Optics

Optics (Greek οπτικη - optike - " Teaching from the visible ," optiko " belonging to the see," opsis " seeing " ) is an area of physics that deals with the propagation of light and its interaction with matter, especially in the context of optical pictures, busy. Optics is therefore also known as the theory of light.

The "technical optics " in the sense of a definition of optics as part of the field of physics no optical, but a technical discipline. In addition, the sum of all optical components of an optical device is colloquially known as optics, without being a science.

Under light is generally understood to refer to the visible part of the electromagnetic spectrum in the range 380 nm and 780 nm ( 790 THz to 385 THz). In physics, the term light is sometimes extended to areas invisible electromagnetic radiation, and includes in common usage, then the infrared light or the ultraviolet light. Many laws and methods of classical optics are also valid outside the range of visible light. This allows for a transfer of knowledge of optics to other spectral regions, such as the X-rays ( see X-ray optics ) and micro and radio waves.

Also beams of charged particles move in electric or magnetic fields, often under the laws of optics ( see electron optics ).

Parts of the optical system

There are two classical approaches to the propagation of light: the wave optics and geometrical optics. Basis of wave optics, the wave nature of light. The laws of geometrical optics are for the case that the dimensions of the optical system are very large compared to the wavelength of light. With small dimensions of the components versus wavelength is called the micro-optics.

An important sub-discipline of optics is quantum optics, which deals with the interactions of light and matter. Particularly the quantized nature of light plays a significant role.

In addition, the non-linear optics ( in which the light, unlike the linear optics affecting the surrounding medium and thus causes additional effects ) and the Fourier optics from theoretical and technical interest. An interdisciplinary sub-region is the atmospheric optics, are examined in the light phenomena in the Earth's atmosphere.

Geometrical optics

In geometrical optics, light is approximated by idealized rays. The path of light, such as through an optical instrument is constructed by tracking the beam path. The Snell's law of refraction describes the refraction of light at interfaces between transparent media with different refractive index ( on surfaces of lenses or prisms). When reflected on mirrors and total reflection by the rule, that the angle of incidence is equal to the angle of reflection. Using this method can be pictures, treat, for example, by lenses or lens systems (microscope, telescope, lens) and the aberrations that occur. An important approximation is the paraxial optics, which can be derived from a linearization of the Snell's law, and important concepts such as focal length and image scale defined.

Wave Optics

As a wave optics the field of optics is called, which is about the wave nature of light. She explains phenomena that can not be explained by geometrical optics, since in them the wave property of light are relevant. For example, an ideal imaging is possible in geometrical optics, in principle, whereas the wave optics shows that the resolution by diffraction effects a fundamental limit is set; this is to consider, among others, in the photolithographic process steps in the manufacture of modern integrated circuits. Important elements of wave optics are:

• Interference between each other overlapping wave fronts.
• Diffraction that shows up when light through small gaps or edges along spreading ( diffraction integral).
• Polarization of light.
• Scattering of light particles in the volume through which the light is incident, is distributed.

Wave optics may describe effects which depend on the wavelength of the light; this is referred to generally by dispersion. ( Example: " Why is the sky blue? " ) Depending on the said mechanism very different models must be used to describe that lead to very different wavelength dependencies.

On the wave optics, crystal optics and magneto-optics build on.

Surface phenomena

The interaction of light with real (ie non- idealized ) surfaces is important for the visual perception of humans, but is still poorly understood. It is significant remission, ie the absorption of a portion of the light and the reflection, transmission, or spread of the remaining spectral component. Reflection and transmission can be described by the refraction of light at the interfaces. Again, a wavelength dependence of most of the mechanisms noted, that the dispersion.

Some surfaces such as human skin, are partially transparent, so that visually there is no reflective surface, but a reflective layer in the uppermost layers of the skin. An abstract description of optical processes on such surfaces is complicated, and one of the reasons that computer-generated images may appear artificial.

The human eye

The eye is the visual sensory organ, it evaluates the stimulus of light of different wavelengths on the photoreceptors to spike trains of ganglion cells of the retina. The physiological optics is concerned with the optics and the structure of the eye. In medicine it is called in the medicine of optometry or optometry question the eye as the measurement of visual range. The act of seeing can be explained only partially by using the optics. The brain plays an important role because it is processing information only to what we call vision. However, this part falls to biology. All transparent parts of the eye work together like a single converging lens and design a highly scaled, inverted, real image.

History of visual aids

With the genesis of the visual aids found on Gotland Visby lenses from the 11th century are connected. Some of these lenses may be able to compete in the picture quality with today's lenses. The origin of the Visby lenses is unclear despite a thorough analysis, the processing of rock crystal, however, was widespread in the 11th century.

The Arab scholar Ibn Al- Haitham (996-1038) wrote of seeing the refraction and the reflection in his book " Treasure of the optics ." Around 1240 the book was translated into Latin. Genial was his idea to support the eye with ground lenses. European monks took up this idea and made ​​later than in the Orient hemispherical plano-convex lenses for visual aids ( Lesesteine ​​).

Technical Optics

The design, the design and manufacturing of optical systems is referred to as technical optics and is in contrast to the physical optics to engineering, since it focuses on the concrete design and manufacture of optical devices and the design of specific beam paths in the foreground. Important representatives of this discipline were, among others Johannes Kepler, Joseph von Fraunhofer and Ernst Abbe. Today's commercial job title is fine optician.

It provides a link between the themes of subdivisions Optical metrology, laser technology and theoretical optics ( including micro-optics, lighting or fiber optics) dar. applies the technical optics, among others, in projection technology, holography and photography, as well as in spectroscopy.

These are the major components, components and devices are listed.

Optical components

• Radiation source
• Lens
• Fresnel zone plate
• Filter
• Planplatten
• Wave plate
• Mirror
• Prism
• Diffraction grating
• Aperture
• Receiver: projection film plane, radiation detector

Optical Components

• Condenser
• Lens
• Fresnel lens
• Double prism
• Integrating sphere
• Different active components, modulators, special light sources and optical detectors

Optical Devices

• Ophthalmometer
• Magnifying glass
• Lesestein
• Glasses
• Telescope
• Binoculars
• Spotting Scope
• Microscope
• Spectroscope
• Laser
• Polarimeter
• Stereoscope
• Laser Link
• Polarizer
• Anomaloscope
• Camera
• Rangefinder ( camera )
• Refractometer
• Lidar
• Tachymeter
• Telescope

Known Opticians

Known opticians were Ernst Abbe, Alhazen, Laurent Cassegrain, John Dollond, Peter Dollond, Benjamin Franklin, Joseph von Fraunhofer, Hans -Joachim Haase, Hans Lipperhey, Zacharias Janssen, Christiaan Huygens, Johannes Kepler, Antoni van Leeuwenhoek, Dmitri Dmitrievich Maksutow, Isaac Newton, Joseph Maximilian Petzval, Hermann Pistor, Carl Pulfrich, Christoph Scheiner, Bernhard Schmidt, Ludwig Seidel and August Sonnenfeld.