1. An aqueous dispersion comprising an alkali-doped silica, wherein said silica is produced pyrogenically while being doped with an alkali containing aerosol,
said silica having an average particle diameter of secondary particles of less than 100 nm and a ratio dnda of an arithmetic mean of a number distribution dn and an arithmetic mean of a surface distribution da of primary particles of at least 0.7.
2. The aqueous dispersion according to claim 1, wherein the alkali content of the doped silica is from 10 ppm to 10 wt. %
3. The aqueous dispersion according to claim 1, wherein a BET surface of the alkali-doped silica is from 5 to 600 m2g.
4. The aqueous dispersion according to claim 1, wherein a solids content is from 0.1 wt. % to 70 wt. %.
5. The aqueous dispersion according to claim 1, wherein the dispersion has a pH from 8 to 12.
6. The aqueous dispersion according to claim 1, wherein the silica is doped with an aerosol comprising potassium.
7. A process for preparing the aqueous dispersion according to claim 1, comprising dispersing the alkali doped silica in an aqueous solution.
8. The process as claimed in claim 7, wherein the silica is dispersed in an aqueous solution by means of high energy input.
9. The process as claimed in claim 7, wherein the silica is dispersed in an aqueous solution with a planetary kneadermixer.
10. The process according to claim 7, further comprising:
pressurizing the alkali-doped silica under a pressure at up to 3500 Kgcm3,
pressurizing an aqueous solvent under a pressure of up to 3500 Kgcm3, and
depressurizing the alkali-doped silica and the aqueous solvent,
wherein said depressurized alkali-doped silica and said depressurized aqueous solvent may collide with each other or a wall of a reaction device.
11. A method for planarizing a semiconductor substrate or one or more layers applied thereto, comprising polishing said substrate or said one or more layers with the aqueous dispersion claimed in claim 1.
12. A paper of surface coating produced with the aqueous dispersion claimed in claim 1.
13. A cosmetic filler or glass component produced with the aqueous dispersion as claimed in claim 1.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A display apparatus comprising a display panel, a light source unit, an illumination unit to illuminate the display panel with light emitted from the light source unit, and a projection unit to project the light from the display panel in a predetermined direction, the display apparatus comprising:
a light sensor which is provided between the light source unit and the illumination unit; and
a light controller which corrects brightness of light sensed by the light sensor on the basis of reflective characteristics of the display panel.
2. The display apparatus according to claim 1, wherein the light controller excludes the brightness of the light reflected from the display panel to the illumination unit from the brightness of the sensed light.
3. The display apparatus according to claim 2, wherein the display panel comprise a digital micro-mirror device (DMD) having a plurality of pixels, and
the light controller comprises a storage that stores the brightness of the light reflected from the display panel to the illumination unit in correspondence to the number of pixels to be turned on.
4. The display apparatus according to claim 2, wherein the display panel comprise a digital micro-mirror device (DMD) having a plurality of pixels, and
the light controller calculates the brightness of the light reflected from the display panel to the illumination unit in correspondence to the number of pixels to be turned on, through a predetermined function.
5. The display apparatus according to claim 1, wherein the light source unit comprises a plurality of light sources that emit light having different colors, and
the display apparatus further comprising a light source driver to supply driving power to the light source unit to emit light having different colors in sequence according to predetermined periods.
6. The display apparatus according to claim 5, wherein the light sensor outputs a sensed voltage corresponding to the sensed light, and
the light controller comprises an operation amplifier to which the sensed voltage and a reference voltage of which level is adjusted by a pulse width modulation (PWM) signal corresponding to the driving power are input, and determines a duty ratio of the PWM signal corresponding to the sensed voltage on the basis of an output signal from the operation amplifier.
7. The display apparatus according to claim 1, wherein the light sensor comprises a signal converter to convert the brightness of the sensed light into a digital signal.
8. The display apparatus according to claim 1, wherein the light controller adjusts at least one of a white balance and a color temperature of the light to be offered to the display panel on the basis of the correct brightness of the light.
9. A display apparatus comprising a display panel, a light source unit, an illumination unit to illuminate the display panel with light emitted from the light source unit, and a projection unit to project the light from the display panel in a predetermined direction, the display apparatus comprising:
a light sensor which is provided between the light source unit and the illumination unit; and
a light controller which determines brightness of light emitted from the illumination unit to the display panel on the basis of brightness of light sensed by the light sensor and the brightness of light reflected from the display panel to the illumination unit, and adjusts at least one of a white balance and a color temperature of the light emitted from the illumination unit to the display panel on the basis of the determined brightness of the light.
10. The display apparatus according to claim 9, wherein the display panel comprise a digital micro-mirror device (DMD) having a plurality of pixels, and
the light controller comprises a lookup table that stores the brightness of the light reflected from the display panel to the illumination unit in correspondence to the number of pixels to be turned on.
11. The display apparatus according to claim 9, wherein the display panel comprise a digital micro-mirror device (DMD) having a plurality of pixels, and
the light controller calculates the brightness of the light reflected from the display panel to the illumination unit in correspondence to the number of pixels to be turned on, through a predetermined function.
12. A method of control a display apparatus comprising a display panel, a light source unit, an illumination unit to illuminate the display panel with light emitted from the light source unit, and a projection unit to project the light from the display panel in a predetermined direction, the method comprising:
providing the display panel with the light;
sensing the light through the light sensor; and
correcting the brightness of the sensed light on the basis of reflective characteristics of the display panel.
13. The method according to claim 12, wherein the correction of the brightness of the light comprises excluding the brightness of the light reflected from the display panel to the illumination unit from the brightness of the sensed light.
14. The method according to claim 12, wherein the display panel comprise a digital micro-mirror device (DMD) having a plurality of pixels, and
the correction of the brightness of the light comprises calculating the brightness of the light reflected from the display panel to the illumination unit in correspondence to the number of pixels to be turned on, and subtracting the calculated brightness of the light from the brightness of the sensed light.
15. The method according to claim 12, further comprising adjusting at least one of a white balance and a color temperature of light to be offered to the display panel on the basis of the correct brightness of the light.
16. The method according to claim 12, wherein the correction of the brightness of the light comprises calculating the brightness of the light reflected from the display panel to the illumination unit in correspondence to the number of pixels to be turned on, and subtracting the calculated brightness of the reflected light from the brightness of the sensed light.
17. The method according to claim 12, wherein the correction of the brightness of the light comprises subtracting a stored brightness value of the light reflected from the display panel to the illumination unit, the stored brightness value corresponding to the number of pixels which are turned on.
18. The method according to claim 12, wherein the reflective characteristics of the display panel is a number of pixels that are turned on.
19. The method according to claim 12, wherein the reflective characteristics of the display panel is the type of the display panel.
20. The method according to claim 12, wherein the reflective characteristics of the display panel is the deterioration state of the display panel.
21. The method according to claim 12, wherein sensing of the light from the light source occurs before the light is transmitted through the illumination unit.
22. The method according to claim 12, wherein sensing of the light from the light source occurs after the light is transmitted through the illumination unit.
23. A method of control a display apparatus comprising a display panel, a light source unit, an illumination unit to illuminate the display panel with light emitted from the light source unit, and a projection unit to project the light from the display panel in a predetermined direction, the method comprising:
providing the display panel with the light;
sensing the light through the light sensor; and
correcting the brightness of the sensed light on the basis of number of the pixels of the display panel that are turned on.
24. The method according to claim 23, wherein the correcting the brightness occurs by subtracting the value corresponding to the reflected light from the display panel.
25. The method according to claim 23, further comprising the step of:
controlling the intensity of the light from the light source unit based upon the corrected brightness.
26. The method according to claim 24, wherein the display panel is a DMD.
27. The method according to claim 23, wherein the light sensor is a photo diode.
28. The method according to claim 23, wherein the light source unit is an LED device.
29. A method of control a display apparatus comprising a display panel and a light source unit in which the light emitted from the light source unit is directed at the display panel, the method comprising:
providing the display panel with the light;
sensing the light through the light sensor; and
correcting the brightness of the sensed light on the basis of number of the pixels of the display panel that are turned on.
30. The method according to claim 29, wherein the correcting the brightness occurs by subtracting the value corresponding to the reflected light from the display panel.
31. The method according to claim 23, further comprising the step of:
controlling the intensity of the light from the light source unit based upon the corrected brightness.