Introducing the new 32mm OptoSpin
The Cairn Optospin32 continues our long tradition in filter wheel design, dating back to the 1980s, but taking full advantage of the continuing developments in motor and control technology that have taken place since then. It builds on our tried and tested approach of mounting the motor directly within the hub of the filter wheel, in order to maintain a compact size and to minimise the inertial and other losses associated with geared connections. An earlier design of this type used a relatively small wheel with 12.5mm diameter filters in order to further reduce the inertia – and hence the response time – but by using a newer and much more powerful type of motor, we have been able to obtain similar performance with this 32mm (and 25mm) filter design.
The controller box can drive up to two filter wheels simultaneously, and can interconnect with other equipment by either a digital or a USB interface. In spin mode, either or both wheels can be spun in both speed and phase synchronisation, either at an internally programmed speed, or locked to an external reference frequency. In step mode, wheels can be simultaneously but independently stepped between any combination of filter positions.