Grating concave

To maintain the best possible focusing for an entire concave grating of large aperture, it is therefore necessary to satisfy what at first glance seem to be two mutually exclusive conditions (4.12) ... 

Rowland grating See concave grating. ro,l3nd, grad-ir ... 

Rowland mounting spect A mounting for a concave grating spectrograph in which camera and grating are connected by a bar forming a diameter of the Rowland circle, and the two run on perpendicular tracks with the slit placed at their junction. ro,l3nd, maunt-ir ... 

William Frederick Meggers. Physicist at the U. S. Bureau of Standards since 1914. Chief of die spectroscopy section. Author of many papers on optics, astrophysics, photography, measurement of wave-length standards, and description and analysis of spectra. The instrument in the foreground is a concave grating spectrograph, used for photographing the emission spectrum of rhenium (41). 

M3, which compensates for aberrations and yields an excellent quality of image b) Czerny-Turner design, similar in conception, incorporating two spherical mirrors. M and jf/4 c) design with a concave grating (7( allowing simultaneous dispersion and focusing of the radiation. The spectral bandwidth of these monochromators depends on the width of the entrance and exit slits, F, and F2-... 

Fixed optic, concave grating instruments (spectrograph type)... 

Figure 15.5—Optical schematics of a polychromator with long focal distance and a concave grating. Reflecting mirrors can be used when lines are too close to one another. Sometimes, several polychromators are combined. To the right, principle of the Rowland circle.

The arc spectrum of niobium 1ms been measured in the region A=2600 to A=C000, using specimens of the pentoxide obtained from several niobium ores and a concave grating of 6 feet focus.2 The more intense lines are tabulated in the following table —... 

Many modern spectroscopes employ the diffraction grating instead of the prism. In the concave grating spectroscope, developed by Rowland, the collimating lens and telescope or camera objective are unnecessary because of the focusing effect of the grating itself. See Fig, 2,... 

Fig. 2. Concave grating spectroscope Slit, S grating, G, eyepiece or plate-holder, E...

Figure 1. Schematic diagram of the apparatus. The laser system which produces a 1.06 pm ultra-short pulse and its 353 nm third harmonic is not shown. F denotes filter L, lens CC, continuum generation cell D, diffusing plate CL, cylindrical lens S, spectrograph slit G, concave grating FP, focal plane DC, detector controller. 10 and 1 label the continuum beams passing through...

Fig. 19. Important optical mountings for optical spectrometers with a plane (A Ebert, B Czerny-Turner) and a concave (C Seya-Namioka, D Paschen-Runge) grating, m Mirror, se entrance slit, sa exit slit, gp plane grating, gc concave grating.

Mountings with a concave grating are also used. Here the radius of the grating determines the so-called Rowland circle. In the direction of dispersion the spectral lines are focussed on the Rowland circle and are monochromatic images of the... 

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