Abstract: A projection apparatus includes a discharge lamp; a control apparatus for controlling a discharge current through the lamp. The apparatus is designed in a first drive mode, to control the discharge current having an amplitude profile; in a second drive mode, to control the discharge current in accordance with the amplitude profile; and to change between the first mode and the second mode. The time difference between two changes is given by a first time interval, and the time difference between the change from the first mode to the second mode and a next instance of leaving the second mode is given by a second time interval. The apparatus further includes a control device to determine a first manipulated variable depending on a control deviation determined by the difference between a target voltage value and a measured voltage value, and to determine the first and/or the second time interval therefrom.

Abstract: A projection apparatus includes a discharge lamp; a control apparatus for controlling a discharge current through the lamp. The apparatus is designed in a first drive mode, to control the discharge current having an amplitude profile; in a second drive mode, to control the discharge current in accordance with the amplitude profile; and to change between the first mode and the second mode. The time difference between two changes is given by a first time interval, and the time difference between the change from the first mode to the second mode and a next instance of leaving the second mode is given by a second time interval. The apparatus further includes a control device to determine a first manipulated variable depending on a control deviation determined by the difference between a target voltage value and a measured voltage value, and to determine the first and/or the second time interval therefrom.

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.