Why CD devices can not read DVD?

Answer 1

I'm not an engineer, but while lasers are used to read both CD's and DVD's, the required laser is different. I suppose it is due to the frequency that the laser is reading. Anyway, DVD's are about 3 times tighter packed than CD's, so the CD's laser can't focus in on the data. This is why if you tried to store a movie on CD (using the CD-i format, for example), you would end up with 3 or 4 CD's compared to one DVD.

Answer 2

Data on CDs and DVDs is written in rings, much like the grooves on an old phonograph record. The rings on a DVD are much narrower than the ones on the CD, so the laser in a CD drive can't read them.

Answer 3

A DVD disc uses a different wavelength and the laser is thinner than a CD drive one making it incompatible with current CD drives as their lasers cannot read the information on them. Although you can read a CD on a DVD-ROM drive because they are backward compatible.

Answer 4

There are a number of possible reasons for a DVD not to play on a DVD player. In an effort to reduce piracy, DVDs and DVD players are designed for a group of large geographical zones, and a DVD intended for the European zone will not play on an American DVD player. Aside from that, the DVD could be damaged, or the DVD player could be damaged. Or not plugged in.

Answer 5

DVD drives can only read DVDs not CDs because of the way they are programmed. It is supposed to read DVDs which is why it is not used to reading CDs.