Non-Contact Specific Electromagnetic Energy Dosimeter

Tech ID:

This invention is a method and apparatus for quantifying the electromagnetic energy absorbed by a surface. It uses the change of speed of an acoustic wave, caused by a temperature change in the surrounding medium, to quantify the electromagnetic energy absorbed at the surface.  It can be used to characterize the biologically significant Specific Absorption Rate (SAR), the electromagnetic energy dose absorbed by the human body.



Generation of radio frequency (RF) energy is a critical component of all communications equipment, such as cellular phones, radio towers, microwave towers, etc. However, exposure to this energy can have deleterious biological effects due to the increase in temperature resulting from its absorption.  Both the eyes and the testes are particularly susceptible to damage because of a lack of blood flow to dissipate the increased heat.  The Specific Absorption Rate (SAR) is the measure of the rate at which the human absorbs energy when exposed to a particular electromagnetic field.  The EPA has published standards for the safety of exposures at various SAR levels and the FCC has standards for the allowed RF output of devices.


Current SAR testing equipment requires a metal component to be in contact with the surface being analyzed to detect a temperature change. This contact can lead to distortion in the dosimetry measurement.  This novel dosimeter does not require contact with the surface, thus providing a more accurate SAR determination.  It correlates the change in speed of an acoustic wave through the surrounding medium, resulting from a change in temperature near the surface, to an electromagnetic energy dose absorbed.


Commercial Applications & Advantages:

This dosimeter can be used in variety of applications, from safety testing to medical equipment. It provides the following advantages:

  • Lower distortion and better accuracy in determining the Specific Absorption Rate (SAR)
  • Improved characterization of safe levels of exposure
For information contact:
John Fritz
Sr. Business Development Manager
Saher Maswadi
Randolph Glickman
Luisiana Cundin
Norman Barsalou
Shannon Voss
Patent Information:

United States - Utility

Patent No.11,415,456

Status: Pending