Wedge fringe

In the wedge fringe method which is simpler, a wedge... 

Figure 3.39 Wedge fringes at an edge of aluminum foil (a) bright-field image (20,000 x magnification) and (b) schematic illustration of the wedge shape of a foil edge. (Reproduced with permission from M. von Heimandahl, Electron Microscopy of Materials, Academic Press, New York. 1980 Elsevier B. V.)...

Figure 3.44 Wedge fringe formation at a stacking fault. The face of stacking fault divides a face-centered cubic crystal into parts 1 and 2. A transmitted beam column crossing the fault is similar to that crossing a grain boundary as shown in Figure 3.39b.

Thickness Contours. The thickness dependence of /s is periodic with period I/55 the period thus diverges for j=0 (i.e., for the exact Bragg condition). The loci of equal thickness are also imaged as lines of equal intensity they are called thickness extinction contours or wedge fringes. 

Figure 1. Schematic illustration of sample geometries and THG interference fringing patterns, a). Wedge sample geometry, x is the cell displacement direction, b). Wedge THG interference fringes as a function of x. c). Slab sample geometry, 8 is the angle of incidence, d). THG interference fringes as a function of 8 (Maker Fringes).

Figure 2. Wedge THG interference fringes for solution of DPB in toluene (larger signal) and for neat toluene using 1907 nm fundamental light. The wedge cell angle was 0.26°. (Reproduced with permission from ref 27. Copyright 1989 Royal Society of Chemistry)...

Figure 3. Effect of sample absorption at 3co on wedge cell THG fringing pattern. Solid line no absorption. Dashed line weak absorption. Dot-Dash line strong absorption.

Figure 3.19. Thickness fringes in a wedge-shaped crystal of quartz oriented at the exact Bragg angle (f=0) for g=10ll. (a) Bright held, (b) Dark field.

Figure 4.14. Calculated curves showing 7o(a) and /g(a) as a function of thickness z for = 0. These curves correspond to the intensity of thickness fringes in a wedge-shaped crystal in BF and DF, respectively. Note the decrease in the fringe contrast with increasing thickness. tg/tg = 0.05 and (From Hirsch et al.

For an inclined boundary in a wedge-shaped crystal, with increasing thickness new fringes are added at the center of the fringe pattern and the outer fringes are continuous and unaffected. 

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