LDR (light dependend resistor)

Light dependend resistor is an electronic component capable of detecting lighimagen ldr


What is resistance?

The resistance measures the oposition of an electric current throught a conductor. The units are Ohms (Ω)

Electrical resistance, the measure of the degree to which a conductor opposes an electric current through that conductor (WIKIPEDIA DEFINITION).

What is ilumination?

Ilumination is the degree or intensity of light. The units to measure light are lux.


Illuminance Surfaces illuminated by:
0.0001 lux Moonless, overcast night sky (starlight)
0.002 lux Moonless clear night sky with airglow
0.27–1.0 lux Full moon on a clear night
50 lux Family living room lights(Australia 1998)
100 lux Very dark overcast day
320–500 lux Office lighting
400 lux Sunrise or sunset on a clear day.
1000 lux Overcast day; typical TV studio lighting
1000025000 lux Full daylight (not direct sun)
32000100000 lux Direct sunlight

The numbers are not distributed linearly. It means that a number 0.0001 lux compared to 100000 lux are difficult to represent.

We need to represent using scientific numbers:

10^-4 = 0,0001

10^2 = 100

10^5 = 100000