How to make an object transparent or invisible to light?

[shaili.dewangan (Shaili)]

I want the lights not to reflect on the outer layer of a bubble, but only impact (light up) the objects inside.

The render comes like this

How to make sure this doesn’t happen?

Here’s the blender file for reference:
businsbub_forum.blend (1.2 MB)

[goorman (Sergey)]

Hello,

Maybe something like this could help you:
new.blend (1.2 MB)

[MrTomas (Tomasz)]

try this:

and maybe in next step this

Cheers