Abstract: A lithographic projection apparatus having a masking device for obscuring part of at least one of a patterning device used for patterning a projection beam before imaging the patterned beam onto a substrate. The masking device includes a first masking structure to obscure said part of said patterning device in a first direction and a second masking structure to obscure said part in a second different direction, wherein said first and second masking structure are disposed in the vicinity of said focal plane in a mechanically uncoupled arrangement with respect to each other.

Abstract: A lithographic apparatus includes a guiding mechanism to guide a movable structure such as a mask blade of a reticle masking device, a movable part connected to the movable structure, and a substantially stationary part to guide the movable part. The movable part includes a nozzle to inject a gas in a gap between the movable and stationary parts, a contactless supply of the gas from the stationary part to the movable part being provided by a gas supply outlet in the stationary part and a gas supply inlet in the movable part. The gas supply outlet includes an inlet trench in a surface of the movable part facing the gas supply outlet of the stationary part, the trench being orientated parallel to a direction of movement of the movable part. The movable part includes a motor drive part and a counter weight part connected to an end of the motor drive part facing away from the movable structure.