| 摘要 |
PROBLEM TO BE SOLVED: To optimize and improve light extraction efficiency, thereby improving a change in chromaticity by a view angle.SOLUTION: A luminaire 10 has a light extraction member 7 provided with a light deflection element 5 laminated on a light radiation surface of an EL element 101. The light deflection element 5 is formed by arranging a large number of minute convex portions 5a closely on the light radiation surface. The convex portions 5a have a convex surface in a longitudinal section view, where a height shape at a displacement x in the width direction on the convex surface can be expressed by an irregular function f(x). Letting a difference between the maximum and the minimum values of the function f(x) be &Dgr;f(x), then 0.001 mm≤&Dgr;f(x)≤0.300 mm is satisfied. Assuming that a function derived by extracting an inflection point in the function f(x) is g(x), an average inclination rate in absolute value |dg(x)/dx|of inclination between two adjacent points in the function g(x) satisfies the expression 1≤|dg(x)/dx|≤8. |
