## 3 Results and Discussion
### Prototypes' Effectiveness in Reducing a Phone's Magnetic Field  
In order to determine the optimum distance that reduces phone radiation during phone conversations and phone standby mode, respectively, we will prepare three to four thicknesses or distances for the above three designs, respectively. After that, we will measure the phone radiation before and after using the prototypes during phone conversations and phone standby mode, respectively. Finally, we will input the radiation measured into the below equation to determine the three prototypes' effectiveness in reducing the phone's magnetic field. Equation of effectiveness in reducing a phone's magnetic field:  
\[\text{RDi}\%=\frac{\text{X}_{\text{i}}-\text{Y}_{\text{i}}}{\text{X}_{\text{i }}}\times 100\% \tag{1}\]  
where \(\text{X}_{\text{i}}\) is the magnetic field measured without the use of the prototypes, \(\text{Y}_{\text{i}}\) is the magnetic field measured with the use of prototypes, \(\text{RDi}\%\) is the percentage of the phone's radiation that has been reduced, and \(i\) is the prototype case. Figure 20 shows the experiment of measuring phone radiation when the prototype is installed on the phone under four conditions. RD1 presents the phone with the Prototype 1 case during an in-app phone conversation. RD2 presents the phone with the Prototype 2 case while Wi-Fi, data, GPS,  
Figure 19: Segmenting the grips in Prototype 3. Figure 17: Bottom grips removed in Prototype 3. Bluetooth, and Hotspot are on. RD3 presents the phone with the Prototype 3 case during an in-app phone conversation. RD4 presents the phone with the Prototype 3 case while Wi-Fi, data, GPS, Bluetooth, and Hotspot are on. Tables 1-4 show the percentage of the phone radiation reduced after using RD1 to RD4, respectively. In RD1 of Figure 20, the phone with Prototype 1 installed is measured during an in-app phone conversation while Wi-Fi is on. In RD2 of Figure 20, the phone with Prototype 2 installed is measured while Wi-Fi, data, GPS, Bluetooth, and Hotspot are on. In RD3 of Figure 20, the phone with Prototype 3 installed is measured during an in-app phone conversation while Wi-Fi is on. In RD4 of Figure 20, the phone with Prototype 3 installed is measured while Wi-Fi, data, GPS, Bluetooth, and Hotspot are on. As per the result shown, phone radiation is negatively related to distance. An increase in the distance away from the phone will lead to a decrease in magnetic field. This occurs in the results of Prototype 1, Prototype 2, and Prototype 3 and without installing any prototypes. The percentage of the phone's radiation is more reduced when the distance away from the phone is short, while the percentage of the phone's radiation is less reduced when the distance away from the phone increases. Let us take Table 5 as an example: using a 5 mm thick phone case reduces phone radiation by 57%, using a 10 mm thick phone case reduces phone radiation by 91%, using a 5 mm thick phone case reduces phone radiation by 57%, using a 15 mm thick phone case reduces phone radiation by 94%, and using a 20 mm thick phone case reduces phone radiation by 97%. To conclude, phone radiation is negatively related to the distance away from the phone, and it is more reduced when the distance away from the phone is short. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{\begin{tabular}{c} **Cover** \\ **Size** \\ \end{tabular} } & \begin{tabular}{c} **Magnetic Field (\(\mu\)T)—Without** \\ **Use of Prototype 1 (X1)** \\ **Mean** \\ \end{tabular} & \begin{tabular}{c} **Magnetic Field (\(\mu\)T)—Installed** \\ **(X1)** \\ **Standard** \\ **Deviation** \\ \end{tabular} & \
\begin{tabular}{c} **RD1\% of** \\ **Mean** \\ \end{tabular} &
\begin{tabular}{c} **RD1\% of** \\ **Phone** \\ **Deviation** \\ \end{tabular} \\ \hline
5 mm & & & N/A & N/A & N/A \\
10 mm & & 0 & 0 & 100\% \\
15 mm & & & 0 & 0 & 100\% \\
20 mm & & & 0 & 0 & 100\% \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Percentage of phone radiation reduced (RD1) after using Prototype 1 during an in-app phone conversation.