[Briana, Torrey, Ian]

Decided the dichroic beamsplitter should not be flipped with the mirror because of potential back reflections in the 780 nm mirror from the 1550 nm light coming out of the crystal (schematic was reverted). Learned to do basic mode matching. We used the Nanoscan Photon beam profiler to measure the beam size (placed on the breadboard right next to the 2 by 2 breadboard) by measuring the mean 13.5% (intensity decayed to 1/e^2) beam waist (diameter) along the x and y axis at 5 different distances from a reference point (in this case, the mirror right before the lenses/crystal in the schematic). Then, Torrey's beam profiling code fit the datapoints to a Gaussian beam profile and output the location of the waist. The JamMt software was used to determine the location of the beam waist and the effect of lenses on beam size. The waist was ~13.4 inches (in beam path length) before the reference point mirror, so the waist would have been located approximately at the immediate exit of the laser. The internal laser lens was not adjusted. The beam profile and the numerical aperture from the crystal's specs (WG-1560-40) will determine whether the focal lengths of the lens are adequate. We will redo setup/alignment/beam profile measurements when the 1560 nm laser is put in place of the 1550 nm laser. Also, we found the ordered 780 nm mirrors so we will replace the 780 nm mirrors currently in use.