Ink jet pen with a heater element having a contoured surface

摘要

A thermal ink jet printhead (10) with a body (12) having an ink firing chamber (22) and an orifice (26). An electrically activated heating element (16) is connected to the body in thermal communication with the firing chamber, and includes a contoured surface portion coextensive with at least a portion of the heating element. The contoured surface portion of the firing chamber has a plurality of recesses (42).