Light-emitting diode - Wikipedia
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Infrared - Wikipedia
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Light-emitting diode - Wikipedia
Light-emitting diode - Wikipedia
Infrared - Wikipedia
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Infrared - Wikipedia
IR Transmitter and Receiver Kit - Geeetech Wiki
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Light-emitting diode - Wikipedia
Vishay Infrared LED (IR Emitter) 5mm for Wii Whiteboard Pen IR USA: Amazon.com: Industrial & Scientific
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Infrared - Wikipedia
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Amazon.com: Gesture Recognition Sensor PAJ7620U2, Built-in Infrared LED and Optical Lens, Can Directly Recognize 9 Basic Gestures, Support I2C Interface, Compatible for Arduino/Raspberry Pi / STM32. : Industrial & Scientific
Grove - Infrared Emitter - Seeed Wiki
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Activity: LED as light sensor - ADALM2000 [Analog Devices Wiki]
Light-emitting diode - Wikipedia
Light-emitting diode - Wikipedia
Light-emitting diode - Wikipedia
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