Patent ID: 7067974
Filing Date: 2006-06-27
Classification: H01L,Y10T

Abstract:
1. A light-emitting apparatus comprising a substrate and a light-emitting device provided on the substrate, wherein the device includes a light-emitting layer located between a pair of electrodes, light generated by the light-emitting layer is emitted to the outside of the apparatus through the substrate, wherein a transparent member is provided on a side of the substrate opposite from the side where the light-emitting layer is provided, the transparent member having a face that faces away from the substrate and is an uneven surface having a plurality of asperities, the mean spacing Sm of adjacent asperities or the mean spacing S of peaks of adjacent projections of the asperities is no less than three times the longest wavelength of light generated by the light-emitting layer and no more than two hundred times the longest wavelength, wherein at least one of the following requirements (i)–(vi) is satisfied: (i) the arithmetic mean slope Δa of the uneven surface is in a range between 3° and 20°, inclusive; (ii) the root mean square slope Δq of the uneven surface is in a range between 4° and 25°; (iii) the ratio Ra/S of the arithmetic mean roughness Ra of the uneven surface to the mean spacing S of peaks is in a range between 0.01 and 0.07, inclusive; (iv) the ratio Ra/Sm of the arithmetic mean roughness Ra of the uneven surface to the mean spacing Sm of asperities is in a range between 0.004 and 0.035, inclusive; (v) the ratio Rz/S of the ten-point height of irregularities Rz of the uneven surface to the mean spacing S of peaks is in a range between 0.05 and 0.30, inclusive; and (vi) the ratio Rz/Sm of the ten-point height of irregularities Rz of the uneven surface to the mean spacing Sm of asperities is in a range between 0.025 and 0.14, inclusive.