Abstract:
A stereoscopic viewing apparatus for viewing side-by-side complimentary stereoscopic image pairs of various sizes to produce a three-dimensional effect, the stereoscopic viewing apparatus comprising a pair of left and right spaced-apart ocular windows and variable septa.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S)  
       [0001]    This application claims the benefit of U.S. Provisional Patent Application No. 60/144,851 filed on Jul. 20, 1999. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The present invention relates to the field of stereoscopes. In particular, the present invention relates to a prism stereoscope for viewing stereoscopic image pairs.  
           [0003]    Stereoscope viewing apparatuses have been known since 1833 when Sir Charles Wheatstone, a British inventor, came up with the idea of using drawings and a viewing device to produce three dimensional images. The drawings included two side-by-side complementary images, each image drawn from a slightly different perspective. When placed a fixed distance from a users eyes, and with the help of a septum, the images fuse together to produce a three dimensional effect.  
           [0004]    As the stereoscope technology advanced, side-by-side complementary photographs took the place of the drawings. Over the years, many types of stereoscopes have been used. The following patents describe such examples:  
                                                   INVENTOR   PAT. NO.                           Wagner     502,450           Maerz   1,097,601           Murphy   1,194,057           Barr et al.   1,743,952           Schlienger   3,592,524           Lewis   3,847,467           Thompson   4,124,798           Carver   4,253,732           Pryor   4,457,584           Vitrac   4,549,785           Chevalier   4,660,931           Brown   4,998,799           Christian   5,270,751           Sullivan et al.   5,384,655           Gilchrist   5,615,046           Huang   5,943,165           Johnson et al.   5,954,642           Cunanan   6,046,850                      
 
           [0005]    The side-by-side format is a popular method of displaying stereo-paired images. Commercial stereoscopes, such as the Holmes/Bates and Viewmaster® stereoscopes typically contain lenses combined with prisms. Lenses magnify the images and allow the user to focus on the images a few inches from the user&#39;s eyes. The prisms also translate the images to the center of the user&#39;s field of view. This aids the user in fusing the images in binocular vision.  
           [0006]    Many commercial stereoscopes incorporate prisms intrinsically as a property of the lens. Lenses in stereoscopes define a limited range of viewing distances for which the user can focus on stereoscopic images. The limited range, together with the amount of prism action, define the maximum separation of the images that can be fused. Therefore, either the stereoscope determines the allowable image separations or the image separation determines the required properties of the stereoscope.  
           [0007]    The use of standard image sizes became popular early on in order to allow standard stereoscopes to be used to view many images. However, images are increasingly being printed or viewed in non standard sizes. Non-standard sized images are frequently encountered when a computer monitor is used to view the stereo-images. This is because the size of the images depends on the properties of the monitor, including monitor settings such as pixel density, and the pixel dimensions of the images. Stereoscopes often use a septum to block out the periphery around the images including the well-known side images which cause visual rivalry between the left and the right views. The optimal dimensions of the septa are determined by the distance between the stereoscope and the stereo-image pairs and the properties of the lenses. In traditional stereoscopes, the septum has a fixed geometry.  
           [0008]    To aid the viewing of non-standard size images, various stereoscopes have been designed using prisms or mirror boxes. Mirror boxes typically allow large images of a particular size to be viewed at any distance. If the mirror box can be translated outward, a range of large image sizes can be used at any reasonable distance. However, mirror box stereoscopes are typically as wide as the distance between the centers of the images being viewed.  
           [0009]    Stereoscopes which use prisms but no lenses can be used to view images of any size from the common standard print sizes up to arbitrarily large sizes. The user adjusts the viewing distance until the stereo images fuse together. Prism stereoscopes often include masks to block out the well known side images which create vision disparities between the left and right eyes. Ideally, the masks should block out all of the periphery from the fused image.  
         BRIEF SUMMARY OF THE INVENTION  
         [0010]    The present invention is a stereoscopic viewing apparatus for viewing side-by-side complimentary pairs of stereo images. The stereoscopic viewing apparatus of the present invention includes a pair of ocular members and a pair of objective members. In use, the ocular members are placed proximate to a user&#39;s eyes, and the objective members are adjusted to define a field of view. The objective members are adjusted depending upon the size of the stereo images and the distance the stereo images are from the viewing apparatus. With the objective members properly adjusted, the user perceives a three-dimensional image. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    [0011]FIG. 1 is a perspective view of the present invention in a fully open coupled state.  
         [0012]    [0012]FIG. 2 is a partial sectional side view of the present invention in the fully open coupled state.  
         [0013]    [0013]FIG. 3 is a perspective view of the present invention in a closed uncoupled state.  
         [0014]    [0014]FIG. 4 is a side view of the present invention in a second coupled position.  
         [0015]    [0015]FIG. 5 is an ocular view of the present invention in the fully opened coupled state.  
         [0016]    [0016]FIG. 6 is a plan view of a support arm cooperation.  
         [0017]    [0017]FIG. 7 is a plan view of a support arm cooperation.  
         [0018]    [0018]FIG. 8 is a side view of the present invention in a position between the fully open position and the closed position.  
         [0019]    [0019]FIG. 9 is a plan view of a backside of the present invention 
     
    
     DETAILED DESCRIPTION  
       [0020]    The stereoscopic viewing apparatus of the present invention is indicated generally at  10  in FIG. 1. The stereoscopic viewing apparatus  10  is a binocular apparatus including a first pair of left and right spaced-apart ocular members  12 ,  14  respectively, and a second pair of left and right spaced-apart objective members  16 ,  18 , respectively. Each member  12 ,  14 ,  16 ,  18  is hingedly attached to a common linkage  20 . The stereoscopic viewing apparatus could also be described as having left and right optical systems, each with a focal point near infinity.  
         [0021]    Each ocular member  12 ,  14  includes a surface  22 ,  23  defining a left ocular window  24  and a right ocular window  26 , respectively. Prism lenses  28 ,  30  are positioned proximate to the left and right ocular windows  24 ,  26 , respectively, as illustrated in FIG. 2. Each prism lens  28 ,  30  cooperates with the respective ocular window  24 ,  26 , and has a substantially infinite focal length. A person skilled in the art will realize that the prism lenses  28 ,  30  can have either curved or flat surfaces.  
         [0022]    Preferably, the ocular members  12 ,  14  further include masking walls  32 ,  34  attached thereto. The masking walls  32 ,  34  aid in shrouding the left and right windows  24 ,  26  of the respective ocular members  12 ,  14  thus restricting the amount of light allowed through the ocular windows  24 ,  26 . It is also preferable to have each ocular member  12 ,  14  formed from a single piece of suitable plastic material.  
         [0023]    The second pair of left and right spaced-apart objective members  16 ,  18  have an L-shaped configuration, including a first leg  36 , 37  and a second leg  38 ,  39 , respectively. Each objective member  16 ,  18  acts as a septum and is rotatably adjustable about the linkage  20 . The left objective member  16  cooperates with the left ocular member  12 , while the right objective member  18  cooperates with the right ocular member  14 . A person skilled in the art will appreciate the advantages of having adjustable septa when viewing stereo-image pairs of varying sizes.  
         [0024]    Preferably, the second legs  38 ,  39  of the left and right objective members  16 ,  18  each include a surface  42 ,  44  defining a left objective window  46  and right objective window  48 , respectively. The left objective window  46  cooperates with the left ocular window  24  defining a left field of view. The right objective window  48  cooperates with the right ocular window  26  defining a right field of view. Each objective window  46 ,  48  is of a larger size relative to the corresponding ocular windows  24 ,  26 .  
         [0025]    Each objective member  16 ,  18  further includes a first wall  50 ,  52  and a second wall  54 ,  56 . Each wall  50 ,  54  and  52 ,  56  attaches to an edge of the first and second legs  36 ,  38  and  37 ,  39  of the objective members  16 ,  18  respectively, which restricts the amount of light allowed to reach the ocular windows  24 ,  26 . The walls also provide surfaces for gripping and handling the stereoscopic viewing apparatus  10 . Preferably, each objective member  16 ,  18  is formed as a single piece from a suitable plastic such as by molding. In one embodiment, the walls  50 ,  52 ,  54 ,  56  have a textured surface or an anti-reflective coating to restrict unwanted reflections through the ocular windows  24 ,  26 .  
         [0026]    The common linkage  20  of the stereoscope viewing apparatus  10  allows the members  12 ,  14 ,  16 ,  18  to rotate about a hinge  58  in a coupled state or an uncoupled state. In the uncoupled state, each member  12 ,  14 ,  16 ,  18  is rotatable about hinge  58  over a range which includes a first closed position, as shown in FIG. 3. In the first position, the objective members  16 ,  18  enclose the ocular members  12 ,  14 . The first position is the preferred position for storing or carrying the stereoscopic viewing apparatus  10  when not in use.  
         [0027]    In the coupled state, the rotations of the left and the right ocular members are coupled to the rotations of the respective objective members  16 ,  18 , and thus each ocular member  12 ,  14  remains at a fixed orientation with respect to the respective objective members  16 ,  18  independent of rotational position. FIGS. 1, 2,  4  and  5  show the stereoscope viewing apparatus  10  in the coupled state for two rotational positions. Preferably, the second legs  38 ,  39  of the objective members  16 ,  18 , including the objective windows  46 ,  48 , are positioned substantially parallel to the respective ocular members  12 ,  14  while coupled. However, some variation in the position of the second legs  38 ,  39  of the objective members  16 ,  18  while coupled with the ocular members  12 ,  14  is within the scope of the present invention.  
         [0028]    The rotations of the ocular members  12 ,  14  and objective members  16 ,  18  are further linked by stops  80  shown in FIGS. 5, 9 and  10 . The stops  80  cause the ocular members to rotate from the uncoupled state into the coupled state when the objective member  16 ,  18  are rotated from the closed position shown in FIG. 3 to the fully opened shown in FIGS. 1, 2 and  5 . The stereoscope apparatus  10  changes from the coupled state to the uncoupled state when the objective members  16 ,  18  are rotated from the orientation shown in FIG. 8 to the closed position shown in FIG. 3. Thereby, full operation of the stereoscope apparatus  10  can be carried out by actively rotating the objective members  16 ,  18  without the need to actively rotate or handle the ocular members  12 ,  14 .  
         [0029]    With the left and right ocular members  12 ,  14  coupled to the respective objective members  16 ,  18 , the left objective window  46  cooperates with the left ocular window  24 , and the right objective window  48  cooperates with the right ocular window  26 . When coupled, rotating either objective member  16 ,  18  also rotates the corresponding coupled ocular member  12 ,  14 .  
         [0030]    The objective members  16 ,  18  are linked to the respective ocular members  12 ,  14  by the common linkage system  20 . The common linkage system  20  includes a plurality of support arms  40 ,  41  as illustrated in FIGS. 1, 3 and  5 . Preferably, there are two support arms  40  or  41  attached to each member  12 ,  14 ,  16 ,  18 . Each support arm  40 ,  41  is attached to a member  12 ,  14 ,  16 ,  18  and includes an aperture  64  therethrough. The apertures  64  within the support arms  40 ,  41  are aligned to collectively define a through-bore  66 , into which a cylindrical pin  68  is inserted to operably connect each support arm  40 ,  41 . Preferably, each end of the cylindrical pin  68  is crimped to keep the pin  68  operably connected to each support arm  40 ,  41 . However, other means such as a threaded nut and bolt may be used to operably connect the support arms  40 ,  41 .  
         [0031]    There are two basic configurations for the support arms  40 ,  41 . The support arms  41  attached to the ocular members  12 ,  14  have a bent configuration, as illustrated in FIGS. 6 and 7, while the support arms  40  attached to the objective members  16 ,  18  have a straight configuration, as illustrated in FIGS. 6 and 7.  
         [0032]    The support arms  40 ,  41  are positioned adjacent to one another, as best illustrated in FIG. 5. The support arms  40 ,  41  are ordered along the pin  68  so that the support arms  41  attached to the ocular members are near the middle of the pin  68  while the support arms  40  attached to the objective members are near the ends of the pin. The first legs  36 ,  37  of the objective members  16 ,  18  have surfaces X, Y which define through spaces W, V for the ocular support arms  41  to pass through as illustrated in FIG. 9.  
         [0033]    Engagement dentation  70  are positioned on the ocular support arms  41  such that in the coupled state, an engagement detention  70  is directly adjacent to each side of the surfaces X, Y on legs  36 ,  37 . The surfaces X, Y preferably have a denticular profile. The detention  70  elastically engages the legs  36 ,  37  thereby causing the rotation of the ocular members  12 ,  14  to be coupled to the rotation of the objective members  16 ,  18 , respectively.  
         [0034]    The support arms  41  additionally have stops  80  which couple the rotation of the left objective member  16  to the right ocular member  14  and the right objective member  18  to the left ocular member  12 . The location of the stops  80  are best seen in FIG. 5. The engagement of the stops  80  is best seen in FIGS. 6 and 7. As the stereoscope apparatus  10  transitions between the coupled and uncoupled states, the linkage system  20  must elastically deform as the surfaces X, Y slide over the dentation  70 . This elastic deformation requires that extra force be applied by the user. When transitioning into the uncoupled state from the position shown in FIG. 8, the extra force can be applied directly to the objective members  16 ,  18  by pushing them inward. When transitioning into the coupled state in the fully opened position shown in FIGS. 1, 2, and  5 , the extra force applied to the objective members  16 ,  18  is transferred to the ocular members  14 ,  12 , respectively through the stops  80 .  
         [0035]    As the objective members  16 ,  18  are rotated from the first position as illustrated in FIG. 3 to the fully opened position as illustrated in FIGS. 1, 2 and  5 , the coupled state is preferably reached when the left and the right ocular members  12 ,  14  have approximately 180 degrees of rotation relative to each other, and the left and right member  16 ,  18  have approximately up to 270 degrees of rotation relative to each other.  
         [0036]    Once the left and right ocular members  12 ,  14  are coupled to the respective cooperating objective members  16 ,  18 , the left ocular member  12  and left objective member  16  are adjustable with respect to the right ocular member  14  and right objective member  18 . The left and right ocular members  12 ,  14  remain coupled with the respective left and right objective members  16 ,  18  through approximately the first 180 degrees of rotation from the fully opened position toward the closed position. Near 180 degrees of rotation, the left and right ocular members contact each other as illustrated in FIG. 8. When a sufficient force is applied to the objective member  16 ,  18 , the elastic engagement is overcome, thus de-coupling the left and right ocular members  12 ,  14  from the respective objective members  16 ,  18 . The objective members  16 ,  18  can then be rotated to the first position, after which the objective members  16 ,  18  enclose the ocular members  12 ,  14 , as illustrated in FIG. 3. The objective windows  46 ,  48  act as adjustable masks. The rotation of the objective members  16 ,  18  near the fully opened position provides a septum of varying width (which is analogous to a septum of varying length).  
         [0037]    The ocular windows  24 ,  26  of the present invention are of a width sufficient enough to accommodate a range of distances between the user&#39;s left and right eyes. As the objective windows  46 ,  48  are adjusted for a particular stereo-paired image, the separation between the ocular windows  24 ,  26  changes by a negligible amount, thereby continuing to accommodate a vast range of distances between the viewer&#39;s left and right eyes.  
         [0038]    As previously mentioned, the size of the objective windows  46 ,  48  is larger than the ocular windows  12 ,  14 . As the stereoscopic viewing apparatus  10  is positioned further away from a user&#39;s eyes, the fused three-dimensional image is cropped because the ocular windows  24 ,  26  are smaller than the objective windows  46 ,  48 . This compels the user to keep the stereoscopic viewing apparatus  10  a minimal distance from the user&#39;s eyes. By restricting the position of the stereoscopic viewing apparatus  10  proximate a user&#39;s eyes, the operation of the stereoscopic viewing apparatus  10  is stabilized. This stabilization of the operation of the stereoscope is the result of having separate ocular and objective elements whereby the objective elements are adjustable. The optimal adjustment of the objective windows  46 ,  48  is a function of the distance between the user and the stereo-paired images and the separation of the stereo-paired images.  
         [0039]    A person skilled in the art will appreciate that by fixing the position of the stereoscopic viewing apparatus  10  proximate a user&#39;s eyes, the operation of the, stereoscope  10  becomes much more intuitive. The user moves toward or away from the stereo-image pair being viewed in order to obtain the desired horizontal field of view of the stereo-image pair. The user then adjusts the separation of the objective windows  46 ,  48  to mask the periphery symmetrically around the stereo-images. The amount of adjustment depends upon the relative separation of the stereo image pairs.  
         [0040]    Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.