Abstract: The spatial light intensity distribution and the total luminous flux of a LED airfield lighting lamp can be acquired by a Type-A goniophotometer. The uncertainty of measurement and the expanded uncertainty can be acquired through comparing the average light intensity of central beam and the true value. The average light intensity of central beam is acquired by moving the lamp along the horizontal direction and vertical direction, respectively. Results show that the expanded uncertainty of install location in the horizontal direction is less than that in the vertical direction. If the absolute value of relative error of average light intensity in central beam is asked to less than 2%, the expanded uncertainty in horizontal direction should be -0.3°~0.3°, and in vertical direction should be -0.4°~1°.

Key words: precision analysis, photometry, goniophotometer, LED airfield lighting