Abstract: Provided is a device which includes a method for the coherent detection of an optical signal, including the following steps of providing a vertically illuminable photodiode; producing an optical reference signal; radiating the optical signal and the reference signal into the photodiode in such a way that the two signals at least partially interfere with each other. Radiating the optical signal into the photodiode is effected via a first side of the photodiode, and radiating the reference signal into the photodiode is effected via a second side of the photodiode, or, vice versa, the reference signal is radiated into the photodiode via the first side of the photodiode and the optical signal is radiated into the photodiode via the second side.

Abstract: A method for distance measurement by means of an active optical sensor system is disclosed, comprising: an initial pulse sequence with an initial frequency spectrum, which corresponds to a frequency comb, is generated using a laser source. Based thereon, a first pulse sequence and a first reference pulse sequence with a first frequency spectrum, which corresponds to a first part of the frequency comb, as well as a second pulse sequence and a second reference pulse sequence with a second frequency spectrum, which corresponds to a second part of the frequency comb, are generated. A first distance of the object is determined using a first heterodyne measurement based on the first reference pulse sequence and reflected portions of the first pulse sequence and a second distance is determined using a second heterodyne measurement based on the second reference pulse sequence and reflected portions of the second pulse sequence.