Though I'd post this for anyone else in the same situation. Basically I accidently broke one of the lenses on one of my new Panasonic TY-EW3D3M glasses. Not wanting to waste a bunch of money on a new pair of glasses I decided to have a go at repair.
So I went on the hunt for another pair of Panasonic glasses with a damaged lense I could use. I found someone selling a pair o TY-ER3D4M glasses with a damaged lense for practically nothing. These glasses are exactly the same except they are RF instead IR.
Below are the steps I took to repair the glasses.
Starting with the damaged glasses.
1. First you need to remove the screws holding the 2 parts of the frames together, these are tiny screws so an appropriate cross point screwdriver is required. in total there are 7 screws to remove:
2. Once the screws are removed it's just a case of carefully separating the 2 halves of the frame, this is fairly easy but go carefully, the most difficult bit is where the nose piece is as there seems to be a couple of plastic studs that are glued which you can see in pic below. You just have to use a bit of force with the screwdriver to separate.
3. Next is to remove the lense. The first thing to do is to desolder the lens. The lens is soldered to the rest of the circuit by a ribbon cable.
It's just a case of desoldering the ribbon by melting the 2 solder points as seen in the pic.
Removing the lens can be done by pulling the frame at either side as the lens is held in with some little pieces of double sided rubber, then carefully pushing it out with the fingers.
4. To complete the repair it's just a case of doing the same with the other pair of glasses and swapping the lens then resoldering and reassembling. As a side note the lenses are identical either side, so it doesn't matter which lens is damaged as you can use either lens for repair.
The glasses are now working perfectly again. Hope this helps somebody else.