A scintillator ( )  is a material that exhibits scintillation, the property of luminescence, when excited by ionizing radiation. Luminescent materials, when struck by an incoming particle, absorb its energy and scintillate (i.e. re-emit the absorbed energy in the form of light). Sometimes, the excited state is metastable, so the relaxation back down from the excited state to lower states is delayed (necessitating anywhere from a few nanoseconds to hours depending on the material). The process then corresponds to one of two phenomena: delayed fluorescence or phosphorescence. The correspondence depends on the type of transition and hence the wavelength of the emitted optical photon.

Principle of operation
A scintillation detector or scintillation counter is obtained when a scintillator is coupled to an electronic light sensor such as a photomultiplier tube (PMT), photodiode, or silicon photomultiplier. PMTs absorb the light emitted by the scintillator and re-emit it in the form of electrons via the photoelectric effect. The subsequent multiplication of those electrons (sometimes called photo-electrons) results in an electrical pulse which can then be analyzed and yield meaningful information about the particle that originally struck the scintillator. Vacuum photodiodes are similar but do not amplify the signal while silicon photodiodes, on the other hand, detect incoming photons by the excitation of charge carriers directly in the silicon. Silicon photomultipliers consist of an array of photodiodes which are reverse-biased with sufficient voltage to operate in avalanche mode, enabling each pixel of the array to be sensitive to single photons.

History
The first device which used a scintillator was built in 1903 by Sir William Crookes and used a ZnS screen. The scintillations produced by the screen were visible to the naked eye if viewed by a microscope in a darkened room; the device was known as a spinthariscope. The technique led to a number of important discoveries but was obviously tedious. Scintillators gained additional attention in 1944, when Curran and Baker replaced the naked eye measurement with the newly developed PMT. This was the birth of the modern scintillation detector.

Applications for scintillators

Scintillators are used by the American government as Homeland Security radiation detectors. Scintillators can also be used in particle detectors, new energy resource exploration, X-ray security, nuclear cameras, computed tomography and gas exploration. Other applications of scintillators include CT scanners and gamma cameras in medical diagnostics, and screens in older style CRT computer monitors and television sets. Scintillators have also been proposed as part of theoretical models for the harnessing of gamma-ray energy through the photovoltaic effect, for example in a nuclear battery.

The use of a scintillator in conjunction with a photomultiplier tube finds wide use in hand-held survey meters used for detecting and measuring radioactive contamination and monitoring nuclear material. Scintillators generate light in fluorescent tubes, to convert the ultra-violet of the discharge into visible light. Scintillation detectors are also used in the petroleum industry as detectors for Gamma Ray logs.

Properties of scintillators

There are many desired properties of scintillators, such as high density, fast operation speed, low cost, radiation hardness, production capability, and durability of operational parameters.
High density reduces the material size of showers for high-energy γ-quanta and electrons. The range of Compton scattered photons for lower energy γ-rays is also decreased via high density materials. This results in high segmentation of the detector and leads to better spatial resolution.  Usually high density materials have heavy ions in the lattice (e.g., lead, cadmium), significantly increasing the contribution of  photoelectric effect (~Z4). The increased photo-fraction is important for some applications such as positron emission tomography.  High stopping power for electromagnetic component of the ionizing radiation needs greater photo-fraction; this allows for a compact detector.
High operating speed is needed for good resolution of spectra.  Precision of time measurement with a scintillation detector is proportional to . Short decay times are important for the measurement of time intervals and for the operation in fast coincidence circuits.  High density and fast response time can allow detection of rare events in particle physics.
Particle energy deposited in the material of a scintillator is proportional to the scintillator's response.  Charged particles, γ-quanta and ions have different slopes when their response is measured.  Thus, scintillators could be used to identify various types of γ-quanta and particles in fluxes of mixed radiation.
Another consideration of scintillators is the cost of producing them.  Most crystal scintillators require high-purity chemicals and sometimes rare-earth metals that are fairly expensive.  Not only are the materials an expenditure, but many crystals require expensive furnaces and almost six months of growth and analyzing time.  Currently, other scintillators are being researched for reduced production cost.

Several other properties are also desirable in a good detector scintillator: a low gamma output (i.e., a high efficiency for converting the energy of incident radiation into scintillation photons), transparency to its own scintillation light (for good light collection), efficient detection of the radiation being studied, a high stopping power, good linearity over a wide range of energy, a short rise time for fast timing applications (e.g., coincidence measurements), a short decay time to reduce detector dead-time and accommodate high event rates, emission in a spectral range matching the spectral sensitivity of existing PMTs (although wavelength shifters can sometimes be used), an index of refraction near that of glass (≈1.5) to allow optimum coupling to the PMT window. Ruggedness and good behavior under high temperature may be desirable where resistance to vibration and high temperature is necessary (e.g., oil exploration). The practical choice of a scintillator material is usually a compromise among those properties to best fit a given application.

Among the properties listed above, the light output is the most important, as it affects both the efficiency and the resolution of the detector (the efficiency is the ratio of detected particles to the total number of particles impinging upon the detector; the energy resolution is the ratio of the full width at half maximum of a given energy peak to the peak position, usually expressed in %). The light output is a strong function of the type of incident particle or photon and of its energy, which therefore strongly influences the type of scintillation material to be used for a particular application. The presence of quenching effects results in reduced light output (i.e., reduced scintillation efficiency). Quenching refers to all radiationless deexcitation processes in which the excitation is degraded mainly to heat. The overall signal production efficiency of the detector, however, also depends on the quantum efficiency of the PMT (typically ~30% at peak), and on the efficiency of light transmission and collection (which depends on the type of reflector material covering the scintillator and light guides, the length/shape of the light guides, any light absorption, etc.). The light output is often quantified as a number of scintillation photons produced per keV of deposited energy. Typical numbers are (when the incident particle is an electron): ≈40 photons/keV for , ~10 photons/keV for plastic scintillators, and ~8 photons/keV for bismuth germanate ().

Scintillation detectors are generally assumed to be linear. This assumption is based on two requirements: (1) that the light output of the scintillator is proportional to the energy of the incident radiation; (2) that the electrical pulse produced by the photomultiplier tube is proportional to the emitted scintillation light. The linearity assumption is usually a good rough approximation, although deviations can occur (especially pronounced for particles heavier than the proton at low energies).

Resistance and good behavior under high-temperature, high-vibration environments is especially important for applications such as oil exploration (wireline logging, measurement while drilling). For most scintillators, light output and scintillation decay time depends on the temperature. This dependence can largely be ignored for room-temperature applications since it is usually weak. The dependence on the temperature is also weaker for organic scintillators than it is for inorganic crystals, such as NaI-Tl or BGO. Strong dependence of decay time on the temperature in BGO scintillator is used for remote monitoring of temperature in vacuum environment. The coupled PMTs also exhibit temperature sensitivity, and can be damaged if submitted to mechanical shock. Hence, high temperature rugged PMTs should be used for high-temperature, high-vibration applications.

The time evolution of the number of emitted scintillation photons N in a single scintillation event can often be described by  linear superposition of one or two exponential decays. For two decays, we have the form:

where τf and τs are the fast (or prompt) and the slow (or delayed) decay constants.
Many scintillators are characterized by 2 time components: one fast (or prompt), the other slow (or delayed). While the fast component usually dominates, the relative amplitude A and B of the two components depend on the scintillating material. Both of these components can also be a function of the energy loss dE/dx. In cases where this energy loss dependence is strong, the overall decay time constant varies with the type of incident particle. Such scintillators enable pulse shape discrimination, i.e., particle identification based on the decay characteristics of the PMT electric pulse. For instance, when BaF2 is used, γ rays typically excite the fast component, while α particles excite the slow component: it is thus possible to identify them based on the decay time of the PMT signal.

Types of scintillators

Organic crystals
Organic scintillators are aromatic hydrocarbon compounds which contain benzene ring structures interlinked in various ways. Their luminescence typically decays within a few nanoseconds.

Some organic scintillators are pure crystals. The most common types are anthracene (, decay time ≈30 ns), stilbene (, 4.5 ns decay time), and naphthalene (, few ns decay time). They are very durable, but their response is anisotropic (which spoils energy resolution when the source is not collimated), and they cannot be easily machined, nor can they be grown in large sizes; hence they are not very often used. Anthracene has the highest light output of all organic scintillators and is therefore chosen as a reference: the light outputs of other scintillators are sometimes expressed as a percent of anthracene light.

Organic liquids
These are liquid solutions of one or more organic scintillators in an organic solvent. The typical solutes are fluors such as p-terphenyl (), PBD (), butyl PBD (), PPO (), and wavelength shifter such as POPOP (). The most widely used solvents are toluene, xylene, benzene, phenylcyclohexane, triethylbenzene, and decalin. Liquid scintillators are easily loaded with other additives such as wavelength shifters to match the spectral sensitivity range of a particular PMT, or 10B to increase the neutron detection efficiency of the scintillation counter itself (since 10B has a high interaction cross section with thermal neutrons). Newer approaches combine several solvents or load different metals to achieve identification of incident particles. For many liquids, dissolved oxygen can act as a quenching agent and lead to reduced light output, hence the necessity to seal the solution in an oxygen-free, airtight enclosure.

Plastic scintillators

The term "plastic scintillator" typically refers to a scintillating material in which the primary fluorescent emitter, called a fluor, is suspended in the base, a solid polymer matrix.  While this combination is typically accomplished through the dissolution of the fluor prior to bulk polymerization, the fluor is sometimes associated with the polymer directly, either covalently or through coordination, as is the case with many Li6 plastic scintillators. Polyethylene naphthalate has been found to exhibit scintillation by itself without any additives and is expected to replace existing plastic scintillators due to higher performance and lower price. The advantages of plastic scintillators include fairly high light output and a relatively quick signal, with a decay time of 2–4 nanoseconds, but perhaps the biggest advantage of plastic scintillators is their ability to be shaped, through the use of molds or other means, into almost any desired form with what is often a high degree of durability. Plastic scintillators are known to show light output saturation when the energy density is large (Birks' Law).

Bases
The most common bases used in plastic scintillators are the aromatic plastics, polymers with aromatic rings as pendant groups along the polymer backbone, amongst which polyvinyltoluene (PVT) and polystyrene (PS) are the most prominent. While the base does fluoresce in the presence of ionizing radiation, its low yield and negligible transparency to its own emission make the use of fluors necessary in the construction of a practical scintillator. Aside from the aromatic plastics, the most common base is polymethylmethacrylate (PMMA), which carries two advantages over many other bases: high ultraviolet and visible light transparency and mechanical properties and higher durability with respect to brittleness.  The lack of fluorescence associated with PMMA is often compensated through the addition of an aromatic co-solvent, usually naphthalene.  A plastic scintillator based on PMMA in this way boasts transparency to its own radiation, helping to ensure uniform collection of light.

Other common bases include polyvinyl xylene (PVX) polymethyl, 2,4-dimethyl,  2,4,5-trimethyl styrenes, polyvinyl diphenyl, polyvinyl naphthalene, polyvinyl tetrahydronaphthalene, and copolymers of these and other bases.

Fluors
Also known as luminophors, these compounds absorb the scintillation of the base and then emit at larger wavelength, effectively converting the ultraviolet radiation of the base into the more easily transferred visible light.  Further increasing the attenuation length can be accomplished through the addition of a second fluor, referred to as a spectrum shifter or converter, often resulting in the emission of blue or green light.

Common fluors include polyphenyl hydrocarbons, oxazole and oxadiazole aryls, especially, n-terphenyl (PPP), 2,5-diphenyloxazole (PPO), 1,4-di-(5-phenyl-2-oxazolyl)-benzene (POPOP), 2-phenyl-5-(4-biphenylyl)-1,3,4-oxadiazole (PBD),  and 2-(4'-tert-butylphenyl)-5-(4''-biphenylyl)-1,3,4-oxadiazole (B-PBD).

Inorganic crystals

Inorganic scintillators are usually crystals grown in high temperature furnaces, for example, alkali metal halides, often with a small amount of activator impurity. The most widely used is  (thallium-doped sodium iodide); its scintillation light is blue. Other inorganic alkali halide crystals are: , , (pure), , , . Some non-alkali crystals include: BGO, , , , , ,  (), , . (For more examples, see also phosphors).

Newly developed products include , lanthanum chloride doped with cerium, as well as a cerium-doped lanthanum bromide, . They are both very hygroscopic (i.e., damaged when exposed to moisture in the air) but offer excellent light output and energy resolution (63 photons/keV γ for  versus 38 photons/keV γ for ), a fast response (16 ns for  versus 230 ns for ), excellent linearity, and a very stable light output over a wide range of temperatures. In addition LaBr3(Ce) offers a higher stopping power for γ rays (density of 5.08 g/cm3 versus 3.67 g/cm3 for ). LYSO () has an even higher density (7.1 g/cm3, comparable to ), is non-hygroscopic, and has a higher light output than  (32 photons/keV γ), in addition to being rather fast (41 ns decay time versus 300 ns for ).

A disadvantage of some inorganic crystals, e.g., NaI, is their hygroscopicity, a property which requires them to be housed in an airtight container to protect them from moisture.  and BaF2 are only slightly hygroscopic and do not usually need protection. CsF, , ,  are hygroscopic, while , , , and  are not.

Inorganic crystals can be cut to small sizes and arranged in an array configuration so as to provide position sensitivity. Such arrays are often used in medical physics or security applications to detect X-rays or γ rays: high-Z, high density materials (e.g. LYSO, BGO) are typically preferred for this type of applications.

Scintillation in inorganic crystals is typically slower than in organic ones, ranging typically from 1.48 ns for  to 9000 ns for . Exceptions are  (~5 ns), fast  (0.7 ns; the slow component is at 630 ns), as well as the newer products (, 28 ns; , 16 ns; , 41 ns).

For the imaging application, one of the advantage of inorganic crystals is very high light yield. Some high light yield scintillators above 100,000 photons/MeV at 662 keV are very recently reported for , , and .

Many semiconductor scintillator phosphors are known, such as ZnS(Ag) (mentioned in the history section), CdS(Ag), ZnO(Zn), ZnO(Ga), CdS(In), ZnSe(O), and ZnTe(O), but none of these are available as single crystals. CdS(Te) and ZnSe(Te) have been commercially available in single crystal form, but their luminosity is partially quenched at room temperature.

GaAs(Si,B) is a recently discovered cryogenic semiconductor scintillator with high light output in the infra-red and apparently no afterglow. In combination with ultra-low noise cryogenic photodetectors it is the target in experiments to detect rare, low-energy electronic excitations from interacting dark matter.

Gaseous scintillators
Gaseous scintillators consist of nitrogen and the noble gases helium, argon, krypton, and xenon, with helium and xenon receiving the most attention. The scintillation process is due to the de-excitation of single atoms excited by the passage of an incoming particle. This de-excitation is very rapid (~1 ns), so the detector response is quite fast. Coating the walls of the container with a wavelength shifter is generally necessary as those gases typically emit in the ultraviolet and PMTs respond better to the visible blue-green region. In nuclear physics, gaseous detectors have been used to detect fission fragments or heavy charged particles.

Glasses
The most common glass scintillators are cerium-activated lithium or boron silicates. Since both lithium and boron have large neutron cross-sections, glass detectors are particularly well suited to the detection of thermal (slow) neutrons. Lithium is more widely used than boron since it has a greater energy release on capturing a neutron and therefore greater light output. Glass scintillators are however sensitive to electrons and γ rays as well (pulse height discrimination can be used for particle identification). Being very robust, they are also well-suited to harsh environmental conditions. Their response time is ≈10 ns, their light output is however low, typically ≈30% of that of anthracene.

Solution-based perovskite scintillators
Scintillation properties of organic-inorganic methylamonium (MA) lead halide perovskites under proton irradiation were first reported by Shibuya et al. in 2002  and the first γ-ray pulse height spectrum, although still with poor energy resolution, was reported on () by van Eijk et al. in 2008 . Birowosuto at al.  studied the scintillation properties of 3-D and 2-D layered perovskites under X-ray excitation. MAPbBr3 () emits at 550 nm and MAPbI3 () at 750 nm which is attributed to exciton emission near the band gap of the compounds. In this first generation of Pb-halide perovskites the emission is strongly quenched at room temperature and less than 1000 ph/MeV survive. At 10 K however intense emission is observed and  write about yields up to 200000 ph/MeV. The quenching is attributed to the small e-h binding energy in the exciton that decreases for Cl to Br to I . Interestingly one may replace the organic MA group with Cs+ to obtain full inorganic CsPbX3 halide perovskites. Depending on the Cl, Br, I content the triplet X-ray excited exciton emission can be tuned from 430 nm to 700 nm . One may also dilute Cs with Rb to obtain similar tuning. Above very recent developments demonstrate that the organic-inorganic and all inorganic Pb-halide perovskites have various interesting scintillation properties. However, the recent two-dimensional perovskite single crystals  will be more favorable as they may have much larger Stokes shift up to 200 nm in comparison with CsPbBr3 quantum dot scintillators and this is essential to prevent self reabsorption for scintillators.

More recently, a new material class first reported by Professor Biwu Ma's research group, called 0D organic metal halide hybrid (OMHH), an extension of the perovskite materials. This class of materials exhibits strong exciton binding of hundreds of meV, resulting in their high photoluminescent quantum efficiency of almost unity. Their large stoke shift and reabsorption-free properties make them desirable. Their potential applications for scintillators have been reported by the same group, and others. In 2020,(C38H34P2)MnBr4 was reported to have a light yield up to 80 000 Photon/MeV despite its low Z compared to traditional all inorganic. Impressive light yields from other 0D OMHH have been reported. There is a great potential to realize new generation scintillators from this material class. However, they are limited by their relatively long response time in microseconds, which is an area of intense research.

Physics of scintillation

Organic scintillators
Transitions made by the free valence electrons of the molecules are responsible for the production of scintillation light in organic crystals. These electrons are associated with the whole molecule rather than any particular atom and occupy the so-called -molecular orbitals. The ground state S0 is a singlet state above which are the excited singlet states (S*,  the lowest triplet state (T0), and its excited levels (T*,  A fine structure corresponding to molecular vibrational modes is associated with each of those electron levels. The energy spacing between electron levels is ≈1 eV; the spacing between the vibrational levels is about 1/10 of that for electron levels.

An incoming particle can excite either an electron level or a vibrational level. The singlet excitations immediately decay (< 10 ps) to the S* state without the emission of radiation (internal degradation). The S* state then decays to the ground state S0 (typically to one of the vibrational levels above S0) by emitting a scintillation photon. This is the prompt component or fluorescence. The transparency of the scintillator to the emitted photon is due to the fact that the energy of the photon is less than that required for an S0 → S* transition (the transition is usually being to a vibrational level above S0).

When one of the triplet states gets excited, it immediately decays to the T0 state with no emission of radiation (internal degradation). Since the T0 → S0 transition is very improbable, the T0 state instead decays by interacting with another T0 molecule:

and leaves one of the molecules in the S* state, which then decays to S0 with the release of a scintillation photon. Since the T0-T0 interaction takes time, the scintillation light is delayed: this is the slow or delayed component (corresponding to delayed fluorescence). Sometimes, a direct T0 → S0 transition occurs (also delayed), and corresponds to the phenomenon of phosphorescence. Note that the observational difference between delayed-fluorescence and phosphorescence is the difference in the wavelengths of the emitted optical photon in an S* → S0 transition versus a T0 → S0 transition.

Organic scintillators can be dissolved in an organic solvent to form either a liquid or plastic scintillator. The scintillation process is the same as described for organic crystals (above); what differs is the mechanism of energy absorption: energy is first absorbed by the solvent, then passed onto the scintillation solute (the details of the transfer are not clearly understood).

Inorganic scintillators
The scintillation process in inorganic materials is due to the electronic band structure found in crystals and is not molecular in nature as is the case with organic scintillators. An incoming particle can excite an electron from the valence band to either the conduction band or the exciton band (located just below the conduction band and separated from the valence band by an energy gap; see picture). This leaves an associated hole behind, in the valence band. Impurities create electronic levels in the forbidden gap. The excitons are loosely bound electron-hole pairs which wander through the crystal lattice until they are captured as a whole by impurity centers. The latter then rapidly de-excite by emitting scintillation light (fast component). The activator impurities are typically chosen so that the emitted light is in the visible range or near-UV where photomultipliers are effective. The holes associated with electrons in the conduction band are independent from the latter. Those holes and electrons are captured successively by impurity centers exciting certain metastable states not accessible to the excitons. The delayed de-excitation of those metastable impurity states again results in scintillation light (slow component).

BGO (bismuth germanium oxide)  is a pure inorganic scintillator without any activator impurity. There, the scintillation process is due to an optical transition of the  ion, a major constituent of the crystal. In tungstate scintillators  and  the emission is due to radiative decay of self-trapped excitons.

The scintillation process in GaAs doped with silicon and boron impurities is different from conventional scintillators in that the silicon n-type doping provides a built-in population of delocalized electrons at the bottom of the conduction band. Some of the boron impurity atoms reside on arsenic sites and serve as acceptors. A scintillation photon is produced whenever an acceptor atom such as boron captures an ionization hole from the valence band and that hole recombines radiatively with one of the delocalized electrons. Unlike many other semiconductors, the delocalized electrons provided by the silicon are not "frozen out" at cryogenic temperatures. Above the Mott transition concentration of  free carriers per cm3, the "metallic" state is maintained at cryogenic temperatures because mutual repulsion drives any additional electrons into the next higher available energy level, which is in the conduction band. The spectrum of photons from this process is centered at 930 nm (1.33 eV) and there are three other emission bands centered at 860, 1070, and 1335 nm from other minor processes. Each of these emission bands has a different luminosity and decay time. The high scintillation luminosity is surprising because (1) with a refractive index of about 3.5, escape is inhibited by total internal reflection and (2) experiments at 90K report narrow-beam infrared absorption coefficients of several per cm. Recent Monte Carlo and Feynman path integral calculations have shown that the high luminosity could be explained if most of the narrow beam absorption is actually a novel optical scattering from the conduction electrons with a cross section of about 5 x 10–18 cm2 that allows scintillation photons to escape total internal reflection. This cross section is about 107 times larger than Thomson scattering but comparable to the optical cross section of the conduction electrons in a metal mirror.

Gases
In gases, the scintillation process is due to the de-excitation of single atoms excited by the passage of an incoming particle (a very rapid process: ≈1 ns).

Response to various radiations

Heavy ions
Scintillation counters are usually not ideal for the detection of heavy ions for three reasons:
 the very high ionizing power of heavy ions induces quenching effects which result in a reduced light output (e.g. for equal energies, a proton will produce 1/4 to 1/2 the light of an electron, while alphas will produce only about 1/10 the light);
 the high stopping power of the particles also results in a reduction of the fast component relative to the slow component, increasing detector dead-time;
 strong non-linearities are observed in the detector response especially at lower energies.

The reduction in light output is stronger for organics than for inorganic crystals. Therefore, where needed, inorganic crystals, e.g. ,  (typically used in thin sheets as α-particle monitors), , should be preferred to organic materials. Typical applications are α-survey instruments, dosimetry instruments, and heavy ion dE/dx detectors. Gaseous scintillators have also been used in nuclear physics experiments.

Electrons
The detection efficiency for electrons is essentially 100% for most scintillators. But because electrons can make large angle scatterings (sometimes backscatterings), they can exit the detector without depositing their full energy in it. The back-scattering is a rapidly increasing function of the atomic number Z of the scintillator material. Organic scintillators, having a lower Z than inorganic crystals, are therefore best suited for the detection of low-energy (< 10 MeV) beta particles. The situation is different for high energy electrons: since they mostly lose their energy by bremsstrahlung at the higher energies, a higher-Z material is better suited for the detection of the bremsstrahlung photon and the production of the electromagnetic shower which it can induce.

Gamma rays

High-Z materials, e.g. inorganic crystals, are best suited for the detection of gamma rays. The three basic ways that a gamma ray interacts with matter are: the photoelectric effect, Compton scattering, and pair production. The photon is completely absorbed in photoelectric effect and pair production, while only partial energy is deposited in any given Compton scattering. The cross section for the photoelectric process is proportional to Z5, that for pair production proportional to Z2, whereas Compton scattering goes roughly as Z. A high-Z material therefore favors the former two processes, enabling the detection of the full energy of the gamma ray. If the gamma rays are at higher energies (>5 MeV), pair production dominates.

Neutrons
Since the neutron is not charged it does not interact via the Coulomb force and therefore does not ionize the scintillation material. It must first transfer some or all of its energy via the strong force to a charged atomic nucleus. The positively charged nucleus then produces ionization. Fast neutrons (generally >0.5 MeV ) primarily rely on the recoil proton in (n,p) reactions; materials rich in hydrogen, e.g. plastic scintillators, are therefore best suited for their detection. Slow neutrons rely on nuclear reactions such as the (n,γ) or (n,α) reactions, to produce ionization. Their mean free path is therefore quite large unless the scintillator material contains nuclides having a high cross section for these nuclear reactions such as 6Li or 10B. Materials such as LiI(Eu) or glass silicates are therefore particularly well-suited for the detection of slow (thermal) neutrons.

List of inorganic scintillators
The following is a list of commonly used inorganic crystals:
  or barium fluoride:  contains a very fast and a slow component. The fast scintillation light is emitted in the UV band (220 nm) and has a 0.7 ns decay time (smallest decay time for any scintillator), while the slow scintillation light is emitted at longer wavelengths (310 nm) and has a 630 ns decay time. It is used for fast timing applications, as well as applications for which pulse shape discrimination is needed. The light yield of  is about 12 photons/keV.  is not hygroscopic.
  or bismuth germanate: bismuth germanate has a higher stopping power, but a lower optical yield than . It is often used in coincidence detectors for detecting back-to-back gamma rays emitted upon positron annihilation in positron emission tomography machines.
  or cadmium tungstate: a high density, high atomic number scintillator with a very long decay time (14 μs), and relatively high light output (about 1/3 of that of ).  is routinely used for X-ray detection (CT scanners). Having very little 228Th and 226Ra contamination, it is also suitable for low activity counting applications.
  or calcium fluoride doped with europium: The material is not hygroscopic, has a 940 ns decay time, and is relatively low-Z. The latter property makes it ideal for detection of low energy β particles because of low backscattering, but not very suitable for γ detection. Thin layers of  have also been used with a thicker slab of  to make phoswiches capable of discriminating between α, β, and γ particles.
  or calcium tungstate: exhibits long decay time 9 μs and short wavelength emission with maximum at 420 nm matching sensitivity curve of bialkali PMT. The light yield and energy resolution of the scintillator (6.6% for 137Cs) is comparable with that of .
 : undoped cesium iodide emits predominantly at 315 nm, is only slightly hygroscopic, and has a very short decay time (16 ns), making it suitable for fast timing applications. The light output is quite low at room temperature, however, it significantly increases with cooling.
  or cesium iodide doped with sodium: the crystal is less bright than , but comparable in light output to . The wavelength of maximum emission is at 420 nm, well matched to the photocathode sensitivity of bialkali PMTs. It has a slightly shorter decay time than  (630 ns versus 1000 ns for ).  is hygroscopic and needs an airtight enclosure for protection against moisture.
  or cesium iodide doped with thallium: these crystals are one of the brightest scintillators. Its maximum wavelength of light emission is in the green region at 550 nm.  is only slightly hygroscopic and does not usually require an airtight enclosure.
 GaAs or gallium arsenide (suitably doped with silicon and boron impurities) is a cryogenic n-type semiconductor scintillator with a low cryogenic bandgap (1.52 eV) and high light output (100 photons/keV) in the infra-red (930 nm). The absence of thermally stimulated luminescence is evidence for the absence of afterglow, which makes it attractive for detecting rare, low energy electronic excitations from interacting dark matter. Large (5 kg) high-quality crystals are commercially grown for electronic applications.
  or gadolinium oxysulfide has a high stopping power due to its relatively high density (7.32 g/cm3) and the high atomic number of gadolinium. The light output is also good, making it useful as a scintillator for x-ray imaging applications.
  (or lanthanum bromide doped with cerium): a better (novel) alternative to ; denser, more efficient, much faster (having a decay time about ~20ns), offers superior energy resolution due to its very high light output. Moreover, the light output is very stable and quite high over a very wide range of temperatures, making it particularly attractive for high temperature applications. Depending on the application, the intrinsic activity of 138La can be a disadvantage.  is very hygroscopic.
  (or lanthanum chloride doped with cerium): very fast, high light output.  is a cheaper alternative to . It is also quite hygroscopic.
  or lead tungstate: due to its high-Z,  is suitable for applications where a high stopping power is required (e.g. γ ray detection).
  or lutetium iodide.
  or lutetium oxyorthosilicate (): used in positron emission tomography because it exhibits properties similar to bismuth germanate (), but with a higher light yield. Its only disadvantage is the intrinsic background from the beta decay of natural 176Lu.
  (): comparable in density to , but much faster and with much higher light output; excellent for medical imaging applications.  is non-hygroscopic.
  or sodium iodide doped with thallium:  is by far the most widely used scintillator material. It is available in single crystal form or the more rugged polycrystalline form (used in high vibration environments, e.g. wireline logging in the oil industry). Other applications include nuclear medicine, basic research, environmental monitoring, and aerial surveys.  is very hygroscopic and needs to be housed in an airtight enclosure.
  or yttrium aluminum garnet:  is non-hygroscopic. The wavelength of maximum emission is at 550 nm, well-matched to red-resistive PMTs or photo-diodes. It is relatively fast (70 ns decay time). Its light output is about 1/3 of that of . The material exhibits some properties that make it particularly attractive for electron microscopy applications (e.g. high electron conversion efficiency, good resolution, mechanical ruggedness and long lifetime).
  or zinc sulfide:  is one of the older inorganic scintillators (the first experiment making use of a scintillator by Sir William Crookes (1903) involved a ZnS screen). It is only available as a polycrystalline powder, however. Its use is therefore limited to thin screens used primarily for α particle detection.
  or zinc tungstate is similar to  scintillator exhibiting long decay constant 25 μs and slightly lower light yield.

See also
 Gamma spectroscopy
 Liquid scintillation counting
 Scintillation counter
 Scintillating bolometer
 Neutron detection
 Total absorption spectroscopy

Notes

References

Sources

External links

 Crystal Clear Collaboration at CERN

 Scintillation crystals and their general characteristics

Photochemistry
Particle detectors

Ionising radiation detectors

Scintillator


Dinka este numele colectiv al unui grup etnic din Africa.

Dinka se mai poate referi la:

Diverse
 Limba Dinka, grup de limbi nilotice vorbite de oamenii grupului etnic Dinka
 Dinka (strugure), soi de viță de vie și vin originar din Ungaria
 Dinka (DJ), disc jockey elvețian
 Shri Dinka murti, animal sacru și personaj Ganesha în hinduism

Prenume și nume de familie
 Berhanu Dinka (1935–2013), diplomat și economist etiopian
 Tesfaye Dinka, politician și prim ministru al Etiopiei
 Dinka Džubur (), actriță, model și realizatoare de filme australiană de origine croată.

Nume proprii

Dinka (dezambiguizare)


Slovačka Wikipedija (slo. Slovenská Wikipédia), inačica Wikipedije na slovačkom jeziku. Započeta je u rujnu 2003. godine, a aktivnom je postala u ljetu 2004. godine. U rujnu 2005. je prešla prag od 15.000 članaka, a prag od 50.000 članaka je prešla u kolovozu 2006. godine.

U svibnju 2018. godine je imala više od 225.000 članaka.

Galerija

Izvori

Vanjske poveznice
 Wikipedija na slovačkom jeziku

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Wikipedija na slovačkom jeziku


Melez dövüş sanatları, çeşitli dövüş sanatlarından teorileri ve teknikleri bir araya getirerek oluşturulmuş dövüş sanatları.

Karma dövüş sanatları gibi diğer terimler melez dövüş sanatları ile yakın anlama sahip olmakla birlikte karma dövüş sanatları veya KSS (Mixed Martial Arts) belirli müsabakalarda kullanılan bir mücadele sporuna atıfla kullanılmaktadır.

Bazı melez dövüş sanatları
 Kick Boks (Japonya'da geliştirilmiştir. Boks, Karate, Muay Thai, Tekvando karışımı)
 Kyuk Too Ki (Kore Kick Boksu)
 Kun Gek Do (Kore Melez Savaş Sanatı)
 Sip Kwon Do (Kore Melez Savaş Sanatı)
 Graice Jiu Jutsu (Brezilya'da geliştirilmiştir)
 Pars taktik savunma (Türk kendini koruma Eğitimi)
 Krav Maga (İsrail kendini koruma tekniği)
 Jieishudan (Birleşik Krallık'ta geliştirilmiştir)
 Kombato (Brezilya silahlı kuvvetlerince geliştirilmiş kendini koruma tekniği)
 Kajukenbo (Hawai'de geliştirilmiş Karate, Judo, Kenpo, Çin Boksu, Jujutsa'dan oluşmaktadır)
 Zen Do Kai (Avustralya'da geliştirilmiştir)
 Jeet Kune Do (Bruce Lee'nin geliştirdiği sistemdir)
 Kul Elkavi Do (Yüksel Yılmaz'ın geliştirdiği sistemdir)

Ayrıca bakınız
 Karma savaş sanatları

Dış bağlantılar
 Chi Kung Tao / Kulelkavido  Founder of Yuksel Yilmaz from Turkey; Turkish Fight System, fundamentally Jeet Kune Do
 Wikipedia Hybrid Martial Arts
 Krav Maga Academy Founder of Cetin Bulent from Turkey;Kmg System

Melez dövüş sanatları


II. Osman () ya da Genç Osman, divan edebiyatındaki mahlasıyla Farisî, tahttan indirildikten sonraki adıyla Osman Çelebi (3 Kasım 1604, İstanbul - 20 Mayıs 1622, İstanbul); 16. Osmanlı padişahı ve 95. İslam halifesidir. Babası I. Ahmed, annesi genel kanıya göre Mahfiruz Hatice Sultan'dır. II. Osman 13 yaşında iken, amcası Sultan I. Mustafa'nın tahttan indirilmesi üzerine Osmanlı tahtına oturdu. Annesi onun yetişmesi için çok titiz davrandı. II. Osman iyi bir terbiye ve tahsil gördü. Arapça ve Farsça öğrendi. Bazı batı kaynaklarında Latince, Yunanca ve İtalyanca gibi batı dillerini öğrendiği kaydedilirse de bunun doğru olma ihtimali olmadığı iddiasına karşın yabancı asıllı olan annesi tarafından bu dillere eğitildiği söylenir. Osmanlı şehzadeleri arasında en kültürlüsü olduğu belirtilir.

II. Osman, Fatih Sultan Mehmed devrine kadar yapıldığı gibi saray dışından, hür Müslüman olan Şeyhülislam Es'ad Efendi'nin ve Pertev Paşa'nın kızları ile evlendi. Yavuz Sultan Selim devrinden itibaren padişah saray dışından evlenmediği için bu davranış önemli bir değişiklik oldu. Kendisine planlarını uygulayacak bir sadrazam bulamadı.

Tarihte eşine az rastlanır bir şekilde tahttan indirilerek, çeşitli hakarete ve saldırılara maruz bırakıldıktan sonra Yedikule Zindanları'nda yeniçeriler tarafından boğularak öldürülen II. Osman, babası Sultan I. Ahmed'in yaptırdığı Sultanahmet Camii'nin yanındaki türbesine defnedildi. Tahta çıkar çıkmaz devlet erkânı içindeki üst düzey yetkilileri değiştiren, müderris ve kadıların atanma yetkilerini şeyhülislamdan aldı. Bir ayaklanmada öldürülen ilk padişah ve Osmanlı padişahları arasında en genç vefat eden padişahtır.

İran ilişkileri
Sultan II. Osman tahta çıktığı sırada Sadrazam Damat Halil Paşa, İran seferindeydi. Osmanlı ordusu Pul-i Şikeste'de yenilmesine rağmen, İranlılar, mukaddes saydıkları Erdebil şehrinin Osmanlılar'ın eline geçme ihtimali üzerine barış istediler. Serav sahrasında, daha önce iki devlet arasında imzalanan Nasuh Paşa Antlaşması baz alınarak imzalanan Serav Antlaşması'yla barış tekrar sağlandı (26 Eylül 1618).

Otuz Yıl Savaşları

Kanuni zamanında başlayan Katoliklere karşı Protestanlara destek verme, Otuz Yıl Savaşları'nda devam etti. Özellikle Transilvanya'da çıkan Protestan isyanında, Osmanlı'nın büyük etkisi vardı.

İtalya ve Akdeniz seferi
Damat Halil Paşa komutasındaki Osmanlı donanması 1620 yazında Akdeniz seferine çıktı. İstanbul'dan ayrıldıktan sonra Navarin'e gelen donanma, buradan da kuzeye, Adriyatik'e doğru yöneldi. Dıraç'da iki İtalyan gemisini ele geçirdikten sonra İtalya'ya asker çıkardı ve İspanyollar'a ait olan liman şehri Manfredonia'yı ele geçirdi.

Lehistan seferi

Osmanlı Devleti ile Lehistan arasında bir dostluk mevcuttu. Dinyester ırmağı iki ülke arasında sınır oluşturuyordu. Osmanlı-Avusturya savaşlarında Lehistan ilişkileri gerginleştiyse de barış bozulmamıştı. Fakat askeri birliklerin geçimini Lehistan'a yaptığı akınlarla sağlayan Kırım Hanı, barışa aykırı hareket ediyordu. Bunun yanı sıra Lehliler Boğdan işlerine müdahaleden geri kalmadıkları gibi, Boğdan'a ait Hotin kalesini işgal etmişlerdi (1617). Ayrıca Eflak ve Erdel'in içişlerine müdahale etmeye devam ediyorlardı. Bu olaylar üzerine II. Osman, kendisine yapılan muhalefetlere rağmen Lehistan seferine karar verdi. Bu arada Özi Beylerbeyi İskender Paşa komutasındaki birlikler, Prut kıyısında bulunan Yaş'ta, Lehlileri bozguna uğratmıştı (Eylül 1620).

II. Osman, 1621'de Lehistan Seferi'ne çıktı. Lehler yeni ve daha büyük bir ordu meydana getirme çabasındaydılar. Avusturya'dan yardım alarak ordularını takviye ettiler. Osmanlı Ordusu 2 Eylül 1621'de Hotin önlerine geldi. Kale kuşatıldı ve Hotin Kalesi önlerinde yapılan meydan savaşında, düşman siperlerinin ele geçirilememesi, askerlerin şevk ve heyecanını oldukça yıprattı. Yeniçerilerin de kendilerini tam olarak savaşa vermemeleri, bu savaşın kesin bir netice ile sonuçlanmamasına yol açtı. Lehistan elçilerinin savaşa kendilerinin neden olduklarını bildirmesi üzerine Hotin Antlaşması yapılarak sefere son verildi (29 Eylül 1621). Antlaşmaya göre Lehler ve Osmanlılar birbirlerinin topraklarına saldırmayacak, Lehistan eskiden olduğu gibi Kırım Hanı'na 40.000 düka altın verecekti.

Yenilik hareketleri
II. Osman, Lehistan seferindeki başarısızlığının sebebi olarak askerin gayretsizliğini görüyordu. Askeri alanda bazı yenilikler yapma fikri böylece gelişti. İşe Kapıkulu Ocakları ile başladı. Yaptırdığı sayımda, asker sayısının maaş defterindeki kişi sayısından az olduğunu anlayınca fazladan para vermeyi kesti. Bu durum da, daha önce fazladan gelen paraları kendi ceplerine atan zabitlerin, II. Osman'a düşman olmalarına yol açtı. II. Osman'ın reformculuğuna dair anlatılanların çoğu 19. yüzyıldan itibaren konuyu ele alan bazı tarihçilerin kendi anlatımları ile ilgilidir. II. Osman'ın yapmak istediği reformlar olarak sunulanlar kendi devrinin kaynaklarında çoğunlukla yer almamaktadır. II. Osman'a atfedilen birçok reform düşüncesi 19. yüzyılda Mizancı Murad ile yazılmaya başlanmış olup orijinal bilgiye dayanmadan sunulmuştur. İsmail Hami Danişmend de II. Osman'ın başkenti Anadolu'ya taşımak istediğini, orduyu Türk unsurlarla yeniden kurmak istediğini, din adamlarını devlet işlerinden uzaklaştırmayı düşündüğünü, kıyafette değişiklikler tasarladığını ve daha başka yenilikler planladığını iddia etmekteyse de bunların çoğu devrin kaynaklarında yer almamaktadır. II. Osman'ın ordu ile ilgili birtakım düzenlemeler yapmak istediği bilinmekteyse de içeriği hakkında yeterince bilgi yoktur. Nev'î mahlasını kullanan Hüseyin İbn-i Sefer, "Sebeb-i Halâs-ı Mustafa Han" eserinde "Saâdetli Pâdişâh, yeniçeri ve sipah tâifesini kırıp, Etrâkten sekbân ve Türkmen'den cündî yazmak havasına düşüp Anadolu semtine geçmeğe hazır ve âmâde idi" der. İsmail Hami Danişmend'in, Osmanlı Tarihi Kronolojisi'ne göre II. Osman'ın yapmak istediği yenilikler şöyleydi:
 Artık iyice bozulmaya başlayan ve her geçen gün devletin başına iş açan yeniçeri ve sipahi ocaklarını ortadan kaldırarak, bunların yerine Anadolu, Suriye ve Mısır Türkleri'nden oluşan yeni bir ordu kurmak.
 Dönme ve devşirmelerle dolmuş devlet mekanizmasını temizlemek, yerlerine Türk milletinden kişiler getirmek.
 Osmanlı İmparatorluğu'nun başkentini İstanbul'dan Anadolu'ya, büyük olasılıkla bir Türk şehri olan Bursa'ya taşımak.
 İlmiye Sınıfı'nın artık yozlaşmaya başlaması nedeniyle, onların ekonomik ve siyasi güçlerini kırıp devlet üzerindeki etkilerini yok etmek.
 Saray geleneklerini değiştirerek artık padişah ve yakınlarının devşirmelerle evlilik yapması yerine Türk ailelerinden kız almasını sağlamak.
 Giysilerde değişiklikler yaparak eski gösterişli kavuk ve kaftanlar yerine daha yalın giysilerin giyilmesini sağlamak.
 Fatih Sultan Mehmet'in ve Kanuni Sultan Süleyman'ın yaptıkları yasaları yeniden düzenleyerek, imparatorluğun yeni koşullarına uydurmak.

II. Osman'ın Halep, Erzurum, Şam ve Mısır Beylerbeylerine asker yazdırmak için gizli bir irade gönderdiğinin sarayda adamları olan yeniçeriler tarafından öğrenilmesi, bardağı taşıran son damla oldu. II. Osman asker toplamak için Anadolu'ya bizzat kendisi gitmek istiyordu. Bu arada İstanbul'a, Dürzi lider Maanoğlu Fahreddin'in Lübnan'da bir isyan çıkardığı haberi geldi. II. Osman bunu bir fırsat bilerek, isyanı bastırmak için Anadolu'ya gideceğini söyledi. Ancak Sadrazam Dilaver Paşa ve Şeyhülislam Hocazade Esad Efendi, koskoca padişahın küçük bir isyan için Anadolu'ya gitmesine gerek olmadığını söyleyerek, II. Osman'ın Anadolu'ya geçmesini engellemeye çalıştılar. Başka bir çaresi kalmayan II. Osman, hacca gideceğini ilan etti. Daha önce hiçbir padişah hacca gitmemişti. Sadrazam Dilaver Paşa ve Şeyhülislam Es'ad Efendi çok uğraştılarsa da II. Osman fikrinde kararlıydı. Padişahın geçeceği güzergâh üzerindeki vilayetlerin beylerbeyleri haberdar edildi ve hazırlık yapmaları istendi. II. Osman'ın yanında 500 yeniçeri ve sipahi olacak, geri kalan asker İstanbul'un korunması için İstanbul'da kalacaktı. Sadrazam, defterdar, nişancı, rikab ümerası, gedikliler, 40 müteferrika ve 40 divan katibinin da hac kafilesinde yer alması planlamıştı.

İsyanın başlaması

II. Osman, ilk olarak kendisinin yerine I. Mustafa'nın tahta geçirilmesinde dahli olduğunu düşündüğü Damat Halil Paşa'yı azletti. Ardından da Hotin Seferi'ne giderken Şehzade Mehmed'i idam ettirdi. Halkı da huzursuz eden bu hataların ardından en son da gizlice ordu toplamak amacıyla hacca gideceği öğrenilince bu sefer yeniçeriler devreye girdi ve olay halk boyutundan çıkıp bir isyana dönüştü. Yeniçerilerin haberi aldıktan sonra takındıkları gaddarca tavır halk tarafından benimsenmemiştir.

II. Osman'ın öldürülmesi

Arpalıkları kesilen ulema ile geleceklerini tehdit altında hisseden yeniçeriler birleşerek Süleyman Ağa ile Hoca Ömer Efendi gibi bazı kişilerin idamını II. Osman'dan istediler ancak bu istekleri kabul edilmeyince 19 Mayıs 1622 tarihinde isyan başladı. Saraya giren isyancıların I. Mustafa'yı padişah ilan etmeleri üzerine bazı istekleri yerine getirildi ancak bunun da bir etkisi olmadı. Ulema başlangıçta I. Mustafa'ya biat etmek istemediyse de sonrasında biat etmek durumunda kalındı. Bu olaylar üzerine II. Osman Yeniçeriağası Ali Ağa'nın yanına gidip ona sığındı ve ondan Yeniçerileri ikna etmesini istedi. Yeniçerilerin karşısına geçerek onları ikna etmek isteyen Ali Ağa konuşturulmadı ve üzerine kılıçla saldırılıp parçalandı.

Ardından II. Osman'ı yakalayan isyancılar, onu beygire bindirip yol boyunca hakaretler ederek kötü davrandılar. İsyancılardan biri II. Osman'ın baldırlarını sıkıp ona küfrediyordu. Son durak olarak Yedikule Zindanları'na götürülen II. Osman, orada hapsedildi. Onu öldürmek isteyenlere karşı direnen II. Osman'ın hayaları sıkılarak etkisiz hale getirildi ve boynuna atılan kementle boğularak öldürüldü. Katillerin arasında yer alanlardan biri ise II. Osman'ın kulağını keserek I. Mustafa'nın annesine götürdü. Bu cinayetten I. Mustafa'nın annesi oldukça memnun kaldı. Naaşı babası Sultan Ahmed'in türbesine götürülüp gömüldü. Bu olaya Haile-i Osmaniye adı verilmiştir.

Ölümünden sonra
Ana madde: Abaza isyanları & Haile-i Osmaniye

Sultan II. Osman'ın ölümü oldukça büyük bir infiale yol açmıştır. Nitekim akabinde Abaza isyanları patlak vermiş ve imparatorluk anarşi dönemine I. Mustafa'nın da tahttan indirilmesi ile girmiş bulundu. I. Mustafa'dan sonra 11 yaşındaki IV. Murad tahta geçirildi. İstanbul sokakları adeta susmuyor ahali ve askerler her yerde Sultan Osman'ın ölümünde parmağı olan kişileri arıyordu. Bu isyanlar devletin bütün kıtalarına yayılmış bir biçimdeydi. IV. Murad'ın 1632'deki mutlak saltanatına kadar bu isyanlar bastırılamadı. Büyük bir görüş eğer Sultan IV. Murad meydana çıkmasaydı bu isyanların devamlılığı sonucu devletin parçalara bölünebileceğinin olası olduğunu destekler. Zira IV. Murad dönemine kadar devlet yeteneksizce yönetilmiş ve anarşi üstüne anarşiler yaşanmıştır. IV. Murad çok sevdiği abisinin ölümü üzerine oldukça üzülmüştü. Konya'da ağabeyinin ölümünde yer alan iki eski yeniçeriyi kalabalık arasında tanımış ve ikisini de 150 kilogramlık gürzü ile infaz etmiştir. II. Osman ölümü sonraki dönemlere de oldukça etki bırakmış ve ordunun devlet üzerinde etkisi artmıştı.

Hakkında yazılanlar

Sultan Osman Han Mersiyesi
Nef'i tarafından Sultan Osman'ın ölümü üzerine 1622'de yazılmıştır.Bir şâh-ı alîşan iken şâh-ı cihâna kıydılar.Gayretlü genç aslan iken şâh-ı cihâna kıydılar.Gâzi bahâdır hân idi Âli-neseb sultan idi.Nâmiyle Osman Han idi Şâh-ı cihâna kıydılar.Hükmetmeğe kâdir iken Emr-i Hakk'a nâzır ikenHacc itmeğe hâzır iken Şâh-ı cihâna kıydılar.Ey dil ciğerler oldu hûn derdim bir iken oldu on Kan ağladı eh-i fünûn şâh-ı cihâna kıydılar.Eşrât-ı sâatdir bu dem rûz-ı kıyâmetdir bu demKul'a nedâmetdir bu dem Şâh-ı cihâna kıydılar.Nef'i -1622-

Edebi yönü
'Farisî' mahlasıyla birçok şiir yazmıştır.Gülşen içre bitmedi bir gonce cana harsızDünyada hasıl değil nev-cühan ağyarsızKimi ol yarı benüm der kimisi dahi benümOrta yerde "farisi" avare kaldı yarsız (...)Nevruz olucak diller şad olamağa yaklaşdıDilde gam-u gussa ber-bad olmağa yaklaşdıVirane gönül varsa vecr-ü gam-i dilberdenMüsde ana ol mülk abad omağa yaklaşdıÜstüda dilber öğrendi vefa resminAşıklara lütfa mu'tad olmağa yaklaşdıÇok aşık-u meftunu var sen gibi şirinünFaris kulun emma ferhad olmağa yaklaşdıFarisî

Ailesi

Eşleri
 Ayşe Sultan- II. Osman'ın ikinci eşidir. Pertev Paşa'nın torunu olduğu bilinmektedir.
 Meylişah Hatun veya Fatma Züleyha Haseki - Şehzade Ömer'in annesidir. Aslen Arnavut bir asilzadedir. Şehzade Ömer'in ölümünden sonra bir süre Topkapı Sarayı'nda kalmamış, 2. Osman'ın tahttan indirilmesinden sonra da görümcesi Hanzade Sultan'ın yanında kalmıştır.
 Akile Hatun - Şeyhülislam Hocazade Esad Efendi'nin kızıydı.Şehzade Mustafa ve Zeynep Sultan'ın annesidir. Eşinin ölümünden sonra 1627 yılında ünlü şair Ganizade Nadir Efendi ile evlenmiştir.

Çocukları
 Şehzade Ömer (d. 20 Ekim 1621 - ö. Ocak 1622)
 Şehzade Mustafa (d. Kasım 1622 - ö. 1623)
 Zeynep Sultan (d. Kasım 1622 - ö. ?)

Popüler kültürdeki yeri
12 Kasım 2015'te başlayan Muhteşem Yüzyıl Kösem dizisinde II. Osman, Taner Ölmez tarafından canlandırılmıştır.

Kaynakça

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1604 doğumlular
İstanbul doğumlu devlet görevlileri
1622 yılında ölenler
17. yüzyılda Osmanlı padişahları
17. yüzyılda Osmanlılar
17. yüzyıl dini liderleri
Çocuk hükümdarlar
17. yüzyılda suçlar
Suikast sonucu ölen hükümdarlar
Suikast sonucu ölen Osmanlılar
İstanbul'da ölenler
İstanbul'da defnedilenler
Türk işkence kurbanları
Osmanlı İmparatorluğu duraklama dönemi
Tahttan indirilen Osmanlı padişahları
İki kutsal caminin hizmetkârları

II. Osman


Carl Momberg (* 20. Februar 1901 in Braunschweig; † 15. März 1988 ebenda) war ein deutscher Opernsänger (Bariton) und Regisseur.

Leben
Momberg arbeitete bis 1924 in der Konstruktion von Rechenmaschinen, bevor er in seiner Heimatstadt eine Ausbildung als Sänger absolvierte. In Braunschweig trat er erstmals 1926 auf. Von 1928 bis 1930 studierte er am Leipziger Konservatorium. Er spielte an Theatern in Görlitz, Halle und Weimar, trat bei den Händel-Festspielen in Halle und bei den Schlesischen Musikfesten auf. Von 1933 bis 1967 war er am Staatstheater Braunschweig engagiert, wo er als lyrischer Bariton in zahlreichen Opern und Operetten mitwirkte. Er war seit 1950 auch als Opernregisseur tätig und wirkte als Gesangslehrer. Zu seinen Schülern zählte Hans Günter Nöcker. Er wurde zum Ehrenmitglied des Staatstheaters Braunschweig ernannt.

Literatur
 Norman-Mathias Pingel: Momberg, Carl. In: Braunschweiger Stadtlexikon Ergänzungsband, Braunschweig 1996, S. 94f.

Opernsänger
Bariton
Ensemblemitglied der Oper Halle
Opernregisseur
Darstellender Künstler (Braunschweig)
Deutscher
Geboren 1901
Gestorben 1988
Mann

Carl Momberg


Mitsuru Ushijima () a fost un general japonez în timpul celui de-Al Doilea Război Chino-Japonez și în cel de-al Doilea Război Mondial. El a fost comandantul general al Armatei a 32-a, care a luptat în Bătălia de la Okinawa în ultimele etape ale războiului. Trupele lui Ushijima au fost înfrânte, iar la sfârșitul bătăliei generalul japonez s-a sinucis.

Note

Bibliografie

Legături externe

Nașteri în 1887
Decese în 1945
Generali japonezi
Militari care s-au sinucis

Mitsuru Ushijima


Ulusal Veri Değişim Formatı, Türkiye Tapu Kadastro Genel Müdürlüğü Bünyesinde Kurulan TAKBİS (Tapu Kadastro Bilgi Sistemi) Projesi Kapsamında; çeşitli programlarca üretilen harita bilgilerinin bütünlüğünün sağlanması amacıyla oluşturulmuş bir dosya biçimidir. Verileri XML biçiminde tutar. Nesnelerin grafik ve sözel bilgileri saklanabilir.
Bu veriler ayrı iki dosyada tutulmaktadır. Grafik veriler için "Geo_" ön eki, sözel veriler için "Tablo_" ön eki dosya adının başına eklenir.

Dış bağlantılar
 http://www.tkgm.gov.tr"

Ulusal Veri Değişim Formatı


"Enternasyonal" (Fransızca: L'Internationale, Rusça: Интернационал), orijinali Fransızca olan ve birçok dile çevrilen şarkı, marş.

Fransızca orijinali 1870 yılında Eugène Pottier tarafından yazılmıştır ve Pierre Degeyter tarafından 1888 yılında bestelenmiştir. Bu beste tüm dünyada geniş bir kabul görmüş ve diğer dillerdeki çevirilerde de bu besteye sadık kalınmıştır.

Marş, Komünist Enternasyonal (Komintern) tarafından işçi sınıfının marşı olarak kabul edilmiştir. Komintern selamı ile, sağ yumruk dirsekten kırık ve yumruk içi karşıya bakacak şekilde kaldırılarak söylenir.

Rusça versiyonu Arkady Kots tarafından 1902 yılında çevirilmiştir ve aynı yıl Paris'te Rusça yayınlanmakta olan Jizn adlı dergide yayınlanmıştır. Orijinali 6 kıta olan şiirin daha sonra geliştirilen Rusça versiyonu 3 kıtadan oluşur.

1918-1944 yılları arasında Sovyetler Birliği'nin millî marşı olmuştur. Şarkı aynı zamanda Sovyetler Birliği Komünist Partisi'nin de resmi marşıdır.

Orijinal Sözler

Dış bağlantılar

  Enternasyonal Özel Bölüm
 Enternasyonal'in Türkçe versiyonu
 83 Dilde Enternasyonal
 30 dilde şarkının indirilebilir formatı
  Şarkı hakkında belgesel film
 Sheffield Socialist Choir (mms://mayday.nodong.net/2001/music/Internationale-SheffieldSocialistChoir.wma)
 Erkin Özalp tarafından yapılan sözcüğü sözcüğüne (literal) çeviri
 https://focusonbelgium.be/en/facts/did-you-know-composer-internationale-was-belgian
 https://www.welt.de/vermischtes/prominente/article127084943/Ich-habe-die-Kommunisten-bezahlen-lassen.html
 https://www.marxists.org/history/etol/writers/gluckstein/2008/xx/internationale.html
 https://www.lemonde.fr/cinema/article/2005/04/08/siffloter-l-internationale-peut-couter-cher_636777_3476.html
 https://books.google.com.tr/books?id=OiGMPBfoqN8C&redir_esc=y
 http://www.sovmusic.ru/english/list.php?gold=no&category=inter&part=1
 http://feb-web.ru/feb/litenc/encyclop/le4/le4-5401.htm

Eski ulusal marşlar
Dini eleştiren şarkılar
Sosyalizm
Komünizm

Enternasyonal


Cueva de los Tayos (španjolski, "Špilja uljašica") je špilja smještena na istočnim padinama Anda u pokrajini Morona-Santiago u Ekvadoru. Ponekad se naziva Cueva de los Tayos de Coangos (Río Coangos je u blizini).

Opis
Cueva de los Tayos nalazi se u visokoj prašumi, 2 km južno od rijeke Santiago i 800 m zapadno od rijeke Coangos. Prema GPS mjerenju iz 2008. godine, njezina nadmorska visina je 539 metara iznad razine mora. Smještena na nadmorskoj visini od oko 800 metara unutar tankoslojnog vapnenca i škriljevca, glavni ulaz u Cueva de Los Tayos je unutar prašume na dnu suhe doline. Najveći od tri ulaza je 65 metara duboko okno koje vodi do 4.6 km dugih prostranih prolaza i komore dimenzija 90 m x 240 m. Špilja ima vertikalni raspon od 201 metara s najnižom točkom koja završava u sumpu.

Špilju koriste domorodački narod Shuar koji se svakog proljeća spušta u špilju koristeći ljestve od vinove loze i baklje od bambusa kako bi skupili mlade ptice uljarice ("guácharos" ili "tayos" na španjolskom). Špilja se spominje u pisanoj formi još od 1860. godine, a posjećivali su je tragači za zlatom i vojno osoblje 1960-ih.

Špilja se nalazi unutar Sindikalnog centra Coangos (koji su formirali domoroci).

Pristup špilji je ograničen. Potrebno je dobiti dozvolu (pristup i privremeni posjet) i platiti porez (određen za poboljšanje zajednica) u Sucúi, Ekvador, u Shuar Center Federation. (FICSH: Federación Interprovincial de Centros Shuar )

Zlato bogova
Ekspedicija u špilju iz 1969. opisana je u knjizi Pina Turolle iz 1970. Beyond the Andes. Erich von Däniken je u svojoj knjizi Zlato bogova iz 1973. napisao da je János Juan Móricz (1923. – 1991.) tvrdio da je istraživao Cueva de los Tayos 1969. i otkrio gomile zlata, neobične skulpture i metalnu knjižnicu. Rečeno je da se ti predmeti nalaze u umjetnim tunelima koje je stvorila izgubljena civilizacija uz pomoć izvanzemaljskih bića. Von Däniken je prethodno tvrdio u svojoj knjizi iz 1968., Kočije bogova?, da su izvanzemaljci bili uključeni u drevne civilizacije.

Ekspedicija BCRA iz 1976.
Kao rezultat tvrdnji objavljenih u von Dänikenovoj knjizi, istraživanje Cueva de los Tayos organizirao je Stan Hall iz Škotske 1976. godine. Jedno od najvećih i najskupljih istraživanja špilja ikad poduzetih, ekspedicija je uključivala više od stotinu ljudi, uključujući stručnjake iz raznih područja, britansko i ekvadorsko vojno osoblje, filmsku ekipu i bivšeg američkog astronauta Neila Armstronga. Tim je također uključivao osam iskusnih britanskih speleologa koji su temeljito istražili špilju i proveli precizno istraživanje kako bi izradili njezinu detaljnu kartu. Nije bilo dokaza o Von Dänikenovim egzotičnijim tvrdnjama, iako su neke fizičke značajke špilje bile približne njegovim opisima i pronađeni su neki predmeti od zoološkog, botaničkog i arheološkog interesa. Voditelj istraživanja susreo se s Moriczovim domaćim izvorom, koji je tvrdio da su istražili pogrešnu špilju i da je prava špilja tajna.

Izvori

Daljnje čitanje
 Frankland, John, "The Los Tayos Expedition" Caving International No 1, 1978
 AtlasGreat Caves of the World Cave Books, 1989, p. 58
 von Däniken, Erich, Gold of the Gods Bantam Books, 1974

Vanjske poveznice

 Nexus Magazine article
 Stan Hall's Goldlibrary website

Reljefni oblici u Ekvadoru
Špilje u Južnoj Americi

Cueva de los Tayos


Belirlenimsiz Turing makinesi, bulunduğu durumdan sonraki durum için birden fazla seçenek Turing makinasıdır. Makina aşağıdaki bileşenlerden oluşur:

 Bir veya birkaç şerit
 Şerit(ler)i okumak için kafa(lar)
 Geçiş tablosunu ve Turing makinesinin o anki durumunu içeren bir iç mantık

Belirlenimli Turing makinasından farklı olarak, belirlenimsiz Turing makinesi aynı durum için birkaç adım arasından seçim yapabilir. Başka bir deyişle, geçiş tablosunda aşağıdaki gibi girdiler olabilir:

Bu durumda, ilgili Turing makinesi d0 durumundayken ve 1 sembolünü görürken ister sağa ister sola gidebilir. İki çeşit belirlenimsizlik vardır:

 Melekimsi belirlenimsizlik: Bu tip bir belirlenimsizlikte, makine birkaç seçim arasından her zaman "doğru" olanı seçer.
 Şeytanî belirlenimsizlik: Bu tip belirlenimsizlikte ise makine birkaç seçim arasından her zaman "yanlış" olanı seçer.

Belirlenimsiz Turing makinesi, melekimsi bir belirlenimsizlik kullanır ve dolayısıyla her zaman kendini sonuca yaklaştıran seçimi yapacaktır. Melekimsi belirlenimsiz bir Turing makinasıyla polinomsal zamanda çözülebilen problemler NP kümesini oluşturur. Belirlenimsiz makina, belirlenimli bir Turing makinası ile simüle edilebileceği için belirlenimsiz makinanın çözebildiği problemler kümesi, belirlenimli makinanın çözebildiği problemler kümesine eşittir.

Hesaplama modelleri
Turing makinesi

Belirlenimsiz Turing makinesi


An autostereogram is a two-dimensional (2D) image that can create the optical illusion of a three-dimensional (3D) scene. Autostereograms use only one image to accomplish the effect while normal stereograms require two. The 3D scene in an autostereogram is often unrecognizable until it is viewed properly, unlike typical stereograms. Viewing any kind of stereogram properly may cause the viewer to experience vergence-accommodation conflict.

The optical illusion of an autostereogram is one of depth perception and involves stereopsis: depth perception arising from the different perspective each eye has of a three-dimensional scene, called binocular parallax.

Individuals with disordered binocular vision and who cannot perceive depth may require a wiggle stereogram to achieve a similar effect.

The simplest type of autostereogram consists of a horizontally repeating pattern with small changes throughout that looks like wallpaper. When viewed with proper vergence, the repeating patterns appear to float above or below the background. The well-known Magic Eye books feature another type of autostereogram called a random-dot autostereogram , similar to the first example, above. In this type of autostereogram, every pixel in the image is computed from a pattern strip and a depth map. A hidden 3D scene emerges when the image is viewed with the correct vergence.

Unlike normal stereograms, autostereograms do not require the use of a stereoscope. A stereoscope presents 2D images of the same object from slightly different angles to the left eye and the right eye, allowing us to reconstruct the original object via binocular disparity. When viewed with the proper vergence, an autostereogram does the same, the binocular disparity existing in adjacent parts of the repeating 2D patterns.

There are two ways an autostereogram can be viewed: wall-eyed and cross-eyed. Most autostereograms (including those in this article) are designed to be viewed in only one way, which is usually wall-eyed. Wall-eyed viewing requires that the two eyes adopt a relatively parallel angle, while cross-eyed viewing requires a relatively convergent angle. An image designed for wall-eyed viewing if viewed correctly will appear to pop out of the background, whereas if viewed cross-eyed it will instead appear as a cut-out behind the background and may be difficult to bring entirely into focus.

History
In 1593, Giambattista della Porta viewed one page of a book with one eye and another page with the other eye. He was able to read one of the pages, the other being invisible, and switch "the visual virtue" to read the other page, the first becoming invisible. This is an early example of dissociating vergence from accommodation—a necessary ability for seeing autostereograms. However, Porta saw competition between images viewed by the two eyes, binocular rivalry.

It was not until 1838 that the Charles Wheatstone published an example of cooperation between the images in the two eyes: stereopsis (binocular depth perception). He explained that the depth arose from differences in the horizontal positions of the images in the two eyes. He supported his explanation by showing flat, two-dimensional pictures with such horizontal differences, stereograms, separately to the left and right eyes through a stereoscope he invented based on mirrors. From such pairs of flat images, people experienced the illusion of depth.

In 1844, David Brewster discovered the "wallpaper effect". He noticed that when he stared at repeated patterns in wallpapers while varying his vergence, he could see them either behind the wall (with wall-eyed vergence) or in front of the wall (with cross-eyed vergence). This is the basis of wallpaper-style autostereograms.

In 1939 Boris Kompaneysky published the first, random-dot stereogram containing a hand-drawn image of the face of Venus, intended to be viewed with a device.

In 1959, Bela Julesz, vision scientist, psychologist, and MacArthur Fellow, invented random dot stereograms while working at Bell Laboratories on recognizing camouflaged objects from aerial pictures taken by spy planes. At the time, many vision scientists assumed that stereopsis required prior analysis of visible contours of images in each eye, but Julesz showed it occurs with images with no such visible contours in each of the eyes. The contours of the depth object become visible only after stereopsis had processed the differences in the horizontal positions of dots in the two eyes' images.

Japanese designer Masayuki Ito, following Julesz, created a single image stereogram in 1970 and Swiss painter Alfons Schilling created a handmade single-image stereogram in 1974, after creating more than one viewer and meeting with Julesz. Having experience with stereo imaging in holography, lenticular photography, and vectography, he developed a random-dot method based on closely spaced vertical lines in parallax.

In 1979, Christopher Tyler of Smith-Kettlewell Institute, a student of Julesz and a visual psychophysicist, combined the theories behind single-image wallpaper stereograms and random-dot stereograms (the work of Julesz and Schilling) to create the first black-and-white random-dot autostereogram with the assistance of computer programmer Maureen Clarke using Apple II and BASIC. Stork and Rocca published the first scholarly paper and provided software for generating random-dot stereograms. This type of autostereogram allows a person to see 3D shapes from a single 2D image without the aid of optical equipment. In 1991 computer programmer Tom Baccei and artist Cheri Smith created the first color random-dot autostereograms, later marketed as Magic Eye.

A computer procedure that extracts back the hidden geometry out of an autostereogram image was described by Ron Kimmel.
In addition to classical stereo it adds smoothness as an important assumption in the surface reconstruction.

In the late '90s many children's magazines featured autostereograms. Even gaming magazines like Nintendo Power had a section specifically made for these illusions.

How they work

Simple wallpaper

Stereopsis, or stereo vision, is the visual blending of two similar but not identical images into one, with resulting visual perception of solidity and depth. In the human brain, stereopsis results from complex mechanisms that form a three-dimensional impression by matching each point (or set of points) in one eye's view with the equivalent point (or set of points) in the other eye's view. Using binocular disparity, the brain derives the points' positions in the otherwise inscrutable z-axis (depth).

When the brain is presented with a repeating pattern like wallpaper, it has difficulty matching the two eyes' views accurately. By looking at a horizontally repeating pattern, but converging the two eyes at a point behind the pattern, it is possible to trick the brain into matching one element of the pattern, as seen by the left eye, with another (similar looking) element, beside the first, as seen by the right eye. With the typical wall-eyed viewing, this gives the illusion of a plane bearing the same pattern but located behind the real wall. The distance at which this plane lies behind the wall depends only on the spacing between identical elements.

Autostereograms use this dependence of depth on spacing to create three-dimensional images. If, over some area of the picture, the pattern is repeated at smaller distances, that area will appear closer than the background plane. If the distance of repeats is longer over some area, then that area will appear more distant (like a hole in the plane).

People who have never been able to perceive 3D shapes hidden within an autostereogram find it hard to understand remarks such as, "the 3D image will just pop out of the background, after you stare at the picture long enough", or "the 3D objects will just emerge from the background". It helps to illustrate how 3D images "emerge" from the background from a second viewer's perspective. If the virtual 3D objects reconstructed by the autostereogram viewer's brain were real objects, a second viewer observing the scene from the side would see these objects floating in the air above the background image.

The 3D effects in the example autostereogram are created by repeating the tiger rider icons every 140 pixels on the background plane, the shark rider icons every 130 pixels on the second plane, and the tiger icons every 120 pixels on the highest plane. The closer a set of icons are packed horizontally, the higher they are lifted from the background plane. This repeat distance is referred to as the depth or z-axis value of a particular pattern in the autostereogram. The depth value is also known as Z-buffer value.

The brain is capable of almost instantly matching hundreds of patterns repeated at different intervals in order to recreate correct depth information for each pattern. An autostereogram may contain some 50 tigers of varying size, repeated at different intervals against a complex, repeated background. Yet, despite the apparent chaotic arrangement of patterns, the brain is able to place every tiger icon at its proper depth.

Depth maps

Autostereograms where patterns in a particular row are repeated horizontally with the same spacing can be read either cross-eyed or wall-eyed. In such autostereograms, both types of reading will produce similar depth interpretation, with the exception that the cross-eyed reading reverses the depth (images that once popped out are now pushed in).

However, icons in a row do not need to be arranged at identical intervals. An autostereogram with varying intervals between icons across a row presents these icons at different depth planes to the viewer.  The depth for each icon is computed from the distance between it and its neighbor at the left. These types of autostereograms are designed to be read in only one way, either cross-eyed or wall-eyed. All autostereograms in this article are encoded for wall-eyed viewing, unless specifically marked otherwise. An autostereogram encoded for wall-eyed viewing will produce inverse patterns when viewed cross-eyed, and vice versa. Most Magic Eye pictures are also designed for wall-eyed viewing.

The wall-eyed depth map example autostereogram to the right encodes 3 planes across the x-axis. The background plane is on the left side of the picture. The highest plane is shown on the right side of the picture. There is a narrow middle plane in the middle of the x-axis. Starting with a background plane where icons are spaced at 140 pixels, one can raise a particular icon by shifting it a certain number of pixels to the left. For instance, the middle plane is created by shifting an icon 10 pixels to the left, effectively creating a spacing consisting of 130 pixels. The brain does not rely on intelligible icons which represent objects or concepts. In this autostereogram, patterns become smaller and smaller down the y-axis, until they look like random dots. The brain is still able to match these random dot patterns.

The distance relationship between any pixel and its counterpart in the equivalent pattern to the left can be expressed in a depth map. A depth map is simply a grayscale image which represents the distance between a pixel and its left counterpart using a grayscale value between black and white. By convention, the closer the distance is, the brighter the color becomes.

Using this convention, a grayscale depth map for the example autostereogram can be created with black, gray and white representing shifts of 0 pixels, 10 pixels and 20 pixels, respectively as shown in the greyscale example autostereogram. A depth map is the key to creation of random-dot autostereograms.

Random-dot

A computer program can take a depth map and an accompanying pattern image to produce an autostereogram. The program tiles the pattern image horizontally to cover an area whose size is identical to the depth map. Conceptually, at every pixel in the output image, the program looks up the grayscale value of the equivalent pixel in the depth map image, and uses this value to determine the amount of horizontal shift required for the pixel.

One way to accomplish this is to make the program scan every line in the output image pixel-by-pixel from left to right. It seeds the first series of pixels in a row from the pattern image. Then it consults the depth map to retrieve appropriate shift values for subsequent pixels. For every pixel, it subtracts the shift from the width of the pattern image to arrive at a repeat interval. It uses this repeat interval to look up the color of the counterpart pixel to the left and uses its color as the new pixel's own color.

Unlike the simple depth planes created by simple wallpaper autostereograms, subtle changes in spacing specified by the depth map can create the illusion of smooth gradients in distance. This is possible because the grayscale depth map allows individual pixels to be placed on one of 2n depth planes, where n is the number of bits used by each pixel in the depth map. In practice, the total number of depth planes is determined by the number of pixels used for the width of the pattern image. Each grayscale value must be translated into pixel space in order to shift pixels in the final autostereogram. As a result, the number of depth planes must be smaller than the pattern width.

The fine-tuned gradient requires a pattern image more complex than standard repeating-pattern wallpaper, so typically a pattern consisting of repeated random dots is used. When the autostereogram is viewed with proper viewing technique, a hidden 3D scene emerges. Autostereograms of this form are known as Random Dot Autostereograms.

Smooth gradients can also be achieved with an intelligible pattern, assuming that the pattern is complex enough and does not have big, horizontal, monotonic patches. A big area painted with monotonic color without change in hue and brightness does not lend itself to pixel shifting, as the result of the horizontal shift is identical to the original patch. The following depth map of a shark with smooth gradient produces a perfectly readable autostereogram, even though the 2D image contains small monotonic areas; the brain is able to recognize these small gaps and fill in the blanks (illusory contours). While intelligible, repeated patterns are used instead of random dots, this type of autostereogram is still known by many as a Random Dot Autostereogram, because it is created using the same process.

Animated

When a series of autostereograms are shown one after another, in the same way moving pictures are shown, the brain perceives an animated autostereogram. If all autostereograms in the animation are produced using the same background pattern, it is often possible to see faint outlines of parts of the moving 3D object in the 2D autostereogram image without wall-eyed viewing; the constantly shifting pixels of the moving object can be clearly distinguished from the static background plane. To eliminate this side effect, animated autostereograms often use shifting background in order to disguise the moving parts.

When a regular repeating pattern is viewed on a CRT monitor as if it were a wallpaper autostereogram, it is usually possible to see depth ripples. This can also be seen in the background to a static, random-dot autostereogram. These are caused by the sideways shifts in the image due to small changes in the deflection sensitivity (linearity) of the line scan, which then become interpreted as depth. This effect is especially apparent at the left hand edge of the screen where the scan speed is still settling after the flyback phase. On a TFT LCD, which functions differently, this does not occur and the effect is not present. Higher quality CRT displays also have better linearity and exhibit less or none of this effect.

Mechanisms for viewing

Much advice exists about seeing the intended three-dimensional image in an autostereogram. While some people may quickly see the 3D image in an autostereogram with little effort, others must learn to train their eyes to decouple eye convergence from lens focusing.

Not every person can see the 3D illusion in autostereograms. Because autostereograms are constructed based on stereo vision, persons with a variety of visual impairments, even those affecting only one eye, are unable to see the three-dimensional images.

People with amblyopia (also known as lazy eye) are unable to see the three-dimensional images. Children with poor or dysfunctional eyesight during a critical period in childhood may grow up stereoblind, as their brains are not stimulated by stereo images during the critical period. If such a vision problem is not corrected in early childhood, the damage becomes permanent and the adult will never be able to see autostereograms. It is estimated that some 1 percent to 5 percent of the population is affected by amblyopia.

3D perception
Depth perception results from many monocular and binocular visual clues. For objects relatively close to the eyes, binocular vision plays an important role in depth perception. Binocular vision allows the brain to create a single Cyclopean image and to attach a depth level to each point in it.

The brain uses coordinate shift (also known as parallax) of matched objects to identify depth of these objects. The depth level of each point in the combined image can be represented by a grayscale pixel on a 2D image, for the benefit of the reader. The closer a point appears to the brain, the brighter it is painted. Thus, the way the brain perceives depth using binocular vision can be captured by a depth map (Cyclopean image) painted based on coordinate shift.

The eye operates like a photographic camera. It has an adjustable iris which can open (or close) to allow more (or less) light to enter the eye. As with any camera except pinhole cameras, it needs to focus light rays entering through the iris (aperture in a camera) so that they focus on a single point on the retina in order to produce a sharp image. The eye achieves this goal by adjusting a lens behind the cornea to refract light appropriately.

When a person stares at an object, the two eyeballs rotate sideways to point to the object, so that the object appears at the center of the image formed on each eye's retina. In order to look at a nearby object, the two eyeballs rotate towards each other so that their eyesight can converge on the object. This is referred to as cross-eyed viewing. To see a faraway object, the two eyeballs diverge to become almost parallel to each other. This is known as wall-eyed viewing, where the convergence angle is much smaller than that in cross-eyed viewing.

Stereo-vision based on parallax allows the brain to calculate depths of objects relative to the point of convergence. It is the convergence angle that gives the brain the absolute reference depth value for the point of convergence from which absolute depths of all other objects can be inferred.

Simulated 3D perception

The eyes normally focus and converge at the same distance in a process known as accommodative convergence. That is, when looking at a faraway object, the brain automatically flattens the lenses and rotates the two eyeballs for wall-eyed viewing. It is possible to train the brain to decouple these two operations. This decoupling has no useful purpose in everyday life, because it prevents the brain from interpreting objects in a coherent manner. To see a human-made picture such as an autostereogram where patterns are repeated horizontally, however, decoupling of focusing from convergence is crucial.

By focusing the lenses on a nearby autostereogram where patterns are repeated and by converging the eyeballs at a distant point behind the autostereogram image, one can trick the brain into seeing 3D images. If the patterns received by the two eyes are similar enough, the brain will consider these two patterns a match and treat them as coming from the same imaginary object. This type of visualization is known as wall-eyed viewing, because the eyeballs adopt a wall-eyed convergence on a distant plane, even though the autostereogram image is actually closer to the eyes. Because the two eyeballs converge on a plane farther away, the perceived location of the imaginary object is behind the autostereogram. The imaginary object also appears bigger than the patterns on the autostereogram because of foreshortening.

The following autostereogram shows three rows of repeated patterns. Each pattern is repeated at a different interval to place it on a different depth plane. The two non-repeating lines can be used to verify correct wall-eyed viewing. When the autostereogram is correctly interpreted by the brain using wall-eyed viewing, and one stares at the dolphin in the middle of the visual field, the brain should see two sets of flickering lines, as a result of binocular rivalry.

While there are six dolphin patterns in the autostereogram, the brain should see seven "apparent" dolphins on the plane of the autostereogram. This is a side effect of the pairing of similar patterns by the brain. There are five pairs of dolphin patterns in this image. This allows the brain to create five apparent dolphins. The leftmost pattern and the rightmost pattern by themselves have no partner, but the brain tries to assimilate these two patterns onto the established depth plane of adjacent dolphins despite binocular rivalry. As a result, there are seven apparent dolphins, with the leftmost and the rightmost ones appearing with a slight flicker, not dissimilar to the two sets of flickering lines observed when one stares at the 4th apparent dolphin.

Because of foreshortening, the difference in convergence needed to see repeated patterns on different planes causes the brain to attribute different sizes to patterns with identical 2D sizes. In the autostereogram of three rows of cubes, while all cubes have the same physical 2D dimensions, the ones on the top row appear bigger, because they are perceived as farther away than the cubes on the second and third rows.

Viewing techniques

If one has two eyes, fairly healthy eyesight, and no neurological conditions which prevent the perception of depth, then one is capable of learning to see the images within autostereograms. "Like learning to ride a bicycle or to swim, some pick it up immediately, while others have a harder time."

As with a photographic camera, it is easier to make the eye focus on an object when there is intense ambient light. With intense lighting, the eye can constrict the pupil, yet allow enough light to reach the retina. The more the eye resembles a pinhole camera, the less it depends on focusing through the lens. In other words, the degree of decoupling between focusing and convergence needed to visualize an autostereogram is reduced. This places less strain on the brain. Therefore, it may be easier for first-time autostereogram viewers to "see" their first 3D images if they attempt this feat with bright lighting.

Vergence control is important in being able to see 3D images. Thus it may help to concentrate on converging/diverging the two eyes to shift images that reach the two eyes, instead of trying to see a clear, focused image. Although the lens adjusts reflexively in order to produce clear, focused images, voluntary control over this process is possible. The viewer alternates instead between converging and diverging the two eyes, in the process seeing "double images" typically seen when one is drunk or otherwise intoxicated. Eventually the brain will successfully match a pair of patterns reported by the two eyes and lock onto this particular degree of convergence. The brain will also adjust eye lenses to get a clear image of the matched pair. Once this is done, the images around the matched patterns quickly become clear as the brain matches additional patterns using roughly the same degree of convergence.

When one moves one's attention from one depth plane to another (for instance, from the top row of the chessboard to the bottom row), the two eyes need to adjust their convergence to match the new repeating interval of patterns. If the level of change in convergence is too high during this shift, sometimes the brain can lose the hard-earned decoupling between focusing and convergence. For a first-time viewer, therefore, it may be easier to see the autostereogram, if the two eyes rehearse the convergence exercise on an autostereogram where the depth of patterns across a particular row remains constant.

In a random dot autostereogram, the 3D image is usually shown in the middle of the autostereogram against a background depth plane (see the shark autostereogram). It may help to establish proper convergence first by staring at either the top or the bottom of the autostereogram, where patterns are usually repeated at a constant interval. Once the brain locks onto the background depth plane, it has a reference convergence degree from which it can then match patterns at different depth levels in the middle of the image.

The majority of autostereograms, including those in this article, are designed for divergent (wall-eyed) viewing. One way to help the brain concentrate on divergence instead of focusing is to hold the picture in front of the face, with the nose touching the picture. With the picture so close to their eyes, most people cannot focus on the picture. The brain may give up trying to move eye muscles in order to get a clear picture. If one slowly pulls back the picture away from the face, while refraining from focusing or rotating eyes, at some point the brain will lock onto a pair of patterns when the distance between them matches the current convergence degree of the two eyeballs.

Another way is to stare at an object behind the picture in an attempt to establish proper divergence, while keeping part of the eyesight fixed on the picture to convince the brain to focus on the picture. A modified method has the viewer focus on their reflection on a reflective surface of the picture, which the brain perceives as being located twice as far away as the picture itself. This may help persuade the brain to adopt the required divergence while focusing on the nearby picture.

Those who wear eyeglasses with so-called "progressive" lenses, in which the focal length gradually changes so as to ease the viewing of close objects using the lower part of the lens, may find that viewing a stereogram is easier if the glasses are pushed up a little so that the stereogram is viewed through a part of the lens optimized for images that are closer than the actual distance to the stereogram.  When the eyes are made divergent by looking (or pretending to look) at a far-away object, the overcorrection from viewing the stereogram through the "wrong" part of the lens can bring the stereogram into focus without needing to overcome the tendency to focus on the far-away object while attempting to focus on the stereogram.

For crossed-eyed autostereograms, a different approach needs to be taken. The viewer may hold one finger between their eyes and move it slowly towards the picture, maintaining focus on the finger at all times, until they are correctly focused on the spot that will allow them to view the illusion.

Stereoblindness, however, is not known to permit the usages of any of these techniques, especially for persons in whom it may be, or is, permanent.

Terminology
Stereogram and autostereogram
Stereogram was originally used to describe as a pair of 2D images used in stereoscope to present a 3D image to viewers. The "auto" in autostereogram describes an image that does not require a stereoscope. The term stereogram is now often used interchangeably with autostereogram. Dr. Christopher Tyler, inventor of the autostereogram, consistently refers to single image stereograms as autostereograms to distinguish them from other forms of stereograms.
Random dot stereogram (RDS)
Random dot stereogram, describes a pair of 2D images containing random dots which, when viewed with a stereoscope, produced a 3D image. The term is now often used interchangeably with random dot autostereogram.
Single image stereogram (SIS)
Single image stereogram (SIS). SIS differs from earlier stereograms in its use of a single 2D image instead of a stereo pair and is viewed without a device. Thus, the term is often used as a synonym of autostereogram. When the single 2D image is viewed with proper eye convergence, it causes the brain to fuse different patterns perceived by the two eyes into a virtual 3D image without, hidden within the 2D image, the aid of any optical equipment. SIS images are created using a repeating pattern. Programs for their creation include Mathematica.
Random dot autostereogram/hidden image stereogram
Is also known as single image random dot stereogram (SIRDS). This term also refers to autostereograms where the hidden 3D image is created using a random pattern of dots within one image, shaped by a depth map within a dedicated stereogram rendering program.
Wallpaper autostereogram/object array stereogram/texture offset stereogram
Wallpaper autostereogram is a single 2D image where recognizable patterns are repeated at various intervals to raise or lower each pattern's perceived 3D location in relation to the display surface. Despite the repetition, these are a type of single image autostereogram.
Single image random text stereogram (SIRTS)
A single image random text ASCII stereogram is an alternative to SIRDS using random ASCII text instead of dots to produce a 3D form of ASCII art.
Map textured stereogram
In a map textured stereogram, "a fitted texture is mapped onto the depth image and repeated a number of times" resulting in a pattern where the resulting 3D image is often partially or fully visible before viewing.

See also
Diplopia
Lenticular printing
Vergence-Accommodation Conflict

Notes

References

Bibliography
N. E. Thing Enterprises (1993). Magic Eye: A New Way of Looking at the World. Kansas City: Andrews and McMeel.
Tyler, C.W. and Clarke, M.B. (1990) "The Autostereogram". Stereoscopic Displays and Applications, Proc. SPIE Vol. 1258:182–196.
Marr, D. and Poggio, T. (1976). "Cooperative computation of stereo disparity". Science, 194:283–287; October 15.
Julesz, B. (1964). "Binocular depth perception without familiarity cues". Science, 145:356–363.
Julesz, B. (1963). "Stereopsis and binocular 3d Stereogram rivalry of contours". Journal of the Optical Society of America, 53:994–999.
Julesz, B. and J.E. Miller. (1962). "Automatic stereoscopic presentation of functions of two variables". Bell System Technical Journal, 41:663–676; March.
Scott B. Steinman, Barbara A. Steinman and Ralph Philip Garzia. (2000). Foundations of Binocular Vision: A Clinical perspective. McGraw-Hill Medical.
Ron Kimmel. (2002) 3D Shape Reconstruction from Autostereograms and Stereo. Journal of Visual Communication and Image Representation, 13:324–333.

External links

Scholarpedia article on autostereograms Peer-reviewed article on autostereograms by Christopher Tyler
Stereograma - A Free Open-Source Cross-Platform Stereogram Generator
Autostereograms - 3D Magic eye, SIRDS - Gallery Images
Online ASCII stereogram generator

3D imaging
Optical illusions
Stereoscopy

Autostereogram


Women at War ist ein US-amerikanischer Kurzfilm aus dem Jahr 1943, der von Warner Bros. in Zusammenarbeit mit der US Army produziert wurde. Regie führte Jean Negulesco.

Handlung
Drei junge Frauen wollen im Women's Army Corps der US Army dienen und treffen in Fort Des Moines ein. Die Kriegswitwe Mary Sawyer will Offizier werden. Anastasia Hart, die auf einer Farm lebte, interessiert sich für den Transportdienst. Lorna Travis will die Anerkennung ihres Vaters, des chauvinistischen Major General Travis, gewinnen.

Nach intensivem Training unter der Führung von Major General Travis können die drei Frauen ihren Beitrag für die Kriegsanstrengungen der USA beisteuern und den Wert des Women's Army Corps bestätigen.

Veröffentlichung
Die Premiere fand am 2. Oktober 1943 statt.

Auszeichnung
Gordon Hollingshead wurde 1944 mit dem Film für den Oscar in der Kategorie "Bester Kurzfilm" (2 Filmrollen) nominiert.

Weblinks

Filmtitel 1943
US-amerikanischer Film
Kurzfilm
Propagandafilm (Zweiter Weltkrieg)

Women at War


Belen, Zonguldak ilinin Karadeniz Ereğli ilçesine bağlı bir köydür.

Tarihçe
Ereğliömerli köyünün Belen adında bir mahallesiyken, bu köy teşkilatının 29 Haziran 1957'de kaldırılmasıyla yine aynı köyün Kabakcılar mahallesiyle birleşerek Belen adıyla müstakil bir köy olmuştur.

Coğrafya
Zonguldak iline 45 km, Ereğli ilçesine 8 km uzaklıktadır.

Nüfus

Dış bağlantılar

Belen, Ereğli


ريكاردو لويز بوزي رودريغيز، الشهير باسم ريكاردينيو، (؛ مواليد 23 مايو 1976 في ساو باولو) هو لاعب كرة قدم برازيلي يلعب حالياً لنادي أتلتيكو مينيرو البرازيلي في خط الوسط.

لعب ريكاردينهو في أندية بارانا (1995-1997) بوردو (1997-1998) كورينثيانز (1998-2002) ساو باولو (2002-2004) مدلزبره (2004) سانتوس (2004-2005) كورينثيانز مجددا (2006) بشيكطاس (2006-2008) .

ساهم ريكاردينهو في تتويج نادي بارانا ببطولة ولاية باراناينزي 3 مرات 1995 ، 1996 ، و1997 كما ساهم في تتويج نادي كورينثيانز ببطولة دوري الدرجة الأولى مرتين 1998 و1999 وبطولة كأس العالم للأندية 2000 وبطولة كأس البرازيل 2002 وبطولة ولايتي ريو دي جانيرو وساو باولو 2002 وبطولة ولاية باوليستا مرتين 1999 و2001 كما ساهم في تتويج نادي سانتوس ببطولة دوري الدرجة الأولى 2004 كما ساهم في تتويج نادي بشيكطاس ببطولة كأس تركيا موسم 2006/2007 .

شارك ريكاردينهو مع منتخب البرازيل في 23 مباراة دولية مسجلا هدف واحد في الفترة من 2000 إلى 2006 . تم استدعائه للمشاركة في بطولة كأس العالم لكرة القدم 2002 التي أقيمت في كوريا الجنوبية واليابان معا . غاب عن المباراة الأولى أمام منتخب تركيا ثم شارك بديلا في المباراة الثانية أمام منتخب الصين التي انتهت بالفوز 4/0 ثم مجددا أيضا بديلا في المباراة الثالثة أمام منتخب كوستاريكا التي انتهت 5/2 . في الدور الثمن النهائي شارك بديلا أمام منتخب بلجيكا وانتهت بالفوز 2–0 ثم غاب حتى نهاية البطولة التي توج فيها منتخب البرازيل بطلاً.

روابط خارجية

مراجع

أشخاص على قيد الحياة
أشخاص من ساو باولو
برازيليون من أصل إيطالي
برازيليون من أصل برتغالي
رياضيون برازيليون مغتربون في إنجلترا
رياضيون برازيليون مغتربون في تركيا
رياضيون برازيليون مغتربون في فرنسا
رياضيون برازيليون مغتربون في قطر
لاعبو الدوري البرازيلي الدرجة الأولى
لاعبو الدوري التركي الممتاز
لاعبو الدوري الفرنسي
لاعبو المنتخبات الفائزة بكأس العالم
لاعبو أتليتيكو مينيرو
لاعبو بارانا
لاعبو بشكتاش
لاعبو بوردو
لاعبو دوري نجوم قطر
لاعبو سانتوس
لاعبو ساو باولو
لاعبو كأس العالم 2002
لاعبو كأس العالم 2006
لاعبو كأس القارات 2003
لاعبو كرة القدم البرازيليون
لاعبو كرة قدم برازيليون
لاعبو كرة قدم رجالية برازيليون مغتربون
لاعبو كرة قدم رجالية مغتربون في إنجلترا
لاعبو كرة قدم رجالية مغتربون في تركيا
لاعبو كرة قدم رجالية مغتربون في فرنسا
لاعبو كرة قدم رجالية مغتربون في قطر
لاعبو كرة قدم مغتربون برازيليون
لاعبو كرة قدم مغتربون في إنجلترا
لاعبو كرة قدم مغتربون في تركيا
لاعبو كرة قدم مغتربون في فرنسا
لاعبو كرة قدم مغتربون في قطر
لاعبو كرة قدم من ساو باولو
لاعبو منتخب البرازيل لكرة القدم
لاعبو ميدلزبره
لاعبو نادي الريان
لاعبو نادي باهيا
لاعبو نادي كورينثيانز
لاعبو وسط كرة قدم رجالية
مدربو الدوري البرازيلي الدرجة الثانية
مدربو جمعية بورتوغيزا الرياضية
مدربو كرة قدم برازيليون
مدربو نادي أفاي
مدربو نادي بارانا
مواليد 1396 هـ
مواليد 1976
مواليد في ساو باولو

ريكاردينيو


Le monument d'Huseyn Djavid est un monument dédié au poète azerbaïdjanais Huseyn Djavid, situé à Bakou, dans un parc nommé en son honneur, situé sur l'avenue Huseyn Djavid.

Histoire
L'inauguration du complexe commémoratif a eu lieu le 27 mai 1993. Les auteurs du monument sont le sculpteur Omar Eldarov, l'artiste du peuple d'Azerbaïdjan, et les architectes Yusif Gadimov et Rasim Aliyev.

Voir aussi

Notes et références

Culture à Bakou

Monument d'Huseyn Djavid