31. Corneal birefringence is eliminated ( in part ) by a proprietary'corneal compensator '. 32. In 1987 Menyuk first derived the nonlinear pulse propagation equation in SMF under weak birefringence . 33. If a ray in this direction suffers no birefringence , neither will all parallel rays. 34. The birefringence of Kochite is . 0340. 35. Its birefringence value is 0.007. 36. The birefringence means the decomposition of light into two rays when passing through a mineral. 37. The absence of birefringence was initially interpreted by Brace as a refutation of length contraction. 38. The birefringence is often quantified as the maximum difference between refractive indices exhibited by the material. 39. With negative birefringence , the crystals appear yellow in parallel light and blue with perpendicular light. 40. COC materials offer exceptional transparency, low birefringence , high Abbe number and high heat resistance.
