- Email: [email protected]
Second European electro-optics conference
F. A. A. Amin and A. Luxmoore (University College, Swansea) described how they have used this method as a means of practical strain measurement, claiming an accuracy of 0.1 ,um in the determination of relative displacement. The technique has been applied to the investigation of crack formation and creep effects. An important extension of the method that they have developed is the comparison of two separately exposed speckle photographs; this eliminates the troublesome effects of rigid body motion. It also leads to the possibility of following changes in machine components subjected to repeated stress in service; they are photographed in the laboratory before and after running the test. The appropriate choice of Loughborough University as the venue of this conference was evident from the contribution made by its staff. As an introduction, J. N. Butters gave an outline of the principles of speckle interferometry as a means of high precision measurement. Although the early work was done photographically, it is the possibility of using television techniques with a speckle pattern that gives it the great advantage over holography. The signals picked up can be electronically processed and displayed, on line, on a bright screen. One pattern can be compared with a pre-recorded pattern to give ‘correlation fringes’ which are exactly analogous to the fringes obtained using interference holography. J. A. Leendertz described some of the applications, using examples recorded on video-tape and displayed on tv monitors. These included the measurement of vibration, in-plane displacement, bending moment, and shape comparison using twowavelength contouring. The latter provides a de-sensitized method of measuring imperfections of form, and as a demonstration an interferometer was used to check the sphericity of ground glass mirror blanks. The advantage of speckle interferometry over holography for the measurement of surface strain was illustrated by D. Denby with examples of work on carbon fibre composites and on rubber specimens. Linear and shear strain could be measured to an accuracy of 5%, and compresssive and tensile strains distinguished by live fringe examination. The associated problem of determining the complete strain tensor at any point was tackled by R. Jones, who described a composite speckle interferometer with three illuminating beams. Using photographic recording, the elastic constants of materials could be measured with this instrument. For the optical filtering necessary to obtain the speckle correlation fringes, a white light diffractometer system was used.
described a double-exposure technique that uses three or four apertures placed in front of the lens. This method is analogous to the multi-beam illumination techniques of Leendertz and Jones; it yields correlation fringe patterns that can be analysed to give components of strain similar to those obtained conventionally with a rosette strain gauge. A paper from C. Forno (NPL) reminded the conference that speckle is not necessarily confined to the use of laser light. In collaboration with J. M. Burch, he has devised displacement-measuring methods that use a camera having four slots in the shape of a square in the lens pupil. With white light illumination and an object having regular periodicity (such as woven material), distortion contours could be distinctly shown up when the image was filtered in a suitable optical system. The analogy with laser speckle was brought out by the fact that the system works when a random array of glass beads covers the surface. The speckle-like nature of the unresolved image of a star photographed through the Earth’s atmosphere can be used to give information about its nature ~ whether it is a doublet for example. J. C. Dainty (Queen Elizabeth College, London) surveyed the considerable effort, both theoretical and experimental, which is being mounted by astronomers to exploit this technique. He dealt with the limitations imposed, and described some of the programmes being planned for collecting and processing the large number of photographs required. At the other end of the size scale, the final paper from L. H. Tanner (Brighton Polytechnic) described the testing of cameras by laser speckle. In a simple and elegant way Tanner showed that by observing the speckle pattern in the plane of the camera lens, which is formed by scatter at the film, the perfection of focus can be judged to about one tenth of the Raylcigh limit. The method, which is equivalent to the Foucault knife-edge test, allows all the four primary and eight secondary aberration terms to be measured, and also indicates any film position error. The idea of holding a short overnight conference is a good one, giving the participants the opportunity to have informal discussions during the evening. The excellent dinner provided by the University helped to further this. Even so, it was a pity that the programme did not leave time at the end for a general discussion of a subject which evidently provides a great deal of academic interest and a diversity of practical applications.
In a further contribution on speckle interferometry, Fu-Pen-Chiang (University of New York, Stony Brook)
Second Montreux,
European
Switzerland,
2-5
April
electro-optics 1974
Nearly 400 delegates drawn primarily from Western countries attended the meeting. Some 65 technical papers were presented in three parallel sessions. In addition there were two seminars, one on optical communications and one on electro-optics in biology and medicine, and an optional (ie not included in the basic conference fee) five hour series of lectures on the management of R and D projects. This meeting was one of the new vogue of commercial conferences: it was sponsored by a number of national
186
conference
Institutes and organized by Mack-Brooks Exhibitions (UK). Attendance was not cheap ~ SF 260 (about 536 or $85) for the basic conference fee without a copy of the proceedings, and for this sort of money one felt entitled to a flawlessly organized smooth running meeting. This alas was not the case, and many of the shortcomings which WC have all seen at technical meetings were present at this one. Speakers did not turn up when their time came, sessions started late, the initially announced programme was subject
OPTICS AND LASER TECHNOLOGY
AUGUST
1974
to a large number of alterations, the abstracts available at the conference were incomplete, and in many cases the authors names were given without the affiliation - a serious omission as one could only attend a third of the talks. Presumably we shall find it all in the proceedings. On this point, a suggestion for the next meeting in the series: explore the possibility of having the proceedings available by the last day of the conference (I hesitate to say the first). It is not too much to ask of speakers to have their manuscripts ready in a prescribed format at the beginning of the meeting. With today’s copying facilities - particularly in Switzerland where a network of specialized rapid-copying firms exists - there would be time enough to produce a perfectly acceptable result. Despite these shortcomings, which are after all the impressions of only one person, it proved to be a worthwhile meeting. Some first class speakers were present, and quite apart from a number of interesting papers on specifics, several definite trends for the whole field of electro-optics became visible. In general the papers tended to be tutorial, with few startling breakthroughs: not surprising in view of the strong applications (and hence commercial) orientation of much of the field. Meetings of this nature serve a valuable purpose if in addition to bringing people in related areas together, they help to disseminate the enormous amount of technical information locked within the walls of industrial R and D departments. Perhaps the most significant trend in this whole area is the emergence of fibre-optics technology in the field of communications. This trend was clearly shown by H. Elion (A. D. Little, Cambridge, Massachusetts) who gave results of a marketing study of projected growth of world electro. optic markets. Electra-optic telecommunications is seen as the largest area of growth in the whole electronics field for the latter half of the 1970s and into the 1980s. Fibre optics will play a substantial part in this growth. Several speakers made the point that fibre optics are unique in that they allow a ‘graceful’ growth of information capacity, where the effective limits are set not by the fibre but by the interface equipment. Couple this to the potentially low cost of tibres, their low weight and space requirements, and the immunity to electrical interference and radiation, and one then foresees their use not only as trunk lines between major centres but also as duplex links between a local information centre and the consumer. On the fibres themselves R. Maurer (Corning Glass Works) described recent progress in manufacture which has resulted in 3 km long fibres with average attenuations in the near infra-red of only 2 dB km-l. One may ask who will supply the funds for this major revolution in telecommunications, and there is evidence that some may come from military or government sources. A. Klein (US Navy) described a feasibility demonstration underway in which the existing data lines in a US naval aircraft are being replaced with fibreoptic links. On the vital problem of an adequate signal source for fibre guides R. Garmire (Standard Telecommunication Laboratories, UK) gave a lucid account of the STL work on cw room temperature GaAs lasers. With the ‘magic’ material GaAlAs, and a double hetero-structure technique, the carriers can be confined to a layer a few thousand Angstroms thick. Room temperature cw outputs of a few milliwatts with current thresholds below 1 000 A cm-2 are now possible. These devices have been modulated at frequencies up to 1 GHz, and lifetimes seem to be rapidly
OPTICS AND LASER TECHNOLOGY.
AUGUST
1974
187
approaching
the value of 10 000 h reported by Bell Labs.
A second trend in electro-optics is to be seen in the nuclear energy field. The unsolved problem of controlled thermonuclear fusion still finds the high power solid state laser a serious candidats for its solution. Only one paper by A. Bettinger (Laboratoires de Marcoussis, France) dealt specifically with this topic, but others made reference to the field. With the neodymium-doped glass laser there seems to be reasonable expectation that the critical values of 5-10 kJ in the 100 ps pulse range can be achieved in the next decade. An interesting but perhaps less reassuring development in the high energy laser field is the possible separation of isotopes by means of either photo-ionization or photodissociation processes. Irradiation of an isotope mixture with narrow band radiation under the correct conditions can lead to a high degree of chemical specivity which then allows the isotopes to be separated by relatively simple means. Infra-red irradiation of U235 + U238 mixtures was given as an example by K. Kompa (Max-Planck Institute, Munich) and J. Steinfeld (Massachusetts Institute of Technology). Though there is general agreement that U235 will be desperately needed in coming years as a nuclear fuel source, the same unanimity does not hold over the availability of a cheap and simple process for its production. This is possibly an area where one views progress in science with mixed feelings. A session on environmental protection added a topical flavour and revealed a further trend. Techniques for the measurement of air and water (and soil) are tending to shift away from standard chemical methods towards physical methods. D. Kroon (Philips, Eindhoven) reviewed electrooptic approaches to the remote measurement of air and water by means of LIDAR (light detection and ranging), correlation spectroscopy, and Raman scattering techniques. Such instruments, which depend on back scattering over distances of up to several kilometres, are necessarily very expensive at present, and are consequently seen as an institutional service (for example airport slant-visibility and cloud-ceiling measurements) or as a community service for the measurement of pollutant levels in the atmosphere. R. Geluk (Optische Industrie te Delft, Holland) described a simple two-channel image converter which transposed the visible and near infra-red spectra into two visible colours. The tube could be used to detect abnormal chlorophyl content in foliage. The final day of the meeting provided a large number of papers on specific results, and it was unfortunate that, for example, sessions on a - electro-optical storage, memories, and holography; b - testing, measuring, and materialsprocessing; and c - opto-electronic sensing and display components, were all run in parallel. Many delegates would have welcomed the chance to attend all three sessions. G. Labrunie et al (CENG, Grenoble, France) described a 128 x 128 bit liquid crystal page composer that worked by field-induced birefringence. Data transfer rates using pulse techniques were in excess of 1 Mbit s-l, the whole page writing time was around 2 ms, and the natural storage time of the cells was 5 ms. This group is working on a page composer of similar capacity which will have an eight-step grey scale capability. Somewhat higher writing speeds (up to 100 Mbit s-i were shown by P. Waterworth and M. Lee (Plessey, UK) with their PLZT linear array holographic serial recording system. A further storage method was reported by J. Krumme (Philips, Hamburg) who described a DDL 4872
188
OPTICS AND LASER TECHNOLOGY.
AUGUST
1974
new magneto-optic memory material based on compensation wall domains; compared to the conventional thermomagnetic memory, this showed reduced requirements for the magnitude of the uniaxial anisotropy and increased write-in sensitivity. The current state of the art of gallium phosphide yellow and green light-emitting diode displays was given by T. Knibb et al (Plessey), who reported on a 30 element display made using vapour phase epitaxy; the 25 pm x 50 pm units had a brightness of 10 000 footlambert at 10 mA. An alternative type of display amenable to large scale integration techniques was described by W. Petty and A. Cribbs (Rank Xerox, UK). Their ac plasma displays in which storage of charged particles on dielectric surfaces provides inherent memory, produced impressive results. Element densities of 3 600 per square inch on a 5 12 x 5 12 array are now possible, and both higher densities and larger panels are practical. To close this brief account of some of the specific topics, mention should be made of two analogue devices now available for real-time optical processing operations. J. Feinleib and S. Iwasa (Itek, USA) reported on the PROM (Pockel’s read-out optical modulator). The electronic characteristics of the device (basically a thin plate of bismuth silicon oxide) enable level slicing, edge enhancement, and contrast inversion of the stored image. These properties, useful for incoherent processing, also allow zero-order supression in coherent processing applications. The device has a high sensitivity in the blue (equivalent to an ASA speed of around one) and up to 500 lines resolution. A second device with similar uses - the Ruticon - was described by N. Sheridan (Xerox, Palo Alto). The Ruticon is a photo-conductorelastomer sandwich between conducting electrodes and allows image storage in the form of phase information with resolutions in excess of 100 lines mm-l. Besides being useful for non-coherent to coherent conversion applications, the Ruticon can be used for non-coherent procedures such as image addition and subtraction, wavelength conversion, and image intensification.
Finally a few remarks on the separate course of seminars on the management of technical innovation. The seminars were presented jointly by the International Institute for the Management of Technology (Milan), and the Manchester Business School. The lectures can best be summarized by mentioning a few of the ‘golden rules’ of innovation management put to those present: 1. Technical innovation limits to growth. 2. Concentrate market.
is the only way to overcome the
on needs and adapt technology
to the
3. Contact with the world outside the R and D department is essential. 4. Creativity should be fostered by extracting all the ideas within a group. One can use other peoples ideas, and one must allow ones own ideas to be used by others. 5. Creativity is needed not only at the innovative stage of a new product but also at the engineering, production, and marketing stages. 6. It is the final user who must be served. A completely de-bugged product is more important than being first in the field. 7. Sub-critical efforts on a project have little chance of beating the combined effects of progress and the competition. An adequate team is required combined with the flexibility to change to another project once a goal is reached. These rules sounded like common sense to most, but it is sometimes surprisingly difficult to set such intuitive feelings down in black and white. The rules are simple but, as with the ones for playing the stock-market, the successful application is quite another matter.
D. L. Greenaway
BOOKS Lasers in industry Edited
by S. S. Charschan
A Western Electric Series Publication, Reinhold, 1973, pp 640, 512.25
Van Nostrand
Ten members of an American company have each written a chapter of this comprehensive book. The writers are specialists in particular fields and they present an up-to-date account of laser applications technology for the engineer in industry. The first chapter deals with laser fundamentals in a straightforward way, requiring only a basic knowledge of physics. The second includes more basic physics and a fair amount of theory on the interaction of electromagnetic radiation with materials. The following three chapters cover the use of the laser as a heat source. Chapter 3 is an introduction
OPTICS AND LASER TECHNOLOGY.
AUGUST
1974
to laser processing fundamentals which will help the applications engineer avoid some of the many pitfalls awaiting him. Chapter 4 gives examples of successful heating applications and details of solving specific problems: welding, cutting, drilling, and micro-machining are dealt with in a practical manner, and the section on analysing and solving a welding problem is particularly good. Chapter 5 discusses the use of lasers for heat treatment and for inducing permanent changes in materials. This area has lagged behind in the widening field of laser applications so there are few specific examples. The next three chapters describe the optical properties of a laser output. Chapter 6 discusses how reflection and scattering of laser light is used in measurement applications. The section on reflection covers surface diagnostics and ellipsometry in some detail but only briefly reviews ranging, distance, and Doppler measurements. The remainder of the chapter discusses Raleigh, Raman, and Brillouin
189
described a double-exposure technique that uses three or four apertures placed in front of the lens. This method is analogous to the multi-beam illumination techniques of Leendertz and Jones; it yields correlation fringe patterns that can be analysed to give components of strain similar to those obtained conventionally with a rosette strain gauge. A paper from C. Forno (NPL) reminded the conference that speckle is not necessarily confined to the use of laser light. In collaboration with J. M. Burch, he has devised displacement-measuring methods that use a camera having four slots in the shape of a square in the lens pupil. With white light illumination and an object having regular periodicity (such as woven material), distortion contours could be distinctly shown up when the image was filtered in a suitable optical system. The analogy with laser speckle was brought out by the fact that the system works when a random array of glass beads covers the surface. The speckle-like nature of the unresolved image of a star photographed through the Earth’s atmosphere can be used to give information about its nature ~ whether it is a doublet for example. J. C. Dainty (Queen Elizabeth College, London) surveyed the considerable effort, both theoretical and experimental, which is being mounted by astronomers to exploit this technique. He dealt with the limitations imposed, and described some of the programmes being planned for collecting and processing the large number of photographs required. At the other end of the size scale, the final paper from L. H. Tanner (Brighton Polytechnic) described the testing of cameras by laser speckle. In a simple and elegant way Tanner showed that by observing the speckle pattern in the plane of the camera lens, which is formed by scatter at the film, the perfection of focus can be judged to about one tenth of the Raylcigh limit. The method, which is equivalent to the Foucault knife-edge test, allows all the four primary and eight secondary aberration terms to be measured, and also indicates any film position error. The idea of holding a short overnight conference is a good one, giving the participants the opportunity to have informal discussions during the evening. The excellent dinner provided by the University helped to further this. Even so, it was a pity that the programme did not leave time at the end for a general discussion of a subject which evidently provides a great deal of academic interest and a diversity of practical applications.
In a further contribution on speckle interferometry, Fu-Pen-Chiang (University of New York, Stony Brook)
Second Montreux,
European
Switzerland,
2-5
April
electro-optics 1974
Nearly 400 delegates drawn primarily from Western countries attended the meeting. Some 65 technical papers were presented in three parallel sessions. In addition there were two seminars, one on optical communications and one on electro-optics in biology and medicine, and an optional (ie not included in the basic conference fee) five hour series of lectures on the management of R and D projects. This meeting was one of the new vogue of commercial conferences: it was sponsored by a number of national
186
conference
Institutes and organized by Mack-Brooks Exhibitions (UK). Attendance was not cheap ~ SF 260 (about 536 or $85) for the basic conference fee without a copy of the proceedings, and for this sort of money one felt entitled to a flawlessly organized smooth running meeting. This alas was not the case, and many of the shortcomings which WC have all seen at technical meetings were present at this one. Speakers did not turn up when their time came, sessions started late, the initially announced programme was subject
OPTICS AND LASER TECHNOLOGY
AUGUST
1974
to a large number of alterations, the abstracts available at the conference were incomplete, and in many cases the authors names were given without the affiliation - a serious omission as one could only attend a third of the talks. Presumably we shall find it all in the proceedings. On this point, a suggestion for the next meeting in the series: explore the possibility of having the proceedings available by the last day of the conference (I hesitate to say the first). It is not too much to ask of speakers to have their manuscripts ready in a prescribed format at the beginning of the meeting. With today’s copying facilities - particularly in Switzerland where a network of specialized rapid-copying firms exists - there would be time enough to produce a perfectly acceptable result. Despite these shortcomings, which are after all the impressions of only one person, it proved to be a worthwhile meeting. Some first class speakers were present, and quite apart from a number of interesting papers on specifics, several definite trends for the whole field of electro-optics became visible. In general the papers tended to be tutorial, with few startling breakthroughs: not surprising in view of the strong applications (and hence commercial) orientation of much of the field. Meetings of this nature serve a valuable purpose if in addition to bringing people in related areas together, they help to disseminate the enormous amount of technical information locked within the walls of industrial R and D departments. Perhaps the most significant trend in this whole area is the emergence of fibre-optics technology in the field of communications. This trend was clearly shown by H. Elion (A. D. Little, Cambridge, Massachusetts) who gave results of a marketing study of projected growth of world electro. optic markets. Electra-optic telecommunications is seen as the largest area of growth in the whole electronics field for the latter half of the 1970s and into the 1980s. Fibre optics will play a substantial part in this growth. Several speakers made the point that fibre optics are unique in that they allow a ‘graceful’ growth of information capacity, where the effective limits are set not by the fibre but by the interface equipment. Couple this to the potentially low cost of tibres, their low weight and space requirements, and the immunity to electrical interference and radiation, and one then foresees their use not only as trunk lines between major centres but also as duplex links between a local information centre and the consumer. On the fibres themselves R. Maurer (Corning Glass Works) described recent progress in manufacture which has resulted in 3 km long fibres with average attenuations in the near infra-red of only 2 dB km-l. One may ask who will supply the funds for this major revolution in telecommunications, and there is evidence that some may come from military or government sources. A. Klein (US Navy) described a feasibility demonstration underway in which the existing data lines in a US naval aircraft are being replaced with fibreoptic links. On the vital problem of an adequate signal source for fibre guides R. Garmire (Standard Telecommunication Laboratories, UK) gave a lucid account of the STL work on cw room temperature GaAs lasers. With the ‘magic’ material GaAlAs, and a double hetero-structure technique, the carriers can be confined to a layer a few thousand Angstroms thick. Room temperature cw outputs of a few milliwatts with current thresholds below 1 000 A cm-2 are now possible. These devices have been modulated at frequencies up to 1 GHz, and lifetimes seem to be rapidly
OPTICS AND LASER TECHNOLOGY.
AUGUST
1974
187
approaching
the value of 10 000 h reported by Bell Labs.
A second trend in electro-optics is to be seen in the nuclear energy field. The unsolved problem of controlled thermonuclear fusion still finds the high power solid state laser a serious candidats for its solution. Only one paper by A. Bettinger (Laboratoires de Marcoussis, France) dealt specifically with this topic, but others made reference to the field. With the neodymium-doped glass laser there seems to be reasonable expectation that the critical values of 5-10 kJ in the 100 ps pulse range can be achieved in the next decade. An interesting but perhaps less reassuring development in the high energy laser field is the possible separation of isotopes by means of either photo-ionization or photodissociation processes. Irradiation of an isotope mixture with narrow band radiation under the correct conditions can lead to a high degree of chemical specivity which then allows the isotopes to be separated by relatively simple means. Infra-red irradiation of U235 + U238 mixtures was given as an example by K. Kompa (Max-Planck Institute, Munich) and J. Steinfeld (Massachusetts Institute of Technology). Though there is general agreement that U235 will be desperately needed in coming years as a nuclear fuel source, the same unanimity does not hold over the availability of a cheap and simple process for its production. This is possibly an area where one views progress in science with mixed feelings. A session on environmental protection added a topical flavour and revealed a further trend. Techniques for the measurement of air and water (and soil) are tending to shift away from standard chemical methods towards physical methods. D. Kroon (Philips, Eindhoven) reviewed electrooptic approaches to the remote measurement of air and water by means of LIDAR (light detection and ranging), correlation spectroscopy, and Raman scattering techniques. Such instruments, which depend on back scattering over distances of up to several kilometres, are necessarily very expensive at present, and are consequently seen as an institutional service (for example airport slant-visibility and cloud-ceiling measurements) or as a community service for the measurement of pollutant levels in the atmosphere. R. Geluk (Optische Industrie te Delft, Holland) described a simple two-channel image converter which transposed the visible and near infra-red spectra into two visible colours. The tube could be used to detect abnormal chlorophyl content in foliage. The final day of the meeting provided a large number of papers on specific results, and it was unfortunate that, for example, sessions on a - electro-optical storage, memories, and holography; b - testing, measuring, and materialsprocessing; and c - opto-electronic sensing and display components, were all run in parallel. Many delegates would have welcomed the chance to attend all three sessions. G. Labrunie et al (CENG, Grenoble, France) described a 128 x 128 bit liquid crystal page composer that worked by field-induced birefringence. Data transfer rates using pulse techniques were in excess of 1 Mbit s-l, the whole page writing time was around 2 ms, and the natural storage time of the cells was 5 ms. This group is working on a page composer of similar capacity which will have an eight-step grey scale capability. Somewhat higher writing speeds (up to 100 Mbit s-i were shown by P. Waterworth and M. Lee (Plessey, UK) with their PLZT linear array holographic serial recording system. A further storage method was reported by J. Krumme (Philips, Hamburg) who described a DDL 4872
188
OPTICS AND LASER TECHNOLOGY.
AUGUST
1974
new magneto-optic memory material based on compensation wall domains; compared to the conventional thermomagnetic memory, this showed reduced requirements for the magnitude of the uniaxial anisotropy and increased write-in sensitivity. The current state of the art of gallium phosphide yellow and green light-emitting diode displays was given by T. Knibb et al (Plessey), who reported on a 30 element display made using vapour phase epitaxy; the 25 pm x 50 pm units had a brightness of 10 000 footlambert at 10 mA. An alternative type of display amenable to large scale integration techniques was described by W. Petty and A. Cribbs (Rank Xerox, UK). Their ac plasma displays in which storage of charged particles on dielectric surfaces provides inherent memory, produced impressive results. Element densities of 3 600 per square inch on a 5 12 x 5 12 array are now possible, and both higher densities and larger panels are practical. To close this brief account of some of the specific topics, mention should be made of two analogue devices now available for real-time optical processing operations. J. Feinleib and S. Iwasa (Itek, USA) reported on the PROM (Pockel’s read-out optical modulator). The electronic characteristics of the device (basically a thin plate of bismuth silicon oxide) enable level slicing, edge enhancement, and contrast inversion of the stored image. These properties, useful for incoherent processing, also allow zero-order supression in coherent processing applications. The device has a high sensitivity in the blue (equivalent to an ASA speed of around one) and up to 500 lines resolution. A second device with similar uses - the Ruticon - was described by N. Sheridan (Xerox, Palo Alto). The Ruticon is a photo-conductorelastomer sandwich between conducting electrodes and allows image storage in the form of phase information with resolutions in excess of 100 lines mm-l. Besides being useful for non-coherent to coherent conversion applications, the Ruticon can be used for non-coherent procedures such as image addition and subtraction, wavelength conversion, and image intensification.
Finally a few remarks on the separate course of seminars on the management of technical innovation. The seminars were presented jointly by the International Institute for the Management of Technology (Milan), and the Manchester Business School. The lectures can best be summarized by mentioning a few of the ‘golden rules’ of innovation management put to those present: 1. Technical innovation limits to growth. 2. Concentrate market.
is the only way to overcome the
on needs and adapt technology
to the
3. Contact with the world outside the R and D department is essential. 4. Creativity should be fostered by extracting all the ideas within a group. One can use other peoples ideas, and one must allow ones own ideas to be used by others. 5. Creativity is needed not only at the innovative stage of a new product but also at the engineering, production, and marketing stages. 6. It is the final user who must be served. A completely de-bugged product is more important than being first in the field. 7. Sub-critical efforts on a project have little chance of beating the combined effects of progress and the competition. An adequate team is required combined with the flexibility to change to another project once a goal is reached. These rules sounded like common sense to most, but it is sometimes surprisingly difficult to set such intuitive feelings down in black and white. The rules are simple but, as with the ones for playing the stock-market, the successful application is quite another matter.
D. L. Greenaway
BOOKS Lasers in industry Edited
by S. S. Charschan
A Western Electric Series Publication, Reinhold, 1973, pp 640, 512.25
Van Nostrand
Ten members of an American company have each written a chapter of this comprehensive book. The writers are specialists in particular fields and they present an up-to-date account of laser applications technology for the engineer in industry. The first chapter deals with laser fundamentals in a straightforward way, requiring only a basic knowledge of physics. The second includes more basic physics and a fair amount of theory on the interaction of electromagnetic radiation with materials. The following three chapters cover the use of the laser as a heat source. Chapter 3 is an introduction
OPTICS AND LASER TECHNOLOGY.
AUGUST
1974
to laser processing fundamentals which will help the applications engineer avoid some of the many pitfalls awaiting him. Chapter 4 gives examples of successful heating applications and details of solving specific problems: welding, cutting, drilling, and micro-machining are dealt with in a practical manner, and the section on analysing and solving a welding problem is particularly good. Chapter 5 discusses the use of lasers for heat treatment and for inducing permanent changes in materials. This area has lagged behind in the widening field of laser applications so there are few specific examples. The next three chapters describe the optical properties of a laser output. Chapter 6 discusses how reflection and scattering of laser light is used in measurement applications. The section on reflection covers surface diagnostics and ellipsometry in some detail but only briefly reviews ranging, distance, and Doppler measurements. The remainder of the chapter discusses Raleigh, Raman, and Brillouin
189