I think all you need is a rough glass shader:

![enter image description here][1]


Or perhaps something like this:


![enter image description here][2]

Filtering out certain colors is a fairly simple matter:

![enter image description here][3]


  [1]: https://i.sstatic.net/0lPrT.png
  [2]: https://i.sstatic.net/GQx7u.png
  [3]: https://i.sstatic.net/NTo1h.png