
#REDIRECT X-ray
:''In the NATO phonetic alphabet, X-ray represents the letter X.'' Wilhelm_Röntgen">Image:Roentgen-x-ray-von-kollikers-hand.jpg|thumb|right|An X-ray picture (radiograph) taken by Wilhelm Röntgen An X-ray or Röntgen ray is a form of electromagnetic radiation with a wavelength in the range of 10 1 E-9 m to 100 1 E-12 m (corresponding to frequencies in the range 30 SI prefix to 3 SI prefix). X-rays are primarily used for diagnostic medical imaging and X-ray crystallography. X-rays are a form of ionizing radiation and as such can be dangerous. ==Physics== X-rays with a wavelength approximately longer than 0.1 nm are called ''soft X-rays''. At wavelengths shorter than this, they are called hard X-rays. Hard X-rays overlap the range of "long"-wavelength (lower energy) gamma rays, however the distinction between the two terms depends on the source of the radiation, not its wavelength: X-ray photons are generated by energetic electron processes, gamma rays by transitions within atomic nucleus. The basic production of X-rays is by accelerating electrons in order to collide with a metal target (tungsten usually). Here the electrons suddenly decelerate upon colliding with the metal target and if enough energy is contained within the electron it is able to knock out an electron from the inner shell of the metal atom and as a result electrons from higher energy levels then fill up the vacancy and X-ray photons are emitted. ==Detectors== The detection of X-rays is based on various methods. The most commonly known method is the photographic plate, frequently used in hospitals. When a photographic negative plate is exposed to the X-rays, it turns white where the X-rays go through "soft" parts of the body like organs and skin, and black where the X-rays are stopped by "hard" parts like bone, or contrast product containing barium or iodine injected in blood. Another method is to use a fluorescent plate, e.g. sodium iodide NaI. These methods give no information about the energy of the X-ray photons, just their spatial density. Initially, most common detection methods were based on the ionisation of gases, as in the Geiger counter: a sealed cylinder with a polymer window contains a gas, and a wire, and a high voltage is applied between the cylinder (cathode) and the wire (anode). When an X-ray photon enters the cylinder, it ionises the gas which becomes conducting, creating a current flow (a kind of flash); this peak of current is detected and is called a "count". When the high voltage between anode and cathode is decreased, the detector is no longer saturated, and the height of the current peak is proportional to the energy of the photon; it is thus called a "proportional counter". Most of times, the cylinder is not sealed but is constantly fed with "fresh gas", is thus called a "flow counter". This proportionality property allows filtering the "interesting" peaks from the noise and other photons, but the resolution in energy is not enough to determine the energy spectrum; such a feature requires a diffraction crystal to first separate the different photons, the method is called wavelength dispersive X-ray spectroscopy (WDX or WDS). Some materials such as NaI can "convert" an X photon to a visible photon; an electronic detector can be built by adding a photomultiplier. These detectors are called "scintillator" or "scintillation counter". Since the 1970s, new semiconductor diode detectors have been developed (silicon or germanium doped with lithium, Si(Li) or Ge(Li)). X-ray photons are converted to electron-hole pairs in the semiconductor, and are collected to detect the X-rays. When the temperature is low enough (the detector is cooled by Peltier effect or best by liquid nitrogen), it is possible to directly determine the X-ray energy spectrum; this method is called energy dispersive X-ray spectroscopy (EDX or EDS); it is often used in small X-ray fluorescence spectrometers. These detectors are often called "solid detectors". It is commonly thought that X-rays are invisible to the human eye, and for almost all everyday uses of X-rays this may seem true, however, very strictly speaking, it is actually false. In special circumstances, X-rays are in fact visible to the "naked eye". An effect first discovered by Brandes in experimentation a short time after Wilhelm Röntgen landmark 1895 paper; he reported, after dark adaptation and placing his eye close to an X-ray tube, seeing a faint "blue-gray" glow which seemed to originate within the eye itself.[http://www.orau.org/ptp/articlesstories/invisiblelight.htm] Upon hearing this, Röntgen reviewed his record books and found he in fact, also saw the effect. When placing an X-ray tube on the opposite side of a wooden door Röntgen saw the same blue glow seeming to emanate from the eye itself, but thought his observations were spurious due to the fact that he only saw the effect when he used one type of tube. Later he realized that the tube which created the effect was the only one which produced X-rays powerful enough to make the glow plainly visible and the experiment was thereafter repeated readily. The fact that X-rays are actually faintly visible to the dark-adapted naked eye has largely been forgotten today is probably due to the lack of desire to repeat what we would now see as a recklessly dangerous and harmful experiment with ionizing radiation. It is not known what the exact mechanism in the eye is which produces the visibility and it could be due to either conventional detection (excitation of rhodopsin molecules in the retina), direct excitation of retinal nerve cells, or secondary detection via, for instance, X-ray induction of phosphorescence in the eyeball and then conventional retinal detection of the secondarily produced visible light. ==Medical uses== [[Image:Dental x-ray.jpg|right|thumb|222px||X-rays can reveal the details of bones and teeth]] Since Röntgen's discovery that X-rays can identify bony structures, X-rays have been developed for their use in medical imaging. Radiology is a specialised field of medicine that employs radiography and other techniques for diagnostic imaging. Indeed, this is probably the most common use of X-ray technology. The use of X-rays are especially useful in the detection of pathology of the bone, but are also useful for detecting some disease processes in soft tissue. Some notable examples are the very common chest X-ray, which can be used to identify lung diseases such as pneumonia, lung cancer or pulmonary oedema, and the abdominal X-ray, which can detect ileus (blockage of the intestine), free air (from visceral perforations) and free fluid (in ascites). In some cases, the use of X-rays is debatable, such as gallstones (which are rarely radiopaque) or kidney stones (which are often visible, but not always). Also, Traditional plain X-rays pose very little use in the imaging of soft tissues such as the brain or muscle. Imaging alternatives for soft tissues are computed axial tomography (CAT or CT scanning), magnetic resonance imaging (MRI) or medical ultrasonography. X-rays are also used in "real-time" procedures such as angiography or contrast studies of the hollow organs (e.g. barium enema of the small or large intestine) using fluoroscopy. Angioplasty, medical interventions of the arterial system, rely heavily on X-ray-sensitive contrast to identify potentially treatable lesions. Radiotherapy, a curative medical intervention, now used almost exclusively for cancer, employs higher energies of radiation. ==History== Among the important early researchers in X-rays were Professor Ivan Pului, Sir William Crookes, Johann Wilhelm Hittorf, Eugene Goldstein, Heinrich Hertz, Philipp Lenard, Hermann von Helmholtz, Nikola Tesla, Thomas Edison, Charles Glover Barkla, Max von Laue, and Wilhelm Conrad Röntgen. Physicist Johann Hittorf (1824 - 1914) observed vacuum tube with energy rays extending from a negative electrode. These rays produced a fluorescence when they hit the glass walls of the tubes. In 1876 the effect was named "Cathode ray" by Eugene Goldstein. Later, English physicist William Crookes investigated the effects of energy discharges on rare gases, and constructed what is called the Crookes tube. It is a glass vacuum cylinder, containing electrodes for discharges of a high voltage electric current. He found, when he placed unexposed photographic plates near the tube, that some of them were flawed by shadows, though he did not investigate this effect. In April 1887, Nikola Tesla began to investigate X-rays using high voltages and vacuum tubes of his own design, as well as Crookes tubes. From his technical publications, it is indicated that he invented and developed a special single-electrode X-ray tube, which differed from other X-ray tubes in having no target electrode. He stated these facts in his 1897 X-ray lecture before the New York Academy of Sciences. The principle behind Tesla's device is nowadays called the bremsstrahlung process, in which a high-energy secondary X-ray emission is produced when charged particles (such as electrons) pass through matter. By 1892, Tesla performed several such experiments, but he did not categorize the emissions as what were later called X-rays, instead generalizing the phenomenon as radiant energy. He did not publicly declare his findings nor did he make them widely known. His subsequent X-ray experimentation by vacuum high field emissions led him to alert the scientific community to the biological hazards associated with X-ray exposure. In 1892, Heinrich Hertz began experimenting and demonstrated that cathode rays could penetrate very thin metal foil (such as aluminium). Philipp Lenard, a student of Heinrich Hertz, further researched this effect. He developed a version of the cathode tube and studied the penetration by X-rays of various materials. Philipp Lenard, though, did not realize that he was producing X-rays. Hermann von Helmholtz formulated mathematical equations for X-rays. He postulated a dispersion theory before Röntgen made his discovery and announcement. It was formed on the basis of the electromagnetic theory of light (''Wiedmann's Annalen'', Vol. XLVIII). However, he did not work with actual X-rays. On November 8 1895, Wilhelm Röntgen, a Germany scientist, began observing and further documenting X-rays while experimenting with vacuum tubes. Röntgen, on December 28, 1895, wrote a preliminary report "''On a new kind of ray: A preliminary communication''". He submitted it to the Würzburg's Physical-Medical Society journal. This was the first formal and public recognition of the categorization of X-rays. Röntgen referred to the radiation as "X", to indicate that it was an unknown type of radiation. The name stuck, although (over Röntgen's great objections), many of his colleagues suggested calling them Röntgen rays. They are still referred to as such in many languages, see "in other languages" in the left margin of this article. Röntgen received the first Nobel Prize in Physics for his discovery. In 1895, Thomas Edison investigated materials' ability to fluoresce when exposed to X-rays, and found that calcium tungstate was the most effective substance. Around March 1896, the fluoroscope he developed became the standard for medical X-ray examinations. Nevertheless, Edison dropped X-ray research around 1903 after the death of Clarence Madison Dally, one of his glassblowers. Dally had a habit of testing X-ray tubes on his hands, and acquired a cancer in them so tenacious that both arms were amputation in a futile attempt to save his life[http://www.ratical.org/radiation/KillingOurOwn/KOO6.html]. In 1906, physicist Charles Glover Barkla discovered that X-rays could be scattered by gases, and that each element had a characteristic X-ray. He won the 1917 Nobel Prize in Physics for this discovery. The use of X-rays for medical purposes (to develop into the field of radiation therapy) was pioneered by Major John Hall-Edwards in Birmingham, England. In 1908, he had to have his left arm amputated owing to the spread of X-ray dermatitis[http://www.birmingham.gov.uk/xray]. In the 1950s X-rays were first harnessed to produce an X-ray microscope. [[Image:Moon in x-rays.gif|thumb|right|222px|ROSAT image of X-ray fluorescence of, and occultation of the X-ray background by, the Moon.]] In the 1980s an X-ray laser device was proposed as part of the Ronald Reagan administration's Strategic Defense Initiative, but the first and only test of the device (a sort of laser "blaster", or death ray, powered by a thermonuclear explosion) gave inconclusive results. For technical and political reasons, the overall project (including the X-ray laser) was de-funded (though was later revived by the second George W. Bush administration as National Missile Defense using different technologies). In the 1990s the [http://chandra.harvard.edu/ Chandra X-Ray Observatory] was launched, allowing the exploration of the very violent processes in the universe which produce X-Rays. Unlike visible light, which is a relatively stable view of the universe, the x-ray universe is unstable, it features stars being torn apart by black holes, galactic collisions, and novas, neutron stars that build up layers of plasma that then explode into space. ==See also== * X-ray crystallography * X-ray astronomy * X-ray machine * X-ray microscopy * Geiger counter * N ray X-rays Medical imaging ms:Sinar-X
The third line on the physics paragraph refers to gamma rays as "low energy" when they are instead the highest energy region of the spectrum. I just wanted to bring up this point and let someone with better writing skills modify that paragraph. A previous entry claimed to quote from Tesla's speech and gave him precedence in discovering x-rays. The actual speech found online says: "The taking of these photographic impressions by means of Crooks bulbs brought freshly to my mind the experiments of Lenard, some features of which, particularly the action on a sensitive plate..." "...which made me temporarily forget my projects. I had hardly finished the work of reconstruction and resumed the course of my ideas when the news of Roentgen's achievement reached me. Instantly the truth flashed upon my mind. I hurried to repeat his incompletely reported experiments, and there I beheld the wonder myself. Then — too late — I realized that my guiding spirit had again prompted me and that I had failed to comprehend his mysterious signs. . . .But while I have failed to see what others in my place might have perceived..." So he first claims that Lenard did it before him and then admits he didn't understand it. User:Rmhermen 04:59, 4 Aug 2003 (UTC) ---- Some quotes on Tesla's priority over Roentgen ...
See other meanings of words starting from letter:
Words begining with X-ray:
X-Ray
X-ray
X-ray
X-rays
X-rays
X-ray_(chess)
X-ray_(chess)
X-ray_absorption_fine_structure
X-Ray_astronomy
X-ray_Astronomy
X-ray_astronomy
X-ray_background
X-ray_binaries
X-ray_binary
X-ray_burster
X-Ray_Crystallography
X-ray_crystallography
X-ray_crystallography
X-ray_diffraction
X-Ray_Diffraction_Pattern
X-Ray_engine
X-Ray_fluorescence
X-ray_fluorescence
X-ray_fluorescence_spectroscopy
X-ray_Glasses
X-ray_glasses
X-ray_machine
X-ray_machine
X-Ray_Microscope
X-ray_microscope
X-ray_microscopy
X-ray_photoelectron_spectroscopy
X-ray_pulsar
X-ray_scattering
X-Ray_Scope
X-Ray_Sierra
X-Ray_Sierra
X-Ray_Source
X-Ray_Specs
X-ray_spectroscopy
X-Ray_Spectrum
X-Ray_Spex
X-Ray_Spex
X-ray_Spex
X-ray_structure
X-Ray_Style
X-Ray_Telescope
X-ray_telescopes
X-Ray_treatment
X-Ray_Tube
X-Ray_tube
X-ray_tube
X-ray_vision
X-Ray_Visor
X-Ray
#REDIRECT X-ray
X-ray
:''In the NATO phonetic alphabet, X-ray represents the letter X.'' Wilhelm_Röntgen">Image:Roentgen-x-ray-von-kollikers-hand.jpg|thumb|right|An X-ray picture (radiograph) taken by Wilhelm Röntgen An X-ray or Röntgen ray is a form of electromagnetic radiation with a wavelength in the range of 10 1 E-9 m to 100 1 E-12 m (corresponding to frequencies in the range 30 SI prefix to 3 SI prefix). X-rays are primarily used for diagnostic medical imaging and X-ray crystallography. X-rays are a form of ionizing radiation and as such can be dangerous. ==Physics== X-rays with a wavelength approximately longer than 0.1 nm are called ''soft X-rays''. At wavelengths shorter than this, they are called hard X-rays. Hard X-rays overlap the range of "long"-wavelength (lower energy) gamma rays, however the distinction between the two terms depends on the source of the radiation, not its wavelength: X-ray photons are generated by energetic electron processes, gamma rays by transitions within atomic nucleus. The basic production of X-rays is by accelerating electrons in order to collide with a metal target (tungsten usually). Here the electrons suddenly decelerate upon colliding with the metal target and if enough energy is contained within the electron it is able to knock out an electron from the inner shell of the metal atom and as a result electrons from higher energy levels then fill up the vacancy and X-ray photons are emitted. ==Detectors== The detection of X-rays is based on various methods. The most commonly known method is the photographic plate, frequently used in hospitals. When a photographic negative plate is exposed to the X-rays, it turns white where the X-rays go through "soft" parts of the body like organs and skin, and black where the X-rays are stopped by "hard" parts like bone, or contrast product containing barium or iodine injected in blood. Another method is to use a fluorescent plate, e.g. sodium iodide NaI. These methods give no information about the energy of the X-ray photons, just their spatial density. Initially, most common detection methods were based on the ionisation of gases, as in the Geiger counter: a sealed cylinder with a polymer window contains a gas, and a wire, and a high voltage is applied between the cylinder (cathode) and the wire (anode). When an X-ray photon enters the cylinder, it ionises the gas which becomes conducting, creating a current flow (a kind of flash); this peak of current is detected and is called a "count". When the high voltage between anode and cathode is decreased, the detector is no longer saturated, and the height of the current peak is proportional to the energy of the photon; it is thus called a "proportional counter". Most of times, the cylinder is not sealed but is constantly fed with "fresh gas", is thus called a "flow counter". This proportionality property allows filtering the "interesting" peaks from the noise and other photons, but the resolution in energy is not enough to determine the energy spectrum; such a feature requires a diffraction crystal to first separate the different photons, the method is called wavelength dispersive X-ray spectroscopy (WDX or WDS). Some materials such as NaI can "convert" an X photon to a visible photon; an electronic detector can be built by adding a photomultiplier. These detectors are called "scintillator" or "scintillation counter". Since the 1970s, new semiconductor diode detectors have been developed (silicon or germanium doped with lithium, Si(Li) or Ge(Li)). X-ray photons are converted to electron-hole pairs in the semiconductor, and are collected to detect the X-rays. When the temperature is low enough (the detector is cooled by Peltier effect or best by liquid nitrogen), it is possible to directly determine the X-ray energy spectrum; this method is called energy dispersive X-ray spectroscopy (EDX or EDS); it is often used in small X-ray fluorescence spectrometers. These detectors are often called "solid detectors". It is commonly thought that X-rays are invisible to the human eye, and for almost all everyday uses of X-rays this may seem true, however, very strictly speaking, it is actually false. In special circumstances, X-rays are in fact visible to the "naked eye". An effect first discovered by Brandes in experimentation a short time after Wilhelm Röntgen landmark 1895 paper; he reported, after dark adaptation and placing his eye close to an X-ray tube, seeing a faint "blue-gray" glow which seemed to originate within the eye itself.[http://www.orau.org/ptp/articlesstories/invisiblelight.htm] Upon hearing this, Röntgen reviewed his record books and found he in fact, also saw the effect. When placing an X-ray tube on the opposite side of a wooden door Röntgen saw the same blue glow seeming to emanate from the eye itself, but thought his observations were spurious due to the fact that he only saw the effect when he used one type of tube. Later he realized that the tube which created the effect was the only one which produced X-rays powerful enough to make the glow plainly visible and the experiment was thereafter repeated readily. The fact that X-rays are actually faintly visible to the dark-adapted naked eye has largely been forgotten today is probably due to the lack of desire to repeat what we would now see as a recklessly dangerous and harmful experiment with ionizing radiation. It is not known what the exact mechanism in the eye is which produces the visibility and it could be due to either conventional detection (excitation of rhodopsin molecules in the retina), direct excitation of retinal nerve cells, or secondary detection via, for instance, X-ray induction of phosphorescence in the eyeball and then conventional retinal detection of the secondarily produced visible light. ==Medical uses== [[Image:Dental x-ray.jpg|right|thumb|222px||X-rays can reveal the details of bones and teeth]] Since Röntgen's discovery that X-rays can identify bony structures, X-rays have been developed for their use in medical imaging. Radiology is a specialised field of medicine that employs radiography and other techniques for diagnostic imaging. Indeed, this is probably the most common use of X-ray technology. The use of X-rays are especially useful in the detection of pathology of the bone, but are also useful for detecting some disease processes in soft tissue. Some notable examples are the very common chest X-ray, which can be used to identify lung diseases such as pneumonia, lung cancer or pulmonary oedema, and the abdominal X-ray, which can detect ileus (blockage of the intestine), free air (from visceral perforations) and free fluid (in ascites). In some cases, the use of X-rays is debatable, such as gallstones (which are rarely radiopaque) or kidney stones (which are often visible, but not always). Also, Traditional plain X-rays pose very little use in the imaging of soft tissues such as the brain or muscle. Imaging alternatives for soft tissues are computed axial tomography (CAT or CT scanning), magnetic resonance imaging (MRI) or medical ultrasonography. X-rays are also used in "real-time" procedures such as angiography or contrast studies of the hollow organs (e.g. barium enema of the small or large intestine) using fluoroscopy. Angioplasty, medical interventions of the arterial system, rely heavily on X-ray-sensitive contrast to identify potentially treatable lesions. Radiotherapy, a curative medical intervention, now used almost exclusively for cancer, employs higher energies of radiation. ==History== Among the important early researchers in X-rays were Professor Ivan Pului, Sir William Crookes, Johann Wilhelm Hittorf, Eugene Goldstein, Heinrich Hertz, Philipp Lenard, Hermann von Helmholtz, Nikola Tesla, Thomas Edison, Charles Glover Barkla, Max von Laue, and Wilhelm Conrad Röntgen. Physicist Johann Hittorf (1824 - 1914) observed vacuum tube with energy rays extending from a negative electrode. These rays produced a fluorescence when they hit the glass walls of the tubes. In 1876 the effect was named "Cathode ray" by Eugene Goldstein. Later, English physicist William Crookes investigated the effects of energy discharges on rare gases, and constructed what is called the Crookes tube. It is a glass vacuum cylinder, containing electrodes for discharges of a high voltage electric current. He found, when he placed unexposed photographic plates near the tube, that some of them were flawed by shadows, though he did not investigate this effect. In April 1887, Nikola Tesla began to investigate X-rays using high voltages and vacuum tubes of his own design, as well as Crookes tubes. From his technical publications, it is indicated that he invented and developed a special single-electrode X-ray tube, which differed from other X-ray tubes in having no target electrode. He stated these facts in his 1897 X-ray lecture before the New York Academy of Sciences. The principle behind Tesla's device is nowadays called the bremsstrahlung process, in which a high-energy secondary X-ray emission is produced when charged particles (such as electrons) pass through matter. By 1892, Tesla performed several such experiments, but he did not categorize the emissions as what were later called X-rays, instead generalizing the phenomenon as radiant energy. He did not publicly declare his findings nor did he make them widely known. His subsequent X-ray experimentation by vacuum high field emissions led him to alert the scientific community to the biological hazards associated with X-ray exposure. In 1892, Heinrich Hertz began experimenting and demonstrated that cathode rays could penetrate very thin metal foil (such as aluminium). Philipp Lenard, a student of Heinrich Hertz, further researched this effect. He developed a version of the cathode tube and studied the penetration by X-rays of various materials. Philipp Lenard, though, did not realize that he was producing X-rays. Hermann von Helmholtz formulated mathematical equations for X-rays. He postulated a dispersion theory before Röntgen made his discovery and announcement. It was formed on the basis of the electromagnetic theory of light (''Wiedmann's Annalen'', Vol. XLVIII). However, he did not work with actual X-rays. On November 8 1895, Wilhelm Röntgen, a Germany scientist, began observing and further documenting X-rays while experimenting with vacuum tubes. Röntgen, on December 28, 1895, wrote a preliminary report "''On a new kind of ray: A preliminary communication''". He submitted it to the Würzburg's Physical-Medical Society journal. This was the first formal and public recognition of the categorization of X-rays. Röntgen referred to the radiation as "X", to indicate that it was an unknown type of radiation. The name stuck, although (over Röntgen's great objections), many of his colleagues suggested calling them Röntgen rays. They are still referred to as such in many languages, see "in other languages" in the left margin of this article. Röntgen received the first Nobel Prize in Physics for his discovery. In 1895, Thomas Edison investigated materials' ability to fluoresce when exposed to X-rays, and found that calcium tungstate was the most effective substance. Around March 1896, the fluoroscope he developed became the standard for medical X-ray examinations. Nevertheless, Edison dropped X-ray research around 1903 after the death of Clarence Madison Dally, one of his glassblowers. Dally had a habit of testing X-ray tubes on his hands, and acquired a cancer in them so tenacious that both arms were amputation in a futile attempt to save his life[http://www.ratical.org/radiation/KillingOurOwn/KOO6.html]. In 1906, physicist Charles Glover Barkla discovered that X-rays could be scattered by gases, and that each element had a characteristic X-ray. He won the 1917 Nobel Prize in Physics for this discovery. The use of X-rays for medical purposes (to develop into the field of radiation therapy) was pioneered by Major John Hall-Edwards in Birmingham, England. In 1908, he had to have his left arm amputated owing to the spread of X-ray dermatitis[http://www.birmingham.gov.uk/xray]. In the 1950s X-rays were first harnessed to produce an X-ray microscope. [[Image:Moon in x-rays.gif|thumb|right|222px|ROSAT image of X-ray fluorescence of, and occultation of the X-ray background by, the Moon.]] In the 1980s an X-ray laser device was proposed as part of the Ronald Reagan administration's Strategic Defense Initiative, but the first and only test of the device (a sort of laser "blaster", or death ray, powered by a thermonuclear explosion) gave inconclusive results. For technical and political reasons, the overall project (including the X-ray laser) was de-funded (though was later revived by the second George W. Bush administration as National Missile Defense using different technologies). In the 1990s the [http://chandra.harvard.edu/ Chandra X-Ray Observatory] was launched, allowing the exploration of the very violent processes in the universe which produce X-Rays. Unlike visible light, which is a relatively stable view of the universe, the x-ray universe is unstable, it features stars being torn apart by black holes, galactic collisions, and novas, neutron stars that build up layers of plasma that then explode into space. ==See also== * X-ray crystallography * X-ray astronomy * X-ray machine * X-ray microscopy * Geiger counter * N ray X-rays Medical imaging ms:Sinar-X
_taken_by_<a_href=\){kind=link}
X-ray
The third line on the physics paragraph refers to gamma rays as "low energy" when they are instead the highest energy region of the spectrum. I just wanted to bring up this point and let someone with better writing skills modify that paragraph. A previous entry claimed to quote from Tesla's speech and gave him precedence in discovering x-rays. The actual speech found online says: "The taking of these photographic impressions by means of Crooks bulbs brought freshly to my mind the experiments of Lenard, some features of which, particularly the action on a sensitive plate..." "...which made me temporarily forget my projects. I had hardly finished the work of reconstruction and resumed the course of my ideas when the news of Roentgen's achievement reached me. Instantly the truth flashed upon my mind. I hurried to repeat his incompletely reported experiments, and there I beheld the wonder myself. Then — too late — I realized that my guiding spirit had again prompted me and that I had failed to comprehend his mysterious signs. . . .But while I have failed to see what others in my place might have perceived..." So he first claims that Lenard did it before him and then admits he didn't understand it. User:Rmhermen 04:59, 4 Aug 2003 (UTC) ---- Some quotes on Tesla's priority over Roentgen ...
1892 Tesla discovers x-ray radiation while experimenting with HV and evacuated tubes : http://205.243.100.155/frames/tesla.html
Tesla opened a new laboratory. By 1897, he had carried out investigations in the field of X-ray : http://members.aol.com/k3bu/tesla73.htm
In April 1887, he established his own laboratory, where he experimented with shadowgraphs similar to those involved in the discovery of x-rays : http://www.frank.germano.com/nikolatesla.htm
The ''Electrical Review'' in 1896 published X-rays of a man, made by Tesla, with X-ray tubes of his own design. They appeared at the same time as when Roentgen announced his discovery of X-rays. Tesla never attempted to proclaim priority. Roentgen congratulated Tesla on his sophisticated X-ray pictures, and Tesla even wrote Roentgen's name on one of his films. He experimented with shadowgraphs similar to those that later were to be used by Wilhelm Rontgen when he discovered X-rays in 1895. : http://www.teslasociety.com/biography.htm
After a difficult period, during which Tesla invented but lost his rights to an arc-lighting system, he established his own laboratory in New York City in 1887, where his inventive mind could be given free rein. He experimented with shadowgraphs similar to those that later were to be used by Wilhelm Röntgen when he discovered X-rays in 1895. : http://www.acmi.net.au/AIC/TESLA_BIO.htmlThere are plenty of other sources on tesla and his work on x-rays before Roentgen - User:Reddi 22:38, 4 Aug 2003 (UTC) :Yes he and several others worked on x-rays. However it was Roentgen who figured it out. He "discovered" it. User:Rmhermen 00:08, 5 Aug 2003 (UTC) ::Just some links ... :: He also took the first x-ray photographs. - http://www.pbs.org/tesla/ll/ll_hifreq.html :: The Electrical Review in 1896 published X-rays of a man, made by Tesla, with X-ray tubes of his own design. They appeared at the same time as when Roentgen announced his discovery of X-rays. - http://www.teslasociety.com/biography.htm :: Photos of Tesla's image and news articles - http://www.teslasociety.com/xray.gif :: Lecture. Tesla's independent discovery of X-Ray - http://www.tfcbooks.com/mall/more/351ntl.htm :: He experimented with shadowgraphs similar to those that later were to be used by Wilhelm Röntgen - http://chem.ch.huji.ac.il/~eugeniik/history/tesla.htm and http://www.qsl.net/dominiondx/tesla.htm ---- Tesla was not aware of certain characteristics of x-rays. X-rays were not discovered yet. He was just working on unknown effect of phosphorescent light and admits in the article we both quote that he did not understand it. Also you have presented no evidence that Tesla took any human photographs before Roentgen or that he ever sent any photograph to him, much less before the publication of Roentgen's work. Also "1896 in the Electrical Review" is after 1895 when Roentgen published. User:Rmhermen 13:32, Aug 7, 2003 (UTC) ---- Image please? Sure everyone's seen hospital x-rays, but it would still make this article cooler. ---- The discussion on cathode rays is pretty confusingly written and even seems to imply that cathode rays were X-rays. It needs writing clearly explaining that Cathode rays (which perhaps merit their own page) were originally thought to be rays and were only later found to be streams of electrons. High energy cathode rays can create X rays when they hit something. User:BozMoUser Talk:BozMo ----- Also anyone mind if I change the link under "10 nanometers" to the nanometers link? It seems far more likely people would follow it looking for a definition which they can only get to by following the nm link in the linked page? --User Talk:BozMoUser:BozMo 11:46, 13 May 2004 (UTC) ----- Are there no articles on X-ray optics; parabolic/hyperbolic kirkpatrick baez /wolter telescopes and the like on wikipedia? :o( --User:Deglr6328 03:01, 14 Aug 2004 (UTC) == Röntgen or Roentgen == In 2003, the German language was formally changed to use oe in preference to ö. This change hasn't yet eprcolated through society, and newspapers are still printing Schröder rather than Schroeder, but oe is being taught in schools in preference to ö. Since the wiki entry is Willhelm Röntgen, and the majority of the references in the article were Röntgen, I have changed oe to ö in this article. However, I believe that considering that the official norm in German is now to prefer oe to ö, the wiki should move over to the English spelling of German names. This is, after all, an English wiki, and ö is not an English character. User:PhilHibbs 13:45, 26 Aug 2004 (UTC) "In 2003, the German language was formally changed to use oe in preference to ö." Never heard of that and indeed it doesn't look like it's being followed. Liked to read about it. The ministers of education, who decide what's taught in schools, continue to use it. http://www.kmk.org/index1.shtml "This is, after all, an English wiki, and ö is not an English character." The characters are offered when editing, probably to encourage their use in names that have them. --User:217.230.123.70 10:47, 9 Feb 2005 (UTC) Hi! I am an Austrian user, and nobody (in Austria, Germany or Switzerland) is using oe instead of ö - except for describing those "Umlaut"s in other language. Since you guys don't have an "ö" on your keyboard, I believe it's ok to use "oe" instead in the title. In the article, though, i would stick with the correct german version... -- User:Mnolf 07:40, 9 Jun 2005 (UTC) == Visible x-rays? == In my opinion, the 'visible' x-rays represent phosphorescence of structures within the eye-ball, rather than truly visible x-rays. I have requested peer review. User:Axl 14:53, 23 Nov 2004 (UTC) *If I recall correctly I'm the one who added the majority of the information on X-rays being visible. I am confident that the information I provided in the paragraph at the end of the "Detectors" section is factually and historically accurate (see here:[http://www.orau.org/ptp/articlesstories/invisiblelight.htm]) however, I share your uncertainty about the actual mechanism which makes them visible. The question being, are the X-rays inducing phosphorescence in the retina or aqueous humor itself or are the X-rays directly exciting neurons in the retina OR are they exciting (and destroying?) rhodopsin molecules in the retina conventionally and causing visual signals to be sent? I would guess that because no one is going to be repeating these crazy experiments with X-ray beams on thier eyeballs anytime soon we probably have no real way of knowing for sure so we might just add a mention of this controversy on in the article. X-rays are indeed visible, but HOW and what is our definition of "visible"?--User:Deglr6328 22:20, 23 Nov 2004 (UTC) *Okay, that's a sensible solution. User:Axl 11:51, 24 Nov 2004 (UTC) == bragg == how about mentioning all the x-ray stuff the braggs http://en.wikipedia.org/wiki/William_Henry_Bragg did on crystals. --ssam ==Propose move to "X-rays"== The article is currently under the name "X-ray", I would like to propose it be moved to "X-rays" instead. The term "X-ray" most often refers to the image taken of an object using X-rays. Thoughts?--User:Deglr6328 02:06, 6 Feb 2005 (UTC) :No - first, given that X-ray photographs (i.e. X-rays) are taken using X-rays, I can't see why the page title needs to change. But anyway, pages are generally listed in the singular, unless the plural is the predominant usage. -- User:ALoan User_talk:ALoan 23:01, 6 Feb 2005 (UTC) ::Right, this is why I think it should be moved. The article is firstly about the portion of the electromagnetic spectrum not the medical imaging technique and the term "X-rays" is the plural, predominant usage. Just like Gamma rays, cosmic rays etc.--User:Deglr6328 00:22, 7 Feb 2005 (UTC) :::But gamma ray, cosmic ray are both at the singular. There is already a separate article on radiography. -- User:ALoan User_talk:ALoan 12:30, 7 Feb 2005 (UTC) == Medical Affects/Early History == Does anyone have better information about the adverse health affects of x-rays, especially during the early evolution of the technology? Several scientists have developed x-ray burns or cancer, sometimes leading to death. Also, according to the History Channel, some scientists early on believed that they could use x-rays to change the skin tone of black people. In short, I think there could be better information about the early experimentation associated with the technology. User:Tkessler 00:33, Feb 18, 2005 (UTC)
See other meanings of words starting from letter:
X
Words begining with X-ray:
X-Ray
X-ray
X-ray
X-rays
X-rays
X-ray_(chess)
X-ray_(chess)
X-ray_absorption_fine_structure
X-Ray_astronomy
X-ray_Astronomy
X-ray_astronomy
X-ray_background
X-ray_binaries
X-ray_binary
X-ray_burster
X-Ray_Crystallography
X-ray_crystallography
X-ray_crystallography
X-ray_diffraction
X-Ray_Diffraction_Pattern
X-Ray_engine
X-Ray_fluorescence
X-ray_fluorescence
X-ray_fluorescence_spectroscopy
X-ray_Glasses
X-ray_glasses
X-ray_machine
X-ray_machine
X-Ray_Microscope
X-ray_microscope
X-ray_microscopy
X-ray_photoelectron_spectroscopy
X-ray_pulsar
X-ray_scattering
X-Ray_Scope
X-Ray_Sierra
X-Ray_Sierra
X-Ray_Source
X-Ray_Specs
X-ray_spectroscopy
X-Ray_Spectrum
X-Ray_Spex
X-Ray_Spex
X-ray_Spex
X-ray_structure
X-Ray_Style
X-Ray_Telescope
X-ray_telescopes
X-Ray_treatment
X-Ray_Tube
X-Ray_tube
X-ray_tube
X-ray_vision
X-Ray_Visor
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