Collapsible Stereoscopic Viewer

Abstract

A collapsible stereoscope made of a stiff but bendable material. The stereoscope includes a front viewing panel with apertures for lenses, a rear picture holding panel, and bracing side walls, all integrally hinged to a bottom panel. Each bracing side wall varies in height so that it is tall enough in some regions to provide structural support, but short enough in other regions to reduce or prevent the casting of shadows on the stereogram. The length of each bracing side wall is longer than length of the bottom panel, so that when each bracing side wall is secured to the front panel, the bracing side walls bend in toward each other at a preformed folding crease which improves structural stability of the stereoscope, holds stereograms against the picture holding panel, and reduces shadowing on the stereogram. The collapsible stereoscope can be used as a greeting card.

I claim: 
     
         1 . A collapsible stereoscopic viewer having an open top, comprising:
 a front viewing panel having apertures for lenses;   a rear picture holding panel for placement of at least one stereogram;   a first bracing side wall having a first diagonal folding crease, and a second bracing side wall having a second diagonal folding crease, said first and second diagonal folding creases each traverse at least a portion of said first and second bracing side walls, respectively;   a bottom panel opposing an open top of the collapsible stereoscopic viewer when the collapsible stereoscopic viewer is in an assembled configuration;   two ocular lenses;   said bottom panel has a rear edge and a front edge, said rear edge being longer than said front edge,   said rear edge of said bottom panel is integrally hinged to said rear picture holding panel, and said front edge of said bottom panel is integrally hinged to said front viewing panel;   at a distance from said rear edge of between 28% to 34% of a height of said rear picture holding panel, each of said first and second bracing side walls have a height of between 28% and 34% of the height of said rear picture holding panel;   said first diagonal folding crease extends from a corner joining said picture holding panel and said first bracing side wall, and said second diagonal folding crease extends from a corner joining said rear picture holding panel and said second bracing side wall;   said first bracing side wall is detachably secured to said front viewing panel, and said second bracing side wall is detachably secured to said front viewing panel when said stereoscopic viewer is in its assembled conformation, said first and said second diagonal folding creases cause said first and said second bracing side walls to bend in toward each other;   whereby said first and second bracing side walls support said stereogram against said picture holding panel, have a height high enough to prevent said stereoscope from collapsing unintentionally, and have a height low enough to prevent shadowing caused by outside light passing over said first and second bracing side walls onto said stereogram.   
     
     
         2 . The stereoscopic viewer of  claim 1 , wherein a first portion of said first bracing side wall, and a second portion of said second bracing side wall are each longer than the distance from said rear edge to said front edge of said bottom panel, and wherein said first and second bracing side walls are predisposed to bend inward relative to each other along said first and second diagonal creases, respectively, when the stereoscopic viewer is in its assembled configuration. 
     
     
         3 . The stereoscopic viewer of  claim 2 , wherein said first portion of said first bracing side wall is from a first recess on said first bracing side wall to a rear first vertical leg of said first bracing side wall, and said second portion of said second bracing side wall is from a second recess on said second bracing side wall to a rear second vertical leg of said second bracing side wall. 
     
     
         4 . A collapsible stereoscopic viewer having an open top, comprising:
 a front viewing panel having apertures for lenses;   a rear picture holding panel for placement of at least one stereogram;   a first bracing side wall having a first diagonal folding crease, and a second bracing side wall having a second diagonal folding crease, said first and second diagonal folding creases each traverse at least a portion of said first and second bracing side walls, respectively;   a bottom panel opposing an open top of the collapsible stereoscopic viewer when the collapsible stereoscopic viewer is in an assembled configuration;   two ocular lenses;   said bottom panel has a rear long edge of approximately 6 inches in length, a front short edge of approximately 5.5 inches in length parallel to said rear long edge, the distance from said rear long edge to said front short edge is approximately 5.5 inches;   said first bracing side wall and said second side bracing wall each have a height of approximately 1.25 inches at a distance of 1.25 inches from a vertical plane formed by said rear picture holding panel when said stereoscopic viewer is assembled;   said first diagonal folding crease is approximately 1.75 inches and extends from a corner joining said picture holding panel and said first bracing side wall, and wherein said second diagonal folding crease is approximately 1.75 inches and extends from a corner joining said picture holding panel and said second bracing side wall;   said first bracing side wall has a first recess, and said second bracing side wall has a second recess, said first and second recesses allow said front viewing panel to be detachably secured with said first and said second bracing side walls;   said first and said second recesses are positioned such that when said collapsible stereoscopic viewer is assembled, at least a portion of said first and said second bracing side walls angle in toward each other; and,   whereby said stereoscopic viewer is optimal for preventing shadows from forming on a 4 by 6 inch stereogram, and for preventing said first and said second bracing side walls from falling in towards each other.   
     
     
         5 . The stereoscopic viewer of  claim 4 , wherein at least a portion of said first bracing side wall and at least a portion of said second bracing side wall are each longer than the distance from said rear long edge to said front short edge of said bottom panel, and wherein said first and second bracing side walls are predisposed to bend inward relative to each other along said first and second diagonal creases, respectively, when the stereoscopic viewer is in its assembled configuration.