because we acoustically focus in the elevational direction the height direction and then we detect signal from the from this slice then we use image reconstruction to form a 2d image and if you want to get a third dimension of course you do the scan now this is a way the 1d array now if budget is not a problem then we can potentially get a 2d array I mean in the ideal world that you imagine we could surround the brass or the head with a lot of transducers in that case with a single laser shot you should be able to get a 3d image but