US 4,398,823 A · Extended range monochromator

Abstract

An extended range grazing incidence monochromator is disclosed which utilizes Rowland circle geometry to select a frequency of radiation from a broad spectrum of radiation, with the entrance slit and the gratings of the monochromator being positionable by remote electrical control, such as that provided by a digital computer, while the exit slit of the apparatus remains fixed. The monochromator has an extended range because it includes two different gratings, each of which has an optical characteristic adapted for use in a Rowland circle of a different size, and the apparatus is capable of switching between two gratings without breaking the ultra-high vacuum contained in the interior of the monochromator. The positioning of the entrance slit and the appropriate grating is accomplished both rotationally and linearly through the use of stepping motors which can be precisely remotely controlled for maximum accuracy and control.

Claims13

Dependent claims

An extended range monochromator adapted for operation in an ultra-high vacuum comprising

an entrance slit which is rotatable about an axis of rotation;
first and second grating arms rotatable about the axis of rotation of the entrance slit;
first and second gratings mounted on the respective first and second grating arms, the respective gratings provided with optical characteristics adapted for use in Rowland circle geometries of two different sizes;
a fixed exit slit;
linear positioning means connected so as to translate and position the entrance slit and the first and second grating arms as a unit linearly with respect to the fixed exit slit;
rotational positioning means connected so as to separately rotationally drive and position each of the entrance slit, the first grating arm, and the second grating arm;
the linear positioning means and the rotational positioning means adapated to being remotely electrically controlled and being operable without breaking the vacuum of the monochromator so that the entrance slit and a selectable one of the two gratings can be linearly and rotationally positioned to project a selectable frequency of radiation through the exit slit.

4 more elements

In a monochromator utilizing Rowland circle optics including an entrance slit, a grating, and an exit slit, and adapted for operation in a vacuum, the improvement comprising

a movable optical carriage carrying the entrance slit and the grating with the exit slit remaining fixed;
linear positioning means remotely electrically controllable to linearly position the optical carriage;
a rotatable entrance slit mounting carrying the entrance slit;
a grating arm carrying the grating thereon, the grating arm being rotatably mounted on the rotatable entrance slit mounting so that the entrance slit and the grating arm are rotatable about the same axis;
and
independent rotational positioning means for each of the entrance slit mounting and the grating arm, the rotational positioning means being remotely electrically controllable so that a selectable frequency of radiation can be directed through the exit slit by appropriate linear and rotational positioning of the entrance slit mounting and the grating arm.

3 more elements

Dependencies are inferred from the claim text.

Extended range monochromator

Life of this patent

Extended range monochromator

Life of this patent

Abstract

Claims13