摘要:
An optical system transmits a first radiation beam along a first axis and receives a reflected beam along that axis; the first beam having a first wavelength and a p-planar polarization; the second beam having the first wavelength, a p-planar polarized component, an s-planar polarized component, and a greater cross-sectional area than the first beam. The system includes a transmit/reflect mirror positioned at a 45.degree. to the first axis and free of apertures in its optical area, a radiation source, an element for directing radiation from the source along the first axis toward the mirror; an element for directing radiation outwardly from the mirror along the first axis, and for directing the second beam along the first axis toward the mirror. An antireflection coating on the primary side of the mirror passes radiation having the first wavelength and a p-planar polarization. An inner area of a coating on the secondary side of the mirror passes substantially all of the p-planar polarization radiation while reflecting s-planar polarization radiation. An outer area of the secondary coating reflects substantially all radiation incident thereon having the first wavelength.
摘要:
A missile guidance system including a sensor for detecting the position of a target and for detecting the position of a missile. A fire control processor is provided that computes a trajectory for the missile to the target and is connected to the sensor to determine any variations between the actual missile position from a computed trajectory missile position. A transmitter connected to this guidance computer then provides guidance information to the missile. The guidance information includes the missile position relative to the target and enables a processor on board the missile to recompute a new trajectory to the target. This guidance information is transmitted as a single pulse during a predetermined time interval as a periodic update to the missile.
摘要:
A method and apparatus are provided for mounting a circuit component such as a gate array device 12 on a printed circuit board 14. The component 12 may include a plurality of pin-type electrical contacts 18 wherein a first portion of the pin-type contacts 18 have been replaced by button-type contacts. In one embodiment, at least two of the pin-type contacts 22, 24 have been retained and serve the dual purpose of locating the gate array device 12 on the printed circuit board 14 and attaching the gate array device 12 to the printed circuit board 14. A sheet of boron nitride 26 is positioned between the printed circuit board 14 and the circuit component, e.g., the gate array device 12. The sheet of boron nitride 26 includes a plurality of openings extending therethrough in a pattern corresponding to the pattern of electrical contacts 18 on the gate array device 12. The openings 32 in the sheet of boron nitride 26 that correspond to the button-type contacts have resilient electrical contacts 34 disposed therein. The printed circuit board 14 includes a plurality of pad-type contacts 40 disposed on a surface thereof in a pattern corresponding to the button-type contacts of the gate array device 12.
摘要:
A gimballed optical system within a seeker head includes a relatively low power laser coupled to a relatively higher power laser by way of a flexible fiber optic cable to reduce the mass that must be oscillated in a scan.
摘要:
Fiber reinforced composite products of enhanced interlaminar ply strength and processes of producing same. In forming the products, layers of fibrous reinforcing material and resinous matrix material are established. The matrix material contains unset resin and short fibers of an average particle length of 0.2-0.6 mm in a weight ratio of short fibers to resin in the range of 0.4-1. The reinforcing material comprises fibers of a length substantially greater than the length of the short fibers in the matrix material. The fiber and matrix layers are integrated in order to cause the resin and short fibers which comprise the strengthened matrix material to enter into the interstitial spaces of the longer fiber reinforcing material. Thereafter, the matrix resin is solidified in order to arrive at the fiber reinforced composite product. Alternate fiber and matrix layers may be built up on a surface while a pressure gradient is established from the outside of the built up layers to the surface in order to cause the resin to flow across the interfacial boundaries of the resin and fiber layers. The flow across the resin fiber interfaces promotes orientation of the short fibers in a direction across the interfaces so that the short fibers enter into the interstitial spaces between the reinforcing fibers.
摘要:
A broadband absorber for absorbing a broad spectrum of incident microwave radiation is provided comprising a plurality of strips of inductive absorbing material having magnetic particles dispersed throughout an organic binder; the width, thickness, and composition of the strips being selected such that each strip absorbs a specific region of the microwave spectrum. The plurality of strips of absorbing material are supported by a substrate that is electrically conductive to microwave radiation. The substrate has a plurality of grooves and ridges in a repeating pattern, the grooves being of varying depths. A facing sheet, electrically transparent to microwave radiation, is provided for coupling the incident microwave radiation to the plurality of strips of inductive absorbing material.
摘要:
In accordance with the invention, compositions of matter are provided for forming two coatings for protecting carbonaceous substrates from degradation at elevated temperatures and to improve said substrate's resistance to surface crazing and cracking. Preferably, the compositions are a mixture of particulate silicon, silicon carbide, alumina and boron. Preferably, the primary mixture contains between about 40% and 50% silicon by weight of the total composition, between about 30% and 50% silicon carbide by weight of the total composition, and between about 20% and 30% alumina by weight of the total composition. Preferably, the secondary mixture contains between about 25% and 40% silicon by weight of the total composition, between about 50% and 70% silicon carbide by weight of the total composition, between about 1% and 15% boron by weight of the total composition, and a minor amount of magnesium oxide. The method is provided for forming a primary protective coating on carbonaceous substrates utilizing the aforesaid primary and secondary mixtures.
摘要:
A system for transforming a first 3-D image of a target scene obtained from reflected energy signals to create a second 3-D image from a different perspective. In an illustrative embodiment, the original image includes multiple data elements stored in addresses of a row-column array, where each data element comprises a range and an intensity value corresponding to a point in the target scene. Each data element may be addressed by selecting its row and column numbers. To create the new image, each data element's row-column address is first converted into a spherical coordinate. The spherical coordinate is then converted into a 3-D Cartesian coordinate, and the Cartesian coordinate is translated and rotated to achieve the new perspective. The translated, rotated, Cartesian coordinate is then converted back into a spherical coordinate, and then into row-column format. Then, the contents of each data element of the original array are stored in the new array, in the newly calculated address. A "hidden surface" algorithm may be employed to remove images corresponding to surfaces that are blocked or "hidden" when viewed from the new perspective. This is accomplished by filling unused addresses of the new array with range and intensity values calculated to match that of a background plane.
摘要:
An improved system for using reflected energy signals sensed by light detecting optics to identify flat surfaces that are orthogonal to the detecting optics. A light source generates a laser light beam, the beam is scanned across a target scene, and a reflected signal is sensed by light detecting optics to produce an electrical representation of the reflected signal. The representation is stored in an array in the form of a plurality of data elements. The data elements are sequentially analyzed by comparing the range of each data element with the ranges of a selected number of neighboring elements, and giving the data element under analysis a corresponding "index." Data elements whose ranges closely match neighboring data elements are assigned higher indices. Neighboring data elements with high indices therefore signify proximate points on a flat surface, which is orthogonal to the detecting optics. The data elements may be further analyzed by distinguishing elements with higher indices from those with lower indices, to highlight the flatter, more orthogonal surfaces.
摘要:
A growth vessel (10) comprises a crucible (12) for containing the source materials within its cavity (26), a substrate carrier (15, 115) positioned on inner shoulder 27 of the crucible sidewalls (22-25), a source tray (14) positioned within the crucible cavity (26), at least one spacer (13) positioned between the bottom of the crucible cavity (26) and the source tray (14), a substrate carrier (15, 115) positioned within the crucible cavity (26) for mounting a substrate parallel to the source of growth material in the source tray (14), and a crucible lid (17, 117).