Description:
The Light sensor (1143) can measure ambient light up to 70 kilolux (roughly equivalent to the brightness of direct sunlight). Each sensor has been individually calibrated, and a label has been applied to the back of the board with a calibration value which can be used in your calculations to increase measurement accuracy. The sensor's output is logarithmic, so it will be more accurate at low light levels. When no calibration label is available, you can use the generic values ( m = 0.02385 and b = -0.56905 ).

Some light sensors report drastically different values depending on the type of light being detected. The 1143 light sensor, however, only differs by a factor of 1.2 when measuring fluorescent light versus incandescent.

If you want greater resolution with a smaller measurement range, take a look at the 1142 – Light Sensor 1000 lux. This sensor connects to any device with an Analog Input.

Specifications:

• Input Voltage: between 4V and 5.5V
• Power use Adapter board: 0.5 mA
• Sensor Type: Light
• Sensor Output Type: Non-Ratiometric (output not influenced with input voltage)
• Response Time Max: 0.5 ms
• Peak Sensitivity Wavelength: 560 nm
• Light Level Min: 3 lx
• Light Level Max (5V): 70 klx
• Light Current Ratio: 1.2

Resources:
More information to be found in the User Guide