Directional Dependence of Gafchromic LD-V1.

Gafchromic LD-V1 (LD-V1) is a highly sensitive radiochromic film used as a radiation measurement technique that can be applied to the surface of an object because of its flexibility. However, if radiation is incident on the film from an angle other than perpendicular, the film's sensitivity may change depending on the angle of incidence. In this study, we investigated the directional dependence of LD-V1 on the surface of an acrylic phantom. The relative sensitivity at the angle of perpendicular incidence of X-rays on the film was 54.5%, while the relative sensitivity at other angles exceeded 90%. The LD-V1 can perform measurements at angles other than perpendicular X-ray incidence.