Loss Tangent or Dissipation Factor

In an ideal lossless dielectric material, there is a dephasage between the current and the voltage of 90°. By contrast, in the presence of dielectric losses, the dephasage is then equal to 90°-Sy and the power losses are proportional to tan which is called the loss tangent or dissipation factor. The angle by which the current is out of phase from ideal can be determined, and the tangent of 

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The extent to which a material is heated when subjected to microwave radiation depends on two parameters the dielectric constant e and the dielectric loss factor e". The dielectric constant describes the ease with which a material is polarized by an electric field, while fhe loss factor measures fhe efficiency wifh which the electromagnetic radiation is converted into heat. The ratio of these properties gives the dielectric loss tangent or dissipation factor ... 

The ratio e"/e is the amount of energy dissipated per cycle divided by the amount of energy stored per cycle and known as the dielectric loss tangent or dissipation factor (tan (5). 

As indicated earlier, those properties that govern whether a material may be successfully heated by a dielectric or microwave field are the dielectric properties the relative dielectric constant e, loss tangent or dissipation factor (tan S), and loss factor e". 

Tan 5 is also called the loss tangent or dissipation factor. Tan 5 is energy lost per cycle divided by energy stored per cycle (rms or peak values). 

Changing the polarity of the dipoles requires a finite amoimt of energy and time. The energy is dissipated as internal heat, quantified by a parameter called the loss tangent or dissipation factor. Further, dielectric materials are not perfect insulators. These phenomena may be modeled as a resistor in parallel with a capacitor. The loss tangent, as expected, is a strong function of the applied frequency, increasing as the frequency increases. 

The dielectric loss tangent or dissipation factor is a material property characterizing the loss behavior of the dielectrics itself. It is defined as follows ... 

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