Automatic rearview mirror for automotive vehicles
First Claim
1. In a rearview mirror for an automotive vehicle, the combination including a reflective element having a full reflectance mode and a partial reflectance mode, forward facing sensor means effective to detect light forwardly of the vehicle and generate a corresponding forward electrical signal indicative of the forward light level, backward facing sensor means effective to detect light rearwardly of the vehicle and generate a corresponding rearward electrical signal indicative of the rearward light level, forward sensor filtering means characterized by having a first time response and having a smoothing time averaging effect on the forward electrical signal and acting on the forward electrical signal to produce a filtered forward electrical signal independent of the rearward electrical signal, a rearward circuit having an input connected to said backward facing sensor means and an output, and means operable to change said reflective element between said full reflectance mode and said partial reflectance mode as a function of the output of said rearward circuit and filtered forward electrical signal, the functional time response provided by said forward sensor filtering means being slower than the functional time response provided by said rearward circuit.
1 Assignment
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Accused Products
Abstract
An improved inside rearview mirror particularly adapted for use with automotive vehicles, the mirror incorporating improved means for detecting and comparing the relative brightness of light forwardly and rearwardly of the vehicle and improved means responding automatically to annoying glare from the rear of the vehicle to move a reflective element from a full reflective mode to a partial reflective mode and also automatically return the reflective element to a full reflective mode after the source of the annoying glare is removed.
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Citations
44 Claims
- 1. In a rearview mirror for an automotive vehicle, the combination including a reflective element having a full reflectance mode and a partial reflectance mode, forward facing sensor means effective to detect light forwardly of the vehicle and generate a corresponding forward electrical signal indicative of the forward light level, backward facing sensor means effective to detect light rearwardly of the vehicle and generate a corresponding rearward electrical signal indicative of the rearward light level, forward sensor filtering means characterized by having a first time response and having a smoothing time averaging effect on the forward electrical signal and acting on the forward electrical signal to produce a filtered forward electrical signal independent of the rearward electrical signal, a rearward circuit having an input connected to said backward facing sensor means and an output, and means operable to change said reflective element between said full reflectance mode and said partial reflectance mode as a function of the output of said rearward circuit and filtered forward electrical signal, the functional time response provided by said forward sensor filtering means being slower than the functional time response provided by said rearward circuit.
- 15. In a rearview mirror for an automotive vehicle, the combination including a reflective element having a full reflectance mode and a partial reflectance mode, first photoelectric sensor means effective to detect light forwardly of the vehicle and generate a corresponding forward electrical signal indicative of the forward light level, second photoelectric sensor means effective to detect light rearwardly of the vehicle and generate a corresponding rearward electrical signal indicative of the rearward light level, forward sensor filtering means characterized by having a first time response and having a smoothing time averaging effect on the forward electrical signal and acting on the forward electrical signal to produce a filtered forward electrical signal independent of the rearward electrical signal, a rearward circuit having an input connected to said second sensor means and an output, comparator means comparing the output of said rearward circuit and the filtered forward electrical signal, rotatable DC motor means operable upon multiple revolutions thereof to move said reflective element between said full reflectance mode and said partial reflectance mode, and means controlling the energization of said motor means and controlled by said comparator means whereby said reflective element may be moved between its full reflectance mode and its partial reflectance mode as a function of the output of said rearward circuit and the filtered forward electrical signal, the functional time response provided by said, first sensor filtering means being slower than the functional time response provided by said rearward circuit.
- 31. In a rearview mirror for an automotive vehicle, the combination including a reflective element having a full reflectance mode and a partial reflectance mode, a housing defining a chamber open in the direction facing the rear of the vehicle, a base disposed at least partially within the chamber defined by said housing, means fixing said reflective element to said housing, means pivotally connecting said housing to said base whereby said reflective element and said housing may be moved as a unit between the full reflectance mode and the partial reflectance mode of said reflective element, and means including rotatable DC motor means operable upon multiple revolutions thereof to pivot said housing and reflective element as a unit between said modes relative to said base.
- 37. In a rearview mirror for an automotive vehicle, the combination including a reflective element in the form of a prism and having a full reflectance mode and a partial reflectance mode, a housing defining a chamber, a base partially disposed within the chamber defined by said housing, means fixing said reflective element to said housing whereby said reflective element faces the rear of the vehicle, means pivotally connecting said housing to said base whereby said reflective element and said housing may be moved as a unit between the full reflectance mode and the partial reflectance mode of said reflective element, first photoelectric sensor means carried by said base and effective to detect light forwardly of the vehicle and generate a corresponding forward electrical signal indicative of the forward light level, second photoelectric sensor means carried by said base and effective to detect light rearwardly of the vehicle and generate a corresponding rearward electrical signal indicative of the rearward light level, forward sensor filtering means characterized by having a first time response and having a smoothing time averaging effect on the forward electrical signal and acting on the forward electrical signal to produce a filtered forward electrical signal independent of the rearward electrical signal, a rearward circuit having an input connected to said second sensor means and an output, means effective to compare the output of said rearward circuit and the filtered forward electrical signal, and means including rotatable DC motor means mounted on said base and operable to pivot said reflective element and said housing as a unit relative to said base as a function of the comparison of the output of said rearward circuit and the filtered forward electrical signal, the functional time response provided by said first sensor filtering means being slower than the functional time response provided by said rearward circuit.
Specification