Method for operating a projector having a high-pressure discharge lamp

• US 20120050351A1
• Filed: 05/15/2009
• Published: 03/01/2012
• Est. Priority Date: 05/15/2009
• Status: Abandoned Application

• Current Assignee: OSRAM Licht AG (Ams-Osram AG)
• Original Assignee: OSRAM Licht AG (Ams-Osram AG)
• Inventors: Huber, Andreas, Kroell, Josef, Schallmoser, Oskar, Dobler, Bastian
• Application Number:
  US13/319,522
• Publication Number:
  US 20120050351A1
• Time in Patent Office: Days
• US Class Current: 345/690
• CPC Class Codes: G03B 21/16 Cooling; Preventing overheating
• CPC Class Codes: G03B 21/2026 Gas discharge type light sources, e.g. arcs
• CPC Class Codes: G03B 21/2053 Intensity control of illuminating light controlled by video signal processing H04N5/74 or H04N9/31
• CPC Class Codes: G09G 2320/0646 Modulation of illumination source brightness and image signal correlated to each other
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: H04N 9/3155 for controlling the light source light source control per se H05B35/00 – H05B47/00; control of an illumination source for displays in general G09G3/3406
• CPC Class Codes: H05B 41/38 Controlling the intensity of light

Abstract

In various embodiments, a method for operating a projector having a high-pressure discharge lamp, wherein an intensity of a light emitted by the high-pressure discharge lamp depends upon an electrical power supplied to the high-pressure discharge lamp, may comprise providing image information to be projected and, depending on the image information, determining a nominal value for the intensity of the light, supplying electrical power to the high-pressure discharge lamp at least in dependence on the nominal value for the intensity, determining a value correlated with a temperature of the high-pressure discharge lamp, and supplying additional electrical power-depending on the value for the temperature.

Claims

1. A method for operating a projector having a high-pressure discharge lamp, wherein an intensity of a light emitted by the high-pressure discharge lamp depends upon an electrical power supplied to the high-pressure discharge lamp, comprising:

providing image information to be projected,

depending on the image information, determining a nominal value for the intensity of the light;

supplying electrical power to the high-pressure discharge lamp at least in dependence on the nominal value for the intensity,

determining a value correlated with a temperature of the high-pressure discharge lamp, and

supplying additional electrical power depending on the value for the temperature.

2. The method as claimed in claim 1, wherein more electrical power is supplied than obtained according to the nominal value for the intensity if the value for the temperature is lower than a prespecified minimum value.

3. The method as claimed in claim 1,

wherein the value for the temperature is calculated from power values each of which corresponds to an electrical power supplied to the high-pressure discharge lamp at a preceding point of time.

4. The method as claimed in claim 3,

wherein the value for the temperature is calculated from the power values by smoothing or by filtering with a low-pass filter (9).

5. The method as claimed in claim 1, wherein the amount of power supplied is changed within a prespecified period by a presettable value.

6. The method as claimed in claim 5,

wherein, at least for a part of the prespecified period, the changing is performed according to at least one of a ramp function or in a plurality of steps.

16. The method as claimed in claim 1, wherein less electrical power is supplied than obtained according to the nominal value for the intensity if the value for the temperature is higher than a prespecified maximum value.

7. A method for operating a projector having a high-pressure discharge lamp, wherein an intensity of a light emitted by the high-pressure discharge lamp depends upon an electrical power supplied to the high-pressure discharge, comprising:

providing image information to be projected,

determining, depending on the image information, a nominal value for the intensity of the light

supplying electrical power to the high-pressure discharge lamp at least in dependence on the nominal value for the intensity,

wherein a mean value for an electrical power supplied to the high-pressure discharge lamp in a preceding time interval is calculated and, depending on the calculated mean value, the electrical power is additionally supplied in accordance with a controller for adjusting the mean value to a nominal mean value.

8. The method for operating a projector having a high-pressure discharge lamp, wherein an intensity of a light emitted by the high-pressure discharge lamp depends upon an electrical power supplied to the high-pressure discharge, comprising:

providing image information to be projected,

determining a nominal value for the intensity of the light depending on the image information,

supplying electrical power to the high-pressure discharge lamp at least in dependence on the nominal value for the intensity,

wherein a future nominal value for an intensity to be provided at a prespecified future time point (t₀′

) intensity is determined and

prior to the future time point, a temperature of the high-pressure discharge lamp is changed in dependence on the future nominal value.

9. The method as claimed in claim 8,

wherein

a) the nominal value determined for the intensity is a future nominal value or

b) a future nominal value is estimated by means of a statistical evaluation of consecutive nominal values for the intensity.

10. The method as claimed in claim 8,

wherein the temperature is increased if the future nominal value falls below a presettable first threshold value, and/or the temperature is reduced if the future threshold value exceeds a presettable second threshold value.

11. The method as claimed in claim 8,

wherein, to change the temperature prior to the future time point, the high-pressure discharge lamp electrical power is additionally supplied in dependence on the future nominal value and wherein the light transmission or reflectance behavior of a transparent or reflecting display element of the projector, by means of which information can be displayed and which, for the projection of image information to be projected, is transilluminated or illuminated by the light of the high-pressure discharge lamp, is changed in dependence on the future nominal value.

12. The method as claimed in claim 8,

wherein, to change the temperature, a cooling capacity of a cooling device for the high-pressure discharge lamp is changed.

13. A projector having a high-pressure discharge lamp and a control unit,

configured to accept a nominal value for an intensity of a light emitted by the high-pressure discharge lamp and

to supply the high-pressure discharge lamp with electrical power at least in dependence on the nominal value,

wherein the control unit is configured

to determine a value corresponding to a temperature of the high-pressure discharge lamp and

to supply electrical power to the high-pressure discharge lamp depending on the value for the temperature.

14. The projector having a high-pressure discharge lamp and a control unit, configured

to accept a nominal value for an intensity of a light emitted by the high-pressure discharge lamp and

to supply electrical power to the high-pressure discharge lamp at least in dependence on the nominal value,

wherein the control unit is

further configured to calculate a mean value for an electrical power supplied to the high-pressure discharge lamp in a preceding time interval and

depending on the calculated mean value, to supply the electrical power in accordance with a controller for adjusting the mean value to a nominal mean value.

15. The projector having a high-pressure discharge lamp and a control unit,

configured to accept a nominal value for an intensity of a light emitted by the high-pressure discharge lamp and

to supply electrical power to the high-pressure discharge lamp at least in dependence on the nominal value,

wherein the control unit is additionally designed

to determine a future nominal value for an intensity to provide at a prespecified future time point and

prior to the future time point, to change a temperature of the high-pressure discharge lamp in dependence on the future nominal value.