The TLS 14A IR beamline was designed to extract mid-infrared radiation for FTIR microspectroscopy studies, collecting 70 x 30 mrad2 (H x V) of the radiation generated by a bending magnet of Taiwan Light Source (TLS) storage ring of 1.5 GeV, covering spectral range of 4000-400 cm-1 (2.5 - 25.0 micron in wavelength). The highly collimated beam provides high lateral resolution and which is especially suitable for measurements on micron-sized samples.
The optics of the beamline consists of a plane mirror (M1), two polynomial mirrors (M2 and M3), and several steering and collimating mirrors (M4 is off-axis paraboloid and M5 is plane mirror), designed by using SHADOW ray tracing simulation . Mirror M1 is water-cooled and made of explosion-bonded Glidcop/ stainless-steel substrate, located 1.22 meters from the arc source of bending magnet. Mirror M1 is with a centered slot for transmitting the X-rays radiation trapped by a water-cooled beam dump, installed with its manipulator inside of chamber of the bending magnet. Mirrors M2 and M3 are high-order polynomial bendable to effectively and precisely focus the infrared radiation from extended arc source of the bending magnet [2-5] at the same location at the downstream beam path for the focused spot by applying stresses against the short-side of mirrors M2 and M3, respectively, to alter the focus length for each of M2 and M3 as illuminated in the Figure 1.
The end-station includes FTIR Spectrometer and Infrared microscope. The beamline is currently set up for multidisciplinary studies.
Figure 1. The optical layout of the NSRRC TLS 14A IR beamline.