A shot of the collimator's face plate. The four screws that are visible along the vertical of the face plate in this picture secure the tungsten pin cushions to the white insulating cup.
A picture of the inside of the active collimator. The tungsten pin cushions are secured onto the boron-nitride insulating cup. Another four tungsten pin cushions will be installed; see the exploded view two pictures to the right.
The grounded cup, completing the Faraday cage structure of the collimator.
A diagram that labels the components of the active collimator. Credit to Igor Senderovich.