Abstract:
A method and apparatus for manufacturing high-frequency oscillator elements from a workpiece material includes a tool holder formed of magnetic material providing a magnetic field at a tip thereof and a spherical whetstone made of a magnetic material. A grinding mount is made of a magnetic material installed on a main rotating shaft proximate the tool holder through which flux of the magnetic field is channeled. The spherical whetstone held at the tip of the tool holder by magnetic attraction. The workpiece material is mounted on the grinding mount and the tool holder is rotated around an axis coincident with a center of the spherical whetstone while bringing the spherical whetstone into engagement with the workpiece material to lap the workpiece material.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a lapping technology for quartz oscillators, quartz resonators, or optical lenses, which are then machined to be as small, thin, and precise as possible in order to transmit and receive electromagnetic waves at higher frequencies. 
     The conventional lapping techniques for quartz oscillators and quartz resonators consist of machining by barrel lapping, plane lapping, curve generators, etc. 
     In the case of mechanical lapping, the most common lapping limit for quartz oscillators and resonators is approximately 27.8 μm in a planar shape. The resonant primary frequency corresponds to 60 MHz at besl Further, it is impossible for quartz oscillators with holders coupled to grooves in convex and concave lens shapes to be lapped in an extremely thin and small fashion. This also limits the resonant transmitting primary frequency to approximately 60 MHz at best for conventional lapping methods. Mobile communication equipment, for example, amplifies frequencies from 60 MHz to several Ghz because the dimensional size cannot be smaller. The main demerit here is that the electrical power consumption is increased due to the steady direct current in the frequency amplifying circuit. Also, the lower transmitting frequency has resulted in a limited assignment of wave frequencies for mobile communications. 
     SUMMARY OF THE INVENTION 
     The objective of the present invention is to manufacture quartz oscillators, quartz resonators, or optical lenses to be as small, thin, and precise as possible, and to transmit and receive electromagnetic waves at a higher frequency than has previously been allowed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a vertical cross section of the spherical whetstone that is used to lap quartz in the method of the present invention. 
     FIGS. 2 and 3 are a vertical cross section and the plan diagram, respectively. They show the cylindrical holder that holds the whetstone in a spherical shape. 
     FIG. 4 is a vertical cross section of an example of a lapping apparatus for quartz oscillators of the present invention. 
     FIG. 5 is a vertical cross section of an example of a typical holder of the present invention. 
     FIG. 6 is a vertical cross section of another example of a holder of the present invention. 
     FIGS. 7 and 8 are a vertical cross section and a plan view, respectively, that show another example of a lapping apparatus for quartz oscillators of the present invention. 
     FIG. 9 is a vertical cross section of another example for a lapping apparatus of quartz oscillators of the present invention. 
     FIGS. 10-13 are vertical cross sections that show other examples of a lapping apparatus for quartz oscillators of the present invention. 
     FIG. 14 is a vertical cross section of the lapped state of the present invention. 
     FIGS. 15-21 are vertical cross sections that show other examples of a lapping apparatus for quartz oscillators of the present invention. 
     FIGS. 22 and 23 are a vertical cross section and a plan view, respectively, that show the magnetic table. 
     FIG. 24 is a vertical cross section of the lapping apparatus for quartz. 
     FIG. 25 is a plan view of the plate. 
     FIG. 26 is a vertical cross section of the lapping apparatus for said quartz. 
     FIG. 27 is a vertical cross section of the magnetic plate of the present invention. 
     FIGS. 28-30 are vertical cross sections that show the lapping apparatus for quartz of the present invention. 
     FIGS. 31 and 32 are vertical cross sections of the spherical whetstone of the present invention. 
     FIGS. 33-36 are vertical cross sections that show the lapping apparatus for quartz of the present invention. 
     FIGS. 37-41 are vertical cross sections that show the object machined by the lapping process of the present invention. 
     FIGS. 42-44 are vertical cross sections that show a holding method example for lapped material of the present invention. 
     FIGS. 45-49 are a plan showing an example of the plastic part that holds the lapped material. 
     FIG. 50 is a vertical cross section of the assembled state for the lapped material with a magnetic plate. 
     FIGS. 51 and 52 are a front view and a plan view, respectively, that show the doughnut-shaped plate that connects the lapped material to the magnetic plate. 
     FIGS. 53 and 54 are vertical cross sections of the lapping apparatus for quartz of the present invention. 
     FIG. 55 is a vertical cross section that shows the assembled state of the lapped material. 
     FIGS. 56-58 are vertical cross sections that show the lapping apparatus for quartz of the present invention. 
     FIGS. 59-61 are vertical cross sections that show one holding method for the lapped material. 
     FIG. 62 is the plan for FIG.  61 . 
     FIG. 63 is a vertical cross section that shows another holding method for the lapped material. 
     FIG. 64 is the plan for the lapping state during the starring motion (rotation and revolution) of the lapped material of the present invention. 
     FIG. 65 illustrates the locus of the starring motion. 
     FIGS. 66 and 67 are vertical cross sections that show a holding example for the lapped material. 
     FIGS. 68 and 69 are cross sections that show the lapped state of the present invention. 
     FIGS. 70-73 are cross sections that show the lapped material after the lapping process of the present invention. 
     FIGS. 74-84 are diagrams of measured data for the lapped material in various shapes after executing the lapping by the manufacturing method of the present invention. 
     FIGS. 85-89 are diagrams of the reactance frequency characteristics actually measured for the quartz after the machining process. 
    
    
     DETAILED DESCRIPTION 
     The following explanation gives examples of the present invention. 
     FIGS. 1-15 are examples executed by the present invention. In each Fig., number  3  is a chuck,  4  is lapped material,  12  is a lapping tool,  14  is an adhesive,  15  is a holding part,  31  is a spherical whetstone,  32  is a holder,  33  is an adhesive film with a hole,  34  is glass,  35  is a table,  36  is a grinding plate or diamond grain surface,  37  is a hole,  38  is a table in a vessel shape,  39  is a cooling solvent,  40  is a holder,  41  is a lid,  42  is a thin frozen layer,  43  is a connection part,  44  is a magnetic part,  48  is a magnet holder,  49  is a spherical grinding element of spherical material and  50  is a lapping agent of magnetic material. 
     FIG. 1 is a vertical cross section of the spherical whetstone  31  for lapping the quartz. The spherical whetstone  31 , whose diameter may range form approximately 1 mm to several cm, is made of nearly spherical iron steel or other materials. On the surface of the spherical whetstone  31 , a lapping agent is coated having diamond grains  36  or other substances by means of electroplating, evaporation, CVD process, thermally solidified bond, thermally solidified metal, adhesive, or glue. Thus the whetstone surface or the diamond grain surface  36  is formed. 
     FIGS. 2 and 3 are a vertical cross section and a plan view, respectively, that show an example of holder  40  for holding the spherical whetstone  31 . As shown in these FIGS., the holder part  32  of the holder  40  is shaped to be hemispherical in order to be able to support the upper half part of the spherical whetstone  31 . The magnet part  44  is installed at a center of the holder  32 . 
     FIG. 4 shows the first example of a lapping machine for quartz oscillators. The magnetic induction of the grinding mount  35  supports the spherical whetstone  31  inside the holder  40  to lap the workpiece material  4 . Then, since the holder  40  is rotated around its axis line to use the spherical whetstone  31  with the holder  40 , the center line of the spherical whetstone  31  always matches the central axis of the holder  32 , and the highest possible lapping accuracy can be achieved. 
     FIG. 5 shows another example of the holder. The magnetic holder  48  supports the spherical grinding element  49  by means of the magnetic induction of the table  35 . The shape of the holding part  32  of the magnetic holder  48  is that of a sphere, a cone, or a similar shape. The holding part  32  of spherical or conical shape supports the spherical grinding element  49 , and the spherical grinding element  49  laps by a whetstone surface or diamond grains  50 . Therefore, the center line of the spherical grinding element  49  is always equal to the central axis line of the magnetic holder  48 , and the highest possible lapping accuracy can be achieved. 
     FIG. 6 shows another example of the magnetic holder  48 . The magnetic holder  48  supports the spherical whetstone  31  with the magnetic induction of the table  35 . The holding part  32  for the magnetic holder  48  is spherical, conical, or of a similar shape. Since the surface of the whetstone  31  or diamond grain  36  laps the material by using the spherical or conical holder part  32  supporting the spherical whetstone  31 , the center line of the spherical or conical holding part  32  always becomes the same as the center axis line of the spherical whetstone  31 . The lapping accuracy is extremely high. 
     FIGS. 7 and 8 are a vertical cross section and a plan view, respectively, that show another example of the lapping apparatus for quartz oscillators of the present invention. In this example, after the workpiece material  4  is installed on the table  35 , which has an electric magnet or a permanent one, a adhesive film with the hole  37  is attached in order to machine solely the lapped material in the hole. Since the magnetic lapping agent  50  is attracted by the magnetic force on the surface of the spherical grinding element  49 , the holder  40  with the magnetic part  44  is installed at the center of the holding part  32  with the non-magnetic part The workpiece material  4  is rotated to be machined in the shape of a concave lens. 
     FIG. 9 is a vertical cross section of another example of a lapping apparatus for quartz oscillators of the present invention. In this example, the workpiece material  4  is installed on the grinding mount  35  made of a permanent magnet or an electric magnet, and an adhesive film  33  with a hole  37  is attached in order to machine solely the workpiece material  4  in the hole. The workpiece material  4  is rotated to be machined in a convex shape when the spherical whetstone  31  with the lapping surface or diamond grain surface  36  is installed by magnetic force to the holder  40 , which has the magnetic part  44  at the center of the non-magnetic holding part  32 . 
     FIGS. 10-13 are vertical cross sections of another example of a lapping apparatus for quartz oscillators of the present invention. In this example, the workpiece material  4  is installed on the grinding mount  35  made of a permanent magnet or an electric magnet, and adhesive film  29  or glass  34  is attached in order to fix the workpiece material  4 . On the adhesive film  29  or glass  34 , the spherical whetstone  31 , or the spherical grinding element  49 , is held by the magnetic force of the magnetic induction by using the holder  40  which has the magnetic part  44  at the center of the holding part  32 . The workpiece material  4  is rotated to be machined in the shape of a concave lens. For the example in FIG. 13, the workpiece material  4  is also rotated by holding the grinding mount  35  with the chuck  3  of the lathe. 
     FIG. 14 shows an example of the spherical material  49 , which is connected to the holder  40  by forming the connecting part  43  with a screw, an adhesive agent, welding, or other means after matching the center line of the holder  40  to the spherical grinding element  49 . In this example, the holder  40  is directly connected to the grinding element  49 . It is used as said lapping apparatus. 
     FIG. 15 shows an example of the spherical grinding element  49  connected to the holder  32  by forming the connecting part  43  with a screw, an adhesive agent, welding, or other means. This is done after the center line of the holding part  32 , whose tip is cylindrical or another similar geometrical shape, matches the spherical whetstone  31 . The holder  40  is directly connected to the spherical whetstone  31 . The diamond grains are fixed to the surface of the spherical whetstone  31  by utilizing electroplating, electroless plating, or other techniques. This is used as the lapping apparatus. 
     The example of the present invention shown in FIG. 16 is explained below. FIG. 16 is a schematic diagram of a structural drawing of how to lap quartz oscillators. FIGS. 16,  17 ,  18 ,  19 ,  20 ,  21 ,  22 ,  24 ,  26 ,  27 ,  28 ,  29 , and  30  are vertical cross sections. FIGS. 23 and 25 are plan views. In these FIGS., the number  3  is the chuck,  4  is the lapped material,  14  is the adhesive,  31  is the spherical shaped whetstone,  32  is the holding part,  33  is the adhesive film with a hole,  35  is the table,  36  is the whetstone surface,  40  is the holder,  48  is the magnet holder,  149  are ball bearings,  51  is the table,  52  is the air turbine, and  60  is grooves. 
     FIGS. 18,  26 ,  28 , and  29  show the shaving or lapping state of the machined object while the spherical whetstone  31  is attracted and fixed to the end part of the magnet holder  4  by using the grinding mount  35  having magnet or magnetic induction between the grinding mount  35  and the magnetic table  51 . 
     As shown in FIG. 18, a lapped material, such as quartz, is attached on the table  35 , which is comprised of a magnet installed on the primary axis of the machine by means of the adhesive agent The magnet holder  48 , which is rotated by an air turbine, is installed perpendicular to or at an arbitrary angle to the machining axis. The spherical whetstone  31 , whose surface is coated with diamond lapping grains, is attracted by magnetic induction. At the same time, the lapping primary axis rotates at a rate of approximately 300 rpm. The spherical whetstone  31  rotates at nearly 8,000 rpm. The workpiece material  4 , such as quartz as a heterogeneous crystal, is shaved precisely and lapped between them. Since the diameter of the magnet holder  48  is smaller than that of the table  35 , the magnetic flux between the spherical whetstone  31  and the magnet holder  48  is stronger than that between the spherical whetstone  31  and the table  35 . Therefore, as the spherical whetstone  31  made of the magnet attracted to the end of the magnet holder  48  in the shape of a cylinder or a similar geometrical shape, the spherical whetstone  31  and the magnet holder  48  are connected strongly. Moreover, the spherical whetstone  31  can be easily changed due to the magnetic induction of the grinding mount  35 . Since the position of the spherical center is unchanged after the exchange, we can easily and effectively machine at a high accuracy by using for finishing a fine spherical whetstone  31  after a coarse spherical whetstone  31 . 
     FIGS. 22 and 23 show a side view and back view, respectively, of the magnetic table  51 , which is in the same cylindrical shape as that of the cylindrical grinding mount  35  made of the magnet. The back surface of the magnet table  51  has circular grooves. The workpiece material  4  made of a heterogeneous material such as quartz is attached at the center with pine resin, and the pine resin is mixed with wax, or another resin. Also, as seen in FIG. 25, the grooves  60  are installed at the central part of the table  35 . FIG. 25 is a side view diagram of the present lapping apparatus for quartz. The circular grooves  60 , which are machined on the magnetic table  51 , and the grinding mount  35  are used along with ball bearings  149 . The center line of the magnet table  51  becomes equal to that of grinding mount  35  due to the principle of slide bearing. 
     FIG. 26 shows a lapping configuration for a lapping apparatus for quartz. The magnetic table  51  attached to the workpiece material  4  is connected to the central part of the grinding mount  35  installed at the side of the machining primary axis. The workpiece material  4  is machined in the shape shown in FIG.  27 . Again as shown in FIG. 28, the central line of the magnet table  51  becomes equal to that of the workpiece material  4 . The workpiece material  4  is attached with pine resin, pine resin mixed with wax, or another resin. Also, due to the principle of the slide bearing, the center line of the grinding mount  35  is equal to that of the magnet table  51  attached by facing the non-machined surface of the workpiece material  4  as well as by using the magnetic table  51 , the circular grooves around the table  35 , and the ball bearing  149 . Then, the workpiece material  4  is machined by the spherical whetstone  31  and by rotating the non-machined surface of the spherical material  4  with the air turbine  52 . 
     FIGS. 29 and 30 show the direct matching state between the center line of the grinding mount  35  and that of the magnetic table  51 . In FIG. 30, the center line of the magnetic table  51  is directly connected to that of the chuck  3 , and the lapped object  4  is machined. 
     An example of the present invention shown in FIG. 31 is explained below. FIG. 31 is a schematic diagram of the structural drawings of how to machine quartz oscillators. FIGS. 31-41 are vertical cross sections. In these FIGS, number  3  is the chuck,  4  is the lapped material,  5  is the vacuum chuck,  31  is the spherical whetstone,  32  is the holding part,  33  is the adhesive film with a hole,  35  is the table,  36  is the whetstone surface,  48  is the magnet holder,  49  is the spherical grinding element, and  50  is the lapping grain. 
     FIGS. 31 and 32 show the state of the lapping surface  36 , which is formed partially on the spherical whetstone  31  by electroplating or electroless plating, on the spherical grinding element  49 . Also the whetstone surface  36  can be formed totally on the spherical whetstone  31 . 
     FIGS. 33 and 34 show the shaving or lapping state of the workpiece material  4  while the spherical whetstone  31  is attracted and fixed to the end part of the holder  32  at the tip of the magnet holder  48  by using the magnetic induction of the grinding mount  35  made of a magnet. The spherical whetstone  31  held at the end of the magnet holder  48  rotates at over 10,000 rpm. Also, the workpiece material  4  is shaved and lapped by rotating it as shown in FIGS. 33 and 34. The spherical whetstone  31  is attracted to the holder  32  at the end of the magnet holder  48  due to the magnetic induction of the table  35 . The workpiece material  4  is sandwiched between the grinding mount  35  and the spherical whetstone  31 . Thus, whenever the workpiece material  4  is machined in an extremely thin state it will not be destroyed, even if it is impacted by vibration due to machining errors or other reasons, and the workpiece material  4  can be shaved and machined precisely. FIGS. 35 and 36 show the lapping and machining processes of the finished lapped material  12  in the shapes of convex and concave lenses. 
     FIGS. 37-41 show the finished lapped material  12 , which is shaved and machined from the workpiece material  4  by the spherical whetstone  31  in FIGS. 30,  31  and  32  by the method seen in FIGS. 14,  15 ,  16 ,  18 ,  28 ,  29 ,  33 ,  34 ,  35 , and  36 . FIG. 37 shows the finished lapped material  12  in a planar shape. FIG. 38 shows the finished lapped material  12  in a plano-convex shape, FIG. 39 in a convex lens shape, and FIGS. 40 and 41 in a concave lens shape. 
     FIGS. 42 through 49 show the state of the workpiece material  4  contacted and attached to the magnetic table  51  or a staggered magnetic table  93 , whose U-shaped part is attached with a heated resin such as pine resin. The workpiece material  4  is installed on the table. Pressure is imposed on the workpiece material  4  by the magnetic force of the magnetic table  51  and the staggered magnetic table  93 , as well as by using a cylindrical shaped object  66  or a cylindrical shaped magnet  67  on the cylindrical shaped object  66 , which is made of iron capped by a plastic part  68  on the workpiece material  4 . The plastic part  68  at the end of the cylindrical object  66  or the cylindrical magnet  67  is made from polycarbonate or other materials. The central part of the plastic part  68  is in a hollow cylindrical shape. It is similar to a screw or a bolt Then, the workpiece material  4  is attached to the magnet table  51  by the pressure of the magnetic force from the magnet table  51 , and even an extremely thin lapped material, such as quartz, cannot be ruptured. 
     FIG. 43 shows the workpiece material  4  connected to the plastic part  68  by the tip attraction pressure of a vacuum tube  69  through a hole  70  of the cylindrical object  66  or the cylindrical magnet  67 . Moreover, the magnetic table  51  is formed in a convex shape in order to ease the positioning of the attached workpiece material  4 . The workpiece material  4  is attached with adhesive  14  on the convex part. 
     FIGS. 51 and 52 are, respectively, the front view and a cross section that show a doughnut-shaped table  89  used to connect the workpiece material  4  to the magnetic table  51 . FIG. 50 is a side view of the doughnut-shaped table  89 , which is connected to the magnetic table  51 . The doughnut-shaped table  89  is comprised of a sandwich structure of a thin, non-magnetic plate  90  and a magnetic ring  91 . As shown in FIG. 50, the heterogeneous crystal workpiece material  4  is attached directly by the magnetic force of the magnetic table  51  to the surface center of the cylindrical magnetic table  51  similar to the diameter of magnetic cylindrical table  35 , or else the workpiece material  4  is attached by the surface tension of the water on the surface of a piece of wet suede  85  on the magnetic table  51 . Also, the workpiece material  4  can be attached to the magnetic table  51  with pine resin or a mixed resin of wax and other materials. 
     FIG. 53 shows the absorbed state of the magnetic table  51 , which is attached to the workpiece material  4 , on the central part of the table  35 , which is in a spherical shape and is installed at the side of the mechanical primary axis. In order to match the central axis of the magnetic table  51  to that of the table  35 , the central axis of the magnetic table  51  is made identical to that of the grinding mount  35  by utilizing the principle of the slide bearing with plural ball bearing  149  and grooves  60 , which are machined on the circumference of the magnetic table  51  and the table  35 . After the workpiece material  4  is machined by the spherical whetstone  31  as shown in FIG. 54, the central axis of the magnetic table  51  is matched to that of the lapping surface for the workpiece material  4 , and the workpiece material  4  is attached on the magnetic table  51  by using resins etc. as shown in FIG.  55 . Again, by using the slide bearing principle that uses the ball bearings  149  and the grooves  60  made on the magnetic table  51  and the circumference of the table  35 , the non-lapped surface of the workpiece material  4  is machined by rotating the air turbine  52 . FIGS. 57 and 58 show the lapping process of the workpiece material  4  when the magnetic table  51  is directly connected to the table  35 , whose cylindrical shape is exactly identical to the magnetic table  51 . 
     FIG. 57 shows the lapping process of the workpiece material  4  when the magnetic table  51  is attracted to the central axis of the magnetic chuck  3  by magnetic force. Also, FIG. 58 shows the lapping state of the workpiece material  4 , where the spherical shaped whetstone  31  is supported by force of the magnetic holder  48  or the vacuum chuck  5  in a cylindrical or conical shape. 
     FIG. 59 shows that the workpiece material  4 , where one side or both sides are shaved and lapped, is thickly attached with an adhesive  14  on the surface of a cylindrical shaped part  102 . FIG. 59 also shows that the workpiece material  4  becomes thicker when a ring-shaped holder  105 , which is as thick as the workpiece material  4  and is made from aluminum or other materials, is simply placed without the adhesive  14  around the exterior surface of the workpiece material  4 . One side is lapped with a cylindrical shaped part  102 , which is made from plastics, metals such as aluminum and super steel, or other materials. The other side of the workpiece material  4  is lapped with the ring-shaped holder  105  by using a carrier of a two-sided lapping machine. Then, an ultra thin example  12  can be easily lapped. Furthermore, the two-sided lapping machine enables the parallel, planer and flat surface to easily obtain higher accuracy. 
     FIG. 60 shows a circular U-shaped part  106 , which is approximately as thick as or nearly as high as the workpiece material  4  where one or both sides are lapped, which is machined or molded by using plastics or metals such as aluminum. The workpiece material  4  is attached with the adhesive  14  on part of the U-shaped part  106 , or else the workpiece material  4  is simply connected to the U-shaped part  106  without the adhesive  14 . As seen in FIG. 59, the exterior part of the workpiece material  4  is formed and protected by the ring-shaped holder  105 , whose height is equal to or less than that of the workpiece material  4 . A U-shaped part  106  makes the workpiece material  4  thicker. This is because the workpiece material  4  is attached with the adhesive  14  on part of the U-shaped part  106  or it is simply connected without the adhesive  14 . One side is lapped with the U-shaped part  106  made from plastics or metals such as aluminum by using a carrier of a two-sided lapping machine. The other side is lapped with both the workpiece material  4  and the ring-shaped part of the U-shaped part  106  around the workpiece material  4 . Then, the ultra thin sample  12  is easily lapped in the way shown in FIG.  59 . 
     FIGS. 61 and 62 show how a hollow cylindrical material  107  made from metals such as aluminum is placed on the lower surface of a lapping plate  62 . The cylindrical material  108  is inserted into the hollow cylindrical material  107 , and is a little shorter. The workpiece material  4  is thicker because it is attached on the exterior surface of the cylindrical material  108  by the adhesive  14 , or because the workpiece material  4  is simply connected without the adhesive  14 . As shown in FIG. 63, the upper lapping plate  109  and the lower lapping plate  62  are used to employ the carrier of a two-sided lapping machine. As seen in FIGS. 64 and 65, the structure, which is composed of the hollow cylindrical material  107 , the cylindrical material  108 , and the workpiece material  4 , rotates and revolves in a planetary manner. One side laps the upper surface of the workpiece material  4  with the lapping plate  109 . The other side laps the lower side of the cylindrical material  108  by the lapping plate  62 . The ultra thin lapped material  12  is easily machined. 
     As shown in FIG. 66, the same effect that is seen in FIGS. 61-63 can be obtained, although the separate hollow cylindrical material  107  and the cylindrical material  108  are combined by the adhesive  14  or by a one-sided adhesive tape  200  between the hollow cylindrical material  107  and the cylindrical material  108  as seen in FIG.  67 . 
     Furthermore, in the case of using a one-sided lapping machine as shown in FIG. 68, when the U-shaped part  106  is attached to the magnetic table  51  or when the U-shaped part  106  is suppressed downward by the magnetic force as shown in FIG. 69, the workpiece material  4  is machined in an ultra thin shape by lapping the workpiece material  4 , which is attached to the U-shaped part  106 . 
     Referring FIG. 70, the reaction-frequency characteristics of the very thinly lapped material  12  shown have a spurious oscillation near the resonance region. However, the lapped material  12  of FIGS. 71-73 have an ideal reaction-frequency property with almost no spurious oscillation. 
     FIGS. 74-84 and FIG. 85 show the measured diagrams for a wide variety of the finished lapped material  12  such as quartz. These were obtained by the lapping method shown in FIGS. 18,  56 ,  57 ,  58 ,  59 ,  60 , and  63 . 
     FIGS. 85-89 are measured diagrams of reaction-frequency properties for the finished lapped material  12  as quartz in FIGS. 74 and 79. The measuring instrument used was a Hewlett Packard HP 8753C network analyzer. FIG. 85 shows the data of the finished lapped material  12  in FIG.  74 . FIGS. 86-89 show the data of the finished lapped material in FIG.  77 . The measured data in FIG. 85 have quasi-frequency vibration with exterior spurious oscillation, which corresponds to the finished lapped material  12 . However, the data in FIGS. 85-89 have ideal frequency oscillation of reaction characteristics (impedance). This corresponds to the finished lapped material  12  in FIGS. 77 and 74. The shape of the finished lapped material  12  in FIG. 77 was found to show a different property compared to that in FIG.  74 . 
     The crucial difference is that the shape of the finished lapped material  12  shown in FIG. 74 is planar (flat) at the oscillating part, and that the shape in FIG. 77 is plano-convex (one side is in a convex lens shape). Even in the case of the plano-convex shape, as seen in FIGS. 80 and 81, the ultra in finished lapped material  12  shown in FIGS. 77-81 was found to show almost no spurious oscillation in the vicinity of the primary frequency when the thickness of the convex lens was less than 70 μm. 
     It has commonly been thought that an ideal reaction-frequency oscillation without spurious resonance cannot be obtained unless the shape is bi-convex, as shown in FIG.  73 . However, the ideal reaction-frequency oscillation with almost no spurious resonance as shown in the measured data in FIGS. 86-89 is found to be achievable in the plano-convex shape shown in FIG.  77 . Also, in the plano-convex case, the finished lapped material  12  should be less than 125 μm. 
     The advantages of the finished lapped material  12  in the plano-convex shape in FIG. 72 over the conventional bi-convex shape in FIG. 73 are as follows: 
     1. Since only one side is in a convex lens shape, the crystal axis can be easily matched to the lapping axis. 
     2. Since only one side is convex, it can be as thin as possible as compared with that of the bi-convex shape.  3 . The grooves  27  and the holding part  15  at the convex finished lapped material  12  are easily machined This is the condition in which the oscillation will not be spurious. 
     EFFECT OF THE INVENTION 
     In this invention, a spherical whetstone made of a nearly spherical steel sphere is held freely by magnetic force at the tip of a spherical, cylindrical, or similarly shaped holder, and the whetstone can shave and lap a lapped material as thinly, minutely, and accurately as possible. 
     Quartz oscillators and quartz resonators are required to be as small, thin, and accurate as possible. Conventional theories and machining methods cannot satisfy this requirement. The quartz oscillators and quartz resonators of this invention, however, are manufactured without difficulty in quite thin, small, and accurate shapes. Therefore, quartz oscillators and quartz resonators are able to transmit and receive directly high frequency waves from 600 MHz to 1,000 MHz. This has been impossible with conventional technology. Mobile communication devices such as mobile telephones can be entirely digitized. Those devices can be made as small as business cards. The present invention can be applied to a wide variety of domains such as small high-resolution radar, small radar that automatically stops cars, tiny radar such as robot eyes, small radar for blind people, high resolution electronic microscopes, communication satellites, as well as other domains. 
     In using the present invention, quartz oscillators of the lapped material are shaved or lapped by a rotating holding tool directly connected to the holder after forming an adhesive part on the spherical whetstone, on which a diamond grain surface is made in a purely spherical or nearly spherical shape. The spherical whetstone is made of nearly spherical iron steel in which the diameter ranges from approximately 1 mm to several cm. On the surface of the spherical whetstone, a lapping agent is coated with grains of diamond or other substances by means of electroplating, evaporation, CVD process, etc., and the whetstone surface or the diamond grain surface is formed. Therefore, many lapped materials such as quartz, ceramics, ferrite or others, which are as small as 1-10 mm or larger can be lapped into fine spherical shapes by using the spherical whetstone made of a steel sphere in a nearly pure spherical shape. Since the entire sphere surface of the spherical whetstone can be used and consumption is negligible, the material is lapped in a short time and the machining cost to lap it in a thinner and more accurate shape is cheaper. Also, by using NC machines, the spherical whetstone can be used as a cutting tool to lap many objects in the shape of convex lens, concave lens, non-spherical shapes, and other arbitrary shapes. 
     This novel structure, which is composed of the hollow cylindrical shaped material, the cylindrical shaped material, and the lapped material, rotates and revolves as a planet. One side laps the upper surface with the lapping plate. The other side laps the lower side of the cylindrical material with the lapping plate. An ultra thin material is easily machined. Magnetic force is used to attract the lapped material to the lapping plate. The merits that occur are listed below. 
     1. Since magnetic attraction is used as the lapping pressure (load), the gravity center is lowered to the limit 
     2. The extremely small magnet in the diameter, the length, and the weight make it possible for high lapping pressure (load) to occur. For example, a magnet of 5 mm diameter, 10 mm length and 1.5 g weight can produce a lapping pressure (load) of 150 g. 
     3. Since an extremely small magnet in diameter, length, and weight makes it possible for high lapping pressure (load) to occur, an ultra thin lapped material can be machined. For example, in the case of small quartz without magnetic attraction, other methods cannot load the pressure to the quartz where the diameter is approximately 5 mm. 
     4. The lapped material can attach to the lapping plate as closely as possible. 
     5. Even if the gap between the inner diameter of the carrier and the external diameter becomes smaller, the magnet can draw close to the lapping plate surface and the lapping accuracy becomes excellent because the magnet moves freely up and down inside the carrier hole by using magnetic attraction. 
     The lapped material becomes thicker where a ring-shaped holder is placed without an adhesive around the exterior surface of the lapped material. One side is lapped with the cylindrical shaped part (the so-called “menko” in Japanese). The other side is lapped with a ring-shaped holder by using the carrier of a two-sided lapping machine. An ultra thin sample can be easily lapped. The circular U-shaped part, which is approximately as thick as or nearly as high as the lapped material, is machined or molded by using plastics or metals. The lapped material is attached with an adhesive on part of the U-shaped part, or the lapped material is connected to it without an adhesive. The exterior part of the lapped material is formed and protected by the ring-shaped part, and the U-shaped part makes the lapped material thicker. This is because the lapped material is attached with an adhesive on part of the U-shaped part, or it is simply connected without an adhesive. One side is lapped with the ring-shaped part of the U-shaped part by using the carrier of a two-sided lapping machine. The other side is lapped with both the lapped material and with the ring-shaped part of the U-shaped part around the lapped material. An ultra thin sample is easily lapped by overcoming the defects of the conventional lapping machine as explained below. 
     1. Since the lapped material is attached to the hollow cylindrical part or the U-shaped part, it is lapped as thinly as possible. This is achieved by using the carrier of a two-sided lapping machine. 
     2. The ring-shaped holder, which is as thick as the lapped material, is attached on the entire surface of the lapped material, or the ring shape is formed on the exterior surface of the lapped material, and the lapped material is machined together. Then, the lapped material with a large diameter of the exterior surface attached by the ring shaped holder or the U-shaped part can be machined with fewer dispersed errors than in the case of the lapped material alone. Therefore, the parallel planar accuracy of the lapped material is not only higher than that of the stand-alone lapping, but also cannot be destroyed when it is machined to the thinnest shape possible. 
     3. The main shortcoming of a two-sided lapping machine is that the upper lapping plate rotates counter clockwise while the lower lapping plate rotates clockwise. In other words, the lapped material has a twist stress and the property of the quartz changes due to the residual stress of the two-sided rotation. On the other hand, the lapped material as quartz is not stressed by the twisting force since the two-sided lapping machine moves like a one-sided lapping machine when the upper lapping plate machines the hollow cylindrical part, or when the U-shaped part and the lower lapping plate machines the lapped material as quartz. 
     4. A one-sided lapping machine cannot shave the lapped material in a higher planar accuracy, but a two-sided lapping machine can do it due to the pressure of the upper and lower lapping plates. Therefore, the present invention, which uses a two-sided lapping machine attached to a hollow cylindrical part or a U-shaped part on the lapped material, can improve the parallel planar accuracy of a one-sided lapping machine. This invention can solve the problem of a two-sided lapping machine not being able to lap an ultra thin material such as quartz. It also leaves a residual stress in the ultra thin lapped material due to the twisting force. 
     Quartz oscillators are lapped while the magnetic part of the spherical material, on which the whetstone surface or the diamond grain surface on the spherical shaped whetstone is formed, is magnetized. At the same time the lapped object is machined to be partly planar at the central part of said lapped material in the shape of a convex or concave lens. This is accomplished by the circular surface of said spherical whetstone, whose lapping surface is made by electric gild or non-electric gild on the spherical material. When the circular surface of said spherical whetstone, which is attracted by the magnetic force or the vacuum force of the table, rotates by using the holder, the following merits are obtained 
     1. After the coarse machining is done, the steel sphere with the whetstone surface can be changed easily on the same axis line for fine lapping because the whetstone with the fine lapping surface can be connected smoothly. 
     2. Since the lapped material is machined in a hollow cylindrical, conical, or spherical shape by the tool during the holder state connected to the lapping machine, the holder in a hollow cylindrical or conical shape can be set to the tip of the fine lapping machine on the central axis line with negligible error. 
     3. The steel sphere with the whetstone surface is attracted and connected to the tip of the holder by magnetic induction force, vacuum suction, or magnetic force. Therefore, the central axis line of the hollow cylindrical or conical holder is easily matched to the central line of the steel sphere. The material can be lapped with an extremely high accuracy. 
     INDUSTRIAL APPLICABILITY 
     The present invention can be applied to a wide variety of electronic apparatuses, communication instruments such as mobile telephones and small high resolution radars, and other things that utilize quartz oscillators and quartz resonators in order to transmit and receive stable high frequency waves.