Jr. P. J. Oranje. Principes, eigenschappen, toepassingen van gasontladingslampen. Philips technische bibliotheek; Uitgave. Meulenhoff, Amsterdam, 1942, pp. 288.

P. I. Oranje Jr. Principles of Operation, Properties, and Applications of Gas-Discharge Lamps. Philips Technical Library, Amsterdam, 1942.

Nowhere, perhaps, is there such a transparent and clear connection between the elementary atomic characteristics and purely technical parameters as exists in gas-discharge lamps.

Before us, in a bright dust jacket, is a book on gas-discharge lamps, published in Holland at the very height of the Second World War. The dust jacket seems to illustrate the connection indicated above. A blue square with diagrams of the energy levels of mercury and sodium atoms is effectively set against...

Bibliography

against the background of a movable hoisting crane illuminated by sodium lamps. However, on looking more closely, one notices that the mercury diagram contains two gross errors. The 1849 Å line is shown as a vertical transition between two \(S\) levels, while the 2557 Å line starts from the metastable level \(6^3P_2\) and has an excitation potential of 6.5 volts! The same incorrect diagram is repeated on page 73, already in the text of the book.

The book begins with a list of misprints, next to which is inserted a separate sheet with a corrected figure No. 16 (voltage on the lamp). All this is an obvious trace of the war and the German occupation. There was a shortage of qualified workers. In its content the book represents a fairly standard specimen of “company” literature, although it is not a catalogue in the proper sense of the word.

The entire content of the book is divided into two parts. The first part is small in volume (60 pages) and consists of three chapters. The first chapter contains a very brief and popular exposition of the basic physical questions connected with the principle of operation of the gas-discharge lamp. The second chapter is also devoted to a brief and simple exposition of the principal questions connected with the operation of such auxiliary devices for lamps as rheostats, chokes, transformers, and capacitors. Here the parameters characteristic of this field are given. The third chapter contains a description of the features of electrical circuits containing gas-discharge lamps and the corresponding switching devices. Of special importance, as is well known, is the relation between the supply voltage and the burning voltage of the lamp. The gap between these quantities constitutes one of the main shortcomings of the gas-discharge lamp. The oscillograms of current and voltage in circuits with gas-discharge lamps have a very distinctive appearance. The second part of the book consists of six chapters and is devoted to individual concrete types of gas-discharge lamps manufactured by the Philips firm. Chapter one deals with sodium lamps. Here are described four types of sodium lamps with powers of 45, 60, 85, and 140 watts. The luminous efficacy of the lamps is from 38.5 to 61 lumens per watt for the most powerful type. Data are given characterizing the process of the lamp’s run-up after switching on (the run-up time is from 5 to 10 minutes) and the influence of fluctuations of the mains voltage on the luminous parameters of the lamps. It is shown how the optimum operating regime of the lamp is chosen, and spectral characteristics are presented. Data are given which testify to the improvement of visual function under the light of sodium lamps. The light-distribution curves of the lamps themselves and of fittings with lamps are given. The lifetime of sodium lamps reaches 3000 hours. In the second chapter mercury lamps of high and superhigh pressure with natural cooling are described: high-pressure lamps with powers of 65 and 450 watts and superhigh-pressure lamps of 75 and 120 watts. The luminous efficacy of the lamps is from 35.5 to 42 lumens per watt. Interesting data are given on the temperature distribution over the surface of the outer bulb of the lamp and on the run-up process. There are spectral characteristics and oscillograms of luminous flux, current, and voltage. Further, two types of mixed-light lamps are described in sufficient detail, representing a combination in one bulb of an incandescent lamp and a superhigh-pressure mercury lamp, with powers of 160 and 250 watts and luminous efficacies of 19 and 20 lumens per watt. These lamps have good color characteristics and do not require switching devices. Finally, a description is given of a superhigh-pressure lamp in a bulb coated with phosphor, but, unfortunately, without data on luminous efficacy. Judging from the table on p. 133, the spectral data of such a lamp are not much better than those of an ordinary superhigh-pressure lamp.

Useful data are given on the distribution of brightnesses in all types of mercury lamps and the light-distribution curves of fittings with lamps. The lifetime of the indicated types of lamps is of the order of 2000 hours.

At the end of the chapter relatively new types of lamps are described. These are, above all, powerful ultra-high-pressure lamps—for aerodromes and photocopying. The lamps have powers of 1000 and 2000 watts at a length of about 50 cm. For the 1000-watt lamp the reflector is built in.

Quartz lamps of the “Biosol” type serve as an important source of ultraviolet rays. Detailed data are given on the absolute intensity of the spectral lines emitted by such lamps (in erg/cm²). The third chapter describes ultra-high-pressure mercury lamps with water cooling. It should be noted that, despite the intensive advertising of these lamps by Philips, they cannot be regarded as a technically perfect light source. The power-supply and cooling systems are too complicated, and the service life is too short (100–150 hours). These shortcomings offset both the high brightness (24,000 stilbs) and the high luminous efficacy (up to 63 lumens per watt) of the lamps. The fourth chapter describes the only type of luminescent lamp of low pressure, with a power of 22.5 watts. The luminous efficacy of the lamp is 35.7–41 lumens per watt, depending on the color. The spectral and colorimetric parameters of luminescent lamps are characterized in considerable detail. They are close to the corresponding data for German lamps and are not very high. It is evident that the development of luminescent lamps in Holland was only beginning. In a short fifth chapter, neon lamps and lamps for stroboscopes are very briefly described. For stroboscopes, ultra-high-pressure lamps in a silvered bulb of special shape are used.

At the end of the book there are appendices: designations, a summary of all types of lamps, and an index of the literature.

The bibliography contains only Dutch works.

In assessing the book as a whole, it should be said that it is markedly inferior to Uterhoven’s book of the same name, published in 1938, although it does contain some new data.

In essence, the book under review is something intermediate between a catalogue and a genuine monograph.

V. Fabrikant