Disclosed is a circuit board (1) which is provided with a plurality of transistor elements, which are provided on the same insulating substrate (2) corresponding to two-dimensionally arranged pixels or a group of a predetermined number of the pixels. At least one of the transistor elements is an oxide TFT (10), which is provided with oxide semiconductor as a channel layer (11), and at least one other transistor element is an a-Si TFT (20), which is provided with, for instance, an amorphous silicon semiconductor as a channel layer (21). The oxide TFT (10) and the a-Si TFT (20) are both bottom-gate-type transistors.