Luminous Flux Values Research Articles

Laser light illuminant based on YAG: Ce phosphor ceramic with ultra-high luminance, stable output, and excellent heat dissipation

A hundred-watt level blue collimated laser is used to excite YAG: Ce phosphor ceramics to prepare a high-power white laser-based illuminant. A composite ceramic cooling device is prepared to reduce the operating temperature of YAG: Ce phosphor ceramics by using nano-silver to weld ceramics onto a copper block with a water-cooling device. Phosphor ceramics encapsulated with the above device can withstand the excitation of a 123W blue laser, and its output luminous flux value reaches 14600lm. The stable output time of the laser-based illuminant is over 30 minutes, and the operating temperature of the phosphor ceramic surface is only 270°C. Compared with the non-cooling device package, the luminous flux of the laser-based illuminant composed of phosphor ceramics packaged with the above structure is increased by 252.8%. The experimental results show that the composite ceramic cooling device can effectively reduce the operating temperature of phosphor ceramics which is an effective way to realize white laser-based illuminants over 10000lm.

Uncertainty analysis of spectral flux measurement using Monte Carlo simulation

In photometry, spectrally integrated quantities are commonly used, and their uncertainties are calculated using classical approaches. Since determining correlations at different wavelengths and effects on spectrally integrated quantities is rather complex, a noise modification of the spectral value using Monte Carlo simulation was applied to estimate unknown correlations in the uncertainty of total luminous flux based on integrated spectral luminous flux values. For this aim, an LED with 6500 K correlated colour temperature was measured in an integrated sphere flux measurement system. The correlations between the measurements at different wavelengths were analysed, and the uncertainty boundaries of the integrated quantity and total luminous flux were obtained.

The use of CaO:Eu<sup>3+</sup> and Zn<sub>2</sub>SiO<sub>4</sub>:Mn<sup>2+</sup> phosphors to increase the color quality and illumination intensity of WLEDs

The lumen efficacy in remote phosphor structure displayed remarkable enhancements, which is notable for the development of white light-emitting diodes (WLEDs). Nevertheless, its quality of colour is deemed not as good as that of the conformal or in-cup phosphor structure. Therefore, the goal of this research is to achieve a better quality of colour and significant luminous flux value for remote phosphor configuration by using extra phosphor layers. In particular, the two-layer and three-layer structures with the implementation of green and red phosphors are proposed. Comparing these two structures can help pinpoint the best suited for the WLED production. The assessment of each structure’s effect on the WLEDs’ optical parameters was determined under various correlated temperatures of colour (5,600-8,500 K). The outcomes indicated that the three-layer structure enhanced the quality of colour with greater efficiency compared to the two-layer structure due to the increased color rendering index (CRI), color quality scale (CQS), and photoluminescence (PL), and reduced colour deviation. The scattering improvement of the three-layer structure is a key factor of these accomplishments, proven by the scattering theory of Mie. Therefore, the three-layer structure is potential for developing WLED production.

The Spotlight Based on the Solid-State Laser Light Source

The spotlight development on the solid-state laser light source is considered in this scientific article. The light sources characteristics are as close as possible to the characteristics and parameters of modern LED light sources. The main aim is to reach the luminous flux value of 3000 lm. That is analogues with the luminous flux of modern LED searchlights. As well as the photometric and electrical parameters, values and determination of the measures to improve the design of the spotlight are of the interest. The spotlight sample has been tested. And the test results show that after the value of 3000 lm reached the main failing of light source is the low value of its luminous efficacy, equal to 57 lm/W. In order to increase the light output of the searchlight, there are the ways of modernization of its construction suggested in the article. The previous results show that the measures suggested will allow us to increase the value of luminous efficacy to 100 lm/W. Besides that, such parameters and characteristics of the spotlight as the correlated colour temperature (CCT), colour rendering index (CRI), wattage, luminous intensity and spectral light distribution are measured and submitted in the article. The obtained energetic characteristics of the sample allow us to conclude that application of such light sources is approved in special conditions. Absence of electronic components in the distant radiation source of white light allows increasing the light source reliability substantially. Therefore, the laser spotlights are acceptable for application in the hard-to-reach places for installation of the lighting equipment, for example, on high places where the equipment demount used for repairing works is too difficult. It is actually to use also the developed light sources at the explosive industrial facilities having the current-transmitting elements of construction, especially having the open contacts. That allows reducing the safety of facility operation significantly.

CVD processed ZnO thin film as solid thermal interface material in electronic devices: thermal and optical performance of LED

Purpose Polymer-based thermal interface materials (TIMs) are having pump out problem and could be resolved for reliable application. Solid-based interface materials have been suggested and reported. The purpose of this paper is suggesting thin film-based TIM to sustain the light-emiting diode (LED) performance and electronic device miniaturization. Design/methodology/approach Consequently, ZnO thin film at various thicknesses was prepared by chemical vapour deposition (CVD) method and tested their thermal behaviour using thermal transient analysis as solid TIM for high-power LED. Findings Low value in total thermal resistance (Rth-tot) was observed for ZnO thin film boundary condition than bare Al boundary condition. The measured interface (ZnO thin film) resistance {(Rth-bhs) thermal resistance of the interface layer (thin film) placed between metal core printed circuit board (MCPCB) board and Al substrates} was nearly equal to Ag paste boundary condition and showed low values for ZnO film prepared at 30 min process time measured at 700 mA. The TJ value of LED mounted on ZnO thin film (prepared at 30 min.) coated Al substrates was measured to be 74.8°C. High value in junction temperature difference (ΔTJ) of about 4.7°C was noticed with 30 min processed ZnO thin film when compared with Al boundary condition. Low correlated colour temperature and high luminous flux values of tested LED were also observed with ZnO thin film boundary condition (processed at 30 min) compared with both Al substrate and Ag paste boundary condition. Originality/value Overall, 30 min CVD processed ZnO thin film would be an alternative for commercial TIM to achieve efficient thermal management. This will increase the life span of the LED as the proposed material decreases the TJ values.

Porous Ce:YAG ceramics with controllable microstructure for high‐brightness laser lighting

AbstractIn order to meet the increasing demand for high‐power laser diode lighting and displays, phosphor converters with high‐brightness and high‐directionality ought to be constructed to enhance the luminance and luminous efficacy. However, the pores formed during the sintering of phosphor ceramics affect the scattering effect and directionality of light. Therefore, porosity optimization and pore size regulation need to be explored. In this work, a series of Ce:YAG ceramics with various porosities and pore sizes were prepared. The influences of porosity and pore size on the microstructure, light confinement ability, and optical properties of Ce:YAG ceramics were studied. The ceramic phosphor with a porosity of 10 vol.% and a pore size of 3 μm exhibits a good spot confinement ability and shows a high luminous flux value of 3430 lm and a central luminance (1669 592 cd/m2) under blue laser excitation. The 10 vol.% Ce:YAG ceramic phosphor with a pore size of 5 μm has the highest emission intensity and gives a maximum luminous efficacy of 268 lm/W and a luminous flux of 4020 lm under 30 W/mm2 blue laser excitation. Thus, the porous Ce:YAG ceramics are expected to be a promising candidate for high‐brightness laser lighting and projection applications.

Tunnel Illumination: Algorithm to Determine Standard Values of Luminance in Tunnel Zones Using C Programming Language Approach

Tunnel illumination design involves complex mathematical computation, cumbersome, and tedious to perform when done by hand. This paper proposes an algorithm to compute luminance and luminous flux of the different zones of the tunnel by following the International Commission on Illumination (CIE88:2004) standard design guidelines using the C programming language. The luminance and the luminous flux values of all the zones were calculated and compared with the CIE standard. The energy consumption of each zone is equally found to control and reduce energy wastage and payment of unwanted bills. The threshold zone length Lth, average luminance in the first half Lav, and the last half of the threshold zone are 40 m, 400 cd/m2, and 240 cd/m2, respectively, while the average luminance of the transition and interior zones are, respectively, 95.87 cd/m2 and 5.86 cd/m2. The results obtained were satisfying. The computational results showed that the proposed Algorithm could be used to design an efficient tunnel illumination system with less energy waste.

Impact of thermal interface material on luminous flux curve of InGaAlP low-power light-emitting diodes

Purpose One major problem in the lighting industry is the thermal management of the devices. Handling of thermal resistance from solder point to the ambiance of the light-emitting diode (LED) package is linked to the external thermal management that includes a selection of the cooling mode, design of heatsink/substrate and thermal interface material (TIM). Among the significant factors that increase the light output of the of the LED system are efficient substrate and TIM. In this work, the influence of TIM on the luminous flux performance of commercial indium gallium aluminium phosphide (InGaAlP) low-power (LP) LEDs was investigated. Design/methodology/approach One batch of LEDs was mounted directly onto substrates which were glass-reinforced epoxy (FR4) and aluminium-based metal-core printed circuit boards (MCPCBs) with a dielectric layer of different thermal conductivities. Another batch of LEDs was prepared in a similar way, but a layer of TIM was embedded between the LED package and substrate. The TIMs were thermally conductive epoxy (TCE) and thermally conductive adhesive (TCA). The LED parameters were measured by using the integrated system of thermal transient tester (T3Ster) and thermal-radiometric characterization of LEDs at various input currents. Findings With the employment of TIM, the authors found that the LED’s maximum luminous flux was significantly higher than the value mentioned in the LED datasheet, and that a significant reduction in thermal resistance and junction temperature was revealed. The results showed that for a system with low thermal resistance, the maximum luminous flux appeared to occur at a higher power level. It was found that the maximum luminous flux was 24.10, 28.40 and 36.00 lm for the LEDs mounted on the FR4 and two MCPCBs, respectively. After TCA application on the LEDs, the maximum luminous flux values were 32.70, 36.60 and 37.60 lm for the FR4 and MCPCBs, respectively. Moreover, the findings demonstrated that the performance of the LED mounted on the FR4 substrate was more affected by the employment of the TIM than that of MCPCBs. Research limitations/implications One of the major problems in the lighting industry is the thermal management of the device. In many low-power LED applications, the air gap between the two solder pads is not filled up. Heat flow is restricted by the air gap leading to thermal build-up and higher thermal resistance resulting in lower maximum luminous flux. Among the significant factors that increase the light output of the LED system are efficient substrate and TIM. Practical implications The findings in this work can be used as a method to improve thermal management of LP LEDs by applying thermal interface materials that can offer more efficient and brighter LP LEDs. Using aluminium-based substrates can also offer similar benefits. Social implications Users of LP LEDs can benefit from the findings in this work. Brighter automotive lighting (signalling and backlighting) can be achieved, and better automotive lighting can offer better safety for the people on the street, especially during raining and foggy weather. User can also use a lower LED power rating to achieve similar brightness level with LED with higher power rating. Originality/value Better thermal management of commercial LP LEDs was achieved with the employment of thermal interface materials resulting in lower thermal resistance, lower junction temperature and brighter LEDs.

Assessment of photometric and electrical measurements of residential light sources

The development of light sources that provides lighting with electrical energy has a history of about 200 years and it has still been continuing today. Over the time, different light sources have been developed by the use of different technologies. Eventually, a large product inventory comprised from light sources in different structures and characteristics has been obtained. Residential lighting is an important field in the sector in terms of appealing large number of users and a wide range of application areas. In addition, lighting quality is prioritized in residential buildings, because people get more closely exposed to artificial light in those places. In this study, the most commonly used eight different light sources in residential buildings have been investigated. The selected light sources are comprised of the products from halogen, CFL and LED lighting technologies. All the light sources have been chosen with equivalent luminous flux values. The selected light sources have been subjected to photometric and electrical measurements realized simultaneously under the same ambient conditions. The interactions between photometric parameters and the meaning of these magnitudes in terms of users have been tried to be explained in an explanatory language. For the same purpose, electrical parameters have been also examined and their meanings terms of both the user and system have been given. Based on the results obtained, evaluation of the light sources selected from different technologies have been provided sophisticatedly and their suitability in terms of users and systems have been discussed. In the last part, the loading efficacy value has been examined and reference has been made to the appropriateness of the use of this value in expressing the efficiency of the light sources.

Smoke suppression of [Glu]H2PW12O40 in thermoplastic polyurethane elastomer

As is known there is a large amount of smoke released from the combustion process of thermoplastic polyurethane elastomer (TPU). To reduce the fire risk of TPU is one of the research contents in the fire safety fields. In this paper, [Glu]H2PW12O40 was used as smoke suppressant in TPU, and the smoke suppression effect of [Glu]H2PW12O40 was intensively investigated using nuclear magnetic resonance, scanning electron microscope, cone calorimeter test (CCT), smoke density test (SDT), and thermogravimetric analysis/infrared spectrometry, respectively. In the CCT test, the peak value of smoke production rate (SPR) of TPU-3 with 0.5 mass% of [Glu]H2PW12O40 was 0.036 m2 s−1, reduced by 75% compared with the peak SPR value of TPU-0 without [Glu]H2PW12O40 (0.145 m2 s−1). [Glu]H2PW12O40 could decrease the total smoke release (TSR) from 1560 to 694 m2 m−2. And [Glu]H2PW12O40 could decrease the smoke factor from 1838 to 538 W m−2. The SDT results showed that the luminous flux value of TPU-3 with 0.5 mass% of [Glu]H2PW12O40 decreased by 30% compared with pure TPU at the end of the test without flame. The photographs from the CCT test showed that [Glu]H2PW12O40 could promote char residue formation. TG test also revealed that [Glu]H2PW12O40 could improve the thermal stability at high temperature. At the end of thermal decomposition, the mass of TPU-3 with 0.5 mass% of [Glu]H2PW12O40 increased 6.3% compared with the mass of TPU-0 without [Glu]H2PW12O40. Based on the above result, it could be concluded that [Glu]H2PW12O40 can suppress smoke generation by promoting char generation. In addition, [Glu]H2PW12O40 has a good prospect in smoke suppression of TPU.

Luminance mapping of light sources using ray sampling and compression

ABSTRACTIn this paper, a ray sampling method for calculating the luminance maps of light sources and compressing the ray files is proposed. The approach can directly derive luminance maps ofa light source from the ray file. The Fibonacci lattice model and the Kriging techniques are used to reconstruct the rays and to interpolate the luminous flux values of the new rays from the original ray data, respectively. A planar LED is used for the verification experiments. Luminance maps are simulated via sampling a ray file of the LED, and compared with actually measured luminance maps. A good agreement is found by high NCC and low NRMSE values as wellas the visual comparisons,and indicates the effectiveness of the proposed method. In addition, the ray emission experiments are performed,and the experimental results preliminarily validate the ability of the proposed sampling method in terms of compressing ray data.

Excellent luminous flux of WLEDs with flat dual-layer remote phosphor geometry

This paper focuses on the comparison of the luminous flux of two dual-remote phosphor structures named flat dual-remote phosphor (FDRP) and concave dual-remote phosphor (CDRP). These two configurations have different luminous flux values due to the disparity in scattering properties in white LEDs. However, the researched results showed that FDRP structure is more lucrative than the CDRP structure when it comes to the luminous flux effectiveness. To support the aforementioned idea, this article also presents the influence of the distance between two phosphor layers (d1) and the distance between the phosphor layer with the LED surface (d2) on the optical properties of the FDRP structure. Specifically, the scattering ability and absorption properties of the remote phosphor layer will vary sharply if d1 and d2 are adjusted into different values, which produces an immense impact on the chromatic homogeneity and illumination capability of WLEDs. Therefore, in order to stabilize the correlated color temperature (CCT) of WLEDs at 8500 K when there is a modification on d1 and d2, the concentration of YAG:Ce3+ phosphor also needs to be varied. Accordingly, the scattering process and absorption phenomenon in the remote phosphor layer will bottom out when d1 = d2 = 0, leading to the worst color quality and luminous flux. The effect of the spectra generated as these distances are adjusted is obvious evidence for this point. In other words, the larger the d1 and d2, the larger the scattering surface, and thus the blending of blue and yellow light rays will become more homogeneous, yielding the smallest white light deflection and the lowest luminous flux at the same time. The paper's results indicated that the luminous flux will reach a peak at 1020 lm if d1 = 0.08 mm or d2 = 0.63 mm and the chromatic deflection will hit the lowest point as d1 = 0.64 mm or d2 = 1.35 mm. In the end, manufacturers can make their choice for the production of higher-standard WLEDs based on the general knowledge and helpful information that the article has provided and analyzed.

Design of a Chip on Board (COB) LED Based Industrial Luminaire with Thermal Simulations

As the equipment is improving, the luminous efficacy of Chip on Board (COB) LEDs are increasing. In this study, the utilization of COB LEDs in an industrial high-bay luminaire, which can be considered as a relatively high power application, has been investigated starting from the initial design process. For an industrial hall, single-chip LED based reference luminaires, which can provide the required lighting quality criteria have been identified. COB LED selection and photometric measurements are done, and the number of COB LEDs to be used has been calculated by targeting the luminous flux value of reference luminaires. The COB LED based luminaire prototype with a plate finned heat sink was modelled by using a CAD software and the computer aided thermal simulations were performed. Then the prototype was manufactured and experimentally analysed. The highest difference between the experimental analysis and the thermal simulation was found to be less than 7 %, which demonstrates the consistency of design and analyses. This study is an example of the steps to be followed in the manufacturing stage of a COB LED based luminaire. Additionally, it is aimed to provide a perspective to the use of COB LEDs in high power applications.

Unprecedented Selenium and Lanthanide Simultaneously Bridging Selenotungstate Aggregates Stabilized by Four Tetra-vacant Dawson-like {Se2 W14 } Units.

In the presence of the larger [H2 N(CH3 )2 ]+ and K+ counter cations as structure-stabilizing agents, a class of unprecedented selenium and lanthanide (Ln) simultaneously bridging tetra-vacant Dawson-like selenotungstate aggregates [H2 N(CH3 )2 ]2 Na9 K2 H19 {[Ln4 W4 Se4 O22 (H2 O)5 ](Se2 W14 O52 )2 }2 ⋅60 H2 O [Ln=TbIII (1), DyIII (2), HoIII (3), ErIII (4), TmIII (5), YbIII (6)] have been obtained by the one-pot assembly reaction of Na2 WO4 ⋅2 H2 O, Ln(NO3 )3 ⋅6 H2 O, and Na2 SeO3 under moderately acidic aqueous conditions and the complexes were structurally characterized by elemental analyses, IR spectra, single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. It should be noted that the appropriate molar ratio of Se/W is extremely important in the formation of 1-6 and can effectively ameliorate the yield of 1-6. Moreover, dimethylamine hydrochloride is also indispensable and plays a considerably important role in improving the solubility of Ln ions and stabilizing the structures of 1-6. The main polyoxoanion skeletons of 1-6 are constructed from two sandwich-type tetra-vacant Dawson-like {[Ln4 W4 Se4 O22 (H2 O)5 ](Se2 W14 O52 )2 }16- half-units linked through two W-O-Ln bridges. The sandwich-type half-unit comprises two tetra-vacant Dawson-like [Se2 W14 O52 ]12- fragments encapsulating a unique dodecanuclear Se-Ln-W [Ln4 W4 Se4 O22 (H2 O)5 ]8+ oxo cluster. Their solid-state visible and NIR fluorescent properties and lifetime decay behaviors were measured and their solid-state luminescent spectra mainly demonstrate the characteristic emission bands of Ln3+ ions. Moreover, the dominant wavelengths, the color purity, and correlated color temperatures of 1-5 have been also calculated. In addition, the luminous flux values of 1-5 are 2031, 6992, 3071, 921, and 477 lumen, respectively.

Advantages of LED Lighting System in Comparison with Traditional Fluorescent Lamps for Simple Examination Rooms in Healthcare Facilities

This paper presents a detailed comparison between a new type of antibacterial LED panel and fluorescent lamps connected to electronic ballast in a simple examination room, which requires 300 lx in a healthcare facility. Within the study, power consumption (W), luminous flux (lm) and luminous efficacy of both light sources were measured. Luminous flux values were then compared to the amount of power they consumed. Electrical power consumption of these luminaires was also analyzed. To enable an objective comparison between these two types of luminaires ReluxDesktop_2017.1.10.0 simulation program was used. To verify the results obtained by the ReluxDesktop, photometric measurement results of the products were also obtained. The results obtained by the study have shown that the LED panel to be used in the healthcare facility may decrease the maintenance and lighting costs by saving energy while maintaining the illumination levels required by the healthcare facility lighting standards.

MODIFICATION AND REENGINEERING OF ELECTRONIC FISH AGGREGATING DEVICE AS A FISHING TOOLS BASED ON LED ILLUMINANCE

Fish Aggregating Devices (FADs) is generally made from foliage like a leaf of coconut, palm and nut, but with the development of marine and fishing technology, the FADs could be made electronic ally. Electronic FADs had been developed by using light and sound as an attractor, and was able to aggregate fish but the catch harvest was still relatively low compared with lift net lamp. In this paper we describe the recent development of electronic FADs. The new electronic FADs has 120 watts total power of LEDs as attractor, 12V 12Ah battery as the energy resources, and HDPE as the body of FADs. The lighting of the new is either blue – red light color (RE1) or red-white light color (RE2). The two kinds of lighting are tested and compared and its light distribution underwater case measured in term of the value of luminous flux. The results showed that new FADs work well in the water with light penetration of RE1 was better than RE2. Keywords: FADs, instrument, fishing, light

Synergistic fire safety effect between nano-CuO and ammonium polyphosphate in thermoplastic polyurethane elastomer

This article mainly studied the synergistic fire safety effect between nano-CuO and ammonium polyphosphate (APP) in thermoplastic polyurethane elastomer (TPU). The TPU composites were prepared by molten blending method. And the fire safety of all TPU composites was investigated by LOI test, cone calorimeter test (CCT), microscale combustion colorimeter (MCC) and smoke density test (SDT), respectively. The LOI test showed that nano-CuO could further improve the flame retardancy of TPU. The CCT results showed that there was a remarkably synergistic fire safety effect between APP and nano-CuO in TPU. Remarkably, the total heat release and total smoke release for the sample with 0.5 mass% content of nano-CuO decreased by at least 13.0 and 51.1% compared with the sample containing only APP, respectively. And the residual carbon mass of the samples containing nano-CuO was more than that of the sample with only APP at the end of the test. The MCC results showed that the HRR values of the samples containing nano-CuO were further lower than that of the sample containing APP. The SDT results showed that the luminous flux values of the samples containing nano-CuO were higher than that of the sample with only APP irrespective of with flame or without flame, which indicated that there was an apparently synergistic effect of smoke suppression between APP and nano-CuO in TPU. Through the analysis of the results of this experiment, it will make a great influence on the study of the nanomaterials in the aspect of fire safety of polymer.

MODIFICATION AND REENGINEERING OF ELECTRONIC FISH AGGREGATING DEVICE AS A FISHING TOOLS BASED ON LED ILLUMINANCE

<p><em>Fish Aggregating Devices (FADs) is generally made from foliage like a leaf of coconut, palm and nut, but with the development of marine and fishing technology, the FADs could be made electronic ally. Electronic FADs had been developed by using light and sound as an attractor, and was able to aggregate fish but the catch harvest was still relatively low compared with lift net lamp. In this paper we describe the recent development of electronic FADs. The new electronic FADs has 120 watts total power of LEDs as attractor, 12V 12Ah battery as the energy resources, and HDPE as the body of FADs. The lighting of the new is either blue –</em><em> </em><em>red light color (RE1) or red-white light color (RE2). The two kinds of lighting are tested and compared and its light distribution underwater case measured in term of the value of luminous flux. The results showed that new FADs work well in the water with light penetration of RE1 was better than RE2. </em></p><p><em> </em></p><strong><em>Keywords:</em> </strong><em>FADs, instrument, fishing, light</em>

OPTIMIZATION OF THE SOLAR LIGHT GUIDES CHOICE FOR THE UNIFORM ROOMS SURFACE ILLUMINATION IN THE BUILDINGS

The application of the hollow tubular light guides for the rooms’ natural illumination, where the use of other methods is difficult or impossible, is an innovative technology. The calculation of the required number of light guides is connected with various factors affecting on the luminous flux value in the light guide output and, consequently, on the illumination surface. The article presents the problem solution model of the choice of optimum amount of light guides, providing standardized illumination of the room, with considering sizes and constructive features of the installation, and the distance between the light guides.

Robot goniophotometry at PTB

The total luminous flux of a light source is the complete integration of its spectral radiance distribution weighted with the photopic observer and taken over all parts of its surface and over the full solid angle of emittance. The spatial distributions are measured with various types of goniophotometers and the PTB robot goniophotometer is a new type with many unique features. It is built as an arrangement of three robots with arms of more than 6 m in length and with 7 degrees of freedom each. The extreme flexibility of the robots allows computer controlled tracks with variable radii and speeds up to 3 m and 1 m s−1, respectively. One robot aligns the light source and the two other robots move photometers and array spectrometers in their hemispheres simultaneously measuring planar illuminance and the related relative spectral distribution. The robot goniophotometer is optimized for the realisation of the luminous flux unit, the lumen and it is completely characterized in this report. The relevant properties and correction factors are explained, as well as the implementation of techniques for synchronisation and stabilisation of spatially resolved or integrated photometric and colorimetric quantities. Finally, all contributions are combined in the model of evaluation for the (total) luminous flux value and the measurement uncertainty associated with that value is evaluated in the presented uncertainty budget. The goniophotometric determination of the values for colorimetric quantities is explained for the total luminous flux and the spatially distributed radiant power.