Optical time domain reflecting (OTDR) meters; optical power meters; optical spectrum analyzers; optical apparatus and instruments, namely, optical fibers, connectors for optical fibers, modules of laser diodes, namely, LD Modules, photo-diode (PD) modules, laser source, optical switch module, optical attenuator module, Optical Couplers, optical-to-electronic and electronic-to-optical interface units; telecommunication machines and apparatus, namely, optical fiber communications network; measu...