Ventilation between flowering and vegetative rooms

I was wondering what the best way to provide circulation for a grow room with separate flowering and vegetative sections. I want to keep the light from vegetative section out of the flowering section while maintaining air flow. Is it best to have separate ventilation for each section or can I have air coming into one section and leaving the other?

Thanks in advance.

a tube with some bends will provide light from entering the flowering room but IMO I would use one for each room ..

light cant go round 2 bends in 4inch dryer tube