Most people who have dabbled in the world of electronic construction will be familiar in some form with the process of producing a printed circuit board by exposing a UV sensitive coating through a transparent mask, before moving on to etching. Older readers will have created their masks by hand with crêpe paper tape on acetate, while perhaps younger ones started by laser-printing from their CAD package.
How about a refinement of the process, one which does away with the acetate mask entirely? [Ionel Ciobanuc] may have the answer, in the form of an exposure through an LCD screen. The video below the break shows how it’s done, starting with a (probably a bit too lengthy) sequence on applying the photo-resist coating to the board, and then sitting LCD on top of UV lamp with the board positioned at the top of the pile.
It’s an interesting demonstration, and one that certainly removes a step in the process of PCB creation as it brings the pattern direct from computer to board without an intermediate. Whether or not it’s worth the expenditure on an LCD is up to you, after all a sheet of acetate is pretty cheap and if you already have a laser printer you’re good to go. We’re curious to know whether or not any plastic components in the LCD itself might be damaged by long-term exposure to intense UV light.
If you haven’t yet made a PCB using toner transfer, take a look at our handy guide.
Thanks [Setvir] for the tip.