A projection optical unit images an object field in an image field. The projection optical unit includes a plurality of mirrors guides imaging light from the object field to the image field. At least two of the mirrors are arranged directly behind one another in the beam path of the imaging light for grazing incidence with an angle of incidence of the imaging light which is greater than 60. This results in an imaging optical unit that can exhibit a well-corrected imageable field with, at the same time, a high imaging light throughput.

A projection optical unit for EUV projection lithography has a plurality of mirrors for imaging an object field into an image field with illumination light. At least one of the mirrors is an NI mirror and at least one of the mirrors is a GI mirror. A mirror dimension Dx of the at least one NI mirror in a plane of extent (xz) perpendicular to a plane of incidence (yz) satisfies the following relationship:
4 LLWx/IWPV.sub.max<Dx. A mirror dimension Dy of the at least one GI mirror in the plane of incidence (yz) satisfies the following relationship:
4 LLWy/(IWPV.sub.max cos(a))<Dy.

An optical system (L0) that forms an image of an object and that includes an aperture stop (SP), a first reflection surface (R2), and a second reflection surface (R3) which are disposed in order from an enlargement side to a reduction side, an area of the first reflection surface is larger than an area of the second reflection surface, a reference axis is a path of a reference ray that passes through an opening center of the aperture stop to reach a center of a reduction plane, and an angle QPR (deg) between a line segment PQ connecting the opening center P and an intersection Q of the reference axis and the first reflection surface, and a line segment PR connecting the opening center P and an intersection R of the reference axis and the second reflection surface satisfies a predetermined condition.

An optical relay system includes four or more reflective optical elements oriented in a tilted configuration. Each of the four or more reflective optical elements is tilted about one of four or more tilt axes. Further, the four or more tilt axes are oriented to correct for aberrations induced by the tilted configuration.

An imaging optical unit for projection lithography has a plurality of mirrors for imaging an object field into an image field with imaging light guided along a path from the object field to the image field. The penultimate mirror in the path has no passage opening to pass the imaging light. The imaging optical unit has a stop to predefine an outer marginal contour of a pupil of the imaging optical unit. The stop is between the penultimate and last mirrors in the path. The imaging optical unit can have exactly one stop for predefining at least one section of the outer pupil marginal contour. An entrance pupil of the imaging optical unit can be upstream of the object field. The imaging optical unit can be well defined regarding its pupil and exhibit desirable properties for projection lithography.

An imaging optical unit comprises a plurality of minors for imaging an object field into an image field. The imaging optical unit has an image-side numerical aperture greater than 0.55. Each mirror is configured so that it can be measured by a testing optical unit having at least one DOE with a predetermined maximum diameter for test wavefront generation. For the complete measurement of all reflection surfaces of the minors, a maximum number of DOEs of the testing optical unit and/or a maximum number of DOE test positions of the at least one DOE of the testing optical unit comes into play, which is no more than five times the number of minors in the imaging optical unit. The result is an imaging optical unit in which a testing-optical measurement remains manageable even in the case of a design with an image-side numerical aperture which is relatively large.

An imaging optical unit comprises a plurality of mirrors for imaging an object field in an object plane into an image field in an image plane. An image-side numerical aperture is greater than 0.55. A ratio between an object/image offset and a meridional transverse direction is at least 0.5. A ratio between a working distance between the object plane and a reflection portion, closest to the object plane, of one of the mirrors and the meridional transverse dimension is at least 0.05. The working distance is at least 270 mm. This can yield an imaging optical unit, the use of which is relatively manageable in a projection exposure apparatus, such as for EUV projection lithography.

A catoptric system having a reference axis and first, second, and third reflectors. The first reflector contains a pattern-source carrying a substantially one-dimensional pattern. A combination of the second and third reflectors is configured to form an optical image of the pattern, with a demagnification coefficient N>1 in extreme UV light, and with only two beams of light that have originated at the first reflector as a result of irradiation of the first reflector with light incident upon it. An exposure apparatus employing the catoptric system and method of device manufacturing with the use of the exposure apparatus.

An coronagraph optical system and method for continuously imaging a wide field of view that includes the Sun. Examples of the coronagraph optical system include an all-reflective foreoptics assembly that receives light rays from a viewed scene and a direct solar image of the Sun, a sensor assembly configured to produce an image of the viewed scene, an all-reflective relay optics assembly configured to receive the light rays from the foreoptics assembly and to reflect the light rays to the sensor assembly, and a solar rejection optical component positioned between the foreoptics assembly and the relay optics assembly and dynamically configurable such that the direct solar image of the Sun is reflected away from the relay optics assembly and the light rays are reflected to the relay optics assembly while an entrance aperture of the foreoptics assembly is continuously positioned towards the Sun.

An apparatus includes a wavefront sensor configured to receive coherent flood illumination that is reflected from a remote object and to estimate wavefront errors associated with the coherent flood illumination. The apparatus also includes a beam director optically coupled to the wavefront sensor and having a telescope and an auto-alignment system. The auto-alignment system is configured to adjust at least one first optical device in order to alter a line-of-sight of the wavefront sensor. The wavefront errors estimated by the wavefront sensor include a wavefront error resulting from the adjustment of the at least one first optical device. The beam director could further include at least one second optical device configured to correct for the wavefront errors. The at least one second optical device could include at least one deformable mirror.