Apochromats

Most glasses have dispersions which follow a standard relation with change of wavelength. Some glasses have anomalous dispersion, and these are useful for the design of highly colour-corrcctcd lens sets, so-called apochromatic objectives. 

Apochinin, n. apoquinine. apochromatisch, a. apochromatic. Apogluzinsdure, /. apoglucic acid. Apohydrochinin, n. apohydroquinine. Apokaffein, n. apocaffeine. 

Using three lenses, exceptionally two with favourable glasses, it is possible to superimpose the foci at three wavelengths. Such systems are called apochromats... 

Apochromatic objectives, 16 471 Apocynaceae, alkaloids in, 2 75 Apodization process, 14 227 apo E gene, and LDL level, 5 136 Apoglucose oxidase (apo-GOD), 14 148 Apolipoprotein B deficiencies, 17 652 Apparel, nylon, 19 766 Apparent bypass... 

Apochromat Microscope objective that has better color correction than the much more common achromat objectives corrected chromatically for two wavelengths of light (red and blue). Apochromatic objectives are corrected chromatically for three colors (red, green and blue) and spherically for two colors, which practically eliminates chromatic aberration. 

Neofluar objectives are chromatically better corrected than the achromatic objectives (fluorite), but worse than the plan-apochromat objectives. The contrast of the neofluar objectives is however larger than with the plan-apochromat objectives. 

Fig. 5. Optical sectioning of rhodamine phalloidin-stained F-actin in a neutrophil migrating through a 5-pm pore of a polycarbonate membrane. The neutrophil migration is stimulated in response to 10 M Af-formytmethionyl-leucy 1-phenylalanine. (A), (B), and (C) correspond to O.S-pm optical sections indicated as sections A, B, and C, respectively, in Fig. 4. The bar represents 10 pm. The images were collected with a Nikon Microphot FX microscope (x60 Plan-apochromat lens, numerical aperture, 1.6) connected to a Bio-Rad MRC600 laser-scanning confocal system.

Analyze the distribution of fluorescence in live unfixed cells on a Zeiss Axiovert 200 M fluorescence microscope with 63 x Plan-Apochromat objective, an Axio-Cam MRm camera, and Axiovision software. 

These aberrations can be corrected by coatings and proper lens design, but the corrections increase the cost of the lens, thus lens designers offer lenses with different degrees of correction and consequently cost. The most common corrections are achro-mats, semi-apochromats and aprochromats. Table 10 gives examples of the different types of corrections done for commercially available lenses. 

Estimate the bacteria from the mounted sample but allow the sample to stand not less than 15 minutes after mounting, before counting. Employ a magnification of about 500r which may be obtained by the use of an 8 mm. Zeiss apochromatic objective with an X18 Zeiss... 

Perform the experiments with a 60x/1.45 Plan-Apochromat oil objective. 

Apo (apochromatic) Corrected for red, green, and blue spectra. This allows higher numerical apertures (NA) to be achieved, optimizing resolution and color transmission for photomicrography. 

Plan Apo (plan apochromatic) Corrected for spherical aberration and spectral continuity. These objectives may contain up to 15 separate lenses, as reflected in their price. For black-and-white photography and under the correct lighting conditions, a Plan lens may equal a Plan Apo lens in resolution. However, for color photomicrographs, the latter is preferred. 

Apochromat a-p9-kro- mat [ISV] (1887) adj. A term applied to photographic and microscope objectives indicating the highest degree of color correction. 

Apochromatic objective n. An objective corrected for spherical aberration at two wavelengths and for chromatic aberration at three wavelengths. 

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