The present invention relates to target acquisition and related devices, and more particularly to telescopic gunsights and associated equipment used to achieve shooting accuracy at, for example, close ranges, medium ranges and extreme ranges at stationary and moving targets.

Apparatus and method for calculating aiming point information

A CCD imager whose sampling structure is loosely modeled after the biological visual system is described. Its architecture and advantages over conventional cameras for pattern recognition are discussed. The sensor has embedded in its structure a logarithmic transformation that makes it size and rotation invariant. Simulations on real images using the actual sensor geometry have been performed to study the sensor performance for 2D pattern recognition and object tracking.

A Foveated Retina-Like Sensor Using CCD Technology

A modified Mellin transform for digital implementation is developed and applied to range radar profiles of naval vessels. The scale invariance property of the Mellin transform provides a means for extracting features from the profiles which are insensitive to the aspect angle of the radar. Past implementations of the Mellin transform based on the FFT have required exponential sampling, interpolation, and the computation of a correction term, all of which introduce errors into the transform. In addition, exponential sampling results in a factor of ln N increase in the number of data points. An alternate implementation, developed in the paper, utilizes a direct expansion of the Mellin integral definition. This direct Mellin transform (DMT) eliminates the implementation problems associated with the FFT approach, and does not increase the number of samples. A scale and translation invariant transform is developed from a modification of the DMT. The MDMT applied to the FFT of the radar profiles results in the desired insensitivity without having the low-pass filtering characteristic that exists in other Fourier-Mellin implementations.

A New Implementation of the Mellin Transform and its Application to Radar Classification of Ships

An improved telescopic gunsight is provided by combining a conventional telescopic gunsight with a reticle having a primary vertical cross-hair, a primary horizontal cross-hair intersecting the primary vertical cross-hair, a plurality of secondary horizontal cross-hairs having predetermined thickness evenly spaced a predetermined distance along the primary vertical cross-hair, a plurality of secondary vertical cross-hairs having predetermined thickness evenly spaced a predetermined distance along at least some of the secondary horizontal cross-hairs and an optical range-finder for quickly determining the range to the intended target Some of the secondary horizontal cross-hairs are marked with a unique identifying character to assist the shooter in quickly finding an aiming point The thickness of, and spacing between, the cross-hairs can be based upon an easy to learn inches of angle (or centimeters of angle) scale, or upon any other conventional scale, which can be the same or different from the scale used for the rangefinder The rangefinder can be formed from vertical and horizontal arms The vertical rangefinder arm can be superimposed over the primary vertical cross-hair and the horizontal rangefinder arm can be superimposed over the primary horizontal cross-hair as desired to provide a clearer field of vision

Gunsight and reticle therefor

An improved shooting system is provided by using a firearm having a telescopic gunsight mounted a predetermined distance above the barrel in conjunction with a computer including a controller, memory; a program stored in memory for calculating targeting information. The computer can be a hand-held, personal digital assistant type device which enables the user to input information regarding weather, gun and ammunition characteristics, and target information, including range to target, and which quickly calculates the adjustments which need to be made to a conventional scope, or the location on the reticle which should be used as an aiming point, in order to hit the target.

Apparatus and method for calculating aiming point information for rifle scopes

A reticle plate provided with a reticle and three concentric circles of ving diameter and methods of use thereof, the invention allows a user to establish a north-oriented or south-oriented line by alignment of selected circumpolar stars with the circles. The circles are located on the reticle plate in positions determined by angles which exist between the celestial north (or south) pole and the particular low-magnitude circumpolar stars chosen as sighting points, the radii of the circles being directly proportional to the objective lens focal length of the theodolite or optical instrument within which the plate is used. A first method of the invention allows unambiguous location of the north or south pole by alignment of each of three selected stars with one each of the three circles. A second method provides data to a user sufficient to locate the pole by alignment of innermost and outermost circles respectively with one each of two of the selected stars.

Reticle plate and method for establishment of a north-oriented or south-oriented line by circumpolar orientation

A clarification on the use of the Mellin transform in optical pattern recognition

An apparatus for performing an incoherent optical Fourier transform inclu a source of incoherent light, means for generating and phase modulating a first zone plate, a second zone plate, means for detecting incoherent light processed by the apparatus, and means for filtering the output signal, thereby discriminating between the Fourier transform signal and background constant or bias signals. A method for performing incoherent optical Fourier transform is also disclosed.

Incoherent optical heterodyne Fourier transformer

The suitability of holography as a method for recording and reproducing visual displays of terrain is examined in a tutorial, non-mathematical manner. The paper is based chiefly on a literature search combined with some original work by the author. Consideration of requirements for 3-D displays in general and the particular problem of making holograms of terrain is followed by a detailed discussion of the different types of hologram and how they may be used to make terrain displays with different characteristics. Emphasis is on the 2-photograph stereoscopic hologram which is called a "holographic stereomodel". Techniques to enhance certain characteristics of holographic displays such as color rendition and efficient use of illumination are examined and possible uses of holography in tasks related to map making are suggested. A discussion of the advantages and disadvantages of selected types of holograms for terrain display is included.

Holographic Terrain Displays

(1997). Proof Without Words: Construction of Two Lunes with Combined Area Equal to That of a Given Right Triangle. Mathematics Magazine: Vol. 70, No. 5, pp. 380-380.

Michael M. McDonnell

Papers

Reticle plate and method for establishment of a north-oriented or south-oriented line by circumpolar orientation

A clarification on the use of the Mellin transform in optical pattern recognition

Incoherent optical heterodyne Fourier transformer

Holographic Terrain Displays

Proof Without Words: Construction of Two Lunes with Combined Area Equal to That of a Given Right Triangle