> Quick answer: High-quality solar lamps stand out due to rigorous component selection, specifically LED binning for color rendering (CRI, R9), robust electrical systems, and adherence to performance standards [9][10][13][14]. Poor-quality models often exhibit light output decay, poor color consistency, and system failures.
High-quality solar lamps are not defined by a single feature but by a constellation of engineering practices that ensure consistent, high-performance lighting. These lamps prioritize spectral quality, robust design, and adherence to performance standards—practices often omitted in low-cost models.
LED Binning and Quality Control
The most significant differentiator is LED binning, which involves sorting LEDs based on color temperature, luminous flux, and spectral output [9][21]. High-quality solar lamps maintain consistent light quality over time due to careful selection of LEDs with high CRI (Color Rendering Index) and R9 values. R9 measures the rendering of saturated reds, and LEDs with an R9 below 50 are considered mediocre despite their efficiency [9][21].
| Quality Level | R9 Value Range |
|–––––|–––––-|
| Mediocre | <50 |
| Good | 50–89 |
| Excellent | >90 |
Poor-quality LEDs often have high efficacy but poor color rendering, leading to rapid light output decay and spectral deficiencies [13][9]. In contrast, good-quality LEDs (R9 50-89) and excellent-quality LEDs (R9 >90) ensure superior spectral balance and minimal damage to sensitive materials like artworks or textiles [9][25].
Electrical and Mechanical System Design
Beyond LED selection, the durability of solar lamps depends on robust electrical and mechanical systems. Low-cost models frequently fail due to defective batteries, poor battery protection, and connector failures [10][13]. High-quality solar lamps incorporate advanced charge controllers and battery protection circuits that prevent deep discharge and extend battery life [10][14].
Thermal Management
LEDs are sensitive to heat, and poor thermal design can lead to performance degradation and early failure. LED flip chip designs exhibit better thermal dissipation during frequent on/off switching, reducing wire failures and improving longevity [8][12]. Heat sinks are crucial for high-power LED systems, as their design affects overall system efficiency [22].
System-Level Integration and Testing
High-quality solar lamps are designed with real-world use in mind. Lab tests alone are insufficient; field testing reveals design flaws due to user behavior such as carrying the lamp or exposing it to harsh environments [7][13]. High-quality lamps incorporate rugged materials, sealed enclosures, and durable connectors to prevent degradation from gases like sulfur [12].
Standards and Certification
Lighting Global standards set minimum performance targets for off-grid lighting products, including four hours of light output and reduced environmental impact [14]. Energy Star criteria include constant light output over time, no flicker, instant-on capability, and low off-state power draw—reflecting a holistic approach to quality [21].
Key Takeaways
- High-quality solar lamps prioritize LED binning for spectral integrity and color fidelity.
- Robust electrical systems and battery protection are crucial for durability.
- Effective thermal management extends the lifespan of LEDs.
- Field testing is essential to ensure real-world performance.
- Adherence to standards like Lighting Global and Energy Star certifies high quality.
References
- [7] Impacts_of_PicoPV_and_Consumer_Research_-_energypedia__2ed9d7cd — authority
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# Impacts of PicoPV and Consumer Research Source: Blog/Web URL: https://energypedia.info/wiki/Impacts_of_PicoPV_and_Consumer_Research Author: Date: 2018-08-01 Impacts of PicoPV and Consumer Research Overview As experience with other renewable technologies show, lack of social acceptance and incongruity with cultural values and norms are common barriers during the implementation phase. Therefore, it is important to investigate in users needs and behavior patterns. Additionally, experience shows that laboratory test have to be complemented with field tests in order to test the solar lanterns under real-life conditions. Due to the fact that many bad quality products exists, it is also important to test selected products in a field test. GIZ Energising Development has conducted various tests in different countries, such as Bangladesh, Bolivia, Ethiopia, Mozambique, Nicaragua, Peru, Senegal and Uganda. Approaches of these tests differ, results and outlook are presented within this articles. Performance of Solar Lamps More than 100 firms are offering PicoPV products in developing countries today, but most products are of very low quality, with serious implications for consumer trust in the new technology. Early lab tests have focused the awareness of governments and donors on the importance of quality control and customer information – however, field tests in sufficient countries with sufficient sample sizes are needed for a better understanding of PicoPV performance under real-lif
- [8] US9494297B1_-_Solar-powered_LED_module_and_lighting_fixtures__76c7bd5c — patent
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lamps – Y02B20/72—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps in street lighting Definitions – Solid-state lighting fixtures such as those using light emitting diodes (LEDs) are not yet widely used for general illumination. Nonetheless, solid-state lighting technology is rapidly evolving, and more powerful LEDs are being released every 6-12 months. Though very energy efficient, LEDs are just now being developed with sufficient efficacy (i.e., light output for unit of energy input, or lumens per Watt) to enable lighting systems based on one or a small number of LEDs. As a result to produce sufficient illumination in most applications, prior art solid-state lighting systems utilized many LEDs, such as clusters of LEDs arranged on printed circuit boards in arrays and mounted to large, heavy, and expensive heat sinks. However, if an LED malfunctioned it was not efficiently replaceable. – LEDs light emitting diodes – LEDs could not be unscrewed simply and replaced as with other forms of lighting, such as incandescent, fluorescent, high-pressure sodium, metal halide, high-intensity discharge, and others. – LEDs could not be unscrewed simply and replaced as with other forms of lighting, such as incandescent, fluorescent, high-pressure sodium, metal halide, high-intensity discharge, and others. – the entire prior art LED array required replacement, and likely a complete heat sink redesign, because the system was most often constructed as a single
- [9] LED_Lighting_in_Museums_and_Art_Galleries_Technical_-_Canadaca__7f9b6307 — authority
source passage
quality of light. We can expect rapid development in the next few years, but currently, the bulk of LEDs on the market suffer the same compromise as fluorescent lamps and compact fluorescent lamps (CFLs): marketing favours high efficacy and low price. Quality of light comes a distant third. In Figure 4, in the top left corner, is a yellow box representing quartz halogen lamps: CRI near 100 and an efficacy around 20 lm/W. The black dots plot LEDs with an R9 below 50, the cut-off for good-quality light. These LEDs have high efficacy, starting around 80 lm/W and extending beyond 130 lm/W (data beyond 130 lm/W is not shown), but the CRI is mediocre, in the range of 80 to 85. The large data points without a red cross are good-quality LEDs, R9 between 50 and 89. Most have an efficacy in the range of 50 to 80, and thus require 2 1/2 to 4 times less electricity than a quartz halogen lamp to produce the same light. The large data points with a red cross inserted are excellent-quality LEDs, R9 above 90; most have an efficacy between 40 and 80, so they use two to four times less electricity. Note that most have a colour temperature in the range of 2901 to 3100 K (yellow squares). Each year, more high-quality and high-efficacy LEDs reach the market, and we can expect it to become easier for museums to find what they need. It is important to note that there are more excellent LEDs than indicated in Figure 4. Some companies known to supply high-quality LEDs have not entered their data in t
- [10] Impacts_of_PicoPV_and_Consumer_Research_-_energypedia__2ed9d7cd — authority
source passage
Outstanding Products). Particular technical improvements concluded from the Ugandan field tests are: manufacturers need to improve products’ solar fraction, equip lamps only with advanced charge controllers, and work on the robustness of the products, and of the connection parts in particular. Problems were: frequent deep-discharge of batteries, low battery life-spans and overall unsatisfactory lighting service were the frequently observed. Apart from that, the components that most often caused lamps to fail were cables, plugs, input jacks and switches. These parts are obviously under extreme stress when lamps are in everyday use by extended families with several children, and when modules are put down for charging on the ground in the courtyard (while lamps are kept inside to protect them against thieves). [1] In Ethiopia, broken switches and deeply discharged batteries were a frequent problem. Robustness has to be improved as well, because users often carry their systems around due to fear of theft. General Experiences Field Tests The GIZ PicoPV country survey results underpin that an ‘one-size-fits-all’ lamp model does not exist. The lamp models were rated differently by users across different continents, and they were liked and disliked for different reasons. However, there are some aspects that turned out to be important for consumers in all the test countries. Aspect's Customers Above all, light quality, including the size of the light cone and light intensity, mattered
- [12] LED_professional_Symposium_Expert_Talks_on_Light__Full_Spectrum_Horticulture_Lighting_Enriching_Crop_Quality_and_Output__13McvCTaUis — youtube
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a solution as they do not have wires at all the LED flip chip type exhibits better thermal dissipation during frequent on and off switching when compared to an epi up design as such wire failure is reduced thanks to frequently minimized material expansion and contraction LED performance degradation can be caused by chemical exposure for example LEDs can be damaged by sulfur in a horticultural environment sulfur is one of six essential nutrients and is commonly contained in chemical fertilizer sulfur is also used as an acidifier to lower the pH level of the soil and sometimes burned or vaporized for pest control and disinfection if an LED is not designed properly sulfur can react with the silver lead frame inside the LED and reduce its performance the chemical reaction creates a dark material and causes discoloration as shown here to prevent chemical reactions LEDs with protection schemes are more desirable an IP rating at the fixture level is not enough because ingress protect against solids and liquids not against gases so the LED itself needs to be sturdy covering the silver lead frame with a reflector structure or coating everything with a protection layer are some of the solutions we are using right now when we compare horticultural LEDs and normal LEDs in sulfur ization tests following the IEC standard the horticultural LED shows much better performance maintenance LEDs used for horticultural applications should be different from a normal LED in terms of reliability the
- [13] Solar_Laterns_Test_-_energypedia__6e1cce5f — authority
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phone charging, massive market growth can be expected in the near future. – In light of the mixed test results, informing potential consumers about lantern quality will be of great importance for a healthy market development. In the initial Test Level 1, ISE examined all twelve systems for quality of workmanship. Five lamps did not pass test level one. In general the tests show that a majority of the available lights are not suitable for “Off-Grid Lighting” ion developing countries due to their very poor quality, which would lead to very short lifetimes and bad lighting service for poor rural customers.[2] The main quality issues determined were: – Poor mechanical design and workmanship – Missing over-current protection of the LED – Poor electrical design – Insufficient light output – Bad quality of LEDs: rapid degradation of light output – Solar panels and batteries did not show their nominal values or were sized too small – Defective protection of battery – Defective ballast for LEDs or CFLs[2] Testing Criteria The following table shows the testing criteria and maint test evaluation of types of lanterns. [1] Taking the different evaluations into consideratin, the winner of the technical test was the sun x-set mobile. E ven if the two lanterns do not show the best workmanship, the system functions with the largest and most powerful module by far and with an outstandingly good and versatile charging station. The extremely high purchase price and consequently huge operating co
- [14] Revising_Standards_in_line_with_Technology_Developments__a88d12f4 — authority
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# Revising Standards in line with Technology Developments, Consumer Expectations – Lighting Global Source: Blog/Web URL: https://www.lightingglobal.org/revising-standards-in-line-with-technology-developments-consumer-expectations/ Author: Jen Date: 2013-08-12 Revising Standards in line with Technology Developments, Consumer Expectations The on-going consultation on the revision of the quality standards and performance targets for off-grid lighting products has been extended to 23 August. The consultation seeks to re-assess, update and strengthen the quality standards and performance targets of off-grid lights in order to keep up with, and anticipate market trends, and to incorporate new research findings, for example, on end-user preferences. The Lighting Global program, which is now responsible for maintaining harmonized quality standards for off-grid lighting products for rural consumers in Africa and Asia, has proposed a number changes intended to give better value yet to consumers and reduce the environmental footprint of the lights, most of which are solar-powered, and uphold them as truly “clean”. Some of the proposals include brighter, longer light output, durable battery quality, and adoption of the EU Directive on use of hazardous substances (mercury and cadmium) in batteries. The current standards for example require solar-charged lanterns to provide at least four hours of lighting per day. Consumers surveyed in both Africa and Asia however indicated need for longer
- [21] LED_lamp_-_WikipediaLight-emitting_diode_-_WikipediaLED_circuit_-_Wiki__b8e2933f — wikipedia
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not break like a glass bulb. To qualify for Energy Star certification, LED lighting products must pass a variety of tests to prove that the products will display the following characteristics: – Brightness is equal to or greater than existing lighting technologies (incandescent or fluorescent) and light is well distributed over the area lit by the fixture. – Light output remains constant over time, only decreasing towards the end of the rated lifetime (at least 35,000 hours or 12 annums based on use of 8 hours per day). – Excellent color quality. The shade of white light appears clear and consistent over time. – Efficiency is as good as or better than fluorescent lighting. – Light comes on instantly when turned on. – No flicker when dimmed. – No off-state power draw. The fixture does not use power when it is turned off, with the exception of external controls, whose power should not exceed 0.5 watts in the off state. – Power factor of at least 0.7 for all lamps of 5W or greater. LED emitters are inherently suitable for dimming, because they can operate over a wide range of currents without significant change of color. However, the circuits in LED lamps must be explicitly designed to be dimmable and compatible with particular types of dimmer switch.[103] Otherwise damage to the lamp and/or the dimmer may result. Color rendering is not identical to that of incandescent lamps, which emit close to perfect black-body radiation, as does the sun. A measurement unit called CRI is use
- [22] US9494297B1_-_Solar-powered_LED_module_and_lighting_fixtures__76c7bd5c — patent
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# Solar-powered LED module and lighting fixtures Source: Blog/Web URL: https://patents.google.com/patent/US9494297B1/en Author: Date: 2011-11-21 US9494297B1 – Solar-powered LED module and lighting fixtures – Google Patents Solar-powered LED module and lighting fixtures Download PDFInfo – Publication number – US9494297B1 US9494297B1 US13/301,575 US201113301575A US9494297B1 US 9494297 B1 US9494297 B1 US 9494297B1 US 201113301575 A US201113301575 A US 201113301575A US 9494297 B1 US9494297 B1 US 9494297B1 – Authority – US – United States – Prior art keywords – light – lens – heat sink – emitting diode – present disclosure – Prior art date – Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.) – Expired – Fee Related, expires Links – 230000003287 optical effect Effects 0.000 claims abstract description 96 – 230000003466 anti-cipated effect Effects 0.000 claims abstract description 4 – 238000009826 distribution Methods 0.000 claims description 16 – 238000004381 surface treatment Methods 0.000 claims description 8 – 230000005855 radiation Effects 0.000 claims description 5 – 230000013011 mating Effects 0.000 claims 2 – 230000006870 function Effects 0.000 description 16 – 238000005286 illumination Methods 0.000 description 16 – 238000000034 method Methods 0.000 description 13 – 239000000463 material Substances 0.000 description 11 – 230000008569 pr
- [25] LED_Lighting_in_Museums_and_Art_Galleries_Technical_-_Canadaca__7f9b6307 — authority
source passage
daylight. In fact, we find the opposite for the most important type of light damage: the discolouration of fugitive colours. When comparing all LED lamps that produce good or excellent light to lamps that have been widely used in the past without UV filters, such as traditional incandescent lamps and halogen lamps, we notice that the good-quality LED lamps are all safer, whether based on blue or violet LEDs. When comparing LED lamps to the benchmark of a halogen lamp with a perfect UV filter, we see that LED lamps of similar colour temperature and of good-quality light cause either similar rates of discolouration, if using a violet LED pump, or lower rates of discolouration, if using a blue LED pump. The lower rates of discolouration with blue LED lamps are due to the missing violet light (that is, their incomplete spectra). We do not consider this a reason to favour violet-deficient lamps any more than we would have recommended yellow filters for all incandescent lamps in the past. Is fading by LED lamps ever significantly worse than that associated with traditional lamps? Yes. Early work by Ishi and colleagues (2008) showed some dyes faded up to twice as fast with the worst LED lamp tested compared to a source similar to our benchmark 3000 K halogen with UV filter, but such early LED lamps produced light of very poor quality (very high CCT, poor CRI) and should never be used in a museum or art gallery. In summary, the only evidence of significantly increased fading concerne
# Impacts of PicoPV and Consumer Research Source: Blog/Web URL: https://energypedia.info/wiki/Impacts_of_PicoPV_and_Consumer_Research Author: Date: 2018-08-01 Impacts of PicoPV and Consumer Research Overview As experience with other renewable technologies show, lack of social acceptance and incongruity with cultural values and norms are common barriers during the implementation phase. Therefore, it is important to investigate in users needs and behavior patterns. Additionally, experience shows that laboratory test have to be complemented with field tests in order to test the solar lanterns under real-life conditions. Due to the fact that many bad quality products exists, it is also important to test selected products in a field test. GIZ Energising Development has conducted various tests in different countries, such as Bangladesh, Bolivia, Ethiopia, Mozambique, Nicaragua, Peru, Senegal and Uganda. Approaches of these tests differ, results and outlook are presented within this articles. Performance of Solar Lamps More than 100 firms are offering PicoPV products in developing countries today, but most products are of very low quality, with serious implications for consumer trust in the new technology. Early lab tests have focused the awareness of governments and donors on the importance of quality control and customer information – however, field tests in sufficient countries with sufficient sample sizes are needed for a better understanding of PicoPV performance under real-lif
lamps – Y02B20/72—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps in street lighting Definitions – Solid-state lighting fixtures such as those using light emitting diodes (LEDs) are not yet widely used for general illumination. Nonetheless, solid-state lighting technology is rapidly evolving, and more powerful LEDs are being released every 6-12 months. Though very energy efficient, LEDs are just now being developed with sufficient efficacy (i.e., light output for unit of energy input, or lumens per Watt) to enable lighting systems based on one or a small number of LEDs. As a result to produce sufficient illumination in most applications, prior art solid-state lighting systems utilized many LEDs, such as clusters of LEDs arranged on printed circuit boards in arrays and mounted to large, heavy, and expensive heat sinks. However, if an LED malfunctioned it was not efficiently replaceable. – LEDs light emitting diodes – LEDs could not be unscrewed simply and replaced as with other forms of lighting, such as incandescent, fluorescent, high-pressure sodium, metal halide, high-intensity discharge, and others. – LEDs could not be unscrewed simply and replaced as with other forms of lighting, such as incandescent, fluorescent, high-pressure sodium, metal halide, high-intensity discharge, and others. – the entire prior art LED array required replacement, and likely a complete heat sink redesign, because the system was most often constructed as a single
quality of light. We can expect rapid development in the next few years, but currently, the bulk of LEDs on the market suffer the same compromise as fluorescent lamps and compact fluorescent lamps (CFLs): marketing favours high efficacy and low price. Quality of light comes a distant third. In Figure 4, in the top left corner, is a yellow box representing quartz halogen lamps: CRI near 100 and an efficacy around 20 lm/W. The black dots plot LEDs with an R9 below 50, the cut-off for good-quality light. These LEDs have high efficacy, starting around 80 lm/W and extending beyond 130 lm/W (data beyond 130 lm/W is not shown), but the CRI is mediocre, in the range of 80 to 85. The large data points without a red cross are good-quality LEDs, R9 between 50 and 89. Most have an efficacy in the range of 50 to 80, and thus require 2 1/2 to 4 times less electricity than a quartz halogen lamp to produce the same light. The large data points with a red cross inserted are excellent-quality LEDs, R9 above 90; most have an efficacy between 40 and 80, so they use two to four times less electricity. Note that most have a colour temperature in the range of 2901 to 3100 K (yellow squares). Each year, more high-quality and high-efficacy LEDs reach the market, and we can expect it to become easier for museums to find what they need. It is important to note that there are more excellent LEDs than indicated in Figure 4. Some companies known to supply high-quality LEDs have not entered their data in t
Outstanding Products). Particular technical improvements concluded from the Ugandan field tests are: manufacturers need to improve products’ solar fraction, equip lamps only with advanced charge controllers, and work on the robustness of the products, and of the connection parts in particular. Problems were: frequent deep-discharge of batteries, low battery life-spans and overall unsatisfactory lighting service were the frequently observed. Apart from that, the components that most often caused lamps to fail were cables, plugs, input jacks and switches. These parts are obviously under extreme stress when lamps are in everyday use by extended families with several children, and when modules are put down for charging on the ground in the courtyard (while lamps are kept inside to protect them against thieves). [1] In Ethiopia, broken switches and deeply discharged batteries were a frequent problem. Robustness has to be improved as well, because users often carry their systems around due to fear of theft. General Experiences Field Tests The GIZ PicoPV country survey results underpin that an ‘one-size-fits-all’ lamp model does not exist. The lamp models were rated differently by users across different continents, and they were liked and disliked for different reasons. However, there are some aspects that turned out to be important for consumers in all the test countries. Aspect's Customers Above all, light quality, including the size of the light cone and light intensity, mattered
a solution as they do not have wires at all the LED flip chip type exhibits better thermal dissipation during frequent on and off switching when compared to an epi up design as such wire failure is reduced thanks to frequently minimized material expansion and contraction LED performance degradation can be caused by chemical exposure for example LEDs can be damaged by sulfur in a horticultural environment sulfur is one of six essential nutrients and is commonly contained in chemical fertilizer sulfur is also used as an acidifier to lower the pH level of the soil and sometimes burned or vaporized for pest control and disinfection if an LED is not designed properly sulfur can react with the silver lead frame inside the LED and reduce its performance the chemical reaction creates a dark material and causes discoloration as shown here to prevent chemical reactions LEDs with protection schemes are more desirable an IP rating at the fixture level is not enough because ingress protect against solids and liquids not against gases so the LED itself needs to be sturdy covering the silver lead frame with a reflector structure or coating everything with a protection layer are some of the solutions we are using right now when we compare horticultural LEDs and normal LEDs in sulfur ization tests following the IEC standard the horticultural LED shows much better performance maintenance LEDs used for horticultural applications should be different from a normal LED in terms of reliability the
phone charging, massive market growth can be expected in the near future. – In light of the mixed test results, informing potential consumers about lantern quality will be of great importance for a healthy market development. In the initial Test Level 1, ISE examined all twelve systems for quality of workmanship. Five lamps did not pass test level one. In general the tests show that a majority of the available lights are not suitable for “Off-Grid Lighting” ion developing countries due to their very poor quality, which would lead to very short lifetimes and bad lighting service for poor rural customers.[2] The main quality issues determined were: – Poor mechanical design and workmanship – Missing over-current protection of the LED – Poor electrical design – Insufficient light output – Bad quality of LEDs: rapid degradation of light output – Solar panels and batteries did not show their nominal values or were sized too small – Defective protection of battery – Defective ballast for LEDs or CFLs[2] Testing Criteria The following table shows the testing criteria and maint test evaluation of types of lanterns. [1] Taking the different evaluations into consideratin, the winner of the technical test was the sun x-set mobile. E ven if the two lanterns do not show the best workmanship, the system functions with the largest and most powerful module by far and with an outstandingly good and versatile charging station. The extremely high purchase price and consequently huge operating co
# Revising Standards in line with Technology Developments, Consumer Expectations – Lighting Global Source: Blog/Web URL: https://www.lightingglobal.org/revising-standards-in-line-with-technology-developments-consumer-expectations/ Author: Jen Date: 2013-08-12 Revising Standards in line with Technology Developments, Consumer Expectations The on-going consultation on the revision of the quality standards and performance targets for off-grid lighting products has been extended to 23 August. The consultation seeks to re-assess, update and strengthen the quality standards and performance targets of off-grid lights in order to keep up with, and anticipate market trends, and to incorporate new research findings, for example, on end-user preferences. The Lighting Global program, which is now responsible for maintaining harmonized quality standards for off-grid lighting products for rural consumers in Africa and Asia, has proposed a number changes intended to give better value yet to consumers and reduce the environmental footprint of the lights, most of which are solar-powered, and uphold them as truly “clean”. Some of the proposals include brighter, longer light output, durable battery quality, and adoption of the EU Directive on use of hazardous substances (mercury and cadmium) in batteries. The current standards for example require solar-charged lanterns to provide at least four hours of lighting per day. Consumers surveyed in both Africa and Asia however indicated need for longer
not break like a glass bulb. To qualify for Energy Star certification, LED lighting products must pass a variety of tests to prove that the products will display the following characteristics: – Brightness is equal to or greater than existing lighting technologies (incandescent or fluorescent) and light is well distributed over the area lit by the fixture. – Light output remains constant over time, only decreasing towards the end of the rated lifetime (at least 35,000 hours or 12 annums based on use of 8 hours per day). – Excellent color quality. The shade of white light appears clear and consistent over time. – Efficiency is as good as or better than fluorescent lighting. – Light comes on instantly when turned on. – No flicker when dimmed. – No off-state power draw. The fixture does not use power when it is turned off, with the exception of external controls, whose power should not exceed 0.5 watts in the off state. – Power factor of at least 0.7 for all lamps of 5W or greater. LED emitters are inherently suitable for dimming, because they can operate over a wide range of currents without significant change of color. However, the circuits in LED lamps must be explicitly designed to be dimmable and compatible with particular types of dimmer switch.[103] Otherwise damage to the lamp and/or the dimmer may result. Color rendering is not identical to that of incandescent lamps, which emit close to perfect black-body radiation, as does the sun. A measurement unit called CRI is use
# Solar-powered LED module and lighting fixtures Source: Blog/Web URL: https://patents.google.com/patent/US9494297B1/en Author: Date: 2011-11-21 US9494297B1 – Solar-powered LED module and lighting fixtures – Google Patents Solar-powered LED module and lighting fixtures Download PDFInfo – Publication number – US9494297B1 US9494297B1 US13/301,575 US201113301575A US9494297B1 US 9494297 B1 US9494297 B1 US 9494297B1 US 201113301575 A US201113301575 A US 201113301575A US 9494297 B1 US9494297 B1 US 9494297B1 – Authority – US – United States – Prior art keywords – light – lens – heat sink – emitting diode – present disclosure – Prior art date – Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.) – Expired – Fee Related, expires Links – 230000003287 optical effect Effects 0.000 claims abstract description 96 – 230000003466 anti-cipated effect Effects 0.000 claims abstract description 4 – 238000009826 distribution Methods 0.000 claims description 16 – 238000004381 surface treatment Methods 0.000 claims description 8 – 230000005855 radiation Effects 0.000 claims description 5 – 230000013011 mating Effects 0.000 claims 2 – 230000006870 function Effects 0.000 description 16 – 238000005286 illumination Methods 0.000 description 16 – 238000000034 method Methods 0.000 description 13 – 239000000463 material Substances 0.000 description 11 – 230000008569 pr
daylight. In fact, we find the opposite for the most important type of light damage: the discolouration of fugitive colours. When comparing all LED lamps that produce good or excellent light to lamps that have been widely used in the past without UV filters, such as traditional incandescent lamps and halogen lamps, we notice that the good-quality LED lamps are all safer, whether based on blue or violet LEDs. When comparing LED lamps to the benchmark of a halogen lamp with a perfect UV filter, we see that LED lamps of similar colour temperature and of good-quality light cause either similar rates of discolouration, if using a violet LED pump, or lower rates of discolouration, if using a blue LED pump. The lower rates of discolouration with blue LED lamps are due to the missing violet light (that is, their incomplete spectra). We do not consider this a reason to favour violet-deficient lamps any more than we would have recommended yellow filters for all incandescent lamps in the past. Is fading by LED lamps ever significantly worse than that associated with traditional lamps? Yes. Early work by Ishi and colleagues (2008) showed some dyes faded up to twice as fast with the worst LED lamp tested compared to a source similar to our benchmark 3000 K halogen with UV filter, but such early LED lamps produced light of very poor quality (very high CCT, poor CRI) and should never be used in a museum or art gallery. In summary, the only evidence of significantly increased fading concerne