Patent ID: 8093565

Claim:
A crossed small-deflection energy analyzer (SDEA), comprising: eight plates defined by an intersection of a first pair of parallel planes spaced apart a distance D with a second pair of parallel planes spaced apart the distance D and a hemisphere having a center and a great circle, the first and second pairs of parallel planes being perpendicular to each other and to the great circle, and arranged symmetrically about the center of the hemisphere; an aperture member located adjacent and spaced apart from the great circle, the aperture member defining an entrance aperture that is centered on a line that is perpendicular to the great circle and that intersects the center of the hemisphere; an exit slit member spaced apart from a curved surface of the hemisphere, the exit slit member including an exit slit, the exit slit being defined by an intersection of a pair of perpendicular planes with a curved surface of a second hemisphere that is concentric with the hemisphere, the second hemisphere having a great circle that is coplanar with the great circle of the hemisphere and a radius that is larger than a radius of the hemisphere, one of the pair of perpendicular planes being parallel to the first pair of parallel planes, and a line of intersection of the pair of perpendicular planes being parallel to and offset from a line that contains the center of, and is normal to, the great circle of the hemisphere.