The invention relates to a method for correcting a telecentricity error of an imaging device for semiconductor lithography having an illumination unit, an imaging optical unit, and a filter for correcting the telecentricity error, having the following method steps: determining the telecentricity error of the imaging device, designing a filter for correcting the telecentricity error, arranging the filter in the pupil plane of the illumination unit, determining the telecentricity error again, and repeating the method steps one to four until the telecentricity error falls below a specified telecentricity error.

The invention furthermore relates to an imaging device for semiconductor lithography, which is configured for carrying out the method.

The present disclosure relates to a filter unit, a filter selection method, and an imaging device that allow continuously changing a transmittance of an ND filter and switching between filters to be performed more easily. A disk provided with a plurality of filters including an ND filter having a continuously variable transmittance is rotated to cause a filter corresponding to a rotational orientation of the disk among the plurality of filters provided on the disk to be arranged on an optical axis of incident light toward an image sensor. The present disclosure can be applied to, for example, a filter unit, an imaging device, electronic equipment, a filter selection method, a program, or the like.

A heads-up display may comprise a viewing screen having a reflective surface; a housing defining an opening; a display element disposed within the housing and comprising an integral linear polarizer configured to polarize light in a first direction; and a first linear polarizer disposed between the display element and the viewing screen covering the opening defined by the housing configured to polarize light in the first direction. The display element may be capable of causing images to be displayed on the viewing screen.

In a general aspect, a structured optical beam with position-dependent polarizations is prepared for human observation. In some examples, an optics method includes processing an optical beam to produce a structured optical beam for human observation. Processing the optical beam includes receiving the optical beam from a laser source; attenuating the optical beam to an exposure irradiance level that is safe for direct viewing by a human eye; expanding the optical beam to a size configured for a field of view of the human eye; and preparing the optical beam with a position-dependent polarization profile. The structured optical beam, which has the position-dependent polarization profile, is directed towards an observation region for human observation.

An adaptive filter system and a method for controlling the adaptive filter system are described herein. The system can includes one or more filters to attenuate incoming light. The one or more filters can be moved by one or more actuators. The method can capture image data from an imaging device through the one or more filters. Information can be determined from the captured image data. The one or more filters can be moved to a position for capturing image data based on the information.

A head-up display includes: a display medium; a display that displays an image; and a projection optical system that forms a virtual image by guiding the image displayed by the display to the display medium. The projection optical system includes a first mirror disposed above the display and reflecting display light of the image. 3<α−(θ+φ)/2<11.7 is satisfied, where θ denotes an angle between a line segment connecting centers of the first mirror and the display and a normal line at the center of the first mirror, α denotes an angle between the line segment connecting the centers of the first mirror and the display and a normal line at the center of the display, and φ denotes an inclination angle at an edge of the first mirror closer to the display relative to the center of the first mirror.

The imaging apparatus includes an imaging element including an imaging surface on which light from a subject is incident, a first filter unit including an electronic first optical filter capable of changing a light transmittance, and a first drive mechanism that rotates the first filter unit about a first rotation center line between a first filtering position and a first retraction position. The first filtering position is a position where the first optical filter exists in front of the imaging surface of the imaging element and light before reaching the imaging surface passes through the first optical filter, and the first retraction position is a position where the first filter unit is out of the front of the imaging surface.

A three (or more) polarizer arrangement is used to demonstrate a wide-angle variable-neutral-density (VND) filter that has both contrast uniformity and color uniformity. According to one embodiment, the outer polarizers effectively counter-rotate with respect to a fixed center polarizer as a means of compensating for transmission non-uniformity associated with geometrical polarization distortions experienced by off-normal rays. In particular, the achromatic compensation arrangement enables angle uniformity relative to normal-incidence transmission when the number of stops of attenuation grows large (e.g. 10-stops, or OD3). The filters are useful for cameras or instrumentation allowing mechanical or electromechanical tuning.

A non-linear optical pumping detection apparatus and a non-linear optical absorption cross-section measurement method, which can simultaneously measure degenerate and non-degenerate two-photon absorption cross-section spectra. The measurement process is automatic, efficient and fast. The working wavelength band is from 380 nm to near infrared 1064 nm, and the non-linear performance measurement of the super-continuous wide spectra can be realized. A zoom optical system with a larger entrance pupil diameter is adopted as a weak signal acquisition lens. So the weak signal can be effectively extracted from background noise. Meanwhile, the mean square root diameter of an on-axis image point of the zoom optical system is 100 to 150 microns, the divergence angle 2α of the on-axis image point is 30.6 degrees, which well match the optical fiber coupling condition, thereby improving the coupling efficiency of the space light coupling into the optical fiber, and greatly improving the measurement sensitivity.

A head up display (HUD) system includes: one or more light sources and one or more phase modulators configured to generate and output a hologram; and a replicator configured to receive the hologram, to generate N replications of the hologram from the hologram, and to output the N replications of the hologram, where N is an integer greater than or equal to 2.