Object

An object is a material thing that can be seen and touched.

  • An object is intuitively assumed to exist and to be responsible for a unified experience, consisting of visual and other sensations and perceptions.
  • Every object, material, medium or substance that we can see is made of matter of one kind or another. The key differentiating factor is the elements and molecules they are constructed from.
  • You will have come across the elements that make up the periodic table.
  • A close look at molecules reveals that they are made up of atoms composed of electrons surrounding a nucleus of protons and electrons.
  • Light illuminates objects. In a nutshell, different elements and molecules react to light in different ways because of their atomic structure and the particular way they combine to form mixtures or compounds.
  • In the case of an opaque object, it is the molecules that form its surface that determine what happens when light strikes it. Translucent and transparent objects behave differently because light can travel through them.
  • Another factor that needs to be taken into account when light strikes an object is surface finish. A smooth and polished surface behaves differently from one that is rough, textured or covered in ripples.

Object

An object is a material thing that can be seen and touched.

  • An object is intuitively assumed to exist and to be responsible for a unified experience, consisting of visual and other sensations and perceptions.
  • Every object, material, medium or substance that we can see is made of matter of one kind or another. The key differentiating factor is the elements and molecules they are constructed from.
  • You will have come across the elements that make up the periodic table.
  • A close look at molecules reveals that they are made up of atoms composed of electrons surrounding a nucleus of protons and electrons.
  • Light illuminates objects. In a nutshell, different elements and molecules react to light in different ways because of their atomic structure and the particular way they combine to form mixtures or compounds.
  • In the case of an opaque object, it is the molecules that form its surface that determine what happens when light strikes it. Translucent and transparent objects behave differently because light can travel through them.
  • Another factor that needs to be taken into account when light strikes an object is surface finish. A smooth and polished surface behaves differently from one that is rough, textured or covered in ripples.

Opacity

Opacity refers to the degree to which an object, area or surface obscures objects or space beyond.

  • Different processes can lead to opacity including absorptionreflection, and scattering.
  • An entirely opaque substance transmits no light, and therefore reflects, scatters, or absorbs all of it.
  • When light strikes an interface between two media some light may be reflected, some absorbed, some scattered. The remainder undergoes refraction and is transmitted through the second medium.
  • So, opacity is the measure of impenetrability to electromagnetic radiation, especially visible light by a material.
  • An opaque object is neither transparent (allowing all light to pass through) nor translucent (allowing some light to pass through).
  • Both mirrors and carbon black are opaque.
  • Opacity depends on the wavelengths of the light being considered. For instance, some kinds of glass, while transparent in the visual range, are largely opaque to ultraviolet light.

Optic chiasm

The optic chiasm is the part of the human brain where the optic nerves partially cross. The optic chiasm is located at the bottom of the brain immediately below the hypothalamus.

  • The cross-over of optic nerve fibres at the optic chiasm allows the visual cortex to receive the same hemispheric visual field from both eyes.
  • Superimposing and processing these monocular visual signals allow the visual cortex to generate binocular and stereoscopic vision.
  • For example, the right visual cortex receives the temporal visual field of the left eye, and the nasal visual field of the right eye, which results in the right visual cortex producing a binocular image of the left hemispheric visual field. The net result of optic nerves crossing over at the optic chiasm is for the right cerebral hemisphere to sense and process left hemispheric vision, and for the left cerebral hemisphere to sense and process right hemispheric vision.

https://en.wikipedia.org/wiki/Optic_chiasm

Optic nerve

The optic nerve of the human eye is the cable–like grouping of nerve fibres formed from the axons of ganglion cells that transmit visual information towards the lateral geniculate nucleus.

  • The optic nerve contains around a million fibres that transport continuous stream of data which have been received from rods, cones and the intermediate neuron types, bipolar and amacrine cells.
  • The optic nerve is a parallel communication cable that enables every fibre to represent distinct information about the presence of light in each region of the visual field.

https://en.wikipedia.org/wiki/Optic_nerve

optic radiation

The optic radiation are tracts formed from the axons of neurons located in the lateral geniculate nucleus and lead to areas within the primary visual cortex.

  • There is an optic radiation on each side of the brain. They carry visual information through two divisions called the upper and lower divisions to their corresponding cerebral hemisphere.

https://en.wikipedia.org/wiki/Optic_radiation

optical density

Optical density is a measurement of the degree to which a refractive medium slows the transmission of light.

  • The optical density of a medium is not the same as its physical density.
  • The more optically dense a material is, the slower light travels through the material and so the higher the index of refraction.
  • The less optically dense (rare) a material is, the faster light travels through the material and so the lower the index of refraction.
  • A vacuum has the least density and so the highest speed of light.
  • Optical density accounts for the variation in refractive indices of different media.

https://en.wikipedia.org/wiki/Absorbance

Optical phenomena

Optical phenomena result from the behaviour and properties of light, including its interactions with matter. They include absorption, dispersion, diffraction, polarization, reflection, refraction, scattering and transmission.

  • Optics is the branch of physics which 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 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.
  • 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.
  • Practical applications of ray diagrams are found in relation to a variety of technologies and descriptions of how everyday objects work, including mirrors, lenses, telescopes, microscopes, lasers, and fibre optics.

Optical phenomena

Optical phenomena result from the behaviour and properties of light, including its interactions with matter. They include absorption, dispersion, diffraction, polarization, reflection, refraction, scattering and transmission.

  • Optics is the branch of physics which 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 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.
  • 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.
  • Practical applications of ray diagrams are found in relation to a variety of technologies and descriptions of how everyday objects work, including mirrors, lenses, telescopes, microscopes, lasers, and fibre optics.

Optics

Optics is the science of light and how it interacts with the world.

  • Optics explains how rainbows exist, how light reflects off mirrors, how light refracts through glass or water, and what splits light shining through a prism.
  • In addition to visible light in the standard “spectrum” of red, orange, yellow, green, blue, indigo, and violet, optics also deals with invisible parts of the whole electromagnetic spectrum of which visible light is but a small part.
  • Optics is both a science and an area of engineering. It has been used to make many useful things, including eyeglasses, cameras, telescopes, and microscopes. Many of these things are based on lenses, which focus light and can make images of things that are bigger or smaller than the original.
  • While optics is an old science, new things are still being discovered in it. Scientists have learned how to make light travel through a thin optical fibre made of glass or plastic. Light can go long distances in a fibre. Fibres are used to carry phone calls and the Internet between cities.

Geometrical optics, or ray optics, is a model of optics that describes light propagation in terms of rays. The ray in geometric optics is an abstraction useful for approximating the paths along which light propagates under certain circumstances.

  • The simplifying assumptions of geometrical optics include that light rays:
  • Propagate in straight-line paths as they travel in a homogeneous medium
  • Bend, and in particular circumstances may split in two, at the interface between two dissimilar media
  • Follow curved paths in a medium in which the refractive index changes
  • May be absorbed or reflected.
  • Geometrical optics does not account for certain optical effects such as diffraction and interference. This simplification is useful in practice; it is an excellent approximation when the wavelength is small compared to the size of structures with which the light interacts. The techniques are particularly useful in describing geometrical aspects of imaging, including optical aberrations.

https://simple.wikipedia.org/wiki/Optics

https://en.wikipedia.org/wiki/Geometrical_optics

Oscillation

An oscillation is a periodic motion that repeats itself in a regular cycle. An oscillating movement is always around an equilibrium point or mean value. It is also known as a periodic motion.

https://en.wikipedia.org/wiki/Oscillation

Oscillation

An oscillation is a periodic motion that repeats itself in a regular cycle. An oscillating movement is always around an equilibrium point or mean value. It is also known as a periodic motion.