Optical fiber waveguides with a large-diameter core and low optical losses

A description is given of the technology for making optical fiber waveguides with a quartz-glass core of diameter ~400 μ and polymer cladding. The latter was deposited directly during the drawing of the fiber using heat from a CO₂ laser or an oxygen-hydrogen torch. The minimum losses in a waveguide with an excitation aperture of 0.2 were 18 dBAm at 0.8 μ wavelength.