In neutron imaging, enhancing the brightness of a neutron detector is an important factor for shortening the imaging time and improving the image quality. Recently, we devised a technique for increasing the light intensity received on a camera by adding brightness enhancement films (BEFs) on the output surface of a scintillator. Using a BEF (BEF II 90/24, Vikuiti 3M), the brightness was enhanced, but the spatial resolution was reduced. In this study, we investigated the brightness and spatial resolution using several types of BEFs with different thicknesses and prism pitches. No correlation between the brightness and the film thickness, and between the brightness and the prism pitch, was recognized. For the spatial resolution, however, when the film thickness was reduced, the spatial resolution was observed to improve.