A photosensitive resin composition includes a positive photosensitive resin having a photosensitive moiety that cleaves upon exposure to light, and a wavelength conversion material dispersed in the photosensitive resin. The photosensitive resin and the wavelength conversion material meet (i) to (iv): (i) The photosensitive moiety and the cleavage product of the photosensitive resin do not neutralize the wavelength conversion material; (ii) The photosensitive moiety and the cleavage product do not induce hydrolysis of the wavelength conversion material; (iii) The HOMOs of the photosensitive moiety and the cleavage product are lower than the LUMO of the wavelength conversion material; and (iv) The LUMOs of the photosensitive moiety and the cleavage product are higher than the HOMO of the wavelength conversion material. (Any combination of a chemically amplified photosensitive resin with an acidic photosensitive moiety or cleavage product and an acidic wavelength conversion material is excluded.)

Provided is a wavelength conversion material composed of resin particles comprising an acrylic resin and an organic rare earth complex contained in the acrylic resin, in which deterioration of the organic rare earth complex is prevented. A wavelength conversion material composed of resin particles comprising an acrylic resin and an organic rare earth complex contained in the acrylic resin, wherein the acrylic resin is a polymer which is a reaction product of an acrylic resin composition comprising a (meth)acrylate monomer, a crosslinking agent and an azo polymerization initiator, wherein the acrylic resin composition is substantially free of an organic peroxide having a group represented by RC(O)O where R represents a hydrocarbon group that may be optionally substituted, as a polymerization initiator, and the acrylic resin composition comprises an organic peroxide having a one-minute half-life temperature of 145 C. or less as another polymerization initiator.

Proposed is a phosphor capable of effectively inhibiting the occurrence of adverse influence of a sulfur-based gas while improving water resistance of the phosphor and effectively inhibiting the corrosion of a metallic member. A phosphor is proposed, which includes particles or a layer provided on the surface of a sulfur-containing phosphor, which contains sulfur in a host material, and containing a crystalline metal borate containing an IIA-Group element, boron, and oxygen.

There is provided a metal-based particle assembly comprising 30 or more metal-based particles separated from each other and disposed in two dimensions, the metal-based particles having an average particle diameter in a range of from 200 to 1600 nm, an average height in a range of from 55 to 500 nm, and an aspect ratio, as defined by a ratio of the average particle diameter to the average height, in a range of from 1 to 8, wherein the metal-based particles are disposed such that an average distance between adjacent metal-based particles may be in a range of from 1 to 150 nm. This metal-based particle assembly presents significantly intense plasmon resonance and also allows plasmon resonance to have an effect over a range extended to a significantly large distance.

This solar cell module is provided with: a solar cell; a first protection member that is arranged on the light-receiving surface side of the solar cell; a second protection member that is arranged on the back surface side of the solar cell; and an encapsulant that seals the solar cell. The encapsulant comprises an encapsulant that is arranged between the solar cell and the first protection member and an encapsulant that is arranged between the solar cell and the second protection member, and the encapsulant contains a wavelength conversion substance. This solar cell module satisfies the condition of formula.

EQE(.sub.2)(10.46n.sup.2.8)EQE(.sub.1) formula

A solar cell module including: a solar cell; a first protection member provided on the light receiving surface side of the solar cell; a second protection member provided on the rear surface side of the solar cell; an encapsulant layer, including a first encapsulant layer disposed between the solar cell and the first protection member, and a second encapsulant layer disposed between the solar cell and the second protection member, which seals the solar cell; and a wavelength conversion substance, contained in at least the first encapsulant layer, which absorbs light having a specified wavelength, and converts the wavelength. The concentration of the wavelength conversion substance is higher in the first encapsulant layer than in the second encapsulant layer, and a resin constituting the second encapsulant layer has a smaller diffusion coefficient of the wavelength conversion substance than the diffusion coefficient of a resin constituting the first encapsulant layer.

A solar concentrator module (80) employs a luminescent concentrator material (82) between photovoltaic cells (86) having their charge-carrier separation junctions (90) parallel to front surfaces (88) of photovoltaic material 84 of the photovoltaic cells (86). Intercell areas (78) covered by the luminescent concentrator material (82) occupy from 2 to 50% of the total surface area of the solar concentrator modules (80). The luminescent concentrator material (82) preferably employs quantum dot heterostructures, and the photovoltaic cells (86) preferably employ low-cost high-efficiency photovoltaic materials (84), such as silicon-based photovoltaic materials.

There is provided an optical wavelength conversion element with a good temporal stability and such a high optical wavelength conversion efficiency that the element is viable even under sunlight or similar, low intensity light. Owing to these properties, the element is suited for use in solar cells, photocatalysts, photocatalytic hydrogen and oxygen generating devices, photon upconversion filters, and like articles. The optical wavelength conversion element is visually homogeneous and transparent and produced by dissolving and/or dispersing in an ionic liquid (C) a combination of organic photosensitizing molecules (A) and organic light-emitting molecules (B) that exhibits triplet-triplet annihilation. The organic photosensitizing molecules (A) have either an only one local maximum absorption wavelength or a plurality of local maximum absorption wavelengths, and either the single local maximum absorption wavelength or a maximum one of the plurality of local maximum absorption wavelengths is from 250 nm to 499 nm.

In some aspects, graphic layers for depicting a visible representation of an image along a surface of a photovoltaic module can include a plurality of substantially opaque isolated regions; and at least one substantially transparent contiguous region surrounding the substantially opaque isolated regions, wherein an outer surface of the at least one substantially transparent contiguous region comprises a matte surface finish.

The present invention includes upconversion materials such as lanthanide-sensitized oxides that are useful for converting low-energy photons into high-energy photons. Because silicon-based solar cells have an intrinsic optical band-gap of 1.1 eV, low-energy photons having a wavelength longer than 1100 nm, e.g., infrared photons, cannot be absorbed by the solar cell and used for photovoltaic energy conversion. Only those photons that have an energy equal to or greater than the solar cell's band gap, e.g., visible photons, can be absorbed and used for photovoltaic energy conversion. The oxides described herein transform photons having an energy less than the energy of a solar cell's band gap into photons having an energy equal to or greater than the energy of the band gap. When these oxides are incorporated into a solar cell, they provide more photons for photovoltaic energy conversion than otherwise would be available in their absence. Nearly 10% of the infrared photons incident on these oxides are upconverted into visible photons. This upconversion efficiency is more than twice as large as the upconversion efficiency for NaYF.sub.4-based upconversion materials. The solar radiation energy conversion efficiency of a silicon-based solar cell will increase by 1.8% or greater by including the oxides described herein because they allow the solar cell to absorb and use are larger portion of the solar spectrum for photovoltaic energy conversion.