Abstract: A partially color corrected projection lens having three groups comprising from the image end a first group serving to correct aberrations, a second group supplying essentially all of the positive power of the lens and a third negative group where the second group comprises two positive elements with a negative element therebetween.

Abstract: A wide angle projection lens which comprises from the image end a first lens unit of negative power having at least one aspheric surface, a second positive lens unit comprising at least two elements and a third negative element having an aspheric concave to the image, where the first lens unit provides negative power to the overall lens and serves as an aberration corrector including some field curvature.

Abstract: A projection lens for a cathode ray tube consisting from the image end of a first lens unit including an element of overall meniscus shape and of positive power at the optical axis, a second lens unit which includes of a biconvex element and supplies the majority of the positive optical power of the lens, the biconvex element being of glass and having spheric surfaces, a third lens unit adjacent the cathode ray tube having a strongly concave image side surface and serving as a field flattener, and a corrector lens unit having at least one aspheric surface, the corrector unit being axially spaced from the second lens unit a distance such that the axial marginal rays from the second lens unit, as traced from the long cojugate intersect the image side surface of the corrector unit at a height from the optical axis that is less than the clear aperture of said corrector lens unit. The corrector lens unit is shaped to correct for off-axis aberrations above the intersection.

Abstract: A filling and weighing system and method for particulate matter in which the particulate matter in powder form is electrically charged and electrically directed to a container on a weight-frequency sensitive balance. The frequency shift of the balance is a measure of the weight of the powder in the container and when a predetermined frequency shift occurs, this is a measure of a predetermined weight of the powder in the container.

Abstract: A zoom lens having a range of equivalent focal lengths (EFL) which extend from a dimension above the diagonal of the film plane of the lens to a telephoto focal length, where the lens comprises three groups of which two are movable to vary the EFL.

Abstract: A projection lens for a cathode ray tube consisting from the image end of a first lens unit including an element of overall meniscus shape and of positive power at the optical axis, the first lens unit has an object side surface convex to the aperture stop, a second lens unit which consists of a biconvex element and supplies the majority of the positive optical power of the lens, the biconvex element beng of glass and having spheric surfaces, a third lens unit adjacent the cathode ray tube having a strongly concave image side surface and serving as a field flattener, the axial spacing between the first lens unit and said second lens unit also contributing to correction of field curvature, and a corrector lens unit having image side surface convex toward the aperture stop. The surfaces of the first lens unit and the corrector lens unit which are both convex to the aperture stop contribute to correction of sagittal oblique spherical aberration.

Abstract: A strap wrench adapted to fit about an object having a connection to another object, so that the connection may be tightened or loosened, comprising a flexible strap having an end attached to a securing member and a free end which is received in a securing member which provides infinite adjustment of the periphery of the strap and retains the strap at a predetermined size determined by the circumference of the object to be turned, a wrenching member is pivotally connected to the securing member and the wrenching member has a shape defining a corner or projection for bearing on the strap and exerting a force thereon when the wrenching member is rotated by a turning tool inserted therein.

Abstract: An automatic focusing zoom lens which comprises a first positive group, a second variator group, a third compensator group, and a relay lens including an autofocus detector which receives a portion of the light entering the fourth group and controls a motor which drives the compensator group to maintain focus of the lens as well as compensating or the shift in focal plane due to movement of the variator group to change the equivalent focal length of the lens.

Abstract: A teaching system utilizing prerecorded tape which is prepared in sectors with a message segment and position indicators in the form of transparent windows which are photoelectrically detected. After a message or question is played, a first window is detected by a first detector and the tape drive motor is deenergized with another window positioned before one of a plurality of other detectors. The operator then attempts to answer or identify the message by making a selection corresponding to one of the plurality of detectors, and if a correct answer is given, a signal is given to the operator. All of the photoelectric detecting devices are on a carrier which is removably mounted to a cassette.

Abstract: An elevated display ramp for an automotive vehicle constructed of parallel hollow rods in joinable sections where adjoining sections are aligned through common nipples and tabs and joined rods are locked together to securely and safely lock elevated sections together. The elevated sections are supported on trestles of varying height which determine the angle of the elevated sections.

Abstract: A boom for spraying equipment comprises at least one elongate member having an outer skin over a core of a material having a lower density than the skin. The core material may occupy all of the space within the outer skin or the elongate member may be hollow, at least part of a side wall of the member being formed of an outer skin, an inner skin and core material sandwiched between the inner and outer skins. The outer skin and the core material may be metallic or non-metallic, suitably a fibre reinforced plastics material. There may be a plurality of elongate members which are mutually spaced, parallel arranged and extend in a direction lengthwise of the boom.

Abstract: A pick for a stringed instrument having a finger gripping portion and a picking portion where the thumb side gripping is formed with a generally rectangular recess and the forefinger gripping side is a generally rectangular slot having a nominal center line forming a substantial transverse angle with the length of the thumb gripping portion.

Abstract: A projection lens for a cathode ray tube display which comprises from the image end a first lens unit of relatively weak optical power serving primarily to correct aperture dependent aberrations, a second lens unit of strong positive power permitting decreased equivalent focal length and resulting wide field angle, and a third lens unit having a strongly concave image side surface and serving to correct the Petzval curvature of the surfaces of the other lens units. The second lens unit comprises two elements of overall biconvex shape separated by an air gap. The facing surfaces of the two elements of the second lens unit are of relatively weak optical power and at least one of the surfaces of the two elements of the second lens unit is aspheric to contribute to the corrections provided by said second lens unit.

Abstract: A projection lens for a cathode ray tube display which comprises from the image end, a first group of relatively weak optical power serving primarily to correct aperture dependent aberrations, a second group of strong positive power, and a third negative group having a strongly concave image side surface and which serves as a field flattener and to correct the Petzval curvature of the services of the elements of the other groups. The second group comprises two elements which provide substantially all of the positive power of the lens and which define an air meniscus therebetween with the minor dimension at the optical axis. The optical powers of the second group bear a predetermined ratio and have a minor dimension at the optical axis.

Abstract: A compact projection lens for a cathode ray tube having a field angle as great as 73.degree. which may utilize only three lens elements where the first lens element from the image side has two aspheric surfaces in the shape of an overall meniscus which goes from positive optical power at the optical axis to relatively strong negative optical power at the limit of the clear aperture of the lens. The spacing between the first and second lens elements is chosen to aid in contributing to correction of field curvature.

Abstract: A projection lens system adapted to project an image from a cathode ray tube and consisting from the image end of a first lens unit of weak optical power, a second lens unit of strong optical power including a biconvex glass element, a third lens unit of strongly negative optical power having a convex image side surface and serving as a field flattener, the first lens unit consisting of a first meniscus shaped element having positive power at the optical axis having at least one aspheric surface and being convex to the image, and a second meniscus shaped element having at least one aspheric surface, the said second meniscus being convex to the second lens group and closely spaced thereto. The second meniscus may be on either side of the second lens unit and is of very weak optical power.

Abstract: A zoom lens having a range of equivalent focal lengths extending from a range below the dimension of the diagonal of the image frame to a dimension substantially above and having a zooming range of up to six to one or greater where the lens has a plus, minus, plus, plus lens unit configuration with a strongly negative second lens unit and a fourth lens unit designed to have a given power and telephoto ratio to compensate for a remote aperture stop located in the third lens unit.

Abstract: A lens of variable equivalent focal length where two lens groups located on either side of an aperture defining means move relative to the aperture defining means, and a lens group of positive power is positioned close to the aperture defining means. The aperture defining means and the associated positive power group may either be stationary or move with change in equivalent focal length.