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:? how to use a photodiode to detect candle light??
i'm building a fire fighting like robot...how to get photodiode as the eye for finding candle light?? o anybody has any better suggestion to me....
thank you... :wink:
You'll need more than one diode to detect in which direction your burning candle is perhaps if you arrange them in a pattern you could steer your robot towards the biggest light output from the diodes.
You could get away with a single light sensing diode if you spin it in a horizontal circle and use a computer to interpret the changing light output with reference to a simultaneously rotating anglular position sensor.
Maybe an infrared photodiode might be better to sense fire, there's a lot more heat than visible light output from a candle.
okie....but how does the thing work?? i mean do i need a proccessor to proccess the data collected?? i'm using a pic to be my center proccessing unit so i just need i high o low signal from the source finder to my pic only..
I am also using photodiodes in my project but for a different purpose. I too am unsure how to connect it into my circuit. Firstly, I have read that a photodiode in concept is a current source in shunt with diode. Then I read somewhere else that its actually like a light switch. So I am just a bit confused whether a photodiode requires a power source or it generates current when it detects light.
When a photon, or light, hits the material in the photo diode, excited electrons are released and create current. Putting a resistance in shunt with the diode will create a voltage in the resistor. But it is best to amplify the output of the diode to something usable by the rest of your circuit.