YAG laser operating in a pulsed mode at 1.064 mm is placed in a cavity with mirrors of 98% reflectivity at each end of the laser. The scattering losses are determined to be 0.2% per pass. If the laser produces output pulses of 230 ms duration in a beam of diameter 10 mm and if the small-signal gain is measured to be 40% per pass, what would be the energy of the pulses emerging from the laser? (Use the tables given in the book to calculate needed parameters) 

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TABLE 15-5 Typical Neodymium:YAG and Neodymium:Glass Laser Parameters Laser wavelengths (ul) Laser transition probability (Aul) Upper laser level lifetime (T₂) Stimulated emission cross section (0μl) Spontaneous emission linewidth and gain bandwidth, FWHM (Avul) Inversion density (A Nul) Small-signal gain coefficient (go) Laser gain-medium length (L) Single-pass gain (eulANull) Doping density Index of refraction of gain medium Operating temperature Thermal conductivity of laser rod Thermal expansion coefficient of laser rod Pumping method Pumping bands Output power Mode Nd:YAG 1.064 μm 4.3 × 103/s 230 μs 2.8 x 10-23 m² 1.2 x 10¹¹/s (Aλul = 0.45 nm) : 1.6 x 1023/m3 5/m 0.1-0.15 m 2-20 1.4 x 1026m³ 1.82 300 K 14 W/m-K 7.7 to 8.2 x 10-6/K Nd:glass 1.054–1.062 μm 2.9 to 3.4 x 10³/s 290-340 μs 2.9 to 4.3 x 10-24 m² 1 J/pulse 7.5 x 10¹2/S (Axul = 28 nm) 8 x 1023/m³ 3/m 0.1 m 1.3 4.6 x 1026/m³ 1.50-1.57 300 K 1 W/m-K 8.5 to 14.0 x 10-6/K optical (flashlamp or laser) 300-900 nm, with strongest peaks at 810 nm and 750 nm (peaks wider in glass) up to 10 kJ/pulse in large amplifiers single-mode or multi-mode TABLE 15-5 Typical Neodymium:YAG and Neodymium:Glass Laser Parameters Laser wavelengths (ul) Laser transition probability (Aul) Upper laser level lifetime (T₂) Stimulated emission cross section (0μl) Spontaneous emission linewidth and gain bandwidth, FWHM (Avul) Inversion density (A Nul) Small-signal gain coefficient (go) Laser gain-medium length (L) Single-pass gain (eulANull) Doping density Index of refraction of gain medium Operating temperature Thermal conductivity of laser rod Thermal expansion coefficient of laser rod Pumping method Pumping bands Output power Mode Nd:YAG 1.064 μm 4.3 × 103/s 230 μs 2.8 x 10-23 m² 1.2 x 10¹¹/s (Aλul = 0.45 nm) : 1.6 x 1023/m3 5/m 0.1-0.15 m 2-20 1.4 x 1026m³ 1.82 300 K 14 W/m-K 7.7 to 8.2 x 10-6/K Nd:glass 1.054–1.062 μm 2.9 to 3.4 x 10³/s 290-340 μs 2.9 to 4.3 x 10-24 m² 1 J/pulse 7.5 x 10¹2/S (Axul = 28 nm) 8 x 1023/m³ 3/m 0.1 m 1.3 4.6 x 1026/m³ 1.50-1.57 300 K 1 W/m-K 8.5 to 14.0 x 10-6/K optical (flashlamp or laser) 300-900 nm, with strongest peaks at 810 nm and 750 nm (peaks wider in glass) up to 10 kJ/pulse in large amplifiers single-mode or multi-mode

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Answer The energy of the pulses emerging from the laser can be calculated by using the following equ... View the full answer