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beam angle

angle between two imaginary lines in a plane through the optical beam axis, such that these lines pass through the centre of the front face of the device and through points at which the luminous intensity is 50 % of the centre beam intensity

Note 1 to entry: The beam angle is a full angle measure, not a half angle measure.

Note 2 to entry: The beam angle is expressed in degree (°).

Publication date: 2020-12
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