Protective optical system with offset light path and fusible optical mirror

Claim 1

AN OPTICAL SYSTEM COMPRISING: AN OBJECTIVE LENS, A FUSIBLE SECOND SURFACE MIRROR ORIENTED AT AN ANGLE TO THE OPTICAL AXIS OF SAID OBJECTIVE LENS FOR DIVERTING THE PASSAGE OF LIGHT THROUGH THE OPTICAL SYSTEM FROM A STRAIGHT LINE, SAID FUSIBLE SECOND SURFACE MIRROR BEING POSITIONED AT THE FOCAL POINT OF SAID OBJECTIVE LENS AT WHICH THE FIRST IMAGE OF AN OBJECT INDEFINITELY FAR AWAY WOULD BE FORMED, SAID FUSIBLE SECOND SURFACE MIRROR BEING COMPRISED OF A THIN MEMBRANE OF MATERIAL CAPABLE OF FUSION AT A PREDETERMINED THERMAL ENERGY LEVEL OF THE LIGHT AT THE FOCAL POINT, A COATING OF SPECULAR MATERIAL ON THE REAR SURFACE OF SAID MEMBRANE TO PROVIDE A REFLECTING SURFACE SAID COATING BEING OF A THICKNESS TO RENDER THE REFLECTING SURFACE FULLY REFLECTIVE WHILE STILL BEING DEPENDENT UPON SAID MEMBRANE FOR STRUCTURAL SUPPORT, A TWO LENS ERECTING SYSTEM POSITIONED TO RECEIVE IMAGES REFLECTED FROM SAID FUSIBLE SECOND SURFACE MIRROR, AN OPTICALLY FLAT MIRROR POSITIONED AT AN ANGLE TO SAID TWO LENS ERECTING SYSTEM AT THE FOCAL POINT OF AN ERECTED IMAGE FROM SAID TWO LENS ERECTING SYSTEM, AND AN EYEPIECE POSITIONED TO RECEIVE IMAGES REFLECTED FROM SAID OPTICALLY FLAT MIRROR.