Subpixel rendering for cathode ray tube devices

1. A cathode ray tube (CRT) device comprising:

a plurality of electron guns to produce a plurality of electron beams;

a plurality of separate phosphor dots each corresponding to the one of a plurality of primary colors; certain ones of the plurality of phosphor dots forming a color spot of a single primary color when impacted by one of the electron beams; the plurality of said color spots of said single primary color forming a primary color plane; and

steering electronics coupled to the plurality of electron guns to guide the electron beams to project on the plurality of separate phosphor dots to form a plurality of color spots each indicating a different one of the plurality of primary colors, the steering electronics directing the electron beams to separate and shift the plurality of the color spots forming a first primary color plane indicating one of the primary colors from the plurality of the color spots forming a second primary color plane indicating a different one of the primary colors such that the first primary color plane is partially offset in two dimensions from a converged position with respect to the second primary color plane.

2. The CRT device of claim 1 , further comprising:

a subpixel clock coupled to the steering electronics to effect subpixel rendering.

3. The CRT device of claim 1 , wherein timing of producing the color spots is switched between odd and even rows, and wherein during the odd row, the color spots of the first primary color plane lead the color spots of the second primary color plane, and during the even row, the color spots of the second primary color plane lead the color spots of the first primary color plane.

4. The CRT device of claim 1 , wherein the first primary color plane is offset from the second primary color plane in a diagonal direction.

5. The CRT device of claim 1 , wherein the first primary color plane is offset in two dimensions from the second primary color plane in a range of 50% to 75% from a converged position.

6. The CRT device of claim 2 , wherein the plurality of primary colors includes red, green and blue colors, the plurality of single primary color spots respectively forming red, green and blue color planes, wherein the subpixel clock operates at three times the rate of a pixel clock; and wherein the red color plane leads the green color plane by one third of a pixel clock, and the green color plane leads the blue color plane by two thirds of a pixel clock.

7. The CRT device of claim 4 , wherein the first primary color plane is offset from the second primary color plane in a diagonal direction by one-half pixel.

8. A method of operating a cathode ray tube (CRT) device, the method comprising:

producing a plurality of electron beams directed to a plurality of separate phosphor dots each corresponding to one of a plurality of primary colors; certain ones of the plurality of phosphor dots forming a color spot of a single primary color when impacted by one of the electron beams; the plurality of said color spots of said single primary color forming a primary color plane; and

steering the electron beams to the plurality of separate phosphor dots to form a plurality of color spots each indicating a different one of the plurality of primary colors; steering the electron beams further comprising directing the electron beams to separate and shift the plurality of the color spots forming a first primary color plane indicating one of the primary colors from the plurality of the colors spots forming a second primary color plane indicating a different one of the primary colors such that the first primary color plane is partially offset from a converged position with respect to the second primary color plane.

9. The method of claim 8 , further comprising:

effecting subpixel rendering.

10. The method of claim 8 , wherein directing the electron beams causes the first primary color plane to be offset from the second primary color plane in a diagonal direction.

11. The method of claim 8 , wherein steering the electron beams to the plurality of separate phosphor dots further comprises temporally switching producing the first and second primary color planes between odd and even rows such that during the odd row, the color spots of the first primary color plane lead the color spots of the second primary color plane, and during the even row, the color spots of the second primary color plane lead the color spots of the first primary color plane.

12. The method of claim 8 , wherein the plurality of primary colors includes red, green and blue colors, the plurality of single primary color spots respectively forming red, green and blue color planes; and wherein steering the electron beams to the plurality of separate phosphor dots further comprises using a subpixel clock operating at three times the rate of a pixel clock to cause the red color plane to lead the green color plane by one third of a pixel clock, and to cause the green color plane to lead the blue color plane by two thirds of a pixel clock.

13. The method of claim 8 wherein directing the electron beams causes the first primary color plane to be offset in two dimensions from the second primary color plane in a range of 50% to 75% from a converged position.

14. The method of claim 10 , wherein the first primary color plane is a green color plane; and wherein directing the electron beams causes the green primary color plane to be diagonally offset from the second primary color plane.

15. The method of claim 14 , wherein directing the electron beams causes the green primary color plane to be diagonally offset from converged red and blue primary color planes.

16. The method of claim 10 , wherein directing the electron beams causes the first primary color plane to be offset from the second primary color plane in a diagonal direction by one-half pixel.