Patents by Inventor J. Brian Caldwell

J. Brian Caldwell has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10126533
    Abstract: An anamorphic objective having a relatively small anamorphic factor but with relatively pronounced residual anamorphic artifacts is formed by reducing the anamorphic factor with anamorphic lens elements located on the image side of the aperture stop. The lens section on the object side of the aperture stop must therefore have a relatively large anamorphic factor, and this creates the desired residual anamorphic artifacts. The disclosed anamorphic objective is suited either to an integrated optical design or to a modular approach in which the anamorphic factor reduction optics are connected as a removable attachment to an independently well-corrected anamorphic optical system. The anamorphic objective has a relatively small anamorphic squeeze ratio while simultaneously producing relatively large residual anamorphic characteristics.
    Type: Grant
    Filed: July 28, 2017
    Date of Patent: November 13, 2018
    Inventor: J. Brian Caldwell
  • Patent number: 8903232
    Abstract: An optical attachment having five or six elements and configured to be operably arranged on the image side of an objective lens to reduce the focal length and focal ratio of the objective lens is disclosed. The optical attachment is particularly suitable for adapting objective lenses designed with a relatively large working distance for a large format size to cameras having a smaller format size and relatively small permissible working distance. The optical attachments disclosed herein have high image quality at large aperture over a large field of view, and can be well-corrected for all major aberrations.
    Type: Grant
    Filed: July 12, 2014
    Date of Patent: December 2, 2014
    Assignee: Caldwell Photographic, Inc.
    Inventor: J. Brian Caldwell
  • Patent number: 8879901
    Abstract: An optical attachment configured to be operably attached to the image side of an objective lens to reduce the focal length and focal ratio of the objective lens. The focal-reducing attachment includes four lens elements and has a magnification of between 0.5 and 1. The focal-reducing lens can work with objective lenses having relatively large working distances for a large format size as well as with cameras having a smaller format size and relatively small permissible working distance.
    Type: Grant
    Filed: August 20, 2012
    Date of Patent: November 4, 2014
    Assignee: Caldwell Photographic, Inc.
    Inventors: J. Brian Caldwell, Wilfried Bittner
  • Publication number: 20140085532
    Abstract: A corrective optical system for an imaging optical system is disclosed, wherein the imaging optical system has an objective having a working space, and whose imaging performance is not corrected for one or more plane parallel plates located in the working space. The corrector optical system resides in the working space between the one or more plane parallel plates and objective and serves to reduce the aberrations introduced by the one or more plane parallel plates. The corrector optical system enables objectives originally designed for film to be used with digital cameras.
    Type: Application
    Filed: September 11, 2013
    Publication date: March 27, 2014
    Applicant: Caldwell Photographic, Inc.
    Inventor: J. Brian Caldwell
  • Patent number: 8678676
    Abstract: A tilt shift lens adapter having an adapter body with first and second body portions configured to provide precision tilting and shifting functions is disclosed. Opposite sides of the adapter body are configured to respectively engage a camera and a lens. Tilting and shifting are precisely controlled using precision tilting and shifting mechanisms. The tilting mechanism includes a neutral setting for ensuring precise parallelism between the lens and camera flanges when required. The adapter includes a mount to provide good balance and holding strength when heavy lenses are attached. An optional aperture adjustment mechanism manually adjusts lenses having no aperture ring.
    Type: Grant
    Filed: September 19, 2011
    Date of Patent: March 25, 2014
    Inventors: Erwin Scholz, Wilfried Aloie Anton Bittner, J. Brian Caldwell
  • Publication number: 20130064532
    Abstract: An optical attachment configured to be operably attached to the image side of an objective lens to reduce the focal length and focal ratio of the objective lens. The focal-reducing attachment includes four lens elements and has a magnification of between 0.5 and 1. The focal-reducing lens can work with objective lenses having relatively large working distances for a large format size as well as with cameras having a smaller format size and relatively small permissible working distance.
    Type: Application
    Filed: August 20, 2012
    Publication date: March 14, 2013
    Inventors: J. Brian Caldwell, Wilfried Bittner
  • Patent number: 8169717
    Abstract: Large aperture optical systems that are extremely well corrected over a large flat field and over a large spectral range are disclosed. Breathing and aberration variation during focusing are optionally controlled by moving at least two groups of lens elements independently. Aberration correction in general is aided by allowing the working distance to become short relative to the format diagonal. Field curvature is largely corrected by a steeply curved concave surface relatively close to the image plane. This allows the main collective elements to be made of low-index anomalous dispersion materials in order to correct secondary spectrum. In wide-angle example embodiments, distortion may be controlled with an aspheric surface near the front of the lens.
    Type: Grant
    Filed: June 7, 2010
    Date of Patent: May 1, 2012
    Assignee: Caldwell Photographic, Inc.
    Inventor: J. Brian Caldwell
  • Publication number: 20120070141
    Abstract: A tilt shift lens adapter having an adapter body with first and second body portions configured to provide precision tilting and shifting functions is disclosed. Opposite sides of the adapter body are configured to respectively engage a camera and a lens. Tilting and shifting are precisely controlled using precision tilting and shifting mechanisms. The tilting mechanism includes a neutral setting for ensuring precise parallelism between the lens and camera flanges when required. The adapter includes a mount to provide good balance and holding strength when heavy lenses are attached. An optional aperture adjustment mechanism manually adjusts lenses having no aperture ring.
    Type: Application
    Filed: September 19, 2011
    Publication date: March 22, 2012
    Inventors: Erwin Scholz, Wilfried Aloie Anton Bittner, J. Brian Caldwell
  • Patent number: 7808718
    Abstract: An afocal Galilean attachment lens is disclosed, with the lens comprising, along an optical axis, a first lens group with overall negative optical power and a second lens group with overall positive power. The first and second lens groups are arranged to define a Galilean configuration. The lens also has exit and an entrance pupils with respective diameters DEX and DEN that define a pupil magnification PM=DEX/DEN>4 and in some embodiments PM>10. The afocal Galilean attachment lens also has a length parameter defined LP>200 and in some embodiments LP>700. The extreme length of the afocal Galilean attachment allows for photographing or filming objects that are remote or otherwise hard to photograph while also providing a relatively large depth of field.
    Type: Grant
    Filed: April 27, 2009
    Date of Patent: October 5, 2010
    Assignee: FM-Assets Pty Ltd
    Inventors: James A. Frazier, J. Brian Caldwell
  • Publication number: 20100246031
    Abstract: Large aperture optical systems that are extremely well corrected over a large flat field and over a large spectral range are disclosed. Breathing and aberration variation during focusing are optionally controlled by moving at least two groups of lens elements independently. Aberration correction in general is aided by allowing the working distance to become short relative to the format diagonal. Field curvature is largely corrected by a steeply curved concave surface relatively close to the image plane. This allows the main collective elements to be made of low-index anomalous dispersion materials in order to correct secondary spectrum. In wide-angle example embodiments, distortion may be controlled with an aspheric surface near the front of the lens.
    Type: Application
    Filed: June 7, 2010
    Publication date: September 30, 2010
    Inventor: J. Brian Caldwell
  • Patent number: 7733581
    Abstract: Large aperture optical systems that are extremely well corrected over a large flat field and over a large spectral range are disclosed. Breathing and aberration variation during focusing are optionally controlled by moving at least two groups of lens elements independently. Aberration correction in general is aided by allowing the working distance to become short relative to the format diagonal. Field curvature is largely corrected by a steeply curved concave surface relatively close to the image plane. This allows the main collective elements to be made of low-index anomalous dispersion materials in order to correct secondary spectrum. In wide-angle example embodiments, distortion may be controlled with an aspheric surface near the front of the lens.
    Type: Grant
    Filed: August 19, 2008
    Date of Patent: June 8, 2010
    Inventor: J. Brian Caldwell
  • Publication number: 20090237810
    Abstract: An afocal Galilean attachment lens is disclosed, with the lens comprising, along an optical axis, a first lens group with overall negative optical power and a second lens group with overall positive power. The first and second lens groups are arranged to define a Galilean configuration. The lens also has exit and an entrance pupils with respective diameters DEX and DEN that define a pupil magnification PM=DEX/DEN>4 and in some embodiments PM>10. The afocal Galilean attachment lens also has a length parameter defined LP>200 and in some embodiments LP>700. The extreme length of the afocal Galilean attachment allows for photographing or filming objects that are remote or otherwise hard to photograph while also providing a relatively large depth of field.
    Type: Application
    Filed: April 27, 2009
    Publication date: September 24, 2009
    Inventors: James A. Frazier, J. Brian Caldwell
  • Publication number: 20090052064
    Abstract: Large aperture optical systems that are extremely well corrected over a large flat field and over a large spectral range are disclosed. Breathing and aberration variation during focusing are optionally controlled by moving at least two groups of lens elements independently. Aberration correction in general is aided by allowing the working distance to become short relative to the format diagonal. Field curvature is largely corrected by a steeply curved concave surface relatively close to the image plane. This allows the main collective elements to be made of low-index anomalous dispersion materials in order to correct secondary spectrum. In wide-angle example embodiments, distortion may be controlled with an aspheric surface near the front of the lens.
    Type: Application
    Filed: August 19, 2008
    Publication date: February 26, 2009
    Inventor: J. Brian Caldwell
  • Patent number: 5206189
    Abstract: An improved method for the production of a monolithic multicomponent oxide glass is achieved by forming an oxide host gel by a sol-gel process, placing the host gel in an aqueous solution of a salt of at least one metal selected from the group consisting of Li, Na, K, Rb, Cs, Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Pb, precipitating the metal salt in the gel and sintering the gel containing the precipitated salt. The method can incorporate large amounts of metals into the glass which are otherwise difficult or impossible to incorporate into precursor gels by conventional methods.
    Type: Grant
    Filed: October 25, 1991
    Date of Patent: April 27, 1993
    Assignees: Instituto Guido Donegani S.p.A., Enichem S.p.A.
    Inventor: J. Brian Caldwell
  • Patent number: 5182236
    Abstract: A gradient index glass comprised of (SiO.sub.2).sub.m (R.sub.2 O).sub.n X.sub.p, wherein R is Li, Na, K, Rb, or Cs, and X=TiO.sub.2, ZrO.sub.2 and/or HfO.sub.2, m is 44 to 99, n is 0.25 to 20, p is at least 0.1, and m+n+p=100.
    Type: Grant
    Filed: September 24, 1991
    Date of Patent: January 26, 1993
    Assignees: Enichem S.p.A., Istituto Guido Donegani S.p.A.
    Inventors: J. Brian Caldwell, Mark A. Banash, Tessie M. Che, Robert M. Mininni, Victor N. Warden
  • Patent number: 4902650
    Abstract: A sol-gel method for making gradient-index glass and a novel composition therefor, comprising at least a ternary system of metal alkoxides.
    Type: Grant
    Filed: July 15, 1988
    Date of Patent: February 20, 1990
    Assignee: The University of Rochester
    Inventors: J. Brian Caldwell, Duncan T. Moore
  • Patent number: 4797376
    Abstract: A sol-gel method for making gradient-index glass and a novel composition therefor, comprising at least a ternary system of metal alkoxides.
    Type: Grant
    Filed: June 9, 1987
    Date of Patent: January 10, 1989
    Assignee: University of Rochester
    Inventors: J. Brian Caldwell, Duncan T. Moore