Classification Of Particles By Means Of Spectral Analysis

A particle detection unit (200) with a light transmitter (210) for emitting light along a light path (110, 111) and a light receiver (220) for detecting at least a portion of the emitted light within an incidence region (120, 121), as well as a control module (230) connected to the light transmitter (210) and the light receiver (220) for signal transmission, wherein the light transmitter (210) and the light receiver (220) are oriented with one another to define a detection region (DB), and the control module (230) is configured to detect particles located in the detection region (DB) based on the light detected by the light receiver (220), characterized in that

• the light transmitter (210) has at least a first light source (241) configured to emit light of a first characteristic wavelength (λ1), and a second light source (242) configured to emit light of a second characteristic wavelength (λ2), as well as a reference light source (240) configured to emit light of a characteristic reference wavelength (λ0), and/or
• the light receiver (220) comprises at least a first light sensor (251) configured to detect light of a first characteristic wavelength (λ1), and a second light sensor (252) configured to detect light of a second characteristic wavelength (λ2), as well as a reference light sensor (250) configured to detect light of a characteristic reference wavelength (λ0), wherein
• the first and second light sources (241, 242) and the reference light source (240) of the light transmitter (210) are oriented with one another in such a way that the light emitted in each case at least partially superimposes one another, defining a common light path (110) along the optical axis (211) of the light transmitter (210), and/or
• the first and second light sensors (251, 252) and the reference light sensor (250) of the light receiver (220) are oriented with each other in such a way that the light detectable by the respective light sensor (250, 251, 252) at least partially superimposes each other, defining a common region of incidence (120) along the optical axis (221) of the light receiver (220), and wherein
• to define the detection region (DB) the region of incidence (121) or common region of incidence (120) of the light receiver (220) is oriented with the common light path (110) of the light transmitter (210) or the light path (111) or common light path (110) of the light transmitter (210) is oriented with the common region of incidence (120) of the light receiver (220).