BMW 01 41 0 155 307 - Manual (Page 176)

176 n Interior rearview mirror with automatic dimmer *
The interior rearview mirror with auto-
matic dimming feature reduces blinding
from following traffic by adapting the
intensity of the reflected images to
correspond to levels of light registered
by the unit's sensors. The mirror reverts
to its undimmed setting as soon as the
light source disappears. One light
sensor is mounted on the front of the
mirror housing. This sensor, the one
that is directed forward, measures light
intensity in the area ahead of the
vehicle. The second sensor is inte-
grated within the mirror's glass. The
electronic control system compares the
light intensity from front and rear. The
difference provides the basic parameter
used to modulate an electrical current
and induce chemical changes in a
semisolid layer incorporated in the lens.
463us013
The semisolid reacts chemically to
this electrical current, thus providing
dimming of the mirror through an infi-
nitely-variable range (electrochromic
technology).
As a result, it is no longer necessary to
dim the mirror manually, and the driver
can concentrate completely on traffic
conditions.
Online Edition for Part No. 01 41 0 155 307 - © 09/00 BMW AG