Patent ID: 8368294

Claim:
A brightness improving structure of a light-emitting module with an optical thin-film surface layer, characterized in that said structure comprising: a transparent envelop shaped as a hollow sphere, a partial hollow sphere or a hollow body similar to a sphere and having a first wall and a second wall opposite to the first wall on the envelop, below the envelop or between the envelop and its internal center, said first wall having a first inside wall surface and a first outside wall surface, said second wall adjoining said first wall and having a second inside wall surface and a second outside wall surface; an optical thin-film which being a non-omni angular multiple layers film and having a long wave pass light filter function, and being coated on the first inside wall surface or the first outside wall surface of the transparent envelop over 30% of its area, said optical thin-film reflecting light rays at least comprising part or all ultraviolet or blue light exciting a fluorescent/phosphorescent layer and at least comprising visible light source which being in the long-wave band of visible wave length, and running through to emit; a light-emitting part shaped as a sphere, a spherical area or a partial sphere arranged in the transparent envelop so the transparent envelop and the light-emitting part being space-arranged for emitting ultraviolet or blue light by at least one ultraviolet or blue light-emitting diode, or a light-emitting tube or light-emitting electrodes provided in the light-emitting part; and a visible light layer formed of the fluorescent/phosphorescent layer, said visible light layer being coated on the second inside wall surface or the second outside wall surface the second wall surface of the transparent envelop for exciting the ultraviolet or blue light into visible light source, and the visible light layer being closer to the light-emitting part than to the optical thin-film; wherein the distance c between an any point A of the reflecting layer of arc of said optical thin-film and a center of sphere B of the light-emitting part should meet the following relationship: c≧cscα×r, wherein r being the radius of the light-emitting part, α being the incidence angle at the point A of the reflecting layer of said optical thin-film and a being 0 to 60°, a connection line of A and B being the normal of the reflection angle at point A, and b being the distance projecting to tangential point of the periphery circumference of the light-emitting part from the point A of the reflecting layer.