If your advisor is not familiar with the research behind your project, how could he confirm that it is original and a contribution to the field? He must have had some prior knowledge of your project and your project must have been related to his research in some way.
I have been told that it is extremely rare to have any earth shattering contributions in a PhD dissertation, so kudos to you!
It wasn't earth-shattering, but it was sufficiently new that it qualified as "new knowledge." It was a new mathematical technique for separating a signal from noise. I recognized the need for it when I saw the shortcomings of the techniques in use in my work prior to going back to school. Unfortunately for me, it was soon superseded by even better techniques, so it sort of disappeared.