A variable magnification optical system with boresight error correction includes a focusing lens to receive light along an optical axis of the variable magnification optical system, with the focusing lens configured to create an image of a target at a focal plane. The system includes a magnification changer disposed along the optical axis, with the magnification changer including an optomechanical drive system to adjust an optical magnification setting of one or more zoom lenses. The system also includes a light source configured to emit a pilot beam into the magnification changer. The system includes a position sensitive photodetector configured to receive the pilot beam exiting the magnification changer. The system further includes a microdisplay optically conjugate to the focal plane, with the microdisplay configured to impose an image of an electronic reticle on the focal plane based on the position of the pilot beam relative to the position sensitive photodetector.

A digital booster for an optical system includes an image acquisition unit. The image acquisition unit is configured to acquire an image frame from a non-magnified optic. The image frame includes an aiming reticle imposed by the non-magnified optic. The digital booster includes a display and a processor. The processor is configured to locate the aiming reticle on the image frame, select a sub-frame of the image frame with an aspect ratio that is centered on the aiming reticle of the image frame, perform image inversion and rescaling of the sub-frame, and transmit the sub-frame to the display.

A digital booster for an optical system includes an image acquisition unit. The image acquisition unit is configured to acquire an image frame from a non-magnified optic. The image frame includes an aiming reticle imposed by the non-magnified optic. The digital booster includes a display and a processor. The processor is configured to locate the aiming reticle on the image frame, select a sub-frame of the image frame with an aspect ratio that is centered on the aiming reticle of the image frame, perform image inversion and rescaling of the sub-frame, and transmit the sub-frame to the display.

A variable range compensating device, including at least some of a housing having an optical cavity defined at least partially within the housing, wherein the optical cavity extends from an incoming image aperture to an outgoing image aperture; and two or more reflective optical elements, wherein each reflective optical element is adjustably positioned within at least a portion of the optical cavity, and wherein adjustment of at least one of the reflective optical elements adjusts the reflective optical elements such that a target image entering the incoming image aperture is reflected by the reflective optical elements, so as to exit the outgoing image aperture at a determined offset.

A variable range compensating device, including at least some of a housing having an optical cavity defined at least partially within the housing, wherein the optical cavity extends from an incoming image aperture to an outgoing image aperture; and two or more reflective optical elements, wherein each reflective optical element is adjustably positioned within at least a portion of the optical cavity, and wherein adjustment of at least one of the reflective optical elements adjusts the reflective optical elements such that a target image entering the incoming image aperture is reflected by the reflective optical elements, so as to exit the outgoing image aperture at a determined offset.

A reticle has a horizontal stadia line and a vertical stadia line. A plurality of elevation subtension markings having a thickness are connected to the vertical stadia line. A plurality of fine subtension markings are positioned along the horizontal stadia line. A plurality of coarse subtension markings are positioned along the horizontal stadia line. The thickness of the coarse subtension markings is greater than the thickness of the fine subtension markings. A Christmas tree dot pattern is provided below the horizontal stadia line with a hold point feature within a lower portion of the Christmas tree dot pattern.

A reticle has a horizontal stadia line and a vertical stadia line. A plurality of elevation subtension markings having a thickness are connected to the vertical stadia line. A plurality of fine subtension markings are positioned along the horizontal stadia line. A plurality of coarse subtension markings are positioned along the horizontal stadia line. The thickness of the coarse subtension markings is greater than the thickness of the fine subtension markings. A Christmas tree dot pattern is provided below the horizontal stadia line with a hold point feature within a lower portion of the Christmas tree dot pattern.

A compensating mechanism includes a base unit, a transmission unit, an adjusting cap and a rotation setting unit. The base unit includes a grooved portion that includes a first groove and a second groove communicated with the first groove. The second groove includes a first end and a second end opposite to the first end. The first end is connected to the first groove. The first end and the second end have a height difference therebetween in an axial direction of the base unit. The transmission unit is disposed on the base unit. The adjusting cap is connected to the transmission unit. The adjusting cap drives the transmission unit to rotate when the adjusting cap is rotated. The rotation setting unit includes a movable element that is movably disposed on the transmission unit to be connected to the grooved element or to be separated from the grooved element.

An optical apparatus flexible stop has a flexible surface element, which is flat/planar in a first state and rolled or wound into a hollow roll in a second state. Two tensioning cords guide around the hollow roll to hold the hollow roll shape. An optical apparatus is provided with a tubular body containing an optical unit and having a first open tube end, an attachment device having a device housing, wherein an optical through passage of the device housing is arranged in front of the open tube end, and the flexible stop. The flexible stop is rolled or wound around the open tube end of the tubular body and the optical through passage of the device housing, held in the shape of a tube with the tensioning cords, thus forming an optical tunnel between the open tube end and the optical through passage.

An optical apparatus flexible stop has a flexible surface element, which is flat/planar in a first state and rolled or wound into a hollow roll in a second state. Two tensioning cords guide around the hollow roll to hold the hollow roll shape. An optical apparatus is provided with a tubular body containing an optical unit and having a first open tube end, an attachment device having a device housing, wherein an optical through passage of the device housing is arranged in front of the open tube end, and the flexible stop. The flexible stop is rolled or wound around the open tube end of the tubular body and the optical through passage of the device housing, held in the shape of a tube with the tensioning cords, thus forming an optical tunnel between the open tube end and the optical through passage.