We built a device to help communicate using simple lasers and LDR's which is not dependent on WiFi, Bluetooth or other radio technologies. We modulate a laser using morse code, which is interpreted on the receiving side using a LDR. Both sides have identical hardware - Arduino Nano for the microcontroller, a red laser, a LDR, and a mosfet module to modulate the lasers. Text is input via a serial monitor on the Arduino IDE, and on the receiving side it gets printed on the serial monitor as well. We built a simple tripod using 3d printed parts and PVC pipes to hold all the parts. For future iteration, we plan to add an I2C OLED display, some buttons and a 3d printable morse key so that the device can be used independently without attaching a laptop. 

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