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1.5.1 Light intensity (in candela [cd])
This is the luminous flux emitted or reflected by solid angle given in lumen/steradian or candela
Steradian is a solid angle subtended at the centre of a sphere by a portion of the surface of the sphere whose area equals the square of the sphere¡¯s radius.

1.5.2 Lighting ([lux])
This is the luminous flux that arrives on an area [lm]/ area unit [©O]
¡úfor an office space, the generally recommended lighting is 500 to 700 Lux at 0.8m height
¡úfor a warehouse, 300 Lux at 1.50m
¡úfor a commercial space, the lighting can be up to 2000 Lux at 1.50m

2.3.1 The mineral LED
The LEDs is in the form of a component to be mounted on the surface (SMD) or a component to be inserted.

Figure 8: Diagram of the LED to be mounted on the surface (Source LUMIILEDS)
Figure 9: Diagram of the LED to be inserted (Source LUMILEDS)

The diode chip is connected to the electrodes, surrounded by a reflector and encapsulated in an epoxy or silicon (for high power diodes) resin.
The epoxy may be colored in the same color as the LED to simplify recognizing it. The diode to be mounted on the surface may be capped by a lens based on the desired application; in the diode to be inserted, the epoxy acts as the lens.

Multiple colors
There also exits multi-color diodes, several semi-conductors that generate different colors under the same encapsulation.
LED size
An LED generally has a diameter of 3 to 10mm.
?¡ú For components to be inserted, the cathode is shorter than the anode and the epoxy forms a plate to the right of the anode to enable it to be identified on a mounted component.
?¡úFor the surface components, the manufacturers have their own marking conventions to be considered on a case by case basis.