US 11,903,102 B1
Defogging system using a transparent condensation sensor and heater
Noah Lassar, Santa Cruz, CA (US); and Yiwei Wang, Sunnyvale, CA (US)
Assigned to Waymo LLC, Moutain View, CA (US)
Filed by Waymo LLC, Mountain View, CA (US)
Filed on Nov. 30, 2020, as Appl. No. 17/106,385.
Int. Cl. H05B 3/84 (2006.01); H05B 1/02 (2006.01); H05B 3/34 (2006.01); B60S 1/56 (2006.01); B60H 1/00 (2006.01); B60S 1/02 (2006.01)
CPC H05B 3/84 (2013.01) [B60H 1/00785 (2013.01); B60S 1/026 (2013.01); B60S 1/56 (2013.01); H05B 1/0236 (2013.01); H05B 3/34 (2013.01); H05B 2203/013 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A sensor assembly, comprising:
a cover element disposed in a window of the sensor assembly, the cover element being configured to pass signals of one or more wavelengths therethrough, the cover element having a first side and a second side opposite the first side;
a sensor device configured to perform at least one of emit or receive signals of the one or more wavelengths through the cover element, the sensor device being disposed along the first side of the cover element;
a moisture sensing and heating layer disposed on the first or second side of the cover element, the moisture sensing and heating layer having a pair of electrically conductive complementary elements spaced apart a selected distance from one another, the pair of electrically conductive complementary elements covering an area of the first or second side of the cover element in a pattern and being transparent to the one or more wavelengths; and
a control module operatively coupled to the pair of electrically conductive complementary elements, the control module being configured to:
detect presence of moisture along the cover element of the sensor assembly based on signals received from the pair of electrically conductive complementary elements,
upon a determination from the signals that the moisture exceeds a threshold value, cause the pair of electrically conductive complementary elements to heat up to dissipate the moisture, and
upon a determination from the signals that the moisture falls below the threshold value, cause the pair of electrically conductive complementary elements to cease heating.