A projector generates white light from a laser light source and uses the white light for image display. The white light generator has a rectangular light generating lens that generates excitation light of a rectangular shape from the blue light of a blue laser and a phosphor wheel, coated with a phosphor that is irradiated with the excitation light, to emit yellow light. In the phosphor wheel, a length in the vertical direction of a rectangular shape of an irradiation region is represented by v, and a length in the horizontal direction is represented by h, wherein h<v; and a center of the rectangular shape is within any one of a region having an angle of 45° or more and 135° or less and a region having an angle of 225° or more and 315° or less in the phosphor coat region of the phosphor wheel.

An optical combiner includes a curved reflective element and a rotating mirror configured to rotate through a range of angular displacement. During a first time period, the curved reflective element is configured to reflect a first light beam emitted from a first light source to the rotating mirror when the rotating mirror is disposed at a first angular displacement, and the rotating mirror is configured to receive the first reflected light beam and provide a first output light beam along an output optical axis. During a second time period, the curved reflective element is configured to reflect a second light beam emitted from a second light source to the rotating mirror when the rotating mirror is disposed at a second angular displacement, and the rotating mirror is configured to receive the second reflected light beam and provide a second output light beam along the output optical axis.

An observation apparatus includes a display apparatus that displays a display pattern, a display projection optical system that projects a light beam from the display apparatus, and forms an image of the display pattern, a combining optical element that combines a light beam from a sample and a light beam from the display apparatus, and an eyepiece optical system that enables an observer to simultaneously observe an image of the sample and an image of the display pattern, in which a numerical aperture (NA) of a light beam from the display apparatus is smaller than a maximum value of an NA of a light beam from the sample, and is larger than a minimum value of an NA of a light beam from the sample, at a position of an image on an optical path that is formed after light beams are combined by the combining optical element.

There is provided an optical system, including a light-transmitting substrate (20) having at least two external major surfaces and edges, an optical element for coupling light waves into the substrate (20) by internal reflection, at least one partially reflecting surface located in the substrate (20), for coupling light waves out of the substrate (20), at least one transparent air gap film (110) including a base (112) and a hyperfine structure (111) defining a relief formation, constructed on the base, wherein the air gap film is attached to one of the major surfaces of the substrate (20), with the relief formation facing the substrate (20) defining an interface plane (58), so that the light waves coupled inside the substrate (20) are substantially totally reflected from the interface plane (58).

A method for scanning solid angles is provided using at least two electromagnetic beams, at least one electromagnetic beam being generated that is subsequently deflected along a horizontal angle and/or along a vertical angle with the aid of a rotatable mirror; the solid angles being scanned using the at least one electromagnetic beam; and at least one reflected electromagnetic beam being received, after being reflected off an object, by a receiving optics that is pivotable along the horizontal angle synchronously with the mirror. Furthermore, a LIDAR device for carrying out the method is provided.

Shaped optical films and methods of shaping optical films are described. The method includes securing at least portions of a perimeter of the optical film in a first plane so that the secured portions do not move relative to one another; and stretching the optical film by displacing a portion of the optical film along at least a first direction perpendicular to the first plane such that one of a radial and circumferential stretching of the optical film is substantially constant from a center to the perimeter of the optical film, and the other one of the radial and circumferential stretching of the optical film substantially changes from the center to the perimeter of the optical film. The optical film is a reflective polarizer including a plurality of alternating polymeric layers.

Shaped optical films and methods of shaping optical films are described. The method includes securing at least portions of a perimeter of the optical film in a first plane so that the secured portions do not move relative to one another; and stretching the optical film by displacing a portion of the optical film along at least a first direction perpendicular to the first plane such that one of a radial and circumferential stretching of the optical film is substantially constant from a center to the perimeter of the optical film, and the other one of the radial and circumferential stretching of the optical film substantially changes from the center to the perimeter of the optical film. The optical film is a reflective polarizer including a plurality of alternating polymeric layers.

A method includes configuring a first plurality of beamsplitters in a network of interconnected beamsplitters of an optical circuit into a transmissive state. The optical circuit is configured to perform a linear transformation of N input optical modes, where N is a positive integer. The first plurality of beamsplitters is located along a beam path within the optical circuit and traversing a target location. The method also includes configuring a second plurality of beamsplitters in the network of interconnected beamsplitters of the optical circuit into a reflective state to reconfigure the optical circuit into a reconfigured optical circuit. The reconfigured optical circuit is configured to perform a linear transformation on M input optical modes, where M is a positive integer less than N. The second plurality of beamsplitters is located along at least one edge of the optical circuit.

A method includes configuring a first plurality of beamsplitters in a network of interconnected beamsplitters of an optical circuit into a transmissive state. The optical circuit is configured to perform a linear transformation of N input optical modes, where N is a positive integer. The first plurality of beamsplitters is located along a beam path within the optical circuit and traversing a target location. The method also includes configuring a second plurality of beamsplitters in the network of interconnected beamsplitters of the optical circuit into a reflective state to reconfigure the optical circuit into a reconfigured optical circuit. The reconfigured optical circuit is configured to perform a linear transformation on M input optical modes, where M is a positive integer less than N. The second plurality of beamsplitters is located along at least one edge of the optical circuit.

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.