What device is used to convert electrical signals into optical signals?

The device that is used to convert electrical signals into optical signals is the Light Emitting Diode (LED) or Laser Diode. These components play a crucial role in fiber optic communication systems. When an electrical signal is applied to an LED or a laser diode, it generates light as a response to the electrical input. This light represents the information carried by the electrical signal.

In fiber optics, the conversion of electrical signals to optical signals is essential because it allows data to be transmitted over long distances with minimal loss and interference. The light produced by the LED or laser diode is coupled into a fiber optic cable, where it propagates as an optical signal. This capability is foundational to the operation of fiber optic communication systems, as the efficiency and speed of data transmission are significantly enhanced through the use of optical signals rather than relying solely on electrical signals.

Understanding the function of LEDs and laser diodes in this context is vital for mastering the principles of fiber optics and data communication technology.