KR100813824B1 - Electron gun of double dynamic focus type having subsidiary dynamic lens for cathod ray tube - Google Patents

Abstract

The present invention is a cathode ray tube electron gun in which a plurality of focus electrodes are arranged in series, and a prefocus lens and first and second dynamic quadrupole lenses are formed in series according to a voltage applied to the focus electrodes. In this electron gun, the auxiliary dynamic lenses that perform the same lens functions in the vertical and horizontal directions are formed by the same opening shapes of the exit focus electrode of the first dynamic lens and the incident focus electrode of the second dynamic lens. Is formed. Here, the shape of the opening of the first dynamic lens facing the emission side focus electrode and the second dynamic lens facing the opening electrode is horizontal in the screen coordinate system of the cathode ray tube, whereby the magnification in the vertical direction of the auxiliary dynamic lens is horizontal. It is higher than magnification of direction.

Description

Electron gun of double dynamic focus type having subsidiary dynamic lens for cathod ray tube}

1 is a cross-sectional side view showing the structure of a conventional color cathode ray tube.

Figure 2 is a block diagram showing a driving device of a conventional double dynamic focus cathode ray tube.

3 is a perspective view showing the internal structure of a conventional double dynamic focus type cathode ray tube electron gun.

4 is a waveform diagram illustrating a relationship between driving voltages of a conventional dual dynamic focus method.

FIG. 5A is a view illustrating electron lenses formed at a time when the static focus voltage is higher than the dynamic focus voltage in the electron gun of FIG. 3.

FIG. 5B is a view illustrating electron lenses formed at a time when the static focus voltage is lower than the dynamic focus voltage in the electron gun of FIG. 3.

6 is a perspective view showing the internal structure of the electron beam for the cathode ray tube of the dual dynamic focus method according to an embodiment of the present invention.

FIG. 7 is a view illustrating electron lenses formed in the electron gun of FIG. 6.                 

8A is a graph showing the relationship of the vertical diameter to the dynamic focus voltage of one electron spot when constant vertical and horizontal deflection voltages are applied to the electron gun of FIG. 3.

FIG. 8B is a graph showing the relationship of the vertical diameter to the dynamic focus voltage of one electron spot when constant vertical and horizontal deflection voltages are applied to the electron gun of FIG. 6.

<Explanation of symbols for the main parts of the drawings>

1 ... cathode tube, 11 ... electron gun,

12 panels, 13 funnels,

13a ... neck, 13b ... corner,

14 ... fluorescent membrane, 15 ... deflection yoke,

Vfs ... static focus voltage, Vfd ... dynamic focus voltage,

Sc ... composite video signal, Th ... horizontal deflection cycle,

Vec ... screen voltage, Veb ... anode voltage,

K ... cathode, C ... control electrode,

S ... screen electrode, F1, ..., F6 ... focus electrode,

A ... final acceleration electrode, 21 ... video signal processor,

22 ... vertical deflection signal generator, 23 ... horizontal deflection signal generator,

24 ... vertical deflection signal amplifier, 25 ... horizontal deflection signal amplifier,

26 ... retrace signal amplifier, 27 ... data signal amplifier,                 

31, ..., 34 ... bias supply, 35 ... dynamic focus drive,

36 ... heater power supply, A _V ... vertical zone,

A _H ... horizontal area, S _L ... prefocus lens,

Q _L1V , Q _L1H ... 1 dynamic quadrupole lens, M _L ... main lens,

Q _L2V , Q _L2H ... second dynamic quadrupole lens, P _B ... direction of movement of electron beams,

F _V , F _H ... vector of force applied to electron beams, S _SL ... secondary static lens,

SD _L ... secondary dynamic lens,

Dsv ... Vertical diameter of the horizontal outer spot.

The present invention relates to an electron gun for a cathode ray tube of a dual dynamic focus method, and more particularly, a plurality of focus electrodes are arranged in series, and according to a voltage applied to the focus electrodes, a prefocus lens, a first and a second The present invention relates to an electron gun for cathode ray tubes in which dynamic quadrupole lenses are formed in series.

Referring to FIG. 1, the conventional color cathode ray tube 1 may be roughly classified into a panel 12, a funnel 13, an electron gun 20, and a deflection yoke 15. On the inner surface of the panel 12, a fluorescent film 11 in which each phosphor of red (R), green (G) and blue (B) is formed in a dot or stripe pattern is formed. The funnel 13 having the neck portion 13a and the cone portion 13b is sealed to the panel 12. The electron gun 11 is enclosed in the neck portion 13a of the funnel 13. The deflection yoke 15 is provided over the cone portion 13b of the funnel 13 to deflect the electron beam emitted from the electron gun 11.

The performance of this cathode ray tube 1 depends on the state in which the electron beams emitted from the electron gun 11 are landed on the fluorescent film 14. Therefore, in order for the electron beams emitted from the electron gun 11 to land accurately at the fluorescence point of the fluorescent film 14, many techniques have been developed that can improve the focus characteristic and reduce the aberration of the electron lens.

In particular, as the electron beams emitted from the electron gun are deflected by the deflection yoke, the electron beams emitted from the electron gun are horizontal and horizontal to prevent the ellipsoidal shape of the landing electron beams due to the difference in the barrel and pincushion magnetic field. A dynamic focus driving electron gun is used which is relatively elliptical in synchronization with the vertical deflection period.

In such an electron focus of the dynamic focus driving method, the problem that the distortion of the horizontal line in the periphery of the cathode ray tube becomes larger is increased. As a part of improving the problem, an electron gun for a cathode ray tube of a dual dynamic focus method is used.

2 shows a cathode ray tube driving apparatus according to a conventional dual dynamic focus driving method.

Referring to FIG. 2, the video signal processor 21 processes a complex video signal Sc input from the outside to output a horizontal sync signal, a vertical sync signal, a data signal, and a retrace signal.

The data signal including the luminance signals of red (R), green (G), and blue (B) is amplified by the data signal amplifier 27. The amplified data signal Sd is biased by the negative voltage from the first bias supply part 31 and applied to the cathode K of the electron gun 11.

The vertical deflection signal generator 22 generates a vertical deflection signal corresponding to the vertical synchronization signal from the video signal processor 21 and inputs it to the vertical deflection signal amplifier 24. In addition, the horizontal deflection signal generator 23 generates a horizontal deflection signal corresponding to the horizontal synchronization signal from the video signal processor 21 and inputs it to the horizontal deflection signal amplifier 25. The amplified vertical and horizontal deflection signals from the vertical and horizontal deflection signal amplifiers 24 and 25 are applied to the vertical and horizontal deflection yokes 15 of the cathode ray tube 1, respectively.

The horizontal / vertical retrace signal from the video signal processor 21 is amplified by the retrace signal amplifier 26. The horizontal / vertical retrace signal Sb from the retrace signal amplifier 26 is applied to the control electrode C of the electron gun 11. The heater power supply unit 36 supplies power to the heater of the cathode K of the electron gun 11. The second bias supply part 32 applies a positive screen voltage Vec to the screen electrode S and the second focus electrode F2 of the electron gun 11. The third bias supply part 33 applies the positive static focus voltage Vfs to the first, third and fifth focus electrodes F1, F3, and F5 of the electron gun 11. Here, the positive static focus voltage Vfs is higher than the positive screen voltage Vec for acceleration and focusing of the electron beam. The dynamic focus driver 35 applies the dynamic focus voltage Vfd to the fourth and sixth focus electrodes F4 and F6 periodically changing in the range above or below the static focus voltage Vfs, thereby providing an electron gun ( The electron beams emitted from 11) cause the electron beams to be relatively elliptical. The fourth bias driver 34 applies the highest anode voltage Veb to the final acceleration electrode A. FIG.

3 shows the internal structure of a conventional double dynamic focus type cathode ray tube electron gun. The electron gun of FIG. 3 has been filed in the Republic of Korea by the present applicant (Korean Patent Application No. 48541). In FIG. 3, the same reference numerals as used in FIG. 2 indicate objects of the same function. In FIG. 3, K _R denotes a red cathode, K _G denotes a green cathode, K _B denotes a blue cathode, S _dR denotes a red data signal, S _dG denotes a green data signal, and S _dB denotes a blue data signal. Point to each one. 4 shows the relationship between the driving voltages of the conventional dual dynamic focus method. In FIG. 4, T _h denotes a horizontal deflection period, V _pl denotes the lowest voltage of the dynamic focus voltage Vfd, and V _ph denotes the highest voltage of the dynamic focus voltage Vfd. 5A illustrates electron lenses in which the static focus voltage Vfs is formed at a time t1 to t3 higher than the dynamic focus voltage Vfd in the electron gun of FIG. 3. FIG. 5B illustrates electronic lenses in which the static focus voltage Vfs is lower than the dynamic focus voltage Vfd in the electron gun of FIG. 3 at times 0 to t1 and t3 to t4. 5A and 5B, reference numeral A _V denotes a vertical region in the electron gun, A _H denotes a horizontal region in the electron gun, P _B denotes a direction of movement of the electron beams, and F _V denotes a vertical region applied to the electron beams (A _V A vector of forces in), and F _H , respectively, indicate a vector of forces in the horizontal region A _H applied to the electron beams.

3, 4, 5A and 5B, each cathode K _R , K _G , K _B generates electron beams according to the corresponding data signal S _dR , S _dG , S _dB . Whether the generated electron beams are emitted is determined by the horizontal / vertical retrace signal Sb of the control electrode C. The electron beams emitted through the opening of the control electrode C are accelerated by the screen voltage Vec applied to the screen electrode S.

The static focus voltage Vfs applied to the first focus electrode F1 is higher than the screen voltage Vec applied to the screen electrode S. FIG. In addition, the shape of the outlet of the screen electrode S and the inlet of the first focus electrode F1 are the same circular shape, but the outlet of the screen electrode S is smaller. Therefore, a focusing lens is formed between the screen electrode S and the first focus electrode F1. In addition, an inlet of the first focus electrode F1 to which the static focus voltage Vfs is applied, an inlet and an outlet of the second focus electrode F2 to which the screen voltage Vec is applied, and a static focus voltage Vfs Since the entrance of the third focus electrode F3 to which the applied third is applied is the same circular shape, a prefocus lens (FIG. 5A or FIG. 5A) between the first, second and third focus electrodes F1, F2 and F3 is used. a focusing lens _(L S) as S _L) of 5b is formed. The focus of the beams emitted from the third focus electrode F3 is formed by the focusing lens S _L.

The exit of the third focus electrode F3 is horizontal, and the inlet of the fourth focus electrode F4 is elongated. The outlet of the fifth focus electrode F5 is elongated, and the inlet of the sixth focus electrode F6 is circular. The static focus voltage Vfs is applied to the third and fifth focus electrodes F3 and F5, and the dynamic focus voltage Vfd is applied to the fourth and sixth focus electrodes F3 and F5. An anode voltage Veb is applied to the final acceleration electrode A. FIG.

As a result, the following driving of the dual dynamic focus method is realized.

When the static focus voltage Vfs is lower than the dynamic focus voltage Vfd (0 to t1 and t3 to t4), the focusing lens in the vertical direction between the third and fourth focus electrodes F3 and F4 ( A first dynamic quadrupole lens is formed that performs the function of Q _L1V ) of FIG. 5B and a diverging lens (Q _L1H of FIG. 5B) in the horizontal direction. In addition, the fifth and sixth focus electrodes F5 and F6 perform the functions of the diverging lens in the vertical direction (Q _{L2V in} FIG. 5B) and the focusing lens in the horizontal direction (Q _{L2H in} FIG. 5B). Two dynamic quadrupole lenses are formed. The electron beams passing through the second dynamic quadrupole lens pass through the main lens M _L between the sixth focus electrode F6 and the final accelerating electrode A and are elliptical electron beams corresponding to the vertical and horizontal deflection voltages. Are emitted.

At a time t1 to t3 where the static focus voltage Vfs is higher than the dynamic focus voltage Vfd, the diverging lens in the vertical direction between the third and fourth focus electrodes F3 and F4 (Q in FIG. 5A). _L1V ) and a first dynamic quadrupole lens that performs the functions of the focusing lens (Q _{L1H in} FIG. 5A) in the horizontal direction. In addition, the fifth and sixth focus electrodes F5 and F6 perform the functions of the focusing lens Q _L2V in the vertical direction and the diverging lens Q _L2H in the horizontal direction in the vertical direction. Two dynamic quadrupole lenses are formed. The electron beams passing through the second dynamic quadrupole lens pass through the main lens M _L between the sixth focus electrode F6 and the final accelerating electrode A and are elliptical electron beams corresponding to the vertical and horizontal deflection voltages. Are emitted.

However, according to the conventional dual dynamic focus type cathode ray gun electron gun, the electron beams landing at the horizontal periphery of the screen are over-focused in the vertical and horizontal directions.

An object of the present invention, in the double-dynamic focus electron gun for the cathode ray tube, it is possible to prevent the phenomenon that the electron beams landing on the horizontal periphery of the screen is over-focused in the vertical and horizontal directions, it is possible to lower the dynamic focus voltage To provide an electron gun.

The present invention for achieving the above object, a plurality of focus electrodes are arranged in series, according to the voltage applied to the focus electrodes for the cathode ray tube tube is formed in series with the prefocus lens, the first and second dynamic quadrupole lenses It is an electron gun. In this electron gun, auxiliary dynamics performing the same lens function in the vertical and horizontal directions by having the same opening shape of the outgoing side focus electrode of the first dynamic lens and the incidence side focus electrode of the second dynamic lens are the same. The lens is formed. Here, the shape of the opening of the first dynamic lens facing the emission side focus electrode and the second dynamic lens facing the opening electrode is horizontal in the screen coordinate system of the cathode ray tube, whereby the magnification in the vertical direction of the auxiliary dynamic lens is horizontal. It is higher than magnification of direction.

According to the electron gun for the cathode ray tube of the present invention, the electron beams landing by the auxiliary dynamic lens to the horizontal periphery of the screen can enhance the force emitted in the vertical and horizontal directions, the electron beams landing in the horizontal center of the screen is vertical And the force focused in the horizontal direction. Accordingly, it is possible to prevent the electron beams landing at the horizontal periphery of the screen from being over-focused in the vertical and horizontal directions.

Preferably, since the opening shapes of the exiting focus electrode of the prefocus lens and the entrance focusing electrode of the first dynamic lens are the same and differ in size, they always have the same magnification in the vertical and horizontal directions. It is preferable that an auxiliary static lens is formed to perform the divergence function. Accordingly, the electron beams landing at the horizontal periphery of the screen can be more completely prevented from over-focusing in the vertical and horizontal directions, so that the dynamic focus voltage is increased to increase the magnification of the first and second dynamic quadrupole lenses. You do not have to set the high.

Hereinafter, preferred embodiments according to the present invention will be described in detail.

Figure 6 shows the internal structure of the electron gun for the cathode ray tube of the dual dynamic focus method according to an embodiment of the present invention. In FIG. 6, K _R is a red cathode, K _G is a green cathode, K _B is a blue cathode, S _dR is a red data signal, S _dG is a green data signal, and S _dB is a blue data signal. Point to each one. FIG. 7 shows electron lenses formed in the electron gun of FIG. 6. In FIG. 7, reference numeral A _V denotes a vertical region in the electron gun, A _H denotes a horizontal region in the electron gun, P _B denotes a direction of movement of the electron beams, and F _VP denotes a vertical applied to the electron beams to be landed at the periphery of the screen. The vector of force in the area A _V , the F _VM is the vector of force in the vertical area A _V applied to the electron beams to be landed at the center of the screen, and the F _HP is the electron to be landed at the periphery of the screen. The vector of force in the horizontal area A _H applied to the beams, and the F _HM respectively indicate the vector of force in the horizontal area A _H applied to the electron beams to be landing in the center of the screen.

6 and 7, according to the present invention, a plurality of focus electrodes F1 to F6 are arranged in series and according to voltages Vec, Vfs, and Vfd applied to the focus electrodes F1 to F6. It is an electron gun for cathode ray tubes in which a prefocus lens S _L and first and second dynamic quadrupole lenses are formed in series. In this electron gun, the opening-side focusing electrodes F4 of the first dynamic lens and the incidence opening shapes Outf ₄ and Inf ₅ of the incidence-side focus electrode F5 of the second dynamic lens are the same, so that the vertical and Secondary dynamic lenses SDL that perform the same lens functions with respect to the horizontal direction are formed.

According to such a cathode ray tube electron gun, the electron beams landing at the horizontal periphery of the screen by the auxiliary dynamic lens (SDL) can enhance the force emitted in the vertical and horizontal directions, and the electron beams landing at the horizontal center of the screen are vertical. And the force focused in the horizontal direction. Accordingly, it is possible to prevent the electron beams landing at the horizontal periphery of the screen from being over-focused in the vertical and horizontal directions.

Here, the opening shapes Outf ₄ and Inf ₅ of the emission side focus electrode F4 of the first dynamic lens and the incident side focus electrode F5 of the second dynamic lens are horizontal in the screen coordinate system of the cathode ray tube. As a result, the magnification in the vertical direction of the auxiliary dynamic lens SDL is higher than that in the horizontal direction. Accordingly, the phenomenon that the electron beams landing at the horizontal periphery of the screen can be more completely prevented from over-focusing in the vertical and horizontal directions.

Meanwhile, the facing openings Outf ₂ and Inf ₃ of the exit-side focus electrode F2 of the prefocus lens S _L and the entrance-side focus electrode F3 of the first dynamic lens are the same and differ in size. Thereby, the auxiliary static lens S _SL is formed which always performs the diverging function of the same magnification in the vertical and horizontal directions. Accordingly, the electron beams landing at the horizontal periphery of the screen can be more completely prevented from over-focusing in the vertical and horizontal directions, so that the dynamic focus voltage (i.e. It is not necessary to set Vfd) high.

6 and 7, the structure and operation of the cathode ray tube electron gun according to the present invention will be described in detail.

Each cathode K _R , K _G , K _B generates electron beams according to the corresponding data signal S _dR , S _dG , S _dB . Whether the generated electron beams are emitted is determined by the horizontal / vertical retrace signal Sb of the control electrode C. The electron beams emitted through the opening of the control electrode C are accelerated by the screen voltage Vec applied to the screen electrode S.

The static focus voltage Vfs applied to the first focus electrode F1 is higher than the screen voltage Vec applied to the screen electrode S. FIG. In addition, the shape of the outlet of the screen electrode S and the inlet of the first focus electrode F1 are the same circular shape, but the outlet of the screen electrode S is smaller. Therefore, a focusing lens is formed between the screen electrode S and the first focus electrode F1. In addition, an inlet of the first focus electrode F1 to which the static focus voltage Vfs is applied, an inlet and an outlet of the second focus electrode F2 to which the screen voltage Vec is applied, and a static focus voltage Vfs Since the entrance of the third focus electrode F3 to be applied is the same circular shape, the first, second and third focus electrodes F1, F2 and F3 may be used as a pre-focus lens S _L. A focusing lens S _L is formed. The focus of the beams emitted from the third focus electrode F3 is formed by the focusing lens S _L.

The facing shape of the second focusing electrode F2 and the third focusing electrode F3 is the same as the circular shape, but the outlet of the second focusing electrode F2 is wider than the inlet of the third focusing electrode F3. That is, the auxiliary static lens S _SL is formed which always performs the diverging function of the same magnification in the vertical and horizontal directions. Accordingly, the electron beams landing at the horizontal periphery of the screen can be more completely prevented from over-focusing in the vertical and horizontal directions, so that the dynamic focus voltage (i.e., the dynamic focus voltage) can be increased to increase the magnification of the first and second dynamic quadrupole lenses. Vfd) can be applied lower. A detailed analysis process will be described later.

The exit of the third focus electrode F3 is horizontal, and the inlet of the fourth focus electrode F4 is elongated. The outlet of the fourth focus electrode F4 and the inlet of the fifth focus electrode F5 have the same horizontal shape, but the outlet of the fourth focus electrode F4 is narrower than the inlet of the fifth focus electrode F5. The outlet of the fifth focus electrode F5 is elongated, and the inlet of the sixth focus electrode F6 is circular. The static focus voltage Vfs is applied to the third and fifth focus electrodes F3 and F5, and the dynamic focus voltage Vfd is applied to the fourth and sixth focus electrodes F3 and F5. An anode voltage Veb is applied to the final acceleration electrode A. FIG.

As a result, the following driving of the dual dynamic focus method is realized.

At a time when the static focus voltage Vfs is lower than the dynamic focus voltage Vfd (0 to t1 and t3 to t4 in FIG. 4), the static focus voltage Vfs is vertically interposed between the third and fourth focus electrodes F3 and F4. A first dynamic quadrupole lens is formed that performs the functions of the focusing lens Q _L1VP and the diverging lens Q _L1HP in the horizontal direction. In addition, the auxiliary dynamic lens SDL performing the functions of the auxiliary diverging lens SDL _VP in the vertical direction and the auxiliary diverging lens SDL _HP in the horizontal direction between the fourth and fifth focus electrodes F4 and F5. ) Is formed. In addition, a second dynamic quadrupole lens which functions as a diverging lens Q _L2VP in the vertical direction and a focusing lens Q _L2HP in the horizontal direction between the fifth and sixth focus electrodes F5 and F6 is provided. Is formed. The electron beams passing through the second dynamic quadrupole lens pass through the main lens M _L between the sixth focus electrode F6 and the final accelerating electrode A and are elliptical electron beams corresponding to the vertical and horizontal deflection voltages. Are emitted.

Here, by the auxiliary dynamic lens SDL, the phenomenon in which the electron beams landing at the horizontal periphery of the screen is over-focused in the vertical and horizontal directions can be prevented by the auxiliary dynamic lens SDL. In addition, the magnification in the vertical direction of the auxiliary dynamic lens SDL is higher than that in the horizontal direction. Accordingly, the phenomenon in which the electron beams landing at the horizontal periphery of the screen is over-focused in the vertical direction can be more completely prevented.

At the time when the static focus voltage Vfs is higher than the dynamic focus voltage Vfd (t1 to t3 in FIG. 4), the diverging lens Q in the vertical direction between the third and fourth focus electrodes F3 and F4. _L1VM ) and a first dynamic quadrupole lens that functions as a focusing lens Q _L1HM in the horizontal direction are formed. In addition, the auxiliary dynamic lens SDL performing the functions of the auxiliary focusing lens SDL _VM in the vertical direction and the auxiliary focusing lens SDL _HM in the horizontal direction between the fourth and fifth focus electrodes F4 and F5. ) Is formed. In addition, a second dynamic quadrupole lens which performs the functions of the focusing lens Q _L2VM in the vertical direction and the diverging lens Q _L2HM in the horizontal direction between the fifth and sixth focus electrodes F5 and F6 is provided. Is formed. The electron beams passing through the second dynamic quadrupole lens pass through the main lens M _L between the sixth focus electrode F6 and the final accelerating electrode A and are elliptical electron beams corresponding to the vertical and horizontal deflection voltages. Are emitted.

Here, by the auxiliary dynamic lens SDL, the phenomenon in which the electron beams landing in the horizontal center portion of the screen is under-focused in the vertical and horizontal directions can be prevented by the auxiliary dynamic lens SDL. In addition, the magnification in the vertical direction of the auxiliary dynamic lens SDL is higher than that in the horizontal direction. Accordingly, the phenomenon that the electron beams landing at the horizontal center portion of the screen is under-focused in the vertical direction can be more completely prevented.

On the other hand, the additional effect of the auxiliary static lens (S _SL ) will be verified by the equations.

Assuming that there is no auxiliary static lens S _SL , between the first and second quadrupole lenses at a time when the static focus voltage Vfs is higher than the dynamic focus voltage Vfd (t1 to t3 in FIG. 4). The total focusing force Fhm (total) for the horizontal area A _{H of} is calculated by Equation 1 below.

In the above Equation 1, Fhmq1 first dynamic home speed on the horizontal region (A _H) of the quadrupole lens, Fhmsd is the home speed on the horizontal region (A _H) of the secondary dynamic lens (SDL), and Fhmq2 Denotes the focusing force for the horizontal region A _H of the second dynamic quadrupole lens, respectively.

Assuming that there is no auxiliary static lens S _SL , between the first and second quadrupole lenses at a time when the static focus voltage Vfs is higher than the dynamic focus voltage Vfd (t1 to t3 in FIG. 4). The total focusing force Fvm (total) for the vertical region A _V of is obtained by Equation 2 below.

In the above Equation 2, Fvmq1 first dynamic home speed of the vertical area (A _V) of the quadrupole lens, Fvmsd is the home speed of the vertical area (A _V) of the secondary dynamic lens (SDL), and Fvmq2 Denotes the focusing force for the vertical region A _V of the second dynamic quadrupole lens, respectively.

In the above Equations 1 and 2, since the magnification of the second dynamic quadrupole lens is set higher than that of the first dynamic quadrupole lens, the total focusing force Fvm (total) for the vertical region A _V is the horizontal region ( It can be seen that it is stronger than the total focusing force Fhm (total) for A _H ). That is, assuming that there is no auxiliary static lens S _SL , the horizontal effect is greater than the lengthening effect at a time when the static focus voltage Vfs is higher than the dynamic focus voltage Vfd (t1 to t3 in FIG. 4). . Therefore, in order to apply the dynamic focus voltage Vfd lower, it is preferable to further reduce this horizontal effect applied to the center part of the screen.

Assuming that there is no auxiliary static lens S _SL , the first and second quadrupled at a time when the static focus voltage Vfs is lower than the dynamic focus voltage Vfd (0 to t1 and t3 to t4 in FIG. 4). The total focusing force Fhp (total) for the horizontal area A _H between the polar lenses is obtained by the following equation (3).

In the above Equation 3, Fhpq1 first dynamic home speed on the horizontal region (A _H) of the quadrupole lens, Fhpsd is the home speed on the horizontal region (A _H) of the secondary dynamic lens (SDL), and Fhpq2 Denotes the focusing force for the horizontal region A _H of the second dynamic quadrupole lens, respectively.

Assuming that there is no auxiliary static lens S _SL , the first and second quadrupled at a time when the static focus voltage Vfs is lower than the dynamic focus voltage Vfd (0 to t1 and t3 to t4 in FIG. 4). The total focusing force Fvp (total) for the vertical region A _V between the pole lenses is obtained by the following equation (4).

In the above Equation 4, Fvpq1 first dynamic home speed of the vertical area (A _V) of the quadrupole lens, Fvpsd is the home speed of the vertical area (A _V) of the secondary dynamic lens (SDL), and Fvpq2 Denotes the focusing force for the vertical region A _V of the second dynamic quadrupole lens, respectively.

In the above Equations 3 and 4, since the magnification of the second dynamic quadrupole lens is set higher than that of the first dynamic quadrupole lens, the total focusing force Fvp (total) for the vertical region A _V is the horizontal region ( It can be seen that it is weaker than the total focusing force Fhp (total) for A _H ). That is, when it is assumed that there is no auxiliary static lens S _SL , the horizontal effect is extended at a time when the static focus voltage Vfs is lower than the dynamic focus voltage Vfd (0 to t1 and t3 to t4 in FIG. 4). Smaller than the effect. However, in order to apply the dynamic focus voltage Vfd lower, it is desirable to further enlarge this horizontal effect applied to the periphery of the screen.

On the other hand, when the auxiliary static lens S _SL according to the present invention, the first and second at a time (t1 ~ t3 of Figure 4) when the static focus voltage (Vfs) is higher than the dynamic focus voltage (Vfd) The total focusing force Fhm '(total) for the horizontal area A _H between the quadrupole lenses is obtained by Equation 5 below.

In Equation 1, Fhmss indicates the focusing force on the horizontal area A _H of the auxiliary static lens S _SL .

When the auxiliary static lens S _SL according to the present invention is present, the first and second quadrupoles at a time when the static focus voltage Vfs is higher than the dynamic focus voltage Vfd (t1 to t3 in FIG. 4). The total focusing force Fvm '(total) for the vertical region A _V between the lenses is obtained by Equation 6 below.

In Equation 6 above, Fvmss indicates the focusing force for the vertical region A _V of the auxiliary static lens S _SL .

In the above Equations 5 and 6, since the magnification of the second dynamic quadrupole lens is set higher than that of the first dynamic quadrupole lens, the total focusing force Fvm '(total) with respect to the vertical region A _V is the horizontal region. It can be seen that it is stronger than the total focusing force Fhm '(total) for (A _H ). However, since the total focusing force Fvm '(total) for the vertical region A _V is weakened by the auxiliary static lens S _SL , the horizontal effect is also reduced. That is, by reducing the horizontal effect applied to the center of the screen, the dynamic focus voltage Vfd can be applied lower.

In addition, when the auxiliary static lens S _SL according to the present invention is present, the static focus voltage Vfs is lower than the dynamic focus voltage Vfd (0 to t1 and t3 to t4 in FIG. 4). The total focusing force Fhp '(total) for the horizontal area A _H between the first and second quadrupole lenses is obtained by Equation 7 below.

In Equation 1, Fhpss indicates the focusing force on the horizontal area A _H of the auxiliary static lens S _SL .

When the auxiliary static lens S _SL according to the present invention is present, the static focus voltage Vfs is lower than the dynamic focus voltage Vfd at a time low time (0 to t1 and t3 to t4 in FIG. 4). The total focusing force Fvp '(total) for the vertical region A _V between the first and second quadrupole lenses is obtained by Equation 8 below.

In Equation 6 above, Fvpss indicates the focusing force on the vertical region A _V of the auxiliary static lens S _SL .

In Equations 7 and 8, since the magnification of the second dynamic quadrupole lens is set higher than that of the first dynamic quadrupole lens, the total focusing force Fvp '(total) with respect to the vertical region A _V is the horizontal region. It can be seen that it is weaker than the total focusing force Fhp '(total) for (A _H ). Here, since the total focusing force Fvp '(total) for the vertical region A _V is weakened by the auxiliary static lens S _SL , the lengthening effect is relatively expanded. In other words, by extending this lengthening effect applied to the periphery of the screen, the dynamic focus voltage Vfd can be applied lower.

To confirm the above theoretical application, the anode voltage (Veb) of 32 kilovolts (KV), the anode current of 1.9 milliamps (mA) and 8.6 kilovolts for a 34-inch screen (640 x 480 mm) cathode ray tube The simulation results under the condition of the static focus voltage Vfs of (KV) are shown in Table 1 below.

   ODF2 (mm)    DH (mm)    DV (mm)     Vfd (V)       4.4     3.53    2.27     1,000       5.2     3.17    1.96       769       5.0     3.26    1.73       828     3.5 / 5.0     3.48    1.76       673

In Table 1 above, ODF2 indicates the diameter of the outlet (Outf2) of the second focus electrode (F2), DH and DV indicate the horizontal diameter and the vertical diameter for the beams landing in the center of the screen, respectively. 3.5 / 5.0 means that the horizontal maximum distance is 5.0 mm and the vertical maximum distance is 3.5 mm when the outlet Outf2 of the second focus electrode F2 has a horizontal key-groove shape. That is, it means that the auxiliary static lens S _SL performs a diverging function of different magnifications in the vertical and horizontal directions. Referring to Table 1 above, when the auxiliary static lens S _SL is formed because the outlet Outf2 of the second focus electrode F2 is relatively widened, the dynamic focus voltage Vfd may be lowered. In addition, it can be seen that the focusing performance can be improved.

8A is a graph showing the relationship of the vertical diameter D _SV to the dynamic focus voltage V _fd of one electron spot when constant vertical and horizontal deflection voltages are applied to the conventional electron gun of FIG. 3. 8B is a graph showing the relationship of the vertical diameter D _SV to the dynamic focus voltage V _fd of one electron spot when constant vertical and horizontal deflection voltages are applied to the electron gun according to the present invention of FIG. 6. Referring to FIGS. 8A and 8B, when constant vertical and horizontal deflection voltages are applied, the optimum change range of the vertical diameter D _SV with respect to the dynamic focus voltage V _fd of one electron spot is 2.0 to 5,0 millimeters ( mm). Therefore, according to the electron gun according to the present invention of FIG. 6, it can be seen that both the lowest voltage V _pl and the highest voltage V _{ph of the} dynamic focus voltage V _fd for obtaining the optimum variation range are lowered. In particular, it can be seen that the variable voltage Vpp of the dynamic focus voltage V _fd is lowered from the conventional 1,080 volts (V) to 780 volts (V) because the maximum voltage V _ph is significantly lowered.

As described above, according to the cathode ray tube electron gun according to the present invention, the electron beams landing at the horizontal periphery of the screen by the auxiliary dynamic lens can enhance the force emitted in the vertical and horizontal directions, Landing electron beams can weaken the force focused in the vertical and horizontal directions. Accordingly, it is possible to prevent the electron beams landing at the horizontal periphery of the screen from being over-focused in the vertical and horizontal directions.

The present invention is not limited to the above embodiments, but may be modified and improved by those skilled in the art within the spirit and scope of the invention as defined in the claims.

Claims (4)

In the electron gun for the cathode ray tube, a plurality of focus electrodes are arranged in series, the prefocus lens, the first and second dynamic quadrupole lenses are formed in series according to the voltage applied to the focus electrodes, By the same shape of the openings facing the exit-side focus electrode of the first dynamic lens and the incident-side focus electrode of the second dynamic lens, an auxiliary dynamic lens that performs the same lens function in the vertical and horizontal directions is formed. , Since the shape of the opening facing the emission side focus electrode of the first dynamic lens and the incident side focus electrode of the second dynamic lens is horizontal in the screen coordinate system of the cathode ray tube, the magnification in the vertical direction of the auxiliary dynamic lens is horizontal. Electron gun for cathode ray tube higher than magnification of direction. delete The method of claim 1, Since the shape of the openings facing the exit-side focus electrode of the prefocus lens and the entrance-side focus electrode of the first dynamic lens are the same and differ in size, the divergence function of the same magnification is always performed in the vertical and horizontal directions. An electron gun for a cathode ray tube in which an auxiliary static lens is formed. The method of claim 1, Divergence function of different magnifications in the vertical and horizontal directions at all times by having the same opening shape of the exiting focus electrode of the prefocus lens and the entrance focusing electrode of the first dynamic lens are the same and different in size Electron gun for the cathode ray tube is formed a secondary static lens to perform.

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