Talk:Kálmán Tihanyi
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Plagiarism and other severe problems
editNearly this whole article is a mass of plagiarism. See Wikipedia:Plagiarism. Cheers, Rico402 (talk) 09:58, 29 January 2009 (UTC)
Tihanyi sounds like a brilliant mind, but this article is not only (as stated already) a mass of plagiarism, but a mess of OR, unsourced synthesis, reliance on self-published and web sources (including some by relatives of Tihanyi) and similar problems. I certainly hope someone is working on a full-scale biography of the man, because he absolutely deserves it. But until then, this article will have to be scaled back and stick to what's verifiable, even if that means many or most of the subject's achievements will be passed over. Those who really know the subject and are familiar with the documentary evidence available should start doing that now, before someone with less care just cuts and slashes to bring the article into line with Wikipedia standards. Sorry, but this is going to have to happen one way or the other, sooner or later. 64.119.152.82 (talk) 14:55, 22 December 2009 (UTC)
Responding to user talk: 64.119.152.82
editTake it from one who really knows the subject and is thoroughly familiar with the documentary evidence regarding all the major players: although this article can certainly use some correction everything it says about Kalman Tihanyi's achievments are veryfiable and richly documented. User talk. Hermes. 7 January 2010 —Preceding unsigned comment added by 193.6.201.128 (talk) 18:47, 7 January 2010 (UTC)
Reference 22
editThe English translation of the Hungarian title of Reference 22, K. Tihanyi: "Az elektromos távolbavetítésről" ("About electric transmission"), is wrong. The literal translation of the title is "On electric remote projection". It would probably be reasonable to translate "remote projection" as "television". Furthermore, it seems clear from the text where reference 22 is invoked that the sense in which "electric" is used would now be described as "electronic". So the correct translation of the title is either "On electric television" or "On electronic television". I corrected this, using the latter version. Mateat (talk) 22:41, 19 August 2009 (UTC)Willoughby_Smith
Farnsworth's US patent 2,087,683.
editCan someone comment about the similarities between the Tihayi's US patent 2,158,259[[1]] and Farnsworth's one number 2,087,683[[2]]?
At the end of the web page image dissector, in the improvements and external links sections, it is said that Farnsworth's US Patent 2,087,683 is a second generation image dissector invented in 1933, the first ever patent on a low velocity system precursor to iconoscope and image orthicon systems, but they do not give the deserved credit to Kalman Tihanyi.
Both devices from Tihanyi and Farnswroth uses a charge storage plate containing a mosaic of electrically isolated photosensitive granules separated from a common plate by a thin layer of isolating material (lines 8 to 20 in page 2 of Farnsworth's patent). The main difference lies in the fact that, in Tihanyi's apparatus, the electrons travel from the cathode to the charge storage plate and to the anode following a V-path (forming an angle); while in the Farnsworth's, device the electrons travel from the cathode to the charge storage plate and back to the anode following a hairpin-path, like trowing a ball towards the ceiling and waiting it fall back to our hands again.
In my opinion, Farnsworth did read one of the French, British or German version of Tihanyi's patent of 1928, and so he filed his US patent 2,087,683 in 1933. They must give the deserved credit to Kalman Tihanyi.
--189.217.191.218 (talk) 16:48, 14 January 2010 (UT
- Actually, There is another pair of coincidences. Farnsworth explicitly said in his US patent number 2,087,683 that the velocity of the stream as it approaches the screen is so low that substantially no secondary emission of electrons occurs [[3]]; and Tihanyi explicitly said in his US patent 2,158,259 that When the cathode ray beam designated 31 strikes the photoelectric areas, it causes the positive charges to be neutralized [[4]], so that Tihanyi never considered an electron beam whose velocity should produce "secondary electrons".
- On the other hand, neither the device described by Tihanyi in the US patent 2,158,259 nor that one described by Farnsworth in the patent 2,087,683 was ever reduced to a fully functionally model; see [[5]]. The devises using a low velocity electron scanning beam are so sensible that they can be used for outside broadcasting [[6]]. If Farnsworth ever built a fully functional model of his US patent 2,087,683 filed in 1933, why did he never announce that he was doing outside broadcasting, while Zworykin could not do so?
- It is also said that Farnsworth's device is the ancestor of the image orthicon (the American industrial standard for broadcasting). If this is true and Farnsworth ever built a fully functional model of his US patent 2,087,683 filed in 1933, why did he abandon this device and worked instead on the "electron multiplier" image dissector [[7]][[8]] that can only be used in industrial applications [[9]]?
![[9]](http://www.aade.com/tubepedia/1collection/ITTid1.jpg){kind=link}
--148.247.186.142 (talk) 15:24, 19 January 2010 (UTC)
- Yes, you are completely right. Just imagine the work done by the British team. Lubszynski and Rodda invented the super-emitron for EMI on May 12, 1934 [[10]], and 83 days later Blumlein and McGee also invented the cps-emitron (a low velocity electron scanning beam tube) for EMI on August 3, 1934 [[11]] [[12]]. They only needed three years for constructing a fully functional camera and to directly broadcasting the King laying a wreath at the Cenotaph in November 1937, a broadcasting from an exterior location [[13]].
- On the other hand, Farnsworth invented the low velocity electron scanning beam in April 1933 (US patent number 2,087,683), but he was never able to directly broadcast anything from an exterior location, anything outside a well illuminated television studio. Farnsworth had to film the scenes from an exterior location and to project the film onto an image dissector in order to broadcast them.
--189.216.128.152 (talk) 03:37, 20 January 2010 (UTC)
Kálmán Tihanyi built cameras for Roayal Air Force (RAF) in 1929. Later he build for Italians. His inventions was a very good models for the Air Forces, they were much better than the camera models of civil world. —Preceding unsigned comment added by 84.0.251.130 (talk) 16:55, 7 April 2010 (UTC)
In reference to user talk 14 January 2010, specifically the statement that Farnsworth must have read the French, British or German version of Tihanyi's 1928 patent, it bears repeating that GB 313,456 representing the version originally filed in all countries, including the US--where however it was divided into separate patents for transmitter respective receiver--was published in England and was naturally available to every serious researcher in the field. The abstract (that is an unusually detailed version with many diagrams included) of GB 313.345 was published already on August 8, 1929, (the full patent in January 1931) in the Official Journal (Patents) of the British Patent Office. (The patent departments of large companies and serious research firms usually subscribe to these official journals or gazettes.) The abstract of Tihanyi's second 1928 application, GB 315,362, a huge patent, was published on September 4, 1929 (the full patent in February 1931).
It is important to understand that Tihanyi never thought of anything else than low velocity scanning beam. As early as October 22-23, 1926, in a manuscript in his own handwriting outlining manufacturing details of his television transmitter, he makes reference to low velocity scanning and adds some remarks regarding the care that must be observed when adjusting beam velocity.
Frankly, a serious and objective discussion of his contributions can only be achieved through a thorough study of GB 313.456 and GB 315,352. (User talk. Hermes. 14 April 2010) —Preceding unsigned comment added by 193.6.201.128 (talk) 18:20, 14 April 2010 (UTC)
- Do you have any reference where we can read about Tihanyi talking on the low velocity scanning beams and how they prevent the emission of secondary electrons?, it would be quite interesting to read Tihanyi's own ideas on this subject.--189.216.116.26 (talk) 18:17, 9 May 2010 (UTC)
The inventor of the first automatic cruise missile
editPlease correct the Kálmán Tihanyi article, his invention was more than a transmission system, it was an automatic optical-controlled aerial torpedo, He invented the world's first cruise missile.
GB patent GB352035 , The Arial Torpedo was not just a simple TV-transmission system. The infracamera could contoroll the aerial torpedo with a special gyro system. It was the first so-called cruise missile.
352,035. Optical apparatus. TIHANYI, K., 324, Juranies telep D.l.Úp, Budapest. Dec. 21, 1929, No. 39195. Convention date, Dec. 16. [Class 97 (i).] Relates to devices for automatically directing telescopes, range-finders, &c., in which an image of the target is distributed on one or more light or heat sensitive cells connected in a balanced circuit, the movement of the target producing out of balance currents which actuate steering mechanism. The invention consists in providing means for automatically varying the angle of vision in accordance with the size of the image of the target. Varying the angle of vision. Two cells 93, 94, Fig. 17, are connected, or feed valves 96, 97, connected in a balanced circuit such as a Wheatstone bridge. One cell 93 is illuminated by an image 98 of the target and the other cell is illuminated by an image of an empty portion of the field of the target.; Should the size of the image of the target increase, the balance of the bridge is disturbed and the resulting out of balance current, after amplification at 95, actuates a variable diaphragm such as in Fig. 15 by rotating one or both of the apertured discs 88, 89. Steering in one plane. In the complete device of Fig. 12 an image of the target 2 is reflected from a mirror 67 through a biprism 9 on to cells 59, 60, 61 of which the cells 59, 60 control the diaphragm 57 as described above. The cells 60, 61 are connected in a balanced circuit and out of balance currents produced by the movements of the target and amplified at 68 may steer the torpedo &c. or may actuate a mirror 67 which distributes light from a source 51 on to two cells 65, 69. The cells 65, 69 are balanced and out of balance currents after amplification at 64 may control the steering mechanism.; The relay comprising mirror 67 and cells 65, 69 may be duplicated to add sensitivity and need not be an optical system. Short-wave electromagnetic radiation may be used and controlled by the currents from amplifier 62. This device steers in one plane only. The biprism 9 may be replaced by mirrors or an internally reflecting prism. The cells 60, 61 may comprise bolometer threads 34, 35, Fig. 8, rotating in the plane of the image and connected by commutators into the arms of a Wheatstone bridge. Spatial steering. By distributing the image over four cells 30 .. 33, Fig. 7, connected in pairs in two balanced circuits such as Wheatstone bridges, movements of the target produce two out of balance currents which are used to control the steering in two planes at right-angles. The photo-electric cells 30 .. 33 are enclosed in a common vacuum and have a common cathode 19.; A slotted shutter may rotate before the cells, exposing each cell in turn to the image. Circuit arrangements. The cells for producing steering currents and those for controlling the diaphragm may be combined as in Fig. 18 in which the cells 60, 61 control the diaphragm and the cells 59, 61 control the steering. Details. The device may be enclosed in heat or magnetic protective casings and may have electrical instruments mounted on it or contacts for such instruments. The device may be fitted to be controlled by radiation from the sending station for at least part of the time. The target may be irradiated with energy to which the device is particularly sensitive.
A multi-spectral detection system and method for detecting radiation from a single target within frequency bands that are in diverse portions of the electromagnetic spectrum. The system includes common radiant energy collection elements for collecting radiant energy of different width wavelength bands from a single target feature in the diverse portions of the electromagnetic spectrum and focusing the collected energy to a common focal point; a waveguide positioned at the focal point for transferring the collected radiant energy away from the focal point; an imaging system for dispersing the transferred energy into separate beams having spectral regions respectively corresponding to the diverse portions of the electromagnetic spectrum, with the beams being of uniform cross sectional dimension notwithstanding said different widths, and for focusing the separate beams to a common plane for detection by separately positioned detectors; and separate detectors of uniform cross-sectional area positioned for respectively detecting the separate beams and adapted for respectively detecting energy in the separate spectral regions of the separate beams. Various imaging systems including focusing prisms and focusing grating systems are disclosed.
Richiesti:
I claim:
1. A multi-spectral detection system for detecting radiation from a single target feature within frequency bands that are in diverse portions of the electromagnetic spectrum, comprising common radiant energy collection means for collecting radiant energy of different width wavelength bands from a single target feature in said diverse portions of the electromagnetic spectrum and focusing said collected energy to a common focal point, imaging means for dispersing said collected energy into separate beams having spectral regions respectively corresponding to said diverse portions of the electromagnetic spectrum, with the beams being of uniform cross-sectional dimension notwithstanding said different widths, and for focusing the separate beams to a common plane for detection by separately positioned detections means; and separate detection means of uniform cross-sectional area positioned in the common plane for respectively detecting energy in the separate spectral regions of the separate beams.
2. A system according to claim 1, wherein the imaging means comprises a focusing prism for dispersing said collected energy into said separate beams and for focusing said separate beams for detection by the separately positioned detection means.
3. A system according to claim 1, wherein the imaging means comprises a lens for directing the collected energy to the mirrored surface of a Littrow prism; and a Littrow prism for dispersing said directed energy into said separate beams and disposed for reflecting said separate beams to the lens to cause the lens to focus said separate beams for detection by the separately positioned detection means.
4. A multi-spectral detection method for detecting radiation from a single target feature within frequency bands that are in diverse portions of the electromagnetic spectrum, comprising the steps of (a) collecting radiant energy from a single target feature in said diverse portions of the electromagnetic spectrum; (b) focusing said collected energy to a common focal point; (c) dispersing said collected energy into separate beams having spectral regions respectively corresponding to said diverse portions of the electromagnetic spectrum, with the beams being of uniform cross-sectional dimension notwithstanding said diversity, and for focusing the separate beams to a common plane for detection by separately positioned detection means; and (d) separately detecting energy in the separate spectral regions of the separate beams with separate detection means of uniform cross-sectional area.
Description:
BACKGROUND OF THE INVENTION
The present invention generally pertains to radiant energy collection systems and is particularly directed to an improvement in multi-spectral target detection systems. A multi-spectral target detection system may be used for detecting radiation in diverse portions of the electromagnetic spectrum.
Radio frequency and electro-optical radiation detection systems have been employed to detect the presence of and/or track moving and stationary targets and to measure some of their characteristics. The uses of these systems range from the detection of military targets to the spectral analysis of molten metals.
When separate detectors for detecting radiation from a single target within diverse portions of the electromagnetic spectrum are placed in a common focal plane defind by a radiant energy collection system, the separate detectors do not view the same target feature (and possibly not even the same target) at the same time unless they are axially coincident. This means that several undesirable effects can occur as the target moves or is scanned.
First, not all of the detectors may ever see the same target feature. Second, there is no prdetermined order in which the separate detectors may see a given feature of the target. Third, the separate detectors see either different features of the target or different targets altogether at any given instant. As a result of the first case, no meaningful comparison of radiant energy received by the separate detectors can occur. The second case necessitates complex signal processing for comparison purposes, which produces target misses and false alarms. The third can also results in target misses and false alarms.
If the separate detectors in the same focal plane are axially coincident, they are difficult and expensive to build and lose efficiency due to fabrication and internal absorption.
SUMMARY OF THE INVENTION
The present invention is a multi-spectral target detection system and method that enables full utilization of all of the collected radiation in the diverse portions of the spectrum, thereby enabling simultaneous wavelength analysis of the same feature of the detected target.
The present invention is a multi-spectral detection system and method for detecting radiation from a single target feature within frequency bands that are in diverse portions of the electromagnetic spectrum. The system of the present invention includes common radiant energy collection elements for collecting radiant energy of different width wavelength bands from a single target feature in the diverse portions of the electromagnetic spectrum and focusing the collected energy to a common focal point; an imaging system for dispersing the collected energy into separate beams having spectral regions respectively corresponding to the diverse portions of the electromagnetic spectrum, with the beams being of uniform cross sectional dimension notwithstanding said different widths, and for focusing the separate beams to a common plane for detection by separately positioned detectors; and separate detectors of uniform cross-sectional area positioned for respectively detecting the separate beams and adapted for respectively detecting energy in the separate spectral regions of the separate beams.
Additional features of the present invention are described with reference to the description of the preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic diagram of a preferred embodiment of the system of the present invention.
FIGS. 2 through 7 are schematic diagrams of the imaging portion of various alternative preferred embodiments of the system of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment of the system of the present invention, as shown in FIG. 1, includes a Cassegrain radiant energy collection system 10, a waveguide 12, an imaging system 14 and a plurality of detectors 16, 17. The Cassegrain system 10 includes a primary mirror 19 and a secondary mirror 20. The Cassegrain system 10 collects radiant energy from a single target in diverse portions of the electromagnetic spectrum, such as the visible blue light and infrared portions, and focuses the collected energy in the diverse portions of the spectrum to a common focal point 22.
The waveguide 12 is preferably a light pipe or an optical fiber. The waveguide 12 is coaxially positioned at the focal point 22 for transferring the collected radiant energy away from the focal point 22. The waveguide 12 has a termination 24, from which the transferred energy emerges in a diverging beam 25.
In other embodiments, waveguides having integral rounded end portions or having auxiliary lens arrangements positioned adjacent the waveguide ends can be used to emit the transferred energy in converging or parallel beams.
In still other embodiments, the waveguide 12 can be omitted, whereby the collected energy passes directly from the collection system 10 to an imaging system, which disperses the collected energy into separate beams.
Referring again to the embodiment of FIG. 1, the imaging system includes a first lens 27, a prism 28 and a second lens 29. The first lens 27 collimates the diverging beam 25 to provide a collimated beam 30. The prism 28 disperses the collimated beam 30 into separate beams 31, 32 having spectral regions respectively corresponding to the diverse portions of the spectrum. The second lens 29 focuses the separate beams 31, 32 for detection by the detectors 16, 17.
The detectors 16, 17 are separately positioned for respectively detecting the separate beams 31, 32. The detectors 16, 17 are adapted for respectively detecting energy in the separate spectral regions of the separate beams 31, 32. Each of the detectors 16, 17 preferably includes a sensor 34, 35 and a waveguide 37, 38 positioned for transferring the detected energy of the respective separate beams 31, 32 to the sensor 34, 35. The waveguide 37, 38 is preferably a light pipe or an optical fiber.
Various alternative preferred embodiments of the imaging system portion of the system of the present invention are shown in FIGS. 2 through 7.
Referring first to the embodiment shown in FIG. 2, the imaging portion of the system is a focusing immersed grating system including an element 40. The element 40 has a curved surface 41 for refracting the emergent energy beam 25 that diverges from the termination 24 of the waveguide 12. The back surface 42 of the element 40 is planar and mirrored and has a grating 43 etched thereon for dispersing the incident beam 25 into separate beams 45, 46 having spectral regions respectively corresponding to the diverse portions of the spectrum. The dispersed beams 45, 46 are refracted by the concave surface to provide separate beams 45', 46'. The mirrored surface 42 is disposed at such an angle as to cooperate with the concave surface 41 to cause the separate beams 45', 46' to be focused respectively for detection by the separately positioned detector waveguides 37, 38. In an alternative embodiment the back surface 42 of the element 40 may be curved.
Referring to the embodiment shown in FIG. 3, the imaging portion of the system is a focusing grating system including a lens 50 and a planar mirror 51. The lens 50 is a concave-convex lens for directing the emergent energy beam 25 that diverges from the termination 24 of the waveguide 12 to the mirror 51. The mirror 51 has a mirrored surface 52 having a grating 53 thereon for dispersing the emergent beam 25 directed thereto by the lens 50 into separate beams 55, 56 having spectral regions respectively corresponding to diverse portions of the spectrum. The mirror 51 is disposed at an angle for reflecting the separate beams 55, 56 toward the lens 50 to cause the lens 50 to focus the separate beams 55, 56 for detection by the separately positioned detector waveguides 37, 38.
Referring to the embodiment shown in FIG. 4, the imaging portion of the system is a focusing grating system including a Cassegrain imaging system having a primary mirror 58 and a secondary mirror 59 and a planar mirror 60. The Cassegrain system 58, 59 directs the emergent energy beam 25 that diverges from the termination 24 of the waveguide 12 to the planar mirror 60. The mirror 60 has a mirrored surface 61 having a grating 62 thereon for dispersing the emergent beam 25 directed thereto by the Cassegrain system 58, 59 into separate beams 64, 65 having spectral regions respectively corresponding to diverse portions of the spectrum. The mirror 60 is disposed at an angle for reflecting the separate beams 64, 65 toward the Cassegrain system 58, 59 to cause the Cassegrain system to focus the separate beams 64, 65 for detection by the separately positioned detector waveguides 37, 38.
The use of the Cassegrain system 58, 59 enables a larger mirror 60 to be used, thereby enabling the use of a larger number of lines in the grating 62 for dispersing the emergent beam 25. The resolution of the resultant image of the target is enhanced by using a larger number of grating lines.
Referring to the embodiment shown in FIG. 5, the imaging portion of the system is a focusing grating system including an element 67. The element 67 has a concave mirrored surface 68 having a grating 69 thereon for dispersing the emergent energy beam 25 that diverges from the termination 24 of the waveguide 12 into separate beams 71, 72 having spectral regions respectively corresponding to diverse portions of the spectrum. The element 67 is disposed for causing the concave mirrored surface 68 to focus the separate beams 71, 72 for detection by the separately positioned detector waveguides 37, 38.
Referring to the embodiment shown in FIG. 6, the imaging portion of the system is a focusing prism 74, having a curved mirrored back surface 75 and a curved front surface 76. The curved front surface 76 refracts the emergent energy beam 25 that diverges from the termination 24 of the waveguide 12 and directs the emergent beam 25 to the curved back surface 75. The prism 74 disperses the emergent beam 25 into separate beams 77, 78 having spectral regions respectively corresponding to diverse portions of the spectrum. The prism 74 also focuses the separate beams 77, 78 for detection by the separately positioned detector waveguides 37, 38.
Referring to the embodiment shown in FIG. 7, the imaging portion of the system includes a lens 80 and a Littrow prism 81. The Littrow prism 81 has a mirrored surface 82. The lens 80 is a concave-convex lens for directing the emergent beam 25 that diverges from the termination 24 of the waveguide 12 to the mirrored surface 82 of the prism 81.
The Littrow prism 81 disperses the directed emergent beam 25 into separate beams 83, 84 having spectral regions respectively corresponding to diverse portions of the spectrum. The Littrow prism 81 is disposed at an angle for reflecting and refracting the separate beams 83, 84 toward theWhy no original images from the "Radioskop" patent are included? lens 80 to cause the lens 80 to focus the separate beams 83, 84 for detection by the separately positioned detector waveguides 37, 38.
The use of prisms takes advantage of the prism's nonlinear index of refraction versus wavelength characteristic to enable energy beams of different width wavelength bands to be focused to detector waveguides 37, 38 having approximately the same cross-sectional area.
If in any of the above-described embodiments, the physical type or positioning of the elements of the imaging portion of the system causes harmonics or subharmonics of energy in the primary frequency band of one separate beam to be focused to the detector which is intended to detect energy in a different primary band, wavelength sensitive filters are used with the respective detectors. —Preceding unsigned comment added by 84.2.105.86 (talk) 10:02, 9 April 2010 (UTC)
Copyright problem removed
editPrior content in this article duplicated one or more previously published sources. The material was copied from: http://www.webcitation.org/query?url=http://www.geocities.com/neveyaakov/electro_science/tihanyi.html&date=2009-10-26+20:59:48. Infringing material has been rewritten or removed and must not be restored, unless it is duly released under a compatible license. (For more information, please see "using copyrighted works from others" if you are not the copyright holder of this material, or "donating copyrighted materials" if you are.) For legal reasons, we cannot accept copyrighted text or images borrowed from other web sites or published material; such additions will be deleted. Contributors may use copyrighted publications as a source of information, but not as a source of sentences or phrases. Accordingly, the material may be rewritten, but only if it does not infringe on the copyright of the original or plagiarize from that source. Please see our guideline on non-free text for how to properly implement limited quotations of copyrighted text. Wikipedia takes copyright violations very seriously, and persistent violators will be blocked from editing. While we appreciate contributions, we must require all contributors to understand and comply with these policies. Thank you. Diannaa (Talk) 14:29, 19 April 2011 (UTC) -Diannaa (Talk) 14:29, 19 April 2011 (UTC)
File:Radioskop 1926.png Nominated for Deletion
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Why no original images from the "Radioskop" patent are included?
editThe following web page contains three images from the original "Radioskop" patent [14]. The three images are all signed by Tihanyi at the lower left corner, and one can even read in one of them the file number of the patent (T-3768) and the year (1926).
On the other hand, it is impossible to understand what is really the "new physical phenomenon" discovered by Tihanyi. One can firstly read a description of the new phenomenon in Tihanyi's words, so far, so good. Then there is a supposed explanation which mentions the photovoltaic and the photoconductive effects.
The central question is which one of the following three phenomena was indeed discovered by Tihanyi: the storage effect (or principle), the photovoltaic effect, or the photoconductive effect?
As far as I know, Alexandre-Edmond_Becquerel discovered the photovoltaic effect in 1839; and Willoughby_Smith discovered the photoconductive effect in selenium in 1873 [[15]].
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