Patent ID: 9436072
Filing Date: 2016-09-06
CPC Classification: G02B,G03B,H04N,H05B

Claim Text:
1. A method for determining a predefinable wave form of a lamp current for operating a discharge lamp of a projection arrangement in at least one first operating mode, wherein the projection arrangement has a predefined rotatable color wheel and the discharge lamp for illuminating the color wheel, wherein the discharge lamp has two electrodes, wherein the projection arrangement has a ballast for the discharge lamp, which ballast, during the operation of the projection arrangement, provides for the discharge lamp a lamp current embodied as alternating current and having the predefinable wave form, which has a predefinable commutation scheme, such that a polarity of the electrodes is commutated in accordance with the predefinable commutation scheme, the method comprising: providing at least one first wave form having a first commutation scheme; checking whether operation of the discharge lamp with a lamp current having the at least one first wave form satisfies one criterion of two criteria, wherein one of the two criteria relates to a lifetime of the discharge lamp and one of the two criteria relates to a flicker amplitude of the projection arrangement; if the one criterion is satisfied, checking whether operation of the discharge lamp with a lamp current having the at least one first wave form satisfies a further criterion of the two criteria; and if at least the one criterion and the further criterion are satisfied, storing the at least one first wave form in a memory of the projection arrangement and providing the at least one first wave form as the predefinable wave form at the ballast for the discharge lamp.