Optical loop safety measure isolation detecting tool

The invention discloses an optical loop safety measure isolation detecting tool, which comprises a main component, a connecting component and a locking component. A fiber hole penetrating an output fiber is formed in the middle of the main component. The main component includes a transmission sleeve. An input fiber penetrates the connecting component; and the input fiber and the output fiber are arranged coaxially. The connecting component is installed at the main component movably along the axial direction of the output fiber by the locking component and moves along the axial direction of theoutput fiber, thereby adjusting the space between the output fiber and the input fiber. The transmission sleeve sleeves the output fiber. When the output fiber and the input fiber are in butt joint,light from the output fiber is transmitted to the outer side of the main component through the transmission sleeve. The output fiber carries out guiding orientation by the main component; and the input fiber carries out guidin