The invention relates to a device for measuring at least one gaseous or solid material in at least one measurement volume at a stationary measurement station, wherein: a light source and at least one detector are provided, and at least one main primary beam can be emitted from the light source to at least one beam splitter unit; the at least one beam splitter unit is disposed at a first distance from a first reflection region of a reflection unit, and the beam splitter unit splits the main primary beam into at least one first partial beam oriented through the measurement volume toward the first reflection region and at least one secondary primary beam oriented in a different direction than the main primary beam; at least one deflecting unit is disposed at a second distance from a second reflection region, and the at least one secondary primary beam can be directed to the deflecting unit by means of the beam splitter unit and the at least one secondary primary beam can be directed, as a second partial beam, through the at least one measurement volume toward the second reflection region by means of the deflecting unit; and each of the at least one measurement volume is disposed between the beam splitter unit and/or the deflecting unit and the associated reflection regions and is at least partly delimited by the beam splitter unit and/or the deflecting unit and the associated reflection regions. According to the invention, the first reflection region directs the first partial beam, as a first return beam, through the at least one measurement volume to the at least one detector, the second reflection region directs the second partial beam, as a second return beam, through the at least one measurement volume to the at least one detector, and the at least one detector measures a light property of each return beam, said light property characterizing the at least one gaseous or solid material.