An optical system comprising: a single window; a detector; an optical assembly (106, 112, 114, 116, 118) that reflects light rays from a first, narrow, field-of-view through a first optical path to the detector; a field-of-view switch assembly (102, 202), comprising: a mount movably coupled to the optical assembly, the mount being selectively movable between a non-bypass position and a bypass position; a first diverter mirror (134a, 232a) attached to the mount; a second diverter mirror (134b, 232b) attached to the mount, wherein the first and second diverter mirrors are configured, when in the non-bypass position, to not receive, and not to be reflective of, light rays (132a-132c) through the first optical path, and to bypass the first field-of-view and translate a second, wide, field-of-view when moved from the non-bypass position to the bypass position, thereby redirecting light rays from the second field-of-view via the first and second diverter mirrors through a second optical path to the detector, such that the light rays through the second optical path through the single window are directly incident on and reflected by the second diverter mirror, and then directly incident on the first diverter mirror, and then reflected from the first diverter mirror directly to the detector; and a dynamic shutter movably coupled to the mount, wherein the dynamic shutter is configured to shield a reflective surface of the second diverter mirror from light rays when in the non-bypass position, and to expose the reflective surface when in the bypass position; wherein both the first field-of-view and the second field-of-view are through the single window; wherein the first and second diverter mirrors straddle the first optical path when in the non-bypass position; and wherein, when in the bypass position, the first diverter mirror is positioned within the first optical path and thereby blocks light rays along the first optical path associated from the first field-of-view from being reflected to the detector. a single window; a detector; an optical assembly (106, 112, 114, 116, 118) that reflects light rays from a first, narrow, field-of-view through a first optical path to the detector; a field-of-view switch assembly (102, 202), comprising: a mount movably coupled to the optical assembly, the mount being selectively movable between a non-bypass position and a bypass position; a first diverter mirror (134a, 232a) attached to the mount; a second diverter mirror (134b, 232b) attached to the mount, wherein the first and second diverter mirrors are configured, when in the non-bypass position, to not receive, and not to be reflective of, light rays (132a-132c) through the first optical path, and to bypass the first field-of-view and translate a second, wide, field-of-view when moved from the non-bypass position to the bypass position, thereby redirecting light rays from the second field-of-view via the first and second diverter mirrors through a second optical path to the detector, such that the light rays through the second optical path through the single window are directly incident on and reflected by the second diverter mirror, and then directly incident on the first diverter mirror, and then reflected from the first diverter mirror directly to the detector; and a dynamic shutter movably coupled to the mount, wherein the dynamic shutter is configured to shield a reflective surface of the second diverter mirror from light rays when in the non-bypass position, and to expose the reflective surface when in the bypass position; a mount movably coupled to the optical assembly, the mount being selectively movable between a non-bypass position and a bypass position; a first diverter mirror (134a, 232a) attached to the mount; a second diverter mirror (134b, 232b) attached to the mount, wherein the first and second diverter mirrors are configured, when in the non-bypass position, to not receive, and not to be reflective of, light rays (132a-132c) through the first optical path, and to bypass the first field-of-view and translate a second, wide, field-of-view when moved from the non-bypass position to the bypass position, thereby redirecting light rays from the second field-of-view via the first and second diverter mirrors through a second optical path to the detector, such that the light rays through the second optical path through the single window are directly incident on and reflected by the second diverter mirror, and then directly incident on the first diverter mirror, and then reflected from the first diverter mirror directly to the detector; and a dynamic shutter movably coupled to the mount, wherein the dynamic shutter is configured to shield a reflective surface of the second diverter mirror from light rays when in the non-bypass position, and to expose the reflective surface when in the bypass position; wherein both the first field-of-view and the second field-of-view are through the single window; wherein the first and second diverter mirrors straddle the first optical path when in the non-bypass position; and wherein, when in the bypass position, the first diverter mirror is positioned within the first optical path and thereby blocks light rays along the first optical path associated from the first field-of-view from being reflected to the detector.