FIELD: optical instruments. SUBSTANCE: device has optical fiber, which optical features include at least one break which violates conditions of complete internal reflection of optical fiber in order to attenuate optical signal which is transmitted through optical fiber. Said break is caused by alteration in refraction index of core and jacket layer of optical fiber. Another claim of invention also discloses method for manufacturing of optical attenuator. EFFECT: increased functional capabilities. 14 cl, 6 dwg
