Florida and has also been observed in California and Texas. No active treatment for this infection has been reported yet and the HLB infected tree will eventually die. However, early identification and removal of the HLB affected trees will secure the healthy trees in the grove. Accumulation of starch on infected leaves is an early symptom of HLB. Starch can rotate the polarisation plane of light in a certain waveband. A customised vision sensor was developed based on this characteristic to identify the HLB symptom. The vision sensor images were compared with the images captured by a colour camera to demonstrate the improvement achieved in this method. Also, the starch accumulation identification was studied for citrus leaves before and after being ground. The results showed an enhanced HLB identification performance using the developed vision sensor.