Hi all,
am doin a small project color sensor using PIC 16F877a. I used LDR but its not sensing the different colors that are reflected from 3 leds RED BLUE GREEN. So I changed to phototransistor. Now i need a circuit for the same. Because all my works are in vain. I am givin the circuit that i used with LDR.
HI... U CAN USE A IC FOR COLOR SENSING i.e Agilent HDJD-S722-QR999 Color Sensor that sense color and give u a particular voltage than use adc to convert analog to digital and then connect to microcontroller
if ic is costly then use three led for three different color for example u want to detect red color simply use red led at place of ldr
as red led pass more current on red light fall on it........use same theory for all