For safety, the accuracy and efficient surgical operation, the device and the method of improving are disclosed. The device of this disclosure is the optical fiber set which has asymmetric distal (2036) end constitution. The aforementioned optical fiber set includes the advanced fiber which is crooked. The description above the advanced fiber which is crooked, includes with the printing sleeve and the rotary possible connector. The aforementioned printing sleeve is provided is provided in the distal (2036) (output) edge of the aforementioned fiber the aforementioned advanced fiber and just as the part. The aforementioned rotary possible connector is provided on proximal (input) side. The fiber point and the organizational contact area which are provided in the distal (2036) end of the aforementioned point can be constituted, the form constitution (for example, convex condition point) which differs in order to improve focus quality and also. As for the aforementioned concave condition point, by the fact that emission emission or the extended beam point is achieved, the effect which is similar to the effect which can by the electronic instrument for the surgery is achieved. By the grip section, the ability where you twist the grip section and you turn is guaranteed. In another ideal execution form, by special constitution, twisting operation improves. It becomes possible, because of this, efficiency and easily arrives to organization of specification, to do the remedy which improves with these special functional (point and rotary possible connector which are crooked) both parties, vis-a-vis various conditions it becomes possible to remedy. Depending upon the operativity, twisting possibility and revolution of the optical fiber, the accuracy and it becomes possible for organization to grant the effect which improves. Because of this, remedy easier, quicker and it becomes possible to do more accurately. For example, this device, inserting in the cystoscope, also it is p
