Claims
- 1. A color display device comprisingan in-line electron gun (5) for generating three electron beams (6,7,8) located substantially within a plane extending in an X-direction of a rectangular X-Z coordinate system, deflecting means (51) for deflecting the electron beams (6,7,8), and convergence means (14′) for dynamically influencing the convergence of the electron beams, the convergence means (14′) comprising means for generating a magnetic field that corresponds to a magnetic quadrupole field, said convergence means comprising coils (22′) that comprise electrically conductive wires which have been toroidally wound in a winding-direction and according to a winding density distribution N (φ) given by N (φ)=N0 cos (2φ)+C;,where φ is an angle enclosed by the X-direction and a line between an element of the coil and the center of the coil, which ranges between 0° and 360°, N0 is a given winding density, the sign of N (φ) denotes the winding direction, and C is a constant unequal to zero.
- 2. A color display device according to claim 1, wherein the means for generating a magnetic quadrupole field comprise a ring-shaped element (21′) having said coils (22′).
- 3. A color display device according to claim 2, wherein said coils (22′) of the convergence means (14′) comprise packages (30) of electrically conductive wires, said packages (30) being toroidally wound in a winding direction and according to an approximate winding density distribution N (φ) described byN (φ)=N0 cos (2φ)+C; where φ is an angle enclosed by the X-direction and a line between an element of the package and said center.
- 4. A color display device according to claim 1, wherein the constant C equals +N0.
- 5. A color display device according to claim 1, wherein the constant C equals +N0 or −N0.
- 6. A color display device according to claim 1, wherein the deflecting means (51) comprises a field coil set, and the means for generating a magnetic quadrupole field comprise the field coil set and means for asymmetrically driving the field coil set.
- 7. A color display device comprisingan in-line electron gun (5) for generating three electron beams (6,7,8) located substantially within a plane extending in an X-direction of a rectangular X-Z coordinate system, deflecting means (51) for deflecting the electron beams (6,7,8), and convergence means (14′) for dynamically influencing the convergence of the electron beams, the convergence means (14′) comprising means for generating a magnetic field that corresponds to a magnetic quadrupole field, said means for generating comprising a ring-shaped element (21′) having coils (22′) that comprise electrically conductive wires which have been toroidally wound in a winding direction and according to a winding density distribution N (φ) given by N (φ)=N0 cos (2φ)+C; where φ is an angle enclosed by the X-direction and a line between an element of the coil and the center of the coil, which ranges between 0° and 360°, N0 is a given winding density, the sign of N (φ) denotes the winding direction, and C is a constant, wherein said ring-shaped element (21′) comprises two parts (60,68), a first part (60) being positioned closer to the in-line electron gun (5) than a second part (68), at least one of said parts having the coils (22′).
- 8. A deflection unit (51) comprising deflection coils (13′) and convergence means (14′) for dynamically influencing the convergence of electron beams (6,7,8), to decrease a distance (p) between the electron beams at a location of a deflection plane,the convergence means (14′) comprising a ring-shaped element (21′) having coils (22′), said coils (22′) comprising electrically conductive wires which have been toroidally wound in a winding direction and according to a winding density distribution N (φ) given by N (φ)=N0 cos (2φ)+C; where φ is an angle enclosed by the X-direction and a line between an element of the coil and the center of the coil, which ranges between 0° and 360°, N0 is a given winding density, the sign of N (φ) denotes the winding direction, and C is a constant unequal to zero.
- 9. A deflection unit according to claim 8, wherein said electron beams are generated by an in-line electron gun, and wherein said ring-shaped element (21′) comprises two parts (60,68), a first part (60) being positioned closer to the in-line gun (5) than a second part (68), and at least one of said parts having the coils (22′).
- 10. A method of manufacturing a convergence unit (14′) for dynamically influencing a convergence of electron beams in a color display device (1), the convergence unit (14′) comprising a ring-shaped element (21′) having coils (22′),said method comprising the steps of: providing the ring-shaped element (21′), winding an electrically conductive wire toroidally around the ring-shaped element (21′) in a winding direction and according to a winding density distribution N (φ) given by N (φ)=N0 cos (2φ)+C; where φ is an angle enclosed by the X-direction and a line between an element of the coil and the center, which ranges between 0° and 360°, N0 is a given winding density,.the sign of N (φ) denotes the winding direction, and C is a constant unequal to zero.
- 11. A method of manufacturing a convergence unit according to claim 10, wherein each coil (22′) has layers and the winding step comprises a first step of winding a first layer of each of the coils (22), and at least one further step of winding a further layer of each of the coils (22′).
Priority Claims (1)
Number |
Date |
Country |
Kind |
00201507 |
Apr 2000 |
EP |
|
CROSS-REFERENCE TO RELATED APPLICATION
This application is a Continuation-in-part of U.S. patent application Ser. No. 09/338,049 filed Jun. 22, 1999 (now U.S. Pat. No. 6,411,027) which is a Continuation-in-part of U.S. patent application Ser. No. 09/218,550 filed Dec. 22, 1998, both of which are hereby incorporated by reference.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/EP00/05710 |
|
WO |
00 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO00/79562 |
12/28/2000 |
WO |
A |
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
RE35548 |
Sluyterman et al. |
Jul 1997 |
E |
6031345 |
Nakata |
Feb 2000 |
A |
6376981 |
Sluyterman et al. |
Apr 2002 |
B1 |
Continuation in Parts (2)
|
Number |
Date |
Country |
Parent |
09/338049 |
Jun 1999 |
US |
Child |
09/763303 |
|
US |
Parent |
09/218550 |
Dec 1998 |
US |
Child |
09/338049 |
|
US |