Effective magnification

A Leitz Ortholux microscope was used to determine the maceral content of Rasa coal. The microscope was fitted with an oil- immersion 60X fluoride objective and 10X high eyepoint oculars to give an effective magnification of 720 diameters. A point count system of analysis was used for the maceral determination. 

The resolution of the human eye is around 0.3 mm, therefore the maximum effective magnification with white light is ... 

A higher magnification than the effective magnification only makes the image bigger, may make eyes more comfortable during observation, but does not provide more detail in an image. 

Estimate the effective magnifications of an SEM image showing on your computer screen when the probe size varies between 1 nm and 1 gm. 

Closed-circuit television (CCTV) systems magnify print and small objects up to 60 times, with higher effective magnifications possible by close viewing. Users with vision as poor as 1/400 (20/8000) may be able to read ordinary print with CCTV [Fonda, 1981]. Some recent units are portable and contain black/white image reversal and contrast enhancement features. 

White light interferometry was employed to inspect the stamps and replicates used in this research in device fabrication. The Wyko NT3300 surface profiler is a commercially available inspection system equipped with hardware and software for data acquisition and analysis (www.veeco.com). The metrology system has 0.1 nm resolution in the vertical (z) axis. Laterally, in the XY plane, resolution is dependent on the pixel size in each scan. Thus, the objective and field of view of the scan determines lateral resolution. Scans in this study were performed using 20.8x effective magnification, translating to 0.7 pm pixel size. Considering the size scale of the structures involved, this lateral resolution was... 

There have been several basic technical issues regarding quality assurance for high-density flex circuits, as listed in Table 67.1. Because of the fine circuits and the severe acceptable level of the defects, low-magnification scopes and low-resolution AOI do not work effectively. Magnification of 20 X to 50 X is required for visual inspections of fine circuits, and higher resolutions are required for AOI systems. Low contrast between copper and polyimide base creates another difficulty for traditional AOI equipment. It is not easy for common AOI systems to distinguish the copper traces from the circuits on the other side of a double-sided circuit built on adhesiveless substrate, because the base layer is very transparent and the sensor detects both sides of the circuits as one. 

Fig.4 Geometrical magnification effect inherent to the tangential exposure technique...

When a eutectoid steel is slowly cooled from the austenite range, the ferrite and cementite form in alternate layers of microscopic thickness. Under the microscope at low magnification, the diffraction effects from this mixture of ferrite and cementite give an appearance similar to that of a pearl, hence the material is called peadite. 

Requirements of Standards. Standards used In the calibration of mlcrospectrofluorometrlc Instrumentation must meet more stringent requirements than those used In macromeasurements. The effect of Increased excitation flux as well as spatial effects under magnification make many macromeasurement standards unsatisfactory for micromeasurements. Following are some of the requirements for fluorescence standards that are strongly Influenced by a change from the macro- to the micro-environment. 

The accuracy of any expression for first order errors can be improved as much as desired (so long as the expression is differentiable) by including additional terms of its Taylor expansion. For example, the error magnification factor in the age equation for the 230Th/238u term, (p, can be improved to include the second derivative, so the estimate of the effect of a given error in cp on the age becomes ... 

The mapping conditions were chosen by the authors to minimize the frame time and to maximize the counting statistics by increasing the probe size and probe current, while reducing the number of pixels in the map. These authors summarized the effect of the low-magnification mapping parameters on the measured analytical resolution for their specimen/microscope combination in Table 5.1. 

Figure 5. The effect of ultrasonic irradiation on particle aggregation as shown by scanning electron micrographs of Ni powder (at 10 X less magnification than Figure 4).

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