Milestone-Proposal:Invention of Temparature- Insensitive Quartz Oscillation Plate Enabling HIghly Stable Communications and Clocks, 1933: Difference between revisions
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|a9=The Museum is open to the public on weekdays from 10:30 to 16:30. (Closed nights and holidays.) | |a9=The Museum is open to the public on weekdays from 10:30 to 16:30. (Closed nights and holidays.) | ||
|a10=Tokyo Institute of Technology National University Corporation | |a10=Tokyo Institute of Technology National University Corporation | ||
|a4=<div style="margin-left:0cm;margin-right:0cm;">Its technological, scientific, and social importance may be described as follows:</div> | |a4=<div style="margin-left:0cm;margin-right:0cm;">Its technological, scientific, and social importance may be described as follows:</div><br /> | ||
<div style="margin-left:0cm;margin-right:0cm;">'''(1) Pioneering theoretical analysis of the thickness vibrations of quartz oscillation plates'''</div> | <div style="margin-left:0cm;margin-right:0cm;">'''(1) Pioneering theoretical analysis of the thickness vibrations of quartz oscillation plates'''</div> | ||
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<div style="margin-left:0cm;margin-right:0cm;"> Quartz oscillation plates being used in the early 1930s were almost entirely limited to X-cut and Y-cut plates (X and Y axes are perpendicular to the Z-axis). The characteristics of these plates were only known after sectioned measurement. Meanwhile, the resonant frequency of vibration of any isotropic plate is well known and is expressed by:</div> | <div style="margin-left:0cm;margin-right:0cm;"> Quartz oscillation plates being used in the early 1930s were almost entirely limited to X-cut and Y-cut plates (X and Y axes are perpendicular to the Z-axis). The characteristics of these plates were only known after sectioned measurement. Meanwhile, the resonant frequency of vibration of any isotropic plate is well known and is expressed by:</div> | ||
<div style="margin-left:0cm;margin-right:0.196cm;"> </div> | <div style="margin-left:0cm;margin-right:0.196cm;"> </div> | ||
[[File:R1-Cut Quart equation1_1.jpg|left|400px|]] | [[File:R1-Cut Quart equation1_1.jpg|left|400px|]]<br /><br /><br /> | ||
< | |||
<div style="margin-left:0cm;margin-right:0cm;">where "''f''" is resonant frequency, "''a''" is plate thickness, "''ρ''" is density, "''c''" is the adiabatic elastic constant of the medium, and "''q''" is any integer. </div> | <div style="margin-left:0cm;margin-right:0cm;">where "''f''" is resonant frequency, "''a''" is plate thickness, "''ρ''" is density, "''c''" is the adiabatic elastic constant of the medium, and "''q''" is any integer. </div> | ||
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<div style="margin-left:0cm;margin-right:0cm;"> In August of that year, he derived a significant formula for elastic constant "''c''" in Eq. (1) corresponding to the thickness vibration in the case of a quartz crystal plate cut parallel to the X-axis and having its rotating angle ''θ'' about the X-axis. The requisite coefficient ''c<sup>eq<sup>'' is given by the following equation: | <div style="margin-left:0cm;margin-right:0cm;"> In August of that year, he derived a significant formula for elastic constant "''c''" in Eq. (1) corresponding to the thickness vibration in the case of a quartz crystal plate cut parallel to the X-axis and having its rotating angle ''θ'' about the X-axis. The requisite coefficient ''c<sup>eq<sup>'' is given by the following equation: | ||
<div style="margin-left:0cm;margin-right:0.196cm;"> </div> | <div style="margin-left:0cm;margin-right:0.196cm;"> </div> | ||
[[File:R1-Cut Quart equation2_1.jpg|left|400px|]] | [[File:R1-Cut Quart equation2_1.jpg|left|400px|]]<br /><br /><br /> | ||
<div style="margin-left:0cm;margin-right:0cm;">where ''c<sub>ij</sub>'' are adiabatic constants of crystal depending on plate orientation with respect to the crystallographic axes of the medium [2, 3].</div> | <div style="margin-left:0cm;margin-right:0cm;">where ''c<sub>ij</sub>'' are adiabatic constants of crystal depending on plate orientation with respect to the crystallographic axes of the medium [2, 3].</div> | ||
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<div style="margin-left:0cm;margin-right:0cm;"> Thus by employing "''c<sup>eq</sup>''" in place of "''c''" in Eq. (1) Koga expressed the vibrational characteristics of crystalline media as follows:</div> | <div style="margin-left:0cm;margin-right:0cm;"> Thus by employing "''c<sup>eq</sup>''" in place of "''c''" in Eq. (1) Koga expressed the vibrational characteristics of crystalline media as follows:</div> | ||
<div style="margin-left:0cm;margin-right:0.196cm;"> </div> | <div style="margin-left:0cm;margin-right:0.196cm;"> </div> | ||
[[File:R1-Cut Quart equation3.jpg|left|400px|]] | [[File:R1-Cut Quart equation3.jpg|left|400px|]]<br /><br /><br /> | ||
<div style="margin-left:0cm;margin-right:0cm;"> This formula being simple, but containing sufficient information, was published in 1932 for the first time in history. It has been widely referred to by numerous researchers both inside and outside Japan as described below and has become the basis for subsequent development of quartz plates, achieving desired frequencies as well as lower temperature coefficients.</div> | <div style="margin-left:0cm;margin-right:0cm;"> This formula being simple, but containing sufficient information, was published in 1932 for the first time in history. It has been widely referred to by numerous researchers both inside and outside Japan as described below and has become the basis for subsequent development of quartz plates, achieving desired frequencies as well as lower temperature coefficients.</div> | ||
<div style="margin-left:0cm;margin-right:0cm;"> | <div style="margin-left:0cm;margin-right:0cm;"></div><br /> | ||
<div style="margin-left:0cm;margin-right:0cm;">'''(2) Invention of quartz crystal plates with zero temperature-coefficient '''</div> | <div style="margin-left:0cm;margin-right:0cm;">'''(2) Invention of quartz crystal plates with zero temperature-coefficient '''</div> | ||
<div style="margin-left:0cm;margin-right:0cm;">In the early 1930s most oscillators in transmitters used in short-wave radio telecommunications employed the X- or Y-cut plates that were relatively sensitive to temperature variation. Therefore temperature-regulating equipment was indispensable. The use of thermostats for this purpose included such problems as long start-up time and frequent maintenance. Accordingly, demand for quartz crystal plates with a smaller temperature coefficient was increasing.</div> | <div style="margin-left:0cm;margin-right:0cm;"> "In the early 1930s most oscillators in transmitters used in short-wave radio telecommunications employed the X- or Y-cut plates that were relatively sensitive to temperature variation. Therefore temperature-regulating equipment was indispensable. The use of thermostats for this purpose included such problems as long start-up time and frequent maintenance. Accordingly, demand for quartz crystal plates with a smaller temperature coefficient was increasing.</div> | ||
<div style="margin-left:0cm;margin-right:0cm;">Several ideas (for example, ring shaped plates) were tried in order to achieve zero temperature-coefficients, but no practical solution for transmitter use was found.</div | <div style="margin-left:0cm;margin-right:0cm;"> Several ideas (for example, ring shaped plates) were tried in order to achieve zero temperature-coefficients, but no practical solution for transmitter use was found.</div> | ||
<div style="margin-left:0cm;margin-right:0cm;">Around 1930, Issac Koga noticed that the crystallographic face r of positive rhombohedrons displayed various unique characteristics [4]. He believed that plates cut out in parallel to the face r might possess special properties for oscillators, namely R-cut plates (cf. Fig. 1). [[Media:Fig_1.pdf]] Similarly, those plates cut out in parallel to the r' face (reverse side of r face) were thus termed R'-cut. He found several advantages in these R- and R'-cut plates, such as easier excitation, strong oscillatory power, and a smaller temperature-coefficient than for conventional X- and Y-cut plates. He obtained a Japan Patent for this R-cut in April 1932 [5].</div | <div style="margin-left:0cm;margin-right:0cm;"> Around 1930, Issac Koga noticed that the crystallographic face r of positive rhombohedrons displayed various unique characteristics [4]. He believed that plates cut out in parallel to the face r might possess special properties for oscillators, namely R-cut plates (cf. Fig. 1). [[Media:Fig_1.pdf]] Similarly, those plates cut out in parallel to the r' face (reverse side of r face) were thus termed R'-cut. He found several advantages in these R- and R'-cut plates, such as easier excitation, strong oscillatory power, and a smaller temperature-coefficient than for conventional X- and Y-cut plates. He obtained a Japan Patent for this R-cut in April 1932 [5].</div> | ||
<div style="margin-left:0cm;margin-right:0cm;">After the discovery of R-cut and R'-cut, Koga noticed the fact that R'-cut plates have a negative temperature coefficient while the Y-cut yields a positive one. Therefore, he hypothesized the existence of a zero-temperature-coefficient plate between them. He tested plates by rotating the cutting angles around the X-axis from R'-cut (cf. Fig 1, ''θ'' = 51°) to Y-cut (''θ'' = 90°). Koga and his colleague Ichinose clarified the existence of a zero-temperature-coefficient plate (at around ''θ'' = 55°) in their report published in April 1933 for the first time [6] (cf. Fig. 2). [[Media:Fig_2.pdf ]]</div> | <div style="margin-left:0cm;margin-right:0cm;"> After the discovery of R-cut and R'-cut, Koga noticed the fact that R'-cut plates have a negative temperature coefficient while the Y-cut yields a positive one. Therefore, he hypothesized the existence of a zero-temperature-coefficient plate between them. He tested plates by rotating the cutting angles around the X-axis from R'-cut (cf. Fig 1, ''θ'' = 51°) to Y-cut (''θ'' = 90°). Koga and his colleague Ichinose clarified the existence of a zero-temperature-coefficient plate (at around ''θ'' = 55°) in their report published in April 1933 for the first time [6] (cf. Fig. 2). [[Media:Fig_2.pdf ]]</div> | ||
<div style="margin-left:0cm;margin-right:0cm;">Through continued precise theoretical investigation and experiments, Koga discovered the existence of two cutting angles arriving at a zero temperature-coefficient. Pursing closer studies in the region of ''θ'' = 55°, a precise angle of 54° 45′ was determined. These results were reported on October 10, 1933 [7].</div | <div style="margin-left:0cm;margin-right:0cm;"> Through continued precise theoretical investigation and experiments, Koga discovered the existence of two cutting angles arriving at a zero temperature-coefficient. Pursing closer studies in the region of ''θ'' = 55°, a precise angle of 54° 45′ was determined. These results were reported on October 10, 1933 [7].</div> | ||
<div style="margin-left:0cm;margin-right:0cm;">In parallel with his theoretical work, Koga proceeded to produce a practical plate with a zero-coefficient. Finally, for the first time anywhere in the world, he realized a very low temperature-coefficient plate on the order of 10<sup>-7</sup>, while conventional ones (X- and Y-cut, among others) were on the order of 10<sup>-5</sup>. This result was also included in the above-mentioned report of October 10, 1933 [7]. Slightly different examples of quartz plate holders used in Koga's research are shown in Fig. 3 [[Media:Fig_3.pdf]] and Fig. 4. [[Media:Fig_4.pdf ]]</div> | <div style="margin-left:0cm;margin-right:0cm;"> In parallel with his theoretical work, Koga proceeded to produce a practical plate with a zero-coefficient. Finally, for the first time anywhere in the world, he realized a very low temperature-coefficient plate on the order of 10<sup>-7</sup>, while conventional ones (X- and Y-cut, among others) were on the order of 10<sup>-5</sup>. This result was also included in the above-mentioned report of October 10, 1933 [7]. Slightly different examples of quartz plate holders used in Koga's research are shown in Fig. 3 [[Media:Fig_3.pdf]] and Fig. 4. [[Media:Fig_4.pdf ]]</div> | ||
<div style="margin-left:0cm;margin-right:0cm;">Some ten days after Koga's announcement, a similar theoretical prediction (the existence of two types of zero-temperature-coefficient plates) was reported on October 20, 1933 by a German researcher, R. Bechmann of Telefunken Co. In this report, Koga's earlier paper written in 1932 [3] was cited as a reference, an event detailed below in the present document.</div> | <div style="margin-left:0cm;margin-right:0cm;"> Some ten days after Koga's announcement, a similar theoretical prediction (the existence of two types of zero-temperature-coefficient plates) was reported on October 20, 1933 by a German researcher, R. Bechmann of Telefunken Co. In this report, Koga's earlier paper written in 1932 [3] was cited as a reference, an event detailed below in the present document.</div> | ||
<div style="margin-left:0cm;margin-right:0cm;">Koga discovered another possible zero-temperature-coefficient angle: 137°59′. That work was published in December 1933 [8]. It was these cuts that were later called R<sub>1</sub>- and R<sub>2</sub>-cut, respectively.</div> | <div style="margin-left:0cm;margin-right:0cm;"> Koga discovered another possible zero-temperature-coefficient angle: 137°59′. That work was published in December 1933 [8]. It was these cuts that were later called R<sub>1</sub>- and R<sub>2</sub>-cut, respectively.</div> | ||
<div style="margin-left:0cm;margin-right:0cm;">In July 1934, a similar result for zero-temperature-coefficient plates was reported in the ''Bell System Technical Journal'' under the names of AT- and BT-cut. This nomenclature remains in use today, but is substantially the same as Koga's R<sub>1</sub>- and R<sub>2</sub>-cuts -common enough occurrence in scientific and engineering fields.</div> | <div style="margin-left:0cm;margin-right:0cm;"> In July 1934, a similar result for zero-temperature-coefficient plates was reported in the ''Bell System Technical Journal'' under the names of AT- and BT-cut. This nomenclature remains in use today, but is substantially the same as Koga's R<sub>1</sub>- and R<sub>2</sub>-cuts -common enough occurrence in scientific and engineering fields.</div><br /> | ||
<div style="margin-left:0cm;margin-right:0cm;">'''(3) Development and practical design of crystal clocks in Japan using stable quartz oscillators'''</div> | <div style="margin-left:0cm;margin-right:0cm;">'''(3) Development and practical design of crystal clocks in Japan using stable quartz oscillators'''</div> | ||
<div style="margin-left:0cm;margin-right:0cm;">Koga believed from the earliest stage of his research on quartz oscillation that one important application areas would be crystal clocks, able to provide dependable time and frequency standards.</div> | <div style="margin-left:0cm;margin-right:0cm;"> Koga believed from the earliest stage of his research on quartz oscillation that one important application areas would be crystal clocks, able to provide dependable time and frequency standards.</div> | ||
<div style="margin-left:0cm;margin-right:0cm;">He proposed and developed various types of crystal clocks using his stable oscillation plates. The first model (KQ-1) was designed in 1936 and first demonstrated at the 1937 Paris International Exposition (Fig. 5). [[Media:Fig_5.pdf]] He continued the improvement of quartz clocks (models KQ-2 to KQ-5) until the 1950s in cooperation with Tokyo Astronomical Observatory (Fig. 6). [[Media:Fig_6.pdf]] The final model (KQ-6) was designed in 1955 for professional uses. It was installed in Kokusai Denshin Denwa Co., Ltd. (KDD), where it operated satisfactorily for more than ten years as a time-and-frequency standard (note Fig. 7 [[Media:Fig_7.pdf]] and Fig. 8 [[Media:Fig_8.pdf]]).</div> | <div style="margin-left:0cm;margin-right:0cm;"> He proposed and developed various types of crystal clocks using his stable oscillation plates. The first model (KQ-1) was designed in 1936 and first demonstrated at the 1937 Paris International Exposition (Fig. 5). [[Media:Fig_5.pdf]] He continued the improvement of quartz clocks (models KQ-2 to KQ-5) until the 1950s in cooperation with Tokyo Astronomical Observatory (Fig. 6). [[Media:Fig_6.pdf]] The final model (KQ-6) was designed in 1955 for professional uses. It was installed in Kokusai Denshin Denwa Co., Ltd. (KDD), where it operated satisfactorily for more than ten years as a time-and-frequency standard (note Fig. 7 [[Media:Fig_7.pdf]] and Fig. 8 [[Media:Fig_8.pdf]]).</div> | ||
<div style="margin-left:0cm;margin-right:0cm;"> </div> | <div style="margin-left:0cm;margin-right:0cm;"> </div> | ||
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<div style="margin-left:0cm;margin-right:0cm;">'''(4) Social importance of the invention of temperature-insensitive quartz crystal oscillation plates'''</div> | <div style="margin-left:0cm;margin-right:0cm;">'''(4) Social importance of the invention of temperature-insensitive quartz crystal oscillation plates'''</div> | ||
<div style="margin-left:0cm;margin-right:0cm;">Utilization of quartz oscillation plates having zero temperature-coefficient of frequency has made possible the elimination of inconvenient temperature regulators (thermostats) in telecommunication stations. This is especially important for mobile and portable radio communication systems. </div> | <div style="margin-left:0cm;margin-right:0cm;"> Utilization of quartz oscillation plates having zero temperature-coefficient of frequency has made possible the elimination of inconvenient temperature regulators (thermostats) in telecommunication stations. This is especially important for mobile and portable radio communication systems. </div> | ||
<div style="margin-left:0cm;margin-right:0cm;">At the present time, the generation of stable frequency signals by quartz crystal is indispensable in such applications as smartphone, Internet, and PC. It is not too much to say that our current daily lifestyle would be unimaginable without temperature-insensitive quartz technology applications. </div> | <div style="margin-left:0cm;margin-right:0cm;"> At the present time, the generation of stable frequency signals by quartz crystal is indispensable in such applications as smartphone, Internet, and PC. It is not too much to say that our current daily lifestyle would be unimaginable without temperature-insensitive quartz technology applications. </div> | ||
<div style="margin-left:0cm;margin-right:0cm;">Several examples of oscillation plates (from past to present-day) are shown in Fig. 9. [[Media:Fig_9.pdf]] The current worldwide distribution of quartz-based industries is displayed in Fig. 10. [[Media:Fig_10.pdf]]</div> | <div style="margin-left:0cm;margin-right:0cm;"> Several examples of oscillation plates (from past to present-day) are shown in Fig. 9. [[Media:Fig_9.pdf]] The current worldwide distribution of quartz-based industries is displayed in Fig. 10. [[Media:Fig_10.pdf]]</div><br /> | ||
<div style="margin-left:0cm;margin-right:0cm;">All Figures of Fig. 1 to Fig. 10 refered in the above paragraphs are shown with the following linking .</div> | <div style="margin-left:0cm;margin-right:0cm;">All Figures of Fig. 1 to Fig. 10 refered in the above paragraphs are shown with the following linking .</div> | ||
[[Media:Fig.1_to_Fig.10.pdf]]<br /> | |||
[[Media:Fig.1_to_Fig.10.pdf]] | |||
<div style="margin-left:0cm;margin-right:0.196cm;"> | |a6=<div style="margin-left:0cm;margin-right:0.196cm;"> From the early 1930s, a consistently higher stability of oscillation frequency for transmitting stations became an issue in order to avoid mutual interference in realizing government and industry requirements. No systematic design principles had been established. In such circumstances Koga perceived at once that a theory for analyzing the behavior of anisotropic quartz vibrations had to be found. His research overcame obstacles to this realization in two ways</div><br /> | ||
<div style="margin-left:0cm;margin-right:0.196cm;"> | <div style="margin-left:0cm;margin-right:0.196cm;">(1) In establishing a systematic method of analysis in order to regulate thickness vibration, basic equations for strict anisotropic quartz crystal had encountered considerable complexity. Thus, in order to simplify these issues, Koga first studied the vibration of simple isotropic crystals making reference to Lamb's theory for normal elastic bodies. By a further extension, he obtained a general formulation for true anisotropic quartz crystals. His theory, which included the essential formula (2) given in this document (section B-1), was published in August 1932 in several English-language journals [2, 3] and was soon being referred to by researchers worldwide.</div><br /> | ||
<div style="margin-left:0cm;margin-right:0.196cm;">(2) After the theoretical prediction of a zero-temperature-coefficient plate (R<sub>1</sub>-cut) in April 1933, Koga set out to realize an actual plate having zero (or near-zero) temperature-coefficient. The problem to be overcome was how to obtain the precise angle of cutting an R<sub>1</sub> plate corresponding to its theoretically estimated value (54°45′ rotating about the X-axis) within a ± 1/100 degree margin of error.</div> | <div style="margin-left:0cm;margin-right:0.196cm;">(2) After the theoretical prediction of a zero-temperature-coefficient plate (R<sub>1</sub>-cut) in April 1933, Koga set out to realize an actual plate having zero (or near-zero) temperature-coefficient. The problem to be overcome was how to obtain the precise angle of cutting an R<sub>1</sub> plate corresponding to its theoretically estimated value (54°45′ rotating about the X-axis) within a ± 1/100 degree margin of error.</div> | ||
<div style="margin-left:0cm;margin-right:0.196cm;">Koga and his group solved this problem by introducing an X-ray diffractometer, succeeding at last in the production of a plate having a temperature coefficient of less than 10<sup>-7</sup> (almost two digits smaller than those of existing X- and Y-cut plates).</div> | <div style="margin-left:0cm;margin-right:0.196cm;"> Koga and his group solved this problem by introducing an X-ray diffractometer, succeeding at last in the production of a plate having a temperature coefficient of less than 10<sup>-7</sup> (almost two digits smaller than those of existing X- and Y-cut plates).</div> | ||
<div style="margin-left:0cm;margin-right:0.196cm;"> </div> | <div style="margin-left:0cm;margin-right:0.196cm;"> </div> | ||
|a5=<div style="margin-left:0cm;margin-right:0.196cm;">'''(1) Koga's achievement'''</div> | |a5=<div style="margin-left:0cm;margin-right:0.196cm;">'''(1) Koga's achievement'''</div> | ||
<div style="margin-left:0cm;margin-right:0.196cm;">Issac Koga started his study of quartz crystal oscillators following Cady's initial discovery (1922) of quartz plate oscillation. At that time, investigations of quartz oscillation were mostly undertaken experimentally by making actual oscillation plates without any back-up design principle. In order to overcome the inherent complexities, Koga strove successfully to establish a precise theory for the vibration analysis of quartz plates.</div> | <div style="margin-left:0cm;margin-right:0.196cm;"> Issac Koga started his study of quartz crystal oscillators following Cady's initial discovery (1922) of quartz plate oscillation. At that time, investigations of quartz oscillation were mostly undertaken experimentally by making actual oscillation plates without any back-up design principle. In order to overcome the inherent complexities, Koga strove successfully to establish a precise theory for the vibration analysis of quartz plates.</div><br /> | ||
<div style="margin-left:0cm;margin-right:0.196cm;">& | <div style="margin-left:0cm;margin-right:0.196cm;"> Koga's work may be summarized as follows: | ||
*Theory of crystal vibration | *Theory of crystal vibration | ||
In 1932, when Koga established his precise theoretical analysis of thickness vibration of anisotropic quartz crystal, no similar theory existed. Therefore, Koga's theory [2 and 3] was readily adopted in the field together with the practice of rotating the cutting angle around the crystallographic axis. |  In 1932, when Koga established his precise theoretical analysis of thickness vibration of anisotropic quartz crystal, no similar theory existed. Therefore, Koga's theory [2 and 3] was readily adopted in the field together with the practice of rotating the cutting angle around the crystallographic axis. | ||
 This contributed worldwide to the application of zero-temperature-coefficient quartz plates. | |||
This contributed worldwide to the application of zero-temperature-coefficient quartz plates. | |||
*Zero-temperature-coefficient plates | *Zero-temperature-coefficient plates | ||
In late 1929 and early 1930, several proposals appeared for realization of zero-temperature-coefficient plates. Among them, a ring-type plate was considered promising, however it was unusable in actual transmitters owing to delicate design constraints. |  In late 1929 and early 1930, several proposals appeared for realization of zero-temperature-coefficient plates. Among them, a ring-type plate was considered promising, however it was unusable in actual transmitters owing to delicate design constraints. | ||
 As explained, Koga concentrated on producing a zero-temperature-coefficient plate by rotating the cutting angle along the X-axis and realized an actual plate having a zero-coefficient in 1933 [7]. Similar work was being done in Europe and US, and this may be summarized as follows:</div><br /> | |||
As explained, Koga concentrated on producing a zero-temperature-coefficient plate by rotating the cutting angle along the X-axis and realized an actual plate having a zero-coefficient in 1933 [7]. Similar work was being done in Europe and US, and this may be summarized as follows:</div><br /> | |||
<div style="margin-left:0cm;margin-right:0.196cm;">'''(2) Early work in Germany''' | <div style="margin-left:0cm;margin-right:0.196cm;">'''(2) Early work in Germany''' | ||
After Koga's realization of zero-temperature-coefficient (in fact, “near-zero”) plates on October 10, 1933, Bechmann of Telefunken Co., independently reported theoretical prediction of the existence of two types of zero-temperature-coefficient plates. In this report, Koga's 1932 paper [3] was offered as a starting point. (cf. ''Naturwissenschaften'', Vol. 21, No. 42, p. 752, October 20, 1933) |  After Koga's realization of zero-temperature-coefficient (in fact, “near-zero”) plates on October 10, 1933, Bechmann of Telefunken Co., independently reported theoretical prediction of the existence of two types of zero-temperature-coefficient plates. In this report, Koga's 1932 paper [3] was offered as a starting point. (cf. ''Naturwissenschaften'', Vol. 21, No. 42, p. 752, October 20, 1933) | ||
<div style="margin-left:0cm;margin-right:0.196cm;">'''(3) Successive work at Bell Labs (US)''' | <div style="margin-left:0cm;margin-right:0.196cm;">'''(3) Successive work at Bell Labs (US)''' | ||
In July 1934, Lack, Willard, and Fair of Bell Laboratories in the US reported zero-temperature-coefficient plates by rotating the cutting angle about X axis starting from Y-cut crystals. The two types of plates were named AT- and BT-cut. Presently the terms AT and BT are still widely used, however they are substantially the same as Koga's earlier respective R<sub>1</sub>- and R<sub>2</sub>-cut (cf. ''Bell System Technical Journal'', p. 453, July 1934). |  In July 1934, Lack, Willard, and Fair of Bell Laboratories in the US reported zero-temperature-coefficient plates by rotating the cutting angle about X axis starting from Y-cut crystals. The two types of plates were named AT- and BT-cut. Presently the terms AT and BT are still widely used, however they are substantially the same as Koga's earlier respective R<sub>1</sub>- and R<sub>2</sub>-cut (cf. ''Bell System Technical Journal'', p. 453, July 1934). | ||
<div style="margin-left:0cm;margin-right:0.196cm;">'''(4) Seiko's IEEE Milestone: Quartz Wristwatch''' | <div style="margin-left:0cm;margin-right:0.196cm;">'''(4) Seiko's IEEE Milestone: Quartz Wristwatch''' | ||
 The wristwatch achieved by the firm of Suwa Seikosha in 1969 has already been filed as an IEEE Milestone (2004). In this case, quartz oscillators use a different type of vibration mode, namely a tuning-fork. This is because frequency must be lower (some 32 kHz) than that used for communication purposes in order be accommodated within a very compact space. | |||
The wristwatch achieved by the firm of Suwa Seikosha in 1969 has already been filed as an IEEE Milestone (2004). In this case, quartz oscillators use a different type of vibration mode, namely a tuning-fork. This is because frequency must be lower (some 32 kHz) than that used for communication purposes in order be accommodated within a very compact space. |  Although Koga proposed tuning-fork vibration components in his studies before hitting upon a strict zero-temperature-coefficient vibrator R<sub>1</sub>-cut, the significance of the present Milestone Proposal differs greatly from that awarded Seiko. Therefore, the wristwatch Milestone in no way detracts from the originality of the present Issac Koga proposal.</div> | ||
Although Koga proposed tuning-fork vibration components in his studies before hitting upon a strict zero-temperature-coefficient vibrator R<sub>1</sub>-cut, the significance of the present Milestone Proposal differs greatly from that awarded Seiko. Therefore, the wristwatch Milestone in no way detracts from the originality of the present Issac Koga proposal.</div> | |||
[[File:R1-cut Quartz Table 1.jpg|left|800px|]] | |||
<div style="margin-left:0cm;margin-right:0cm;"> Koga's pioneering studies in the theory and technologies of quartz oscillation continued unabated, in collaboration with his group (cf. Fig. 11) after World War II (including [11] and [12]). These works have further contributed to the establishment of present-day quartz technologies. </div><br /> | |||
|references=<div style="margin-left:0cm;margin-right:0.196cm;">(Note)<br />In the references listed below, Koga's affiliated university name ''“Tokyo University of Engineering”'' refers to the older English appellation of the present-day “Tokyo Institute of Technology”.</div> | |references=<div style="margin-left:0cm;margin-right:0.196cm;">(Note)<br /> In the references listed below, Koga's affiliated university name ''“Tokyo University of Engineering”'' refers to the older English appellation of the present-day “Tokyo Institute of Technology”.</div> | ||
<div style="margin-left:0cm;margin-right:0.196cm;"> </div> | <div style="margin-left:0cm;margin-right:0.196cm;"> </div> |
Revision as of 11:20, 13 January 2016
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Docket #:2015-15
This Proposal has been approved, and is now a Milestone
To the proposer’s knowledge, is this achievement subject to litigation?
Is the achievement you are proposing more than 25 years old?
Yes
Is the achievement you are proposing within IEEE’s designated fields as defined by IEEE Bylaw I-104.11, namely: Engineering, Computer Sciences and Information Technology, Physical Sciences, Biological and Medical Sciences, Mathematics, Technical Communications, Education, Management, and Law and Policy. Yes
Did the achievement provide a meaningful benefit for humanity? Yes
Was it of at least regional importance? Yes
Has an IEEE Organizational Unit agreed to pay for the milestone plaque(s)? Yes
Has an IEEE Organizational Unit agreed to arrange the dedication ceremony? Yes
Has the IEEE Section in which the milestone is located agreed to take responsibility for the plaque after it is dedicated? Yes
Has the owner of the site agreed to have it designated as an IEEE Milestone? Yes
Year or range of years in which the achievement occurred:
1933
Title of the proposed milestone:
Invention of Temperature-Insensitive Quartz Oscillation Plate Enabling Highly Stable Communications and Clocks, 1933
Plaque citation summarizing the achievement and its significance:
200-250 word abstract describing the significance of the technical achievement being proposed, the person(s) involved, historical context, humanitarian and social impact, as well as any possible controversies the advocate might need to review.
IEEE technical societies and technical councils within whose fields of interest the Milestone proposal resides.
In what IEEE section(s) does it reside?
IEEE Tokyo Section
Exective Committee Member
Chair of History Committe, IEEE Tokyo Section
Member of History Committee, IEEE Japan Council
Haruo Okuda
IEEE Organizational Unit(s) which have agreed to sponsor the Milestone:
IEEE Organizational Unit(s) paying for milestone plaque(s):
IEEE Organizational Unit(s) arranging the dedication ceremony:
IEEE section(s) monitoring the plaque(s):
Milestone proposer(s):
Proposer name: Kenichi IGA
Proposer email: Proposer's email masked to public
Proposer name: Taiji Nishizawa
Proposer email: Proposer's email masked to public
Please note: your email address and contact information will be masked on the website for privacy reasons. Only IEEE History Center Staff will be able to view the email address.
Street address(es) and GPS coordinates in decimal form of the intended milestone plaque site(s):
2–12–1, O-okayama, Meguro-ku, Tokyo, 152-8550 Japan
Describe briefly the intended site(s) of the milestone plaque(s). The intended site(s) must have a direct connection with the achievement (e.g. where developed, invented, tested, demonstrated, installed, or operated, etc.). A museum where a device or example of the technology is displayed, or the university where the inventor studied, are not, in themselves, sufficient connection for a milestone plaque.
Please give the address(es) of the plaque site(s) (GPS coordinates if you have them). Also please give the details of the mounting, i.e. on the outside of the building, in the ground floor entrance hall, on a plinth on the grounds, etc. If visitors to the plaque site will need to go through security, or make an appointment, please give the contact information visitors will need.
Are the original buildings extant?
Yes, the Main Building of the Institute. (See photograph in Fig. 12)
Details of the plaque mounting:
In a special showcase at the Exhibition Room of the Institute Museum
How is the site protected/secured, and in what ways is it accessible to the public?
The Museum is open to the public on weekdays from 10:30 to 16:30. (Closed nights and holidays.)
Who is the present owner of the site(s)?
Tokyo Institute of Technology National University Corporation
What is the historical significance of the work (its technological, scientific, or social importance)? If personal names are included in citation, include justification here. (see section 6 of Milestone Guidelines)
What obstacles (technical, political, geographic) needed to be overcome?
What features set this work apart from similar achievements?
- Theory of crystal vibration
In 1932, when Koga established his precise theoretical analysis of thickness vibration of anisotropic quartz crystal, no similar theory existed. Therefore, Koga's theory [2 and 3] was readily adopted in the field together with the practice of rotating the cutting angle around the crystallographic axis. This contributed worldwide to the application of zero-temperature-coefficient quartz plates.
- Zero-temperature-coefficient plates
In late 1929 and early 1930, several proposals appeared for realization of zero-temperature-coefficient plates. Among them, a ring-type plate was considered promising, however it was unusable in actual transmitters owing to delicate design constraints.
As explained, Koga concentrated on producing a zero-temperature-coefficient plate by rotating the cutting angle along the X-axis and realized an actual plate having a zero-coefficient in 1933 [7]. Similar work was being done in Europe and US, and this may be summarized as follows:After Koga's realization of zero-temperature-coefficient (in fact, “near-zero”) plates on October 10, 1933, Bechmann of Telefunken Co., independently reported theoretical prediction of the existence of two types of zero-temperature-coefficient plates. In this report, Koga's 1932 paper [3] was offered as a starting point. (cf. Naturwissenschaften, Vol. 21, No. 42, p. 752, October 20, 1933)
In July 1934, Lack, Willard, and Fair of Bell Laboratories in the US reported zero-temperature-coefficient plates by rotating the cutting angle about X axis starting from Y-cut crystals. The two types of plates were named AT- and BT-cut. Presently the terms AT and BT are still widely used, however they are substantially the same as Koga's earlier respective R1- and R2-cut (cf. Bell System Technical Journal, p. 453, July 1934).
The wristwatch achieved by the firm of Suwa Seikosha in 1969 has already been filed as an IEEE Milestone (2004). In this case, quartz oscillators use a different type of vibration mode, namely a tuning-fork. This is because frequency must be lower (some 32 kHz) than that used for communication purposes in order be accommodated within a very compact space.
Although Koga proposed tuning-fork vibration components in his studies before hitting upon a strict zero-temperature-coefficient vibrator R1-cut, the significance of the present Milestone Proposal differs greatly from that awarded Seiko. Therefore, the wristwatch Milestone in no way detracts from the originality of the present Issac Koga proposal.Supporting texts and citations to establish the dates, location, and importance of the achievement: Minimum of five (5), but as many as needed to support the milestone, such as patents, contemporary newspaper articles, journal articles, or chapters in scholarly books. 'Scholarly' is defined as peer-reviewed, with references, and published. You must supply the texts or excerpts themselves, not just the references. At least one of the references must be from a scholarly book or journal article. All supporting materials must be in English, or accompanied by an English translation.
In the references listed below, Koga's affiliated university name “Tokyo University of Engineering” refers to the older English appellation of the present-day “Tokyo Institute of Technology”.
Supporting materials (supported formats: GIF, JPEG, PNG, PDF, DOC): All supporting materials must be in English, or if not in English, accompanied by an English translation. You must supply the texts or excerpts themselves, not just the references. For documents that are copyright-encumbered, or which you do not have rights to post, email the documents themselves to ieee-history@ieee.org. Please see the Milestone Program Guidelines for more information.
Media:Photographies_of_Koga's_research_group_and_the_main_building_of_Tokyo_Institute_of_Technology.pdf
Media:Koga's_biography.pdf
Media:Reference_1_Quartz_R1-cut_translated.pdf
Media:Reference_2_Quartz_R1-cut.pdf
Media:Reference_3_Quartz_R1-cut_rev1.pdf
Media:Reference_4_Quartz_R1-cut_translated.pdf
Media:Reference_5_Quartz_R1-cut_translated.pdf
Media:Reference_6_Quartz_R1-cut_translated.pdf
Media:Reference_7_Quartz_R1-cut_translated.pdf
Media:Reference_8_Quartz_R1-cut_translated.pdf
Media:Reference_9_Quartz_R1-cut_rev1.pdf
Media:Reference_10_Quartz_R1-cut_translated.pdf
Media:Reference_11_Quartz_R1-cut_translated.pdf
Media:Reference_12_Quartz_R1-cut.pdf
Media:Reference_1_Quartz_R1-cut_Japanese_rev1.pdf
Media:Reference_4_Quartz_R1-cut_Japanese_rev1.pdf
Media:Reference_5_Quartz_R1-cut_Japanese_rev1.pdf
Media:Reference_6_Quartz_R1-cut_Japanese_rev1.pdf
Media:Reference_7_Quartz_R1-cut_Japanese_rev1.pdf
Media:Reference_8_Quartz_R1-cut_Japanese.pdf
Media:Reference_10_Quartz_R1-cut_Japanese_rev1.pdf
Media:Reference_11_Quartz_R1-cut_Japanese_rev1.pdf
Please email a jpeg or PDF a letter in English, or with English translation, from the site owner(s) giving permission to place IEEE milestone plaque on the property, and a letter (or forwarded email) from the appropriate Section Chair supporting the Milestone application to ieee-history@ieee.org with the subject line "Attention: Milestone Administrator." Note that there are multiple texts of the letter depending on whether an IEEE organizational unit other than the section will be paying for the plaque(s).
Please recommend reviewers by emailing their names and email addresses to ieee-history@ieee.org. Please include the docket number and brief title of your proposal in the subject line of all emails.