Using a hototransistor to follow a light source

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For a mechanical arm project designed to follow a light source, selecting the right phototransistor is crucial. An IR phototransistor can effectively detect light from standard incandescent bulbs, but high sensitivity and fast response time are essential for accurate tracking. It's recommended to choose a phototransistor with a narrow spectral response that matches the light source's wavelength to minimize interference from ambient light. Additionally, the size and placement of the phototransistor should be optimized for the arm's functionality. Overall, careful selection based on these factors will enhance the project's effectiveness.
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I'm working in a project of an mechanical arm that will follow a light source, like a light bulb.
So i'll need a phototransitor to make it work. Which one is the best for this kind of project?
 
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Here is a good way to find parts by parameter search:

http://search.digikey.com/us/en/cat/sensors-transducers/optical-photo-detectors-phototransistors/1967049?k=phototransistor
 
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can you use a phototransistor? usually their supposed to be matched to an ir diode of the same wavelength, that's why when you turn the light on in a room your tv dosen't turn on(that and encoded modulation), maybe a photoresistor would work better.
 


nevere said:
can you use a phototransistor? usually their supposed to be matched to an ir diode of the same wavelength, that's why when you turn the light on in a room your tv dosen't turn on(that and encoded modulation), maybe a photoresistor would work better.

An IR phototransistor will see plenty of activity from a standard incandescent.
 


I would recommend using a phototransistor with high sensitivity and fast response time for this project. This will allow the mechanical arm to accurately and quickly track the light source. Additionally, you may want to consider using a phototransistor with a narrow spectral response that is matched to the wavelength of the light source you are using. This will ensure that the phototransistor is specifically detecting the light from the bulb and not other ambient light sources. It is also important to consider the size and placement of the phototransistor in relation to the mechanical arm to ensure optimal functionality. Overall, careful consideration of the specific requirements and specifications of the project will help determine the best phototransistor for the job.
 
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