Multichip LED, Remote Phosphor - Guess who it is.

Mirror ?

You don't mean a glass mirror ,I'm guessing ....

Yea, a glass mirror. I'm guessing you think the glass will kill efficiency?

I could always just build it out of plexiglass and glue reflective mylar onto it (squeegee the wrinkles/bubbles out so it's perfectly smooth).

Any thoughts of your own?

Yes ,glass ,within the mixing chamber will definately kill efficiency ...

Look ...
A remote phosphor mixing chamber ...
(from the few ,that I've tried to comprehend .... )
Has to be kinda of a special "reflector" ...

Reflectivity ,surely has a great impact on overall efficiency ,of a RemPho system ...
The higher the reflectivity of the mixing chamber material & design ,the more the light power the Rempho will output ...

But it has to be of high diffusion ..
So ..You 've to forget about specular reflectivity and start thinking about diffused reflectivity ....

3M has some interesting adhensive tapes /foils .,..
CaCO3 is an interesting reflective/diffusive material ...
~99% diffused reflection ...
~97% total reflection ..

( bright White in color ..Non-toxic .
More 'Bright white' {higher reflectivity } ' than ZnO or TiO2 used today as main "white" pigments ..
-'Brightness' close to that of BaO or PbO -which both are way toxic.. )



Fine Blackboard Chalk powder .
(Not the MgCO3 known as baby powder,climbers chalk,talc,magnesium carbonate,ect ...)

How to apply it (and make it adhere ) ,is tricky ...

Here ,in Hellas is very common -specially on islands- to paint outer walls of houses with CaOH* ..

......Heated limestone rocks / stones : CaCO3 = +heat=> CaO ...And some Water Added => CaOH ...

A white ,thick silky paste ,used along with cement and sand ,as
a building material ( Bonding & building bricks /stones/tiles ,as a thick wall plaster ,ect ) ..
Will dry up & eventually burn skin & clothing ,if not washed away ..
Also metallic pipes or wires ,will corrode (by time ) if inside a (dry )cement mixture ,which contains CaOH ...
CaOH is dilluted with water and used as "paint " ...
Antiseptic,antifungal ....
Ecologic ...
97% reflectivity ..
~99% diffusion ....
Same goes with CaCO3 -which is not that corrosive as CaOH ....

Click to expand...

Also take some ideas from Intematix ...

http://www.intematix.com/uploads/files/intematix_mixing_chamber_design_for_chromalit.pdf

Awesome read, SDS. Thanks.

intematix_mixing_chamber_design_for_chromalit.pdf said:

Most surfaces used for mixing chambers can be either diffuse or specular in nature.

...

Standard white LED light source systems require diffuse optics to properly distribute the light from the
individual LEDs. Typical losses due to the diffuse optics are 8-10% or higher depending on the uniformity
requirement. The alternative system approach as shown in Figure 2 is a blue LED pump which illuminates a
phosphor source (ChromaLit) that is remote from the LED die. The blue LED and remote phosphor
approach provides a low glare system capable of up to 30% higher luminous efficacy.

...

A diffuse or specular surface provides good performance with the Intematix remote phosphor as long as the
reflectance (either total or diffuse) is very high.

...

Reflectivity of mixing chamber = Remote phosphor system improvement
99% = 30%
98% = 22%
97% = 19%
96% = 15%
95% = 11%

Click to expand...

I'm thinking it doesn't matter so long as it's highly relfective? I wonder why all their partners specialize in diffusively reflective materials, although I speculate it's for aesthetic appeal due to their intended fields of use?

Specular reflections can create " bright spots " onto remote phosphor " die-side " surface ...
This can have as a result ,decreased efficiency of Rempho and not good(power) homogeneity of light ...(radiance ) ...

The more diffuse(and) reflective ,the material / design of mixing chamber ,the better operation of rempho ....

Dont forget to ph Kid's water and runoff. Especially after adding lime

So I emailed John at VanQ and I guess everything was shipped out last Saturday. Go figure.

I'm almost glad you said that SDS, I'm still contacting the NA distributor for White97 film asking for sample quantities and hoping that they don't try to take advantage of the opportunity. Larger companies would just send out the film for free at this low of a quantity, and slightly smaller companies than that would merely charge shipping. I'd take either one! But more to the point, I haven't liked any of the reflectors that I've seen, tbh, I'm hoping I can do better.

Thanks for the tip, SnotBoogie. I'll probably get totaled for this, but I don't own anything to measure the ppm/pH. I'm hoping a little goes a long way, I really didn't add that much (a pinch), nor did I even let the salts fully dissolve in the first feeding (they're still at the bottom of the repurposed peroxide bottle finishing the job). Fingers crossed I don't run into problems. This is one of the reasons I've kept Kid this long, he tests the waters.

You can buy papers which are nowhere near as bad as people make out for next to nothing. Just search your favourite online retailer for ph strips. Should cost less than $4 for a pack of like 150 or something dumb.

Theyre only broadly accurate but it's enough to see your ph is 6.5 and not 5.5, for example. I think this is all you need when coupled with a common sense approach (this is what i do). The problem with "just common sense" is you only have to be incorrect about one thing to totally fuck it up.

edit: oh and be careful of leaving undissolved matter in your foliar solution. I'm by no means an expert but i believe that you could burn spots on the leaves if they land on them (especially if you do not do a "foliar flush" with plain water the next day), I have only read this but as i've burnt plants myself by splashing nute solution on the leaves, it sounds pretty credible to me.

easy to get here...
3M Light Enhancement Film (LEF) 3635-1003m lef

http://www.youtube.com/watch?v=MDfhQQYr7LU

Not as reflective as the White97 stuff, but definitely good to fall back on. Thanks guys.

Guess what came in the mail...

I gave myself laser eye surgery by firing this puppy up for a millisecond. I held the RP lens over it about a centimeter away and saw spots for like a minute. The light looked "Neutral" to "Cool" White, but I'd almost say closer to Neutral just not as much Green. I'm going to guess that, as guod anticipated, the lens is overloaded.

So, onto the mixing chamber. I've got some samples of a few different White diffusive films heading my way, a few of which that have adhesive backing, a few of which that don't, and a few of which that are thermoform-able. Right now I'm thinking I should make my own vacuum forming table, but it means I have to make some molds which could be complicated. We'll see how it goes. For the record the films that I am expecting are:
WRF-150 (I wanted the thicker film, but he said it wasn't as reflective which sounded shady to me, but w/e) by FusionOptix (thermoform-able)
WO-F23 (adhesive backed and standard) by WhiteOptics (thermoform-able)
MCPET by Furukawa (only semi-thermoform-able, it will kill reflectivity by ~.5% if kept thicker than .4mm, and it hurts more the thinner it gets)
MCPOLYCA by Furukawa (thermoform-able)

I am most excited about the MCPOLYCA. Its reflective, diffusive and thermal properties look pretty amazing.


AND! Last, but not least, a relatively random and silly idea I formulated while reading up on cutting edge LED technology:
The phosphor layer for high temperature RP applications (read high wattage) is usually on a glass substrate due to its superior thermal resistances when compared to plastic. Also, the temperature of the phosphor layer plays a large role in overall efficiency of the system (a large contributing factor to RP's advantage over conventional White LED's). This got me thinking. So, both the LED and phosphor like to stay cool... Why not heat sink the RP lens? But how would you do this without blocking the light, or creating severe hotspots due to the abhorrent thermal conductivity of glass?
http://www.diamond-materials.com/downloads/cvd_diamond_booklet.pdf
Drop $2k on a diamond lens of course. As far as I can tell it has similar light absorption properties compared to glass when strictly looking at the visible spectrum. Also, it's thermal properties are... well they're fucking insane, look at the graphs. You could heat sink the phosphor to the same cooling device that you're using for the LED's and increase efficiency considerably. We just have to wait for the prices of diamond to go down.

It looks lovely!

I take it things like perspex are out of the question? <----RP nubcake

PF: You got a picture of that heat sink? And what's that about finding a heat sink grid and flying solo? I don't follow you.

SnotBoogie: No, they're not out of the question, you just have to be careful you don't get too close to the melting point of the plastic which should be out of the question since the efficiency of the phosphor and LED at that temp would be pretty severely crippled. I was just saying I can't think of a method to heat sink the lens when using glass or thermoplastic (which isn't to say it's not possible, see PF's comment) so the number of Watts per square inch is limited. And hey, you're calling yourself a nubcake when the comment I made about diamond lenses is probably nublord-ish. Anyone in the know would probably laugh their heads off at the thought.


And a slight update on the equipment. I received the 78mm reflector today, put it on, placed the ChromaLit lens on top (relatively nice fit, btw) and fired it all up. Say whaaa? It looks... Warm White to me. Not as warm as the 50W, but I'll ascribe this to the increased CRI of the Intematix lens. So maybe I'm wrong, the 75mm lens might actually be fine for my application. I still want to vacuum form a piece of MCPOLYCA inside of the reflector, though. Not only will it shrink the reflector dimensions by the thickness of the film (hopefully making the ChromaLit lens a slightly better fit), but it should get the LED a little closer to the lens which is good for efficiency anyway. So, with all this in mind, I'll try to keep everything as reversible as possible in case a problem arises or my own curiosity gets the better of me I'll be able to remove the reflector and retrofit a larger one onto the LED (one that accepts the CL-827-R100-XT, 100mm RP lens).

I watered Little Chiesel and Kid yesterday. Little Chiesel looked pretty angry about it at first, but today she's bounced back with obvious growth to her second tier. Kid... well Idk. I've never grown a tomato before, but he looks tired, almost like I've been overwatering him, and yet some of his older leaves are crispy and dried out. I'm wondering if it was the diatomaceous earth that got on his leaves. There were like tiny little fruit flies after I used some Miracle Grow potting soil when I transplanted him and I freaked out at the sight bugs. Sprinkled diatomaceous earth all over his dirt (which solved the problem, no more bugs) but the stuff I got on him seems to have hurt him which doesn't sound normal after researching a little bit. Anyway, hopefully he turns around, or I just don't know what I'm talking about and he's happy as a lark. Who knows.

While it's not a mechanical bond, silicone adhesive has pretty good heat transfer (certainly better than perspex, lol) and would stick.

For thermoforming think ( hot ) air pressure ,oven ,(preheated ) aluminium molds,etc ...

[video=youtube;yhajk_IDTUo]https://www.youtube.com/watch?v=yhajk_IDTUo[/video]

Coollll.....
Didn't know about it ...
Super cool .....
Looks way easy to do .....

OH ....You gave me plenty of Ideas right now !!!


Thermoforming thin Polycarbonate foil over mcpcb with leds ....
Hmm...