Question: Can I use a DVD or does it have to be a DVD-R ?

Hi, thanks. I read through this article, it implies that any DVD could be used, assuming it is splitable. But it doesn't specifically state if there is some property of DVD-R that a DVD (non -R) doesn't have.

My question is better phrased, is there some property that a DVD doesn't have that makes it unsuitable.

I split two DVD's I had, and they separated awesomely, the aluminum was on the top, the bottom was relatively clean of aluminum.

However, the bottom was not purple, like the one I got in my kit. So that is why I started looking at using some old DVD's I had.

I'm gonna have to go get some DVD-R if that is a specific requirement.

I see below that someone said a CD could be used, and it might have better line width. So I have a lot of old CDs. As long as they are splitable, do you all know if they would then be usable, assuming the aluminum sperates as needed.

Thanks in advance, looking forward to this project.

Tried to edit my answer. I meant that since my split DVD bottoms didn't have purple, I was concerned they were not usable.

i got lucky on two ol DVD's, they split much easier than the DVD-R I got. I'm just concerned they would not be usable because of some other property, as I mentioned in my long reply above. Thanks for the answer.

Just to be clear, If I can effectively split a CD, and get a clear bottom, it is totally usable. I see you are saying that, clearly, but want to be extra careful. Thanks for the answer.

I'm really puzzled as to where you are getting CDs and DVDs you can split. As far as I know all commercial pressed CDs are single layer and so are DVDs. The clear polycarbonate is moulded into a disk with the pits and lands that represent the information. It is vacuum flashed with a reflective aluminium layer and then spin coated with a clear lacquer. One single disk of moulded plastic with two coatings - nothing to split. And my article on preparing the diffraction grating specifically says DVD-R in the title and throughout. I just don't see the ambiguity.

I split a software DVD and was able to get spectra from it. I asked because I had a question, and the question was, if a regular DVD would produce a spectra.

The picture I will post below as an answer indicates that, at least for the regular DVD I had, I could split and get a spectra.

It occurred to me that the DVD I have been using may have been a DVD-R that was burned and published as a DVD. That may explain why It was so easy for me to split my DVD, but there was no purple.