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• 11. [Article] Threshold characteristics of mirrorless lasers

  Detailed analytical expressions are developed for the output power and spectral characteristics of high‐gain mirrorless laser amplifiers. With regard to intensity variations and spectral narrowing, such ...

  Citation × Citation Citation Abstract Copy Title: Threshold characteristics of mirrorless lasers Author: Casperson, Lee W. Year: 1977 Detailed analytical expressions are developed for the output power and spectral characteristics of high‐gain mirrorless laser amplifiers. With regard to intensity variations and spectral narrowing, such lasers are similar in behavior to conventional laser oscillators. A threshold transition region is apparent as saturation sets in, and spectral rebroadening occurs in inhomogeneously broadened laser systems. These solutions take full account of saturation by both the right and left propagating radiation, and the results agree with experiments that have been reported. Title: Threshold characteristics of mirrorless lasers Author: Casperson, Lee W. Year: 1977 Detailed analytical expressions are developed for the output power and spectral characteristics of high‐gain mirrorless laser amplifiers. With regard to intensity variations and spectral narrowing, such lasers are similar in behavior to conventional laser oscillators. A threshold transition region is apparent as saturation sets in, and spectral rebroadening occurs in inhomogeneously broadened laser systems. These solutions take full account of saturation by both the right and left propagating radiation, and the results agree with experiments that have been reported. Close

• 12. [Article] Properties of a coaxial cw CO₂ laser

  A cw CO₂ laser has been developed in which the active medium is formed by a discharge between coaxial electrodes. The laser gain and saturation properties have been studied as functions of the various ...

  Citation × Citation Citation Abstract Copy Title: Properties of a coaxial cw CO₂ laser Author: Ken, T.-K. Cheng, Casperson, Lee W. Year: 1979 A cw CO₂ laser has been developed in which the active medium is formed by a discharge between coaxial electrodes. The laser gain and saturation properties have been studied as functions of the various device parameters. Over-all efficiency is about the same as for a conventional longitudinal discharge laser, and advantages of the coaxial geometry include low voltage operation, rapid cooling, and rugged construction. Title: Properties of a coaxial cw CO₂ laser Author: Ken, T.-K. Cheng, Casperson, Lee W. Year: 1979 A cw CO₂ laser has been developed in which the active medium is formed by a discharge between coaxial electrodes. The laser gain and saturation properties have been studied as functions of the various device parameters. Over-all efficiency is about the same as for a conventional longitudinal discharge laser, and advantages of the coaxial geometry include low voltage operation, rapid cooling, and rugged construction. Close

• 13. [Article] Rate-Equation Approximations in High-Gain Lasers

  The rate-equation approximation is one of the most fundamental and universally employed simplifications in laser analyses. The accuracy and regions of applicability of this approximation are explored in ...

  Citation × Citation Citation Abstract Copy Title: Rate-Equation Approximations in High-Gain Lasers Author: Casperson, Lee W. Year: 1997 The rate-equation approximation is one of the most fundamental and universally employed simplifications in laser analyses. The accuracy and regions of applicability of this approximation are explored in comparisons with more rigorous semiclassical models. Higher-order rate-equation approximations are also developed, and these improved models can yield much better accuracy than conventional rate equations with little added complexity. The modified adiabatic elimination methods reported here would also be useful in reducing the mathematical models governing other physical systems. Title: Rate-Equation Approximations in High-Gain Lasers Author: Casperson, Lee W. Year: 1997 The rate-equation approximation is one of the most fundamental and universally employed simplifications in laser analyses. The accuracy and regions of applicability of this approximation are explored in comparisons with more rigorous semiclassical models. Higher-order rate-equation approximations are also developed, and these improved models can yield much better accuracy than conventional rate equations with little added complexity. The modified adiabatic elimination methods reported here would also be useful in reducing the mathematical models governing other physical systems. Close

• 14. [Article] Coherence effects in synchronously pumped mode‐locked dye lasers

  A formalism is developed for describing the evolution of picosecond mode‐locked pulses in synchronously pumped dye lasers. The finite phase memory of the molecular wave functions is included, and it is ...

  Citation × Citation Citation Abstract Copy Title: Coherence effects in synchronously pumped mode‐locked dye lasers Author: Casperson, Lee W. Year: 1982 A formalism is developed for describing the evolution of picosecond mode‐locked pulses in synchronously pumped dye lasers. The finite phase memory of the molecular wave functions is included, and it is found that the resultant coherence effects can be dominant for operation close to exact synchrony. Considerations of the isotropic molecular orientational distribution and the finite vibrational relaxation times are also essential in obtaining quantitative agreement with experimental results. Title: Coherence effects in synchronously pumped mode‐locked dye lasers Author: Casperson, Lee W. Year: 1982 A formalism is developed for describing the evolution of picosecond mode‐locked pulses in synchronously pumped dye lasers. The finite phase memory of the molecular wave functions is included, and it is found that the resultant coherence effects can be dominant for operation close to exact synchrony. Considerations of the isotropic molecular orientational distribution and the finite vibrational relaxation times are also essential in obtaining quantitative agreement with experimental results. Close

• 15. [Article] Pump polarization effects in cw dye lasers

  The effects of pump polarization on the performance of cw dye lasers have been investigated. A recently developed semiclassical model for synchronously pumped mode‐locked dye lasers is adapted to the problem ...

  Citation × Citation Citation Abstract Copy Title: Pump polarization effects in cw dye lasers Author: Casperson, Lee W., Sandle, W. J., Wilson, A. C., Warrington, D. M., Ballagh, R. J. Year: 1991 The effects of pump polarization on the performance of cw dye lasers have been investigated. A recently developed semiclassical model for synchronously pumped mode‐locked dye lasers is adapted to the problem of cw dye‐laser oscillation, and analytic expressions are obtained for the relationship between the pump power, pump polarization, and dye‐laser output power. The theoretical results are compared with experimental data obtained using an argon‐laser‐pumped rhodamine 6G dye laser. Title: Pump polarization effects in cw dye lasers Author: Casperson, Lee W., Sandle, W. J., Wilson, A. C., Warrington, D. M., Ballagh, R. J. Year: 1991 The effects of pump polarization on the performance of cw dye lasers have been investigated. A recently developed semiclassical model for synchronously pumped mode‐locked dye lasers is adapted to the problem of cw dye‐laser oscillation, and analytic expressions are obtained for the relationship between the pump power, pump polarization, and dye‐laser output power. The theoretical results are compared with experimental data obtained using an argon‐laser‐pumped rhodamine 6G dye laser. Close

• 16. [Article] Light extinction in polydisperse particulate systems

  Analytic methods are developed for determining the attenuation characteristics of light beams propagating through ensembles of scattering particles including those with complex index of refraction. The ...

  Citation × Citation Citation Abstract Copy Title: Light extinction in polydisperse particulate systems Author: Casperson, Lee W. Year: 1977 Analytic methods are developed for determining the attenuation characteristics of light beams propagating through ensembles of scattering particles including those with complex index of refraction. The methods are applicable to a wide range of practical particulate systems, and the results are expressed explicitly in terms of elementary functions. Propagation through fog and clouds is considered as an example, and it is found that absorption by the liquid lengths. water in such ensembles affects strongly the extinction for ir wave-lengths Title: Light extinction in polydisperse particulate systems Author: Casperson, Lee W. Year: 1977 Analytic methods are developed for determining the attenuation characteristics of light beams propagating through ensembles of scattering particles including those with complex index of refraction. The methods are applicable to a wide range of practical particulate systems, and the results are expressed explicitly in terms of elementary functions. Propagation through fog and clouds is considered as an example, and it is found that absorption by the liquid lengths. water in such ensembles affects strongly the extinction for ir wave-lengths Close

• 17. [Article] Generalized Beam Matrices. III. Application to Diffraction Analysis

  In analogy with Huygen’s wavelets a new method based on Gaussian beamlets is used to develop a conventional diffraction integral formalism for paraxial optical systems representable by complex 2×2 ABCD ...

  Citation × Citation Citation Abstract Copy Title: Generalized Beam Matrices. III. Application to Diffraction Analysis Author: Casperson, Lee W., Tovar, Anthony A. Year: 1996 In analogy with Huygen’s wavelets a new method based on Gaussian beamlets is used to develop a conventional diffraction integral formalism for paraxial optical systems representable by complex 2×2 ABCD Gaussian beam matrices. This method, along with a new phase parameter transformation, is then used to produce a new diffraction integral for studying the propagation of light beams with arbitrary spatial profiles through much more general misaligned complex optical systems representable by 3×3 ABCDGH beam matrices. Title: Generalized Beam Matrices. III. Application to Diffraction Analysis Author: Casperson, Lee W., Tovar, Anthony A. Year: 1996 In analogy with Huygen’s wavelets a new method based on Gaussian beamlets is used to develop a conventional diffraction integral formalism for paraxial optical systems representable by complex 2×2 ABCD Gaussian beam matrices. This method, along with a new phase parameter transformation, is then used to produce a new diffraction integral for studying the propagation of light beams with arbitrary spatial profiles through much more general misaligned complex optical systems representable by 3×3 ABCDGH beam matrices. Close

• 18. [Article] Generalized Beam Matrices. II. Mode Selection in Lasers and Periodic Misaligned Complex Optical Systems

  A generalized beam matrix method is used to investigate the mode structure of astigmatic misaligned optical systems with loss or gain. In these optical systems the usual real-argument polynomial-Gaussian ...

  Citation × Citation Citation Abstract Copy Title: Generalized Beam Matrices. II. Mode Selection in Lasers and Periodic Misaligned Complex Optical Systems Author: Casperson, Lee W., Tovar, Anthony A. Year: 1996 A generalized beam matrix method is used to investigate the mode structure of astigmatic misaligned optical systems with loss or gain. In these optical systems the usual real-argument polynomial-Gaussian beams are not eigenfunctions, and off-axis complex-argument polynomial beams must be used. New beam transformations for these complex-argument modes are reported. Stability criteria are developed, and mode selection in laser resonators that contain tilted, displaced, or curved complex optical elements is discussed. Title: Generalized Beam Matrices. II. Mode Selection in Lasers and Periodic Misaligned Complex Optical Systems Author: Casperson, Lee W., Tovar, Anthony A. Year: 1996 A generalized beam matrix method is used to investigate the mode structure of astigmatic misaligned optical systems with loss or gain. In these optical systems the usual real-argument polynomial-Gaussian beams are not eigenfunctions, and off-axis complex-argument polynomial beams must be used. New beam transformations for these complex-argument modes are reported. Stability criteria are developed, and mode selection in laser resonators that contain tilted, displaced, or curved complex optical elements is discussed. Close

• 19. [Article] Beam modes in complex lenslike media and resonators

  General sets of higher-order beam modes are derived for light propagation in media having spatial variations of the gain or loss. The resulting expressions are also valid for propagation through conventional ...

  Citation × Citation Citation Abstract Copy Title: Beam modes in complex lenslike media and resonators Author: Casperson, Lee W. Year: 1976 General sets of higher-order beam modes are derived for light propagation in media having spatial variations of the gain or loss. The resulting expressions are also valid for propagation through conventional optical elements and graded transmission filters. The four basic mode sets obtained include off-axis Hermite-Gaussian and Laguerre-Gaussian modes of both real and complex argument. A procedure is developed for finding the resonant modes of laser oscillators containing arbitrary complex lens elements, and the mode stability properties of lasers can be interpreted physically by means of these formulas. Title: Beam modes in complex lenslike media and resonators Author: Casperson, Lee W. Year: 1976 General sets of higher-order beam modes are derived for light propagation in media having spatial variations of the gain or loss. The resulting expressions are also valid for propagation through conventional optical elements and graded transmission filters. The four basic mode sets obtained include off-axis Hermite-Gaussian and Laguerre-Gaussian modes of both real and complex argument. A procedure is developed for finding the resonant modes of laser oscillators containing arbitrary complex lens elements, and the mode stability properties of lasers can be interpreted physically by means of these formulas. Close

• 20. [Article] Few-Cycle Pulses in Two-Level Media

  Techniques for producing, measuring, and applying ever shorter electromagnetic pulses are being developed for incorporation in a variety of modern high-speed systems. In many cases these pulses are at ...

  Citation × Citation Citation Abstract Copy Title: Few-Cycle Pulses in Two-Level Media Author: Casperson, Lee W. Year: 1998 Techniques for producing, measuring, and applying ever shorter electromagnetic pulses are being developed for incorporation in a variety of modern high-speed systems. In many cases these pulses are at most a few cycles in length, and so-called half-cycle electromagnetic pulses are also widely employed. The interaction of such pulses with two-level media is considered here in detail, and these media are basic to many of the absorbing and amplifying configurations of optics and laser studies. Significant delays and distortion of the resulting polarization and population pulses can occur, and nonlinear optical effects are also revealed. The limitations of the parity, rate-equation, and rotating-wave approximations for the characterization of such few-cycle interactions are also explored. Title: Few-Cycle Pulses in Two-Level Media Author: Casperson, Lee W. Year: 1998 Techniques for producing, measuring, and applying ever shorter electromagnetic pulses are being developed for incorporation in a variety of modern high-speed systems. In many cases these pulses are at most a few cycles in length, and so-called half-cycle electromagnetic pulses are also widely employed. The interaction of such pulses with two-level media is considered here in detail, and these media are basic to many of the absorbing and amplifying configurations of optics and laser studies. Significant delays and distortion of the resulting polarization and population pulses can occur, and nonlinear optical effects are also revealed. The limitations of the parity, rate-equation, and rotating-wave approximations for the characterization of such few-cycle interactions are also explored. Close