Visual Light Sensor

Visual Light Spectrum Sensor Arrangement

  • Current-limit resistor for Red and Blue LED’s: 330 ohms. (Same as other LED’s, short pin goes to ground)

  • Load resistor for TEPT4400 Visual Light Spectrum Sensor: 20k ohm or 43k ohm. (long pin is the ground pin)

  • Either resistor will work for the Light Spectrum Sensor. You can test with both and decide which one gives your specific rig better values. A larger resistance gives a larger voltage output. It is also recommended that you slip a short section of black heat-shrink tubing onto the Light Spectrum Sensor. This will help shield it from output fluctuations due to changes in ambient room lighting.

  • A schematic of the setup is given below.

    • The sensor has green tape on one of it's legs while the LEDs do not. Since they all look very similar you will want to keep them separated.