Minimum Optical Losses Research Articles

Low-OH-content fibre fabrication using particle-size control sol-gel method

By the sol-gel method using a new ‘particle-size control’ technique, a low-OH content at a level of 0.1 parts in 106 and a minimum optical loss of 1.8 dB/km at 1.6 μm wavelength has been achieved in pure silica core single-mode optical fibres. Improvement of dry gel properties using particle-size control is essential to bubble-free fibre drawing form dehydrated gel-derived glasses.

Fiber waveguides for the middle infrared range made of As–S and As–Se glasses with optical losses below 1 dB/m

Fiber waveguides were made from As–S and As–Se glasses. They were investigated and it was found that the minimum optical losses amounted to 0.58–0.71 dB/m in the wavelength range 3.4–4.7 μ.

Middle IR As-S and As-Se glass fibres with optical losses lower than 1 dB/m

Arsenic sulphide and arsenic selenide optical fibres have been fabricated and investigated. The minimum optical losses were 0.58–0.71 dB/m in the 3.4–4.7 μm region.

Thallium halide fiber waveguides for middle infrared range

The extrusion method was used in the fabrication of TlCl, TlBr, KRS-6, and KRS-5 fiber waveguides in which the minimum optical losses were ~3×10−3 cm−1 at wavelengths of 5–6 and 10.6 μ. Fibers 1 mm in diameter were not damaged by power densities of ~1 kW/cm2. The region of minimum material dispersion in KRS-6 and KRS-5 was found to coincide with the region of minimum optical losses.

Optimization of multimode graded-index fiber parameters: design considerations

The structural design of multimode graded-index fibers is described. Minimum optical loss and wide bandwidth of a repeater section are looked upon as design goals. The outer diameter is chosen as small as possible from an economic point of view while maintaining high quality in the transmission characteristics. The most suitably designed values for operation with a laser source in the wavelength region around 0.85 microm are o.d., 125 microm, core diam, 50 microm, and refractive-index difference, 0.015.