The CaliBall™ is used to calibrate interferometer transmission spheres by using the Random Ball Test (RBT). The Random Ball Test was used with some success in the past but the materials that the balls were made from limited the measurement accuracy. The CaliBall™ has overcome the accuracy dilemma since it is made from silicon nitride. The 25mm balls are grade 5 (round to better than 125nm), have a surface finish of ~1.3nm rms, are opaque and 11% reflective. Virtually indestructible, Caliball™ is a practical solution that can be used repeatedly in a calibration environment for years without degradation.

Details of the CaliBall™ I package:

A Grade 5, 1” diameter Silicon Nitride ball with a reflectivity of about 11% for use in the Random Ball Test for calibration Transmission Spheres
A 3 ball kinematic mount with Silicon Nitride balls for precise, repeatable positioning the CaliBall during the calibration
A sturdy, polypropylene carrying and storage case for the CaliBall and mount suitable for use and storage in a clean room
A Certificate of Compliance of a random sample of the balls produced in the lot from which the ball was taken showing the typical ball roundness and finish
Complete instructions for how to perform the Random Ball Test to any level of precision in a given environment
The CaliBall™ I is particularly well suited for calibrating downward looking interferometers and can also be used with horizontal looking interferometers with transmission spheres as fast as f/0.7. A customer supplied x-y-z stage is required to position the CaliBall™ I at the focus of the transmission sphere to be calibrated.

Disclaimer: All specifications and prices are subject to change.