2022 - Optical measurement detection unit: Raman spectroscopy

relevant to the project TAČR Trend FW03010504

This instrument is the result of the design of a new optical device that enables the coupling of an excitation laser beam into the optical fiber and its subsequent delivery to the sample located inside the electron microscope chamber. The radiation produced by the interaction of the excitation light with the sample is detected by the same fiber and fed back into the designed optical device. Here, the original excitation wavelength is filtered out and the radiation produced by the interaction with the sample is analyzed using a spectrophotometer. Optical part is shown in Figure 1 and designed optical fiber vacuum feedthrough in Figure 2.

 Figure 1: Optical assembly of the device Optical measurement detection device: Raman spectroscopy. (1) Laser, (2) line filter, (3) (5) (8) adjustable mirror, (4) dichroic mirror, (6) objective lens, (7) fine four-axis manipulator, (9) longpass filter, (10) collimator, (11) spectrophotometer. The excitation branch is shown in green, the signal branch in red.

 Figure 2: Designed optical fiber vacuum feedthrough for bringing an optical fiber into the electron microscope chamber. On the left: a photo of the installed feedthrough, on the right: a detail of the fiber sealing mechanism.