Some embodiments include an imaging system. The imaging system includes an active matrix pixel array having a flexible substrate and a pixel. The pixel includes a transistor over the flexible substrate, and the transistor includes multiple active layers having a first active layer and a second active layer over the first active layer. Further, the active matrix pixel array also includes a photodiode over the transistor, and the photodiode includes an N-type layer over the transistor, an I layer over the N-type layer, and a P-type layer over the I layer. Meanwhile, the imaging system also includes a flexible scintillator layer over the active matrix pixel array. Other embodiments of related systems and methods are also disclosed.