Method and apparatus for removing and preventing lens surface contamination on a vehicle lens
A vehicle includes a vehicle frame and an optical device mounted on the vehicle frame. A first temperature sensor senses ambient air temperature surrounding the vehicle frame, a second temperature sensor senses a temperature of a lens of the optical device, and a humidity sensor senses moisture content of air proximal to the lens. An exhaust directs gas at the lens in response to the sensed ambient air temperature, the sensed lens temperature, and the sensed moisture content.
1. A vehicle comprising:
a vehicle frame;
an optical device mounted on said frame and including a lens having an exterior surface exposed to ambient air surrounding said vehicle;
a first temperature sensor sensing air temperature of said ambient air surrounding the vehicle;
a second temperature sensor sensing a temperature of said lens;
a humidity sensor sensing moisture content of air proximal said lens; and
an exhaust directing a gas at said lens exterior surface in response to said ambient air temperature sensed by said first temperature sensor, said temperature of said lens sensed by said second temperature sensor, and said moisture content sensed by said humidity sensor.
2. The vehicle as in claim 1 , including a heater heating said gas directed by said exhaust.
3. The vehicle as in claim 2 , in which said heater heats said gas directed by said exhaust and lowers moisture content in said gas directed by said air exhaust below the moisture content sensed by said humidity sensor.
4. The vehicle as in claim 1 , including a blower urging said gas directed by said exhaust out of said exhaust.
5. The vehicle as in claim 4 , in which said blower is operable at different speeds, wherein each speed causes a different amount of flow of said gas directed by said exhaust to exit said exhaust at said lens.
6. The vehicle as in claim 1 , in which said exhaust directs a steady stream of gas at said lens.
7. The vehicle as in claim 1 , in which said exhaust directs pulses of gas at said lens.
8. The vehicle as in claim 1 including a processor calculating a dew point of air proximal said lens based upon said ambient air temperature sensed by said first temperature sensor, said temperature of said lens sensed by said second temperature sensor, and said moisture content sensed by said humidity sensor, wherein said exhaust directs gas at said lens when said dew point is greater than or equal to said temperature of said lens sensed by said second temperature sensor.
9. The vehicle as in claim 1 , in which said temperature of said lens sensed by said second temperature sensor is a temperature of an exterior surface of said lens.
10. The vehicle as in claim 9 , in which said exhaust directs gas at said exterior surface of said lens.
11. A method of removing and preventing lens surface moisture contamination from a lens of an optical device mounted on a frame of a vehicle, said method comprising;
sensing an ambient air temperature of ambient air surrounding a vehicle;
sensing a lens temperature of a lens of an optical device mounted on the vehicle and exposed to said ambient air surrounding said vehicle;
sensing moisture content of air proximal said lens; and
directing moisture contamination removal gas at an exterior surface of said lens in response to said ambient air temperature, said lens temperature of said lens, and said moisture content of air proximal said lens.
12. The method as in claim 11 , including heating said moisture contamination removal gas prior to directing the moisture contamination removal gas at said lens.
13. The method as in claim 11 , including lowering moisture content in said moisture contamination removal gas below the moisture content of air proximal said lens.
14. The method as in claim 11 , including urging said moisture contamination removal gas at said lens using a blower.
15. The method as in claim 14 , including operating said blower at different speeds, wherein each speed causes a different amount of flow of said moisture contamination removal gas at said lens.
16. The method as in claim 11 , including directing a steady stream of moisture contamination removal air at said lens.
17. The method as in claim 11 , including directing pulses of moisture contamination removal air at said lens.
18. The method as in claim 11 , including calculating a dew point of air proximal said lens based upon said ambient air temperature, said lens temperature of said lens, and said moisture content of air proximal the lens, and then directing said moisture contamination removal air through said air exhaust at said lens when said dew point is greater than or equal to said lens temperature of said lens.
19. The method as in claim 11 , in which said lens temperature of said lens is a temperature of an exterior surface of said lens.
20. The method as in claim 19 , in which said air exhaust directs moisture contamination removal gas at said exterior surface of said lens.