Has anybody here had a chance to work with these ultra short-throw video projectors? They all seem to follow the same design which is a regular lens followed with a curved mirror that enlarges the projection and shoots it back. https://www.youtube.com/results?sear...row+projectors
Panasonic has also made some "ultra short throw lenses" for their high power projectors with swappable lenses and by the looks of it it just contains the same type of mirror inside. https://www.youtube.com/watch?v=_nlo2X518lY
I'm curious what shape the mirror is and how it works if anyone knows. There are many DIY videos on youtube about making projections bigger by the use of a mirror but its just a regular flat mirror and all that does is increase the path length between the porjector and surface.
First I would like to know if there's anything different about the lenses which come before the curved mirror.
Second point of interest is the mirror itself. For DIY projects can anything like that be sourced from anywhere?
And why is there a mirror instead of extra lenses to begin with? I know and experienced that fisheye lenses at such extreme values produce quite an amount of chromatic aberration but as far as I know mirrors reflect different wavelengths at different angles as well, so what is the benefit of using a mirror which every company seems to be using?
PS. This is not for a laser related project but a hobby project using pico video projector plus accelerometer plus drone. Had good results with ordinary short throw pico projectors and fisheye lenses but need a bit wider projections still and with less chromatic aberration if possible so this is why I'm interested about these lens and mirrors inside the ultra short-throw projectors and what advantages it can have. So far only found a pico projector with such mirror by Sony but its not really that compact for my use case so probably need to mod one with my own mirror. I understand smaller picos are very dim for big projections but for my project it is enough if it is at least noticeable in pitch dark setting, don't need anything more than that.
This is slightly unusual offtopic discussion but many of you seem rather tech savvy in many areas so hope so will find interest in this thing I'm working on.