Wavelength transformational structure as well as fabrication and usage thereof

The invention discloses a wavelength conversion structure, comprising a substrate and a wavelength conversion layer which is positioned on the substrate and comprises (a) a fluorescence powder which can be energized by UVc; and (b) a UVc-resistant adhesive agent, wherein, the thickness of the wavelength conversion coating is 2 to 10 times of the average grain size of the fluorescence powder and the content of the fluorescence powder in the wavelength conversion coating can satisfy at least one of the following requirements: (i) the volume percent of the fluorescence powder in the wavelength conversion coating is 30% to 85% (based on the overall volume of the fluorescence powder and the adhesive agents); and (ii) the weight ratio of the fluorescence powder and the adhesive agents is 1:1 to 20:1. The wavelength conversion coating can effectively convert UVc to visible light, thus, providing large-area light source of visible light.