Photonics MCQs January 8, 2026July 11, 2024 by u930973931_answers 43 min Score: 0 Attempted: 0/43 Subscribe 1. What does “photonics” refer to? (A) Study of electrons (B) Study of protons (C) Study of photons (D) Study of neutrons 2. Which of the following is NOT a property of photons? (A) Wave-particle duality (B) No rest mass (C) Speed of light in vacuum (D) Electric charge 3. In the electromagnetic spectrum, where do photons used in telecommunications typically fall? (A) Radio waves (B) Infrared (C) Ultraviolet (D) X-rays 4. What is the fundamental unit of light in photonics? (A) Lumens (B) Photon (C) Candela (D) Lux 5. Which semiconductor material is commonly used in optoelectronics and photonics? (A) Silicon (B) Copper (C) Aluminum (D) Germanium 6. What is the principle behind a laser diode? (A) Spontaneous emission (B) Stimulated emission (C) Absorption (D) Reflection 7. Which of the following is a typical application of photonic crystals? (A) Optical fibers (B) Solar cells (C) Laser pointers (D) Optical amplifiers 8. What is the function of an optical amplifier in fiber optic communication? (A) Convert optical signals to electrical signals (B) Transmit data through optical fibers (C) Increase the intensity of optical signals (D) Control the wavelength of light 9. Which phenomenon is used in fiber optics to transmit information over long distances? (A) Diffraction (B) Absorption (C) Total internal reflection (D) Interference 10. Which material is commonly used as a dopant in optical fibers to enhance their light-guiding properties? (A) Gold (B) Silver (C) Gallium (D) Germanium 11. What is the primary function of a beam splitter in photonics? (A) Amplify light signals (B) Convert light into electricity (C) Split a beam of light into two or more beams (D) Filter out unwanted wavelengths 12. Which optical phenomenon describes the bending of light waves when they pass from one medium to another? (A) Diffraction (B) Reflection (C) Dispersion (D) Refraction 13. What is the typical operating wavelength range of visible light? (A) 400 nm – 700 nm (B) 100 nm – 400 nm (C) 700 nm – 1000 nm (D) 1000 nm – 2000 nm 14. Which optical component is used to correct spherical aberration in lenses? (A) Polarizer (B) Beam expander (C) Aspherical lens (D) Optical isolator 15. What is the function of a polarizer in photonics? (A) Polarize light waves along a specific axis (B) Filter out unwanted wavelengths (C) Convert light into electricity (D) Change the color of light 16. Which optical phenomenon is used to separate light into its component colors? (A) Diffraction (B) Polarization (C) Interference (D) Dispersion 17. Which type of laser is often used in medical procedures due to its ability to precisely cut tissue? (A) CO2 laser (B) Diode laser (C) Excimer laser (D) Helium-neon laser 18. What is an important characteristic of a photodetector used in photonics? (A) Absorb photons and produce a current (B) Emit light when current flows through it (C) Reflect light at specific wavelengths (D) Increase the intensity of incoming light 19. Which optical phenomenon explains the bright and dark bands observed when light waves interfere with each other? (A) Interference (B) Polarization (C) Dispersion (D) Diffraction 20. What is the purpose of an optical isolator in photonics? (A) Prevent reflected light from entering the source (B) Increase the power of optical signals (C) Separate different wavelengths of light (D) Convert optical signals into electrical signals 21. Which device is used to modulate light signals in fiber optic communication? (A) Optical amplifier (B) Photodiode (C) Laser diode (D) Electro-optic modulator 22. What is the primary function of a mode-locked laser? (A) Amplify light signals (B) Generate ultraviolet light (C) Convert optical signals into electrical signals (D) Produce short pulses of light 23. Which type of laser is commonly used in barcode scanners? (A) Semiconductor laser (B) Dye laser (C) Fiber laser (D) Helium-neon laser 24. Which phenomenon explains the spreading of light waves when they pass through a narrow slit? (A) Dispersion (B) Polarization (C) Diffraction (D) Interference 25. In optical communications, what is the purpose of multiplexing? (A) Amplify light signals (B) Separate different wavelengths of light (C) Encode digital information into light pulses (D) Combine multiple signals into one channel 26. What is an important characteristic of a laser beam compared to ordinary light sources? (A) Incoherent (B) Low intensity (C) Monochromatic (D) Random phase 27. Which phenomenon is responsible for the rainbow-like colors seen in a thin film of oil on water? (A) Diffraction (B) Polarization (C) Interference (D) Dispersion 28. In fiber optics, what is the function of a coupler? (A) Increase the power of optical signals (B) Combine multiple optical signals into one (C) Convert optical signals into electrical signals (D) Control the wavelength of light 29. Which optical component is used to split a beam of light into two or more beams? (A) Lens (B) Beam splitter (C) Polarizer (D) Optical isolator 30. What is the primary function of a wavelength division multiplexer (WDM) in optical communications? (A) Amplify light signals (B) Separate different wavelengths of light (C) Encode digital information into light pulses (D) Combine multiple signals into one channel 31. Which type of laser is commonly used in medical treatments to correct vision? (A) Diode laser (B) Fiber laser (C) CO2 laser (D) Excimer laser 32. What is the primary function of a phase modulator in optical communications? (A) Amplify light signals (B) Modulate the phase of light waves (C) Convert light into electricity (D) Filter out unwanted wavelengths 33. Which phenomenon describes the spreading of light waves when they pass through a small aperture? (A) Diffraction (B) Polarization (C) Dispersion (D) Interference 34. What is the purpose of an optical circulator in photonics? (A) Increase the power of optical signals (B) Prevent reflected light from entering the source (C) Direct light in a specific direction sequentially (D) Separate different wavelengths of light 35. Which optical component is used to control the polarization state of light? (A) Lens (B) Beam splitter (C) Polarizer (D) Optical isolator 36. In optical communications, what does BER stand for? (A) Bandwidth Efficiency Ratio (B) Bit Error Rate (C) Binary Encoding Resolution (D) Beam Expansion Ratio 37. Which optical phenomenon describes the spreading of light waves when they pass through an edge or around an object? (A) Dispersion (B) Polarization (C) Diffraction (D) Interference 38. What is the primary function of an optical modulator in photonics? (A) Amplify light signals (B) Filter out unwanted wavelengths (C) Convert light into electricity (D) Modulate the amplitude, phase, or frequency of light waves 39. Which optical component is used to direct light in a specific direction based on its polarization? (A) Polarizer (B) Lens (C) Beam splitter (D) Optical circulator 40. In photonics, what is the primary function of an optical attenuator? (A) Decrease the intensity of optical signals (B) Increase the power of optical signals (C) Convert light into electricity (D) Filter out unwanted wavelengths 41. Which phenomenon describes the bending of light waves as they pass through a prism? (A) Diffraction (B) Dispersion (C) Polarization (D) Interference 42. What is the function of a mode cleaner in laser optics? (A) Filter out unwanted spatial modes from a laser beam (B) Increase the power of laser beams (C) Convert laser light into electrical signals (D) Modulate the frequency of laser light 43. Which optical component is used to spatially filter laser beams and remove unwanted modes? (A) Lens (B) Polarizer (C) Mode cleaner (D) Beam splitter