Compact high performance zoom lens system

• US 7,123,421 B1
• Filed: 04/22/2005
• Issued: 10/17/2006
• Est. Priority Date: 04/22/2005
• Status: Active Grant

• Current Assignee: Panavision International LP (Panavision Incorporated)
• Original Assignee: Panavision International LP (Panavision Incorporated)
• Inventors: Moskovich, Jacob, Neil, Iain A., Yamanashi, Takanori
• Primary Examiner(s): Sugarman, Scott J.
• Assistant Examiner(s): Collins, Darryl J.
• Application Number:
  US11/112,098
• Publication Number:
  US 20060238887A1
• Time in Patent Office: 543 Days
• Field of Search: 359/685, 359/686, 359/689, 359/695, 359/683, 359/676, 359/691, 359/692
• US Class Current: 359/683
• CPC Class Codes: G02B 13/18 with lenses having one or more non-spherical faces, e.g. for reducing geometrical aberration G02B13/002 takes precedence

Abstract

A compact high performance objective zoom lens system is disclosed that provides optimum optical performance over the entire zoom focal length range at focus distances from close to infinity. The system comprises, from object space to image space, one focusing objective lens group (comprising a focus lens group and a stationary lens group) and three zoom lens groups aligned on the optical axis. The focus lens group and the zoom lens groups are axially movable along the optical axis for focusing and zooming. In one embodiment, the system has a focal length zoom region from about 19 mm to 90 mm, an aperture of F/2.7 and substantially the same optical performance as high quality fixed objective lenses of the same range. The performance characteristics of this system makes it suitable for use with both film and electronic detector cameras.

Claims

1. A high performance zoom lens system comprised of a single focusing objective lens group and multiple zoom lens groups aligned in that order on a common optical axis and arranged to collect radiation emanating from an object space and deliver said radiation to an axially stationary image space as a real image, said single focusing objective lens group comprising a focus lens group of negative optical power and a stationary lens group of positive optical power, said multiple zoom lens groups comprising a first zoom lens group of negative optical power, a second zoom lens group of positive optical power and a third zoom lens group of positive optical power and containing an optical stop of said zoom lens system, each of said focus lens group and said first, second and third zoom lens groups being axially movable, and said stationary lens group being axially stationary.

2. The high performance zoom lens system recited in claim 1, wherein said focus lens group and said stationary lens group have a combined positive optical power.

3. The high performance zoom lens system of claim 1, wherein said first, second and third zoom lens groups are axially movable in a monotonic manner over a full range of focal lengths between a minimum focal length and a maximum focal length of the zoom lens system.

4. The high performance zoom lens system of claim 1, wherein said focus lens group includes a non-spherical, non-plano, optically refractive surface.

5. The high performance zoom lens system of claim 4, wherein said third zoom lens group includes a non-spherical, non-plano, optically refractive surface.

6. The high performance zoom lens system of claim 5, wherein said zoom lens system has all remaining optically refractive surfaces that are substantially at least one of either spherical or plano.

7. The high performance zoom lens system of claim 1, wherein said third zoom lens group includes an adjustable iris.

8. The high performance zoom lens system of claim 1, wherein said focus lens group and said stationary lens group include lens elements for minimizing changes in a size of objects appearing in the real image during changes in focus distance from close to distant objects by axial movement of said focus lens group.

9. The high performance zoom lens system of claim 1, wherein said focus lens group is comprised of at least three optically refractive lens elements and includes at least one aspherical lens surface.

10. The high performance zoom lens system of claim 1, wherein said stationary lens group is comprised of at least four optically refractive lens elements.

11. The high performance zoom lens system of claim 1, wherein said first zoom lens group is comprised of at least four optically refractive lens elements of which one pair of doublet lens elements are included.

12. The high performance zoom lens system of claim 1, wherein said second zoom lens group is comprised of at least one optically refractive lens element.

13. The high performance zoom lens system of claim 1, wherein said third zoom lens group is comprised of at least eight optically refractive lens elements and includes at least one aspherical lens surface.

14. The high performance zoom lens system of claim 1, wherein the zoom lens system includes a lens element having an aspherical lens surface with a profile governed by the following equation and coefficients:

15. The high performance zoom lens system of claim 14, wherein said aspherical lens surface is included in said focus lens group.

16. The high performance zoom lens system of claim 1, wherein the zoom lens system includes a lens element having an aspherical lens surface with a profile governed by the following equation and coefficients:

17. The high performance zoom lens system of claim 16, wherein said aspherical lens surface is included in said third zoom lens group.

18. A high performance zoom lens system comprised of a single focusing objective lens group and multiple zoom lens groups aligned in that order on a common optical axis, said single focusing objective lens group having a focus lens group of negative optical power and a stationary lens group of positive optical power, said focus lens group being separately axially moveable along the optical axis and said stationary lens group being axially stationary, said multiple zoom lens groups comprising a first zoom lens group, a second zoom lens group and a third zoom lens group, said first zoom lens group being axially movable in a non-monotonic manner over a full range between minimum and maximum focal lengths, said second zoom lens group being axially movable in a monotonic manner over the full range between minimum and maximum focal lengths, and said third zoom lens group having an optical stop and being axially movable in a monotonic manner over the full range between minimum and maximum focal lengths.

19. The high performance zoom lens system of claim 18, wherein said focus lens group and said stationary lens group have a combined positive optical power.

20. The high performance zoom lens system of claim 18, wherein said focus lens group includes a non-spherical, non-plano, optically refractive surface.

21. The high performance zoom lens system of claim 18, wherein said third zoom lens group includes a non-spherical, non-plano, optically refractive surface.

22. The high performance zoom lens system of claim 18, wherein said third zoom lens group includes an adjustable iris.

23. The high performance zoom lens system of claim 18, wherein said focus lens group and said stationary lens group include lens elements for minimizing changes in a size of objects appearing in the real image during changes in focus distance from close to distant objects by axial movement of said focus lens group.

24. A high performance zoom lens system comprised of a single focusing objective lens group and multiple zoom lens groups aligned in that order on a common optical axis and arranged to collect radiation emanating from an object space and deliver said radiation to an axially stationary image space as a real image, said single focusing objective lens group comprising a focus lens group and a stationary lens group, said focus lens group of negative optical power and being axially movable with at least one non-spherical, non-plano, optically refractive surface, said stationary lens group of positive optical power and being axially stationary, said multiple zoom lens groups comprising first, second and third zoom lens groups, said first zoom lens group of negative optical power and being axially movable, said second zoom lens group of positive optical power and being axially movable, and said third zoom lens group being of positive optical power and axially movable with at least one non-spherical, non-plano optically refractive surface and an adjustable optical stop, said zoom lens system having remaining optically refractive surfaces that are substantially at least one of either spherical or plano, and said zoom lens system via axial positioning of said focus lens group and said multiple zoom lens groups providing a high level of optical performance through focusing and zooming ranges at the real image.

25. The high performance zoom lens system of claim 24, wherein each said non-spherical, non-plano optically refractive surface is an aspherical lens surface.

26. The high performance zoom lens system of claim 24, wherein said single objective focusing lens group has a combined positive optical power.

27. A high performance zoom lens system comprised of glass lens elements (1) through (20) aligned in that order on a common optical axis and arranged to collect radiation emanating from an object space and deliver said radiation to an axially stationary image space as a real image;

said lens elements forming a single objective focusing lens group (51) comprising a focus lens group (52), and a stationary lens group (53), a zoom lens group (54) comprising a first zoom lens group (55), a second zoom lens group (56), and third zoom lens group (57), said focus lens group and said first, second and third zoom lens groups each being axially movable;

said focus lens group comprising lens elements (1), (2) and (3), said stationary lens group comprising lens elements (4), (5), (6) and (7), said first zoom lens group comprising lens elements (8) through (11), said second zoom lens group comprising lens element (12), and said third zoom lens group having an optical stop and comprising lens elements (13) through (20); and

wherein lens element surfaces, dummy surfaces, an iris at an optical stop, an object plane and an image plane are identified as (O) and (S1) through (S41), said lens element surfaces (S3) and (S26) are aspheric, and said lens elements, lens element surfaces, dummy surfaces, iris at the optical stop, object plane and image plane have the following order, relationships and characteristics;

28. The high performance zoom lens system of claim 27, wherein the maximum aperture diameters (mm) at each surface (S1) through (S41), excluding said dummy surfaces, are as follows;

93.00 at (S2), 78.92 at (S3), 78.87 at (S4), 79.21 at (S5), 79.86 at (S6), 79.10 at (S7), 67.85 at (S8), 66.64 at (S9), 58.43 at (S10), 53.56 at (S11), 52.37 at (S12), 50.66 at (S13), 49.49 at (S14), 38.09 at (S15), 32.00 at (S16), 31.76 at (S17), 29.00 at (S18), 28.32 at (S19), 27.96 at (S20), 27.36 at (S21), 28.68 at (S22), 28.65 at (S23), 28.78 at (S24), 29.40 at (S25), 29.26 at (S26), 29.26 at (S27), 31.11 at (S28), 32.60 at (S29), 33.08 at (S30), 32.71 at (S31), 32.14 at (S32), 29.68 at (S33), 28.96 at (S34), 26.42 at (S35), 28.89 at (S36), 29.20 at (S37), 30.77 at (S38), 30.75 at (S39), and 27.80 at (S41).

29. The high performance zoom lens system of claim 27, wherein said aspheric lens surface S3 has a profile governed by the following equation and coefficients:

30. The high performance zoom lens system of claim 27, wherein said aspheric lens surface S26 has a profile governed by the following equation and coefficients: