DIY Modular LED-Light

Guod ...
The new "black oslons " ,were mainly developed for "security " applications ...
(Infra-red sensing -imaging ) ...
At ~940 nm ,I can't really see ,their true purpose ,in the fixture ,as an NIR light source ...
(Almost all of their light ,is reflected by almost all higher plants .. )



"
Concealed security systems – such as those installed in banks, on machinery and at border controls – need to be designed so they are unobtrusive. This is a major challenge for infrared illumination in such applications because the 850 nanometer (nm) LEDs that are most often used here appear as weak dots of red light especially in dark environments. The solution is to switch to a wavelength of 940 nm, which the human eye is 130 times less likely to notice. Camera sensors however can easily detect this invisible radiation.
The Oslon black SFH 4725S from Osram Opto Semiconductors is the ideal component for such applications. This compact infrared LED provides 940 nm light with the high optical output of 980 milliwatts from an operating current of 1 amp. Behind this high performance lies the Nanostack technology in which Osram has succeeded in providing two emission centers in one chip, almost doubling the light output. The SFH 4725S achieves a radiant intensity of 450 mW/sr at an emission angle of 90 degrees and therefore provides excellent illumination over the area being monitored. Radiant intensity (measured in milliwatts per steradiant) indicates the light output within a solid angle segment and therefore defines the intensity of the light beam.
The black package ensures that the component is completely concealed behind the camera lens. “The 940 nm SFH 4725S is a further addition to our Oslon black series for the security sector, which already includes 850 nm versions with standard and Nanostack chips,” said Dr. Jörg Heerlein, Head of Product Marketing for industrial infrared components.
In the compact class the Oslon is currently one of the most powerful versions for both visible and infrared illumination. Measuring only 3.85 x 3.85 x 2.29 mm, the infrared Oslon components are among the smallest IREDs with around 1 W optical power, . “Users with experience in constructing visible lighting units can transfer their know-how and their processes directly to the infrared Oslon,” added Dr. Heerlein. The market is also full of lenses that designers can use to shape the beam from the IRED to meet their specific requirements. "



Or it can be the SFH 4715S ,which has a peak emission at ~850 nm ...
Still ,plants reflect ,most of that light ...
 
hello everyone!
Can someone explain to me if it really helps the purple color;
we see that many are using purple color to their panels ..
SDS you don't prefer the usage of purple because it does not do anything or because most white spectums
give better results than the purple;:confused:
just a silly question from a silly person..:bigjoint:
 
picolada, I'm with you here. One of those Purple LED's had a very sexy secondary peak at ~640nm, abundant IR, and a very Royal Blue primary peak (shorter wl than most Whites I've seen). Mix in some 630's, 660's, and maybe your favorite White LED to round out the Blue spectrum a bit and you've got a pretty nice looking unit, imo. I think Purple (or Pink) could take the place of Neutral White, but.. Idk.
 
stardustsailor said:
Guod ...
The new "black oslons " ,were mainly developed for "security " applications ...
(Infra-red sensing -imaging ) ...
At ~940 nm ,I can't really see ,their true purpose ,in the fixture ,as an NIR light source ...
(Almost all of their light ,is reflected by almost all higher plants .. )
Click to expand...

here....

OSLON Black

High efficient LED at low space and high robustness.

http://catalog.osram-os.com/catalog...Oid=000000060000e3aa02920023&act=showBookmark


LA H9GP


  • Luminous Flux: 80 lm at 350 mA up to 180 lm at 1000 mA
  • Feature of the device: small size high-flux LED for slim designs high robustness
  • Color: amber (617 nm)
  • Viewing angle at 50 % I[SUB]V[/SUB]: 90 °

LT H9GP

  • Luminous Flux: 93 lm at 350 mA up to 165 lm at 1000 mA
  • Feature of the device: small size high-flux LED for slim designs high robustness
  • Color: true green (528 nm)
  • Viewing angle at 50 % I[SUB]V[/SUB]: 90 °
  • Optical efficiency (max.): 135 lm/W at 100 mA

and more.
 
guod said:
here....

OSLON Black

High efficient LED at low space and high robustness.

http://catalog.osram-os.com/catalog...Oid=000000060000e3aa02920023&act=showBookmark


LA H9GP


  • Luminous Flux: 80 lm at 350 mA up to 180 lm at 1000 mA
  • Feature of the device: small size high-flux LED for slim designs high robustness
  • Color: amber (617 nm)
  • Viewing angle at 50 % I[SUB]V[/SUB]: 90 °

LT H9GP

  • Luminous Flux: 93 lm at 350 mA up to 165 lm at 1000 mA
  • Feature of the device: small size high-flux LED for slim designs high robustness
  • Color: true green (528 nm)
  • Viewing angle at 50 % I[SUB]V[/SUB]: 90 °
  • Optical efficiency (max.): 135 lm/W at 100 mA

and more.
Click to expand...

Ok ....That explains everything .
Once more ,you've been most helpful ..

@Picolada & @ Bumping Spheda .
Because I really do not want to hi-jack Guod's thread ...
I've already posted ,in the recent past ,some stuff , about pink/purple leds ...
In short : They need to be tested .
 
thank you very much Bumping Spheda..
i am asking this because many people prefer that spectrum..
yes i have read some of your posts (SDS) in the past,but i see you don't trust the purple spectrum so much(yet)..
but many manufacturers prefer to make panels with that purple spectrum and i just wondering..
i'm asking sorry from quod for hi-jacking his thread..
 
^^^ ...
@Psuagro ....
Trust me .....
FUTURE itshelf ...
(I'm sure is gonna make Heliospectra ,look like a "toy " ....
Those plastic fan guards ...
(yeah they do not rust ,and they are lightweight ..They're plain ...it....)
And ,Guod ,I 'm sure he's going to use a better choise of leds (regarding some of them ,only ...
...Lxn ..-like ones ... ;-P )
 
^^^ah I see now/hope it's cheaper than the Helio:P.............Have they already been granted the patents??funny how everyone says patent pending designs and other bs, but these guys actually have them.

"most sophisticated competitor is US based ORBITEC doing work with NASA" .....this is interesting
 
Guod ,there's something I need to say ...
You have been most helpful to me ,as nobody else has before ....
If there's anything ,that I can do for ya ,do not hesitate to pm me ..

Thank you for everything ,once more ...

If it wasn't you , most probably I would not had made my GD-SDS box ....
You shared my dream ,with me ...
That speaks a lot for a man ....:hump::hump::hump:...
 
thanks again, for your help.
have now 4 of this panels in the tent and the are working quiet and cool.
and as you say, there is a lot of air movement from the panels, so i kick the other fans out. and the girls are still dancing.

here are some pics of my mandalas under 120W
.P1090011.JPGP1080855.JPG

yabo
 
ok....

A question regarding GD-SDS box and it's cooling ...


The fans ....fans.jpg...
I've chosen the " H " bin ....
The "middle" way ....


Each fan has a flow at 48V ( 3000 rpm ) at 36.26 CFM ...

A) Since the fans are placed side by side ,their air-flow is multiplied by two ...

So total air -free- flow is 72,52 CFM .

.....

Outlets (exausts ) of box have a size of 40 mm x 160 mm ,~half of the surface covered from heatsink base and fins (profiles) ...
So input for overall size of exaust is ((40x160 )/2 )*2 ...= 40x160 mmm ....
So ....


cfm to ms2b.jpgcfm to ms2.jpg...

~5.35 m/sec airflow at heatsink fins ....
And ......


resfinal.jpg
......


5 m/sec is max ,at this calculator ....


So , there is ~0,110 °C/W .....



Now ...
Leds ....

Each pcb ...

Reds : 4 x 2.35 x 0.7 = 6.58 Watts at 700mA
WW : 8 x 3.4 x 0.7 =19.04 Watts at 700 mA

Through efficiency ..
At average 65% is heat ..( Rough estimation ) ..say for both leds ( reds T3 bin 355-400 mW output ) ( WW lowest bin ...Say 350 mW output ? )


6.58 * 0.65 =3,29 Watts heat from reds ....
19.04 *0.65 =12,376 Watts of heat from WW ...

All ...Ha ..15,666 Wats of heat ....(Hell .... )

3 x 36 leds = 3* 15,666= 46.998 Watts of heat from 36 leds ...At @700mA ..

46.998 * 0.110 = 5,196 °C over ambient temperature ....


Well ...

At 700 mA ,and with the fans working at ~39 Volts ( ~1500 rpm ? ) ....
Heatsink base (finside ) is only about 2,5-3 °C higher than ambient ....

Pcb at outer side ,( thermocouple sensor in contact with led case ),
has a temp difference from ambient ~16-17 °C .....


Does things seem ok ?

Is the " thermal slug enhanced" design,possibly ,the reason for that 2.5 - 2 °C difference from calculations ?
(heatsink is working more efficient than calculated ! Or somewhere I've done a mistake ? )
 
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