Description of Goniometer. A goniometer which can be used in making retro-reflection measurements in the CIE geometry is illustrated in Annex 1, figure 2. In this illustration, the photometer head is arbitrarily shown to be vertically above the source. The first axis is shown to be fixed and horizontal and is situated perpendicular to the observation half-plane. Any arrangement of the components which is equivalent to the one shown can be used.
Description of Goniometer. A goniometer as defined in paragraph 2.4. of this Regulation, which can be used in making retro-reflection measurements in the CIE geometry is illustrated in Figure A4-V. In this illustration, the photometer head (O) is arbitrarily shown to be vertically above the source (I). The first axis is shown to be fixed and horizontal and is situated perpendicular to the observation half-plane. Any arrangement of the components which is equivalent to the one shown can be used. Figure A4-I The CIE co-ordinate system Figure A4-I shows the CIE angular system for specifying and measuring retro-reflective device and marking materials. The first axis is perpendicular to the plane containing the observation axis and the illumination axis. The second axis is perpendicular both to the first axis and to the reference axis. Figure A4-II Goniometer mechanism embodying the CIE angular system 1: First Axis I: Illumination Axis α: Observation angle 2: Second Axis O: Observation Axis ß1, ß2: Entrance angles R: Reference Axis ε: Rotation angle P: Retro-reflective material Figure A4-II represents a Goniometer mechanism embodying the CIE angular system for specifying and measuring retro-reflective device and marking materials. All axes, angles, and directions of rotation are shown positive. Notes:
Description of Goniometer. A goniometer as defined in paragraph 2.3. of this Regulation, which can be used in making retro-reflection measurements in the CIE geometry is illustrated in Figure A4-II. In this illustration, the photometer head (O) is arbitrarily shown to be vertically above the source (I). The first axis is shown to be fixed and horizontal and is situated perpendicular to the observation half- plane. Any arrangement of the components which is equivalent to the one shown can be used. Part 2 - Description of the measurement geometry for measurement of the daytime colour and the luminance factor of retro- reflective material For testing the daytime colour and luminance factor of the material, illumination by CIE Standard Illuminant D65 (ISO 11664-2:2007(E)/CIE S 014-2/E:2006) using geometry (45a:0) shall be used.
Description of Goniometer. A goniometer as defined in paragraph 2.13. to this Horizontal Reference Document, which can be used in making retro-reflection measurements in the CIE geometry is illustrated in Annex 1, figure 2. In this illustration, the photometer head (O) is arbitrarily shown to be vertically above the source (I). The first axis is shown to be fixed and horizontal and is situated perpendicular to the observation half-plane. Any arrangement of the components which is equivalent to the one shown can be used. Figure 1 THE CIE CO-ORDINATE SYSTEM 1: First Axis I: Illumination Axis α: Observation angle 2: Second Axis O: Observation Axis ß1, ß2: Entrance angles R: Reference Axis ε: Rotation angle The CIE angular system for specifying and measuring retro-reflective marking materials. The first axis is perpendicular to the plane containing the observation axis and the illumination axis. The second axis is perpendicular both to the first axis and to the reference axis. All axes, angles, and directions of rotation are shown positive.
