Patent attributes
An electronic injector including a needle insertion assembly configured to move a needle in an insertion direction from a first needle position where the needle is above the surface of a patient's skin to a second needle position where the needle pierces the patient's skin. The injector further includes a member mechanically coupled to the needle and configured to move when the needle. The injector further includes an optical detector having a generally planar detection surface and configured to detect movement of the member based on a change in a transverse projection of the member onto the detection surface and output a signal based on the change in the transverse projection. Additional, a processor is configured to determine the position of the needle based on the output signal, and the transverse projection of the member changes when the needle moves.
