Maybe sharing this idea after building a prototype would be much better.
As many of you know, there is a technique to make a PCB with laser CNC. You spray a matte black paint onto PCB, and burn that paint at some points to create tracks.
The problem is that me, and I am sure, many other people doesn't have laser engraver. Either too expensive to buy one, or building a quality one at home is not that easy. This entry is about easing this process, and making it very cheap. My proposed method is as follows:
- Cut a PCB at the size of a DVD. Inner hole should be cut as well.
- Spray the PCB with black matter paint.
- Put the PCB into DVD writer.
- Start the DVD writer program that reads what to be written onto DVD (PCB) from gerber file.
- Laser of DVD burns each bit on DVD that removes paint from there.
- Take out the DVD (PCB). Etch it with chemicals.
Actually, to be able to understand this procedure, one needs to use his imagination. Above idea came to me 5 minutes ago. So, it is not perfect maybe.
Please check this picture first: http://en.wikipedia.org/wiki/DVD#mediaviewer/File:Comparison_CD_DVD_HDDVD_BD.svg
In this procedure, problems are as follows:
1. Minimum diameter of a point a DVD writer can focus is 400nm.
2. There is 420nm distance between top and bottom points.
3. Fume of burning paint cannot escape from DVD writer while it is already being burned.
4. Inner circles of DVD has less sectors than outer ones. Conversion from gerber file (e.g. black-white image) to bits on sectors can be hard.
I know this as less like a question, but a blog post, though has anyone experienced doing anything like this? I don't have enough big PCB and spray paint right now unfortunately.
Question is that is there anyway to modify DVD writer's head moving mechanism to remove that 420nm space, so that it can draw a seamless track?
Best Answer
Sorry, teak, but no go. Chris Stratton hit the weak spot. Even blank writable CDs/DVDs have a series of readable bits already on the disk. This establishes what is called the data spiral. If you cover this up, the electronics will have no way to sync up to the disk position.
On a related note, your idea is actually something close to LightScribe, http://en.wikipedia.org/wiki/LightScribe but as far as I can tell not close enough.