A loss-spectrum measuring-system for hollow waveguides was established based on the Fourier Transform infrared Spectrometer (FTIR). In order to obtain better repeatability, we designed and fabricated two couplers for the system. One is a silver-coated hollow tube with the same inner diameter as the measured hollow waveguide. The other is a silver-coated tapered coupler whose inner diameter of the output end is the same as the measured hollow waveguide. Characteristics of the measuring system were discussed theoretically and experimentally when using the two couplers. Several kinds of hollow waveguides were measured and the properties of the loss spectra were discussed. The measured loss property showed that loss property depends on the output divergence angle of the coupler. Tapered coupler has a much larger output divergence than that of the hollow tube. Both of the couplers attains stable coupling with the hollow waveguides. Loss spectra were successfully measured for hollow waveguides with the length ranging from several centimeters to 3 meters.
[1]
Daniel Poitras,et al.
Toward perfect antireflection coatings. 2. Theory.
,
2004,
Applied optics.
[2]
Penghui Ma,et al.
Toward perfect antireflection coatings. 3. Experimental results obtained with the use of Reststrahlen materials.
,
2006,
Applied optics.
[3]
M. Mohebbi.
Transmission characteristics of femtosecond optical pulses in hollow-core fibers
,
2005
.
[4]
J A Harrington,et al.
Attenuation, modal, and polarization properties of n < 1, hollow dielectric waveguides.
,
1993,
Applied optics.
[5]
Mitsunobu Miyagi,et al.
Loss characteristics of circular hollow waveguides for incoherent infrared light
,
1989
.
[6]
M Miyagi,et al.
Cyclic olefin polymer-coated silver hollow glass waveguides for the infrared.
,
1998,
Applied optics.
[7]
James A. Harrington,et al.
A Review of IR Transmitting, Hollow Waveguides
,
2000
.
[8]
E. Palik.
Handbook of Optical Constants of Solids
,
1997
.