Vicky, Camilla, Dhruva. WP 10257. Following 2019 EY swap alogs 52500, 52513, 52551.

We removed the old multi-mode fiber, fiber launcher D1800125 and lens labeled F=125.0 N-BK7. We left old diode source M530F2 on table but will remove. 

Used a ADAFC4 fiber coupler to connect the new S&K 51NANO 520nm laser with a TN532R5A1 50/50 fiber splitter. We plugged the power supply into the mains (no interlock but is eye-safe). Measured power out of splitter to be 1.6mW (expect max of 3.6mW). This converts the 3B laser to a 3R which is now eye-safe (still VEA laser hazard as the enclosures is open and ALS beam present). We added a sign to the inside and outside of the table saying that the fiber splitter should not be removed. See TSOPM1900163. The final version of the laser should be off-table and in a box that converts it to 3R with a single mode fiber output coupler.

We added a f=40mm lens around 45mm from the fiber launcher. This focused the beam ~4” after HWS-L3 (D1800270). 

We aligned the beam through the system and got two return beams to the CCD camera. One beam moves with ETMX alignment adjustment, the other moves with TMSX. See photo. Our imagining plane must be incorrect, the beam also looks too small. We'll continue tomorrow.