Abstract: An improved vacuum system for a system for accurately tracing on an electron sensitive film with an electron beam which passes through three (3) adjacent vacuum stages and where each stage has a predetermined vacuum level is disclosed herein. The vacuum system is a high performance, fully automatic, three (3) stage, differentially pumped system. Two (2) stages of the system each use a diffusion pump as a first pump means. The diffusion pump of the second stage is backed by a single direct drive mechanical pump and also acts as the backing pump for the diffusion pump of the first stage. The third stage uses a single direct drive mechanical pump for vacuum pumping its chamber.

Abstract: An improved particle beam recorder system having a pressure equalizing film gate including a platen for receiving a film thereon in pressure relieved relation to avoid trapping distortion causing air between the film and the platen. The platen can provide a curved film receiving surface and a predetermined tension can be applied to the recording film disposed on the platen to assure positive contact between the film and the platen. A motor driven film advance system is provided to intermittently advance the film through the film gate to thereby intermittently provide fresh and stationary film for exposure and image recording. A particle beam generator is disposed in predetermined relation with the film and the film gate and the recording beam produced thereby is electronically positionally corrected for the known geometric distortions introduced by a predetermined continuous curvature of the film gate and the predetermined tensioning of the film to produce accurate imaging on the film.

Abstract: A charged particle beam recorder having a curved film gate to impart a predetermined continuous curvature to the recording film. Predetermined tension is applied to the recording film to assure good contact of the film with the curved film gate and a motor is provided to intermittently advance the film through the film gate thereby providing fresh film for exposure. The positioning of the recording beam on the film is electronically corrected for the known geometric distortions introduced by the predetermined continuous curvature of the film gate and the predetermined tension of the film.