Abstract: A microfiche reader assembly especially suitable for use in a desk drawer of typical size is disclosed herein. This assembly includes a housing, a projection screen, a microfiche support arrangement for supporting a microfiche for movement within a given rectangular operating area and an optical arrangement cooperating with the supported microfiche for projecting an enlarged image of a section of the microfiche on to the screen when the microfiche is in its operating area. While this assembly requires more room than the standard desk drawer allots during use, it is made sufficiently collapsible to fit entirely within the confines of the drawer when not in use so as to allow the drawer to be closed. However, at the same time, the assembly is expandable for use within the drawer when the latter is opened, whereby the assembly does not have to be removed.

Abstract: A microfiche reader is disclosed herein and includes an assembly for supporting a microfiche in a given area, a projection screen and an optical arrangement for providing an image of a segment of the microfiche on the screen. This arrangement utilizes a dual projection lens assembly and a dual condenser lens assembly which cooperate with one another so that the magnification of the projected image can be easily varied between two levels. As disclosed, the dual projection lens assembly itself includes two distinct projection lenses which are contained in collapsible housings. Moreover, each of these latter lenses is adjustably focused by rotational movement of its associated housing and remains in the focusing position selected unless its housing is again rotated.

Abstract: A linear beam scanning apparatus especially suitable for recording data on light sensitive film is disclosed herein. This apparatus starts with a modulated beam of collimated light and utilizing a suitable device, preferably a holographic grating scanner, converts this stationary beam to a first continuously scanning beam of light having a particular cross-sectional segment thereof which repeatedly moves, that is scans, from a first point to a second point along an arcuate path. This arcuately scanning beam is then converted by optical means to a second continuously scanning beam which converges to a point and which repeatedly moves, that is scans, from one end of a straight line path to its other end.

Abstract: A microfiche reader is disclosed herein and includes an optical arrangement for providing an image of a supported microfiche on a projection screen. This optical arrangement utilizes a beam of light which is directed from a light source along a path through the microfiche and towards the back side of the screen. A condenser lens is located on this beam path between the microfiche and light source and includes a focal point also located on the path but on the other side of the microfiche. A projection lens assembly is located between the microfiche and the focal point of the condenser lens, again on the beam path, such that there is a predetermined spacing between the projection lens assembly and focal point. This spacing is selected to increase and preferrably maximize illumination efficiency of the overall optical arrangement.

Abstract: A microfiche reader assembly for optically projecting a microfiche image on the backside of a screen for viewing from its front side is disclosed herein. This assembly includes a housing having an inner chamber, a projection screen supported by the housing and a support for the microfiche itself. A beam of light is passed through the microfiche along an incoming path and into the chamber where a plurality of light reflecting surfaces are utilized to redirect the same beam onto the backside of the screen along a plurality of different paths including a final path incident with the screen and at least one intermediate path between the incoming and incident paths. These paths are specifically selected to improve image contrast and corner image brightness at the screen and to provide a relatively long overall path length at a small field angle while minimizing the size of assembly housing necessary to contain the previously recited light reflecting surfaces.

Abstract: A character selector for a shaped beam cathode ray tube comprising an orthogonal pair of air core deflection coils each of which consists of two identical halves formed to fit snugly over the neck of the cathode ray tube. The coils are continuous windings of electrically conductive material and comprise three sections which in operation cause an on-axis electron beam to be sequentially deflected off-axis, converged back to the axis and then referenced along the axis so that the final path of the beam, sequentially deflected on off-axis excursion paths through various shaping apertures in a stencil, is dependent of its off-axis excursion. The character selector may include magnetic material placed over at least a portion of the windings to provide a fine adjustment of the relative magnetic field strength as well as for enhancing the magnetic efficiency and shielding of the device.

Abstract: An electron gun system is described for generating a high current collimated beam of electrons for use in a shaped beam cathode ray tube system. The electron gun includes a cathode having an electron emitting surface for generating free electrons, a collimating grid axially spaced from the cathode and having a central aperture, and a control grid axially spaced from the collimating grid and having a central aperture axially aligned with the aperture of the collimating grid. The control grid receives a varying potential for establishing an electric field which is substantially axial over at least a central portion of the electron beam so as to collimate the beam axially.