infrared-emitters-and-detectors as array

KeithWalker

Joined Jul 10, 2017
671
I was not able to find a datasheet for the SEN-00241 IR detector that you plan on using so you will need to do a bit of experimenting with the resistor value and the supply viltage to get the best results. The simplest solution would be to connect all of the diodes in series, anode to cathode with a single resistor as shown in the drawing below,
When all of the diodes are illuminated, the voltage out to the comparator will be low. If illumination is blocked to any one of the diodes, the output will go high.
Regards,
Keith
Drawing1.jpg
 
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Bernard

Joined Aug 7, 2008
5,396
'Once used 6 SM NPN photo transistors close spaced with 1 meg ohm collector load feeding into 8 input NOR to detect water drops.
What is Tx to Rx spacing ?
What is Tx beam angle ?
 

KeithWalker

Joined Jul 10, 2017
671
@KeithWalker
Hi,
Data-sheets for Emitter & Detector.
E
Thanks, Eric. Unfortunately the information is very sparse. It shows current / illumination but only at a fixed 5V cathode voltage. Grcshekar will have to do a bit of experimentation to find the cathode current of a detector when it is being illuminated in his grid and the minimum cathode to anode voltage required to achieve it. This can be done by connecting one diode in series with a 100 Kohm potentiometer and milliameter across a 10 or 12 volt supply. When the series resistance is at a minimum, the illuminated current will be indicated by the meter. The resistance is increased until the current starts to drop rapidly. At that point, the minimum required voltage (Vca) can be measured across the diode. Once that is known, the minimum supply voltage can be calculated by multiplying the Vca by the number of diodes.
Note: The supply voltage must not exceed 30 volts because that is the specified Vca MAX for this diode.
 

Bernard

Joined Aug 7, 2008
5,396
With a beam spread of +- 10 deg. IR is spread over about 8" dia. spot. We had good results on a
Corn Hole Game with Rx & Tx similar to yours using a small lens, about 1.5 in dia. 2'' FL. on Tx
& a conical reflector on Rx. Range about 5 Ft. Easy to adjust spot. Out of time.
 
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