Matt, TJ, Camilla

Today we did proof of principle measurements of the CHETA beam size using the FLIR camera.

In 13940 the CO2 beam was projected onto black construction paper in the LVEA. Today we projected the CHETA beam (at low power, <100mW) onto the laser curtains in the CHETA lab. We measured it using a ruler with paper markings taped on at 2" increments, it was easier to see the ruler once it was warmed up by our hands.

We also moved the QPD 2" lens 200mm FL into the path 230mm after M4 and 500mm from M4, for both of these, the beam appeared to be ~1" in diameter. The laser curtain was 67" from M4. Photo attached.