Apparatus for automatically controlling transmission of light through a lens system
AssigneePolaroid Corporation
InventorChristian C. Petersen
Life of this patent
Estimating the term…
Abstract
An electromagnetic actuator has a motor that indexes an armature element repeatedly by one step from a rest position, and has an electromagnetic clutch coupled with the armature element to increment an optical element that controls light according to relative position. In adjustable polarizing sunglasses, the actuator incrementally rotates a polarized element in each lens in response to the brightness which a sensor receives through the sunglasses. An electrical control circuit compares, in each operating cycle, the sensor signal with high and low reference values to select the motor drive signal.
Claims14
In an automatic apparatus for continuously providing light responsive mechanical adjustment of the intensity of the light transmitted through a lens system by displacing at least one optical element of the lens system relative to a supporting member, the improvement comprising:
- electrical control means for continuously sensing the intensity of light transmitted by the lens system and for continuously providing an electrical control signal responsive to a deviation in the intensity of the sensed light from a preselected level of light intensity;
- and
- electromagnetic actuator means for displacing the one optical element of the lens system relative to the supporting member in response to said electrical signal to maintain the intensity of light transmitted by the lens system substantially at said preselected level of light intensity regardless of changes in the intensity of light incident to the lens system.
An automatic variable light transmissive eyeglass device for continuously providing light-responsive mechanical adjustment of the intensity of the light transmitted by the device to the eye of the user, said device comprising:
- an eyeglass frame;
- lens means mounted with respect to said frame for controlling the light transmitted by the eyeglass device, said lens means including at least one light transmissive optical element mounted for displacement with respect to said frame for controlling the intensity of light transmitted through said lens means;
- electrical control means for continuously sensing the intensity of light transmitted by the eyeglass device, and for continuously providing an electrical control signal responsive to a deviation in the intensity of the sensed light from a preselected level of light intensity;
- and
- electromagnetic actuator means for displacing said optical element relative to said frame in response to said electrical control signal to maintain the intensity of light transmitted by the eyeglass device substantially at said preselected level of light intensity regardless of changes in the intensity of light incident to the eyeglass device.
Dependencies are inferred from the claim text.