Abstract: A lens component comprising a first plastic lens element having a thin glass coating and a second lens element cemented to the glass coated surface of the first plastic element.

Abstract: A zoom lens comprises a plurality of lens elements arranged in at least two zooming lens units. The zoom lens is characterized in that at least one of the zooming lens units moves in a first direction, then reverses the direction of the movement to move in a second direction and then reverses the direction again to move in the first direction.

Abstract: A lens system has nominal focal length and aberrations and includes a plurality of lens components defined by design parameter values and a special airspace distance. The lens system is characterized in design such that manufacturing deviations from the design parameter values cause a variation from the nominal focal length and a variation in at least one of the aberrations. Both of these deviations can be offset simultaneously by a single change in the special airspace distance.

Abstract: A lens system particularly suitable for use in a camera using small format film has two lens units, a front negative power lens unit and a rear positive power lens unit. The rear lens unit has no negative lens elements and includes an aspheric surface and a diffractive surface.

Abstract: A cluster lens for imaging a transparency onto an image plane comprises a plurality of lenses which simultaneously have a field of view sufficient to include the transparency. All of the lenses image simultaneously. At least two of these lenses have different magnifications. The lenses are located in a spaced relationship to each other so that that not one of these lenses encroaches upon that section of the field of view of another lens that is used to image the transparency onto the image plane.

Abstract: In order to reduce complexity and cost of fabrication of zoom lenses, the real image forming lens group module at the front of the zoom lens is replaced with a two-element group where one of the elements has a diffractive lens on a curved surface thereof instead of the usually cemented doublet of the front group, but with substantially the same aberrations as a front group with three elements, including a cemented doublet. Aberrations (chromatic and monochromatic) produced by the first and second groups remain corrected by the combination of these groups over the zoom range of the lens. A second group housing two-elements, one of which has a curved surface on which a diffractive lens is provided, may be also be used to replace the three-element second lens group and particularly the cemented doublet thereof.

Abstract: An optical magnifier, preferably having only two elements and including a rear negative surface associated with an object to be viewed, which is aspheric. The aspheric surface follows a formula having a sag which is positive to help effect correction for field curvature, astigmatism and distortion. Preferably the lens has at least one other aspheric surface and a diffractive surface. The diffractive surface is preferably on a curved surface to assist in improving the quality of the magnifier with a limited number of elements.

Abstract: A reverse Galilean finder in which a front frame, preferably associated with a front element is projected away from the eye by the finder optics without separate frame projection optics to a position such that the distance between the apparent position of the frame to the eye and the rear vertex of the finder divided by the length of the finder is at least 2.2.

Abstract: A compact lens system has a predetermined focal length and comprises a plurality of lens elements and an internal aperture stop. The lens system is asymmetrical about the aperture stop. The plurality of lens elements define a field of view of at least 10 degrees. The plurality of lens elements include a front lens element, a rear lens element and at least one lens element located between the rear and the front lens elements. The rear lens element defines a rear vertex and a rear surface clear aperture with a predetermined diameter. The front lens element defines a front vertex and a front surface clear aperture with a predetermined diameter. The front and rear vertices are spaced apart less than 20% of the lens system's focal length. The front surface clear aperture diameter is within 10% of the rear surface clear aperture diameter.

Abstract: A zoom lens having two units of lens components including from the object side a positive optical unit and a negative optical unit. The zoom lens satisfies the following relationship ##EQU1## where eW is the principal point separation of the zoom lens when said zoom lens operates at a wide angle position and eT is the principal point separation of the zoom lens when said zoom lens operates at the telephoto position.

Abstract: A zoom lens having two units of lens components including from the object side a positive optical unit and a negative optical unit. The positive optical unit includes two lens components, a weak power lens component, and a second positive power lens component, while the negative optical unit provides most of the magnification change during zooming. The zoom lens has reduced aspheric decenter sensitivity.

Abstract: A compact objective lens with a diaphragm arranged behind the lens system suitable for use in very compact photographic cameras. The objective lens comprises a plurality of components arranged in a triplet or a triplet type configuration and is capable of covering at least a 55 degree field of view.

Abstract: A compact objective lens system with a diaphragm arranged in front of or preferably behind the lens system and suitable for use in compact photographic cameras. The objective lens comprises a plurality of components arranged in a triplet-type configuration that are capable of covering at least a 55 degree field of view and utilizes the locations of aperture stop, the lens bendings, and the size of lens elements, clear apertures of the lens element surfaces to enhance the lens system performance and to eliminate stray light problems.

Abstract: A lens system 10 suitable for use in imaging on film F in panoramic cameras 100. The lens system 10 comprising an aperture stop ST, a front lens unit 20 located behind the aperture stop ST, the front lens unit 20 including a triplet; and a rear lens unit 30, preferably a meniscus lens element 32, located behind the front lens unit 20. The triplet consists of two negative power lens elements 22, 26 and a positive power lens element 24 located between the negative power lens elements 22, 26.

Abstract: A real image zoom finder has a zoom portion with one or more moving elements to vary the magnification of the finder. A field lens is substantially separated from suitable erecting optics to defocus any scratches or dust on the zoom lens and also to increase the compactness of the system.

Abstract: An automatic printer for making prints of normal and panoramic format negative filmstrip image frames arbitrarily interspersed in a single filmstrip. Normal and panoramic projection systems are provided for projecting normal and panoramic images onto respective projection planes of the photographic print paper. Normal and panoramic format image frames are distinguished, and the appropriate projection system is employed through the insertion or withdrawal of a first reflective mirror into the projection path of the image bearing light beam. Zoom lens systems in each projection system are set to the appropriate magnifications for the width of print paper employed. The panoramic projection system employs a precision variable conjugate controlled zoom lens in association with a second movable mirror to adjust object plane to image plane distance to avoid overlap of the normal and panoramic projection planes at each magnification for each paper width.

Abstract: A zoom camera lens for an inexpensive camera, for example, a single use camera, has two plastic elements including a positive element and a negative element and a stop. Each of the surfaces of each of the elements is concave to the stop. Preferably, the lens has a curved image plane.

Abstract: A slide projector for both front and rear projection includes a shallow lens tunnel for mounting a simple wide-angle lens. In a first aspect, a second lens port is added to a conventional slide projector designed for front projection. A mirror pivots to invert and direct light rays from an illuminated slide to the simple wide-angle lens. In a second aspect, only the shallow lens tunnel is present and a rotating slide gate orients the slide, depending on operation in front or rear projection mode. Front projection in the second aspect requires a lens tunnel extension.

Abstract: A compact 2X zoom lens system consisting of a small number of lens elements. The zoom lens system consists of two lens groups, a first lens unit having a negative refractive power and a rear lens unit of positive refractive power. Both lens units are movable on an optical axis for zooming.

Abstract: A zoom lens having two units of lens components including from the object side a positive optical unit and a negative optical unit. The positive optical unit includes two lens subunits, a weak power subunit, and a positive power subunit, while the negative optical unit consists of a negative lens component and provides most of the magnification change during zooming.