A mirror, e.g. for a microlithographic projection exposure apparatus, includes an optical effective surface, a mirror substrate, a reflection layer stack for reflecting electromagnetic radiation incident on the optical effective surface, at least one first electrode arrangement, at least one second electrode arrangement, and an actuator layer system situated between the first and the second electrode arrangements. The actuator layer system is arranged between the mirror substrate and the reflection layer stack, has a piezoelectric layer, and reacts to an electrical voltage applied between the first and the second electrode arrangements with a deformation response in a direction perpendicular to the optical effective surface. The deformation response varies locally by at least 20% in PV value for a predefined electrical voltage that is spatially constant across the piezoelectric layer.

A variable focal length optical element including a light-transmitting layer, a cover, a gel, a piezoelectric film, and a driving electrode is provided. The cover has a first through hole to define a light-passing area. The cover, an adhesive layer, and the light-transmitting layer surround and form a first cavity together, and the gel is filled in the first cavity. The driving electrode is configured to drive the piezoelectric film, so that the piezoelectric film is deformed to pull the light-transmitting layer to bend and deform to squeeze the gel in the first cavity, and thereby controls a curvature change of an optical surface formed in the light-passing area by the gel protruding out from the first through hole.

Methods, systems and devices are disclosed to detect and compensate wavefront errors associated with light that spans a large range of wavelengths and different polarization states. One example system includes an optical wavefront sensor that is positioned to receive input light after propagation through a turbulent medium, such as air or water or other liquids, and to detect a wavefront error associated with at least one spectral component of the received light that has a plurality of spectral components. The system further includes a wavefront compensator that is positioned to receive the input light and to simultaneously effectuate wavefront corrections for the plurality of spectral components of the input light based on the detected wavefront error.

An optical imaging arrangement includes an optical element and a piezoelectric device. The optical element includes an optical element body carrying an optical surface on a front side of the optical element body. The piezoelectric device includes a first electrode and at least one piezoelectric element. The first electrode is configured to cooperate with the at least one piezoelectric element and at least one second electrode, when the at least one second electrode is located on a rear side of the optical element body and the at least one piezoelectric element is located between the first electrode and the at least one second electrode, the rear side of the optical element body being opposite to the front side of the optical element body. The first electrode is located on the front side of the optical element body, and the at least one piezoelectric element is formed by at least one piezoelectric section of the optical element body.

Various examples are provided related to amplified deformable mirrors (ADMs). In one embodiment, an ADM includes a deformable mirror and a flexible dielectric matrix deposited on a front side of the deformable mirror. A pathlength of a wavelength, λ.sub.0, of electromagnetic radiation passing through the dielectric matrix can be amplified by a distribution of dielectric particles embedded in the dielectric matrix.

The present embodiment relates to a prism actuator comprising: a housing; a holder having at least a part spaced apart from the housing; a prism disposed on the holder; a shape memory alloy member for connecting the housing and the holder to each other; and an elastic member for connecting the housing and the holder to each other, wherein the shape memory alloy member comprises first and second shape memory alloy members disposed on one side of the prism, the first shape memory alloy member connects an upper part of the holder and a lower part of the housing to each other, and the second shape memory alloy member connects a lower part of the holder and an upper part of the housing to each other.

A method for controlling a deformable mirror surface shape based on a radial primary function processes samples of a neural network training set, obtains elements of the neural network training set, characterizes the complex surface shape of the deformable mirror in each sample by using a radial primary function, takes characterization parameters of the surface shape in the each sample as an input of a neural network, and trains the neural network by taking a voltage of each piezoelectric ceramic corresponding to the complex surface shape as a corresponding output of the neural network. Training times of the neural network are consistent with a number of the samples. Finally, the trained neural network is obtained to verify the training effect of the neural network. According to the characterization parameters of the required surface, the neural network is used to control the deformable mirror to generate the required surface.

A projection exposure apparatus comprises a projection objective, and the projection objective comprises an optical device, wherein the optical device comprises an optical element having an optically effective surface and an electrostrictive actuator. The electrostrictive actuator is deformable by a control voltage being applied. The electrostrictive actuator is functionally connected to the optical element to influence the surface shape of the optically effective surface. A control device supplies the electrostrictive actuator with the control voltage. A measuring device is configured, at least at times while the electrostrictive actuator influences the optically effective surface of the optical element, to measure directly and/or to determine indirectly the temperature and/or a temperature change of the electrostrictive actuator and/or the surroundings thereof to take account of a temperature-dependent influence during driving of the electrostrictive actuator by the control device.

A field facet for a field facet mirror of a projection exposure apparatus has a reflection surface spanned by two field facet coordinates. An actuator device having at least two independently controllable actuator units serves to deform the reflection surface in at least two independent deformation degrees of freedom. A first of the deformation degrees of freedom brings about a change in a curvature of the reflection surface along a primary curvature coordinate which coincides with one of the field facet coordinates. A second of the deformation degrees of freedom brings about a change in a torsion of the reflection surface about the primary curvature coordinate. This can yield a field facet, the imaging performance of which is optimized, for example adapted to different illumination channel assignments within the projection exposure apparatus.

A deformable minor system comprising: a deformable mirror surface; a plurality of actuators coupled to the mirror surface to deform the minor surface; and a detector coupled to the actuators to detect, for each actuator, an output signal from a driver of the actuator; and a controller coupled to each of the plurality of actuators, wherein the controller is configured, for each actuator, to: add a test signal to an input signal to form a modified input signal; send the modified input signal to the actuator; receive an indication of the output signal from the driver; determine when a test signal portion of the output signal satisfies a threshold condition; and in response to the test signal portion satisfying the threshold condition, control a subset of adjacent actuators to execute a shutdown sequence.