**1. Introduction**

According to the estimates of the International Energy Agency (IEA), almost a fifth of all consumed electricity in the world is spent on lighting. One way to reduce the proportion of consumed electricity and its economical expenditure is the development of new energy-efficient light sources and lighting devices based on them. Requirements for such light sources are

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

dictated by market demands, as well as the development and capabilities of modern technologies. Modern light sources must satisfy a number of parameters, combining high light output and efficiency with the comfort of perceiving generated radiation by the eye (a wide spectrum of radiation and color rendering), durability and environmental friendliness with low cost and a wide range of applications.

were conducted in Europe by Plasma International Group [2]. In 2010, the lighting system AS1300 was presented, consisting of a power supply, a microwave generator (magnetron) and the light module. However, their production was complicated by the complexity of the

Microwave Energy and Light Energy Transformation: Methods, Schemes and Designs

http://dx.doi.org/10.5772/intechopen.73755

77

Recently, there have been designs of relatively low-power plasma lighting devices based on light emitting plasma (LEP) lamps with power from ~160 W to 300–400 W, in which solid-state microwave generators are used as an electromagnetic field source [3]. Now, the scope of such lamps is growing: from architectural lighting and street lighting to their application in the

The peculiarity of the topic of plasma light sources with microwave excitation is the long and constant interest to them (more than 25 years), which is expressed in a great number of scientific publications, including monographs, articles, patents obtained in different countries of the world. What is the heightened interest to the lighting systems based on plasma lamps with microwave excitation in? The answer to this question lies in the unique combination of their technical and lighting characteristics and parameters that most fully meet the requirements for light sources formulated above. For example, light generated by these lamps is characterized by high light flux (120–145 klm), light intensity (~9000 cd) and brightness, as well as good light output (80–110 Lm/W). Technical parameters of lighting devices based on plasma light sources with microwave excitation are characterized by relatively low power consumption, a continuous spectrum close to natural (solar) illumination with a color coefficient *<sup>R</sup> <sup>a</sup>* <sup>&</sup>gt; 90 (with a maximum value of 100) and the ability to control the intensity of light. An important advantage is also their environmental friendliness, which is due to the lack of mercury and the use of environmentally friendly materials—argon and

Among the problems that need to be addressed, we should note the insufficiently long service life of magnetrons and the uneven heating of the surface of the lamp bulb, which requires to provide its rotation in the cavity space as well as studies aimed at selecting new materials. This will increase the durability of the lamp, which today does not exceed ~50 thousand

This chapter is organized in five main sections. Section 1 describes the construction of a lighting device based on an electrodeless sulfur lamp with microwave excitation, gives a brief characteristic of its main components and analyzes their operation parameters. Section 2 considers an application of the electrodeless sulfur lamps with microwave excitation as the simulators of solar radiation, gives the comparative characteristics of such lamps with other lighting sources. Section 3 concerns promising directions for practical application of a lighting installation based on an electrodeless sulfur lamp with microwave excitation, in particular, for using in greenhouses. Section 4 presents the construction of the lighting system with the possibility of regenerating the energy of optical radiation into direct current energy for increasing its full efficiency. The main conclusions

design and the high cost of the lighting device.

automobile industry.

sulfur.

hours.

are formulated in Section 5.

It is known that the problem of lighting is being solved by converting electrical energy into optical energy (visible light) with the help of various media and the processes occurring in them: metals and thermal processes (incandescent lamps (IL)), gaseous media and discharge (including plasma) phenomena (fluorescent (FL) and metal halide (MHL) lamps, etc.), as well as semiconductor materials and processes of spontaneous recombination of injected minority carriers (light-emitting diodes (LEDs)). Comparative efficiency of existing light sources is shown in **Figure 1**. It can be seen that the heat sources of light (incandescent lamps) in view of their low efficiency (only 3% of the supplied electric energy is converted into the energy of light waves) are much inferior to discharge lamps and LEDs.

Among the existing promising sources of light, special attention is paid to the development of plasma lighting devices based on the use of an electrodeless sulfur lamp with microwave excitation (ESLME). For the first time, such kind of lamp was presented in 1992 at the VI International Symposium on the Science and Technology of Light Sources in Budapest [1]. Later, based on it, Fusion Lighting Co. company created the lighting system Solar 1000 (1994), as well as its modification Light-drive 1000 (1997). Significant efforts to expand the use of these lamps were made by the Korean company LG Electronics, which, in 2005, held a presentation of the plasma lamp Plasma Lighting System (PLS), and also organized a series production of a number of designs of such light sources in the form of a ceiling lamp and spotlight lamp. In parallel, studies of electrodeless sulfur lamp with microwave excitation

**Figure 1.** Evaluation of the effectiveness of light sources.

were conducted in Europe by Plasma International Group [2]. In 2010, the lighting system AS1300 was presented, consisting of a power supply, a microwave generator (magnetron) and the light module. However, their production was complicated by the complexity of the design and the high cost of the lighting device.

dictated by market demands, as well as the development and capabilities of modern technologies. Modern light sources must satisfy a number of parameters, combining high light output and efficiency with the comfort of perceiving generated radiation by the eye (a wide spectrum of radiation and color rendering), durability and environmental friendliness with low cost

It is known that the problem of lighting is being solved by converting electrical energy into optical energy (visible light) with the help of various media and the processes occurring in them: metals and thermal processes (incandescent lamps (IL)), gaseous media and discharge (including plasma) phenomena (fluorescent (FL) and metal halide (MHL) lamps, etc.), as well as semiconductor materials and processes of spontaneous recombination of injected minority carriers (light-emitting diodes (LEDs)). Comparative efficiency of existing light sources is shown in **Figure 1**. It can be seen that the heat sources of light (incandescent lamps) in view of their low efficiency (only 3% of the supplied electric energy is converted into the energy of

Among the existing promising sources of light, special attention is paid to the development of plasma lighting devices based on the use of an electrodeless sulfur lamp with microwave excitation (ESLME). For the first time, such kind of lamp was presented in 1992 at the VI International Symposium on the Science and Technology of Light Sources in Budapest [1]. Later, based on it, Fusion Lighting Co. company created the lighting system Solar 1000 (1994), as well as its modification Light-drive 1000 (1997). Significant efforts to expand the use of these lamps were made by the Korean company LG Electronics, which, in 2005, held a presentation of the plasma lamp Plasma Lighting System (PLS), and also organized a series production of a number of designs of such light sources in the form of a ceiling lamp and spotlight lamp. In parallel, studies of electrodeless sulfur lamp with microwave excitation

and a wide range of applications.

light waves) are much inferior to discharge lamps and LEDs.

76 Emerging Microwave Technologies in Industrial, Agricultural, Medical and Food Processing

**Figure 1.** Evaluation of the effectiveness of light sources.

Recently, there have been designs of relatively low-power plasma lighting devices based on light emitting plasma (LEP) lamps with power from ~160 W to 300–400 W, in which solid-state microwave generators are used as an electromagnetic field source [3]. Now, the scope of such lamps is growing: from architectural lighting and street lighting to their application in the automobile industry.

The peculiarity of the topic of plasma light sources with microwave excitation is the long and constant interest to them (more than 25 years), which is expressed in a great number of scientific publications, including monographs, articles, patents obtained in different countries of the world. What is the heightened interest to the lighting systems based on plasma lamps with microwave excitation in? The answer to this question lies in the unique combination of their technical and lighting characteristics and parameters that most fully meet the requirements for light sources formulated above. For example, light generated by these lamps is characterized by high light flux (120–145 klm), light intensity (~9000 cd) and brightness, as well as good light output (80–110 Lm/W). Technical parameters of lighting devices based on plasma light sources with microwave excitation are characterized by relatively low power consumption, a continuous spectrum close to natural (solar) illumination with a color coefficient *<sup>R</sup> <sup>a</sup>* <sup>&</sup>gt; 90 (with a maximum value of 100) and the ability to control the intensity of light. An important advantage is also their environmental friendliness, which is due to the lack of mercury and the use of environmentally friendly materials—argon and sulfur.

Among the problems that need to be addressed, we should note the insufficiently long service life of magnetrons and the uneven heating of the surface of the lamp bulb, which requires to provide its rotation in the cavity space as well as studies aimed at selecting new materials. This will increase the durability of the lamp, which today does not exceed ~50 thousand hours.

This chapter is organized in five main sections. Section 1 describes the construction of a lighting device based on an electrodeless sulfur lamp with microwave excitation, gives a brief characteristic of its main components and analyzes their operation parameters. Section 2 considers an application of the electrodeless sulfur lamps with microwave excitation as the simulators of solar radiation, gives the comparative characteristics of such lamps with other lighting sources. Section 3 concerns promising directions for practical application of a lighting installation based on an electrodeless sulfur lamp with microwave excitation, in particular, for using in greenhouses. Section 4 presents the construction of the lighting system with the possibility of regenerating the energy of optical radiation into direct current energy for increasing its full efficiency. The main conclusions are formulated in Section 5.
