Miklos, A.A.MiklosAngster, J.J.Angster2022-03-082022-03-082007https://publica.fraunhofer.de/handle/publica/308104(B3) Die Erfindung betrifft eine photoakustische Multipass-Zelle, mit einer Lichtquelle und konzentrierend ausgebildeten Mitteln (3) zur Reflexion des Lichts in einem akustischen Resonator (8), die konzentrierend ausgebildet sind.WO 2008116658 A1 UPAB: 20081024 NOVELTY - The multipass cell has a light source and two concentrating reflecting units i.e. spherical mirrors (3), for reflecting light in an acoustic resonator (8). The light source is arranged between the concentrating units which have a common optical axis. The light source is constituted by a laser diode or a fiber (5) that is guided into the photo-acoustic multipass cell. The two reflecting units have same radii, and the light source is operated at a center point of the reflecting units. USE - Photo-acoustic multipass cell for use in a photo-acoustic measuring system (claimed). ADVANTAGE - The light source is arranged between the concentrating units, thus providing multipass cell that is very sensitive and eliminates the need for accurate adjustment of the light ray.de690patent102007014518