Abstract: An ultrasonic camera having a high efficiency ultrasonic lens is coupled to a ultrasonic transmitter/receiver by a stretched membrane interface. The ultrasonic lens provides highly efficient transmission of ultrasound without introducing aberrations. The ultrasound system also uses a quasi incoherent source to reduce speckle noise in the image.

Abstract: An ultrasonic camera having a high efficiency ultrasonic lens is coupled to a ultrasonic transmitter/receiver by a stretched membrane interface. The ultrasonic lens provides highly efficient transmission of ultrasound without introducing aberrations. The ultrasound system also uses a quasi incoherent source to reduce speckle noise in the image.

Abstract: There is provided an improved night vision goggle having a housing containing an objective lens assembly, an image intensifier tube, a collimator assembly, a splitter member, and a pair of afocal telescopes. The optical axis of the afocal telescopes are offset from the optical axis of the collimator and objective lens assemblies. A pair of achromatic doublet lens assemblies are mounted side-by-side on the exit side of the collimator and near the entrance pupils of the telescopes. The optical axes of the doublet lens assemblies are coaxial with the optical axes of the telescopes. The achromatic doublet lens assemblies thus collect light from a sub-diameter, decentered aperture of the collimator assembly, and correct axial chromatic aberration in the telescopes.

Abstract: There is provided an improved night vision goggle having a housing containing an objective lens assembly, an image intensifier tube, a collimator assembly, a splitter member, and a pair of afocal telescopes. The optical axis of the afocal telescopes are offset from the optical axis of the collimator and objective lens assemblies. A pair of achromatic doublet lens assemblies are mounted side-by-side on the exit side of the collimator and near the entrance pupils of the telescopes. The optical axes of the doublet lens assemblies are coaxial with the optical axes of the telescopes. The achromatic doublet lens assemblies thus collect light from a sub-diameter, decentered aperture of the collimator assembly, and correct axial chromatic aberration in the telescopes.

Abstract: A zone focusing lens system is provided for use as a photographic camera objective. In the system, a fixed positive meniscus is placed ahead of the system aperture stop and is provided with an aspheric surface that is structured primarily to correct for off-axis aberrations. A lens disk having a plurality of different meniscus lens elements is located so that each of its elements can be selectively rotated into alignment proximate the system aperture stop to provide system focal lengths appropriate for sharply focusing objects located within different distance ranges. Each of the lens disk elements is provided with an aspheric surface that is structured primarily to reduce spherical aberrations.

Abstract: A method and optical apparatus by which a camera initially adapted to utilize a zooming optical system of the type which includes a variable focus, afocal zoom lens section and a prime lens section is adapted to utilize only the prime lens section of the zooming optical system.

Abstract: A multi-element photographic lens has a strongly aspheric surface formed on a strong lens element that is movable relative to the other elements along a common optical axis. The aspheric surface corrects at least the lower order aberrations contributed by the movable element thereby allowing the movement to focus the lens over a wide focus scale or object distance. Preferably, the elements are formed of plastic, the movable element is a front element, and at least one other aspheric surface is formed on a lens element.