PLANAR LIGHT-EMITTING DEVICE AND SHEET SWITCH MODULE

摘要

PROBLEM TO BE SOLVED: To provide a planar light-emitting device that can restrain light loss even with thinning of a light guide and sufficiently transmitting an amount of light in an objective direction.SOLUTION: The planar light-emitting device 1A includes a light source 2 wherein a light-emitting surface 2a is made of a light-transmitting material, and the sheetlike light guide 3 wherein one surface 3a is faced to the light source 2. At least a part of a surface of the light guide 3 opposite to the light source 2 is a lead-in zone 5 for introducing light from the light source 2. A scattering part 9 for scattering led-in light to the light guide 3 and turning it in a surface direction is formed on the lead-in zone 5 and/or an opposite surface side zone 7. A light-transmitting material of the light source 2 and the light guide 3 respectively have different refractive indexes. The light-emitting surface 2a of the light source 2 is adhered to the lead-in zone 5 of the light guide 3 through a light-transmitting adhesive material 14. A refractive index of the adhesive material 14 is in a range from a lower refractive index or more of either the light-transmitting material of the light source 2 or the light guide 3 to a higher refractive index or below of either.