LED Trend: Right or Wrong ?

[Viru]

Hi Viru,

Still you did't get the point. Let me explain once again.

You do only consider LED lights as it is coming from a small point source, that is why you feel difficulty in understanding. But what about the LED lights which spreads very well?
Viru, It need not to be a point source. Even if those LED light spreads better than our traditional incandescent bulbs still it is considered to be harmful, why????because it produces high levels of radiation in the blueband of the light spectrum.
Consider a 1watt 100lumens of LED light emitting from a small source of surface area and a 1watt 100lumens of LED light emitting from a 10cm sq surface area.
Here according to you the 2nd led with 10cm sq surface area of source is not going to cause any harm since it is not from a point source and its intensity is less comparing to the other, isn't it? What I'm saying is in the case of LED, irrespective of its 'light source surface area' it is going to harm our eyes since it produces high levels of radiation. NOt just the LEDs, any light source with high intensity of light is harmful for our eyes. Eg:- SPOTLIGHTS using filament bulbs or fluorescent bulbs or HID. Looking in to the Spotlights are also going to harm our eyes.

I will give you some examples for getting better idea.
Consider our electronic devices with LED displays. For example Laptop/desktop screens, Mobile screen etc.
Do you think the light coming from these displays are just like the lights coming from a normal 5 or 8mm LED panel???? definitely not isn't it.? Because light coming from the LED display spreads much better than those 5 or 8mm LEDs. Then why LED screens are said to be harmful? Why LED screens are said to be more harmful for eyes than those LCD screens with the 'same amount of brightness'? because of the same reason, LED produces high levels of radiation in the blueband of the light spectrum.
So here the matter is not about amount for light that comes from the led or the surface area(Yes, they do matters, But here in the case of LED this is not the actual problem, its the radiation). or else the LCD displays with same amount of brightness should also harm our eyes just like the LED displays do. But LEDs displays are said to be more harmful.

I request you to read those lines written in bold if you are still confused.

Cheers.

You seem to have misinterpreted the concept of the light spectrum and it's various components. The 'blue band' simply refers to the group of frequencies perceived by the eye to be between cyan and violet, it is just one component of white light. This is not even a particularly harmful range as the energy is still not excessively high. The harmful type of radiation is Ultraviolet (Not visible to the naked eye). This radiation is emitted by all light sources, the only issue being that only some types are adequately shielded with a UV blocking glass.

Also, the LED displays used for consumer electronics do not use bare LEDs. These simply use LED backlights instead of CCFL ones, and the layer of liquid crystals over them is retained. The phosphor coating of the LEDs in this application cuts out UV frequencies, so that does not pose a threat. It is possible that viewing LED displays can be strenuous due to the more sharp contrast and vivid colour, but this has nothing to do with radiation.

 

[Kichu]

Nice explanation
1)you are again referring to 'Light guides' They spread the Light evenly on the lens surface and you can't see individual LEDs. LEDs are actually hidden deep inside the housings. Result- Glare free and even LED light

2) Do not agree to your High spectrum/UV say. Do you feel problems working with LED display Mobile or laptop the same way you blame LEDs? If so they should have gone banned a long time ago. Problem is usually inferior lenses/Poor execution of housing and not the LED source itself.

Hi bhvm, I like your LED works. Those are really inspiring.

What I said about High spectrum is not from my personal experience, those are the information I got to know from random web pages so it need not to be true.
So if you say those displays are not harmful since they have the ability to filter those harmful radiations then I will say "Is it?, I was not knowing it"
Anyways I keep the brightness of my displays to the lowest since I get very irritated when my eyes are exposed to lights.
In my mobile I use Lux Lite Dash APP for reducing the brightness. So even if it is harmful it might not affect my eyes much

I wont agree to that. They wont get BANNED in near future even if it is found to be harmful.
Examples,
1)Mercury in Fluorescent lamps. They might not harm our eyes like those LEDs, but still they are harmful when it is mishandled.
2)Transfat present in almost every chocolates: Which can cause heart diseases , poor immunity, infertility etc. We know a good numbers of present generation are really suffering to have babies. and still it is not BANNED.

You seem to have misinterpreted the concept of the light spectrum and it's various components. The 'blue band' simply refers to the group of frequencies perceived by the eye to be between cyan and violet, it is just one component of white light. This is not even a particularly harmful range as the energy is still not excessively high. The harmful type of radiation is Ultraviolet (Not visible to the naked eye). This radiation is emitted by all light sources, the only issue being that only some types are adequately shielded with a UV blocking glass.

Also, the LED displays used for consumer electronics do not use bare LEDs. These simply use LED backlights instead of CCFL ones, and the layer of liquid crystals over them is retained. The phosphor coating of the LEDs in this application cuts out UV frequencies, so that does not pose a threat. It is possible that viewing LED displays can be strenuous due to the more sharp contrast and vivid colour, but this has nothing to do with radiation.

Hi Viru,

I think you are not aware about the new studies on blue and violet lights. Have a look into it.

 

[bhvm]

@Kitchu,
Most people don't understand the difference between Wrong product and Wrong Ergonomics. Even if a High Quality/Low Radiation display will cause Eye fatigue after all day use. You are just stretching the human body to limits and there's nothing wrong with the Products. Same with Meds, They can be Lifesaving under trained hands, but cause fatality in Overdose,wrong use.

I am not against bright lights. I love bright lights. I am against morons who have the Money to get them but no brains about how to use them. Even a 50W Factory high beam is very blinding if flashed to an oncomer in city.

+1 to your Dimming solution, Even I do the same.

@ Yogi, i must thank you for the thread. It has provided a chance for newbies to learn a thing or two about this newcoming tech.

@everyone
Let me add some efficiency numbers to give you a good idea-

Incandescent Bulbs (Inc'l Car headlights) are simply Room heaters with Some light output by mistake. Their efficiency are as low as 12 Lumen per watt or 20 Lumen per watt. In easy terms, If we provide 100W energy to bulb, only 20 watts are the light output, and 80 Watts are waste heat output! (this is not scientifically correct but it helps you understand)

Here are some numbers-
Incandescent Bulbs- 10~20 LM/w
CFL- 40~60 LM/w
Linear Flouroscent (Tube light) 60~80 LM/w
HID , Metal Halide- 70~90 LM/w
LED- 100~208 LM/w
Stars like Sun, Orion, Canis majoris- Approx 683 Lumens per watt!

LED Efficiencies

 

[bhvm]

Just thought I might as well show my Homemade LED lights. These are used in my office and Workshop. They're designed for 12v DC, and I use my inverter battery with dedicated wiring for the same.

The last pic is a very old design from my school days (12~13 years old)

P.s- pardon for repeated post, Could'nt find the edit button.

 

[Kichu]

Here is a 2 year old DIY of LED lamp which can be plugged directly into the AC main.
17 LEDs are mounted on a blown CFL lamp casing.
Power consumption is less than 4 watts and it gives a decent amount of light.

 

[bhvm]

Here is a 2 year old DIY of LED lamp which can be plugged directly into the AC main.
17 LEDs are mounted on a blown CFL lamp casing.
Power consumption is less than 4 watts and it gives a decent amount of light.

that's a lovely DIY!
however from now on, stay away from 5mm leds as they don't last as long. I'm using high power 1w led since 10 years now.

 

[Kichu]

that's a lovely DIY!
however from now on, stay away from 5mm leds as they don't last as long. I'm using high power 1w led since 10 years now.

Thank you bhvm Yea, that is the reason why I said earlier that your DIYs are really inspiring.

This is 8mm LED. Yes 5mm dont last much, I had similar kind of 5mm led lamp before. The reason for working with 5 and 8mm leds why because,just recently I have started doing LED DIYs, so initially decided to start with low budget leds

Here is the another simple DIY with 1watt LEDs

Three HighPower 1watt White LEDs and driver brought from ebay.
Got aluminium channel from the junkyard and cut into required length and provided it as heat sink for the LEDs.
Right now its in uplighting setup which is placed over the cupboard in the dinning room.
Obviously its not bright as our regular cfl lamps, but still this 3W LED lamp serves the purpose.
May be after a while I will try to make it into a downlighting setup and will also provide some reflector for the better illumination.
Thanks for watching

 

[bhvm]

Thank you bhvm Yea, that is the reason why I said earlier that your DIYs are really inspiring.

This is 8mm LED. Yes 5mm dont last much, I had similar kind of 5mm led lamp before. The reason for working with 5 and 8mm leds why because,just recently I have started doing LED DIYs, so initially decided to start with low budget leds

Here is the another simple DIY with 1watt LEDs

Three HighPower 1watt White LEDs and driver brought from ebay.
Got aluminium channel from the junkyard and cut into required length and provided it as heat sink for the LEDs.
Right now its in uplighting setup which is placed over the cupboard in the dinning room.
Obviously its not bright as our regular cfl lamps, but still this 3W LED lamp serves the purpose.
May be after a while I will try to make it into a downlighting setup and will also provide some reflector for the better illumination.
Thanks for watching

Great Going bro!
It looks like some Night lamps i've made in college years.

1)For your downlighting, Special lenses are available in Lamington Road, bombay which will solve all your problems.
2)Even 8mm LED will not last long. Also these plastic LED have very poor efficiency like 40LM/W. The reasons are same- No heatsinks. The LED die is encased in plastic which traps heat inside the die.
3)Another trick i've used since long is to De-rate the LED.
1 W LED (300mA) should be used at 150mA (or half watt)
3W LED (700mA) Should be used at 500mA (2 Watts)

These trick will GREATLY extend the Life and Colour quality of LED. Also Chinese manufacturers tend to exaggerate the ratings so, the commercial 1W LED are actually half watt LED. Driving them at full 1W will cause overheating and failure.

4) Using scrap Aluminium for heatsink is the best idea. I do the same in all my setups.

 

[ram123]

Looking at all the discussion I had few points,

1) led is a great technology and is far better than any other available
2) LED provide more light per wattage than any other lighting device
3) Light spectrum which we should use requires a debate and tests
4) Heat dissipation should be handled properly
5) They are useful in Automotive application but the light should be sufficiently diffused/refracted so it is not harmfull for eyes
6) There should be regulation for LED use in automative application rather before it get banned like window glass tint

 

[Kichu]

Great Going bro!
It looks like some Night lamps i've made in college years.

1)For your downlighting, Special lenses are available in Lamington Road, bombay which will solve all your problems.
2)Even 8mm LED will not last long. Also these plastic LED have very poor efficiency like 40LM/W. The reasons are same- No heatsinks. The LED die is encased in plastic which traps heat inside the die.
3)Another trick i've used since long is to De-rate the LED.
1 W LED (300mA) should be used at 150mA (or half watt)
3W LED (700mA) Should be used at 500mA (2 Watts)

These trick will GREATLY extend the Life and Colour quality of LED. Also Chinese manufacturers tend to exaggerate the ratings so, the commercial 1W LED are actually half watt LED. Driving them at full 1W will cause overheating and failure.

4) Using scrap Aluminium for heatsink is the best idea. I do the same in all my setups.

Yea, I got to know about those lenses from one of your LED Headlight DIY post untill that I was unaware about lenses for 1watt LED..

I resides in the state Kerala, here in my neighboring towns I did't found any lenses for the same. So I may need to get it online. Do you remember the cost for a lens? Just want to get a rough figure.

Ya, for this reason i don't drive them at its peak current. I just feed them 15-18ma.

Bhvm, I'm thinking about making a lamp with 68nos of 8mm leds connected in series. Which can be directly connected to our 230v house connection.
My aim is to achieve less power consumption lamp with better lumens.
Power consumption will be 230v x .018A = Less than 5Watts.
Lumens will be 20lm x 68leds = Around 1300lm
I think this can be made for around Rs.500 and may last for about 3-5 years, what say?

Thanks for the tips bro

 

[bhvm]

Yea, I got to know about those lenses from one of your LED Headlight DIY post untill that I was unaware about lenses for 1watt LED..

I resides in the state Kerala, here in my neighboring towns I did't found any lenses for the same. So I may need to get it online. Do you remember the cost for a lens? Just want to get a rough figure.

Ya, for this reason i don't drive them at its peak current. I just feed them 15-18ma.

Bhvm, I'm thinking about making a lamp with 68nos of 8mm leds connected in series. Which can be directly connected to our 230v house connection.
My aim is to achieve less power consumption lamp with better lumens.
Power consumption will be 230v x .018A = Less than 5Watts.
Lumens will be 20lm x 68leds = Around 1300lm
I think this can be made for around Rs.500 and may last for about 3-5 years, what say?

Thanks for the tips bro

Hello Kichu,
The lenses cost 10~15 A piece. They're available in Various strengths. 8 degree is the sharpest one with long distance. 90 Degree offers Smooth, Wider illumination.

I've burnt the midnight oil figuring out a Direct AC mains LED circuit, And by all intents and purposes, its not worth it-
1) Working with Mains AC is very dangerous and cause death as well.


2) Since the 68 LED will be in series formation, A single failed LED or Loose solder will take down the whole link. Troubleshooting this is a Pain due to reason 1

3) Since India is Plagued with Voltage Fluctuation and Frequent Black outs, The LEDs will fail in few months due to all this abuse.

Today, commercial 1W LEDs are available for as little as 10~15 a piece. I feel about 20 of such LED on a Metal heatsink will easily discharge 1500~1800Lumens. As the Life of 5mm LED is 12~13 years or more in My projects, Properly heatsinked 1W LED should last 50~60 years.

 

[Kichu]

Hello Kichu,
The lenses cost 10~15 A piece. They're available in Various strengths. 8 degree is the sharpest one with long distance. 90 Degree offers Smooth, Wider illumination.

I've burnt the midnight oil figuring out a Direct AC mains LED circuit, And by all intents and purposes, its not worth it-
1) Working with Mains AC is very dangerous and cause death as well.

2) Since the 68 LED will be in series formation, A single failed LED or Loose solder will take down the whole link. Troubleshooting this is a Pain due to reason 1

3) Since India is Plagued with Voltage Fluctuation and Frequent Black outs, The LEDs will fail in few months due to all this abuse.

Today, commercial 1W LEDs are available for as little as 10~15 a piece. I feel about 20 of such LED on a Metal heatsink will easily discharge 1500~1800Lumens. As the Life of 5mm LED is 12~13 years or more in My projects, Properly heatsinked 1W LED should last 50~60 years.

I thought lenses are damn costly.
Is there any online shop from where I can get those lenses? I think ebay.in dont have them.

1)Ya working with AC MAIN should requires too much care. Since I'm very much scared of getting electric shock, I make it 100 times sure before working on it. There were times that I carry unplugged fuses from the MAIN Board in my pockets

2)When troubleshooting, I just make them offline and will start working them with 12vdc battery/adapter. Since led can start glowing with a minimum of .8v, I can troubleshoot them by making them 5 to 6 sections with 12vdc source. and later can go ahead with multimeter. Simple, if we are interested to do it

3)Ya that is true, since my home belongs to rural area here we can experience frequent problems with the electricity. But still few months are too low man. My 8mm LED lamp is going to be 2 years in 4 more months. Whats the advantage is, even when my CFL lamps fails to glow with low voltage situations, my LED lamp glows :)

When I get 1 watts led for Rs.10-15, I will get 8mm led for Rs.2-3.(That means almost 5 times cheaper)
If I need to make 5 similar lamps(even though the spec sheet says 8mm will last more than 75000 hours, ie more than 40years with 5 hours daily usage) for the usage of next 60 years, production cost will be same of less. The only problem is I have to make it upto 5 times when all the LEDs completely fails(But still the chances are very less, isn't it?).

The reason for thinking about this project is as I said mentioned earlier because of this lesser power consumption.
Ya 20nos of 1watt led will results 1800lm against the 1300lm of 68nos of 8mm LEDs, but have you calculated the power consumption for the 60 years?

Consider the usage, daily 5 hours for the next 60 years.

Power consumption for 68nos of 8mm LED lamp is 5watts
Daily: 5W X 5Hours = 25watts
Yearly: 25W X 365days = 9125watts
For 60 Years: 9125W X 60Years = 5,47,500 WATTS

Power consumption for 20 1watt LED lamp is 20Watts
Daily: 20W X 5Hours = 100watts
Yearly: 100W X 365days = 36500watts
For 60 Years: 36500W X 60Years = 21,90,000 WATTS

I may try to make this 68nos of LED lamp when I get a good efficient desgin and enough time to mount these 68nos of LEDs. :D

 

[bhvm]

haha! Your Post made me smile! My Replies in BOLD

I thought lenses are damn costly.
Is there any online shop from where I can get those lenses? I think ebay.in dont have them.

I visit bombay like every 6 months or so buy little DIY and household stuff. You get tons of variety and prices are cheap. Try Farnell India website. They're very expensive and I don't know if they ship to your place.

LEDs - High Brightness / High Power Single Colour (Over 75mA) | element14 India | Results


1)Ya working with AC MAIN should requires too much care. Since I'm very much scared of getting electric shock, I make it 100 times sure before working on it. There were times that I carry unplugged fuses from the MAIN Board in my pockets

Thats the best!
2)When troubleshooting, I just make them offline and will start working them with 12vdc battery/adapter. Since led can start glowing with a minimum of .8v, I can troubleshoot them by making them 5 to 6 sections with 12vdc source. and later can go ahead with multimeter. Simple, if we are interested to do it]
Good idea. But Still a Pain to troubleshoot.
3)Ya that is true, since my home belongs to rural area here we can experience frequent problems with the electricity. But still few months are too low man. My 8mm LED lamp is going to be 2 years in 4 more months. Whats the advantage is, even when my CFL lamps fails to glow with low voltage situations, my LED lamp glows
I had some of my LED projects blow up due to voltage Fluctuations .
When I get 1 watts led for Rs.10-15, I will get 8mm led for Rs.2-3.(That means almost 5 times cheaper)
If I need to make 5 similar lamps(even though the spec sheet says 8mm will last more than 75000 hours, ie more than 40years with 5 hours daily usage) for the usage of next 60 years, production cost will be same of less. The only problem is I have to make it upto 5 times when all the LEDs completely fails(But still the chances are very less, isn't it?).

The reason for thinking about this project is as I said mentioned earlier because of this lesser power consumption.
Ya 20nos of 1watt led will results 1800lm against the 1300lm of 68nos of 8mm LEDs, but have you calculated the power consumption for the 60 years?

Consider the usage, daily 5 hours for the next 60 years.

Power consumption for 68nos of 8mm LED lamp is 5watts
Daily: 5W X 5Hours = 25watts
Yearly: 25W X 365days = 9125watts
For 60 Years: 9125W X 60Years = 5,47,500 WATTS

Power consumption for 20 1watt LED lamp is 20Watts
Daily: 20W X 5Hours = 100watts
Yearly: 100W X 365days = 36500watts
For 60 Years: 36500W X 60Years = 21,90,000 WATTS

I may try to make this 68nos of LED lamp when I get a good efficient desgin and enough time to mount these 68nos of LEDs. :D

The 8mm LED at 20mA is around 60mW. Efficiency is 40LM/w. Price RS 2
Lets consider 1W LED is actually 1W. Efficiency is 100LMw Price 10~15


To Each 8mm LED- 2.5 Lumens. To attain 100 Lumens- 40 LED needed.

Cost- 8mm LED- 80 Rupees
Cost High power 1W- 10~15 rupees.

Do the math. Use 5 or 10 high power 1W led if you don't need 1800 Lumens. I am damm sure it will be cheaper and better than Plastic LEDs.
Add a Dimmer before transformer for dimming as when needed. I feel its bettter to Make a bright Light and Dim it out when not needed. I Made a 5000 Lumen Lightbar for my hall and it can be tuned as when needed. When guests arrive, we can run the Lightbar on Full Blast. An 80W PWM Type Fan dimmer seems to work well with Transfromers.

 

[Kichu]

haha! Your Post made me smile! My Replies in BOLD



The 8mm LED at 20mA is around 60mW. Efficiency is 40LM/w. Price RS 2
Lets consider 1W LED is actually 1W. Efficiency is 100LMw Price 10~15


To Each 8mm LED- 2.5 Lumens. To attain 100 Lumens- 40 LED needed.

Cost- 8mm LED- 80 Rupees
Cost High power 1W- 10~15 rupees.

Do the math. Use 5 or 10 high power 1W led if you don't need 1800 Lumens. I am damm sure it will be cheaper and better than Plastic LEDs.
Add a Dimmer before transformer for dimming as when needed. I feel its bettter to Make a bright Light and Dim it out when not needed. I Made a 5000 Lumen Lightbar for my hall and it can be tuned as when needed. When guests arrive, we can run the Lightbar on Full Blast. An 80W PWM Type Fan dimmer seems to work well with Transfromers.

Thanks for the link Bro, Let me go through it.

That means 68nos of LEDs will yield only 68*2.5lm ie only 170lm?
Hahaha.. I misunderstood it as 20lm per 8mm LED

Really thanks for pointing it out and also for providing the correct information.

Wow, 5000lumens. I wish to do similar kind of LED lights for my hall, but the problem is I'm sure about how good will my DIY Lamp looks from exterior :(

Once again thanks a lot for correcting my mistake. :)

 

[bhvm]

Thanks for the link Bro, Let me go through it.

That means 68nos of LEDs will yield only 68*2.5lm ie only 170lm?
Hahaha.. I misunderstood it as 20lm per 8mm LED

Really thanks for pointing it out and also for providing the correct information.

Wow, 5000lumens. I wish to do similar kind of LED lights for my hall, but the problem is I'm sure about how good will my DIY Lamp looks from exterior :(

Once again thanks a lot for correcting my mistake. :)

Home made LED lightbar will look Cool. It looks Futristic and 'hat ke' design. People ask and comment all the time- "wooW what's that? You made that?, kya cool hai yaar!" and It feels very good. Do not worry much about external looks. It will look best. Good luck. Scroll up a few posts and I have posted my LED lightbar pics. I think previous page or so.