Abstract: An inter-digital capacitive sensor and control system are used to distinguish between rain, ice, dirt and debris on the outer lens surface of a surveillance camera. The electrodes of the capacitive sensor are made from a conductive coating such as printed epoxy or a transparent conductive oxide, that is directly deposited onto the inner surface of the lens. A defroster is spaced radially-outward from the capacitive sensor and is formed by metal deposition directly on the substrate surface.

Abstract: A cleaning method for a surveillance camera uses a capacitive sensor to determine whether rain, ice, dirt, debris or other foreign objects are present on the camera lens substrate. A determination is made whether the sensed capacitance is greater than a first threshold indicative of the presence of a foreign object on the lens. If a foreign object is indicated, the lens is sprayed with a sprayer and then a wiper is activated. If a foreign object is not indicated, a determination is made whether ice is present by comparing the sensed capacitance to a second threshold that is less than the first threshold. If ice is present, wiper and lens defrosters are activated, and a wiper is then turned on. The cleaning method may include a temperature sensor and power management for the defrosters.

Abstract: An inter-digital capacitive sensor and control system are used to distinguish between rain, ice, dirt and debris on the outer lens surface of a surveillance camera. The electrodes of the capacitive sensor are made from a conductive coating such as printed epoxy or a transparent conductive oxide, that is directly deposited onto the inner surface of the lens. A defroster is spaced radially-outward from the capacitive sensor and is formed by metal deposition directly on the substrate surface.

Abstract: A cleaning method for a surveillance camera uses a capacitive sensor to determine whether rain, ice, dirt, debris or other foreign objects are present on the camera lens substrate. A determination is made whether the sensed capacitance is greater than a first threshold indicative of the presence of a foreign object on the lens. If a foreign object is indicated, the lens is sprayed with a sprayer and then a wiper is activated. If a foreign object is not indicated, a determination is made whether ice is present by comparing the sensed capacitance to a second threshold that is less than the first threshold. If ice is present, wiper and lens defrosters are activated, and a wiper is then turned on. The cleaning method may include a temperature sensor and power management for the defrosters.