What is Optics: Definition and 999 Discussions

Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviolet, and infrared light. Because light is an electromagnetic wave, other forms of electromagnetic radiation such as X-rays, microwaves, and radio waves exhibit similar properties.Most optical phenomena can be accounted for by using the classical electromagnetic description of light. Complete electromagnetic descriptions of light are, however, often difficult to apply in practice. Practical optics is usually done using simplified models. The most common of these, geometric optics, treats light as a collection of rays that travel in straight lines and bend when they pass through or reflect from surfaces. Physical optics is a more comprehensive model of light, which includes wave effects such as diffraction and interference that cannot be accounted for in geometric optics. Historically, the ray-based model of light was developed first, followed by the wave model of light. Progress in electromagnetic theory in the 19th century led to the discovery that light waves were in fact electromagnetic radiation.
Some phenomena depend on the fact that light has both wave-like and particle-like properties. Explanation of these effects requires quantum mechanics. When considering light's particle-like properties, the light is modelled as a collection of particles called "photons". Quantum optics deals with the application of quantum mechanics to optical systems.
Optical science is relevant to and studied in many related disciplines including astronomy, various engineering fields, photography, and medicine (particularly ophthalmology and optometry). Practical applications of optics are found in a variety of technologies and everyday objects, including mirrors, lenses, telescopes, microscopes, lasers, and fibre optics.

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  1. S

    Solar Thermal Optics - Concentrated Light

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  2. spareine

    Sketch of the electric field of a laser beam

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  3. C

    A Question about derivatives of complex fields

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  4. Y

    Calculating Incidence Angle for Tilted Plate and Light Source

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  5. S

    What is the Connection Between Physics, Computer Science, and Modern Optics?

    I have a b.s. in physics and computer science from Western Washington University. Love the opportunity to be part of the conversation. Love modern optics!
  6. Q

    Creating a two lens system of tunable focal length

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  7. J

    Optics : How many images can be seen in inclined mirrors?

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  8. J

    Optics: What is the color of the object as seen from under water?

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  9. J

    Optics : White light incident on water drop

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  10. C

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  11. M

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  12. Const@ntine

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  13. esha

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  14. Const@ntine

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  15. S

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  16. shihab-kol

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  17. R

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  18. Vaibhav Sahu

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  19. Z

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  20. T

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  21. C

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  22. M

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  23. M

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  24. Biniamin Piash

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  25. 1

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  26. S

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  27. S

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  28. A

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  29. CCR5

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  30. H

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  31. Marcus95

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  32. asteeves_

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  33. L

    Classical Find the Best Undergraduate Optics Book for Graduating Seniors

    Hey does anyone have an Undergraduate Upper-Division level optics book they like? Maybe one that describes the concepts well? I am a graduating senior, last physics courses I'll take as an undergrad and our assigned book isn't well written. Appreciate any help, thanks!
  34. TLU SPS

    Optics Research: Focus Light to <5mm, Cheap Lens Solutions

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  35. Y

    Conceptual question on polarization

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  36. S

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  37. I

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  38. J

    Optical Tweezers in the Ray Optics Regime

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  39. C

    Programs Optics Program or Physics Program (w/ optics concentration)

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  40. J

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  41. S

    I Does Relativistic Motion Impact Quantum Optical Experiments?

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  42. Antraxius

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  43. B

    Refraction of IR "light" in CCD sensors SiO2 layer

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  44. Ian Baughman

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  45. S

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  46. F

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  47. J

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  48. Samama Fahim

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  49. henry wang

    Other How active is the field of Optics in physics and industry?

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  50. qnach

    Classical Finding the Right Optics Book: Faraday Rotator

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