Blu Ray vs DVD Player
There has been much ambiguity around this topic because transition has always been difficult for people. The storage of rich media content used to be an exclusive privilege and then VHS became popular to let you keep your favorite movie to watch again. It wasn’t that popular because using VHS was not that smooth. Then we were graced with CDs, and we had multiple CDs to keep a single movie with us and played them in CD players. Eventually, CDs were replaced by DVDs with higher capacity and we were able to store a complete movie in one DVD. Now we have Blue Ray Discs with even more capacity so that we can store a high resolution HD movie in a single disc. As you have seen, the evolution needed to happen because of the size restrictions. Let us talk about the mechanism of these two players so that you can understand the differences well.
What is the difference between Blu Ray Player and DVD Player?
• DVD is read by a red laser, which has a wavelength of 650nm, while Blue Ray discs are read by a Blue laser, as implied by the name having a wavelength of 405nm.
• DVDs have a capacity of 4.7GB in a single layered configuration and 8.7GB if it’s double layered. Blue Ray Discs, on the other hand, can have storage up to 25GB in a single layer and almost 50GB if it’s double layered.
• DVD Players can only play DVDs while Blue Ray Players can play both BR Discs and DVDs.
These two discs look identical and actually they are identical in physical design, as well. What differentiates them is the laser technology. The disc has grooves on the bottom layer which is used to store and read information. Since the DVDs use a red laser which has a lower wavelength, the grooves should have more space in between. That is why it can only store up to 4.7GB. In contrary, Blue Ray Discs use the blue laser with a shorter wavelength and thus, the grooves can be thinner and space in between is less than that of DVDs. In layman’s terms, we can focus the laser into a smaller square area in case of Blue Ray Discs while it’s not the case with DVDs which gives rise to the capacity differences in the storage. For this reason, BRD can stack more grooves and thus has more storage. Further, the protective layer in BRD is thinner than the DVD, but since it has more information, the layer makes it more scratch resistant than DVDs.