add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
Use radio waves to read a CD conventional CDs would probably work. It wouldn't matter how scratched they were because the radio waves would go right through the plastic. The only problem might be less storage space.
Please log in.
If you're not logged in,
you can see what this page
looks like, but you will
not be able to add anything.
Annotation:
|
| |
light is a radio wave. But this wouldn't work. Inless I'm unaware of a way to focus a radio wave on a microscopic pit in plastic and detect the presence of aluminum, this won't work. |
|
| |
//I'm unaware of a way to focus a radio wave on a microscopic pit in plastic and detect the presence of aluminum// |
|
| |
Radio waves are much too long for this to work. For example, even a 1GHz radio wave is about 30cm (or a foot) long. |
|
| |
The optical laser used in a CD player has a wavelength of 780nm, or about 1/385,000 as large! - |
|
| |
Fishbone for bad physics. Light is an EM wave, but as [csea] states radio waves refer to a band from about 30cm to several kilometers. |
|
| |
Simple - just scale up the CD accordingly. Of course, then you'd have to just call it a D... |
|
| |
Ooh ooh ooh! How about an oil-
immersion CD player? The whole thing
runs in a bath of light mineral oil. The
refractive index will be closely matched to
that of the plastic outer layer of the CD,
and so scratches will be effectively
invisible. |
|
| |
What about turbulence created by the rotation of the disc ? |
|
| |
//What about turbulence// Shouldn't be a
problem optically if the oil is
homogeneous. Of course you'd need a
beefier motor to spin the CD, and probably
to move the head. |
|
| |
...and a way to keep the disc from floating around... |
|
| |
This thing would be a monstrosity of a Disk. maybe it should be calle an MD instead. Oh, and people could live in the pits, which would need to be dug with shovels. Maybe that's what that move "Holes" was really about. Certainly it wouldn't (or would) be far fetched to have the disk reader be in orbit around the disk and have the disk stand still, with the pits on the outer edge of the disk. |
|
| |
//oil- immersion CD player? // |
|
| |
Much better idea for the stated purpose, albeit a bit messy! [MB], can you find an appropriate oil? |
|
| |
Given the popularity of Drivesavers, etc for HD media, I suspect this could be a good business in the not-very-far-off-future (20x0s?) for reading "old" CDs. |
|
| |
What about using a Mexican wave? Or would that make everything sound like a mariachi band? |
|
| |
It is called oversampling, or Nyquist-Shannon Sampling. It erradicates noise, possibly introduced by scratches (in the case of optical media), or other noise. Harry Nyquist is not to be confused with Harry Renquist (an affible character portrayed by, the now, Governor of California). |
|
| |
radio waves destroy CDs, ever try putting a CD in a microwave? fun. |
|
| |
Appologies for any flippancy, but interleaving and oversampling work hand in glove to reduce reading/writing errors and associated noise. Although this is not oversampling's *priority* job. Oversampling's job, as I understand it, is to parse analog signals to digital bits. Its efficiency led to its use as a filter: |
|
| |
//The second method of output reconstruction deals with an oversampling digital filter prior to the DAC// ~ Dr. KM Buckley. |
|
| |
However, I stand for correction, as my investigation of this particular matter was a long time ago, with only a recent, rather truncated, revisit. |
|
| |
I object to be called a *complete* arse, many will attest to the fact that I am only an arse-part. |
|
| |