| 摘要 |
Light from light emitting element enters into a flux control member through a recess on an inner face of the light flux control member, being emitted from an emission control face (outer face). At least so far as light falls within a half-intensity-angular-range, the light satisfies Condition 1 (theta5/theta1)>1 except for light in the vicinity of a normal direction of the emission control face) and Condition 2 (Value of theta5/theta1>1 gets smaller gradually with increasing of theta1). It is noted that theta1, theta5 are angles made at being inner-incident to the emission control face and at being emitting from the same, respectively. The emission control face has a planar outline shape which is anisotropic around optical axis L, thereby causing value of theta5 /theta1 to have a change depending on direction angle phi around optical axis L, with the result that highly uniform light is supplied to a required anisotropic irradiation range.
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