Abstract: A composite structure is provided. The structure includes at least one ply of preimpregnated material formed into a curved elongated member of continuous fibers onto a mandrel. The fibers have a select orientation. The curved elongated member has a length and a cross-sectional geometry that varies along the length.

Abstract: A method and apparatus are provided for forming elongated composite structural members with a desired cross-sectional geometry as taken transverse to the length of the member. An apparatus may include a base with a substantially elongated mandrel mounted thereon. One or more rollers configured to at least partially complementarily engage the mandrel are configured to roll over and press one or more plies of composite material onto the mandrel. The mandrel may be disposed on a rotary table and configured to exhibit a curved elongated geometry to form at least partially curved or arcuate elongated members. The present invention enables the formation of elongated structural members from resin impregnated materials while maintaining the materials in a substantially uncured state. The formed members may then be cocured with a skin or other composite structure.

Abstract: A composite structure is provided. In one embodiment, the structure includes at least one ply of preimpregnated material formed into a curved elongated member of continuous fibers onto a mandrel. The fibers have a select orientation and the curved elongated member has a defined length. The curved elongated member further has a cross-sectional geometry that varies along the length.

Abstract: Method of forming a curved composite structure are provided. In one embodiment, the method includes contacting at least one ply of preimpregnated material on a first surface of a curved mandrel. The first surface of the mandrel has a first radius of curvature. The mandrel further has at least one second surface that has a second radius of curvature. A tension gradient is introduced on the ply adjacent to the first radius of curvature and the ply is then pressed over the curved mandrel to form the curved composite structure.

Abstract: Methods of forming an elongated composite structural member are provided. One method includes, providing a substantially elongated mandrel having an exterior surface exhibiting a desired geometry. Laying up a first ply of preimpregnated fiber reinforced material over the mandrel. Applying a force to the first ply to establish a desired amount of tension within the first ply and then pressing the first ply onto the mandrel in a conformal manner. This includes passing at least one roller over the mandrel and the first ply while maintaining the desired amount of tension within the first ply. The at least one roller is at least partially complementary in shape with the mandrel.

Abstract: Apparatuses, systems and methods for forming elongated composite structural members are provided. One disclosed method includes providing a substantially elongated mandrel having an exterior surface exhibiting a desired geometry. A plurality of plies of fiber material preimpregnated with a thermosetting resin are laid up and pressed onto the mandrel, Pressing the plies of material may include passing one or more rollers over the mandrel and over the plurality of plies along a length of the mandrel, The roller or rollers may be at least partially complementary in shape with the mandrel while maintaining the plies of material in a substantially uncured state during the pressing. The method may include sequentially passing a plurality of rollers over the mandrel and the plies of material. The method may also include configuring a first roller to partially complementarily engage the mandrel and configuring another roller to substantially fully complementarily engage the mandrel.

Abstract: Interferometry apparatus which comprises a measurement light beam (2a, 2b) and a reference light beam (2c, 2d) which interact with each other to cause a spatial fringe pattern (24). An optical device (12) is provided which interacts with the spatial fringe pattern (24), such that light is spatially separated into different directions (30, 32, 34, 36). The intensity modulation in two or more directions of the spatially separated light is phase shifted. The optical device may comprise, for example, a diffractive device, a refractive device or a diffractive optical element.

Abstract: An apparatus for forming elongated composite structural members with a desired cross-sectional geometry as taken transverse to the length of the member. The apparatus may include a base with a substantially elongated mandrel mounted thereon. One or more rollers configured to at least partially complementarily engage the mandrel are configured to roll over and press a plurality of plies of composite material onto the mandrel. The rollers may be configured to form intermediate structures which partially conform to the geometry of the mandrel prior to forming the final structure, which substantially completely conforms to the geometry of the mandrel. The rollers serve to both form and debulk the structure. The present invention enables the formation of elongated structural members from resin-impregnated materials while maintaining the materials in a substantially uncured state. The formed members may then be cocured with a skin or other composite structure.

Abstract: A method and apparatus are provided for forming elongated composite structural members with a desired cross-sectional geometry as taken transverse to the length of the member. An apparatus may include a base with a substantially elongated mandrel mounted thereon. One or more rollers configured to at least partially complementarily engage the mandrel are configured to roll over and press one or more plies of composite material onto the mandrel. The mandrel may be disposed on a rotary table and configured to exhibit a curved elongated geometry to form at least partially curved or arcuate elongated members. The present invention enables the formation of elongated structural members from resin impregnated materials while maintaining the materials in a substantially uncured state. The formed members may then be cocured with a skin or other composite structure.

Abstract: A method and apparatus for forming elongated composite structural members with a desired cross-sectional geometry as taken transverse to the length of the member. An apparatus may include a base with a substantially elongated mandrel mounted thereon. One or more rollers configured to at least partially complementarily engage the mandrel are configure to roll over and press a plurality of plies of composite material onto the mandrel. The rollers may be configured to form intermediate structures which partially conform to the mandrel prior to forming the final structure which substantially completely conforms to the geometry of the mandrel. The rolls serve to both form and debulk the structure. The present invention enables the formation of elongated structural members from resin impregnated materials while maintaining the materials in a substantially uncured state. The formed members may then be cocured with a skin or other composite structure.

Abstract: An optical device which is suitable for use in a projection display comprises a spatial light modulator, such as a liquid crystal device, with a microlens array disposed on its front surface. The microlenses are of convergent type, such as lenticules. The spatial light modulator is of the reflective type and comprises a plurality of rear reflectors, each of which has convergent optical power in at least one direction. The reflectors are arranged such that, for a given direction of illumination, each reflector forms an image of the aperture A of a microlens on the aperture B of another microlens or at a different position on the same microlens. When used in, for example, a projection display, light losses caused by vignetting are reduced.

Abstract: A Liquid crystal device includes: first and second substrates; a layer of liquid crystal disposed between the first and second substrates: and a plurality of picture elements. Each of the picture elements includes: a first electrode disposed on the first substrate; a second electrode electrically insulated from and disposed above the first electrode relative to the substrates; and a third electrode disposed on the second substrate.

Abstract: A dark field projection display includes a light source, a spatial light modulator, and an optical system for directing light from the light source onto the spatial light modulator. The optical system includes a plurality of optical subsystems and a plurality of reflectors. Each of the optical subsystems has an input aperture and is arranged to image light from the light source, the subsystems forming a spatial distribution of source images whose relative positions are different from the relative positions of the input apertures. Each of the optical subsystems further includes a plurality of reflectors disposed at the relative positions of the source images. Each of the reflectors is arranged to reflect light from a respective one of the subsystems onto the spatial light modulator.