Patent ID: 8531670

Claim:
An optical turbidity sensor for detecting a property of wash water, wherein the optical turbidity sensor is configured for installation in a household washing machine or dishwasher producing the wash water, the optical turbidity sensor comprising: a housing having a housing interior and shaped to have an exterior housing section defining a wash water receiving space in direct contact with a portion of the produced wash water; and a measurement module arranged in the housing interior, having a light-emitting element and a light-receiving element, the measurement module defining a measurement light path which extends from the light-emitting element to the light-receiving element and passes outside the housing over a part of its path length wherein the light-emitting element and the light-receiving element are arranged together in a first subspace of the housing interior, and the measurement light path extends over a part of its path length through at least one second subspace of the housing interior, which is sealed from the first subspace.