Composite central beam tube type optical cable

The invention belongs to the technical field of optical cables, and discloses a composite central beam tube type optical cable, which comprises a loose tube, a protective shell, a plurality of first composite units and a plurality of second composite units, the first composite unit is composed of a first butterfly-shaped unit and a first extension strip, the second composite unit is composed of a second butterfly-shaped unit and a second extension strip, the first composite unit is composed of a first butterfly-shaped unit and a first extension strip, the protective shell is composed of an outer layer defined by an outer-layer protective body and an inner layer defined by an inner-layer protective body, and a first extension hole, a first outer hole, a first inner hole and a second extension hole are formed in the protective shell. A central hole is formed in the inner-layer protection body; the loose tube is located in the center hole, the second butterfly-shaped unit is located in the first inner hole, the