Blind and buried vias are used to connect between layers of a PCB where space is at a premium. A Blind Via connects an outer layer to one or more inner layers but does not go through the entire board. A Buried Via connects two or more inner layers but does not go through to an outer layer.
We do not use depth-controlled laser drilling to manufacture blind and buried vias. We first drill one or more cores and plate through the holes. Then we build and press the stack. This process can be repeated several times.