How do implement the effect of blur on transparent materials? I'm trying to create a blur effect when a clear light passes through a transparent material. Here's a quick summary of the picture:



And when an object is close to a transparent material, it should be more visible than it is away from a transparent material. 

Here's a quick summary of the picture:



I've seen this tutorial for implement this, but I'm not trying to implement glass, because I'm trying to implement a protective film, so it doesn't fit my procedures.
A very simple solution is to create a render pass for the glass and use it as a mask to add blur in the compositor. Of course, to implement the depth effect, you would also then need to render out a depth mask to use as the blur amount, and then your passes are adding up. That's a lot of rendering and compositing just to avoid a glass material, but this method can sometimes end up rendering faster because it avoids some of the typical issues associated with rendering glass.