Opto Sigma's GOTHA-B 2-Axis Goniometers are large platform all-aluminum stages with exceptionally high rotation-axis height, of 182mm (about 7 inches high). They are driven by a high-tolerance worm-gear mechanism which, along with its high precision ball-bearing guides, yields angular position readable to 1 arc minute using the vernier scale. As with 1-axis goniometers, the axis of rotation is situated parallel to and above the mounting platform. Opto Sigma's 2-axis goniometers have intersecting orthogonal axes of rotation. In this configuration, they have capability for orbit-like positioning about a single point. In this configuration, they have capability for orbit-like positioning about a single point. The GOTHA series of goniometers are lockable and finished in a RoHS-compliant black anodize.