The new infrared beamline at NSRL.

• A new Infrared beamline was constructed at HLS II. • Details of the optics and experimental techniques at the beamline. • High performance of the infrared beamline and endstations. National Synchrotron Radiation Laboratory (NSRL) owns the first dedicated synchrotron radiation facility in China, Hefei Light Source (HLS). The HLS was fully upgraded to HLS II in 2016. Following the machine upgrade, the infrared beamline was reconstructed to match the new storage ring and improved its performance. The infrared radiation is extracted from a bending magnet (1 degree port) with an acceptance angle of 65(H) × 55(V) mrad2, which including edge radiation and constant field radiaton. Two endstations were reconstructed. One is for spectroscopy experiment covering from far to near infrared, the other one is for mid-infrared microspectroscopy and imaging experiment. In this paper, we introduce the new infrared beamline and endstations in detail, including optics, experimental techniques developed at two endstations. [ABSTRACT FROM AUTHOR]