesh · Post by **Dinesh** » Mon Dec 27, 2010 5:29 pm

Not actually new. Gabriel Lippmann used a similar technique in 1908 (?) of using multiple lenses. Each lens would capture the view from it's own perspective and, being a lens, would also capture image distance. When played "backwards, the lens function recreated both phase and distance measurements and the viewer saw 3D. The problem was that at the turn of the last century he could not find lenses small enough to show a convincing 3d image. Today with micro-lenses it's possible. The Apple patent is very similar, except the microlenses are embedded in the screen.

PinkysBrain · Post by **PinkysBrain** » Tue Dec 28, 2010 3:37 am

Just want to see credit where credit's due, Apple's patent for a reflective directional display is just a trivial variation of the ideas from earlier patents by Ray Alden (cited in Apple's patent but not referenced in the text of the patent). The inventive step is using reflective per pixel (or column) elements to distribute light to the viewer eyes instead of refractive, which is what mr. Alden had already conceived. The major advantage is that you can use front projection and you are freed from the limited viewing angles available with practical refractive lenses.

PS. the system is completely impractical for more than a couple of viewers though and the necessary spatial precision for projection seems to me hard in a front projection setup (for a single eye a pixel column has to be projected with a width of less than 1/100 the normal pixel width, and positioned with that same precision).