At Diamond Light Source we have built and developed a state-of-the art optical metrology laboratory which is equipped with instruments to test and inspect extremely precise mirrors used to focus X-rays for Diamond’s beamlines.
To calibrate this measuring equipment we needed a device that can produce very tiny angle changes in a precise and controlled way.
Imagine a 1m long spirit level set on a flat surface, then place a 1mm spacer under one end. That gives an angular change of 1/1,000 of a radian or 1 milliradian. Radians are an alternative way of describing angles instead of degrees.
Now, instead of a 1m spirit level, we use a 1000km long spirit level, with a 1mm spacer under one end. This would create an angular change of 1 nanoradian, which is exactly what Diamond’s Nano-angle generator (NANGO) can accuractely create.
Image: Diamond-NANGO, with its rotation axis pointing in the horizontal direction.