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Thread: Down-firing LED light bulbs?

  1. #1
    Flashaholic kingofwylietx's Avatar
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    Default Down-firing LED light bulbs?

    I may be looking for something that does not exist. I have searched, to no avail....so I am going to ask you guys/gals.

    Does anyone know of an LED bulb that does not light upwards? Imagine holding a standard A19 bulb by the base. Most/all LED bulbs aim the light upwards. I want one with the heatsink on top, so that it will direct light down towards the base. My application is a ceiling fan where the bulbs are essentially standing up, behind glas covers. While I do get light on the ground, I also get a strong reflection from the blades passing over the bulbs. I find it annoying.

    They do make incandescent bulbs that have a silver/reflective coating on the top of the bulb that performs exactly as I want. However, I want an LED bulb.

    Any help would be appreciated. So, if you know of any bulbs that will work, or have another idea (short of replacing the fan)....feel free to offer your thoughts.

    Thank you in advance.

  2. #2
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    Default Re: Down-firing LED light bulbs?

    Why not go with an MR style LED bulb with the E26/27 base that you need. Should give you the directionality that you are looking for.

  3. #3

    Default Re: Down-firing LED light bulbs?

    That would be no different from what he has now. What he is looking for is a bulb that is positioned upright (pointing to the ceiling), but shines light downward. I don't think such a product currently exists.

    kingofwylietx, if you want to try something, get a cheap lamp that you don't mind hacking apart. Pop the diffusing dome off, and see if you can fabricate a simple cone out of something moderately reflective (white cardboard is surprisingly good for this), and mount it over the LED(s) with the point closest to the LED(s). That should direct a good amount of light downwards. Mounting the cone might be a little tricky though.

  4. #4

    Default Re: Down-firing LED light bulbs?

    Doesn't he need an omnidirectional bulb like the philips alienhead LED bulb?

  5. #5
    Flashaholic* VegasF6's Avatar
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    Default Re: Down-firing LED light bulbs?

    Replace the cruddy ceiling fan with one whose light fixture is pointing down
    I imagine that it is one of the ones with the curved arms ala candelabra style? Certainly the use of more leds in your house is more important than style?

  6. #6
    Flashaholic kingofwylietx's Avatar
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    Default Re: Down-firing LED light bulbs?

    Right now, I have the Philips yellow and silver LED bulbs installed in there. I like the idea of mounting a reflector on top. I considered it already, but became concerned with heat build-up if I reduce air circulation too much. I also thought of using a mirror or even polishing a high-nickel metal plate that could maybe be mounted above the bulb....but I kept coming back to the heat issue.

    I don't want to change the ceiling fan because we completely replaced all our fixtures in the home to what we have now. Therefore, if I change the fan, it won't match all the other fixtures.

    My thoughts were that changing the bulbs would be easiest if they are available. This is in our great/living room, so the light is on anytime we are home. Since it gets more use than any other light in the house, I really want to stick with LED.

    I think Evilc66 is probably right about me needing to create some ingenious reflector. Maybe I can make something out of sheet metal (304SS is pretty shiny when it's polished).

    Any other ideas?

  7. #7

    Default Re: Down-firing LED light bulbs?

    Maybe the EcoSmart 8.5W(450 lumen) Omni-Directional from HD?



    I have one in a standard table lamp and I'd say it throws about 75% of it's light out the side and downwards. It's not the most attractive bulb, but it works as advertised -- in a lamp with a shade, anyway. You'd still have some light bouncing off the fan blades, but not nearly as much.

    They make these in 3000K and 5000K and also make a 13W/800 lumen version in both color temps.
    Last edited by bandits1; 08-21-2012 at 09:21 PM.

  8. #8
    Flashaholic* yuandrew's Avatar
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    Default Re: Down-firing LED light bulbs?

    I would suggest that EcoSmart as well. It works similar to an indirect light where inside, the leds shine upward onto a cone which redirects the light sideways and downward.

    Solidworks Diagram:
    https://forum.solidworks.com/servlet...+BULB+RAYS.JPG

  9. #9
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    Default Re: Down-firing LED light bulbs?

    Can the OP post a picture of the ceiling fan in question, might help?

  10. #10
    Flashaholic* LEDninja's Avatar
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    Default Re: Down-firing LED light bulbs?

    Lighting Science / Ecosmart:


    Lighting Science with a CD-R on top label side down (no label):


    Philips Alien Head (I assume that is what the OP calls his silver and yellow):


    Philips Alien Head with a CD-R on top label side down (no label):


    Camera in AUTO no idea if it affected exposure.

    To my eyes the Lighting Science / Ecosmart bulb shone more light downwards but not significantly more.

    The reflector idea works as shown by just placing a CD on top of the bulbs.

  11. #11
    Flashaholic kingofwylietx's Avatar
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    Default Re: Down-firing LED light bulbs?

    Those are the bulbs I have in there now, the Philips alien head bulbs. I wonder how long a cd would last, if left sitting on top of the bulb? I'm fairly sure that you were only using it as an example, but it may be an easy solution. They are light, cheap, readily available, fairly reflective, and easily replaced.

    @Jason, I can post a pic of the offending ceiling fan. I am out of town on business, so it will be Friday before I can do it.

  12. #12

    Default Re: Down-firing LED light bulbs?

    Idea: Pop the phosphor lenses off the the philips bulb and cut off the top and replace with while cardboard or your shiny tin or whatever.

    edit:
    better idea: just paint the top portion of the philips bulb with some silver or white opaque paint, or even better just stick on some of that aluminium duct tape.
    Last edited by beley; 08-22-2012 at 11:15 PM. Reason: better idea

  13. #13
    Flashaholic* LEDninja's Avatar
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    Default Re: Down-firing LED light bulbs?

    I am only using the CD as an example. For an actual installation I would look at something less flammable than a piece of plastic of unknown flame resistance material. Maybe cut out a circle from an aluminum bake pan or a pie plate.

    The Philips bulb uses the 3 grooves between the yellow covers and the circle on top as the main LED heat dissipators. Don't block airflow through the grooves. An aluminum plate on top can actually increase the surface area of the heatsink. You will have to find glue with good thermal conductance.

  14. #14
    Flashaholic* AnAppleSnail's Avatar
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    Default Re: Down-firing LED light bulbs?

    Make a pretty cone that is silvered or high-reflectance white on the outside. Place this atop any LED light.
    My biggest light-hog is my camera.

  15. #15

    Default Re: Down-firing LED light bulbs?

    Does anyone know of an LED bulb that does not light upwards?

    If you can't find a satisfactory bulb, how hard would it be to change the sockets so they aim the other way?

    Any chance of a picture of the fixture?
    Last edited by Ken_McE; 09-03-2012 at 05:22 PM.

  16. #16
    Flashaholic kingofwylietx's Avatar
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    Default Re: Down-firing LED light bulbs?

    Here is a picture of the fan. You can see that the bulbs are mounted vertically. The glass is open on top, so the brightest light is going upward. It hits the fan blades and that does have a effect below. I am concerned about blocking too much of the top, as it will impede air flow to the LED bulbs.


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