Differential interference

Fig. 2. Differential interference contrast (Nomarski) microscope, showing exaggerated light path (12).

In video microscopy, for instance, background is normally subtracted using differential interference contrast (DIC) [18]. This technique, which requires a number of manipulations from the user, may now be automated using a new method called polarization-modulated (PMDIC) [19,20], It requires the introduction of a liquid crystal electro-optic modulator and of a software module to handle difference images. PMDIC has been shown to bring improvements in imaging moving cells, which show a low contrast, as well as thick tissue samples. 

FIGURE 2-11 Video-enhanced Differential Interference Contrast (DIC) images of gold-labeled p opioid GPCR on the surface of a GPCR-transfected fibroblast. The white trace is the trajectory of one particle over 2 minutes at 25frames/s. The black trace is the mean square displacement of the particle as a function of time. Reproduced from Figure 1 of [30], with permission. 

Contrast. See also Differential interference contrast (DIC) computer-assisted, 16 487 in microscopy, 16 474 techniques for improving, 16 474-487... 

Differential centrifugation, 5 531 Differential contacting, 10 760-762 Differential display, 13 354 Differential equations, 11 736 of motion, 11 738-739 Differential interference contrast (DIC), 16 480-483... 

Reflected light differential interference contrast (DIC), 16 482 Reflection correction algorithms, 24 456 Reflection high-energy electron diffraction (RHEED), 24 74 Reflection indexing... 

Li, J. H., Guiltinan, M. J., and Thompson, D. B. 2006. The use of laser differential interference contrast microscopy for the characterization of starch granule ring structure. Starch-Starke 58 1-5. 

Later, differential interference microscopy was developed, enabling the detection of difference in levels as sensitively as phase contrast microscopy, and, because this technique was easier to use, it came to be used in preference to the former techniques [6]. Differential interference microscopy is superior to phase contrast microscopy in the observation of vicinal or curved surfaces, which are impossible to observe under a phase contrast microscope because the contrast is too high. 

Optical microscopy, such as phase contrast or differential interference contrast. 

Powerful methods that have been developed more recently, and are currently used to observe surface micro topographs of crystal faces, include scanning tunnel microscopy (STM), atomic force microscopy (AFM), and phase shifting microscopy (PSM). Both STM and AFM use microscopes that (i) are able to detect and measure the differences in levels of nanometer order (ii) can increase two-dimensional magnification, and (iii) will increase the detection of the horizontal limit beyond that achievable with phase contrast or differential interference contrast microscopy. The presence of two-dimensional nuclei on terraced surfaces between steps, which were not observable under optical microscopes, has been successfully detected by these methods [8], [9]. In situ observation of the movement of steps of nanometer order in height is also made possible by these techniques. However, it is possible to observe step movement in situ, and to measure the surface driving force using optical microscopy. The latter measurement is not possible by STM and AFM. 

Figure 5.6. Differential interference contrast photomicrographs showing the morphology of growth spirals observed on (a) (0001), (b) (2131), and (c) (1010) faces of synthetic emerald.

Figure 5.8. (a) Typical spiral pattern (phase contrast photomicrograph of (0001) face of Sic grown from the vapor phase), and spiral growth hillocks which appear as (b) polygonal and (c) conical pyramids due to narrow step separation. Part (b) is a differential interference photomicrograph, (1010), and part (c) is a reflection photomicrograph, (1011), of hydrothermally synthesized quartz. 

Figure 12.1. Elemental spiral step patterns observed on the 0001 face of beryl, (a) Low magnification, reflection (b) high magnification, differential interference contrast photomicrograph.

Figure 7.22 Microstructure of acidified mixed emulsions (20 vol% oil, 0.5 wt% sodium caseinate) containing different concentrations of dextran sulfate (DS). Samples were prepared at pH = 6 in 20 mM imidazole buffer and acidified to pH = 2 by addition of HCl. Emulsions were diluted 1 10 in 20 mM imidazole buffer before visualization by differential interference contrast microscopy (A) no added DS (B) 0.1 wt% DS (C) 0.5 wt% DS (D) 1 wt% DS. Particle-size distributions of the diluted emulsions determined by light-scattering (Mastersizer) are superimposed on the micrographs, with horizontal axial labels indicating the particle diameter (in pm). Reproduced with permission from Jourdain et al. (2008).

KETENES, KETENE DITffiRS AND RELATED SUBSTANCES] (Vol 14) DIC. See Differential interference contrast. 

Fig. 4.3.14. Plexiglass, differential interference contrast, grey of 1st order, Vickers indenter, load 122.5 mN, filter 546 mm, measurement magnification 260 x, photograph enlargement 400 x. (After OPTON Feintechnik, Oberkochen)...

For optical microscopic examination, a Zeiss Axioplan microscope and brightfield (BF), darkfield (DF), polarized light (P) and differential interference... 

Figure 10. Photomicrograph of the differential interference pattern of a pseudoemulsion film (octane drop in 4 wt% C1215AE30 solution).

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