Document ID: chunk:federal_register_of_legislation:F2024C00147:body:0:p43
Version: federal_register_of_legislation:F2024C00147
Segment Type: other
Provision Reference: 
Character Range: 152179–155093

Integrating sphere

Annex 7

Procedure for determining the radius of curvature "r" of the reflecting surface of a mirror

       1. Measurement

       1.1. Equipment

        A "spherometer" similar to the one described in Figure 1 of this annex having the indicated distances between the tracing pin of the dial gauge and the fixed legs of the bar is used.

       1.2. Measuring points

       1.2.1. The principal radii of curvature shall be measured at three points situated as close as possible to positions at one-third, one-half and two-thirds of the distance along the arc of the reflecting surface passing through the centre of this surface and parallel to segment b, or of the arc passing through the centre of the reflecting surface which is perpendicular to it if this arc is the longer.

       1.2.2. Where, owing to the size of the reflecting surface, it is impossible to obtain measurements in the directions defined in paragraph 2.1.1.6. of this Regulation, the Technical Services responsible for the tests may take measurements at the said point in two perpendicular directions as close as possible to those prescribed above.

       2. Calculation of the radius of curvature "r"

        "r" expressed in mm is calculated from the formula:

        Where:

        rp1 = the radius of curvature at the first measuring point,

        rp2 = the radius of curvature at the second measuring point,

        rp3 = the radius of curvature at the third measuring point.

Figure 1: Spherometer

Annex 8

Procedure for determining the "H" point and the actual torso angle for seating positions in motor vehicles[1]
Appendix 1 - Description of the three dimensional "H" point machine (3-D H machine)1

Appendix 2 - Three-dimensional reference system1

Appendix 3 - Reference data concerning seating positions1

Annex 9

  (Reserved)

Annex 10

Calculation of the detection distance

       1. Camera monitor device for indirect vision

       1.1. Determination of the smallest discernable detail

        The smallest discernable detail of the naked eye shall be defined according to standard ophthalmologic tests like the Landolt C test or the Triangle Orientation Discrimination (TOD) test. The smallest discernable detail at the centre of the viewing system can be determined using the Landolt C test or the TOD test. In the rest of the viewing area the smallest discernable detail may be estimated from the centrally determined smallest discernable detail and the local image deformation. For instance, in the case of a digital camera the smallest discernable detail at a given pixel location (in the monitor) scales inversely with the solid angle of the pixel.

       1.1.1. Landolt-C test

       In the Landolt-C test, test symbols are judged by the subject under test. In accordance with this test the smallest discernable detail is defined as the visual angle of the gap size of the