An image sensor includes: a sensor substrate including a plurality of first pixels and a plurality of second pixels; a spacer layer on the sensor substrate; and a color separating lens array on the spacer layer and changing condensing light of a first wavelength on each of the first pixels and condensing light of a second wavelength on each of the second pixels. The color separating lens array includes a first color separating lens array layer including a plurality of first nanoposts, a first dielectric material layer arranged among the plurality of first nanoposts, and a plurality of first etch prevention patterns arranged respectively under the plurality of first nanoposts.

The invention provides a projection device including a first display, a second display, a third display, a light-combining module, a first angle selector, a second angle selector, a third angle selector, and a projection lens. The first display, the second display, and the third display are respectively adapted to provide a first image beam, a second image beam, and a third image beam. The projection lens is configured on one side of a light-outgoing surface of the light-combining module, and is adapted to project the first image beam, the second image beam, and the third image beam out of the projection device. The first image beam, the second image beam, and the third image beam respectively pass through the first angle selector, the second angle selector, and the third angle selector, and are then transmitted to the projection lens by the light-combining module.

A laser apparatus including an optical element made of a CaF.sub.2 crystal and configured to transmit an ultraviolet laser beam obliquely incident on one surface of the optical element, the electric field axis of the P-polarized component of the laser beam propagating through the optical element coinciding with one axis contained in <111> of the CaF.sub.2 crystal, with the P-polarized component defined with respect to the one surface. A method for manufacturing an optical element, the method including causing a seed CaF.sub.2 crystal to undergo crystal growth along one axis contained in <111> to form an ingot, setting a cutting axis to be an axis inclining by an angle within 14.18±5° with respect to the crystal growth direction toward the direction of another axis contained in <111>, which differs from the crystal growth direction, and cutting the ingot along a plane perpendicular to the cutting axis.

An optical substrate has a structured surface that enhances brightness and reduces moire effect. The optical substrate has a three-dimensionally varying, structured light output surface that comprises an irregular prismatic structure. The irregular prismatic structure may be viewed as comprising longitudinal prism blocks or rows thereof, arranged laterally defining peaks and valleys. Adjacent peaks, adjacent valleys, and/or adjacent peak and valley may be parallel or non-parallel, in an orderly, semi-orderly, random, or quasi-random manner. The lateral adjacent peaks, adjacent valleys, and/or adjacent peak and valley are not parallel. The adjacent irregular prism blocks may be irregular longitudinal sections having the same length, or random or quasi-random irregular sections having different lengths. The facets of each prism block may be flat, or curved (convexly and/or concavely).

Disclosed herein is a scanning ladar transmitter that employs an optical field splitter/inverter to improve the gaze characteristics of the ladar transmitter on desirable portions of a scan area. Also disclosed is the use of scan patterns such as Lissajous scan patterns for a scanning ladar transmitter where a phase drift is induced into the scanning to improve the gaze characteristics of the ladar transmitter on desirable portions of the scan area. Also disclosed is a compact beam scanner assembly that includes an ellipsoidal reimaging mirror.

The illumination optical system is capable of reducing, without moving any optical member and without causing flicker when displaying a still image, sample-and-hold blur when displaying a moving image. The illumination optical system (20) respectively guides multiple light fluxes (Li, Lii, Liii) from multiple light sources (i, ii, iii) in a light source unit (10) to multiple illumination regions (4a, 4b, 4c) on an illumination surface (4). The illumination optical system includes an integrator optical system (1, 2) located between the light source unit and the illumination surface. The integrator optical system includes a first lens array (1) and a second lens array (2) each including multiple lens cells in order from a light source unit side. The illumination optical system changes illumination states of the multiple illumination regions depending on changes of states of the light sources.

A projector includes a light source, a digital micro-mirror device (DMD), a first prism, a second prism, and a lens. The light source is used for emitting an incident light. The DMD is used for receiving and reflecting the incident light as an image light. The first prism is disposed between the light source and the DMD. The second prism is disposed between the first prism and the DMD. The first prism includes a first plane, a second plane, and an intermediate portion. The intermediate portion adjoins the first plane and includes a reflecting portion. The incident light from the second plane is reflected by the reflecting portion and then passes through the second plane. The second prism includes a fourth plane, a fifth plane, and a sixth plane. When the DMD is operated in an on-state, the image light passes through the sixth plane.

The laser system may include first and second laser apparatuses and a beam delivery device. The first laser apparatus may be provided so as to emit a first laser beam to the beam delivery device in a first direction. The second laser apparatus may be provided so as to emit a second laser beam to the beam delivery device in a direction substantially parallel to the first direction. The beam delivery device may be configured to bundle the first and second laser beams and to emit the first and second laser beams from the beam delivery device to a beam delivery direction different from the first direction.

A laser array comprises first and second laser unit to respectively emit a first and second laser beams that propagate in a first and second directions and that are polarized in first and second polarization directions and a polarization coupling prism arranged to couple the two laser beams. The coupling prism comprises: a light entry surface to receive the first laser beam; a reflecting surface to reflect the first laser beam at an angle greater than the limit angle of total inner reflection; and a light exit surface through which the first laser beam exits the prism. The second laser unit is arranged relative to the polarization coupling prism to cause the second laser beam to impinge on and be reflected at the light exit surface in the same direction as the first laser beam exiting the prism, resulting in a collinear superposition of the first and second laser beams.

An illumination apparatus includes an illumination optical system configured to illuminate a light modulation element; a plurality of light source units each including a fluorescent member, at least one light source, and a light-guiding optical system; and an optical-path combining system. A predetermined region in an area where light source images are formed by the illumination optical system using light beams from the optical-path combining system is defined as an effective region, and the number of the light source units is denoted by N. In this case, the light source images and N subregions obtained by dividing the effective region by N along a first side direction of the effective region or a second side direction orthogonal to the first side direction satisfy a predetermined relation.