LED fiberoptic medical lightsource

Hi, this is my first time here. I have an old fiber-optic light source for a portable medical microscope. It uses an Osram xenophot 64634 HLX EFR 15V 150W GZ6.35 base bulb. The bulbs are expensive, fragile, and don't last long. The socket for the base pins burn out and corrode from heat. The source has a heavy transformer in it and so is awkward to move. I was wondering if there are LED components I could assemble to replace this light source and have comparable light. It also needs to be dimmable.
Thanks for any advice.

planebuilder said:

Hi, this is my first time here. I have an old fiber-optic light source for a portable medical microscope. It uses an Osram xenophot 64634 HLX EFR 15V 150W GZ6.35 base bulb. The bulbs are expensive, fragile, and don't last long. The socket for the base pins burn out and corrode from heat. The source has a heavy transformer in it and so is awkward to move. I was wondering if there are LED components I could assemble to replace this light source and have comparable light. It also needs to be dimmable.
Thanks for any advice.

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That bulb will be about 2500-3000 lumens ....essentially an MR16.

Coupling efficiency is likely on the low side, but that gives you a give start for how many lumens to start with. Without knowing the exact optics it's tough to know exactly what to suggest, but I expect you have a fairly simple setup with a lens in front of the bulb to concentrate on the bundle. You want fairly smooth illumination across the bundle, so you do end up throwing away light.

I expect you have about a 6mm bundle as would be typical for those lights.

The Cree CXA1310 has a 6MM diameter lit surface .... butt that up as close as possible (but not touching) the fiber optic, and you could likely get >80% coupling. Unfortunately you would be limited to about 1000 lumens at 93CRI, 3500K or 1200 lumens at 4000K, 80CRI. Going with a higher CCT will give you a better color gamut which can be useful. Depends what you are looking at.

The XML2 can have as high an output, but optically coupling will be more difficult. Luminous devices are not in the CCT you are likely looking for.

Actually now that I think about it, the http://cree.com/~/media/Files/Cree/LED Components and Modules/XLamp/Data and Binning/ds MHDG.pdf

The new MHD-G would be absolutely perfect. It has the right source size, lots of CCT/CRI options. Find an off the shelf board and heat sink, and you could simple drive the LED with a dimmable LED driver, or cheap adjustable current power supply.

Semiman

I suggest you to use this LED from Bridgelux BXRC-56G4000-F-04 this LED is with color temperature 5600K and 90CRI and 3000 lumens output. You can buy this LED from Digi-Key from here BXRC-56G4000-F-04 .

If you are new to the LEDs I will explain this further.
Color temperature of 5600K means that this is white light close to the sunlight and not yellowish like an incandescent bulb.
90CRI - is color rendering index - approximately it shows how much this light is close to the real sunlight. 90 means 90%.
3000 lumens - lumens are amount of light , just unit. And if SemiMan is right the light coming from the old bulb is 2500-3000 lumens. So this mean that this LED should be enough for you.

1. This LED is coming mounted on a aluminum plate with holes so it will be easy to assemble with screws. It even has pins for connector so you can connect it easy.
I'm offering it to you because it's easy to assemble.
2.Don't forget mount the LED on a heatsink. You can use old CPU cooler with fan or i think SUNON had preassembled heatsink with fan. If you need more help write here and I will try to reply.
3. You will need LED driver for 1A current with power over 30 watts. So just buy LED driver with 1A drive current and lets say 50 or more watts.

Some info about this type of LEDS - http://www.bridgelux.com/sites/defa...x Decor Class A Data Sheet Rev A 20150331.pdf
and about this one exactly on page 7 http://www.bridgelux.com/sites/defa...-030E & PSG-040D Combined Selection Guide.pdf

I would ignore Nichirensu's post ... As the suggested LED will not work.

SemiMan said:

I would ignore Nichirensu's post ... As the suggested LED will not work.

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Hello SemiMan could you please explain what is your point and why this LED wouldn't work.
What do you mean? Lumen output? Spectrum spikes? Shape?

NICHIRENSHU said:

Hello SemiMan could you please explain what is your point and why this LED wouldn't work.
What do you mean? Lumen output? Spectrum spikes? Shape?

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How about you explain how you will ever concentrate the light from that large array to a spot the size of the entry of the fiber...... you may want to re-read my post in more detail.

The game here is, "How many photons of good, clean light can we get into a 6mm circle?" We'd like it to be nicely centered, but that's another matter. That translates into "Maximum lux on a 6mm circle."

The peak lux of ANY light source is at the source itself. A bare XP-G2 will get about 50 million lux, if you're touching the dome (1000 lumens on a 5mm circle = 50.9 milion lumens per square meter). There is no optical method to get higher intensity. Similarly, a magnifying glass gives about 5-500x intensification of the sun's light at the Earth's surface... Which is a hundred times lower than the intensity at the Sun's surface.

use some direct purpose led for microscopy ( don't have dooms to made wide beam ) with high output

http://www.luminus.com/products/CBT-90.html ( SBT-70 http://www.luminus.com/products/Luminus_SBT70_Datasheet.pdf )

good or not- good ......some kind of '' fibre coupling optic lenses'' ; point it is to minimize light looses through fibres to made light source almost ''coherent''

http://www.carclo-optics.com/optics-for-leds/fibre-coupling/




( depends on object you are researching ( microscope for the transparent objects (need low power light ) but microscopes for reflected light need max power ( special when researching object like deep holes ) ; have olympus SZX 10 )

Yes but the old bulb is also bigger than 6mm, and I guess that there is reflecting system. So if he can fit the Decor-18 LED to the reflecting and concentrating system it will work. Maybe there will be light loss, but there has been light losses until now. And this LED has pretty nice light properties on paper, and it's easy to use.

So basically my idea is that this LED is easy to use.
And lets say he buy 1 LED lets say 20$ heat sink lets say 20$ power supply lets say 20$. So if he can fit it for 60$ he will get the light source working.

Your idea .... Does not work!

AnAppleSnail explained why ....sorry too busy to give you a crash course in basic optics.

some theory

http://www.sensorica.co/home/education/technical-know-how/optical-fiber-coupling

Hm guys. I know that the array is large(18mm diameter) and part of the light will be out of focus. Yes, I know. But in my opinion it can work even if the losses are big. But what is going through my head is that the light is not emitted at 360deg but instead at 180 even the pattern shows that most of the light is emitted at 120deg with peak at the middle, so in my opinion a big portion of the light can be focused from the 18mm LED to the 6mm fiberoptic.And we don't need perfect point-focused light.
I have seen old projectors with lamp that have really low light usage but they still work, no matter that most of the light is not focused and I believe that this case wouldn't be much different, And if you ask me even funnel from aluminum foil to focus the light will be sufficient, maybe even better.

Well, these are the thoughts going through my head.

Planebuilder --- stick to my suggestions wrt source size and do not do what Nichirenshu is suggesting. Unfortunately he does not know basic optical principles ...