According to the manufacturer, the light source we had used in one of our prototypes has a beam spread of 115 degrees.

http://www.cree.com/led-components/media/documents/ds-CXA3070.pdf

Although we ran the LED array at 1.4 A constant current, we are able to safely double the current to 2.8 A by keeping the case temperature under 25 degrees Celsius with our heat sink that has a large plate transfer area coupled with water cooling.

The doubling of the current doubles the amount of light from the same device, and cuts the number of lights a farmer needs in half.

With the 115 degree light spread, we are able to space our microgreens pans vertically every 7.5″ with nutrient film hydroponics, 8.5″ with coconut weave mat, and 9.5″ with Speedling floating trays.