Partially reflecting mirrors

The mode-locked laser output is split into two parts by use of a partially-reflecting mirror or beam splitter. The two pulses leave the... 

Figure 7.12 Outline of a pulsed solid-state laser. L, flash lamp for pump light C, high-voltage capacitor T, trigger spark gap Mr, reflecting mirror Ms, partially reflecting mirror R, rod of lasing material Q, Qjswitch cell or crystal...

The active material in a dye laser is a liquid solution of a dye in a solvent. The fluorescence of the dye is excited by a pump light, which can be a flash of white light (seldom used nowadays) or a UV laser pulse from an Nd/YAG or exciplex laser. Figure 7.19 shows the principle of such a dye laser. The cavity consists of a diffraction grating, G, which plays the role of a totally reflecting mirror, and of a partially reflecting mirror which will let the laser... 

The Bragg law can also be derived in a simple manner. Suppose a plane wave is incident upon a crystal at a grazing angle 0 to a set of atomic planes hkl) which behave like partially reflecting mirrors spaced a distance d(hkl) apart, as shown in Figure 3.4. It is clear that the path difference between the two waves shown is 2d(hkl) smO. Constructive interference between waves reflected from successive planes occurs when this path difference is an integral number of wavelengths. Thus,... 

Perhaps the simplest (but not the first) example of this approach is a direct descendant of the 180° geometry used in microscopes (Fig. 6.3). A partially reflective mirror or dichroic mirror combines the excitation and collection axes, as shown in Figure 12.18 for a probe built by DLT, Inc. This mirror is commonly referred to as a beamsplitter, even though its function is... 

FIGURE 22.24 (a) In this solid-state laser, photons emitted as electrons and holes recombine to stimulate the emission of additional photons, (b) Reflection by a mirror on the right side sends coherent waves back through the laser medium, (c) Further amplification occurs by stimulated emission, (d) Some of the waves pass through a partially reflecting mirror on the left side. 

We are going to consider a particular type of laser known as a solid-state laser, which consists of a collection of special laser-active atoms embedded in a solid-state matrix, bounded by partially reflecting mirrors at either end. An external energy source is used to excite or pump the atoms out of their ground states (Figure 3.3.1). 

A Fabry-Perot interferometer is formed by an adjustable optical cavity between two partially reflecting mirrors, as shown schematically in... 

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