| 摘要 |
A lighting device (100) has a light-emitting element (120) positioned on a substrate (110), and a light beam control member (130) that reflects some of the light emitted by the light-emitting element (120), and allows some of the light to pass through. The light beam control member (130) has a reflective surface (132) that faces the light-emitting element (120), and reflects some of the light emitted by the light-emitting element (120). The reflective surface (132) has an aspherical curved surface, the height of which increases from the light-emitting element (120) toward the outer periphery from the center. The reflective surface (132) reflects light in a lateral direction in a region at the center, and reflects light in a backward direction in a region at the outer periphery. |
| 主权项 |
1. An illumination apparatus comprising:
one or more light emitting elements disposed on a substrate; and a light flux controlling member that is positioned relative to the light emitting element with air space in between such that an optical axis of the light emitting element and a central axis thereof coincide with each other, reflects part of light emitted from the light emitting element and transmits part of the light, wherein the light flux controlling member has a reflection surface that faces the light emitting element and reflects part of the light emitted from the light emitting element, the reflection surface has an aspherical curved surface whose height from the light emitting element increases toward an outer peripheral portion from a center portion, which center portion is an intersection with the optical axis of the light emitting element, the outer peripheral portion of the reflection surface is formed at a point distant from the light emitting element in a direction of the optical axis of the light emitting element, as compared with a position of the center portion of the reflection surface, and the reflection surface reflects part of the light emitted from the light emitting element so as to satisfy following Expression 1 when an angle of the light emitted along the optical axis of the light emitting element from the light emitting element is assumed to be 0°:
θ(a2)<θ(b2) (1) where θ(a2) is an angle of light with respect to the optical axis of the light emitting element, where the light is emitted from a luminescence center of the light emitting element at an angle of θ(a1) with respect to the optical axis of the light emitting element and reflected by the reflection surface; θ(b2) is an angle of light with respect to the optical axis of the light emitting element, where the light is emitted from the luminescence center of the light emitting element at an angle of θ(b 1) with respect to the optical axis of the light emitting element and reflected by the reflection surface; and θ(c1)≦θ(a1)<θ(b1) is established when an angle of a line with respect to the optical axis of the light emitting element is assumed to be θ(c1), where the line connects the luminescence center of the light emitting element with a point at which light arrives on the reflection surface, the light being emitted in a direction parallel to the optical axis of the light emitting element from a furthest point from the luminescence center of the light emitting element in the light emitting element. |
