Apparatus for measuring reflectance, method for measuring reflectance and method for manufacturing display panel

Can be efficiently obtained a reflection characteristic measurement device measuring reflection and scattering properties within the substrate plane. Reflectance measuring apparatus (100) of one embodiment of the present invention, comprising: as a substrate for mounting (101) to be measured in the stage (102); placed on the stage (102) the substrate (101) a first illumination light of an illumination source (103) and a second illumination source (105); and a first detector includes a light receiving element (104) and a second detector (106), said light receiving element from the first illumination source (103) and a second illumination source (105) illuminating the substrate was irradiated with light (101) reflected light; a first illumination source (103) substrate at any angle of illumination light (101) a second illumination source (105) irradiating light to the substrate in a ring (101).