Abstract: Optical lens attachments and cameras are disclosed. The attachment comprises a coupling mechanism for mating engagement with at least one of a camera and an optical lens. A barrel is coupled at one end to the coupling mechanism. A negative lens unit is coupled to the other end of elongated barrel. A diopter lens is disposed between the barrel and the coupling mechanism. The coupling mechanism, the diopter lens, and the barrel are aligned with an optical axis. Also disclosed is a double swivel optical system, comprising a negative lens unit, a mirror oriented at an angle to the optical axis of the negative lens unit, a roof prism for rotating incident light rays by 90 degrees and inverting an image, a rotation mechanism permitting rotation of the negative lens unit about a vertical axis, an image rotator comprising a prism that can invert an image, the prism disposed within the image rotator, and another rotation mechanism permitting rotation of the roof prism about an optical axis of the image rotator.

Abstract: Optical lens attachments and cameras are disclosed. The attachment comprises a coupling mechanism for mating engagement with at least one of a camera and an optical lens. A barrel is coupled at one end to the coupling mechanism. A negative lens unit is coupled to the other end of elongated barrel. A diopter lens is disposed between the barrel and the coupling mechanism. The coupling mechanism, the diopter lens, and the barrel are aligned with an optical axis. Also disclosed is a double swivel optical system, comprising a negative lens unit, a mirror oriented at an angle to the optical axis of the negative lens unit, a roof prism for rotating incident light rays by 90 degrees and inverting an image, a rotation mechanism permitting rotation of the negative lens unit about a vertical axis, an image rotator comprising a prism that can invert an image, the prism disposed within the image rotator, and another rotation mechanism permitting rotation of the roof prism about an optical axis of the image rotator.

Abstract: Optical lens attachments and cameras are disclosed. The attachment comprises a coupling mechanism for mating engagement with at least one of a camera and an optical lens. A barrel is coupled at one end to the coupling mechanism. A negative lens unit is coupled to the other end of elongated barrel. A diopter lens is disposed between the barrel and the coupling mechanism. The coupling mechanism, the diopter lens, and the barrel are aligned with an optical axis. Also disclosed is a double swivel optical system, comprising a negative lens unit, a mirror oriented at an angle to the optical axis of the negative lens unit, a roof prism for rotating incident light rays by 90 degrees and inverting an image, a rotation mechanism permitting rotation of the negative lens unit about a vertical axis, an image rotator comprising a prism that can invert an image, the prism disposed within the image rotator, and another rotation mechanism permitting rotation of the roof prism about an optical axis of the image rotator.

Abstract: Wide-angle, deep-field, close-focusing optical systems are disclosed. According to one aspect, the optical system comprises a negative lens unit and a relay lens. The negative lens unit accepts radiation from an object in space. The relay lens is coupled to the negative lens unit. The negative lens unit and the relay lens are aligned on an optical axis in that order. The negative lens unit forms a first image on the relay lens to form a final image at a final image plane at a distance from the relay lens. The relay lens may comprise a zoom lens or zoom lens components, which may be movable.

Abstract: Wide-angle, deep-field, close-focusing optical systems are disclosed. According to one aspect, the optical system comprises a negative lens unit and a relay lens. The negative lens unit accepts radiation from an object in space. The relay lens is coupled to the negative lens unit. The negative lens unit and the relay lens are aligned on an optical axis in that order. The negative lens units forms a first image on the relay lens to form a final image at a final image plane at a distance from the relay lens. The relay lens may comprise a zoom lens or zoom lens components, which may be movable.

Abstract: Wide-angle, deep-field, close-focusing optical systems are disclosed. According to one aspect, the optical system comprises a negative lens unit and a relay lens. The negative lens unit accepts radiation from an object in space. The relay lens is coupled to the negative lens unit. The negative lens unit and the relay lens are aligned on an optical axis in that order. The negative lens units forms a first image on the relay lens to form a final image at a final image plane at a distance from the relay lens. The relay lens may comprise a zoom lens or zoom lens components, which may be movable.

Abstract: Lenses comprising first and second walls defining a cavity therebetween, which contains a fluid, are described. At least one of the walls is flexible, and the amount of fluid in the cavity can be changed to alter the shape of the at least one flexible wall, so as to alter the power of the lens. One or more flexible walls may have at least one groove formed in the wall(s) close to the periphery(ies) of the wall(s). In yet another configuration, the flexible wall and the second wall are bonded, welded, or fused together. In yet another configuration, a lens comprises a flexible wall and a second wall. The flexible wall is resilient and thinner in its central region, which is capable of being displaced relative to the second wall. Also described are methods of manufacturing a flexible wall for a lens.

Abstract: Optical lens attachments and cameras are disclosed. The attachment comprises a coupling mechanism for mating engagement with at least one of a camera and an optical lens. A barrel is coupled at one end to the coupling mechanism. A negative lens unit is coupled to the other end of elongated barrel. A diopter lens is disposed between the barrel and the coupling mechanism. The coupling mechanism, the diopter lens, and the barrel are aligned with an optical axis. Also disclosed is a double swivel optical system, comprising a negative lens unit, a mirror oriented at an angle to the optical axis of the negative lens unit, a roof prism for rotating incident light rays by 90 degrees and inverting an image, a rotation mechanism permitting rotation of the negative lens unit about a vertical axis, an image rotator comprising a prism that can invert an image, the prism disposed within the image rotator, and another rotation mechanism permitting rotation of the roof prism about an optical axis of the image rotator.

Abstract: A packing assembly for location within a groove in one of a pair of relatively movable members comprises a deformable seal member having sealing lips engaging with the base wall of the groove and the surface of the other member, and a pair of support members. One or both side faces of each support member are provided with leakage grooves to enable fluid under pressure which collects in the zone defined between the support members, to be dissipated.