Id need to know a little more but I would suggest looking at a CIC CLG (Company Limited by Guarantee) in the first place.This is the same structure used by most Charities and is easily recognised as a not for profit, which organisations like the Arts Council prefer.
Get plaenty of advice before you make a decision, posting any questions onine is a good idea and im happy to arrange a telephone chat.
Once you've had a root through feel free to ask questions in the Forum (there is a setting up a CIC group that should be of interest) The paperwork isnt too bad, far better to make sure you have lots of good advice before you proceed.
The Foundation provides funding to projects in the UK that benefit the visually impaired. It funds work to assist and improve the treatment and education of the visually impaired. It also funds medical research and facilities for the treatment or alleviation of visual impairment.