| 1 | The wavelength of light and the fundamental forces | [1]- [3] |
| 2 | Light dependent resistors and their uses | [1]- [3] |
| 3 | Photo diode types and their uses | [1]- [3] |
| 4 | Photo transistors and uses | [1]- [3] |
| 5 | Photo thyristors and usage | [1]- [3] |
| 6 | Solar cells and their uses | [1]- [3] |
| 7 | Various structures and uses of LEDs | [1]- [3] |
| 8 | Operating principles and forms of optical connectors | [1]- [3] |
| 9 | 7-segment displays and connections | [1]- [3] |
| 10 | LCD, CRT, Plasma and LED indicators, the working principles of gas | [1]- [3] |
| 11 | LCD, CRT, Plasma and LED indicators, the working principles of gas | [1]- [3] |
| 12 | Laser types and their uses | [1]- [3] |
| 13 | Laser types and their uses | [1]- [3] |
| 14 | Fiber optic cables | [1]- [3] |