A  B  C  D  E  G  H  I  L  O  P  R  T  V

A 

Anti glare cabinet
There are many monitors on the market which do not have an anti-glare monitor cabinet. These can reflect against the windshield.

Auto brightness control
Brightness adjustment of the screen at twilight in order to avoid blinding the driver. MOBITRONIC systems are operated via the headlights.

Auto iris/Electronic Iris 
The function of the electronic iris is comparable to that of the electromagnetic iris in a camera lens. It adjusts the signal coming from a picture sensor and prevents overexposure. The higher the test-frequency for the picture signal, the more light-stable is the camera (e.g. 1/50 - 1/100.000 seconds). This is absolutely necessary for all commercial vehicles and recommended for mobile homes. The electronic iris ensures that light or shadows do not negatively effect the quality of the picture. In systems without iris control, significant problems wilI arise under the following conditions:

• light reflections from light-coloured road toppings or snow covering
• the sun in low positions
• glaring caused by headlights from behind

AUTOMATIC GAIN CONTROL (AGC) 
- An electronic circuit used by which the gain of a signal is automatically adjusted as a function of its input or other specified parameter

AUTO WHITE BALANCE
- A feature on color camera that constantly monitors the light and adjusts its color to maintain white areas.

B 

Background noise
Every electronic appliance produces a basic noise (internal interference). The effective signal, e.g., the video signal, should have the highest possible norm (usually 45 dB) so as to not be disturbed by basic noises.

B.L.C. (Back light compensation) 
Compensation for oncoming lights blending out oncoming lights by way of an additional filter level of the automatic iris control (EI).

Bracket
An electrically-insulated installation of the camera bracket to the vehicles body is recommended in order to avoid interference from random radiation.

C 

Camera cabinet 
Most of the camera cabinets are made of aluminium. To prevent corrosion, a resistant coating is necessary, (e.g., a resistant powder coating or epoxy).

  CCD picture sensor
Picture acquisition sensor on a semiconductor basis, waterproof, diameter 1/3 and 1/4 inch.

Condensation
Fogging of the lenses or the camera glasses inside the camera, which can occur as a result of significant temperature fluctuations. Compact camera cabinets or moisture-free gas fillings (e.g. nitrogen) minimizes the risk.

CMOS sensor
Complementary Metal Oxide Semiconductor, image acquisition sensor. Lower price but inferior performance when compared with CCD image sensors.

CRT (cathode radiation tube) 
Proven but space consuming screen technology. Because of the rather large monitor, a use is not always possible.

D 

Distance mark 
Stickers with guiding lines to help in determining the exact distance from the obstacle. High quality systems are equipped to phase in and shift these guiding lines electronically.

E 

E-mark  
Compatibility approval designed specially for automobiles. Is obligatory as have October 2002 and replaces the CE-inspection.

G 

Grease  
Many plugs don't give a tight connection when getting in direct contact with water. Filling the plugs with grease makes a water-resistant finish. 

H 

HORIZONTAL RESOLUTION  
- The maximum number of individual picture elements that can be distinguished in a single
scanning line. 

I  

IP (internal protection)  
Standard describing the tightness of cabinets.
IP 64 - splash-proof
IP 65 - hose-proof
IP 66 - resistant to strong water jets
IP 67 - resistant to temporary submersion
IP 68 - resistant to long-term submersion
IP 69K - resistant to high pressure cleaning
Note: Water can, however, seep into the camera as a result of capillary effect in the camera cables. These standards do not apply to the condensate information in the camera! 

L 

LCD monitors

Latest generation monitors with liquid crystal displays (LCD) offer the advantages of saving space and providing a color display The LCD monitors have a somewhat weaker lighting than the CRT monitors. The light intensity should be at least 250 cd/m2

Lens  
The image sensor used (1/3", 1/4") and the focal distance of the lens determine the displayed field of vision. The smaller the focal distance, the larger the field of vision.

LUX  
- A unit of measuring the intensity of light. (1 FC = 10 lux).

O 

Operating voltage (DC voltage/power source) 
Needed power for the monitor. The systems that can operate within the voltage range of 11-32 volts are very convenient. 

P 

Picture points (pixels)

The more picture points a CCD sensor has, the higher is the picture resolution and image contrast and hence the picture definition.

Picture tube
Picture projection through a tube. The size is usually given in inches and ranges from
4 to 7 inch screen diagonal. (1 inch = 2.54 cm)

Picture reflection (normal/mirror)
The camera picture will be mirrored upon pressing the button. That means what was previously on the left side of the screen is now on the right side. It will be necessary to make a distinction, when a second camera views the front. It is imperative, though, to make a distinction in the case of differing camera positions in order to to be able to maintain the picture on the proper side.

Plastic camera cabinet
Camera cabinets made of synthetic material are more robust that one would think. They are more resistant to salt etc., than aluminium cabinets with simple paint coats.

Protection cap
A motor-operated camera cover protects the lens from soiling. Easy set-up, which should not be used in heavy-duty areas, however.

R 

RESOLUTION
- A measure of the ability of a camera or television system to reproduce detail. That is the number of picture elements that can be reproduced with good definition. It is a factor of the pickup device or the TV CRT characteristics and the video signal bandwidth.

T 

Text on the screen (OSD)
Text information, date or distance marks are shown on the screen.

TFT technology
Image generation technology that gives especially brilliant pictures and the widest possible monitor-viewing angle. 

V 

Vibration resistance
Reversing video systems have to be able to sustain all kinds of bumps and shaking. A norm for measuring vibrations is 'g' - gravitation acceleration. The norms of standard systems are 4-5g. Heavy-duty systems have norms of up to 10g.

Video signal
Analogue signal required for image transmission. Most systems use an analogue video signal to transmit pictures. Interference-free transmission is only possible via special cables at a limited length.

Video signal format
Basically, two types of signal are used (CCIR or NTSC). This is the PAL or NTSC standard. Systems with CCIR standard (picture repetition frequency, 50 Hz) correspond to the European video standard; systems with the NTSC standard (picture recitation frequency, 60 Hz) correspond to the American standard. 60 Hz systems may show slightly flickering monitor pictures when near garage, road or yard lights.

Viewing angle
Usually two viewing angles, the horizontal and the vertical one, are of interest. The horizontal viewing angle describes the lateral view. The wider a vehicle the higher the value should be. The vertical viewing angle describes the rear view. The higher the angle the longer the rear view. A wide viewing angle let obstacles appear smaller than in reality. The user of a rear view system, therefore, should ensure familiarity with this mode of presentation.

Viewing area
The viewing area describes the observed field, which can be displayed on the monitor. The mounting height of the camera should have the proportions of 1:1:5 towards the required horizontal viewing area.