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Best Optics For Throw

Helios

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I know a recoil thrower has the tightest beam but for just regular good throw with a large .75" x .75" emitter array are you better off with a large reflector or an aspheric lens?

Basically im trying to get some throw out of this

hi_power_led_10w_100w.gif


I know large emitters are not good for throw but there has to be a way to make it decent.
 
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Helios

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Well I went with Aspheric because the LED doesnt emit much light to the sides like you find with incandescent bulbs so it seems like a reflector wont be as effective.
 

Helios

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I actually did get that plastic reflector so that I can hopefully set my aspheric lens right on top of it. Should help to make sure all of the light is moving forward at least even if not collaminated.

Hopefully with good heatsinking I wont have problems with the plastic melting haha I could not find any metal alternatives...and its only $2.
 

Lotus_Darkrose

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You could also coat the reflector in something fire retardant. That could help prevent melting possibly. Or flame retardant tape/high temperature tape etc.
 

BShanahan14rulz

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It will look funny unless you make it out of focus a little. I'd move it closer to the array than it should be.

Reflector will show up in final image as a ring around the emitter array. More lumens out the front, but not "front and center"
 

Helios

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It will look funny unless you make it out of focus a little. I'd move it closer to the array than it should be.

Reflector will show up in final image as a ring around the emitter array. More lumens out the front, but not "front and center"

Yes thats my plan. Because at focus it will project the image of the LED array but just before that point the light should blend well and still have a fairly tight beam. :beer: or at least thats my hope.
 

set

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If I was you I would just go with the reflector because in order for you to have a semi useable beam with an aspheric it would need to be compleatly out of focus and even then the beam would be full of artifacts. So you should get a lot more throw only using a reflector and a better looking hotspot(if it is in focus).

Also if you were going to use the aspheric and reflector, not only would you have an even worse beam pattern, but you won't have any spill. I find spill very usefull as it allows you to see close objects not in the hotspot. I find having no spill gives you the effect of tunnel vision.
 

Helios

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If I was you I would just go with the reflector because in order for you to have a semi useable beam with an aspheric it would need to be compleatly out of focus and even then the beam would be full of artifacts. So you should get a lot more throw only using a reflector and a better looking hotspot(if it is in focus).

Also if you were going to use the aspheric and reflector, not only would you have an even worse beam pattern, but you won't have any spill. I find spill very usefull as it allows you to see close objects not in the hotspot. I find having no spill gives you the effect of tunnel vision.

I have a flashlight with an aspheric and when set at the focal point it shines a detailed image of the LED but if you just slightly defocus it it becomes a nice clean spot. I also went with aspheric because most cheap and large reflectors are not very efficient as far as the percentage of light they reflect so I would lose a good amount of lumens or have to fork out more money than I spent on the rest of the project just for a nice large reflector. Finally I chose aspheric because it is more suited for use with an led like this. Reflectors reflect the light coming out the sides of a bulb forward but LEDs like this already project most of the light forward so the majority will never hit the reflector and thus never be collaminated giving it very little throw unless you used a very deep and large reflector but again thats a lot of $$ more than the 66mm aspheric I ordered for $7.

Thank you for the heads up about the artifacts though. If I did not already have experience with that using aspheric lenses that could have been a nasty surprise.
 




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