Scientific apparatus and instruments, optical, nautical and surveying components, namely, fiber-optic gyroscopes, fiber lasers for industrial use, scientific use and measuring purposes, single frequency fiber lasers for industrial use, scientific use and measuring purposes, optical reflectors in the nature of fiber gratings, gain flattening optical filters, scientific and technical apparatus in the nature of fiber-Bragg grating optical mirrors, electric fiber-optic coils, polarization-maintai...