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C&G LED FAQ - Q15-Q19

Article Index
C&G LED FAQ
Q4-Q9
Q10-Q14
Q15-Q19
Q20-Q28
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Q15. Are LED diodes inherently directional?


LED diodes are not inherently directional.  One way to boost light intensity is to focus the beam more tightly.  This is accomplished not with the LED chip itself, but a lens which directs light.  MR and PAR series LEDs have a beam angle of 15 to 60 degrees.  This does not change the light output, only the direction of the light.

 


Q16. Why are LEDs different colors?


The color of an LED is a function of the material used to make the junction. There are two main flavors used in visible light LED junctions:

  • Indium gallium nitride (InGaN): used to make up the blue, white, true green, and UV types
  • Aluminum gallium indium phosphide (AlGaInP or AlInGaP): used to make the red, yellow, and orange types

 


Q17. Do LEDs have a wire filament?


No, LEDs operate using entirely different components. LEDs are diodes - they only allow power to move in one direction. The anode (+) is where the current comes in and the cathode (-) is where the current goes out, much like the positive and negative terminals of a battery. Incandescent bulbs project light in every direction (omni directional) as opposed to LED lights which project light in specified directions (such as 20, 50 and 120 degrees) due to their package design and layout.

 


Q18. What is an LED?


L.E.D. is the common abbreviation for a light-emitting-diode.

LEDs are based on inorganic (non-carbon based) materials. An LED is a semi-conducting device that produces light when an electrical current flows through it.

A diode is a semiconductor that permits current flow in one direction.  Semiconductor diodes are a junction of two materials, one with a positive and the other with a negative charge.  When this PN junction is applied with a forward voltage, electrons and holes are brought together releasing light energy.  Hence: Light Emitting Diode.

 


Q19. What’s SSL technology?


Solid-state lighting (SSL) technology uses semi-conducting materials to convert electricity into light. SSL is an umbrella term encompassing both light-emitting diodes (LEDs) and organic light emitting diodes (OLEDs).