Hi Adam

Where did you find your lens mount??


Niels

Designed it using parts from Thorlabs which offers excellent modular lens holders and systems. Used the B2C for mounting the lens tube to the heatsink (after tapping a few holes in the heatsink).

B2C lens mount plate
http://tinyurl.com/lenstubemount
Lens tube
http://tinyurl.com/lenstube

Nice lens holder .
I do not understand what do you mean by red,green and blue specks (my English is not that good ) but I guess are the small stain magenta, yellow and turquoise this are from the dust on the LCD's for example if you have a small dust particle on the green LCD then you will get on screen more blue and red on that point so magenta.

That sounds right as you can see the small dots on in the picture. I guess I need to clean the LCDs. Also, I actually am only getting 11 Lumens projected at 1 meter in a 10cm x 10cm square with my lens. 2 of the 6 emitters are outside the measurement of that box. Does that mean they are not being used inside the projector? Below is the "specks" I was referring to.

http://tinyurl.com/specksofdust

Sorry is hard to work with Pentium3 700MHz and 256MB Ram I hope HP will fix soon my laptop.
test Cree Q3 from 1m
11 lumen is to low you need to get 30 to 50% of the spec lumen so 1000lumen 30% is 300lumen and on 10x10cm from 1m you will need to get 300 x 100 = 30000 lux or more .
Maybe the distance between LED and lens is not right you will need about 22mm from LED to the flat surface of the lens but is better to do some test an see at what distance you get the smallest spot. hope you can get less than 10x10cm from 1m but even 12x12cm will be acceptable .

Ok, made this yesterday night. I've used some plumming pipes
Click to view attachment

Click to view attachment

Click to view attachment

Click to view attachment

Have to go to sleep now, and get up early for further testing. Hope I'll get better result with this setup. I don't have a Lux Meter, so for now all I can do is visual testing.

That is Sweet! Good job. I just ordered 2 of those lenses and will try one of them with my Ostar later on. Maybe with the larger diameter, I might get more light from the LED which diverges out at 120 degrees or so.

Think I finally have my numbers right. At 1 meter away, I measured a projected spot of 15cm x 8.5cm @ 11,000 lux. So I multiplied .15 x .085 x 11,000 and I got 140.25. I assume with my setup I am getting 140.25 lumens from the LED and lens alone. Then I measured the projected image with the LED light engine and got 51cm x 38cm @ 50 lux. So I guess my projector is putting out around 10 lumens.

Pictures look good so I am pretty happy but still need to tweak to get more out of it.

from 10lumen is starting to look good but you need to get more with your LED close to 400 or 500lumen from the LED + lens and 15cm is to much I now onstar is 6x2 but if you get this smaller like 10x6cm or less then even with the same 140 lumen you will get more out of the projector but as I mentioned before you need to get more than 300 lumen from your light source

It seems that the distance between LED and lens is to big for the best result you need to see the projection of the 4 led inside the SSC P7 so you do not need a Luxmeter I expect about 22mm from the LED to the lens but is perfect when you are able to see the projection off the LED.

Hi electrodacus

I just found out what my problem is My driver circuit can't deliver enough, and if I use a voltage regulater with 3,7V output, it almost double the light.
Click to view attachment
This is used with a 5V 3500mA power supply


Do you have the schematic diagram for your driver?

I've been thinking, if using a 100 Hz pulsing driver we should be able to push the LED further

Niels

This is not the biggest problem the lens position is.
I use simple resistor to limit the current on most of my LED's.
You are not allowed to use more than 2800mA on your LED if is SSC P7 . The schematic represent a voltage linear regulator and is not a good solution to use voltage regulator with LED's you need a current regulator with 2800mA output the one from Kaidomain is OK it using 8 x 350mA regulator .

I know my voltage regulator is not the best choice, but I'm waiting for my drivers from kaidomain, should be her tomorrow or wednesday.

What about my idea about using a 100Hz pulsing current regulator? Then the LED could use almost double current without frying it.

This do not work with the projector you need continuous light using pulses will interfere with projected image and you will have a flickery image.
This is my idea I did not tested so maybe I'm wrong it will be a good Idea If you can synchronize the image with the LED frequency but I believe is complicated to implement and I do not like the Idea of having a intermittent projection I do not like CRT I only use LCD's now
Also the reason I do not like DLP unless it 3xDLP

Take a look at this http://www.satcure-focus.com/tutor/page10.htm I've tryed that trick years ago to get more light from led's. I belive you cant see the 100Hz switching/flickering on the screen.

I also now about this and is no problem for a simple light source but 100Hz from led and 50 or 60Hz from projected image do not fit good together Is my idea I may be wrong .

You could always flicker it at a higher frequency, if the LED and power supply will switch on and off fast enough.

I think that in the end, since your eye averages the brightness over time, if the LED is twice as bright and on for half the time, it won't look any brighter. If by pulsing it, you can increase the brightness by more than 2x (that is if you have it on half the time)...then it might appear brighter?

Excellent explanation regarding High Brightness LEDs, pulsing and whether or not it helps apparent brightness by Don Klipstein:

"Note that most of the modern ultrabright LEDs have close enough to maximum efficiency at currents near or below their maximum rated current. If your average current through each LED is around or over 20 mA, use steady DC. It does not pay to pulse the LEDs when the average current is around or over 20 mA.

Furthermore, the usual ultrabright white LEDs, as well as gallium nitride or indium gallium nitride greens, blue-greens and blue LEDs of wavelength 460-475 nM have maximum efficiency at lower currents. It works against you to pulse these. Same for "low current red"/GaP red/"697 nM" red LEDs."

http://members.misty.com/don/ledp.html

His articles are an amazing resource for LED info.

The human eye is strangely react to light so if you have a 50% pulsing LED with 2x the current then even the averege is the same the eye will remain impress by the strong pulse light so it will appear brighter.
The problem I see is that the image on LCD is not a fix one and If you just take shots at different time it may be that the image is not prepared completely for the 1/100 of a second and then at the next pulse will also probably not be in the best "shape" Is hard for me to explain but in a animated image you have the pixels constantly changing the state and by missing some of the state in the period of time when LED is off you can have some sort of strange effects on the projected image.
I hope you understand something from my explanation because I' don't

I understand what you mean.

There are different theory about this but I believe it works at least according to this guys LED-pwm
But I do not think it will work with projectors at lest not in a easy way.

According to their research, they used low power ones such as the Nichia NSPB500S which puts out about 3460 mcd at 10 degrees = ~0.083 lumens. Just a little less than what we need.

Here is another discusion about the subject http://www.electro-tech-online.com/electro...-using-pwm.html

Think I'll try it.

As Electro said earlier, you will get the most gains by tweaking the lens and you might have "out of sync" activity between the LED and the LCDs but, if you want to try, good luck! Remember, you are dealing with the High Brightness LEDs which are an entirely different beast than the 5 mm ones (which is what is being referenced in these other links).

Another route might be looking into a using a "bluer" LED bin which our eyes are more sensitive to in darker situations (Scotopic Vision). Not sure though how that will interact with the LCDs and the accuracy of colors on the screen. Great example here and check out the Lumen comparisions.

Scotopic LED example

Electro, this got me thinking. When we are comparing lumen output of our LEDs in a dark room in comparison with the rated lumen output of the LEDs, are we comparing Scotopic or Photopic lumens? We might be comparing two different standards as I assume they would use different formulas. Published/rated lumens are measured using Photopic sensitivity values so the estimated lumens calculated might not be accurate (I think). (always wanted to use this "smiley")!

We mesure lux and calculate lumen and the luxmeter is more sensitive to 550nm exacly as our eye are so more lux will be more bright for our eye's or eye you can se in this older post the color output for LED ,florescent and incandescent lamp Link .

Got some more pics. from today

The first is with all light in the room turned on.
Click to view attachment

The next is in complete darkness
Click to view attachment

Pictures are taken with my cell phone (all I got right now for photos).
Size of the screen is 78", so this is a little smaler. Guess about 65-70"

Another thing, yesterday night I tried to see how much light this LED could give as a flashlight. And WOW it did light up a chuch tower 400 meters away That's so COOOOL

Looks good if you can see something with the lights on then is more then 10 lumen , maybe you can get more
It seems to be to much green on the image but is not so bad (red is a problem with the LED light‘s if the led is not red )

I didn't know that the luxmeters we were using are most sensitive to 550nm so that is good to know. Although, while it is true that our eyes are more sensitive to those wavelengths during well-lit conditions (photopic vision), I believe that is not the case in low-light conditions (scotopic vision).

http://en.wikipedia.org/wiki/Photopic_vision

I did find an actual meter that will more accurately measure light from either scotopic or photopic conditions and calculate using "different CIE action formulas" accordingly. Of course it is considerably more expensive.

http://www.professionalequipment.com/scoto...l-light-meters/

You will see in this chart the difference in our eye's sensitivity according to lighting conditions.



And according to the following link, posted earlier, you will see how the average delivered lumens per fixture is different depending on either using the scotopic or photopic formulas (that use the different CIE chart again). The LEDs which are typically "bluer" gives our eyes a greater response at night, hence higher scotopic lumens and "more light" in the parking lot there. Interesting to see the camera also as sensitive.

http://www.ledworkplace.org/PrairieSchool.htm

I have talked to the tech support guy at Luxim and he states that with their Solid State light engine, the manufactures who use their products for projectors actually prefer a scotopically optimized (slightly bluer) light source.

I guess my question is (to anyone who might know) how does that translate into an image on the screen after it passes all of the LCDs (of a commercial projector)? Is it going to be noticeably more blue with a HB LED or will our eyes adapt and have almost like a auto-correct white balance effect or will the LCD's ultimately have the most control over any color it makes? All answers are appreciated!

Unfortunately the brain will not be able to do white balance but you can use the computer or projector if you have color temperature function but this will reduce the total lumen output (ex: if you have more blue in the light source you will see this also on the image the brain will not be able to do white balance and if you use projector or computer settings to do white balance you actually cut the level of blue light that is exiting the projector by darkening the blue LCD in 3LCD projector so no gain ). The most efficient is to have all 3 color as 3 separate LED and eliminate the color filter so one LED in the back of each LCD but you will need more space than the commercial projector will offer or you can use mirrors.

LED's are verry dificult to manipulate. i am working a a laboratory and doing LED testing all day. www.spectralux.ca

they are some LED's that drive 700 to 900 lumens with an average of 70 L/W but you need a verry good heat sink.

the problem with the LED;s is that at the starting you have a hught lumen value taht decrease with time ( 1 hour normaly) it start with a high lumen value

and it stabilized after one hour ( when the temperture at the LEd jonction is at the max)

a Lux meter will not give you a lot of information. you need a luminace meter and a photometer with a colorimetric detector ( gigahertz optics have one HCT99)

a normal process is is to putt the LED in a integrated sphere to get the real lumens, cct, cri, x and y. you need the spectral power distribution to have all these values.

the test is done with a spectromter and an optical fiber.

more you putt LED on a cluster, more they will be heat and less lumens.

good job I do this as a hobby (and you are paid for this) .
I'm an electrical engineer an I worked about 5 years as a electronic engineer in automotive safety (designing airbag control units) but now I have a long vacation I will probably extended one year more so I have time for some of my hobby's.
I now that the luxmeter dose not give you complete information but is enough for what I need.
I'm quite happy with the projector .Now I just started to work with blender3d some example from my work Link I just started last week but is fun And I hope in the spring I will be able to start building my dream house second one but first in Canada and Then I will use only LED for illumination since it will be in a remote location an I will generate my on electricity so everything need to be efficient.
The projector is not so efficient since it takes about 80W comparing with my 20" LCD screen that takes only 20W but it was nice to build .

Some people here do not have even a 30$ luxmeter I do not think anyone will buy a spectrometer

Need some advice on disabling lamp detection on NEC VT 45K. I believe ive found the correct wires. 3 white and one red.

1. (red) 0v on standby , 2.7v as ballast ignites then back to 0v
2. (white) 0v on standby , 2.7v as ballast ignites then back to 0v
3. (white) 3v on standby , 3v continuous
4. (white) 0v on standby , 0v continuous (ground)

my ballast attempts to light 3 times throughout bootup before returning a red status light error then shuts my projector down.
By earthing wire 3. on bootup , it gives red light instantly , but earthing the others has no effect.
By earthing wire 1 & 2 together , the ballast stops trying to ignite
By earthing wire 3 with any of the others causes instant red light

all combinations of bridging but not earthing haven't worked either.
The projector was working till the last bulb blew recently and i'd love to get it working without original bulb.

It will be better if I can see the PCB around this connector but my guess is
1. Lamp OK signal
2.Check Lamp signal
3.VCC 3V
4.GND

Probably the pin 1 need to be at 3V (2.7V) connect to pin 3 "but maybe only after is sending the signal on pin 2 ".
So tray to connect pin 1 and 3 but after some seconds from start.

hi electrodacus,
I just got my 2nd hand projector. One problem when I was trying to open the cover. It uses a special screws that I don't have the screw driver against it.
Can you have a look ?

Thanks

It's a security bit. Just get a security bit set from Ebay.

You can find this at any hardware store or this http://www.dealextreme.com/details.dx/sku.6295

Just want to make sure
Is is called T6 screw ? Tks.

hi electrodacus,
I have the InFocus LP335 with service menu attached. How can I by pass the ballast? Should I just connect the VCC +12V and the Return signal in the J2 Socket? What is the +300 VDC ?

Thank you.

Hi electrodacus,

i take long time to take a look i your wonderful job...

I interesting to insert led into my beamer (sanyo Z2, infocus LP130)

first i know that for dlp projector i need to concentrate the light on one point
just before the color wheel and for 3 LCD i need to have a "box of light".

I have buy from dealextreme the 20w led with 800 lumens but i
have found other led with 20w and 1400 lumens...(but it is
not disponible for the moment)

My problem is how you can have a power for 3,6v at 4 or 5 Amp
(to have one or two led at 20w)

i have found that this man use a soul P7 with 900lumens but
i don't understand how they do with a laptop adaptator to
have 3,6volt output...(because there is not laptop power
with a output at 3,6v).


http://cgi.ebay.fr/videoprojecteur-BenQ-MP...3QQcmdZViewItem

Excuse me for my poor english, i'm from france.

If you could help me for this point i would greatly appreciate
because it blocked me to go farther.

Again you have done great and very very interesting job.

best regards,
Vincent.

I sent you a private message please do not touch the J2 connector ab be careful 300V DC can kill you in less than a second and even if the power plug is not connected.

For LED's you do not care to much about the Voltage the most important parameter is max current 2.8A (4x700mA 4led connected in paralleled) for the P7 so you need a power supply than can deliver 2.8A or more and you need to limit the current to 2.8A or less for this LED to limit the current the easiest way is to use a resistor in series with the LED and the value of this resistor need to be calculated the formula will be R = Vpowersupply - Vmaxled / current
I will give you 2 example:
EX1:
Vpowersupply = 12V
Vmaxled = 3.6V
current = 2.8A

then R= 12-3.6/2.8 so R = 3 ohm
but you need a big Resistor because the power loss on the resistor will be Presistor=Vresistor * current
Vresistor = Vpowersupply - Vmaxled so Vresistor= 12-3.6 Vresistor=8.4V
Presistor = 8.4 * 2.8 = 23.52W this is a lot of power you will not find to easy a resistor of 25W or more (you can use more smaller resistor )
EX2:
Vpowersupply = 5V
Vmaxled = 3.6V
current = 2.8A

then R= 5-3.6/2.8 so R = 0.5 ohm
but you need a big Resistor because the power loss on the resistor will be Presistor=Vresistor * current
Vresistor = Vpowersupply - Vmaxled so Vresistor= 5-3.6 Vresistor=1.4V
Presistor = 1.4 * 2.8 = 3.92W this is still a lot of power you will be able to find a 5W resistor or more (you can use more smaller resistor )

I used the same LED in EX1 and EX2 with the same current so also the same light output but in first example the power consumption will be 10W led + 23.5W resistor so a total of 33.5W and in EX2 10W + 3.92W so a total of 13.92W .

These are some example just to understand that for LED the most important parameter is current if you limit this you get also the right voltage on LED.
using Resistor is not the best idea but is the easiest thing to do.
There are some special drivers for LED that use more components like transistors, capacitors and coils and have much better efficiency than using just resistors.
I hope I was not to confusing
If you search on the internet about LED drivers you will find more .

dear electrodacus,

Of course if really sorry to not continue electronics at school long time...

So for my case i have :

A led With 20Volt and 20W (so i suppose 1 Amp)

I have found power supply with 20Volt and 3.25 Amp

so if i use your calculation i not need any resistor with this type
of led and power supply ? so i just have to plug directly the
power supply on the led and all will be okay ?

But for the 3,6V led i need a driver who can transform my voltage
20Volt to a 3,6volt...but i have to found power supply ith small voltage
at the ouput to found easy driver.

I try to research to have 3,6volt from the same power supply with driver.

I post some photos of my result when i received led, optic and power supply.

I maybe take another same led to have more lumens.

Thanks for your help,
regards,
Vincent

So if i'm right understanding :

4 x Seoul SC P7 at 900lumens links in serie
with 3 Volts the easy way for me is to use
a laptop power with 12Volt output and the amp
for one led only (because i add voltage).

4 x Seoul SC P7 at 900lumens links in parallels
with 3,3 Volts the other way for me is to use
a power with 3,3volt and 6amp (i found one
on internet).


This two type is right and i don't need any resistor
because the Vresistor is equal to Zero.

and when i received my 20V 20W (1amp) led i can lug it
directly to the 20V power supply (3,5Amp) ?

I'm right or totally out of the truth

thanks again,
Vincent

I guess you have this LED 20WLink and inside you have 20 x 1W led that are connected 5 in series on 4 rows .
on each LED you get a voltage drop of 3.6 to 4V so multiplied with 5 you get the 18 to 20V for the 20W LED and you will need 1A.
I will suggest a 24V power supply for this LED is not possible to eliminate current limitation (using a resistor or current limitation circuit).
Also the P7 is based on 4 led you can see the 4 LED emitters in the linked photos and this are connected in parallel P7Link
Unfortunately the LED is more difficult to use than a incandescent bulb.
I suggest you to use only one power LED for the projector the 20W that you have will be fine but you will need a big Heatsink or a SSC P7 that will give the same light output but for half the power consumption and heat dissipation.
This is a small tutorial bat are a lot more on the internet Link
The idea is that the LED without current limitation will take all the current that is available and will get damaged from high heat.
I'm really not to good with explanations also my english is not to good.

Of course i understand now the difference between serie and parallels and
with you need to use a ressitor, but you not really answer to my question :

If i received my laptop power supply at 20v with 3,5Amp i could
able to plug it direcly to my 20W led ithout resistor...?

Because i have same Voltage and enought amp
(i take 3,5 amp because i don't want to have heat on power supply)

Your link about led explaination is great and very easy to understand,
i print it a keep it.

You are right about the type of led i take, i take 20W led because of
the 20V need is more easy to find that 3,3V power.

Kinds regards,
Vincent
Note : Your english is very good, better than mine

Hello!
I have 2 projektor and 1 buyed a 3.
The first is vga resouliton and not good for anything...
The second is philips 4445 this black is going to green:S
And I'm buying a infocus lp820 whith a little problem.
1 filter is next to the lcd is burned. But maybe i can repair it.
I want to change the lamp type to led.
1 question.
If the package is here. can you help me at this modding? of corse just in this forum
How can i disable the lamp checker elektronik.
where can i buy cheep power led , what is perfect for this. and what lens you have? can u give me some information ?
I want 2m diagonal picture, and i can do night black in my room.

sry my english but i' m from hungary:D
I hope you can understand what I want , and can you help .
I'm waiting for answere.
And the projektor what u have is perfekt:D GZ!

short answerer NO
The LED doesn't now when to stop is to hungry and will take all 3.5A an will die of high fever. (you need current limitation)



Is OK to have more amps that are needed (even if you have 1A power supply you can not connect the LED directly).



I recommended 24V power supply for 20VLED and 5V power supply for 3,3 to 3.8V LED

Is not possible to use LED's without current limitation (I now this is a bad news).

Yes I will try.

This depends on the projector If you make some photos with the electronics inside I will try to help.

the LED I recommend is SSCP7LED and with this Lens
With this LED is no problem to project 2m diagonal in a dark room.


my english is also not that good last year I moved to Canada from Romania so I now Hungary.

85 $us for the led 3000 Lumens 50 watt
40 $us for the powersupply - you can modify the current with a button
20 $ for Convex And Concave lens wich a short focus range (there is a used lens website somewhere)
+ thermal paste
>>>
http://www.tigerdirect.ca/applications/Sea...6&CatId=798
http://www.edison-opto.com.tw/news_detail.asp?nno=23
<<<
and imagination, priceless

hi electrodacus,
I have connect the Lamp_Enable and Lamp_Lit, it appears running fine with no yellow indicator flashing (which normally when something wrong with the Lamp). The fan and color wheel seems running fine, but when I tried to place in a Camp Cap LED head light against the optical engine, it has no images. I can see a white screen before turning on the PJ, after turned on, it appears to be black with no text and images, it supposes to be blue screen with "Infocus" logo. It seems that the DMD (image engine for DLP PJ) is not driven correctly.

I look up the motherboard and the optical engine again. I discovered there is a light way comes from the optical engine and facing a special small "black" chip in the motherboard. I suspect this is a Photosensitive Diode which to drive the DMD, while my LED CAP head light is not strong enough to drive the Diode. Can you teach me how Can I by pass the Photosensitive Diodes? Or should I Put a 5mm LED facing the diode? Or Can I short the two end of the diode? How does a Photo-sensitive Diodes works when it sense the light ?