Document ID: chunk:federal_register_of_legislation:F2024C00148:reg:1:p26
Version: federal_register_of_legislation:F2024C00148
Segment Type: reg
Provision Reference: reg 1 (pt 26/34)
Character Range: 206452–209431

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[15]
 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 for CMS of Classes V and VI
              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 Landolt C symbol at threshold size and is expressed in arcmin. The threshold size corresponds to the size at which the subject judges the orientation correctly in 75 per cent of the trials. The smallest discernable detail is determined in a test involving a human observer. A test chart containing test symbols is placed in front of the camera and the observer judges the orientation of test symbols from the monitor. From the threshold gap size of the Landolt C test symbol d [m] and the distance between the test pattern and the camera D [m] the smallest discernable detail ωc [arcmin] is calculated as follows:

              1.1.2. TOD test

              The Landolt C test can be used to determine the smallest discernable detail of the camera-monitor system. However, for sensor systems it is more suitable to use the TOD (Triangle Orientation Discrimination) method which is similar to the Landolt C method, but involves equilateral triangular test patterns. The Triangle Orientation Discrimination method is described in detail by Bijl & Valeton (1999), who provide practical guidelines on how to perform a TOD measurement. In the method, triangular test patterns (see Figure