Research participants:
B.W. Raaymakers,
J.J.W. Lagendijk, H. Kroeze,
A.N.T.J. Kotte We can calculate the SAR deposition due to a mobile phone very precisely. Figure 1 shows an example in which the measured SAR distribution in the Specific Antropmorphic Mannequin (SAM) head is compared with anatomically correct models of an adult an a child head, see Beard et al, 2006 for details.
Figure 1: The SAM head with phone model
Figure 2: Calculated SAR distributions a) SAM, b) Adult head, c) Child head
This knowledge can be applied to evaluate the safety guidelines for RF exposure due to mobile phones. A detailed anatomical model of the eye including discrete vasculature is constructed. This model can be used for thermal simulations. Figure 3 shows the normothermal distribution in the eye and the corresponding arterial blood tempertatures.
Figure 3: The anatomy and the normo-thermal temperature distribution of the human eye and orbit and the arterial vessel network with the colour-coded temperature distribution.
This high resolution eye model can be inserted in a lower resolution model of the entire head to combine the RF modelling of the head with the high resolution thermal modelling of the eye. In figure 4 the eye model is inserted in the head model by van Leeuwen et al. (1999). In figure 5 the SAR at 1500 Mhz for a 1 W antenna output at 5 cm in front of the eye is shown together with the corresponding temperature distribution calculated with the Discrete Vasculature (DIVA) model.
Figure 4: The high resolution eye model inserted in the head model by van Leeuwen et al. (1999), the black lines indicate the dipole antenna in front of the eye.
Figure 5: SAR distributon in the eye for 1W antenna output at 1500 Mhz. The SAR distribution in the entire head is shown in the left hand panel, the middle panel shows a zoom-in around the eye and the righ hand panel shows the temperature distribution as calculated with our Discrete Vasculature (DIVA) model.