Measuring procedure. Luminance measurements shall be made on a piece of clean white blotting paper with a minimum diffuse reflection factor of 70 per cent, having the same dimensions as the registration plate, placed in the position normally occupied by it and 2 mm in front of its holder. Luminance measurements shall be made perpendicular to the surface of the paper at the points shown in paragraph 5. of this annex, each point representing a circular area of 25 mm in diameter. For an illuminating device not equipped with filament lamps, the luminance values measured after one minute and after 30 minutes of operation shall comply with the minimum requirements. The luminance distribution after one minute of operation can Annex 6 be calculated from the luminance distribution after 30 minutes of operation, by applying at each test point the ratio of luminance values measured at one point after one minute and after 30 minutes of operation.
Appears in 2 contracts
Sources: Agreement Concerning the Adoption of Uniform Technical Prescriptions for Wheeled Vehicles, Agreement Concerning the Adoption of Uniform Technical Prescriptions for Wheeled Vehicles