Working distance

The standard 40x objective is the 0.65-NA version, rather than the higher resolution but shorter working distance 0.85-NA objective. 

The beam next arrives at the final lens-aperture combination. The final lens does the ultimate focusing of the beam onto the surface of the sample. The sample is attached to a specimen stage that provides x- and j>-motion, as well as tilt with respect to the beam axis and rotation about an axis normal to the specimen s surface. A final z motion allows for adjustment of the distance between the final lens and the sample s surface. This distance is called the working distance. 

Obhut, /. protection, care, obig, a. above, above-mentioned, foregoing. Objekt-abstand, m. (Micros.) working distance, -glas, n. (Micros.) slide, mount, -halter, m. (Micros.) specimen holder. 

Identification and maintenance of safe working distances between sources and employees ... 

An industrial microscope with a long-working distance 20 X objective is used for the collection of the chromatic interference patterns. They are produced by the recombination of the light beams reflected at both the glass/chromium layer and lubricant/steel ball interfaces. The contact is illuminated through the objective using an episcopic microscope illuminator with a fiber optic light source. The secondary beam splitter inserted between the microscope illuminator and an eyepiece tube enables the simultaneous use of a color video camera and a fiber optic spectrometer. 

Processing in the micro reactor was analyzed by a CCD camera with a long working distance magnifying lens [22]. Visible spectrometry was applied for in-line sensing. The change in product concentration was determined at 450 nm. The light was collected via an optical fiber and sent to the spectrometer. 

Citing their successes, many chemists tended to emphasize the empirical and descriptive characteristics of their work, distancing themselves from spec-... 

Milling time that is closely related to milling mode, working distance, and type of process. Ball milling requires usually shorter time than mechanical alloying or reactive ball milling... 

Fig. 1.9 The attractive force between the 25-mm steel ball metal vs. distance from the cylinder (working distance - WD) and four various magnets...

FIGURE 8.5 Effect of dispersion compensation in two-photon depth imaging. Image acquisition of thick mouse kidney sample collected in a series of z-sections at different depths, which demonstrates that MIIPS compensated pulses attain better signal, and deeper penetration than those with GDD-only compensation. The image size is about 100 pm. The objective used is Nikon 60 x 1.45 NA, with working distance of 130 pm. (From Xi et al. Opt. Comm. 281(7) 1841-1849, 2008. Used with permission.)... 

Long work / distance /Sample surtace Focused spot l objective ... 

AFM is further complicated by the deformation of the tip and sample near the gap region (Teague, 1978 Coombs and Pethica, 1985 Chen and Hamers, 1991a). At very short tip-sample distances, the reading from the z piezo no more represents the gap displacement. Nevertheless, in the normal working distance range of STM, the dominant force is the resonance force, and the simple relation is valid. 

Photomicrographs of each material were taken with a Jeol JSM-5800 scanning electron microscope (SEM) (Jeol USA Inc., Peabody, Massachusetts, U.S.A.). The photographs were taken at a working distance of 10 mm, with an accelerating voltage of 5 to 10 kV. 

Unfortunately, the working distance for commercial stereo microscopes is rather short, and the microscope also does not accommodate readily the usual large glove box with a vertical or slightly inclined window. A single-chamber evacu-able dry box is available commercially which would appear to be satisfactory for crystal mounting and other operations in which the apparatus is not large.2... 

Working Distance 6-40 mm 6-15 mm, resolution limited by beam scattering in gas... 

The short working distance, high NA sampling configuration is ideal for measuring liquids or powders, where the presentation of the sample to the probe is fixed and consistent. However, it fails for solid samples that cannot be brought close to the probe, have uneven surfaces, or whose position cannot be controlled accurately. It should be noted that many of the biomedical and pharmaceutical applications in this book would fall into this category. 

A typical fibre probe will illuminate the sample with a laser spot whose dimensions are dependent on the launch optics and the position of the sample relative to the probe end. For a static sample, the volume interrogated will depend on the Raman scattering properties, working distance and the acceptance angle of the fibre collection optics. For a sample moving in the laser beam, the sampled volume is also dependent on the time taken for signal averaging and the velocity of the sample. 

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