Abstract:
The described lens assembly for use with a camera having a camera body includes a tilt assembly portion configured to allow pivotal movement of the lens body relative to the camera body. The lens assembly further includes a focus assembly configured to axially adjust a position of a removable optic assembly mounted to the focus assembly relative to the lens body to control focus of the lens assembly when the optic assembly is installed in the lens body. The lens body and focus assembly may be structured to remain coupled to the camera body after the optic assembly is removed from the focus assembly.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a division of U.S. patent application Ser. No. 12/811,447, filed Oct. 7, 2010, now U.S. Pat. No. 8,400,724 B2 which was a national stage of International Patent Application PCTUS2008/088681 filed Dec. 21, 2008, which claimed benefit of U.S. Provisional Patent Application No. 61/099,104 filed Sep. 22, 2008, and of U.S. Provisional Patent Application No. 61/019,211 filed Jan. 4, 2008, all of which are incorporated herein in their entireties by reference thereto. 
    
    
     TECHNICAL FIELD 
     The present disclosure generally relates to movable lens assemblies associated with photography. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1A  is an isometric front view and  FIG. 1B  is a side view of a lens assembly configured in accordance with an embodiment of the disclosure. 
         FIG. 2A  is an isometric exploded front view,  FIG. 2B  is an isometric exploded rear view, and  FIG. 2C  is an exploded side view of a lens assembly configured in accordance with an embodiment of the disclosure. 
         FIG. 3  is a side view of an optical cup in accordance with an embodiment of the present invention. 
         FIG. 4  is a top end view of the optical cup of  FIG. 3   
         FIGS. 5A-C  are top, side, and bottom views of different optical cups with different colored retaining rings 
         FIG. 6  is a side view of the optical cup of  FIG. 3  adjacent to a carrying assembly. 
         FIG. 7  is a view of lens assemblies with optical cups installed therein in accordance with an embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     The following disclosure describes several embodiments of lens assemblies and associated methods. Certain details are set forth in the following description and in  FIGS. 1A-7  to provide a thorough understanding of various embodiments of the disclosure. Other details describing well-known structures and components often associated with lens assemblies, however, are not set forth below to avoid unnecessarily obscuring the description of the various embodiments of the disclosure. 
     Many of the details and features shown in the Figures are merely illustrative of particular embodiments of the disclosure. Accordingly, other embodiments can have other details and features without departing from the spirit and scope of the present disclosure. In addition, those of ordinary skill in the art will understand that further embodiments can be practiced without several of the details described below. Various embodiments of the disclosure can include structures other than those illustrated in the Figures and are expressly not limited to the structures shown in the Figures. 
       FIG. 1A  is a isometric front view and  FIG. 1B  is a side view of a lens assembly  100  configured in accordance with an embodiment of the disclosure. The lens assembly  100  generally includes a ball in socket based tilt lens (“BSBTL”) that provides a means by which photographers are able to easily create unique, selective focus imagery previously associated with cumbersome to use tilt/shift lenses and view cameras. The BSBTL is a focus and tilt lens system that allows lenses to be tilted off-parallel related to the image plane. The BSBTL replaces the cumbersome adjustments of a tilt/shift lens and view cameras with a natural, simple and intuitive system for moving a lens off parallel from the image plane. Several subassemblies and components of the lens assembly, including the BSBTL, are described below in more detail with reference to  FIGS. 2A-2C . 
       FIG. 2A  is an isometric exploded front view,  FIG. 2B  is an isometric exploded rear view, and  FIG. 2C  is an exploded side view of the lens assembly  100  configured in accordance with an embodiment of the disclosure. Referring to  FIGS. 2A-2C  together, the lens assembly  100  of the illustrated embodiment includes the following features in one embodiment: a camera mount  202  that locks onto an interchangeable lens camera, an adapter  212  with bayonet-type mounting system for an optical assembly  210 , an optical cup  214  removably retained in the adapter, a front to back focus assembly  220  holding the adapter  212  (and optical assembly  210 ), a ball in socket tilt assembly  240 , a tensioner assembly  250  to adjust the friction setting on the ball in socket tilt assembly  240 , and metal compression springs to hold the lens securely when ball is held in its least tensioned state. Several of these assemblies and their respective components are further described below, without limiting the structure and/or features of these components and assemblies. 
     The mount  202  can be a rigid and durable plate with a bayonet-type or screw feature allowing secure and precise attachment to the front of a camera body. The mount  202  can therefore provide a precise alignment of the assembly  100  when it is held, tilted, focused and or/zoomed. 
     The ball in socket tilt assembly  240  includes a ball  242  and a race  244 . In one embodiment, the race  244  can be made from a flexible material, such as a plastic. As such, the race  244  can be a flexible ring that surrounds the front portion of the ball  242  or captures the ball  242 , and limits the ball  242  from moving generally out of the ball&#39;s ideal rotational axis within the assembly  240 . The race  244  can be slipped over the ball  242  and is held in place by the clamp  256 . For example, the flexible race  244  can have an inner diameter that is less than an outer diameter of the ball  242  so that the race  244  is at least partially retained on the ball  242 . The ball  242  can be a partial sphere at the base of the assembly  240 . The ball  242  can provide a rigid connection between the camera mount  202  and the focusing assembly  250 . 
     The ball socket tilt assembly  240  allows a photographer the option of tilting the optical assembly  210  up to about 17 degrees (i.e., about 17 degrees in one direction, for a total of 34 degrees from one extreme to another) out of parallel with the image plane in any direction upon the axis of this ball  242  through manual manipulation of the front of the ball socket tilt assembly  240 . Tilting the optical assembly  210  thus changes the positioning in the image of the sweet spot of focus and/or changing angle of the plane of focus as seen in the camera&#39;s single lens reflex viewfinder. 
     According to one embodiment, the ball socket tilt assembly  240  can also include a tilt limiter, such as an accessory ring snapped to or fitted around the throat in front of the spherical feature of the ball  242 . The tilt limiter can be removable and limit the amount of tilt to something less than about 17 degrees in one direction for the purpose of keeping the lens inside of a range of tilt that the photographer desires. The tilt limiter can limit this movement by causing the clamp  256  and/or race  244  to contact the tilt limiter prior to tilting the lens to the point at which the full amount of tilt (e.g., about 17 degrees in one embodiment) would, without the limiter in place, be possible. In other embodiments, multiple tilt limiters may be used for different maximum tilt angle ranges. 
     The tensioner assembly  250  can include a knurl adapter  252 , a base  254 , a clamp  256 , a tensioner ring  258 , and a tensioner ring overmold  260 . The base  254  can be a ring of generally rigid, self lubricating material surrounding the rear of the ball  242 , to capture the ball  242  and tension the ball  242  forward into its ideal rotational axis. The tensioner ring  258  can be a plastic or rubber ring with internal threads which, when turned in one rotational/tilting direction by the user, engages its internal threads to the threads on the outside diameter of the base  254 , and in so doing, increases the forward tension on the ball  242  by moving the base  254  closer to the race  244 . The tensioner ring overmold  260  can be made of a plastic or rubber material that engages the tensioner ring  258 . When the tensioner ring  258  is turned in the opposite rotational direction by the user, the tensioner ring  258  disengages its internal threads from the threads on the outside diameter of the base  254 , and in so doing decreases the tension on the ball  242 . 
     The clamp  256  is positioned at the center of the tilt mechanism holding the mount  204 , race  244 , base  254 , springs, tensioner ring  258 , and tensioner ring overmold  260  in precise alignment with the ball  242  so as to allow the user to grip the outside edge of the tensioner ring overmold  260  and turn in one rotational direction to increase the amount of force needed to rotate/tilt the ball  242  between the race  244  and the base  254 , and likewise allow the user to grip the outside edge of the tensioner ring overmold  260  and turn in another direction to decrease the amount of force needed to rotate the ball  242  between the race and the base  254 . 
     In one embodiment, the clamp  256  includes engageable arms with rounded ball ends extending from the clamp  256  to engage a channel or groove on the outside diameter of the ball  242  for the purpose of providing the photographer with a quick indication of when the ball is centered (e.g., no tilt), placing the optics in a parallel condition with the image plane. These fingers can be at the end of arms which will push inward when the tensioner (e.g., tensioner ring  258  and/or tensioner ring overmold  260 ) is rotated past an indentation beyond and in the same direction as the tensioner&#39;s loosest ball capture position. These rounded ball ends can extend inward and press on the ball  242  while remaining somewhat flexible such that when the rounded ball ends are pushed inward but are not inside of the channel groove the system will continue to rotate freely until the fingers fall into the groove and create additional resistance to the ball  242  being moved back into a tilted position. 
     In certain embodiments, the assembly  100  can also include compression springs that push the rear of the base  254  forward in the assembly  100  to keep a minimum tension on the ball  242  between the race  244  and the base  254  and to allow for consistent tension despite potential asymmetric aspects of the ball  242  that would, apart from the spring tension, cause the ball  242  to have more or less tension depending upon the tilt of the ball  242  in what, without the springs, would be a rigid system. 
     The focus assembly  220  can include a rear focus ring  222 , a focus sleeve  224 , a slotted focus ring  226 , a collar  228 , and a front focus ring  230 . The rear focus ring can be adjacent to the ball  242  where it meets the back of the collar  228 , which serves as a precision bearing surface for the back of the slotted focus ring  226  to rotate against. The rear focus ring  222  can also be combined with the front portion of the ball  242  or separate from the ball  242  for the sake of a employing a more precise bearing surface and for providing a high quality look and feel to the assembly. The slotted focus ring  226  is a front to back focus mechanism engaged with the adapter  212 , which holds in place the interchangeable optical assembly  210  and allows the optics to be adjusted in a front to back manner in the direction of the tilt of the optics assembly  210  in relation to the imaging surface. 
     The slotted focus ring  226  includes a slot having a variable angle (e.g., a variable radius of curvature) that allows for more gradual focus adjustments as the lens focuses on subject matter closer to infinity, while more rapid adjustments to be made when the lens focuses on subject matter which is closest to the camera. The focus sleeve  224  provides grip and backbone for the slotted focus ring  226 . For example, the focus sleeve  224  can provide a rigid and tactile area where the user turns the outside rubberized surface of the focus sleeve  226  which internally grips the slotted focus ring  226  and provides the slotted focus ring  226 , which on its own is quite limber and flexible, with a rigid backing thereby providing a precise and secure adjustable track for the adapter  212  which holds in place the interchangeable optical assembly  210 . 
     The collar  228  can be a foundation for the focus mechanism and provide a straight front to back track that maintains the alignment of the optical assembly  210  while connecting the ball  242  to the front capture of the slotted focus ring  226 , focus sleeve  224 , and adapter  212 . The front focus ring  230  can be an extension of the collar  228  where it meets the front of the focus sleeve  224  thereby allowing a precise and durable surface to serve as the faceplate of the optical assembly  210 . 
     In one embodiment, the optical assembly  210  includes the adapter  212  and an optical cup  214 . The adapter  212  facilitates the interchangeable optical assemblies and travels forward and backward inside the collar  228  when the focus sleeve  224  is turned by the user rotating the slotted focus ring  226  which couples with three pins of the adapter  212 . The optical cup  214  has a housing  215  that carries an optic  217 . The optical cup  214  removably attaches to the adapter  212  (as discussed in greater detail below) that securely holds the optical cup and associated optic in proper position within the lens assembly  100 . In one embodiment, the adapter  212  integrates a bayonet-type system including three L shaped internal cutouts in the adapter  212  and three spring loaded raised bumps that couple with three tabs and one to three recesses or channels  219  in the interchangeable optical assembly housing. The adapter  212 , along with the necessary interface on the interchangeable optical assemblies, allows for secure mounting and simple swapping of optical assemblies. 
       FIG. 3  is a side view of an optical cup  214  in accordance with an embodiment of the present invention, and  FIG. 4  is a top end view of the optical cup of  FIG. 3 . The optical cup  214  has the housing  215  with a narrowed bottom portion  300  and an open top portion  302 . The optic  217  of the illustrated embodiment is carried in the housing&#39;s bottom portion  300  and in axial alignment with the housing  215 . In one embodiment an optic ring  301  is positioned within the housing  215  adjacent to the optic  217  so as to fixedly hold the optic in the housing. The optic ring  301  of the illustrated embodiment is securely connected to the housing by a pressure or friction fit, although other techniques could be used to hold the optic ring in place. In the illustrated embodiment, the housing  215  and the optic ring  301  are configured to receive and removably retain an aperture disc next to the optic. In the embodiment of  FIG. 4 , the optic ring  301  includes one or more magnets  305  positioned to engage and hold the aperture disc in place once installed. In other embodiments, other holding techniques can be used to removably retain an aperture disc on the optic ring  301  next to the optic  217 . 
     The housing&#39;s open top portion  302  has a threaded inner surface  304  with threads  306  adjacent to a top edge  308  of the housing  215 . The open top portion  302  of the housing is configured to removably receive any of a plurality of filters that screw onto the threads  306  and extend across the open top portion in axial alignment with the optic  217 . While the illustrated embodiment has threads  306  on the housing to removably receive a filter, other attachment mechanisms or systems can be used to attach a filter to the optical cup in alignment with the optic  217 . 
     It is noted that the terms “top” and “bottom” are used in conjunction with the view of the optical cup for purposes of providing a frame of reference for purposes of discussion. It is to be understood that, in use, a “top” structure could be above, below, left, right, or a combination of these directional terms (relative to vertical) of a “bottom” structure depending upon the orientation of the optical cup or lens assembly relative to vertical. 
     The optical cup  214  has an engagement ring  310  with a beveled or tapered lower potion  312  and a top radial flange  314  that is substantially coplanar with the top edge  308  of the housing  215 . The radial flange  314  of the illustrated embodiment has one or more cutouts  315  configured to receive protrusions on a spanner  216  ( FIG. 2A ) or other tool used install or remove the optical cup from the adapter  212  of the optical assembly  210 . The engagement ring  310  of the illustrated embodiment also has radially projecting tabs  316  intermediate the beveled lower portion  312  and the top radial flange  314 . The tabs  316  are shaped and sized to slide along the tracks or channels  219  in the adapter  212  ( FIG. 2 ) and to releasably retain the optical cup  214  in an installed position in the lens assembly  100  (as shown in  FIG. 7 ). 
     The optical cup  214  of the illustrated embodiment has a lower retaining ring  320  positioned between the outer surface of the housing  215  and the beveled lower portion  312  of the engagement ring  310 . The lower retaining ring  320  in one embodiment is sized to extend below the engagement ring  310  so the lower retaining ring is visible. The optical cup  214  of the illustrated embodiment also has an upper retaining ring positioned between the open top portion  302  of the housing and the top radial flange  314  of the engagement ring  310 . In one embodiment, a portion of the upper retaining ring  322  is also visible to a person looking at the open top portion  302  of the housing when the optical cup  214  is installed. The upper and lower retaining rings assist in retaining the engagement ring  310  in a fixed position on the housing  215 . 
     Different optical cups  214  can be provided with different optics  217 . For example, the optical cup can include any one of a plastic element, single glass element, double glass element, fish-eye, wide angle, or any other selected lens element or grouping of lens elements that focuses light to create an image on film or an imaging plane. One optical cup can include a first type of an optic, and other optical cups (interchangeable with any of the other optical cups) can include different optics. Accordingly, a user can easily and quickly change optical cups  214 , such as if the user wants to take pictures using different techniques. 
       FIGS. 5A-C  are top, side, and bottom views of different optical cups  214  that contain different optics  217  (i.e., the optics have different optical characteristics). In the illustrated embodiment, the optical cups  214  are color coded by providing upper and/or lower retaining rings  320  and  322  of a selected color used to signify the characteristic of the optic in that optical cup. Accordingly, a user will know (or learn) that an optical cup with yellow upper and/or lower retaining rings has one type of optic, and an optical cup having a different colored upper and/or lower retaining rings (e.g., blue, pink, black, white, etc.) will have an optic with a different characteristic. This color coding of the optical cups allows a user to easily identify and select which optical cup he or she desires to obtain photographs using a desired photographic technique. While the illustrated embodiment has the color coded optical cups  214 , other embodiments need not include the color coding. In one embodiment, indicia, such as text, symbols, etc., can be provided on the exterior of the optical cup  214 , wherein the indicia provides a visual indication of the type of optic is in the optical cup. The indicia can be color coded or not. 
       FIG. 6  is a side view of the optical cup  214  of  FIG. 3  adjacent to a carrying assembly  324 . The carrying assembly has a clear container portion  326  configured to allow a user to see an optical cup  214  contained therein. In the embodiment wherein the optical cups  214  are color coded, a user can see through the container portion  326  and easily determine which type of optical cup is in the carrying assembly. 
     In the illustrated embodiment, the carrying assembly  324  has a top portion  328  separable from the container portion  326 . In the illustrated embodiment, the top portion  328  of the carrying assembly  324  (show in  FIG. 6  askew from the container portion) is configured with an integral tool  332  that can act as an optical cup release to install or remove the optical cup  214  from the adapter  212  ( FIG. 2 ). The illustrated tool  332  is a spanner with a plurality of radially disposed tabs that fit into slots formed in the top radial flange  314  of the engagement ring  310 . Accordingly, a user can the use the tool  332  to engage and rotate the optical cup  214  to release or engage the optical cup with the adapter  212  ( FIG. 2 ). In other embodiments, other tools separate from the carrying assembly  324  can used to interchange optical assemblies. Alternatively, the optical cup can be configured for removal or installation without using a tool (i.e., tool-less installation or removal). 
       FIG. 7  is a view of lens assemblies with optical cups installed therein in accordance with an embodiment of the invention. The optical cups  214  of the illustrated embodiment can have a common size so as to be useable in the tilt assembly  240  and in other lens assemblies (tiltable or non-tiltable). 
     The embodiments described above provide several novel features. For example, the illustrated assembly  100  provides interchangeable optical assemblies. The interchangeable optical assemblies can include a quick release of an optical assembly from the body of a tilt/focus mechanism, while the focusing mechanism stays with the main body of the assembly. Because the optical cup is removable and interchangeable, the focus and tilt mechanism can remain with the camera while the lens and aperture can be separated and interchangeable. This differs from existing tilt systems with interchangeable optical assemblies that contain a focus mechanism housed within each interchangeable optical assembly. 
     The embodiments disclosed herein also provide for a variable angle of slots in the slotted focus sleeve. For example, the radius of curvature in the slot of the focus sleeve can change (e.g., the radius of curvature can be larger or smaller) at the end portions and/or middle portions of the slot. The variable angled slots allow for more precision focusing closer to infinity. In contrast, precise manual focus in existing focus mechanisms is compromised by focus adjustments that are overly coarse when focusing on distant subjects, and overly precise when focusing on up-close subjects 
     The embodiments disclosed herein also provide for a fluidly adjustable ball in socket tilt mechanism allowing up to about 17 degrees in one direction (i.e., for a total of about 34 degrees of tilt from one extreme to another) of total tilt off parallel of the lens elements. 
     The embodiments disclosed herein also include a tension adjustment providing the ability to lock the tilt mechanism down completely. 
     The embodiments disclosed herein further provide a minimum tension on lock and tilt mechanism controlled by the use of compression springs holding the ball with consistent tension independent of imperfections in the symmetry of the ball&#39;s outer surface. 
     In operation, the tensioning assembly is rotated to put the ball in its least tensioned position in order to allow for easy manual adjustments of the ball socket tilt assembly. In order to achieve a certain desired effect, the ball can be pushed from one side or another side to bring the lens elements into a parallel state with the image plane or to move the lens elements off parallel with the camera&#39;s image plane in the amount desired by the user. The focus sleeve can also be turned to bring the desired portion of the image into sharp focus, and once the image has been focused and the user has decided that the tilt is correct for the shooting situation the user may choose to rotate the tensioner in order to put the ball in its most tensioned position so as to protect the lens from being inadvertently moved from this ideal position. 
     If the user so chooses, the interchangeable optical assembly may be removed by the user and a new optical assembly may be put in its place to achieve a look and feel that is unique to the new interchangeable lens assembly. Pictures may be taken throughout this process to determine proper focus, exposure, etc.