Warm White Leds ....And scientific research .....
Couple days ago,I was "re-viewing' some scientific researches done ,
about leds lights and photosynthesis and/or plant growth ....
Well ...
It ' s ptretty logical ,the fact that most of them,are done with monochromatic led combinations ..
But ...
What about ,if the 'testing field' or the ' testing situations ' don't allow for monochromatic led arrays to be used ?
Which type of led can be used ?
I'll give you two examples (at least..There's more ,for the possible issue 'explorer' to find ...) ...:
1) ....
CISME:
A self-contained diver portable metabolism and energetics system
(...)
The front end of the flow head forms a small fluidic chamber of 5 cm diameter
when it is placed on a coral. Theupper surface of the flow chamber is sealed by a glass plate.
Behind the plate is an array of light-emitting diodes (LEDs,Luxeon warm white).
The LEDs are controlled by a constant current source that can be pulse width modulated (PWM) to
adjust the photon flux on the coral surface. Rather than fit the O2, pH, and T sensors into this small chamber, the system brings the water to the sensors by means of small-diameter tubing and a pump (Fig.3).
This design minimizes the contained volume around the sample organism, in order to measure small changes in oxygen and pH in the shortest period of time.(...)
http://www.psicorp.com/library/SR-1477.pdf
2) The second example is a rather ...weird tool...
A bio-catalyst of burning coal fumes,that turn the CO2 into ..who knows what can be ..(medicines,Vit B12 ,alcohol,methane gas ,proteins,etc ...),is made with the same illumination .....
The 'tool' ... :
Z160 Multi-Cultivator is designed for small scale cultivation of algae, bacteria or cyanobacteria. It consists of 8 test tubes, each holding up to ca. 85 ml of cultivated suspension. The test tubes are immersed in a thermostated waterbath. Each tube is illuminated by an array of warm white LEDs that can generate incident irradiance, which is independently adjustable up to 1000 µmol(photon)/m2/s. Each test tube can be bubbled with gas. The gas is humidified and supplied to each test tube through a manually adjustable valve manifold.
http://www.qubitbiology.com/algae-and-bacteria/cultivation-monitoring-a-b/z160-multi-cultivator/
So..when actually a photosynthetic illumination source is needed ,but not to study photosynthesis vs light,
but in order to i.e have a biologist/diver scientific self contained & portable metabolism / energetics ..lamp ..
(with some other sensors and systems ...Not a simple lamp ! LOL ! ) ,or
To make 'bio- catalysators ' with algae / phytoplankton/seaweed/microrganism cultures...
Hey !
They use just Warm Whites !
Hmmmm .....
....
Now ...
What do I want ?
To grow or make scientific experiments ,regarding light ,to my plants ?
Very 'contrasting' and totally dfferent types of leds can be used for
actually growing plants with some sort of production in mind ....
The more 'specific / targeted wls ' is a light ,the more 'pronounced' will be any
impacts ..Either positive or negative ....
The more "full " ,'complete' ,'full PAR range " ,the light is regarding it's specrum quality ,
the less 'pronounced' will be any impacts ..Either positive or negative ....
( I.e extremely high irradiations ...)
Oh ..yes ...
And spectrum doesn't affect so much the photosynthesis ...
It has other more 'indirect' ways of affecting a plant .
Photomorphogenesis.Circadian Rythms.Phototropism.
To name few of these 'other ways' ...
So still ,'spectrum ' has a valid importance on a led grow light ...
And a question pops -up again ...
What do you want ?
To grow or experiment ?
It took Hans plenty of tries ,to build a top-efficiency 'monochromatic leds combined' panel .
That works more than fine .
...
Great work.Awesome panels.
But there's plenty of R&D 'behind' the looks of those slim fixtures ...
-Do other mono grow led panels / manufacturers have the same level of R&D ?
-Of the experimentation ?
-Of the 'trimming/refining " ?
Probably few ...
Less than 5-10 ,maybe ...
Still ....
He-hey ...
Even asian ,un-efficient warm white cheapos(combined with few reds ) do the job ...
Now imagine those CXAs or Veros ...
Or Q-D arrays ...
There are more than just a couple of 'ways' growing with leds ...
In fact,they are rather plenty of them...
Quite different in many aspects amongst them ,
but all of them sharing the success of effectiveness and high productivity &
the final product's high / finest quality .
Each grower/farmer / mj scientist has to make the choice that best
satisfies the needs,goals,limitations and allowances of the whole 'operation'...
I 'll leave you ,to your thoughts ...
Cheers..