Two individually movable blades with their edges aligned parallel to each other allowing to set the slits width in the horizontal direction between 0 and 20 mm while allowing to define the slits position within the 20 mm by 20 mm window of the enclosure. Position sensors allow for closed-loop positioning of each blade to precisely define the size and the position of the aperture within the 20 by 20 mm window of the enclosure. Specialized versions are available for the use in high and ultra-high vacuum environments. Customized versions are also available. To discuss your specific requirements, please feel free to contact us at any time.