Abstract: A billboard or other large display for displaying information has a billboard frame, an artwork layer, and either a plurality of columns of LED light plates or vertical strips of LED lights. The LED plates are small backlight panels formed in an array covering large areas suitable for standard billboards. The LED plates are secured to one another to hang from the billboard frame in separate columns. The columns are situated between the artwork layer and the billboard frame to provide a backlight for the artwork layer. The artwork layer can include two or more layers such that different artwork is displayed depending on the ambient lighting conditions as well as the backlight operation. The LEDs are preferably controlled by a controller to provide desired backlight conditions as well as to display content.

Abstract: A method for producing a large scale color graphic that presents substantially the same spectral content to a viewer when the graphic is illuminated with front or back lighting includes applying an ink film on a first surface and a second ink film on a second surface wherein the ink film creates the desired colored graphic image and which images produced are in registry with one another. A light source located on the same side as an observer viewing the image passes light through the ink film in one direction and is reflected back through the ink in a substantially opposite direction so that light reaching the observer passes through the equivalent of two ink film thicknesses.

Abstract: A military hardware item, such as an aircraft fighter, is simulated in the field by the fabric sheets and light weight plastic panels stored in a cylindrical canister. The canister opens to provide two semi-cylindrical half sections that are laid end-to-end or side-by-side on a black shadow sheet. Imprinted sheets simulate the aircraft's details and are laid over these canister sections. Other aircraft regions are simulated by contoured panels and struts secured to these panels support still other sheets to simulate the aircraft's non-horizontal flight surfaces.

Abstract: An ink jet printing system has a low aspect ratio cylindrical drum adapted to support a sheet of material to be printed by a computer controlled printing head of a plurality of pigmented inks. The drum is preferably of approximately the same diameter as its axial length, is made up of at least two spoked wheel assemblies consisting of several arcuate wheel segment subassemblies that are joined together and held in place by a corregated skin covered with a fiberglass layup to provide a smooth cylindrical surface onto which the sheet material is spread. A clamping device is provided for tensioning the sheet material as it is rotated past a carriage carrying the printing head and affording two relative movement directions as between the printing head and the sheet to be printed for these differently colored printing inks.

Abstract: A clamping device for holding flexible sheet material and the like includes a longitudinally elongated receiving member having a receiving channel across which the sheet material passes. A wedging member breaks the plane of the surface of the sheet material and forces the material into the receiving channel. The receiving member includes a base that intersects with the lower edge of a lip member and the lower edge of a rear wall member that is parallel to and spaced apart from the lip member. The intersection of the respective inner surfaces of the base, rear wall and lip member define the receiving channel wherein the lip member inner surface is inclined toward the inner surface of the rear wall.

Abstract: A hydraulic servomechanism for controlling the pressure of ink supplied to an ink jet printer head includes a bellows located between an ink source and the head and arranged for expansion and contraction to decrease and increase the pressure of ink in the bellows.Pressure is sensed at the bellows output connected to the ink head and the sensed pressure is compared to a desired ink pressure to produce a driving signal which excites an electromagnetic driver coupled to the bellows. The driver applies a force to the bellows to adjust the pressure to the desired pressure. A position sensing switch is responsive to the volume of the bellows and controls a valve located between an ink source and the bellows input to maintain the volume of ink in the bellows within a predetermined volumetric range.

Abstract: Method and apparatus are provided for controlling a group of ink-jet printing heads to selectively apply (or not apply) dots of one color and of substantially fixed size in random dot pattern arrangements to dot positions of a plurality of pixel areas located sequentially along a line scanned by the printing heads. A sequential series of F integral value color image density signals representative of the tone value at which a respective one of the pixel areas is to be printed by the colored dots is produced. A number of different dot pattern arrangements are listed in a table for the F integral values to produce the tone value representative of a density signal of such an integral value. One of the dot pattern arrangements is randomly selected whenever a color density signal of the integral value appears. The group of ink-jet heads apply colored dots onto the dot positions of the associated pixel area in accordance with the pattern randomly selected.