Matching Fluid Research Articles

Demountable multiple connector with precise V-grooved silicon

A demountable multiple connector using a precision V-grooved silicon chip has been developed. The average connection loss was 0.8 dB, including fibre end reflection. The connection losses were reduced by about 0.4 dB by using a matching fluid.

A convenient cell for angle tuned nonlinear optical crystals

The performance of a convenient cell for angle tuning of nonlinear optical crystalS, in which the crystal is rotated inside an index matching fluid, is described. Using a new fluid, the cell greatly reduces beam deviation, astigmatism, and transmission loss.

Rapid optical fiber delta measurement by refractive index tuning

A technique is presented for rapidly measuring Delta of optical fibers with profiles closely approximating n (r) = n(o) [1 - Delta(r/a)(alpha)], the Delta << 1 limit of the two-parameter Gloge-Marcatili profile. Error analysis indicates an accuracy of about +/-9%. The method is as follows: Using a Michelson interferometer together with a microscope, the transverse optical path through the center of a fiber immersed in index matching fluid is set equal to the optical path through the fluid. This is accomplished by varying the temperature of the fluid. The value of Delta can then be determined from a knowledge of the refractive index of the fluid inferred from temperature measurements. Good agreement is shown between Delta values measured by this technique and those measured by-two other interferometric techniques. The possible use of this method to determine alpha, or to determine the actual profile if it does not follow the assumed shape, is discussed.

Stress Measurement in Cylindrical Vessels

An analysis is presented of the birefringence patterns observed in the walls of cylindrical glass objects when viewed tangentially in a matching index fluid. The patterns to be expected from a combination of parabolic and bending stresses, resulting from asymmetric cooling, are calculated. Experimentally measured patterns are shown to illustrate the theory. A simple method is presented whereby the stresses at the outside and inside surfaces of tempered ware can be calculated from the observed pattern.