4.8 Heading marker indication
When inside the field of view, the graphical ahead mark of the craft should be indicated on the display with a minimum error not greater than +/- 1 degree.
When outside the field of view a visual indication of relative bearing with a maximum error of +/- 1 degree should be provided.
4.9 Roll or pitch
The performance requirements in this standard should be achieved under the roll and pitch conditions experienced in high speed craft.
4.10 Clear view
Arrangement should be provided to ensure cleaning of the sensor head/lens from the operating position.
4.11 Optical interference
Measures should be taken, that the surroundings of objects commonly encountered at sea and in ports should not be displayed less clearly on the monitor of the night vision equipment because of dazzle effects, reflection, blooming, or any other effects.
4.12 MALFUNCTIONS, WARNINGS, ALARMS, AND INDICATIONS
Night vision equipment should have the following displays
state of operation;
visual alarm in the event of failure of the night vision equipment;
4.13 Software requirements
If certain functions of night vision equipment are implemented using software, such software should meet the applicable requirements of IEC 60945.
4.15 Controls and ergonomics
Whilst in operational mode double functions of controls should be avoided on such controls as for pan, vertical trim, field of view and other essential functions.
The operational functions of night vision equipment should be activated directly through the operational controls; menu-driven controls should be avoided.
The operational controls of night vision equipment should meet the requirements of resolution A.694(17) as well as applicable requirements of IEC 60945.
4.16 Presentation of information
The monitor display should be non-dazzling and non-flickering. The display should be at least 200 mm in diameter.
The selected field of view, if more than one is provided, should be displayed permanently on the control panel.
