Ultrasonic end effectors with increased active length

An end effector for an ultrasonic surgical instrument, the end effector comprising:

• an ultrasonic blade, comprising:
• a first portion defining a first cross-sectional area and a first specific acoustic impedance;
• and
• a second portion defining a second cross-sectional area and a second specific acoustic impedance, wherein the second cross-sectional area is different than the first cross-sectional area, and wherein the second specific acoustic impedance is different than the first specific acoustic impedance.

An end effector for an ultrasonic surgical instrument, the end effector comprising:

• a first portion defining a first cross-sectional area and a first specific acoustic impedance;
• a second portion defining a second cross-sectional area and a second specific acoustic impedance, wherein the second cross-sectional area is different than the first cross-sectional area, and wherein the second specific acoustic impedance is different than the first specific acoustic impedance;
• and
• a third portion defining a third cross-sectional area and a third specific acoustic impedance, wherein the third cross-sectional area is different than the first cross-sectional area and the second cross-sectional area, and wherein the third specific acoustic impedance is different than the first specific acoustic impedance and the second specific acoustic impedance.