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Foundations of laser spectroscopy
BOOKS Optical anecdotes D . J . Lovefl SPIE, 1981, pp 134, $25 In his preface to this volume, the author made the disclaimer 'This book is neither a history nor an optics text', The O E D definition of anecdote is: narrative of detached incident; unpublished details of history. This book certainly complies with the first definition and there are many examples of the second. Apart from a general chronological order, the use of an illuminated initial letter and paragraph markers, each anecdote is an independent essay about a discovery, a scientist or a development In particular, the book puts flesh on names well known to optical scientists - - Young's slits, Fresnel lens, Fourier optics, etc. While it is not strictly necessary to be versed in optics to appreciate the book, such a background certainly makes it more interesting, Indeed, at times the reader can judge for himself whether the right person has been commemorated in the names we now use for specifying optical effects and physical units. There is a lot of historical information here which assists the reader to ponder the effects of chance and change on the lives of optical scientists and on their 'success', whichever way one would wish to define that word. However, the above was not the main intention of the author. His prime purpose, according to his preface, was that those who read it 'be motivated to a greater joy in observing nature's splendours and to extend themselves to further investigations of the nature of light'. In this I find the book fails. In spite of the lightness with which the author says he regards his material, the treatment is very pedagogical and the prose dead pan. There is no communication of enjoyment between the author and this reader. Even the story of the achromatic lens is given a terse and detached treatment with no venturing into the minds of Hall and Dolland and the contentiousness of the patent wrangle. Accepting this limitation, there is a lot in this book to interest the optical scientist and it is certainly worth reading by teachers and lecturers of optics. M.H. Freeman
Modular optical design O.N. Stravroudis Springer, 1982, pp xiii + 199, $39.60 This book, by Orestes Stavroudis, continues in his inimitable style. Some day, no doubt, he will be a subject in a book of optical anecdotes like the one reviewed above. This volume concerns lens design and in particular the initial stages of system set up when the basic aberration relationships are likely to become predetermined. For this Prof Stavroudis insists that a computer is essential. Backs of envelopes, slide rules and calculators will not do. This is certainly the case,
OPTICS AND LASER TECHNOLOGY. DECEMBER 1984
but there are no programs, no flow charts in this book. It is therefore difficult to understand who will benefit from buying it In the main, optical designers express their needs by saying 'give me a good program' while other optical engineers express theirs by saying 'give me a good optical designer'. Neither of these needs are met by reading this book. It would seem that it is written with the needs of the optical design program writer in mind, and these people are not very numerous. For the record, the first chapter reviews paraxial optics and third order aberrations, while the second describes the Delano diagram. The third develops the module idea and the fourth and fifth define its characteristics. It is the sixth chapter where the crux of the concept is dealt with in terms of putting modules together for zero third order aberrations. The seventh chapter extends (a most appropriate word) the concept into fifth and seventh order aberrations. The eighth chapter, all too briefly, gives some examples of the results that can be obtained and is the most readable to the average optical engineer and designer. Chapter nine gives the most explicit justification for the book - - that the modular concept deserves a wider following and understanding. The problem is that such a following has to follow understanding when a book is used to disseminate the information. The number of people with the time and aptitude to gain and use the understanding is less than the number of people who could usefully apply this concept It may be quicker to follow the lead of Professor Doug Sinclair and Dr Mike Kidger and offer a computer package from Optical Sciences Centre. M.H. Freeman
Foundations of laser spectroscopy S. Stenholm John Wiley, 1984, pp viii + 268, £35 Laser spectroscopy is a flourishing field of activity with prospects of ever widening scope as advances are made in laser performance. The field has now matured to the point where textbooks on the subject are needed and this book is a welcome addition. It teaches the theoretical ideas needed to do calculations in laser spectroscopy and, in the authors words, is intended for beginning theorists and experimentalists who lack extensive training in algebraic manipulations. The author, Stig Stenholm, is particularly well qualified to write such a booL having worked for many years on theoretical aspects of lasers and laser spectroscopy, with a prolific output of published work. Chapter one covers background material on electrodynamics and quantum mechanics, with an emphasis on the density matrix, its equation of motion and its interpretation. This is an important topic and it is nice to see it so clearly presented. Chapter two covers the response of the medium to strong fields. Having
325
covered these two chapters the remaining ones can be tackled in any order. They include coverage of the physical basis of laser operation, a range of topics central to laser spectroscopy, such as saturation spectroscopy, Doppler-free two-photon spectroscopy, multiphoton processes, coherence phenomena, and the effects of field fluctuations. The final chapter deals with quantization of the electromagnetic field and goes on to discuss resonance fluorescence in a strong field. Each chapter concludes with a page or two of comments and references, a useful feature for those who wish to delve further. It is a pity that no problems were included since these are an asset to a textbook It should also be noted that throughout the book the discussion is confined to steady state spectroscopy and so does not cover transient coherent p h e n o m e n a such as photon echoes and the like. In summary, this is an attractive book, giving a clear and detailed account of the foundations of laser spectroscopy, which will be particularly useful to people entering the field, but also a useful addition to the bookshelves of older hands. D. C.. H a n n a
High speed photography, videography and photonics
The proceedings are well produced in the way we are accustomed to with SPIE publications - - half-tones being accurately reproduced by screening methods. The volume is a valuable one for all workers in the development and application areas of the subject. A L : Huston
Mode-locking in solid state and semiconductor lasers M.S. Demokan Research Studies, 1982, pp xi + 227, £18.50 At an early stage in the development of the laser, the technique was developed of producing trains of pulses of extremely short duration, using the fact that the phases of several adjacent longitudinal laser modes could be locked together. The resulting pulses, with durations in the picosecond regime and powers of the order of gigawatts, enabled a whole new field of highspeed, high-intensity p h e n o m e n a to be opened up. Lifetime measurements in the picosecond range became possible, Raman, Brillouin and Rayleigh scattering studies became routine, high-density plasmas could be produced and, with the help of frequencymixing techniques, intense sources in the hitherto difficult regions of the far infra-red and millimetre wave regions became possible.
A meeting on high-speed photography, videography and photonics was held at San Diego, California, August 23-25, 1983, just one year after the 15th International Congress on the same subjects, and at the same venue. It might be inferred from this that the later meeting had little to add to the material presented at its predecessor, but such is not the case.
Although the technique of mode-locking appears straightforward to apply, the attendant processes are extremely complex and need to be well understood if clean, regular, reproducible pulses are to be produced. In this book Dr D e m o k a n covers the theoretical background to passive and active mode-locking in crystal lasers and also deals with semiconductor lasers. A few parameter values and pulse duration measurements are included, although there is very little on experimental results.
Three of the major US National Laboratories, namely, Los Alamos, Lawrence Livermore and Sandia, contributed only 13 of the 175 papers presented at the 15th Congress, but no less than 16 of the 40 papers at the 1983 meeting. These papers were mostly concerned with the subjects of soft x-ray streak photography and interferometric methods for velocity measurement, and constitute a valuable collection of up-to-date reports on these topics.
Since the publication of the book the record for the shortest duration pulse has been pushed down to the femtosecond region from the 15 ps figure referred to, an indication of the rapidity with which the field is still developing. This is probably the first exhaustive treatment of the subject and so should prove useful to workers in the field. It is well written and gives a reasonably balanced view of the important work done over the last 15 years or so.
A keynote address by Dr J.S. Courtney-Pratt discussed the advances made in high-speed photography 1972-83. A valuable feature of this paper is a list of 40 references in which Dr Courtney-Pratt has extracted the most significant papers from the vast literature during that period.
O.S. Heavens
Edited by D.L. Paisley SPIE Proceedings, Volume 427, 1983, pp vi + 265, $49
There are several papers discussing the properties and uses of microchannel plates, including improvements in the performance of the plates themselves, and developments in ways of using them in optical shuttering devices with durations as short as 10-9 s. One session of the meeting was devoted to high-speed videography, a field in which there has been considerable activity in recent years, due largely to the advent of satisfactory solid-state sensors, and remarkable progress is being made. The reader of the proceedings is brought right up-to-date with several papers on new developments in the field, for example, combining high-speed video with x-ray intensifiers to provide a system for dynamic radiography.
326
Adaptive optics systems and technology Edited by R.J. Becherer and B.A. Horwitz SPIE Proceedings, Volume 365, pp 168, $49 Adaptive optics makes possible the operation of large aperture optical systems with performance approaching the theoretical limits set by diffraction. Major advances towards this have been made recently and these proceedings present reports of these accomplishments. The papers were presented in August 1983 at San Diego, California. There are six sessions: imaging applications (three papers); laser beam control systems developments (two papers): and intracavity techniques (three papers); adaptive system analytic considerations (four papers); new adaptive elements and associated optical components (four papers) and non-linear phase conjugation (two papers). The papers of session one deal with telescopes. Sessions two and three papers fit well into the session
OPTICS AND LASER TECHNOLOGY. DECEMBER 1984
Modular optical design O.N. Stravroudis Springer, 1982, pp xiii + 199, $39.60 This book, by Orestes Stavroudis, continues in his inimitable style. Some day, no doubt, he will be a subject in a book of optical anecdotes like the one reviewed above. This volume concerns lens design and in particular the initial stages of system set up when the basic aberration relationships are likely to become predetermined. For this Prof Stavroudis insists that a computer is essential. Backs of envelopes, slide rules and calculators will not do. This is certainly the case,
OPTICS AND LASER TECHNOLOGY. DECEMBER 1984
but there are no programs, no flow charts in this book. It is therefore difficult to understand who will benefit from buying it In the main, optical designers express their needs by saying 'give me a good program' while other optical engineers express theirs by saying 'give me a good optical designer'. Neither of these needs are met by reading this book. It would seem that it is written with the needs of the optical design program writer in mind, and these people are not very numerous. For the record, the first chapter reviews paraxial optics and third order aberrations, while the second describes the Delano diagram. The third develops the module idea and the fourth and fifth define its characteristics. It is the sixth chapter where the crux of the concept is dealt with in terms of putting modules together for zero third order aberrations. The seventh chapter extends (a most appropriate word) the concept into fifth and seventh order aberrations. The eighth chapter, all too briefly, gives some examples of the results that can be obtained and is the most readable to the average optical engineer and designer. Chapter nine gives the most explicit justification for the book - - that the modular concept deserves a wider following and understanding. The problem is that such a following has to follow understanding when a book is used to disseminate the information. The number of people with the time and aptitude to gain and use the understanding is less than the number of people who could usefully apply this concept It may be quicker to follow the lead of Professor Doug Sinclair and Dr Mike Kidger and offer a computer package from Optical Sciences Centre. M.H. Freeman
Foundations of laser spectroscopy S. Stenholm John Wiley, 1984, pp viii + 268, £35 Laser spectroscopy is a flourishing field of activity with prospects of ever widening scope as advances are made in laser performance. The field has now matured to the point where textbooks on the subject are needed and this book is a welcome addition. It teaches the theoretical ideas needed to do calculations in laser spectroscopy and, in the authors words, is intended for beginning theorists and experimentalists who lack extensive training in algebraic manipulations. The author, Stig Stenholm, is particularly well qualified to write such a booL having worked for many years on theoretical aspects of lasers and laser spectroscopy, with a prolific output of published work. Chapter one covers background material on electrodynamics and quantum mechanics, with an emphasis on the density matrix, its equation of motion and its interpretation. This is an important topic and it is nice to see it so clearly presented. Chapter two covers the response of the medium to strong fields. Having
325
covered these two chapters the remaining ones can be tackled in any order. They include coverage of the physical basis of laser operation, a range of topics central to laser spectroscopy, such as saturation spectroscopy, Doppler-free two-photon spectroscopy, multiphoton processes, coherence phenomena, and the effects of field fluctuations. The final chapter deals with quantization of the electromagnetic field and goes on to discuss resonance fluorescence in a strong field. Each chapter concludes with a page or two of comments and references, a useful feature for those who wish to delve further. It is a pity that no problems were included since these are an asset to a textbook It should also be noted that throughout the book the discussion is confined to steady state spectroscopy and so does not cover transient coherent p h e n o m e n a such as photon echoes and the like. In summary, this is an attractive book, giving a clear and detailed account of the foundations of laser spectroscopy, which will be particularly useful to people entering the field, but also a useful addition to the bookshelves of older hands. D. C.. H a n n a
High speed photography, videography and photonics
The proceedings are well produced in the way we are accustomed to with SPIE publications - - half-tones being accurately reproduced by screening methods. The volume is a valuable one for all workers in the development and application areas of the subject. A L : Huston
Mode-locking in solid state and semiconductor lasers M.S. Demokan Research Studies, 1982, pp xi + 227, £18.50 At an early stage in the development of the laser, the technique was developed of producing trains of pulses of extremely short duration, using the fact that the phases of several adjacent longitudinal laser modes could be locked together. The resulting pulses, with durations in the picosecond regime and powers of the order of gigawatts, enabled a whole new field of highspeed, high-intensity p h e n o m e n a to be opened up. Lifetime measurements in the picosecond range became possible, Raman, Brillouin and Rayleigh scattering studies became routine, high-density plasmas could be produced and, with the help of frequencymixing techniques, intense sources in the hitherto difficult regions of the far infra-red and millimetre wave regions became possible.
A meeting on high-speed photography, videography and photonics was held at San Diego, California, August 23-25, 1983, just one year after the 15th International Congress on the same subjects, and at the same venue. It might be inferred from this that the later meeting had little to add to the material presented at its predecessor, but such is not the case.
Although the technique of mode-locking appears straightforward to apply, the attendant processes are extremely complex and need to be well understood if clean, regular, reproducible pulses are to be produced. In this book Dr D e m o k a n covers the theoretical background to passive and active mode-locking in crystal lasers and also deals with semiconductor lasers. A few parameter values and pulse duration measurements are included, although there is very little on experimental results.
Three of the major US National Laboratories, namely, Los Alamos, Lawrence Livermore and Sandia, contributed only 13 of the 175 papers presented at the 15th Congress, but no less than 16 of the 40 papers at the 1983 meeting. These papers were mostly concerned with the subjects of soft x-ray streak photography and interferometric methods for velocity measurement, and constitute a valuable collection of up-to-date reports on these topics.
Since the publication of the book the record for the shortest duration pulse has been pushed down to the femtosecond region from the 15 ps figure referred to, an indication of the rapidity with which the field is still developing. This is probably the first exhaustive treatment of the subject and so should prove useful to workers in the field. It is well written and gives a reasonably balanced view of the important work done over the last 15 years or so.
A keynote address by Dr J.S. Courtney-Pratt discussed the advances made in high-speed photography 1972-83. A valuable feature of this paper is a list of 40 references in which Dr Courtney-Pratt has extracted the most significant papers from the vast literature during that period.
O.S. Heavens
Edited by D.L. Paisley SPIE Proceedings, Volume 427, 1983, pp vi + 265, $49
There are several papers discussing the properties and uses of microchannel plates, including improvements in the performance of the plates themselves, and developments in ways of using them in optical shuttering devices with durations as short as 10-9 s. One session of the meeting was devoted to high-speed videography, a field in which there has been considerable activity in recent years, due largely to the advent of satisfactory solid-state sensors, and remarkable progress is being made. The reader of the proceedings is brought right up-to-date with several papers on new developments in the field, for example, combining high-speed video with x-ray intensifiers to provide a system for dynamic radiography.
326
Adaptive optics systems and technology Edited by R.J. Becherer and B.A. Horwitz SPIE Proceedings, Volume 365, pp 168, $49 Adaptive optics makes possible the operation of large aperture optical systems with performance approaching the theoretical limits set by diffraction. Major advances towards this have been made recently and these proceedings present reports of these accomplishments. The papers were presented in August 1983 at San Diego, California. There are six sessions: imaging applications (three papers); laser beam control systems developments (two papers): and intracavity techniques (three papers); adaptive system analytic considerations (four papers); new adaptive elements and associated optical components (four papers) and non-linear phase conjugation (two papers). The papers of session one deal with telescopes. Sessions two and three papers fit well into the session
OPTICS AND LASER TECHNOLOGY. DECEMBER 1984