This document discusses optoelectric devices that interact with light, including light detection devices like photo cells and photodiodes, light conversion devices like solar cells, and light emitting devices like LEDs. It provides information on the frequency range of visible light and describes the construction and operation of these different optoelectric components.

1. Optoelectric Devices

2.  Light
• Electromagnetic radiation visible to human eye
• Frequency range
 300 to 300,000,000 gigahertz
• Visible region
 400,000 to 750,000 gigahertz

3. Figure 26-1. Photo cell.

4. Figure 26-3. Construction of a solar cell.

5. Figure 26-5. PN junction photodiode.

6. Figure 26-6. PIN junction photodiode.

7. Figure 26-7. Photodiode package.

8. Figure 26-9. Voltage divider using a photodiode.

9. Figure 26-12. Darkness-on DC switch.

10. Figure 26-13. LED construction.

11. Figure 26-14. Common LED packages.

12. Figure 26-19. Commercial optical coupler.

13.  Semiconductor devices that interact with
light
• Light-detection devices
• Light-conversion devices
• Light-emitting devices
 Light is electromagnetic radiation that is
visible to the human eye

14.  Light-sensitive devices include photo
cells, solar cells, photodiodes, and
phototransistors
 Light-emitting devices include the LED
(light-emitting diode)
 An optical coupler combines a light-
sensitive device with a light-emitting
device