Introduction: LED Projector Lamp V.1.0

Picture of LED Projector Lamp V.1.0

My first video projector. Ever.

Last year I came across a cheap Toshiba TLP T70M projector on some e-bay wanna-be site over here in Romania. It had no lamp at all but other than that it was operating properly (or so the salesman told me). I traded it for a Shuttle computer I had in my closet and in a few days the projector was delivered. I was surprised that it was in a good condition, I was expecting cracks and scratches, it had none. I turned it on and - predictably - the “lamp missing” LED came on in about two minutes. At this point the projector shuts down automatically. During those two minutes I was able to see the startup screen by looking thru the lenses while holding a small flashlight where the bulb was supposed to be. So yes, it was operating.

I started google-ing all I could find about this projector. I came across the complete Toshiba TLP T70M  user manual (it had none when I received it) and that’s about all. At this point I wasn’t really decided what to do, I was tempted to buy a light bulb for this model and use it as anyone should. On the other hand being horrified by the huge price that projector bulb had it was clear I had to find an alternative light source. Me being a LED addict I started thinking about that. It was the obvious choice but the problem will be the light output. The projector’s lamp had 2000 lumens and in “eco-mode” had 1000 lumens. I was aiming for his lower figure as I won’t be using the projector in daylight anyway. So my goal is 1000 lumens of LED light.

Insert a few weeks of random ideas and pointless calculations here. Lazyness, to be more precise.

Step 1: Parts Used

Picture of Parts Used

I decided I will buy the most powerful LED I can get my hands on and try to use it as a light source in my projector. All this without being distructive or making irreversible changes to the projector. Google that and it turned out my only choice in power LEDs (over here, in Romania) was a Cree MC-E M, Star, White, 752 lumens output, 4 chips, 110 degree (light beam). I was hoping for a OSRAM OSTAR rated 1000 lumens but the reseller couldn’t provided it.

The original projector lamp had 2000 lumens and 1000 lumens in eco mode. I figured if I get close to that eco-mode it might be usable in my tiny apartment. This LED is rated for 50.000 hours of operation and is considered equivalent with a 75W incandescent bulb. I also ordered a 700mA constant current power supply to power it. This one is rated up to 30V DC output @ 700mA and is powered by grid power (220V AC here). I plan to hide it inside the projector once the project is successful. But enough daydreaming.

Step 2: Electronics Involved

Picture of Electronics Involved

The first step was to fool the electronics into thinking the lamp is present so that the projector will start operating properly and get rid of that automatic shutdown. A few Google days later I came across a French site on the very same subject. It turned out all I had to do was to find a logic signal that was up (5V) during the first two minutes and down (GND) just before the LED missing indicator turned on. I found it eventually, using my multimeter. By pulling this signal up (a simple wire jumper connected to a 5V source I found on the board) it started normally thinking the lamp was present and on. I connected a laptop to it and checked that the movie was playing by looking into the lens while holding the same flashlight inside the projector. Yes! I was glad I did this, I’m not that experienced in electronics and I feared I may end up stuck at this stage.

Step 3: Construction

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I ordered the LED and used a heat sink I had around from an old Pentium I. As space is an issue, I had to make sure the LED bulb will fit. This heat sink was the only choice. The LED came mounted on a small star heat sink so I drilled two holes for the screws in the Pentium heat sink to attach it firmly in place. Arctic Silver 5 thermal compound was used in between those parts. After wiring the LED (the four chips had to be connected in series first) I scavenged a flashlight for the light reflector. Inside that I put a 45 degrees matte lens I also ordered in order to make the light more focused and uniform as the four chips are not a single light source but four, close to each other. I also used two PCB boards I cut to make the bottom and the top of the light bulb. This was needed to make sure the bulb wouldn’t move inside so I cut them to the exact shape of the existing space.

Step 4: Testing the Bulb

Picture of Testing the Bulb

The bulb was powered using a 700mA constant current power supply. As each chip needs 3.5V@700mA the measured output was 14V@700mA. That’s 9.8 Watts... my mind instantly told me it’s not going to be enough. But we’ll see. Anyway, it’s well below the max 30V this power supply puts out. I was a little worried about the amount of heat but as it turned out the heat sink barely gets warm, thanks to the built-in fan this projector already had for cooling the bulb.

In this picture you can see the bulb, the flash light made its light beam look weak but trust me, it’s strong and blinding if looking directly to it. It’s not recommended either, actually.

I mounted the bulb inside and proved to fit perfectly. I used the original bulb mounting holes. First tests, as you can see were indeed, disappointing. This projector being a LCD-type (unlike the better DLP ones) proved to eat up about half of the LED light output when displaying anything. This I wasn’t expected. Lack of experience and knowledge, I guess. I was quite disappointed finding this.

Step 5: Conclusion

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In a completely dark room I was able to watch “Avatar” but the dark scenes were too dark. As you can see, the scenes that were full of light were almost viewable but that’s about it. It’s clear that I need AT LEAST a double amount of light. 750 lumens is nowhere near enough. Besides, not having a luxmeter I suspect that only half of that reaches the screen. It was fun nevertheless to play with a projector for the first time. I like it and I’m determined to use it. Time to get back to the drawing board. I need more power, more light, all within the same confined space.

Step 6: To Be Continued

Picture of To Be Continued

Months passed and I still look for a better LED. I decided to try a second version of this light bulb. This one will use an array of 9 x NS6W183T Nichia LEDs. Rated at least 225 lumens each, I should have in excess of 2000 lumens of light. If 1000 lumens of those do reach my projection screen I will be happy, that’s the “eco mode” I was hoping for. The main issue with this attempt is that I have to keep the light source as small as possible while focusing it on that Fresnel lens inside the projector that’s 3x3 cm small. Oh, and the entire LED bulb has to fit a 5x5x9 cm space. Small space for serious power and an estimated 35 watts of dissipated heat. But I won’t give up. Look out for my next instructable on V2.0 once the 9 LEDs array is ready. Right now we’re about to have a baby so it’s standby for everything else. J

Thank you for reading this. Feel free to ask any questions, I’ll try to answer them.

Edit: our baby was born today! I'm the proud daddy of a very cute little boy!


harikr54 (author)2016-09-26

hi i have my projector with 2000 lumens can i increase lamp capacity to get 4000 lumens. Mine is 220v 230w lamp as of now.

SamuEDL (author)2016-07-24

Might you do a photo of the bridge of wire? It is that I have not still had it very clear, I have the same projector. Sorry my english

JohnM778 (author)2016-05-09

Nice post friend.I bought a panasonic pt ax100u projector which has a bulb expected to live around 800 hours around 700 it started to shut off once then have to be turned on and worked fine...well after 4 months later and having to turn the darn thing on 5 times before it stays on im curious as to if its a bulb issue or something else.

for more details:

claudiopolis (author)JohnM7782016-05-10

Thanks. You do have a bulb issue. The gap between the bulb's electrodes got larger (that's the actual wearing of the bulb, the electrodes slowly consume themselves) and the power supply circuit cannot sustain the power needed to generate the electric arc. The protection kicks in and you have a lamp in need of replacement. The on and off thing works for a short time, but the end of that lamp has come. Replace it or convert your projector to a HID lamp. You'll need a shunt on the mainboard to fool the projector the lamp is fine, a HID ballast, an external PC power supply, a modified bulb .... it's doable but definitely NOT for the average user. Oh, and it's a major violation of warranty terms :-)

AtosM (author)2016-02-05

hi, LED light is a super idea. how about testing the projector with a cheap strong LED torch like this one on eBay: 3000 Lumen Zoomable CREE XM-L Q5 LED Flashlight Torch Zoom.

Good luck...


claudiopolis (author)AtosM2016-02-07

Hi there,

No, I haven't. I wish I would. However, I doubt it will last. I tend not to trust Chinese overpowered LED items. I just don't see it lasting hundreds of hours on external power supply.

Never trust chinese figures on Lumins or battery specs..they all come far below listing..Ebay is becoming a platform for Chinese fraudsters. After years i am trying to break free from Ebay and paypal..both team with scammers.

goldenshuttle (author)2016-05-05

Great post and funny comments..especially when u mention the day dreams n laziness virus which all DIY people have..great post thumbs up.

mopowah. (author)2016-05-03

I have done this before ran into an issue though the light I got was massively bright and hot melted the case and the color wheel never really messed with the type of light I purchased before but hoooo man you want to talk about blinding light this thing was insane.

On a side note a typical 100wat bulb is 1600 lumens ... But I think the fella that had the idea from the car light hit it right on the money... Anyhow your post is fairly old and LED has come a long way since then so I am sure you have found the way... Easy way to find the circuit to trick is look for two optocouplers actually often you can just trace these out and just cut and splice wire that is there to make it work.

Anyhow I enjoyed your posting a bit nostalgic for me ;)

light86 (author)2015-07-29

hi, I am John from China,nice to meet you.

bogdan.dumitru.9674 (author)2015-03-24

Just use a 4300 k cheap ebay 35 w Xenon bulb powered by a cheap ebay ballast (14V input) that are made for car xenon retrofits. It will cost you about 30€ and the best part is it doesn't need any heatsink.
LEDs have a long way to beat that still.

... There is also a choice of getting a 55w ballast. The xenon bulb stays the same. Light output is about 30% greater than it is with 35w ballast.

leo.tsattalios (author)2015-03-15

Hello all! I have the CL312A LED Projector that I bought from Ebay. After a year of usage, suddenly one day it stop producing image but only sound. I guess I need a lamp/bulb replacement. Though, there is nowhere inside the manual any instructions on where is the lamp or how I can replace it. Could anyone please help me with some instructions pleaseeee????????????

mathewriver (author)2015-02-02

Congratulations for your son's birth!

rushabhpathak (author)2014-02-27

I have your lumen solution.

I would go with the 50 watt bulb. You will definately want a bigger heat sink too

spiffly (author)2013-12-11

I think you're making a mistake with your lumen comparison here. The advertised lumen output for a commercial projector is referring to the final light output from the unit, not the raw lumen output of the bulb, so if you put a 752lm LED into the projector, you'll likely get between 10-30% of that after the light has passed through all the apparatus, much lower than your target of 1000lm.

claudiopolis (author)spiffly2013-12-11

You are right. I learned this the hard way. That's why I stopped developing any projector LED light bulb. DLP projectors are better as those won't take that much of the light output. But with LCD ones, it's a painful experience.

sk8er6 (author)2013-11-11

Hey great instructable. Thanks for covering the issue in fooling the projector to think the lamp is present. I have a Mitsubishi SD205U gathering dust in my closet, so Im going to give this thing a shot. Really awesome write up, clever use of PCB. A more abundant, brighter, and more inexpensive light source can be had with a car headlamp. Someone else had wrote up an 'ible on it,

Seems like the way to go, reading the comments and the 2.0 write up.
I'm heading out for supplies for this as soon as I get off work!

jduffy54 (author)2013-07-13

If you want some serious firepower, I'd suggest DX's 50W LED,
its $27 and should meet or beat the original lamp.

claudiopolis (author)jduffy542013-07-14

And I'd suggest you reading the v.2.0. instructable.
Focusing LEd array properly is next to impossible. with DIY stuff.
And I have bought a 30W LED from them. Guess what, same problem. Not the light output was the problem but the fact that you can't focus it.
The original lamp can be beaten by LED arrays in lumens output but as a truly focused beam of light nothing else comes close.

jduffy54 (author)claudiopolis2013-07-14

Au contraire, it is very easy to make focused lights. You mentioned a reflector, but didn't seem to considder re-using a parabolic one (such as those from lantern flashlights). You also stated that "Lens[es] are useless here because I have 9 separate light sources spread on a 2x2 cm" However, you seemed to ignore that you COULD use a diffuser in front of the leds, and use a compound lens for a reduced focal length (such as I can guarantee this method works (even using sanded acrylic as a diffuser) because I've done it (though with a different lens).
Also, most of the projectors I've seen only put light through a small hole (or lens, in your case), so simply putting reflective material like mylar or polished aluminum (you did mention an aluminum reflector in V2) around the LEDs and right up to the hole should give almost no light spill. I dont see how you could have a significant light spill if you just made it to adapt directly to the fresnel lens with reflective, solid material.

claudiopolis (author)jduffy542013-07-15

Ok then, you asked for it.

A high power LED is usually square in shape. Any round parabolic reflector should be cut extensively to have the entire LED array fit properly. Bye-bye focal point, you can not achieve that anymore. The high-power LED arrays, when operating, get very hot, to the point of melting just about any parabolic flashlight reflector you might re-use for that. So you must go for metal ones. Let's not mention the glass option, it's almost impossible to cut properly.

The metal reflector would work but we'd have another problem. It's metal, so if by accident touches the LED array pins you will burn you power supply. Spectacularly, I might add. But let's say that doesn't happen because we leave a gap between the two. Light spills out - a lot. Why? Because you also used a diffuser after the reflector and it's also, very reflective. Compound lens take up space you do not have inside a projector and you loose light with any lens or diffuser you place in front of the LED array.

In my video projector I have 12x6x9 cm to fit the bulb. Anything bigger will stick out of the case. Your proposed setup would be bigger than that. Along with an external power supply or power brick, it'll look ugly. But I'd get over that, if the goal would be reached.

If none of the above seems major problems, let's talk about the final one. Heat. As you know, I presume, LED arrays are to be cooled correctly otherwise they would shift their color temperature and fail quickly. Especially the DX-purchased ones (man, those Chinese have horrible manufacturing quality). The surface of the LED array must not reach 104 degrees Celsius or it will burn itself. This can usually be avoided with big CPU coolers and stuff but the LED array itself is trapped between a parabolic reflector and a diffuser. There's no way to cool that. Heat will build up in there. My projector has a dedicated fan to cool the front of the original bulb. I tried to use it. The reflector got in the way. Without it, massive light spills. Oh, well...

My advice: Get a high-power 150W LED array. Go to a 3D specialist and pay him to come up with a 3D project for a water-cooled metal reflector and cooler, small enough to fit inside the projector case. Go to a manufacturing facility and pay them to make you that 3D part in copper or aluminum. Then fit your LED array inside the reflector, connect the water-cooling hoses, the external power supply and you might get a long lasting LED projector bulb (Provided the DX shop sells you good stuff). Then sum up your bills and come up with your own conclusion. Mine was that it's cheaper to buy original bulbs. And it looks nicer. And I don't have to worry that the power supply I got from DX will burst in flames.

jduffy54 (author)claudiopolis2013-07-15

I told you above, I have already done it! Unless someone implanted a false memory in me as well as the person whose projector it was, as well as replacing that lamp with an led lamp as I would have designed. I didn't use a reflector, but did use the others, except the led, for which I used an xm-l. even at a third the power of yours, it was reasonable.

claudiopolis (author)jduffy542013-07-15

Ok then. Let me guess, that was a DLP projector, right? Those have much smaller light losses. Mine is a 3LCD type. Lots of lens and screens for the light to get thru.

callen36 (author)2013-06-30

Not quite a failure, it was very informative. The current LED bulbs in the market have high lumens rating and might be usable here. This article shows how to disassemble a typical LED bulb

claudiopolis (author)callen362013-07-01

Well thank you very much! I do keep an eye on LED bulbs on the market. What I'm seeing is a rise of LED arrays inside those bulbs. So it's not that LED's actually get brighter. Instead, the high-lumens bulbs feature several LED's. Yesterday I just disassembled one. It started turning on and off repeatedly. I thought one of the capacitors went bad but that wasn't the case. One of the LEDs (there were three in a serial array) started to die (overpowered array, what else could you expect from China). I bypassed that LED and the remaining two are going well for their short remaining life.

Back to projector lamps. Best result - and the only result I'm after - is to use a single light source. You'll be able to use the original bulb reflector and the light will be much better focused. The problem is that a single light source when using LEDs is just not strong enough.
Using LED arrays is not the way to go. I would rather try a xenon lamp instead, those French guys on are having great results using them. And those lamps are cheap, too.

biolethal (author)2010-12-17

found something crazy on ebay... a 100w led. supposedly has about 8000 lumens output.  link

claudiopolis (author)biolethal2010-12-20

Thanks, I saw that one a while ago. Too much heat to get rid of, too much power draw, requiring a beefy power supply. And you don't really need that many lumens anyway. Around 3000 would be enough, I say.

biolethal (author)claudiopolis2010-12-20

yep. it would be cool though.

claudiopolis (author)biolethal2010-12-20

Actually it would be hot. Real hot. 90W thermal dissipation is way more than a PC processor puts out. Imagine the cooling solution needed. Put that aside, just consider the fact that your projector might just melt due to the intense light beam this 7000 lumens LED puts out. You know, projectors are mainly plastic....

biolethal (author)claudiopolis2010-12-20

oh. misscommunication... i meant figuratively cool, not physically cool. :) maybe with a temperature switch and variable dimming of the led it might work.

I bought the 100w 8000lm LED chip on ebay. it came with a power supply, lens and reflector for about $60. The heat shouldn't bee too much of a problem. the original bulb was a 100w bulb was just as hot. A heat sink is absolutely needed and do not run it with out the fans of the projector on. So far i have not had a heat issue. the picture is not the brightest but it is 100% better than my previous 2000lm bulb. I will be putting up an instructable of my build soon (by the end of the year).

That sounds awesome!

I have finished the the write up. Here it is:

Looking forward for that one. I envy you. :-)

kokyay (author)claudiopolis2011-08-30

it all depends on the led, most led's don't give out the UV light. it is mainly the UV light that makes the light beam hot.
this causes a lot of problems in some poorly designed projectors and TV's because the light destroys the panels. if you use a white high power led and it should work fine. leds are considered very efficient.

takeouup (author)2012-02-22

how did you get the projector to stop shutting down without the right bulb . how does it know the bulbs is bad , is it volt/watt usage of the bulb or the brightness of the bulb . i tried to use 120v 100w bulb it comes on , lights up , but still says replace bulb and shuts off. any help would be appreciated . thanks for your time.

Most projectors send a logic signal to the main board that tells it that the bulb is either missing or needs to be replaced. Use a multimeter to check the wires that are connected to the board. If there are any labels on the board use those to try to figure out what each wire is for. You will most likely find a wire that is either 5v or 0v when the projector turns on and then switches to the opposite voltage when the "replace bulb" message shows up. How familiar are you with digital logic?

First, I'd try resetting the bulb-hour counter. Some projectors use that as a first layer of protection. Then, as invisiblelight386 wrote, you need to find the wire responsible for shutting down the bulb's power supply. Hook the black lead of your multimeter to a ground point on your board.
With the red probe touch (one by one) the connections of the signal wires. Those are easy to spot as there are 3/4 or five thin wires (or flexible strip) going into the power supply. The power wires are much thicker. Measure the voltage on each wire with the projector on, just before shutting itself down. You'll notice one of them shows 5V before shutting down and as the power supply shuts down, that wire will show 0V. Mark that wire and go find a permanent 5V source on your board (using the same red probe). Usually around the small power regulators. Once you find it, solder a wire there and solder the other end to the wire that goes 0V when shutting down. Having a permanent 5V there tricks the board into believing the projector bulb is on and the boot sequence goes on as normal. Use your 120v bulb to discover you'll hardly see anything on your screen :-). That burnt projector bulb was way stronger than that.

goldenshuttle (author)2012-05-05

Nice work Claudio...I have bought a dead Sanyo projector with missing bulb. not sure if it was the bulb or other thing. bulb is costly so im afraid 2 buy it then it turns the problem from other reason....feel like wanna rip all the electronics out and turn it into LED projector.....good work buddy

Lefrançois (author)2011-11-23

i have found that on 'deal extreme'
for 16,61 € or 20,18$ freeshipping
if this can you help....

vistal (author)2011-11-06

Lamp Life: UP TO 50,000 hours

Total Watts: 96watts (32 High powered LEDs fused onto a cell Plate)
2,500 Lum
These bulbs are on ebay . Wonder now if i can get info on a conversion for a reg Projector now.:))

arnookie (author)2011-06-19

You can now buy led projector bulbs from ebay.
£36.49 + postage from here is the cheapest I found.

Copy and past that link and you can see for yourself.
I was going to do the same thing, ie buy a used projector with no bulb and make my own, But I decided to buy one of the cheap Abis projectors off ebay.
I was very supprised how good these cheap projectors are.
But be very carefull. I purchased the Abis HDpro for £200 and it has two hdmi inputs, component, composite input, vga and tv tuner input. It handles 720p fine and 1080p with compression 4.3 to 16.9 aspec ratio in all formats. Some other makes don't have all these features. It saved me a lot of hassle trying to make one work the way you have.

But if you are trying leds I would look at the cheap led projector bulbs off ebay.
Lamp Life: UP TO 50,000 hours Total Watts: 96watts (32 High powered LEDs fused onto a cell Plate) and upto 2,500 lumens.

vistal (author)arnookie2011-11-06

Thats Sweet just what i was looking for . I hate the 2000 hours on a reg bulb i wonder if i can convert my norm bulb to this style.

butterninja (author)2011-10-14

Hey all. I too am staring on a projector project and I hope to have it done by Christmas. would people be interested in basic and slowly added instructions, or would it be better to upload them in one large batch? let me know if your interested in a full instructable on this. also any suggestions on what lumen bulb to get would be great.

claudiopolis (author)butterninja2011-10-16

I always believed a fully fledged instructable is better than adding stuff as you go. That's why I post so rarely :-). My LED Projector Lamp v.2.0 is stalled right now with no real future. I might post the progress so far, maybe someone can take it from there on.

skaur (author)2011-08-26

Congrats Claudiopolis - I know its been over a year now. I wonder how everything is with your son and if any luck has happened with v 2.0?


claudiopolis (author)skaur2011-08-30

Hi skaur, thanks for asking. My son proved to be a much bigger challenge. than we ever anticipated. That's because his medical condition requires almost daily kinetic therapy. So we're back and forth between home and hospital but other than that he's just fine. Hopefuuly he'll be soon in line with the other babies of his age.

As you can imagine v. 2.0 was put on hold and still is. The project is about 50% done but I have troubles focusing the light properly. I may switch to a car xenon bulb setup, it's cheaper and compatible with the shape of the reflector in the original bulb. See for that. Cheers.

bsilva (author)2010-06-03

I'm sorry it didn't work out, but it's always useful to see reports of what doesn't quite work.   Sometimes this is more useful education.


claudiopolis (author)bsilva2010-06-03

Well, I'm not that sorry! I got to see "Avatar" on a projector! :-) For the first time.
Kidding aside, one learns a lot from failures. And I had lots of them :-))  As it is, I wouldn't consider this V.1.0 bulb a failure, it's rather insufficient. Hopefully V.2.0. will be better. I already started working on it but it'll be long before I'll turn that one ON.

About This Instructable




Bio: I am a graphic designer with many hobbies. I love electronics, computers, LEDs and all things tech.
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