Dual reticle device and assembling method thereof

A method of assembling a dual reticle device, comprising the steps of:

• providing a ring structure having a first ring end-surface, a second ring end-surface and an outside surface, wherein the outside surface joins the first ring end-surface and the second ring end-surface together and the ring structure has an axis perpendicular to the first ring end-surface and the second ring end-surface;
• forming a pair of first positioning grooves and a pair of second positioning grooves on the outside surface of the ring structure, wherein the first positioning grooves and the second positioning grooves are parallel to the axis of the ring structure and set on the outside surface;
• mounting a first reticle on the first ring end-surface of the ring structure such that the line joining the first and second positioning grooves on the first ring end-surface coincide with the first reticle;
• and
• mounting a second reticle on the second ring end-surface of the ring structure such that the line joining the first and second positioning grooves on the second ring end-surface coincide with the second reticle, wherein the first reticle coincides with the second reticle in the axial direction of the ring structure.

A method of assembling a dual reticle device, comprising the steps of:

• providing a ring structure having a first ring end-surface, a second ring end-surface and an outside surface, wherein the outside surface joins the first ring end-surface and the second ring end-surface together and the ring structure has an axis perpendicular to the first ring end-surface and the second ring end-surface;
• forming a pair of first positioning grooves and a pair of second positioning grooves on the outside surface of the ring structure, wherein the first positioning grooves and the second positioning grooves are parallel to the axis of the ring structure and set on the outside surface;
• wrapping a first wire around the ring structure such that a portion of the first wire is disposed within one of the first positioning grooves and the two ends of the first wire is disposed within the other first positioning groove so that a first vertical wire and a second vertical wire are formed on the first ring end-surface and the second ring end-surface, wherein the first vertical wire and the second vertical wire coincide with each other in the axial direction of the ring structure;
• fastening the first wire to the ring structure;
• wrapping a second wire around the ring structure such that a portion of the second wire is disposed within one of the second positioning grooves and the two ends of the second wire is disposed within the other second positioning groove so that a first horizontal wire and a second horizontal wire are formed on the first ring end-surface and the second ring end-surface, wherein the first horizontal wire and the second horizontal wire coincide with each other in
• the axial direction of the ring structure;
• and
• fastening the second wire to the ring structure.