Hughes Aircraft Company

Raytheon Company

Hughes Electronics Corporation

Gary R Noyes

James J Carlson

John Steven Anderson

Ashok B Patel

Pan-Fey F Chen

A single aperture opto-mechanical system for transmitting two small-aperture laser beams and single received laser beam. The two pencil-thin transmitted beams are co-aligned within 150 micro-radians in the same direction but have optical axes that are displaced laterally. An in-coming beam is received along a path that is essentially parallel with the path of the transmitted beams within 500 micro-radians. The small-aperture transmitted beams each pass through a hole in a metal mirror beamsplitter that is positioned to reflect the received light energy at a 90 E angle through a narrow band-pass filter and focused by an aspheric glass lens that directs the received beam energy onto a receiver detector. The beamsplitter has indexing features that provide self-alignment of the beamsplitter to the laser mount.

Displaced aperture beamsplitter for laser transmitter/receiver

The focal length of an objective lens system is substantially equal at two wavelengths: one within the visible spectrum and one within an eyesafe IR spectrum centered about 1.54 .mu.m; the lens is essentially achromatic throughout the entire visible spectrum (0.45 .mu.m -0.70 .mu.m) and is well-corrected for other monochromatic aberrations (spherical aberration, coma, astigmatism, field curvature, and distortion). By having an objective lens that is common to both optical paths (visual and laser) and has the property of having essentially the same focal length and essentially the same angular deviation for the two optical paths upon lens decentration, then a practical mechanism can be included in the opto-mechanical design of a laser rangefinder to adjust the x and y decentration of the objective lens to accomplish a corresponding x and y adjustment of the system boresight. One specific embodiment is a cemented triplet in which the front lens element is bi-convex and is formed of a crown glass having a relatively high index of refraction (n) and a moderately high inverse relative dispersion (V); the rear element is substantially plano convex and is formed of a crown glass having a relatively low index of refraction and a relatively high inverse relative dispersion; and the middle lens element is bi-concave and is formed of an anomalous dispersion flint glass having an index of refraction intermediate that of the front and rear elements and an inverse relative dispersion that is substantially below that of those other two elements, with partial relative dispersion being displaced from the 'normal' line by at least twice and preferably at least six times the distance associated with the normal glasses forming the two convergent elements.

Constant deviation objective lens

An imaging system (10) contains a diffractive optic lens (14) which allows for a relatively accurate representation of objects within a field of view. These objects are associated with light rays (20, 22 and 24) which are made to impinge upon the diffractive optic lens (14) and thereafter are made to be received by an imaging surface (12) at a receiving angle which may be determined by the structure of the diffractive optic lens (14). The diffractive optic lens (14) may be placed within the typical dewar (16) of the image acquisition system (10), may be removable deployed over the imaging surface (12), or alternatively, the diffractive optic lens may be etched upon the front side of the imaging surface (12) by the use of standard etching techniques such as lithography, diamond turning and the like.

Binary optic imaging system

A portable missile launcher has an optical system with a single lens (22) for receiving visible and near infrared light energy from a target (14) directing it to a prism (24) where the light is split into a part transmitted to an eyepiece (28) and a further part (30) to infrared tracking equipment (18). The objective lens (22) is a doublet having a front lens (32) and a rear lens (41) which cooperate to provide sufficiently small chormatic aberration to enable image quality correction for both visual examination and near infrared tracking.

Objective lens assembly for a portable missile launcher

An optical system (10) for portable missile launcher (23) includes an objective lens (12) for receiving the entire visual and near infrared light energy emanating from a target (14) and immediate background of the target. The light energy from the objective lens then passes through a Porro prism assembly (16) which acts to direct visual light along a first path to an eyepiece (20) and near infrared along a second path at approximately a right angle to the first path where it is received by a tracker assembly (22) and monitored. The Porro prism (16) is constructed in accordance with this invention to include a multi-layer interference dichroic coating (18) disposed between the two prisms (34,36) which make up the prism assembly. This coating is of such a nature as to readily permit light energy in the visual range to pass directly through the coating, but at the same time to reflect the near infrared components along a second path bringing them to focus on the tracker assembly (22).

Optical viewing and near infrared tracking system for a portable missle

There is disclosed an afocal zoom lens attachment of variable magnification which is intended for use with a prime imaging lens of fixed focal length and which is particularly suited for systems using radiation having a wavelength in the infrared region of the spectrum. The attachable zoom lens system is comprised of a fixed focus front objective element and a fixed focus eyepiece with a zooming doublet and a zooming singlet therebetween and is configured to form a mechanically compensated, non-Galilean afocal zoom attachment. The system includes means for continuously varying the magnification by simultaneously moving the zooming singlet and doublet along linear and non-linear paths respectively. The doublet contains a color correcting element. A real intermediate aerial image is formed between the zooming singlet and the eyepiece at low magnifications and that image is recollimated by the eyepiece. During zooming to higher magnifications the singlet may move through the plane of the real image thereby moving its plane to contribute to aberration correction. In preferred embodiments the lens system is used as an attachment to a prime thermal imaging device and each of the lenses has a useful spectral bandpass for energy in the 2-20 micron region of the infrared spectrum.

Growing community of inventors

Los Angeles, CA, United States of America

Gary R Noyes