Patent attributes
A light-sensitive stain sensing system for an extractor for detecting and treating biological stains, such as food or pet stains. The stain sensing system comprises an ultraviolet light-emitting element, a visible light-emitting element, and at least one light reader. Ultraviolet and visible light beams are reflected off the surface to be cleaned into a light reader that measures reflectance values and transmits the values to a processor. The processor compares a relative reflectance value to a predetermined threshold value. The presence of a biological stain is indicated when the relative reflectance value is greater than the threshold value, and may trigger a controller to automatically adjust one or more cleaning parameters of the extractor.