Materials Measurement Phil Bartley Shelley Begley

Loss Tangent''ε rε r'ε rεrκ"tanδ = ='ε κ '"r1tanδ = D = =QEnergy Lost per CycleEnergy Stored per CycleDDissipation FactorQQuality FactorAnother term will talk about is loss tangent. When complex permittivity is drawn as asimple vector diagram, the real and imaginary components are 90 o out of phase. Thevector sum forms an angle d with the real axis (e r ’). The relative “lossiness” of amaterial is the ratio of the energy lost to the energy stored.Here: tand = loss tangent = tan delta = tangent loss = dissipation factorIn some cases is used the term “quality factor or Q-factor” with respect to anelectronic microwave material.11