Figure 1.
The terahertz spectroscopic properties for water and breast tissues.
(a) Refractive index and (b) absorption coefficient for water (blue full line), normal breast tissue (green dotted line), breast tissue containing tumour (red dot-dash line) and adipose tissue (grey dashed line).
Figure 2.
Simulation of liquid water using FDTD (full blue line) compared to measured water pulse (blue circles).
Figure 3.
Comparison of the simulated and measured THz data.
(a) Comparison of pulses for normal breast (simulated = green dotted line, measured = green dots), and breast tumour (simulated = red dot-dash line, measured = red crosses). (b) The differences between the measured and simulated pulses for normal breast (green dotted line) and tumour (red dot-dash line).
Figure 4.
Plots of real (ε’) and imaginary (ε’’) terms of permittivity values calculated from spectroscopy data for water (blue triangles), normal breast (green circles) and tumour breast tissue (red crosses).
(a) Shows the real versus imaginary permittivity, together with the best fit double Debye model determined from the least squares fitting method for water (full blue line), normal breast (green dotted line) and breast tumour (red dot-dash line), (b) Real terms of permittivity versus frequency and (c) Imaginary terms of permittivity versus frequency.
Table 1.
Double Debye values determined from the least squares fitting method.
Figure 5.
Change in the THz pulse parameter values as a function of the percentage of tumour.
The values for normal breast were used as the baseline and the changes in the parameters were calculated as a function of the proportion of tumour, showing measured breast tissue (black dots, black line) and FDTD simulated breast response (black open circles).
Table 2.
The 10 time domain and frequency domain THz parameters from Fitzgerald et al [15].