Abstract: A centraliser comprises longitudinally spaced collars connected by a plurality of springs, each of the springs comprising two or more bow sections.

Abstract: A lens system is presented having a diffractive optical power region. The diffractive optical power region has a plurality of concentric surface relief diffractive structures. A greater portion of light incident on a diffractive structure near the center point contributes to the optical power than light incident on a diffractive structure peripherally spaced therefrom.

Abstract: A lens system is presented having a diffractive optical power region. The diffractive optical power region has a plurality of concentric surface relief diffractive structures. A greater portion of light incident on a diffractive structure near the center point contributes to the optical power than light incident on a diffractive structure peripherally spaced therefrom.

Abstract: A drainage collection box device for automatically removing leaves and other debris from a collection box of a drainage system. The drainage collection box device includes a container having a base, an open upper end, one or more sidewalls, and one or more openings disposed on the sidewalls. Each opening of the container can be connected to a pipe of a drainage system, wherein water and debris travel into the container therefrom. The device further includes a lid pivotally secured to the upper end of the container and a pair of baffles disposed on the sides of the lid. As the water level rises to the top of the container, the pressure from the rising water and debris push the lid to an open configuration, wherein the baffles direct the water and debris to flow out of the front upper end of the container.

Abstract: Embodiments of the present invention relate to a multifocal lens having a diffractive optical power region and a progressive optical power region. Embodiments of the present invention provide for the proper alignment and positioning of each of these regions, the amount of optical power provided by each of the regions, the optical design of the progressive optical power region, and the size and shape of each of the regions. The combination of these design parameters allows for an optical design having less unwanted astigmatism and distortion as well as both a wider channel width and a shorter channel length compared to conventional PALs. Embodiments of the present invention may also provide a new, inventive far-intermediate distance zone and may further provide for increased vertical stability of vision within a zone of the lens.

Abstract: Embodiments of the present invention relate to a multifocal lens having a mostly spherical power region and a progressive optical power region. Embodiments of the present invention provide for the proper alignment and positioning of each of these regions, the amount of optical power provided by each of the regions, the optical design of the progressive optical power region, and the size and shape of each of the regions. The combination of these design parameters allows for an optical design having less unwanted astigmatism and distortion as well as both a wider channel width and a shorter channel length compared to conventional PALs. Embodiments of the present invention may also provide a new, inventive far-intermediate distance zone and may further provide for increased vertical stability of vision within a zone of the lens.

Abstract: A lens system is presented having a diffractive optical power region. The diffractive optical power region has a plurality of concentric surface relief diffractive structures. A greater portion of light incident on a diffractive structure near the center point contributes to the optical power than light incident on a diffractive structure peripherally spaced therefrom.

Abstract: Embodiments of the present invention relate to a multifocal lens having a mostly spherical power region and a progressive optical power region. Embodiments of the present invention provide for the proper alignment and positioning of each of these regions, the amount of optical power provided by each of the regions, the optical design of the progressive optical power region, and the size and shape of each of the regions. The combination of these design parameters allows for an optical design having less unwanted astigmatism and distortion as well as both a wider channel width and a shorter channel length compared to conventional PALs. Embodiments of the present invention may also provide a new, inventive far-intermediate distance zone and may further provide for increased vertical stability of vision within a zone of the lens.

Abstract: Embodiments of the present invention relate to a multifocal lens having a diffractive optical power region and a progressive optical power region. Embodiments of the present invention provide for the proper alignment and positioning of each of these regions, the amount of optical power provided by each of the regions, the optical design of the progressive optical power region, and the size and shape of each of the regions. The combination of these design parameters allows for an optical design having less unwanted astigmatism and distortion as well as both a wider channel width and a shorter channel length compared to conventional PALs. Embodiments of the present invention may also provide a new, inventive far-intermediate distance zone and may further provide for increased vertical stability of vision within a zone of the lens.

Abstract: Aspects of the present invention provide multiple-layer (multi-layer) composite lenses comprising two or more materials and methods for making the same. A multi-layer composite lens of the present invention can use multiple surfaces (internal or external) to form optical elements that can contribute to a total desired add power. The multiple contributing optical elements can be aligned so as to be in optical communication to form multiple stable vision zones to enhance optical performance and the vision experience of the wearer. Distributing the total desired add power across multiple appropriately aligned optical elements that are in optical communication with one another can reduce the total distortion of the lens, minimize the number of optical discontinuities introduced, can reduce optical power jump as experienced by the wearer's eye when traversing any discontinuity, and can reduce the visibility of any introduced optical discontinuity as perceived by an observer looking at the wearer.

Abstract: Embodiments of the present invention relate to a multifocal lens having a mostly spherical power region and a progressive optical power region. Embodiments of the present invention provide for the proper alignment and positioning of each of these regions, the amount of optical power provided by each of the regions, the optical design of the progressive optical power region, and the size and shape of each of the regions. The combination of these design parameters allows for an optical design having less unwanted astigmatism and distortion as well as both a wider channel width and a shorter channel length compared to conventional PALs. Embodiments of the present invention may also provide a new, inventive far-intermediate distance zone and may further provide for increased vertical stability of vision within a zone of the lens.

Abstract: Aspects of the present invention provide multiple-layer (multi-layer) composite lenses comprising two or more materials and methods for making the same. A multi-layer composite lens of the present invention can use multiple surfaces (internal or external) to form optical elements that can contribute to a total desired add power. The multiple contributing optical elements can be aligned so as to be in optical communication to form multiple stable vision zones to enhance optical performance and the vision experience of the wearer. Distributing the total desired add power across multiple appropriately aligned optical elements that are in optical communication with one another can reduce the total distortion of the lens, minimize the number of optical discontinuities introduced, can reduce optical power jump as experienced by the wearer's eye when traversing any discontinuity, and can reduce the visibility of any introduced optical discontinuity as perceived by an observer looking at the wearer.

Abstract: Aspects of the present invention provide multiple-layer (multi-layer) composite lenses comprising two or more materials and methods for making the same. A multi-layer composite lens of the present invention can use multiple surfaces (internal or external) to form optical elements that can contribute to a total desired add power. The multiple contributing optical elements can be aligned so as to be in optical communication to form multiple stable vision zones to enhance optical performance and the vision experience of the wearer. Distributing the total desired add power across multiple appropriately aligned optical elements that are in optical communication with one another can reduce the total distortion of the lens, minimize the number of optical discontinuities introduced, can reduce optical power jump as experienced by the wearer's eye when traversing any discontinuity, and can reduce the visibility of any introduced optical discontinuity as perceived by an observer looking at the wearer.

Abstract: Embodiments of the present invention relate to a multifocal lens having a diffractive optical power region and a progressive optical power region. Embodiments of the present invention provide for the proper alignment and positioning of each of these regions, the amount of optical power provided by each of the regions, the optical design of the progressive optical power region, and the size and shape of each of the regions. The combination of these design parameters allows for an optical design having less unwanted astigmatism and distortion as well as both a wider channel width and a shorter channel length compared to conventional PALs. Embodiments of the present invention may also provide a new, inventive far-intermediate distance zone and may further provide for increased vertical stability of vision within a zone of the lens.

Abstract: Embodiments of the present invention relate to a multifocal lens having a mostly spherical power region and a progressive optical power region. Embodiments of the present invention provide for the proper alignment and positioning of each of these regions, the amount of optical power provided by each of the regions, the optical design of the progressive optical power region, and the size and shape of each of the regions. The combination of these design parameters allows for an optical design having less unwanted astigmatism and distortion as well as both a wider channel width and a shorter channel length compared to conventional PALs. Embodiments of the present invention may also provide a new, inventive far-intermediate distance zone and may further provide for increased vertical stability of vision within a zone of the lens.

Abstract: A pressure relief bursting disc has a flange portion, a sloping portion interior of the flange portion and a dished portion interior of the sloping portion. The sloping portion has its wider end joined to the flange portion and slopes up from the flange portion in a first direction and is joined at its narrower end directly to the dished portion. The dished portion has its concave side facing in the first direction. In use pressure is applied to the concave side of the dished portion. The disc has a line of weakness, in the sloping portion. This shape achieves reliability of the burst strength, because the sloping portion buckles at the burst strength.

Abstract: Embodiments of the present invention relate to a multifocal lens having a diffractive optical power region and a progressive optical power region. Embodiments of the present invention provide for the proper alignment and positioning of each of these regions, the amount of optical power provided by each of the regions, the optical design of the progressive optical power region, and the size and shape of each of the regions. The combination of these design parameters allows for an optical design having less unwanted astigmatism and distortion as well as both a wider channel width and a shorter channel length compared to conventional PALs. Embodiments of the present invention may also provide a new, inventive far-intermediate distance zone and may further provide for increased vertical stability of vision within a zone of the lens.

Abstract: Aspects of the present invention provide multiple-layer (multi-layer) composite lenses comprising two or more materials and methods for making the same. A multi-layer composite lens of the present invention can use multiple surfaces (internal or external) to form optical elements that can contribute to a total desired add power. The multiple contributing optical elements can be aligned so as to be in optical communication to form multiple stable vision zones to enhance optical performance and the vision experience of the wearer. Distributing the total desired add power across multiple appropriately aligned optical elements that are in optical communication with one another can reduce the total distortion of the lens, minimize the number of optical discontinuities introduced, can reduce optical power jump as experienced by the wearer's eye when traversing any discontinuity, and can reduce the visibility of any introduced optical discontinuity as perceived by an observer looking at the wearer.

Abstract: A lens system is presented having a diffractive optical power region. The diffractive optical power region has a plurality of concentric surface relief diffractive structures. A greater portion of light incident on a diffractive structure near the center point contributes to the optical power than light incident on a diffractive structure peripherally spaced therefrom.

Abstract: Embodiments of the present invention relate to a multifocal lens having a diffractive optical power region and a progressive optical power region. Embodiments of the present invention provide for the proper alignment and positioning of each of these regions, the amount of optical power provided by each of the regions, the optical design of the progressive optical power region, and the size and shape of each of the regions. The combination of these design parameters allows for an optical design having less unwanted astigmatism and distortion as well as both a wider channel width and a shorter channel length compared to conventional PALs. Embodiments of the present invention may also provide a new, inventive far-intermediate distance zone and may further provide for increased vertical stability of vision within a zone of the lens.