Meh, you only need a little imagination to scan in 3D.
Instead of a disc, use a glass cylinder, mounted excentrically on an axis. (The actual glass cylinder doesn't even have to be excentric for this to work, because the data can be excentrically stored, but it's harder to explain. So assume it's a glass cylinder mounted excentrically on its axis.)
Spin the cylinder on its axis. For each revolution, move the laser one step along the axis. When the laser has reached the end of the cylinder, move the laser one stop closer to the spinning cylinder, then repeat the process in reverse.
The point of the excentricity is to get the "autofocus mechanism for free".
Search speeds could be a dog, but data density and durability could be insane. Plus it would look like something straight out of Star Trek. "Put the data crystal in there."
I think we misunderstand each other (and I've probably caused this confusion because I said CD 2.0). I think they are looking at reading whole 2D images at once, so not a point by point reading process.
Instead of a disc, use a glass cylinder, mounted excentrically on an axis. (The actual glass cylinder doesn't even have to be excentric for this to work, because the data can be excentrically stored, but it's harder to explain. So assume it's a glass cylinder mounted excentrically on its axis.)
Spin the cylinder on its axis. For each revolution, move the laser one step along the axis. When the laser has reached the end of the cylinder, move the laser one stop closer to the spinning cylinder, then repeat the process in reverse.
The point of the excentricity is to get the "autofocus mechanism for free".
Search speeds could be a dog, but data density and durability could be insane. Plus it would look like something straight out of Star Trek. "Put the data crystal in there."