[Tanaka,Hirose,Saito]

Based on the optical layout plan in klog:36739, we installed mirrors, lenses, and a beam splitter.
To achieve mode matching, we measured the beam profile after the first lens.
In addition, two irises were installed to align the optical path of the sub-laser beam with IR laser on the POS table.
 

• Following klog:36746, we installed mirrors and lenses (Photo 1). We completed the installation of optical components required for mode matching and alignment of the sub-laser.
   
• To fine-tune the position of the first lens and match the waist after the first lens to the calculated result (klog:36739), we first placed a beam profiler at the calculated waist position and adjusted the setup so that the waist size matched the calculated value. Then, we measured the beam profile after the first lens. The fitting will be performed later.
   
• To align the optical path of the sub-laser beam with IR laser on the POS table, we installed two irises. The first iris was placed immediately after the first lens that the IR beam passes through after passing through the periscope on the POS table. The second iris was placed in front of the mirror used during the beam profile measurement. We plan to perform alignment so that the sub-laser beam passes through the irises, using the mirrors and beam splitter installed after the lenses for mode matching.