Light emitting device and lighting device having the same

A light-emitting device, comprising:

• a light-emitting element;
• and
• a light flux controlling member for controlling light emitted from the light-emitting element,
• the light flux controlling member having (i) a light-incoming surface from which the light emitted from the light-emitting element enters the light flux controlling member and (ii) a light-outgoing surface from which the light being incident on the light-incoming surface is emitted from the light flux controlling member, wherein
• the following equation (2) is satisfied:
• ∫
• P
• 
• (
• φ
• 1
• )
• 
• sin
• 
• 
• φ
• 1
• 
• 
• φ
• 1
• =
• -
• A
• 
• 
• 
• -
• r
• 2
• 2
• 
• σ
• 2
• +
• C
• (
• 2
• )
• where r is a length, from the reference light axis of the light-emitting device, of a plane that is provided at a certain distance from the light flux controlling member in a direction parallel to the reference light axis so as to be perpendicular to the reference light axis, φ1 is an angle between the light emitted from the light-emitting element and the light axis, P(φ1) is a light distribution property of the light-emitting element, C is a constant defined to satisfy φ1=0 when r=0, σ is a constant indicative of a scattering property, and A is obtained by the following equation (1):
• A
• =
• ∫
• 0
• π
• 2
• 
• P
• 
• (
• φ
• 1
• )
• 
• sin
• 
• 
• φ
• 1
• 
• 
• φ
• 1
• .
• (
• 1
• )