Data is indeed read from the inner ring outwards, as anyone with a CD burner in the late '90’s and 2000’s is very familiar with.
For audio and video playback, the disk is spun faster at the beginning and progressively more slowly towards the outer edge, a process known as Constant Angular Velocity playback, because more linear distance is covered at the same RPM the larger your circle gets, i.e. the closer you are to the edge. This is no problem for audio playback at “1x” speed because this tops out at a paltry 500 RPM or so.
For data reads, however, most drives use Constant Linear Velocity and spin the disk at the same speed all the time. That means your data throughput is higher at the edges of the disk. The prevalence of 2x, 4x, 16x, 24x, 40x, 52x, etc. PC CD (and DVD, etc.) also means that those drives will spin a disk way faster than a regular CD player will which can definitely cause a problem with irregularly shaped disks like the one in OP’ photo. They would also inevitably only achieve their rated whatever-x speed when reading at the very edge of a full disk. (You mean the marketing department was deliberately misleading??? Say it ain’t so!)
Those little business card disks were nonstandard but would work in most tray loading drives, and held a whopping 30 megs.
It looks like it’s pretty balanced. The chin appears to be slightly further from the center than the hat to account for the extra weight of the ears. With how leverage works you don’t need much more weight to balance as long as it’s just a little further.
The tracking on the lasers for CDs is pretty crazy, since at those scales even well balanced CDs wobble like crazy. If it had to be super flat for it to work, each disc would be much too expensive. And as soon as it got dirty or warped in the sun, it wouldn’t work anymore. In reality CDs are pretty rugged and can take a lot of abusive before they can’t be easily read in even a cheap reader. It’s amazing technology really. It’s kinda crazy to think about how many holes per sec the laser can track and read for something like a blu-ray disc running at multiple times playback speed for data transfer.
I’m just guessing but it would be unbalanced as it spins in the disk reader, and probably wobble up and down making the laser inaccurate?
i think CDs spin faster - there were some business-card sizex CD ROMs back in the day. nb data is read from the inside out
Data is indeed read from the inner ring outwards, as anyone with a CD burner in the late '90’s and 2000’s is very familiar with.
For audio and video playback, the disk is spun faster at the beginning and progressively more slowly towards the outer edge, a process known as Constant Angular Velocity playback, because more linear distance is covered at the same RPM the larger your circle gets, i.e. the closer you are to the edge. This is no problem for audio playback at “1x” speed because this tops out at a paltry 500 RPM or so.
For data reads, however, most drives use Constant Linear Velocity and spin the disk at the same speed all the time. That means your data throughput is higher at the edges of the disk. The prevalence of 2x, 4x, 16x, 24x, 40x, 52x, etc. PC CD (and DVD, etc.) also means that those drives will spin a disk way faster than a regular CD player will which can definitely cause a problem with irregularly shaped disks like the one in OP’ photo. They would also inevitably only achieve their rated whatever-x speed when reading at the very edge of a full disk. (You mean the marketing department was deliberately misleading??? Say it ain’t so!)
Those little business card disks were nonstandard but would work in most tray loading drives, and held a whopping 30 megs.
It looks like it’s pretty balanced. The chin appears to be slightly further from the center than the hat to account for the extra weight of the ears. With how leverage works you don’t need much more weight to balance as long as it’s just a little further.
The tracking on the lasers for CDs is pretty crazy, since at those scales even well balanced CDs wobble like crazy. If it had to be super flat for it to work, each disc would be much too expensive. And as soon as it got dirty or warped in the sun, it wouldn’t work anymore. In reality CDs are pretty rugged and can take a lot of abusive before they can’t be easily read in even a cheap reader. It’s amazing technology really. It’s kinda crazy to think about how many holes per sec the laser can track and read for something like a blu-ray disc running at multiple times playback speed for data transfer.