Patent ID: 8879046

Claim:
An apparatus, comprising: an optical element; a manipulator configured to deflect the optical element in a degree of freedom, the manipulator comprising first and second actuators; and a control device configured to control the first and second actuators, wherein: the apparatus is a microlithography projection exposure apparatus; the first and second actuators are configured to deflect the optical element in a direction of the degree of freedom and in a direction counter to the direction of the degree of freedom; the first actuator is controllable by a first variable α 1 from a first control range [a 1 , b 1 ] with a minimum deflection of the optical element in the direction of the degree of freedom by the control in direction a 1 and with a maximum deflection of the optical element in the direction of the degree of freedom by the control in direction b 1 ; the second actuator is controllable by a second variable a 2 from a second control range [a 2 ,b 2 ] with a minimum deflection of the optical element in the direction of the degree of freedom by the control in direction a 2 and with a maximum deflection of the optical element in the direction of the degree of freedom by the control in direction b 2 ; the control device is configured to control the first and second actuators in the control ranges [a 1 , b 1 ] and [a 2 ,b 2 ], respectively; the manipulator comprises memory configured to hold a convolution parameter α where 0 < α < 1 2 ⁢ min ⁢ { b 1 - a 1 , b 2 - a 2 } ; and for all controls performed by the control device to control the optical element in the degree of freedom, the following conditions A to D hold true: A) If α 1 <a 1 +α then α 2 >b 2 −α and the first and second actuators jointly deflect the optical element; B) If α 1 >b 1 −α then α 2 <a 2 +α and the first and second actuators jointly deflect the optical element; C If a 1 +α 1 ≦b 1 −α the first actuator deflects the optical element; and D) If a 2 +α≦α 2 ≦b 2 −α the second actuator deflects the optical element.