Using this method, the birefringence
of Samples 1 through 5 was measured at either +0.028 or +0.030.
So far, birefringence
hasn't been a problem for the all-glass optics in current steppers.
In patients with chronic or resolving arthritis, the leukocyte count is below 2 x [10.sup.3] cells/[micro]L (2000 cells/[mm.sup.3]), with a predominance of mononuclear cells often with intracellular and extracellular crystals. Histologically, pseudogout presents with nodular deposits of CPPD crystals.[4-7] Hematoxylin-eosin-stained sections may not show significant numbers of polarizable crystals owing to the masking of these crystals by hematoxylin in H&E-stained sections (Figure 2, C); however, when the sections are stained with the Shidham method,[1,8,9] all the crystals polarize (Figure 2, G) with diagnostic weak positive birefringence
(Figure 2, D and H).
In this paper, we primarily focus on the kinetics of structural evolution as reflected in real-time birefringence
measurements during constrained annealing of films that underwent simultaneous as well as sequential biaxial stretching.
The Pol-Scope reveals the birefringence
retardation, also called retardance, of astral microtubules irrespective of their orientation within the plane of focus.
Ordinarily, a crystal with a cubic structure such as calcium fluoride does not exhibit birefringence
in stress-free material because of its high symmetry.
Changes in the chain orientation as caused by the internal hollows formation are characterized by birefringence
from the refractive indices parallel and perpendicular to the fiber axis.
Described as "crystal clear," the new polycarbonate (PC) film is said to be an excellent substrate material for data-storage layers, exhibiting low birefringence
and high heat deflection temperatures under load.
We reported earlier on a centrifuge polarizing microscope (CPM) that was designed for observing the weak birefringence
of organelles and fine structures in living cells as they became stratified and oriented under centrifugal fields of up to 10,500 times Earth's gravitational field.
The practical import for designers is that a calcium fluoride lens will not focus properly without, at the very least, careful control of the light as it enters the lens and a design that accounts for this intrinsic birefringence
. This is a difficult problem given that there are about 20 such lens elements in a typical stepper or optical lithography lens.