NOVELTY - A seal sheet comprises a fluorescent substance mixed into a sealing material (3) which protects a solar cell, where the fluorescent substance is, when an index of refraction of the sealing material is a and an index of refraction of the fluorescent substance is b, coated on its surface with polymer having an index of refraction c, the index of refraction of the polymer coating material is a that is less than c that is less than b.    USE - As seal sheet for solar cells (claimed) such as single crystal silicon solar cell, polycrystal silicon solar cell, thin-film compound semiconductor solar cell, amorphous silicon solar cell and various other solar cell elements.    ADVANTAGE - The sheet improves the efficiency of wavelength conversion film, and improves the photoelectric conversion efficiency of a solar cell. In the wavelength conversion material, a fluorescent substance whose surface is coated with polymer which emits green to near infrared light when excited by near ultraviolet to blue light is sealed. This reduces the quantity of light in sunlight which is not oriented toward the solar battery cell, thereby achieving high efficiency of wavelength conversion as well as improvement of the photoelectric conversion efficiency of the solar cell. Using the sheet, reflection caused by a wavelength conversion material is reduced, the quantity of light oriented towards the solar battery cell is increased, and the photoelectric conversion efficiency of the solar cell is improved. The solar cell module exhibits improved properties such as weathering resistance, high insulating properties and strength.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a solar cell module (1) having a structure in which a material containing a fluorescent substance is placed on a path of light to a solar cell, where the fluorescent substance is, when an index of refraction of the sealing material is a and an index of refraction of the fluorescent substance is b, coated on its surface with polymer having an index of refraction c, and the index of refraction of the polymer coating material is a that is less than c that is less than b.    DESCRIPTION OF DRAWING(S) - The figure shows schematic diagram of solar cell module when a wavelength conversion layer is formed between an antireflection coating and solar cell element.    Solar cell module (1)    Front glass (2)    Sealing material (3)    Solar battery cell (4)    Back sheet (5)    Antireflection coating (6)    Wavelength conversion material (7)    Wavelength conversion layer (8)