A mirror device includes a frame body, a shaft member provided inside the frame body and connected to the frame body at both end portions, and a reflection member fixed to the shaft member and provided so as to be capable of swinging around an axis of the shaft member. The reflection member has a base portion provided along an axial direction of the shaft member and a reflection portion provided on the base portion. The base portion has a three-dimensional uneven structure including a bottom wall portion having a main surface provided along the axial direction of the shaft member and a plurality of side wall portions extending from the bottom wall portion on the side opposite to the reflection portion.

A variable focal length optical assembly may include a deformable entry lens element, a deformable first reflective element and a deformable second reflective element. Using a controller coupled to the deformable elements, an external force such as a mechanical, electrical, electromechanical, or electromagnetic force is applied to the deformable elements to provide any number of different focal lengths. Since the deformation of the deformable elements, and consequently the changes in focal length, occur much faster than the playback frame rate, a number of sub-frames, each containing an image obtained at a different focal length, are associated with each playback frame. The availability of multiple images in the form of sub-frames permits the selection of an optimal image for inclusion in the final playback frame sequence. The availability of multiple images in the form of sub-frames at different focal lengths also permits the seamless incorporation of zoom-in and zoom-out effects.

A beam delivery system according to an aspect of the present disclosure is used for an extreme ultraviolet light generation apparatus and includes a propagation mirror disposed on an optical path between a laser apparatus and a condensation optical system and configured to change the propagation direction of a pulse laser beam, and a curvature mirror disposed on an optical path between the propagation mirror and the condensation optical system and having a concave reflective surface configured to convert the pulse laser beam to be incident on the condensation optical system into a convergent beam. The curvature mirror has a focal length selected so that the beam spread angle of the pulse laser beam from the curvature mirror is constant irrespective of thermal deformation of the propagation mirror or constant with change in a predetermined allowable range irrespective of thermal deformation of the propagation mirror.

A display system includes a display screen, a light source to generate a light beam to be modulated in accordance with image data, and a beam scanning module to receive the light beams and to direct the light beam onto an associated display region of the display screen. The beam scanning module includes a resonant mirror configured to scan the light beam along a first scanning direction across the associated display region, and a linear scanning mirror to scan the light beam along a second scanning direction across the associated display region. The beam scanning module also includes an integral fold mirror positioned to reflect the light beam from the light source to the resonant mirror.

The disclosure belongs to the technical field of precision test and measurement, and provides a two-dimensional photoelectric autocollimation method and device based on wavefront measurement and correction. According to the disclosure, a link of wavefront measurement and correction of a reference light path is added to a traditional autocollimator measuring method. By using wavefront distortion information of the reference light path in the instrument and driving a deformable mirror to compensate for phase distortion of a beam, the link realizes measurement and control on aberration of the optical system of the autocollimator and improves the imaging quality and spot positioning accuracy of the optical system, thereby improving the angle measurement accuracy of the autocollimator. At the same time, by introducing the link, the autocollimator has the ability to resist interference from the external environment, so that the resolution and stability of angle measurement of the autocollimator are further improved. The method makes the traditional autocollimator have a nano-radian order (5×10.sup.−9 rad, that is 0.001″) angle resolution and a sub-microradian order (10.sup.−7 rad, that is 0.02″) angle measurement accuracy. The disclosure has the technical advantage of realizing angle measurement with high resolution, high accuracy and high stability under the same conditions, and has the abilities to resist environmental disturbances and compensate for errors caused by the disturbances.

A mirror including a substrate (110), a reflection layer system (120), and at least one continuous piezoelectric layer (130, . . . ) arranged between the substrate and the layer system. An electric field producing a locally variable deformation is applied to the piezoelectric layer via a first, layer-system-side electrode arrangement and a second, substrate-side electrode arrangement. At least one of the electrode arrangements is assigned a mediator layer (170) setting an at least regionally continuous profile of the electrical potential along the respective electrode arrangement. The electrode arrangement to which the mediator layer is assigned has a plurality of electrodes (160, . . . ), each of which is configured to receive an electrical voltage relative to the respective other electrode arrangement. In the region that couples two respectively adjacent electrodes, the mediator layer is subdivided into a plurality of regions (171, . . . ) that are electrically insulated from one another.

Several unique hardware configurations and methods for freeform optical display systems are disclosed. A freeform display system includes primary freeform optical element(s) and secondary freeform optical element(s) in tiled arrangements to expand the horizontal field of view (FOV) or the vertical field of view. The system may include a variable focusing system that produces intermediate pupil and changes the focal distance of a single focal plane or switches among multiple focal planes for rendering objects in focus while resolving accommodation-convergence conflict. The system may map light samples to appropriate light rays in physical space and use a cluster of projectors to project the mapped light rays to produce the light field of the virtual display content. Methods for making tiled freeform optical display systems and methods for producing virtual content with variable focus freeform optics and rendering light fields are also disclosed.

Method and apparatus for generating and controlling pulses in a light detection and ranging (LiDAR) system. An opto-mechanical phase shifter (OMPS) device has an array of unit cells supported by a semiconductor substrate. Each unit cell includes a resonator extending between opposing first and second doped regions and a flexible layer extending above the resonator separated by an intervening gap. Application of voltage across the doped regions establishes an electric field that extends through the resonator and controllably deforms the flexible layer to direct a beam of light in a desired direction and with a desired phase. A detector derives range information associated with a target illuminated by the directed beam of light. The derived range information can be used to adjust the voltage(s) applied to the OMPS device. Each unit cell can be independently activated and controlled, or groups of unit cells can be operated as a set.

A spherical aberration adjustment method for an objective optical system having an objective lens, and a diopter adjusting optical system arranged on an opposite side of a medium with respect to the objective lens, including changing an emittance or convergence of a luminous flux of laser light by the diopter adjusting optical system, and changing a depth of a focal point inside the medium with a diffraction limit of the objective optical system kept.

A device for thermally actuating a deformable mirror includes a monolithic block that includes a mirror plate having a front face forming or configured to support a mirror, a base, and a one-dimensional array of thermally expandable actuators. The thermally expandable actuators mechanically connect a rear face of the mirror plate to the base such that shape, tilt, and/or location of the front face depend on temperature of the thermally expandable actuators. The mirror plate, base, and thermally expandable actuators are defined by slits that span between opposite-facing top and bottom surfaces of the monolithic block. The monolithic block may be made of a metal and may be manufactured at relatively low cost by wire eroding the slits in a metal block, using a wire that passes through the metal block between its top and bottom surfaces.