Abstract: The invention relates to a user interaction device (200, 300) comprising an optical module (210, 310) having a layer (5) of a substance being electrically switchable between a first visual state and a second visual state, and an electrical switch (6a, 6b) for electrically switching the substance between the first and second visual states, a detector (6a, 11b) for detecting the presence of a physical object, and a control unit (290, 390) for controlling the electrical switch in response to the detection of presence of the physical object.

Abstract: The invention relates to a sleep element (1) like a heating blanket for improving the sleep of a person. The sleep element comprises a property determination unit (2, 5) for determining a property of a person, a thermal energy unit (3) for transferring thermal energy to or away from the person, and a thermal energy control unit (4) for controlling the thermal energy unit depending on the determined property of the person. Since the sleep element comprises the property determination unit, the thermal energy unit, and the thermal energy control unit, the temperature of the person can be controlled depending on a determined property of the person, while the person is sleeping, such that the sleep of the person is improved. Moreover, the temperature control can simply be used within a bed by placing the sleep element in the bed. The handling of the temperature control is therefore very simple.

Abstract: The invention relates to a user interaction device (200, 300) comprising an optical module (210, 310) having a layer (5) of a substance being electrically switchable between a first visual state and a second visual state, and an electrical switch (6a, 6b) for electrically switching the substance between the first and second visual states, a detector (6a, 11b) for detecting the presence of a physical object, and a control unit (290, 390) for controlling the electrical switch in response to the detection of presence of the physical object.