NOVELTY - Making a multi-layer anti-reflective coating, comprises: preparing at least two un-solgel precursor compositions; depositing a first coating layer of one of un-solgel precursor compositions on a substrate; curing first coating layer by exposing the first coating layer to electromagnetic radiation; depositing at least one additional coating layer of one of the un-solgel precursor compositions on the first cured coating layer; curing the at least one additional coating layer by exposing the at least one additional coating layer to electromagnetic radiation; and heating the cured coating layers.    USE - The method is useful for making a multi-layer anti-reflective coating which is useful in: photovoltaic device (all claimed) including solar cells; windows (e.g. storefront windows); display cases; green house glass; solariums; and picture frames.    ADVANTAGE - The method provides multi-layer anti-reflective coating, which: increases the transmission of light through the substrate; and reduces reflection of solar light from the glass substrate, thus allows more solar light to pass through the incident glass substrate and reach the photovoltaic semiconductor so that the solar cell can be more efficient.    DETAILED DESCRIPTION - Making a multi-layer anti-reflective coating, comprises: preparing at least two un-solgel precursor compositions, where each of the at least two un-solgel precursor compositions comprises at least one inorganic oxide precursor and at least one UV curable monomer; depositing a first coating layer of one of the un-solgel precursor compositions on a substrate; curing the first coating layer by exposing the first coating layer to electromagnetic radiation; depositing at least one additional coating layer of one of the un-solgel precursor compositions on the first cured coating layer; curing the at least one additional coating layer by exposing the at least one additional coating layer to electromagnetic radiation; and heating the cured coating layers to form a multi-layer anti-reflective coating. INDEPENDENT CLAIMS are also included for:    (1) a multi-layer anti-reflective coated substrate, comprising: a substrate; and the multi-layer anti-reflective coating made by the above method;    (2) a photovoltaic device, comprising either: a photovoltaic layer; a glass substrate; and the multi-layer anti-reflective coating, where the glass substrate is provided on a light-incident side of the photovoltaic layer, and the multi-layer anti-reflective coating is provided on a light-incident side of the glass substrate; or a photovoltaic film; the glass substrate; and the multi-layer anti-reflective coating, where the glass substrate is provided on a light-incident side of the photovoltaic film; and    (3) a multi-layer anti-reflective coated substrate, comprising: the substrate; and the multi-layer anti-reflective coating made by: preparing a high refractive index un-solgel precursor composition comprising titania n-butoxide, a UV curable acrylic monomer mixture, acetic acid, and n-propanol; preparing a low refractive index un-solgel precursor composition comprising gamma -methacryloxypropyl trimethoxy silane and the UV curable acrylic monomer mixture; preparing a medium refractive index un-solgel precursor composition comprising the high refractive index titania un-solgel precursor composition and gamma -methacryloxypropyl trimethoxy silane; depositing the medium refractive index un-solgel precursor composition on a glass substrate to form a first coating layer; curing the first coating layer by exposing the first coating layer to electromagnetic radiation; depositing the high refractive index un-solgel precursor composition on the first coating layer to form a second coating layer; curing the second coating layer by exposing the second coating layer to electromagnetic radiation; depositing the low refractive index un-solgel precursor composition on the second coating layer to form a third coating layer; curing the third coating layer by exposing the second coating layer to electromagnetic radiation; and heating the cured coating layers to form a multi-layer anti-reflective coating.