Abstract: A photoelectric smoke detector 1 for detecting smoke particles 4 is disclosed, the smoke detector 1 comprising: a light emitting element 5, a light receiving element 6 for receiving light 8 emitted by the light emitting element 5 and scattered by the smoke particles 4 and for outputting a detection signal 12 obtained by photoelectrical converting the received light 10, 11, an amplifier circuit 13 for amplifying the detection signal 12 and providing an amplified output signal 14, wherein the amplified output signal 14 may be divided into an offset-signal 20 and an amplified detection signal 21, whereby the photoelectric smoke detector 1 is adapted to operate in a pulsed mode, so that the detection signal 12 comprises high-frequency components, whereby the amplified detection signal 21 is determined by high-frequency components of the detection signal 12 and that the offset-signal 20 is determined by low-frequency components of the detection signal 12 and/or by low-frequency components of at least an intermedia

Abstract: A photoelectric smoke detector 1 for detecting smoke particles 4 is disclosed, the smoke detector 1 comprising: a light emitting element 5, a light receiving element 6 for receiving light 8 emitted by the light emitting element 5 and scattered by the smoke particles 4 and for outputting a detection signal 12 obtained by photoelectrical converting the received light 10, 11, an amplifier circuit 13 for amplifying the detection signal 12 and providing an amplified output signal 14, wherein the amplified output signal 14 may be divided into an offset-signal 20 and an amplified detection signal 21, whereby the photoelectric smoke detector 1 is adapted to operate in a pulsed mode, so that the detection signal 12 comprises high-frequency components, whereby the amplified detection signal 21 is determined by high-frequency components of the detection signal 12 and that the offset-signal 20 is determined by low-frequency components of the detection signal 12 and/or by low-frequency components of at least an intermedia

Abstract: Fire detector installations comprise fire detectors as sensor devices for detecting fires, smoke, flames or other signs of fire, and are used in both public buildings, such as schools or museums, and in private buildings. The invention relates to a fire detector device (1) for detecting fires and or signs of fire in an area to be monitored, said fire detector device comprising a camera element (2) for recording image data in the area to be monitored, and an evaluation element (7) designed to detect a fire or signs of fire by evaluating the image data. The fire detector device (1) is designed as a multi-criteria detector and comprises at least one other sensor element (3, 12, 13, 14) for fire detection.