Prisms dispersion

Figure B2.1.1 Femtosecond light source based on an amplified titanium-sapphire laser and an optical parametric amplifier. Symbols used P, Brewster dispersing prism X, titanium-sapphire crystal OC, output coupler B, acousto-optic pulse selector (Bragg cell) FR, Faraday rotator and polarizer assembly DG, diffraction grating BBO, p-barium borate nonlinear crystal.

M, dichroic mirror P, dispersive prism I, iris L, lens T, 5-axis fiber positioner PUT 1, detection photomultiplier tube ... 

Figure 3.6-8 Experimental set-up for CARS spectroscopy in the condensed phase. A = aperture AL = achromatic lens BS = beam. splitter CL = calibration lamp D = diffuser Dl, D2 = diodes FR = double Fresnel rhombus L = lens M = mirror P = Glan-Thompson polarizer PA = preamplifier PHS = Prism Harmonic Separator PM = photomultiplier PR = linear dispersing prism arrangement S = shutter (Materny et al., 1992a).

Figure 1.1 Simple diagram showing separation of combined multiple wavelengths using a light dispersion prism...

Detection of emission for qualitative analysis usually employs a photographic plate (13,14). The emission passes through a dispersive prism or grating, and impinges on the plate. The entire spectrum of the sample is thus displayed with one measurement, providing a permanent record of the results. Since the... 

Commercial laser scanning microscopes use the same microscope body and the same scan optics for one-photon and two-photon excitation. Most two-photon microscopes have lasers for one-photon excitation as well. They can switch between both modes, and between descanned and nondescanned detection. Moreover, in both the descanned and the nondescanned detection path, the light is split spectrally by additional dichroic mirrors or dispersion prisms and several detectors are used to record images in selectable wavelength ranges. The dichroic mirrors and filters are assembled on motor-driven wheels and are changed on command. The laser power... 

Since prism beam expanders and subsequently multiple-prism arrays have become rather important in many areas of optics, it is appropriate to consider them in some detail and to mention a few relevant historical aspects. The prism as a beam expander was first depicted by Newton, in his book Opticks, in 1704. He also considered prism arrays to control dispersion. Prism pairs applied to beam expansion were introduced by Brewster, in 1813. The prism was first used as a beam expander in a dye laser by Myers in 1971 and by Stokes et al in 1972. Beam expanders comprised of prism pairs and several prisms were introduced independently to tunable lasers by Kasuya et al and Klauminzer in the late 1970s. 

Figure 10.8 Dispersing prism. Top concept of beam deviation in a prism with hypotenuses angle a all other relevant angles are indicated (for details see text). Bottom chromatic dispersion by a prism...

For an equilateral (dispersive) prism, the wave propagation angle (S) (shown in Fig. 6) through the prism is given by... 

The conventional spectrometer with a dispersive prism or grating has been largely superseded by the Fourier transform (FTIR) technique. This uses a moving mirror in an interferometer to produce an optical transform of the infrared signal. Numerical Fourier analysis gives the relation of intensity and frequency, that is, the IR spectrum. FTIR can be used to analyze gases, liquids and solids with minimal preparation in short times. FTIR has been applied to the study of many systems, including adsorption on polymer surfaces, chemical modification and irradiation of polymers and oxidation of rubbers [36]. The application of infrared spectroscopy to the study of polymers has been reviewed by Bower and Maddams [35]. 

The Pellin-Broca prism also deviates beams by roughly 90° but is a dispersive prism, frequently used to separate laser beams of different colours after nonlinear frequency conversion (Sect. 8.6). By combining four Pellin-Broca prisms, beam separation with maintained direction of propagation can be achieved. In the straight-view prism colour d persion in the forward... 

The mirror dispersion can be compensated by inserting into the ring resonator (Fig. 11.18) dispersive prisms which introduce different optical path lengths dpn(A) [11.49a]. This dispersion compensation can be optimized by... 

The principle of the dispersive prism or diffractive grating spectrometer can be readily extended to the infrared and even to the far infrared. However the photographic plate for the recording and measurement of the spectrum is not available here. Early devices for sensing infrared radiation consisted of sensitive thermometric devices called bolometers. Bolometers do not form images and hence a spectrum must be recorded by sequentially displacing the bolometer to measure the intensity of radiation at different wavelengths. 

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