This is a stepper-motor controlled variable neutral density filter system. Two opposing 25mm x 50mm filter wedges move in opposite directions on a common THK bearing slide. The density gradient is such that the area of overlap is of fairly uniform density. The range of motion allows for a density change of several orders of magnitude. In the position of greatest density, the overlap area is approximately 10mm wide.

On the side bridge plate connecting the two sides of the device a window has been milled that holds a 25mm wide and 32mm tall interference filter, 7mm in thickness. The filter is marked on its side '205'. It is a deep blue color orthogonally viewed, but pales to near-transparency as the angle increases.

The Vexta Phase 2 motor is attached to a gear-reduction drive to which the drive belt is attached. Part number of the motor is PM 266-01GK (DC 6v, 1.2A). The reduction drive is a type OM 2GK5KA. The overall dimensions of the system are approximately 10.5 inches long, 2 inches wide (not including the side bridge-plate), and 7.5 inches tall. There is an opto sensor for travel. Both the motor and sensor have cables with connectors attached. The mating connectors along with a bit of cable are attached to the connectors.

The system is in perfect condition, but we have not tested the motor drive.

Shipping Policies