Hadn't had to much time to experiment lately ,i gave it a run last week no results so back to the optics and light sensor side of things .
So going to go back to basics and see what results i can detect doing all this nice and slow i figure its in a way not to different to a reflective opto sensor off a encoders light and dark areas ...signal no signal or in this case we have shades all between the two .
I tried this tonight in the photos to track down fault find my problems...perhaps not the best of slides to use but has a bit of of light and dark areas to sweep across the light sensors light hole .
Problems i have found ......
The frame mirror as it moves rocks down the light line from the polygon also moves down so i would only have the thickness of the polygons mirror before the light line is lost below the light sensors light hole .
I was not expecting this boy am i bad at optics
Seems a vertical slit instead of a hole might fix this .
ON the head amp working I can just hear the sensor picking up the light differences as i sweep this line of the image across it, its still very much so in the snow or white noise so if it did work at that light level it would be a snowy image.
So making this little slide projector with that light level which i suppose would be better than day light ? it still would not be good enough .
With more light say using a projector doing the same sort of thing could improve things.
Now what i have seen tonight i have a bit of a problem as is now as the frame mirror rocks and projects a light line to the polygon and the polygon to the light sensor area the light line moves down out of the light sensor hole area .......i was thinking a slit mask would fix this as the solar cells surface area is large but the polygons light would not be a tiny square but a longer rectangle ( . l )instead of that dot i would see that line in the bracket which would end up being a fair few lines thick .
Speculating masking of part of the polygons mirror to a slit or just another mask horizontal mask ....I sure have a bit of thinking.
May be i have the frame mirror sitting at the wrong angle ? as its sitting now if i have it vertical to start with perhaps the light line will stay reflected to the same place even with angle change .
If i ever get this working she will be a keeper ...

The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.