Abstract: An auto-focus system that includes (i) an illumination path that is configured to illuminate a sample with illumination beams that form multiple spot arrays on the sample that comprises an upstream set of spot arrays formed on a first side of an imaging area, and a downstream set of spot arrays formed on another side of the imaging area; (ii) a collection path that comprises an entrance pupil and is configured to collect collected beams that are emitted from the sample, and focus the collected beams along a first axis while imaging the entrance pupil along a second axis to provide optically processed beams. The sensor is configured to generate detection signals that represent the optically processed beams. The controller is configured to determine a focus state of an evaluation beam that impinges on imaging area.

Abstract: An optical system is described. The optical system comprises an input pupil for input of illumination radiation, and first and second field splitting stages. The first field splitting stage is configured to divide input illumination radiation into a first selected number of illumination beams along a selected first axis. The second field splitting stage is configured for receiving the first selected number of illumination beams and dividing said first selected number of illumination beam into a second selected number of illumination beams along a selected second axis. The optical system thus provides a selected number of illumination beams exiting through said output pupil and providing illumination of a region of a selected spatial shape.

Abstract: An auto-focus system that includes (a) an illumination path that is configured to illuminate a sample with illumination beams that form multiple spot arrays on the sample that includes an upstream set of spot arrays formed on a first side of an imaging area, and a downstream set of spot arrays formed on another side of the imaging area; (b) a mask that is located at an entrance pupil, the mask comprises a pair of off-axis slits for truncating each collected beam to provide a pair of rays per each collected beam; and (c) a splitter that includes (i) a first reflecting facet that is configured to direct to the first branch, first rays associated with the first collected beams, and (ii) a second reflecting facet that is oriented to the first reflecting facet and is configured to direct to the second branch, rays associated with the second collected beams; wherein the first reflecting facet and the second reflecting facet are located at a reflecting facets location that is outside an image plain, and is located i

Abstract: An auto-focus system that includes (a) an illumination path that is configured to illuminate a sample with illumination beams that form multiple spot arrays on the sample that comprises an upstream set of spot arrays formed on a first side of an imaging area, and a downstream set of spot arrays formed on another side of the imaging area; and (b) a collection path that includes (b.1) a first segment that comprises a first spherical telescope, a first field curvature compensator, a pair of first prisms, and a first collimated relay that consists essentially of a first relay input spherical lens and a first relay output spherical lens; (b.2) a second segment that comprises an second spherical telescope, an second field curvature compensator, a pair of second prisms, and an second collimated relay that consists essentially of a second relay input spherical lens and a second relay output spherical lens; and (b.3) a shared module.

Abstract: A method for auto-focusing by an auto-focus system, the method includes (a) illuminating a sample with illumination beams that form multiple spot arrays on the sample, wherein the spot arrays comprise an upstream set of spot arrays formed on a first side of an imaging area, and a downstream set of spot arrays formed on another side of the imaging area; (b) collecting collected beams emitted from the sample along a collection path that comprises an entrance pupil; (c) focusing the collected beams along a first axis while imaging the entrance pupil along a second axis to provide optically processed beams; (d) generating detection signals that represent the optically processed beams; and (e) determining a focus state of an evaluation beam that impinges on the imaging area.

Abstract: A method and a system for illuminating a substrate, the system may include an acousto-optic device (AOD); and an etendue expanding optical module. The AOD may include a surface having an illuminated region; wherein the illuminated region is configured to receive a collimated input beam while being fed with a control signal that causes the illuminated region to output illuminated region output beams that are collimated and exhibit deflection angles that scan, during a scan period, a deflection angular range. The etendue expanding optical module is configured to convert the illuminated region output beams to collimated output beams that impinge on an output aperture; wherein a collimated output beam has a width that exceeds a width of an illuminated region output beam; and wherein the etendue expanding optical module comprises a Dammann grating that is configured to output diffraction patterns, each diffraction pattern comprises diffraction orders that cover a continuous angular range.

Abstract: A method and a system for illuminating a substrate, the system may include an acousto-optic device (AOD); and an etendue expanding optical module. The AOD may include a surface having an illuminated region; wherein the illuminated region is configured to receive a collimated input beam while being fed with a control signal that causes the illuminated region to output illuminated region output beams that are collimated and exhibit deflection angles that scan, during a scan period, a deflection angular range. The etendue expanding optical module is configured to convert the illuminated region output beams to collimated output beams that impinge on an output aperture; wherein a collimated output beam has a width that exceeds a width of an illuminated region output beam; and wherein the etendue expanding optical module comprises a Dammann grating that is configured to output diffraction patterns, each diffraction pattern comprises diffraction orders that cover a continuous angular range.

Abstract: A method and a system for illuminating a substrate, the system may include an acousto-optic device (AOD); and an etendue expanding optical module. The AOD may include a surface having an illuminated region; wherein the illuminated region is configured to receive a collimated input beam while being fed with a control signal that causes the illuminated region to output illuminated region output beams that are collimated and exhibit deflection angles that scan, during a scan period, a deflection angular range. The etendue expanding optical module is configured to convert the illuminated region output beams to collimated output beams that impinge on an output aperture; wherein a collimated output beam has a width that exceeds a width of an illuminated region output beam; and wherein the etendue expanding optical module comprises a Dammann grating that is configured to output diffraction patterns, each diffraction pattern comprises diffraction orders that cover a continuous angular range.

Abstract: A method and a system for illuminating a substrate, the system may include an acousto-optic device (AOD); and an etendue expanding optical module. The AOD may include a surface having an illuminated region; wherein the illuminated region is configured to receive a collimated input beam while being fed with a control signal that causes the illuminated region to output illuminated region output beams that are collimated and exhibit deflection angles that scan, during a scan period, a deflection angular range. The etendue expanding optical module is configured to convert the illuminated region output beams to collimated output beams that impinge on an output aperture; wherein a collimated output beam has a width that exceeds a width of an illuminated region output beam; and wherein the etendue expanding optical module comprises a Dammann grating that is configured to output diffraction patterns, each diffraction pattern comprises diffraction orders that cover a continuous angular range.