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Baby Disease LED Lighting

 

Baby Disease LED LightingAfter a shaft of optimistic forecasts about the imminent crowding out of incandescent LEDs, there was a lull. The first samples of LED lamps did not cause delight, but rather bewilderment. Are these pathetic, blinding eyes sources of light designed to replace the usual light bulbs with filament?

Let's try to answer this, and several other questions. The advent of blue LEDs in 1998 paved the way for solid-state white light sources. After that, the scope of LEDs began to expand rapidly: from the traditional illumination of dashboards to the replacement of fluorescent lamps in televisions and monitors with LCD panels.

But the impressive progress of semiconductor sources has not affected household lighting. According to one version, LED lamp too expensive, so they are not popular with buyers. We will try to figure out whether this reason alone inhibits the demand for the latest light sources.

Types of LED BulbsVariety of designs led bulbs It does not reflect the popularity of the source in domestic applications, but rather, attempts to overcome the difficulties that lighting engineering encountered in introducing solid-state light sources.

These difficulties are associated with the peculiarities of LEDs: they are “truly” point sources and emit light in a narrow solid (spatial) angle with a brightness comparable to the arc of a welding machine.

Before that, we were dealing with lamps that shine in a wide solid angle close to 360 degrees. In luminaires, due to various tricks, the luminous flux of the lamps is redistributed in the right direction, while 20-25% of the light is lost.

The blinding effect of the "point" filaments is suppressed by the use of diffusers, which, in turn, again "take" part of the light flux. This was the case before the advent of LEDs.

LEDs have a radiant area of ​​a semiconductor junction that is really point-like, with micron sizes. After collecting the radiation with internal optical elements, we get an unusual picture of a bright, blinding source with a narrow, similar to a chamomile petal, pattern of light emission. It has not yet been possible to expand it to obtain the usual distribution of light flux without serious losses.

LG LED lampAnother problem of LEDs, especially powerful ones, is the degradation of the emitting crystal with increasing temperature. Reading about the fantastic lifespan of LED lamps, one wonders at the craftiness of sellers. They indicate the values ​​that are obtained when testing LEDs in the laboratories of the manufacturer, at a fixed crystal temperature.

Under these conditions, the service life is really up to 100 thousand hours or more. In general, if it was possible to maintain the temperature of the semiconductor junction at subzero temperatures, then the LEDs worked “forever”.

In practice, in high-power diodes, the transition temperature can reach 100-120 degrees, while the dopants due to diffusion “leave” the transition zone and the light flux, which means that the efficiency drops sharply.

High-power LEDs with currents above 100 mA require special power devices that “rigidly” support the nominal value of the current through the diode. Deviation of the operating current in either direction dramatically reduces the efficiency of the LED, and excess is fraught with failure of the emitting crystal.

Now about the service life. For lamps with a group, series connection of diodes, the reliability decreases in proportion to the number of diodes. With several dozens of elements, it is not necessary to expect a service life of more than 5-10 thousand hours.

Powerful LEDs last longer, up to 50 thousand hours.But they require the use of a special power supply: a single or multi-channel driver (AC to DC converter with stabilization). A bulky heatsink is also needed to remove heat. Therefore, such lamps are much more expensive.

What do we have in practice? Unusual light, uneven lighting of the room with bright spots in one place and shadows in another - these are the most harmless consequences of replacing traditional lamps with LED ones. It immediately becomes apparent that the power of solid-state sources to get the usual lighting is not enough. Need more powerful LED lamps. But they will also look like foreign strangers, creating the same unevenness of lighting.

An example of interior lighting with LED lampsIs there a way out of this deadlock? Of course there is! For this, the end consumer should not be offered a separate lamp, but a lamp-lamp kit, in which the lighting parameters of new light sources are optimized for the usual lighting environment of the rooms. You can already offer several solutions today.

The first of these is the use of optical fibers. Once popular lighting systems, in recent years they have practically not been used due to the difficulty of focusing and introducing light into the systems. But LEDs are ideal for such distributed lighting systems. A narrow luminous flux introduced from the ends is scattered along the length of the fiber, providing soft, even illumination of the room. In this case, the glare of the LEDs is completely eliminated.

Modern materials used for strip (linear) systems of decorative LED lighting type duralight, may well become the basis for fixtures of an unusual shape with acceptable power.

An ordinary disk made of suitable polymer material, with modern LEDs placed on the rim (an analogue of the illumination of liquid crystal matrices), looks much more attractive than LED lamps in traditional chandeliers.

The situation with LED lamps and their application is now so complicated that of the leading lighting companies, only Philips risked to release several of its lamp models on sale. The rest of the "grandees" of lighting technology either wait, or without sources of noise, develop sources that can really find wide application in everyday life.

In the meantime, the market has been captured by many Chinese firms that sell many low-power lamps, shifting the problem of their adaptation to home lighting conditions to buyers. For those who already today want to move from words to deeds and in practice make sure of the reality of the above problems, it is possible to recommend the parameters of several lamp models available on the market.


Of the lamp models with a group connection of LEDs, corncob lamps with a circular light emission pattern are suitable. For example, the Maxsus A60 model with a power of 12 watts, a luminous flux of 1100 lumens and a price of about $ 20 per lamp. Of the more well-known manufacturers, a Philips product with a power of 10.5 W, 900 lumens at a price of $ 50 is suitable. For a 3-horn chandelier, the cost will range from 50 to 150 dollars.

But in this case, you need to be prepared for the fact that the illumination of your room will be insufficient. The fact is that we omitted another unpleasant feature of LED lighting - the physiological perception of light from such sources. Therefore, the required illumination is 25-30% higher than with incandescent lamps.

Significant success in the development and production of LEDs and LED modules with power up to 100 W will inevitably lead to the appearance of lighting systems that are convenient for use in everyday life. So far, unfortunately, there are no LED lamps suitable for home lighting.

22.04.2013


Other articles about LED lighting:

Parameters of LED light sources, characteristics of LED lamps

How to choose a LED lamp

LED strip application

The difference between LED lamps and compact fluorescent

See also at bgv.electricianexp.com:

  • Advantages of LED Lighting
  • Challenging LED Lamp Power Issues
  • Where are the LEDs used?
  • Parameters of LED light sources, characteristics of LED lamps
  • Requiem for incandescent lamps

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    Comments:

    # 1 wrote: Nikolay | [quote]

     
     

    I completely agree with everything that is said in the article. LED lamps are still in their infancy, and it is too early to talk about any feasibility of mass use. So far, they have inherent disadvantages that do not allow such lamps to compete normally with classic light sources (CFLs, halogens). However, LED lighting certainly has a future. It only takes time for their technical development for use for the needs of general lighting. Moreover, as stated in the article, the main players in the world lighting market (except Philips) have not yet entered into this topic. And China rarely produces normal quality products and judging by their attempts to make normal LED lamps on the whole topic is not very correct. In the meantime, LED lamps normally fit only into the niche of decorative lighting. In other cases, because of their shortcomings, they are not yet quite competitive.

     
    Comments:

    # 2 wrote: | [quote]

     
     

    Wonderful article! For me, everything related to LED lighting is very interesting! Write further on this topic!

     
    Comments:

    # 3 wrote: ak | [quote]

     
     

    Yes, they are still expensive for purchase. Menager’s spells about saving in the future do not work if you need to throw 2-3tr onto the chandelier right now.

     
    Comments:

    # 4 wrote: Valery | [quote]

     
     

    Not bad LED lines work in lamps like Armstrong for office lighting, but they need improvement. We add another 3 lines of warm-light LEDs to the standard 4 lines of cold white or daylight LEDs, naturally with the appropriate driver. There is enough space in the lamp and installation does not require high qualifications. It turns out a comfortable light, no worse than from fluorescent lamps. For the price it is still about 1200 rubles to the cost of the lamp (and for bulk purchases even less). But noticeable energy savings: one modified 600x600 mm LED lamp with a power of about 60 watts replaces a 1200x600 mm lamp of 4 fluorescent lamps with a total capacity of 144 watts, plus savings on the frequent replacement of burned out lamps and starters.

    For the home, this of course is not suitable in appearance, and the cost of electricity for household needs is lower, the savings are not so noticeable.

     
    Comments:

    # 5 wrote: | [quote]

     
     

    Can you imagine how much it was necessary to lobby the system in order to convert a big city (millionaire) to LED street lighting? For the experiment, they equipped part of one of the central streets - ul. Gorky, N.Novgorod.

    The result is miserable - the shadows roam on the roadway, poor lighting of vertical objects (pedestrians), a clear decrease in traffic safety due to LED lighting. But all these shortcomings are already closed.

    A project is being prepared to transfer all city lighting to the new LED lighting technology.

    A ray of light in the dark kingdom - there will be no more precise epithet!

    There are other technologies described on the site.

     
    Comments:

    # 6 wrote: | [quote]

     
     

    That's right, inaccuracy in the article about the size of the emitters. Not microns, but millimeters. And given the phosphor, sometimes tens of millimeters.

    And in addition to a sharp reduction in the life of the LEDs from overheating, it should be borne in mind that the phosphor used at high temperatures and very high radiation intensities of the LED quickly burns out, which makes the brightness of the light drop even faster.

    Most LED lamps blink quite disgustingly at the mains frequency.

    To date, the most optimal solution is compact fluorescent lamps. Today they are already quite cheap, economical and have a very decent spectrum of radiation.And horror stories about mercury are for the western man in the street. And it’s not in the mouth that drags her!

    The only indisputable advantage of LED lamps is their mechanical strength. They are not afraid of falls and bumps. And the rest is still far inferior to compact fluorescent lamps.

     
    Comments:

    # 7 wrote: | [quote]

     
     

    Yes, of course, statements about 100,000 hours of LED lighting are fun. With an average rate of 1,000 hours per year, in theory, they should be enough for 100 years of work. :) That's just the soldering of the mounted elements on the power supply, and the soldering on the matrix itself with LEDs is degrading. If you take any printed circuit board twenty years ago and look at the solder, you can see that 80% of the "tin droplets" are cracked and do not have reliable contact ... So even the operating time of more than 20,000 hours is doubtful. There, I recently bought five energy-saving Holz lamps for a new chandelier. Like Germany, and not the cheapest. Socket E14, and the base of the lamp is small, I liked it, I bought it. One lamp went out after three days. I dismantled this light bulb and saw that the electrodes from the filament were attached to the electronic ballast board on twists. Single-core wires of 5 millimeters in length are soldered to the board and thin wires are wound around them, leaving the lamp bulb. The twist is weak, the wiring is black (initially oxidized). One of the four twists sparked with emotion ... Soldered, lightened a light bulb. Hurrah! A week later, another lamp began to burn "in the floor." How can a fluorescent lamp burn with half the brightness? Probably in the electronic ballast another soldering fell off. There is no time to suffer garbage, threw it away, bought a new one. I'm afraid how energy-saving light bulbs for $ 5 are collected, and LEDs for $ 50 can be collected. And the question is, do I need light bulbs for $ 50, if I need to disassemble and solder every fifth lamp bought ... I can throw out an energy-saving lamp for $ 5 after 10 hours of operation, but after 10 hours of operation, I can throw out the LED for $ 50 I'm not ready. After all, there is not always time and desire to poke around with a soldering iron in the Chinese non-solders. And some transistor dies in the power supply of the LED lamp, so you still need to go to the store, buy it, and before that you need to look through the catalogs and find out which available transistor is an analog of this native Chinese .... Oh well, these LEDs are needed fixtures !!! The article describes all of their critical shortcomings. Plus, there’s still reliability, which doesn’t correspond to the declared characteristics ... No, not at them!

     
    Comments:

    # 8 wrote: | [quote]

     
     

    Quote: Victor
    Here are just the soldering of the mounted elements on the power supply, and the soldering on the matrix itself with LEDs is degrading. If you take any printed circuit board twenty years ago and look at the solder, you can see that 80% of the "tin droplets" are cracked and do not have reliable contact ...

    By the way, another disease of our time: "lead-free" solder. This is when it is enough to lightly tap the board edge on the table, and elements from it are strewed like apples from a tree ... There is no reliability of such rations. Apparently, such a time bomb was specially laid in modern electronics ...

     
    Comments:

    # 9 wrote: | [quote]

     
     

    I agree on many points, but now I collect a lamp with 30 cmd LEDs, for lighting the keyboard - we will see.

     
    Comments:

    # 10 wrote: | [quote]

     
     

    I personally engage in LED lighting for year 3, the first experiment I hung a 1-watt diode at the corner of the house, illuminates it in a radius of 5 meters - of course you can’t read the newspaper but you can clearly see where you are going to stumble on something and burns for days and nights. then I hung up a bunch of LEDs in the room to determine how much I need to light them for about 2 years, during this time more interesting options appeared, today in two rooms there is full LED lighting, in the 1st 12 3-walled LEDs in two standard converted lamps in the second 9 redone spotlights.about the blinking of the LEDs, complete nonsense - my version works from 150 to 260 without any reaction to the inclusion of vacuum cleaners, etc.

     
    Comments:

    # 11 wrote: | [quote]

     
     

    He began to engage in LED lighting at the dawn of its formation. I buy directly from the Chinese and do not regret it. The main thing is to find the right seller or manufacturer immediately. A LED is a different light source and you need to use it differently. Using LED lamps in chandeliers is simply stupid. But glue the LED strip around the perimeter of the room and immediately take away all the advantages of daily use. And use an ordinary chandelier for a festive feast. Excellent 1-3 wadded with lenses for table lamps. My yard is illuminated directly from the window by a trellis with a beam of 30 degrees every night and I don’t remember how old it is. In its "six" except the main headlights, only LEDs. Rear turns and brakes are odd (P214 body instead of the radiator and mount in place of the discarded slot) and need a stabilizer. Shine cooler than lamps. By the way, the incandescent lamp lights up in 0.3 seconds, and at a speed of 60 km / h it is more than 10 meters of the path. For safety, motorists are simply required to put LED lamps on the brakes. The remaining bulbs were replaced by LEDs of the 5050 form factor - from one to three. The unwanted lamp was smashed into a plus by a quenching resistor and a LED to it to the base. I fix the LEDs with hot glue or silicone. No one notices the difference. Now there are a lot of LED spotlights from 10w and more and costing from $ 15. On the cost account - 1-3w - from $ 3 to $ 5; 10w - $ 7 ... $ 15 for normal Chinese. When buying, pay attention to the availability of a technical passport or description directly on the package. Met packaging even without specifying the manufacturer (only voltage and power) - complete crap! The general conclusion is that each light source has its own place of application.

     
    Comments:

    # 12 wrote: | [quote]

     
     

    I am buying a MAXUS A65 12W 3000K 220V E27 AL - this lamp costs $ 15 and is almost comparable to 100 Watt LN (Soft yellow light, the eyes are not very blind). The only drawback is the angle of dispersion. But due to the lampshade, this is almost completely compensated.

     
    Comments:

    # 13 wrote: Const | [quote]

     
     

    Quote: Igor
    ... the phosphor used at high temperature and very high light emitting diode intensity quickly burns out

    The problem is not so much in the phosphor as in the wrong heat dissipation.

    Quote: Igor
    Most LED lamps blink quite disgustingly at the mains frequency.

    This is due to the lack of a normal filter in the power rectifier.

    Those. these are not fundamental problems. They are due to the “saving” of traders who organize production.

    Quote: Igor
    ... horror stories about mercury - for the western man in the street. And it’s not in the mouth that drags her!

    Ultimately, that's right - in the mouth. The entire biosphere is contaminated with waste. Including and mercury. And organic mercury compounds (which then form in the biosphere) are hundreds of times more toxic than the elemental form of mercury (after the spill of which you have to deal with expensive decontamination).

     
    Comments:

    # 14 wrote: Helena | [quote]

     
     

    Interesting stuff. Thanks to the author. Just a question: when was this article written (did not find a date)? How is this relevant for 2014?

     
    Comments:

    # 15 wrote: | [quote]

     
     

    no need to fault China. normally produces. iphone and many others are made in china. You have left the main thing ... this is the efficiency of the LED. it is best used where solar cells are used. and who needs comfort, it’s not for LEDs

     
    Comments:

    # 16 wrote: | [quote]

     
     

    Do not forget about energy saving. This is important in our time.

     
    Comments:

    # 17 wrote: Roman Dyrkman | [quote]

     
     

    I did not encounter any of the horror stories described in the article. Put 6 LED lights in the bathroom. 300 rubles, domestic production, if not mistaken. A base with 2 pins - I do not remember what it is called. Since then, I don’t know grief. Already 3 years and 1 month has passed.Previously, during this time I managed to change the entire set of bulbs about 6 times. And with LEDs there are no problems, they shine brightly, and taking into account the fact that none of them burned out, it generally works well (before that I didn’t climb to change the bulbs until half of them burn out, because I’m too lazy and I need to buy them, etc., respectively received the light not in full). The fact that power consumption is many times lower is considered a nice bonus. So if you take into account all the factors in my specific situation, it turns out LED is more profitable on all fronts.

    In the remaining places in the apartment has not yet changed. I wait until at least one LED light bulb is screwed in order to be 100% sure that the transition to LEDs is correct. However, if they survive 2 more years, I won’t wait any longer, and I will consider the issue of a full transition to LEDs to be completely removed.

     
    Comments:

    # 18 wrote: Mel | [quote]

     
     

    "Today" ... "in its infancy" ...
    When is it today? When is the article written? in the year 95? In 98? Each article has its own time. Please indicate the date.

     
    Comments:

    # 19 wrote: | [quote]

     
     

    Since the beginning of 2014, LED lamps have fallen significantly in price and the price decline continues. If in February 2014 the E27 A60 retrofit paid 570 rubles for a 15w lamp, then in October 2014 it paid 320 rubles for similar lamps. In addition to lower prices, the quality of the lamps has noticeably improved. Of the more than 40 pieces installed in the apartment, only one that was installed in the kitchen in a closed lamp failed during the year of operation, and I changed this lamp under warranty. If in LED lamps of previous years of releases a pulsation of light was often observed, which was detected using a smart background camera, then the situation with pulsation is now practically solved by most well-known manufacturers. So, in principle, if you wish, you can choose LED lamps, for almost complete replacement of incandescent lamps and compact fluorescent lamps in residential premises.

     
    Comments:

    # 20 wrote: Dmitriy | [quote]

     
     

    Do not believe your eyes - now everything is Chinese. I bought two LED floodlights written 30 watts and a light type of about 3,000 lm, one more or less the other kind of pale. In general, I measured the current - one eats 20 watts, the other 11 watts, and this, together with losses in the power supply. So, do not believe it - better look for reviews and check! And don’t pay for bullshit!

     
    Comments:

    # 21 wrote: | [quote]

     
     

    Dear article author or site owner! I urge you to change the title of your article, as when writing in the search for "LED light in the apartment", your article is in the first position with the title "children's illness LED lighting." As an Internet marketer, I can tell you that such a headline misleads people and immediately fixes the negative in the perception of LED products. Please think of others! Change the title to a calmer one. Thanks in advance!

     
    Comments:

    # 22 wrote: | [quote]

     
     

    In the yard 2016 year. I replaced all incandescent and compact fluorescent lamps in my apartment and in my parents with LED ones. I decided to change absolutely everything and everywhere, except those built into electrical appliances. Even in small lamps where there were halogens with G9 replaced by LED. The main socles are E27 and E14. Power LED lamps chose 3, 4, 6, 10, 11 and 13 watts. Only about 40 pieces of lamps. 19 lamps were E27 of 13 watts. In 2 chandeliers, where E14 socles had to buy E14 inserts on E27 in order to put lamps at 13 watts, since on E14 lamps were on sale no more than 6 watts and their light was not enough. The color rendition of lamps was chosen> 82 for chandeliers and> 90 for lamps.

    Lamps shine in almost the same shade as incandescent light - very nice. Saving for a month on electricity in only one apartment, where there were previously incandescent lamps, amounted to about 1000 rubles.

     
    Comments:

    # 23 wrote: Novel | [quote]

     
     

    Outside is the end of 2016. Made a room lighting of 14 sq.m. four 550 meter LED strips 5050, bought on aliexpress, with reflection from the stretch ceiling.I rarely turn on all the tapes - it shines so brightly that you can go blind. All the pleasure cost about 600 rubles + 1500 for separate power supplies for each tape. So "childhood illnesses" are all from curvature, as it seems to me.

     
    Comments:

    # 24 wrote: Andrew | [quote]

     
     

    The end of 2018, I throw out the last fluorescent lamp. At home, all the lights are ice. In ikey light bulbs from 89 rubles. The article is already museum.