BMW 7 Series: Principles Of Operation

The BMW Night Vision camera is a thermal imaging camera, which converts thermal radiation into electronic signals and then into images visible to the human eye.

The thermal image is converted first by the sensor into electrical signals and then with the aid of imageprocessing software into a visible image in the control display.

The sensor elements alter the resistance in proportion to the temperature. The higher the temperature, the higher the electrical signal and the whiter the pixel will be shown.

Thanks to increased dynamic sensitivity, the sensor can generate a new image up to 60 times per second. This results in a softer and clearer image.

Heat radiation is absorbed and dissipated by virtually every solid or liquid body. Heat radiation, however, is not visible to the human eye because it belongs in the long-wave infrared range. From a physical standpoint, this represents electromagnetic waves with a wavelength of 8 μm to 15 μm. This long-wave infrared radiation is known as Far Infrared (FIR).

The advantage of utilizing radiation in the Far Infrared range is the greater range compared with Near Infrared systems with a wavelength of 0.7 μm to 1.4 μm. These systems require illumination with just this wavelength.

Essentially, FIR systems consist of an optical element, a thermal imaging camera, an control unit and a display.

Diagram Representing Principle of Operation

Fig. 13: Operation Diagram Of Night Vision Camera

Switch-On Conditions

BMW Night Vision is activated as soon as the button in the light switch center is pressed.

The following basic conditions can exist:

• The rain/light sensor detects sufficient ambient light and the driving lights are switched off; BMW Night Vision is ready for operation approx. 2 seconds after the button in the light switch center is pressed. A message is shown in the control display during this period of 2 seconds.

Fig. 14: Identifying Switch/Button On E65/E66

• The rain/light sensor detects insufficient ambient light and the driving lights are switched on; BMW Night Vision is ready for operation immediately after the button is pressed.
• In conditions of darkness (underground car park), the driving lights are switched off and the driving speed is less than 5 km/h; BMW Night Vision is ready for operation after the button in the light switch center is pressed.

Fig. 15: Identifying Switch/Button On E60/E61/E63/E63

BMW Night Vision cannot be activated when:

• the driving lights are switched off,
• the rain/light sensor detects insufficient ambient light, and
• the driving speed is greater than 5 km/h

Once BMW Night Vision has been activated, a message appears in the control display to the effect that the system cannot be used at night without driving lights.

Operation by iDrive

Calling up Settings

The individual functions and settings can be selected and activated via the iDrive.

The following settings can be called up:

• Night Vision off (not E65)
• Zoom
• Curve mode
• Full screen
• Contrast
• Brightness

A tick/check symbol indicates when zoom, bend/curve mode or full screen is activated.

Fig. 16: Display Of E65/E66 Settings Menu

Fig. 17: Display Of E60/E61/E63/E64 Settings Menu

Calling Up Menu

The BMW Night Vision menu can only be called up when the system is activated.

When the preconditions are in place, the menu can be called up for example from the Start menu as follows:

• Briefly press the controller. The "BMW Night Vision" menu appears in the control display
• Select the desired menu item, e.g. "Brightness", by turning the controller
• Press the controller to activate the function
• Set the desired value and confirm by pressing
• Select the menu item "Back" and quit the "BMW Night Vision" menu

Zoom - Angle of View of Camera

When the "Zoom" function is activated, BMW Night Vision automatically switches to a 1.5 times enlargement of the display at speeds in excess of 44 mph (70 km/h). The camera's angle of view is reduced to 24º here.

Zoom is deactivated automatically again when the speed drops below 37 mph (60 km/h). The camera's angle of view reverts to 36º. Zoom is calculated by the camera.

Angle of View of Camera

Fig. 18: Identifying Zoom - Angle Of View Of Camera

NOTE: The "Zoom" function can only be selected when the "Full screen" function is deactivated.

Bend/Curve Mode

Depending on the driving situation, the image detail follows the cornering path of the vehicle along the same lines as the directional headlights.

The image detail is calculated in the camera.

Bend/curve mode is only available when the "Zoom" function is activated.

For better understanding, the following graphic shows a driving situation in which the "Bend/curve mode" function is activated.

Fig. 19: Identifying Bend/Curve Mode Function

Full Screen

In the case of the "Full screen" function, the Assist window is removed and the thermal image is shown over the entire width of the control display. 640 x 240 pixels (for full screen) and 400 x 240 pixels (for split screen) are used to display the BMW Night Vision image.

Fig. 20: Identifying Full Screen In Control Display

Contrast and Brightness

Both values can be personalized and changed on a scale between -10 and 10.

Fig. 21: Display Of Contrast And Brightness

Visibility

Normal driving-light illumination is approximately 328 ft (150 m).

The use of BMW Night Vision enables heat emitting objects to be detected up to a distance of approx. 984 ft (300 m).

This specified distance is dependent on weather factors.

For example, heavy fog or rain reduces visibility.

Fig. 22: Comparison Of BMW Night Vision Visibility With Different Vehicles Headlights

The driving speed must be adapted to the relevant visibility conditions in each case. BMW Night Vision is designed as a supporting system, which, with a modified driving style, affords the driver an early, better overview of the road conditions ahead of the vehicle.

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