Littrow mount

Liquid junction potential 63, 549 Literature of analytical chemistry 6, 122, 156, 251, 253, 498, 499, 640, 641, 813, 815 Lithium, D. of as aluminate, (g) 459 Litmus 265 Litre xxix, 78 Littrow mounting 661 Logarithms four figure, 843 Lovibond comparator 655 Low voltage d.c. arc 763, 771 Lubricants for glass stopcocks 85 Lyophilic colloids 419 Lyophobic colloids 419 stability of, 419... 

Littrow mounting spect The arrangement of the grating and other components of a Littrow grating spectrograph, which is analogous to that of a Littrow quartz spectrograph. li tro, maunt-ir ... 

Most available infrared instruments use the Littrow mount for the prism, the beam being reflected from a plane mirror behind the pnsm and thus returning it through the prism a second time. This doubles the dispersion produced. Actually, a double-pass system is also used so that the beam goes through the pnsm four times. Other design modifications include those with single beam and double monochromator, double beam and double monochromator, and related combinations, See also Infrared Radiation. 

Heitmann et al. [11] designed a very compact double monochromator, consisting of a 300 mm prism pre-monochromator and a 400 mm echelle grating monochromator, both in Littrow mounting, which is shown schematically in Figure 4.3. The prism monochromator selects the part of the spectrum that is of interest, and the echelle monochromator provides the high dispersion of the selected spectral interval, which is better than 2 pm per pixel at 200 nm (see Welz et al. [10]). 

In the above Littrow mounting, internal modulation of the dispersed beam and an appropriate optical mounting allowed a second dispersion of the beam... 

The Littrow-mounted quartz prism is a 30°, 60°, 90° prism, being essentially one-half of the Cornu prism. The back surface of the prism has a reflecting surface, either silver or aluminum, such that the light is reflected through the prism as shown in Figure 3-12. The effect thus is the same as... 

Fig.3.9 Experimental setup for a line tunable liquid nitrogen cooled CO-laser. The reflection grating acts as wavelength selective end mirror and as coupling device at the same time (Littrow mount). ...

The important conclusion is that the angular dispersion of a grating depends only on the angles of incidence and diffraction. If it is arranged so that i = 0 and they are both on the same side of the normal (the Littrow mount) then... 

Consider the basic diffraction grating equation for the Littrow mount, which is most commonly used in instrumentation ... 

Fig. 4.20. (a) Littrow mount of a grating with p = a. (b) Illustration of blaze angle for a Littrow grating... 

This illustrates that the angular dispersion is determined solely by the angles a and P and not by the number of grooves For the Littrow mount with a — p, we obtain... 

Commercial instruments frequently use a so-called Littrow mount. Here a Littrow prism with a 30° angle and one surface silvered, as shown in... 

For a prism spectrometer with a Littrow mounting, the spectral slit width is s = Sg + So + ... 

Fig.4.19a,b. Illustration of blaze angle, (a) Declined incidence for commonly used grating mounts, (b) normal incidence for Littrow mount... 

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