Anyone seen this? The video looks pretty good. Light on details.
DIY HUD
As far as hiding it from other viewers, got me thinking about that 3m privacy screen I have. One side of the flexible type is glossier than the others.
In my simple tests, if the angle between the lcd is less than ~45, it displays perfectly. Some of the light still will still leak out to the window though. Though it looks less like a double image due to the composition of the material. Much more diffused.
If you rotate the material 90 degrees, there is no reflection (as it's meant to limit the light passing through it to a very narrow view angle, but it does obscure the view through it somewhat. More towards the bottom, but depending on how you locate it, it might be the front of the car itself you are occluding and nothing important.
I'll try and get some pics in a couple days.