Ing. Petr Žák, Ph.D.

Prague, the capital of the Czech Republic, through its representatives, decided on a conceptual and systematic approach to the management of the public lighting. On the basis of this decision, a set of documents was submitted for processing under the title Concept of Prague Public Lighting. This set of documents is intended to specify what the night image of the city should be, creating through public and architectural lighting. When determining the night appearance of the city, not only the safety of the traffic of people and property, but also the undesirable effects of lighting on the surrounding environment and the effect of lighting on the appearance of public spaces should be taken into account. An integral part of the Concept of Prague Public Lighting is also the plan for the renewal and modernization of the public lighting system for the purposes of the city's financial planning. Concept of Prague Public Lighting also contains standards of activity and devices that specify requirements for activities related to public lighting and for products that are part of the public lighting system.

Illuminance meters used for measuring illuminance related to health protection, environmental protection or safety at work are legally controlled measuring instrument in Czech Republic and are subject to Decree of the Ministry of Industry and Trade No. 345/2002 Coll., item 5.1.2 which specifies measuring instruments for mandatory verification and measuring instruments subject to type approval. In the Czech Republic, the legislation defines a period, specified only for legally controlled measuring instrument, that have been type-tested. In the field of illuminance measurement, only a few types of illuminance meters on the market have this type verification. The period of validity of the verification is set by the Decree at 2 years for illuminance meters. The verification legally controlled measuring instrument is carried out by state or authorized testing institutes. Verification by an authorized metrology center confirms that the legally controlled measuring instrument has the required metrological characteristics in accordance with the procedure laid down by the Ministerial Decree, that the selected decisive parameters correspond to the values indicated by the manufacturer and that they meet the requirements of a measure of a general nature issued by the Czech Metrology Institute. For legally controlled measuring instrument, when they are introduced on the market, a type test is required, which is the verification of all the parameters of the instrument according to the type sheets. Only some important parameters are then checked during the actual verification. The legally controlled measuring instrument is marked with an official mark by the authorized metrology center and subsequently receives a verification certificate in accordance with the Ministerial Decree. Where illuminance meters are used in situations where the use of legally controlled measuring instrument is not required, calibration is used for their checking, which is also carried out by an authorized center, such as the Czech Metrology Institute. Calibration does not have a set time interval within the legislation when it is carried out. The calibration period is set by the measuring organizations in their own internal regulations. The voluntary national technical standard specifies a maximum interval between calibrations for field measurement illuminance meters of 3 years. During calibration, the response of the measuring instrument being monitored is determined for a specific standard. The result is a calibration curve from which the 'correct' value relative to a particular standard can be determined. It is clear from the above description that both verification and calibration can be quite time-consuming matters and, due to the financial cost of the test, are normally only undertaken when necessary. Furthermore, it is common for sites to also own indicating instruments without verification or proper calibration. However, even with these devices, it is necessary to verify, at least in a rudimentary way, the correctness of the quantities indicated. Not every workplace is equipped, for example, with a photometric bench where the instruments can be compared and any deviations in the measured values can be determined. This paper describes the design of an instrument used for comparison of illuminance meters, or field verification of the correct functionality of the illuminance meter, correctness of the displayed measurement results and, if necessary, determination of a simplified correction factor of illuminance values for individual illuminance meters. The device is used to ensure that the same amount of light falls on the two detector of the illuminance meters. The measured values are then read from the illuminance meters and the difference is used to determine a simplified correction factor for the illuminance value.

Within the framework of the problematics of undesirable side effects of artificial lighting on the environment, the surroundings are classified in terms of environmental zones. At present, two classifications are used in practice: the earlier system, which contains 4 classes designated as E1 through E4, and the newer one, which contains 5 classes designated as E0 through E4. The earlier classification is used in certain applications of EU technical standards for outdoor lighting, while the newer one is used in the CIE international recommendations. The original delineation of these zones was based on the positions of important astronomical observatories. Currently, the problem of obtrusive light is being addressed with great intensity in from the standpoint of protection of nature and the environment, in other words the influence of artificial light on fauna, flora, and the landscape. In terms of current recommendations for addressing the question of obtrusive light, the delineation of the environmental zones is described quite generally, and there are no clear rules for how to proceed in establishing them in practice.

Currently, the issue of undesirable effects of artificial outdoor lighting on the surrounding environment is a very widely discussed topic. In individual countries, there is an effort to solve this issue within the framework of documents that take different forms, from recommendations to technical standards to legal regulations. Most of these documents are based on the international recommendations of the CIE, which relate to limiting the undesirable effects of so-called obtrusive light on the surrounding environment. In practice, this concept is not widespread among the general public, and is often referred to as light pollution. In spite of the considerable efforts made to address this issue, there is no simple visible consensus in practice on how to deal with it. There are probably several possible reasons. The primary and fundamental one is the issue of terminology and definitions. In practice, one term is used to refer to a number of different phenomena, and at the same time, several terms are used for one phenomenon. Already in current documents, obtrusive light refers to phenomena that are not, by definition, obtrusive light. Clarity and consistency in the use of terms and adherence to their definitions is a prerequisite for mutual understanding when dealing with a particular issue. If definitions are not respected and terminological discipline is not observed, it is very difficult to deal with the issues related to the terms and definitions. The following paper also deals with other possible causes of the mentioned situation.

Quality education in every field is the basis for successful application in practice. A work group for education in lighting technology was established within the Czech Lighting Society, the aim of which is to verify the possibilities of providing education and obtaining certificates of education in this field within Czech legislation and the possibility of cooperation at the international level with ELEA (European Lighting Expert Association).

An integral part of the design and operation of lighting systems is the evaluation and control of lighting parameters at the beginning and during their operation. At present, this evaluation is in most cases narrowed down only to the measurement of illuminance or luminance on the established reference planes. However, the lighting requirements set out in the technical standards are more complex and some parameters are not controlled at all in practice. The paper describes the design of an operational luminance measurement procedure displaying a luminance meter as part of a comprehensive evaluation of lighting systems.

An integral part of the design and operation of lighting systems is the control of lighting parameters at the beginning and during their operation. At present, this evaluation is in the vast majority of cases narrowed down only to the measurement of illuminance, or luminance on the established reference planes. However, the lighting requirements set out in the technical standards are more complex and some parameters are not controlled at all in practice. In current practice, there is a lack of methodological procedures that would describe such an evaluation and on which the professionals would agree. Ambiguities in the evaluation of lighting can be the cause of insufficient control of important lighting parameters and permission of unsuitable lighting, eg in terms of glare or color rendering, and can contribute to requiring controls that are not part of the standards or not meaningful (eg UGR glare index assessment ). The aim of the paper is to open a discussion on the possibility of developing methodological procedures for verifying lighting parameters in practice, which would include the lighting requirements specified in technical standards.

The topic of the obtrusive effects of outdoor lighting on the surrounding environment has gradually permeated public debate and public space, and compared to the recent past, it is one of the most frequently discussed topics. Due to the growing attention and seriousness, this issue is also included in the newly prepared legal regulations in the field of building law, ie the Building Act and subsequent implementing regulations. The newly emerging legislation was one of the main reasons for the establishment of a new technical standardization commission (TNK) within the Czech Agency for Standardization under the name Light pollution - disturbing light.

At the end of last year, in December 2020, the International Electrotechnical Commission (IEC) issued a dictionary in the field of lighting IEC 60050-845 "International Electrotechnical Dictionary - Lighting". This dictionary replaces the ČSN IEC 50 (845) dictionary from and was created in cooperation with the International Commission on Illumination (CIE). It is thematically divided into 12 chapters and contains a total of 1,347 terms and definitions. The paper presents the development of terminology in the field of lighting technology and introduces the organization of terms in the dictionary and the contents of individual chapters.

The paper deals with the measurement of the integral reflectance of diffuse surfaces, which is one of the main input parameters in lighting engineering calculations of indoor and, in some application areas, outdoor lighting systems. Due to the absence of a simple measuring instrument that would allow the measurement of the above parameter, a prototype instrument for measuring the reflectance was designed and an approximate calibration was performed on the reflectance standards in the laboratory of radiometry and photometry of the Czech Metrology Institute.

Last year, a new European standard ČSN EN 17037 Daylighting for buildings was introduced into Czech technical standards. It applies to all areas that can be used regularly by people for a long time, except in cases where the use of daylight is excluded. The new standard defines parameters for the evaluation of daylight, contains principles for the calculation and verification of these parameters, but does not contain the required values of these parameters. It evaluates daylight according to four aspects: the contribution of daylight, the view, the time of sunshine, protection against glare. Thus, although the standard does not contain requirements, it contains recommended values of parameters by which the mentioned aspects are evaluated. Recommended values are given for three levels (minimum, medium, large). Although parameter values are recommended, the standard states that a minimum level of parameters should be ensured.

Looking back, the issue of control and operation of public lighting was relatively clearly and simply described in older technical standards. Each operator should have developed a lighting schedule, taking into account the density of construction, operation and any other parameters. At the same time, the on and off times were also precisely defined, either according to sunset and sunrise, or according to the level of horizontal lighting. Today's technical standards do not define such parameters and the recommended procedures for their determination are complex and unusable in practice. In addition to this uncertainty of current technical standards, light emitting diodes are spreading relatively quickly in public lighting, offering far greater options when choosing types, color properties and control methods. The advent of LEDs is accompanied by new terminology, some terms are unclear and sometimes Czech translations are missing. Along with these topics, another relatively incomprehensible topic appears: Smart City. The mentioned topics contribute to the fact that the area of ​​control and operation of public lighting is unclear and confusing from the point of view of both terminology, possible solutions and technical means. For these reasons, it seems useful to try to clarify the issues related to the control of public lighting.

The paper describes the basic principles of illuminance measurement and possibilities of multi-point measurement of light field spatial properties. Based on the research, the description contains three steps of the development of a multi-point cylindrical illuminance sensor and their hardware architectures. The development aims to create a functional prototype that would allow measurement in addition to one scalar quantity of cylindrical illuminance also the prevailing direction of light in one plane in space, symmetrical, diffuse component, and visual appearance indicator calculated from the ratio of horizontal and cylindrical illuminance.

The paper analyzes the energy intensity of public lighting systems in terms of operating modes and in terms of the luminous efficacy of light emitting diodes (LEDs) used in road luminaires depending on the correlated color temperature, color rendering index and excitation current. In conclusion, the energy performance of selected LED road lights with different parameters (Tcp, Ra) on the model road section is evaluated.

The paper describes a working proposal of a new national methodology for the selection of road lighting classes as a substitute for the methodology given in the standard ČSN CEN / TR 13201-1. The new methodology is based on the administrative division of roads in the Czech Republic introduced in national legislation and its main objective is to simplify the selection of lighting classes in practice and to quickly and efficiently assess the energy performance of public lighting and interfering light.

The paper is focused on the parameters of light field description used to evaluate spatial properties of lighting. These parameters include the vector illuminance, mean illuminance values (spherical, cylindrical, cubic), shape factor and other derived quantities. Their use is mainly for evaluating the quality of lighting systems in terms of subjective perception of sufficient space illumination, but also in terms of visual perception of three-dimensional objects. Based on the theoretical analysis, a prototype sensor was designed for the measurement of mean cylindrical illuminance, which would allow measurement and evaluation of vector properties of light field and derived scalar quantities. The article builds on long-term research in the field of measurement of spatial illuminance characteristics at the Department of Electrical Power Engineering CTU FEE.

The paper provides a detailed analysis of traffic accidents in the Czech Republic, which will serve as one of the input materials for the preparation of the national methodology for the selection of lighting classes for public lighting based on the administrative classification of roads in the Czech Republic. For the analysis of traffic accidents a detailed data of traffic accidents from the statistics of the Police of the Czech Republic in the time period from 2013 to 2017 are used. Traffic accidents are analysed according to the location of the accident, i.e. a straight road section, a road curve, an traffic junction, time interval during the night hours, the road category, the size of the municipality or the severity of the accident. The number of traffic accidents in municipalities during public lighting operation is also compared with the total number of traffic accidents during the day and outside municipalities. The results of the analysis will be used in the selection system of lighting classes for each traffic road category, for setting the parameters in the conflict area and it will be used also for setting rules for adaptive lighting levels during night hours.

The paper contains a detailed analysis of traffic accidents in the Czech Republic, which will serve as one of the input materials for the preparation of the national methodology for the selection of lighting classes for the roads. For the analysis of traffic accidents, detailed data on traffic accidents from the statistics of the Police of the Czech Republic for the period from 2013 to 2017 are used. Traffic accidents are analyzed according to the severity of the traffic accident, the size of the municipality, the category of the road and the time. The number of traffic accidents in municipalities during public lighting operations is also compared with the total number of traffic accidents in the day and outside the municipality.

Looking at the past, the issue of controlling and operating public lighting (VO) in older technical standards has been relatively clearly and simply described and defined. Each operator should have a lighting timetable prepared taking into account building density, traffic and any other parameters. At the same time, the switch-on and switch-off times were either defined according to the sunrise and sunrise with time control, or according to the level of horizontal illumination in the open ground for densely built-up areas or outside of the control room by the photocell. In today's technical standards such parameters are not defined and the recommended procedures for their determination are complex and practically inapplicable. In addition to this uncertainty in current technical standards, light-emitting diodes are expanding relatively rapidly in public lighting, offering far greater choices in the choice of types, color properties, and controls than in the past. The arrival of light diodes is accompanied by a new terminology that is not yet settled, some terms are unclear and sometimes Czech translations are missing. Simultaneously with these topics in the space levitates another relatively unreachable theme: "Smart City". The topics mentioned are that the area of ​​control and operation of public lighting becomes unclear and unclear from the perspective of both terminology, solutions and technical means. For these reasons, it seems useful to try to clarify issues related to the control of public lighting.

The paper describes the proposal for a new methodology for the selection of road lighting classes as a substitute for the methodology stated in ČSN CEN / TR 13201-1. The new methodology is based on the administrative division of roads in the Czech Republic introduced in national legislation and its main objective is to simplify the selection of lighting classes in practice.

Lighting technology is developing very rapidly, especially in the field of light sources and lighting systems control. New semiconductor light sources offer not only new optics design and lighting control but are also accompanied by new terms and definitions that are changing, complementing and refining due to dynamic developments, and it is not entirely clear when and if it will stabilize at all . Due to the continuously expanding technical devices and their application possibilities, as well as the increase of normative documents, the contribution tries to summarize the current situation and to organize and explain the specific terms in specific cases, to facilitate communication and to clarify requirements in the project documentation. At present, some new LED standards already have their Czech design, including the newly introduced terminology.

Artificial lighting and its adoption and use by man has its long history and its reasons and has significantly influenced the development of our society. It is used in a wide range of application areas, such as lighting of sports grounds, roads, or architecture, and its development is accompanied with obtrusive effects. The issue of the obtrusive effects of outdoor lighting is rather extensive and complex and the basis for its solution is to understand the underlying concepts, causes and consequences. The paper describes the development of obtrusive effects of outdoor lighting and basic terminology and some approaches to a possible solution based on international recommendations and national technical standards.

The paper describes a new methodology for the selection of lighting classes in the newly translated standard ČSN CEN / TR 13201-1. It addresses the possibility of creating a new national methodology for the selection of lighting classes based on the administrative division of the roads defined in the national legislation.

The paper describes a new methodology for the selection of lighting classes in the newly translated standard ČSN CEN / TR 13201-1. It addresses the possibility of creating a new national methodology for the selection of lighting classes based on the administrative division of the roads defined in the national legislation.

The paper describes calculation of uncertainty of measurement of luminous intensity distribution of large luminaires at goniophotometer of type 2 with short photometric distance (near field photometry). The short photometric distance causes non-perpendicular incidence of the light coming from the edges of the luminaire onto the photocell of the goniophotometer and thus the measured luminous intensity values could be smaller, than values measured with goniophotometer with adequate photometric distance. The paper should highlight such measurement complication and enlighten operators of goniophotometer of type 2 how to correct measured values of luminous intensity and calculated values of luminous flux of the luminaire.

Modern street lighting represents the pervasive utilization of light-emitting diode (LED) lamps to illuminate urban and rural areas. In addition, LEDbased lighting sources can also be utilized for outdoor data communications and localization. The replacement of traditional street incandescent and fluorescent-based lights by highly efficient LED lights is taking place on a global level. This chapter highlights the main features of LED public lighting systems that could be used for visible light communications (VLC). First, a description of state-of-the-art street lighting, including its main functions, control systems, and typical parameters, is provided. Then the main aspects associated with lighting performance and aging are outlined. The remainder of the chapter is devoted to recent studies on public lighting for VLC purposes, focusing on ray tracing simulations, noise parameters, and delay profiles among other topics.

Public lighting is an important public infrastructure which helps to create the appearance and atmosphere of public spaces of towns and villages. Creating quality public lighting system with adequate operating and investment costs requires a systematic approach. Under such an approach it is necessary to define the quality of public lighting in the broad context, including not only the safety of people, property and transport, energy efficiency, but also architectural and urban aspects and issue of obtrusive light. An essential part of a systematic approach is the description of the activities and subjects that affect the quality and cost of the public lighting. The paper describes one possible approach to systematic solution of public lighting systems.

Perceivable quality and quantity of information on the environment adopted by the human eye is affected by many parameters such as the level of illumination, contrast, luminance, adaptive brightness and spectral properties of light. The main parameters include the degree of glare from light sources, respectively glare rate inhibitions. By 2004, the European countries evaluated glare in essentially two ways: glare index calculation and graphical evaluation of luminance limitat lines. Since 2004, the unification and methodology currently used method of "Unified glare rating" (UGR). The basis of this method is the formula for calculating the glare index UGR, from which are derived the tabular method and the luminance limit lines. In practice, it is customary to evaluate the glare by calculation using the formula. To control glare rating with UGR method is more practical and faster tabular method, which is rarely used in practice. The article is devoted to using the tabulation method UGR.

Perceivable quality and quantity of information on the environment adopted by the human eye is affected by many parameters such as the level of illumination, contrast, luminance, adaptive brightness and spectral properties of light. The main parameters include the degree of glare from light sources, respectively glare rate inhibitions. By 2004, the European countries evaluated glare in essentially two ways: glare index calculation and graphical evaluation of luminance limitat lines. Since 2004, the unification and methodology currently used method of "Unified glare rating" (UGR). The basis of this method is the formula for calculating the glare index UGR, from which are derived the tabular method and the luminance limit lines. In practice, it is customary to evaluate the glare by calculation using the formula. To control glare rating with UGR method is more practical and faster tabular method, which is rarely used in practice. The article is devoted to using the tabulation method UGR.

Lighting design with the advent of computer technology has changed markedly. On the one hand, computer technology made it possible to model complex spaces and lighting systems quickly to verify the behavior of light in space. On the other hand there has been a shift away from simple manual methods associated with the basic principles of lighting. Using manual methods of calculation allow close contact with the basic principles of lighting and the quick view at a problem. Such lack of knowledge of basic principles affects the quality of lighting design. The paper describes the basic principles of lighting values and their influence on the calculations of light technical parameters.

At the end of last year the European standards for street lighting EN 13201 has been updated at the level of European standards committee. In late June this set was also incorporated into the system of Czech technical standards. The paper is devoted to substantial changes that have occurred in the new standards and changes of the previous version of technical standard.

At the end of last year the European standards for street lighting EN 13201 has been updated at the level of European standards committee. In late June this set was also incorporated into the system of Czech technical standards. The paper is devoted to substantial changes that have occurred in the new standards and changes of the previous version of technical standard.

Human visual perception in terms of spectral properties of light is influenced by three basic components, which are the light source and its spectral distribution of the radiant power, observed object and its spectral properties of surfaces and human eye and its spectral sensitivity. The resultant visual perception is influenced by the interaction of these three components. In the case of street lighting, where the spectral sensitivity of the human eye is changing and where the light sources with very different spectral distribution are used, the real perception is significantly influenced by the choice of light source. The paper describes the influence of different light sources on the visual perception in terms of street lighting.

Public lighting as well as every technical infrastructure has got its own lifetime, so the periodic renovation is needed. Public lighting in the Czech Republic was built during the 70´s of the last century and regular renovations were done only in larger cities. In small cities and villages, the public lighting systems are almost at the end of their life time and it is necessary to make the overall reconstruction. For a long time, relatively a little attention was paid to public lighting. The situation was changed in the last few years, where thanks to the pressure to lower the energy consumption, the attention was focused also on the public lighting. Solutions of problems with energy efficiency are usually accompanied by financial instruments in the form of subsidies, grants etc. which support the change of technical equipment with low efficiency for technical equipment with high efficiency. However, in above mention steps the considerations of the overall reconstruction of public lighting is missing. With reference to situation in public lighting systems it would be appropriate to combine their energy performance solutions with overall reconstruction. Older lighting systems and unfortunately, also some new lighting systems, are not only energy inefficient but in many cases they also visually disturb public spaces by their location, design or proportions. In addition, they are the sources of obtrusive light too. Public spaces are important part of human settlements and the scale of life quality. The light is an instrument for creating environment with regards to many aspects (cultural, historical, functional, etc.) of urban areas. It is necessary to perceive public lighting comprehensively taking into account not only the traffic safety and energy consumption but also architectural-urban aspects and aspects connected with minimizing of obtrusive light.

Paper deals with problematic of evaluation artificial and daylight as one medium. By this assumption we have to deal with the different evaluation of each lighting system. Whereas artificial light is evaluated by the measured or calculated value of illuminance stated in lux, daylight is evaluated by the value of daylight factor expressed in %. In paper is discussed the example of the possible lighting calculation by using the light vector to define illuminance in the field of rectangular light source such as window, problematic of various conditions of daylight and possible using of this method.

Current method of design and evaluation of interior lighting in buildings is pulverized to the solution of individual spaces. Separately is evaluated energy consumption for lighting in the building. In this situation is very difficult to optimize the lighting systems. The relationship between the needs for lighting and overall energy consumption for lighting is not obvious. Clearer connection can be found in the simplified view of the whole issue. The required lighting levels and thus energy consumption in buildings are affected by three basic aspects. The first aspect is the usage of the building, i.e. what types of visual tasks in a building are exercised. The basic parameter for quantitative evaluation of visual requirements in today's practice is the illuminance E (Ix). The second aspect is the size of the building, thus the dimensions of spaces in which the visual tasks are performed. In this case the basic parameter is the illuminated area A (m2). The last aspect is the time during which the visual tasks are performed, expressed by operating time T (h). In this view the issue of the interior lighting in buildings can be converted to the delivery of luminous flux Φ (lm) or quantity of light QV (lm.h / year). Such expression is conceptually close to requirements for the supply of other media to the buildings, such as heat, air, water etc. The above considerations set the desired amount of luminous flux, respectively quantity of light. The next step is to set lighting quality parameters such as a minimum proportion of daylight, uniformity, limitation of the glare, the colour properties of light. In the last step, the optimal technical solution is found by selecting the type of lighting systems, light sources and luminaires, which meets both quantitative and qualitative requirements of lighting. Such approaches allow the creation of ideas about lighting needs in the initial stages of project and convert them to specific technical solutions.

Interior lighting is in the project documentation solved in two separate parts. The architectural part solves daylighting system and the electrical part solves the level of artificial light and lighting control. Proposal for both types of lighting systems is based on two different approaches. The newly proposed methodology understands light as one of the media necessary for the operation of buildings, associated with both hygienic and energy aspects of the project with the interior.

Interior lighting design within the project documentation is stated in two separate sections. At the structural and architectural part of documentation day lighting and energy performance of lighting is solved. At the part of electrical set the artificial lighting and lighting control is solved. Lighting parameters are covering two different aspects. The hygiene aspect is evaluated by the level of lighting Em (lx) and the daylight contribution D (%). Energy performance is evaluated by LENI (kWh.m-2/year). Comprehensive and effective solution of the interior lighting is complicated by the solution in two parts of the project documentation and by using incompatible parameters for the evaluation. The newly proposed method is trying to see the light as a medium necessary for the building operation, which is connected with health, safety and visual comfort of the observers as well as with energy performance of the building.

In last few years, public lighting begins to pay more attention. The probable reason for this increased interest can be either a physical state of lighting, a chance to get grants and possible sfunds avings in the municipal budget. The fact that many public lighting systems, especially in smaller municipalities, are at the end of the life together with new technical means on the market give a chance to build a new, modern lighting, which would create the appropriate atmosphere corresponding to the night spot, while ensuring the security needed for transport, persons and property, while limiting obtrusive light, with minimal power consumption and saving costs for lighting systems.

The first part of paper presents the results of research of the influence of spectral properties of light sources in public lighting. The second part describes in more detail a real eye vision and interaction between the spectral characteristics of light sources, properties of reflective surfaces and the human eye.

Energy performance of a building control systems are two current issues affecting also the area of lighting. The current design practice hints with regard to the above-mentioned topics, to its limits. Interior lighting is a part of the project documentation addressed in two separate sections. The architecture of the building is solving daylight and energy intensity of illumination and in the electrical equipment deals with artificial lighting. The newly proposed methodology seeks to understand light as one of the media necessary for the operation of buildings that are related to health, safety and visual comfort, and with the energy performance of buildings.

The article presents results of applying the newly proposed system for mesopic photometry based on visual performance in practical conditions in the area of public lighting. For a group of nine lamps with different spectral composition was made the analysis of the luminous flux changes, that occur due to the changes in the spectral sensitivity of the human eye in mesopic conditions.

The book is devoted to the current lighting technology with a focus on the basics of lighting. The opening section of publication focuses on topics of optical radiation and physiology of the visual system, explaining the basic photometric terms, quantities and units, as well as photometric measurement principles and basics of colorimetry. The second section of the book focuses on light sources including electrodeless lamps and light emitting diodes (LED ) and their ballasts. The following chapters are about luminaires, their basic components and parameters . The reader will find solution concepts and new types of lights for LEDs. The fourth part of the publication discusses the principles of lighting, lighting systems for indoor and outdoor spaces, including the calculation of system parameters and evaluate their energy performance. The final section of the book presents the principles and basic rules for the design of electrical installations, approaching the issue of command and control of lighting systems . This information is supplemented by an overview of the most important standards in the field of lighting technology and there is a foreign language glossaries of key terms. The book is intended for lighting engineers, architects, designers, indoor and outdoor lighting system operators, students of electrical engineering and construction industries, as well as for courses focused on building control.

Energy demand and building control systems are two actual topical issues, which affect also the field of lighting technology. Current design practice hints with regards to the above mentioned topics on their borders. Indoor lighting as part of the project documentation is addressed it two separate sections. In civil engineering and architectural part daylighting is solved and in high voltage electrical devices the artificial lighting is solved. Design and evaluation of both types of lighting systems is based on two different approaches. Daylighing is designed and evaluated by using of daylight factor Dm, artificial lighting is designed and evaluated by maintained illuminance Em. For this reason proposals for both lighting systems is largely incompatible. The newly proposed concept seeks to understand light as one media necessary for operation of buildings that relate to the health, safety and performance of their users, and with energy consumption of a building.

The main technical parameters on which are today considered light sources and their development, are luminous efficacy, lifetime and quality of color rendering. For conventional light sources are capable of new light sources compete primarily fluorescent and halogen lamps. In the long run, however, cannot be excluded that lighting parameters and these light sources will be overcome by new, whether electrodeless or semiconductor, light sources. Light sources, especially the group of semiconductor light sources, are today the fastest growing areas of lighting technology and its development significantly affects the situation on the market of luminaires.

Jednou z aplikačních oblastí ve venkovním osvětlení je veřejné osvětlení. Jednou z možných cest hledání energetických úspor v této oblasti je pokusit se nalézt úspory ve vzájemně koordinovaném využití veřejného a automobilového osvětlení. Osvětlení automobilů musí být navrženo tak, aby zajistilo dostatečné osvětlení povrchu vozovky jak ve městech, tak mimo město, tedy pro případy, kdy není k dispozici veřejné osvětlení. Veřejné osvětlení se pak navrhuje v zastavěných částech měst a obcí, bez ohledu na automobilové osvětlení. Vyvstává zde otázka, zda by nebylo možné provést optimalizaci osvětlení pozemních komunikací a automobilového osvětlení z pohledu energetické náročnosti. Pro hledání odpovědi na tuto otázku je třeba nejprve popsat, jak se oba systémy fungují, jakými kritérii se posuzují a jakými veličinami se hodnotí.

The creating of the visual comfort depends not only on the good choosing of the lighting group, lamps and coloring of the surfage, but it is connected with the total facilities of the indoor microenvironment and the total human condition.

An important aspect in the development of any discipline, including lighting engineering, is its place in and its importance for society in general. They fundamentally influence the quality, extent, and speed of implementing new ideas and innovations in the field, and how these new ideas are received by professionals as well as non-professionals. Apart from its place in society, the future of lighting engineering is determined by other developments which take place in various, often unrelated areas such as technical resources, research in the area of visual perception, new approaches in lighting design or the impact of light on the environment.

An important characteristic of our time is very fast development of technological processes, influencing the speed of implementation of research and development into routine practice. The rate of development of new products in the field of lighting technology provides important technical information from a simple marketing description. The market is flooded with a large number of products that customers are not ready to meet, and where the lack of information that would allow to assess whether a given product for a particular type of use is appropriate. Post provides information about the current situation in the field of semiconductor light sources and compares the technical specifications for LED lighting and conventional light sources in selected application areas.

For a number of years, the attention has been drawn to the issue of energy saving not only in the field of lighting, but also in many other areas. A crucial moment in the process of dealing with this issue was the opening of the discussions on global warming. One of the effects of this discussion is that the pressure on a fast introduction of new technologies, procedures and new legislation, which would result in reducing energy performance of outdoor as well as indoor lighting systems, has been increasing. This paper deals with the relationship between the technical parameters of illumination and the energy performance of lighting and describes possible trends in achieving energy efficient lighting systems.

An important aspect for the development of any field of human activity, including lighting technology is its importance and position in society. It fundamentally affects the quality, range and speed of application of new ideas and innovations that are emerging in the field and acceptation of innovations by public people and professionals. The future of lighting technology, in addition to the position in society determined by the development, which is characterized by wide range of this field and by various, often very different, areas such as the field of technical resources, research on visual perception, new approaches in the design of lighting or the influence of light on the surrounding environment.

Nowadays the area of light sources is one of the most dynamically evolving areas significantly influencing the situation of the luminaire market. New production technologies and procedures, high efficient production organization and fast information exchange are making it possible to send new types of light sources into mass production after very short intervals, at the present time being 6 to 12 months. This forces manufacturers of luminaires to shorten the till today common 2 year research, development and production cycle of new luminaire types.

There is nowadays on many levels an often discussed question: energy demandingness of various types of buildings such as administrative, industrial, medical, educational, etc. A part of this problem is also the solution of the energy demandingness of lighting systems of the given buildings. The base considering this problem is the newly conseived norm ČSN EN 15 193 Energy demandingness of buildings - Energy requirements of lighting and a technical standars information TNI 73 0327.

For many years, attention has been paid to the energy conservation issues, not only in the area of lighting but also in a number of other fields. Launching a discussion about global warming meant a significant moment of this issue´s solution process. One of the consequences of this discussion is the increasing pressure to accelerate the introduction of new technologies, procedures as well as legislation, which all lead to reducing of energy demandingness in outdoor and indoor lighting systems. The report is dedicated to the relationship between technical parameters and energetic demandingness of the lighting and describes possible directions in search of energetically efficient lighting systems.

There is nowadays on many levels an often discussed question: energy demandingness of various types of buildings such as administrative, industrial, medical, educational, etc. A part of this problem is also the solution of the energy demandingness of lighting systems of the given buildings. The base considering this problem is the newly conseived norm ČSN EN 15 193 Energy demandingness of buildings - Energy requirements of lighting and a technical standars information TNI 73 0327.

Public lighting is now entering into a new era in which a lot of changes can be expected. Design and public lighting system solutions will be more and more influenced by both new technical equipments, changes in legislation and by new conceptual approaches. The impulse for these changes will be not only the very fast development in the area of new lighting sources, optic systems and luminaires, but also the ways of power supply, control and regulation of the lighting systems. The results of research in the field of visual performance in mesopic vision will have no less important impact. New approaches to public lighting system solutions will represent significant changes not only in the quality of illumination, energy demandingness and elimination of public lighting side effects, but also in the general appearance of the nocturnal environment of municipalities.

The paper deals with possibilities of evaluation of lighting systems quality not only in terms of normative, but also in terms of visual comfort while reducing the energy intensity of the lighting systems. There are described potentials to reduce energy intensity of the lighting system by suitable choice of lighting systems, using the daylighting and using various technical means, such as checking the presence of people within the area, the introduction of time-lighting systems, etc.

In many papers and talks on the topic "The perspectives of the lighting technology" is talked mainly about the developement in the range of the lighting devices (lighting sources, luminaires etc.), but is forgotten about the developement in own lighting design. Nevertheless, the developement in this field influences in principal way the state and next developement in the lighting technology. The paper tries to describe the possible development in the understanding and perception of the lighting from different views and in different connections, tries to name the present trends in this field, to sketch the possible philosophical view of the lighting a to describe the lighting design procedure from the general idea to the concrete lighting system.