Transparent substrate with multilayer film and image display device

A transparent substrate with a multilayer film comprising:

• a transparent substrate having two main surfaces;
• and
• a multilayer film obtained by laminating at least two or more layers having refractive indices different from each other, and disposed on or above at least one main surface of the transparent substrate, wherein
• the multilayer film comprises
• one or more silicon oxide layers;
• one or more first metal oxide layers;
• and
• at least two second metal oxide layers,
• at least one layer of the one or more first metal oxide layers is sandwiched and laminated between two second metal oxide layers,
• the second metal oxide layers sandwiching the first metal oxide layer each have a film thickness of 8 nm or more,
• the one or more first metal oxide layers are each a layer being mainly formed of a mixed oxide comprising Mo and Nb and having an extinction coefficient k of 0.004 to 0.029 at a wavelength of 550 nm,
• the second metal oxide layers are each a layer being mainly formed of a mixed oxide comprising Mo and Nb and having an extinction coefficient k of 0.004 or less at the wavelength of 550 nm, and
• at least one layer of the one or more silicon oxide layers has a refractive index of 1.460≤n<1.478 at a wavelength of 550 nm.