Eastman-kodak Company

U.S. Precision Lens Incorporated

Benopcon, Inc.

Vivitar Corporation

Panavision Inc.

Polaroid Corporation

The Stanley Works

Lenzar Optics Corporation

Fjw Industries, Inc.

Opcon Associates, Inc.

Ellis I Betensky

Melvyn H Kreitzer

Jacob Moskovich

Paul L Ruben

Iain A Neil

William J Hildebrandt

James Brian Caldwell

Takanori Yamanashi

A zoom lens system is disclosed. The zoom lens system forms a final image of an object and a first intermediate real image between the object and the final image. The zoom lens system includes a first optical unit located between the object and the first intermediate real image. The first optical unit comprises at least one optical subunit which is moved to change the size (magnification) of the first intermediate real image. The zoom lens system also includes a second optical unit located between the first intermediate real image and the final image, at least a portion of which is moved to change the size (magnification) of the final image. The zoom lens system provides a wide zoom range of focal lengths with continuous zooming between the focal lengths and optional image stabilization.

Zoom lens system

A high performance zoom lens system formed by multiple focus lens groups, multiple zoom lens groups and single auxiliary lens group aligned in that order on a common optical axis and arranged to collect radiation emanating from an object space and deliver that radiation to an axially stationary real image in an image space, such as on a film plane or video CCD. The multiple focus lens groups comprise a first focus lens group of negative optical power that is axially movable and contains at least one non-spherical, non-plano, optically refractive surface, and a second focus lens group of positive optical power that is axially movable. The multiple zoom lens groups comprise a first zoom lens group of negative optical power that is axially movable, and a second zoom lens group of positive optical power that is axially movable and contains an optical stop or iris. The single auxiliary lens group is of relatively weak positive optical power compared to the other lens groups, is axially stationary and contains at least one non-spherical, non-plano optically refractive surface. The remaining optically refractive surfaces of said zoom lens system being substantially spherical or plano. By axial positioning of said multiple focus lens groups and said multiple zoom lens groups, the zoom lens system provides a high level of optical performance at said real image through its entire and substantial focusing and zooming ranges.

High performance zoom lens system

Variable power lens systems for use with electronic imaging systems, e.g., systems employing CCDs, are provided. The systems take advantage of the fact that the images detected by electronic imaging systems are small, e.g., the image diagonal can be 5.5 millimeters or less. The lens systems employ thick lens elements, whose diameters and thicknesses are large relative to the image size, and large air spaces between lens elements. The systems also employ weak lens units. In this way, simplified lens designs having excellent optical properties at less cost are provided. In certain embodiments, the lens systems contain only three lens elements, e.g., a negative first lens element, a positive second lens element for zooming, and a positive third lens element, with the first and/or the third lens element serving as a compensator.

Variable power lens systems for producing small images

A method for producing a lens system is provided in which an exact field curvature (EFC) value is determined for at least one principal ray, the EFC value being given by:

Method for correcting field curvature

Binoculars designed to provide a large aided static field of view are provided. The binoculars are characterized by S/D ratios of above 2.8, where S is the binoculars' aided static field of view calculated by multiplying the binoculars' magnifying power by the binoculars' semi field of view in object space and D is given by tan.sup.-1 [(R.sub.ex +1.5)/13], where R.sub.ex is the radius of the binoculars exit pupil the following expression in which R.sub.ex and the constants 1.5 and 13 are in milliliters. As a result of the increased S/D ratio, the binoculars of the invention minimize the sensation of tunnel vision which normally occurs when binoculars are used and reduce the user's apprehension of missing activities in his or her peripheral vision. In certain embodiments, a movable field lens unit is employed to provide variable power and a negative corrector lens unit is employed for aberration correction and to minimize the size of the binoculars. The binoculars are suitable for mass production and general consumer use.

Wide angle binocular system with variable power capability

Binoculars designed to provide a large aided static field of view are provided. The binoculars are characterized by S/D ratios of above 2.8, where S is the binoculars' aided static field of view calculated by multiplying the binoculars' magnifying power by the binoculars' semi field of view in object space and D is given by tan.sup.-1 [(R.sub.ex +1.5)/13], where R.sub.ex is the radius of the binoculars' exit pupil and where R.sub.ex and the constants 1.5 and 13 are measured in millimeters. As a result of the increased S/D ratio, the binoculars' of the invention minimize the sensation of tunnel vision which normally occurs when binoculars are used and reduce the user's apprehension of missing activities in his or her peripheral vision. In certain embodiments, a movable field lens unit is employed to provide variable power and a negative corrector lens unit is employed for aberration correction and to minimize the size of the binoculars. The binoculars are suitable for mass production and general consumer use.

Binoculars designed to provide a large aided static field of view are provided. The binoculars are characterized by S/D ratios of above 2.8, where S is the binocular' aided static field of view calculated by multiplying the binoculars' magnifying power by the binoculars' semi field of view in object space and D is given by tan.sup.-1 [(R.sub.ex +1.5)/13], where R.sub.ex is the radius of the binoculars exit pupil and where R.sub.ex and the constants 1.5 and 13 are measured in millimeters. As a result of the increased S/D ratio, the binoculars' of the invention minimize the sensation of tunnel vision which normally occurs when binoculars are used and reduce the user's apprehension of missing activities in his or her peripheral vision. In certain embodiments, a movable field lens unit is employed to provide variable power and a negative corrector lens unit is employed for aberration correction and to minimize the size of the binoculars. The binoculars are suitable for mass production and general consumer use.

Binoculars designed to provide a large aided static field of view are provided. The binoculars are characterized by S/D ratios of above 2.8, where S is the binoculars' aided static field of view calculated by multiplying the binoculars' magnifying power by the binoculars' semi field of view in object space and D is given by tan.sup.-1 [(R.sub.ex +1.5)/13], where R.sub.ex is the radius of the binoculars' exit pupil and where R.sub.ex and the constants 1.5 and 13 are measured in millimeters. As a result of the increased S/D ratio, the binoculars of the invention minimize the sensation of tunnel vision which normally occurs when binoculars are used and reduce the user's apprehension of missing activities in his or her peripheral vision. In certain embodiments, a movable field lens unit is employed to provide variable power and a negative corrector lens unit is employed for aberration correction and to minimize the size of the binoculars. The binoculars are suitable for mass production and general consumer use.

A zoom lens having two groups of lens components including from the object side a positive group and a negative group. The positive group includes two lens units, a weak unit, and a positive unit, while the negative group has at least one negative lens component and provides most of the magnification change during zooming.

Zoom lens having weak front lens group

Zoom lens systems for use with moderately large image formats, such as those found in instant photography cameras, are provided. The systems include three lens units arranged in a negative/positive/negative power sequence and have a fixed aperture stop associated with the unit nearest the image. The positive unit is used for zooming and either the first or the third negative unit is used for compensating and focusing. Alternatively, the negative unit nearest the image is used for compensating and the negative unit farthest from the image is used for focusing. The systems achieve a long back focal length, a short front vertex to image distance, and in their simplest embodiments can consist of just three lens elements.

Zoom lens systems

A zoom lens suitable for an inexpensive camera has a front positive lens group and a rear negative lens group. Both groups move for zooming with the rear negative group providing most of the variation in focal length. The front positive group includes a front negative component and a rear positive component while the rear negative group includes a rear negative component and a weak plastic element having at least one aspheric surface. The plastic element is sufficiently weak that it does not cause variation in focus with normal variations in temperature and relative humidity. All other elements in the zoom lens are glass.

Zoom lens having weak plastic element

Zoom projection lens systems are provided which have 1) an entrance pupil which remains at a substantially fixed position as zooming takes place, and 2) a operative aperture stop, distinct from the system's physical aperture stop, which moves through lens surfaces as zooming takes place. The fixed entrance pupil allows for efficient coupling to a light source throughout the magnification range of the system. Methods which can be used to design and produce zoom lens systems of this type and which employ a pseudo-aperture stop are also disclosed.

Zoom projection lens systems

A real image zooming viewfinder comprising three optical units with refracting optical power and an additional moving reflective optical unit. Zooming is accomplished by moving one of the refractive optical units and the additional reflective optical unit or by moving the first and the second optical units. The need for field lens is eliminated by having the first and the second unit cooperate to make the finder system telecentric with respect to principal rays at the intermediate image plane.

Growing community of inventors

Redding, CT, United States of America

Ellis I Betensky