## 4 Discussion  
The edgeless array demonstrated excellent linearity in dose response across a dose range of 50 to 500 cGy at 6 MV, yielding R\({}^{2}\) = 1. The average sensitivity throughout the array was 6.95 \(\times\) 10\({}^{-3}\)\(\pm\) 2.3 \(\times\) 10\({}^{-5}\) Gy/nC, indicating a reproducibility of 0.33%. The reproducibility of the sensitivity between the two different LINACs and hospitals was measured to be 3.6%. The sensitivity recorded in this work is much smaller compared with that in previous works [31] using the same edgeless diode architecture but with a smaller sensitive area (0.5 \(\times\) 0.5 mm\({}^{2}\)), which is reported to be approximately 15.29 \(\pm\) 0.01 nC/Gy (6.5 \(\times\) 10\({}^{-2}\)\(\pm\) 4.78 \(\times\) 10\({}^{-5}\) Gy/nC). The edgeless array is also more sensitive to ionizing radiation compared to commercial grade devices such as SRS MapCHECK [45], being n-type diodes with a sensitivity of approximately 15 nC/Gy (6.67 \(\times\) 10\({}^{-2}\) Gy/nC). Percentage depth doses for a 10 \(\times\) 10 cm\({}^{2}\) field at 6 MV are closely matched with reference IC measurements within a 1.8% margin, spanning from d\({}_{\text{max}}\) = 1.5 cm to a depth of 25 cm. This consistency is in line with earlier findings for PP edgeless diodes, which exhibited agreement with ionization chamber measurements within \(\pm\)2% beyond the build-up region [31]. However, a slight systematic under-response is observed at greater depths in Figure 5. This discrepancy may be attributed to the uncorrected dose DPP dependence. As discussed in relation to Figure 8, the edgeless diode displays reduced relative sensitivity at lower DPP. Consequently, as the DPP gradually decreases at greater depths due to attenuation and the inverse square law, the PDD exhibits a large decrease compared to an IC, as the PDD is normalized to a reading at a higher DPP. This phenomenon is well-recognized for causing discrepancies in PDD curves on the order of a few percent [38]. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Detector** & **Methodology** & **Angular Response** & **Reference** \\ \hline Edgeless & Coplanar, 0\({}^{\circ}\) to 180\({}^{\circ}\) & \(-\)4\% at 90\({}^{\circ}\) & This study \\ \hline  & Coplanar, \(-\)175\({}^{\circ}\) to 180\({}^{\circ}\) & & \\  & 6 MV FF, 5 \(\times\) 5 cm\({}^{2}\) & \(\pm\)8\% (\(\pm\)2\%) & [42] \\ \cline{2-4}  & Non-coplanar, 0\({}^{\circ}\) to 180\({}^{\circ}\) & \(\pm\)8\% (\(\pm\)4\%, \(-\)8\% at 90\({}^{\circ}\)) & \\ \cline{2-4}  & Coplanar, full 360\({}^{\circ}\) range & \(\pm\)8\% (\(\pm\)2\%, \(-\)8\% at 90\({}^{\circ}\)) & [22] \\  & 6 MV FF, 5 \(\times\) 5 cm\({}^{2}\) & \(\pm\)8\% (\(-\)3.5\%) & \\ \hline  & Coplanar, 0\({}^{\circ}\) to 180\({}^{\circ}\) & \(\pm\)5\% & [43] \\ \cline{2-4} Octavius 1000 SRS & Coplanar, 0\({}^{\circ}\) to 90\({}^{\circ}\) & \(\pm\)5\%, \(>\)10\% above 80\({}^{\circ}\) & [44] \\  & CyberKnife, 60 mm cone & & \\ \hline  & Coplanar, 0\({}^{\circ}\) to 180\({}^{\circ}\) & 4.34\% & \\  & 6 MV FF, 2 \(\times\) 2 cm\({}^{2}\) & 8.45\% & [24] \\ \cline{2-4}  & Non-coplanar, 2 \(\times\) 2 cm\({}^{2}\) & \(-\)38\% & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: A comparison of the angular dependence of the edgeless array with directional responses measured in commercial 2D arrays. The methodology specifies whether the beam was coplanar (couch angle equals 0) or non-coplanar (couch angle not equal to zero), along with the measured angular range, beam energy, and field size utilized. Angular responses are presented as either the maximum deviation or upper/lower bounds within the angular range. For MapCHECK, values in brackets indicate results after corrections are applied. The EPOM for the central diode was found to be 0.79 \(\pm\) 0.05 mm downstream from the reference depth. The depth of the EPOM significantly relies on the construction of the detector and the measurement geometry.