Abstract: The invention provides a method and a system for generating a polarized propagation-invariant light field. The system includes a laser source, a spatial light modulator, a computer, a first lens, a shading element, a first quarter-wave plate, a second quarter-wave plate, a second lens, and a beam combining element. In the present invention, two Laguerre-Gaussian mode beams that satisfy a particular Gouy order relationship are generated, and orthogonal even polarization is applied to the two Laguerre-Gaussian mode beams. The two Laguerre-Gaussian mode beams are then focused onto a Ronchi grating to be stably combined into polarized propagation-invariant light field. The light field generated in the present invention simultaneously has linear polarization, elliptical polarization, and circular polarization in a cross section of the light field, and in a propagation process of the light field in free space, apart from normal spot size scaling, polarization distribution remains unchanged.

Abstract: A manufacturing method creates a type of telescope which is athermal, lightweight, optical quality for visible and IR applications. The method includes: a) optical mirrors being made by immersing a master, that is an optical component with a curvature opposite to the mirror required into an electrolytic bath where the applied current transfers metal ions and deposit them on the master, the cathode, as a layer, b) the layer being bonded by an adhesive, solder or any other attachment process to a mechanical reinforcing structure, c) after the hardening of the bond or glue, the thin layer being finally released from the master and having maintained the optical quality of the master. The master or mandrel can be cleaned and reused for repeating this method and manufacturing large series of telescopes.

Abstract: The information display apparatus configured to display video information of a virtual image on a reflecting surface of conveyance includes: a display configured to display the video information; and a virtual image optical system configured to display a virtual image at a front of the conveyance by reflecting light emitted from the display by means of the reflecting surface. The virtual image optical system includes a concave mirror and an optical element. The optical element is arranged between the display and the concave mirror, and is configured to correct distortion of the virtual image obtained so as to correspond to a viewpoint position of a driver on a basis of a shape of the concave mirror and a shape of the optical element. The information display apparatus further includes a virtual image double image conversion reducer configured to reduce double image conversion of the virtual image.

Abstract: An imaging optical system according to the present disclosure includes: an aperture stop; an image-forming optical system that causes an image to be formed toward an imaging plane of an image sensor; and an optical phase modulator that includes a substance having a birefringence index, and gives two pupil functions to the image-forming optical system. The following conditional expressions are satisfied: 1?(2×L×tan(w)+D)/D<1.4??(1) ?/4*0.75<Re<?/4*1.1??(2), where L: a distance between the aperture stop and the optical phase modulator; D: an aperture diameter (diameter) of the aperture stop; w: a maximum angle of incidence of a principal light ray that enters the aperture stop; ?: a wavelength of light; and Re: phase retardation caused by birefringence of the optical phase modulator.

Abstract: A method for increasing speckle spot density, comprising: acquiring light splitting dot array, which is used for performing array copying on multi-point light source and projection to form speckle spot array; acquiring minimum neighboring point spacing or average value of neighboring point spacing of all or part of light-emitting points in the multi-point light source; dividing light splitting dot array into first light splitting dot array and second light splitting dot array, speckle spot array formed by projection by first light splitting dot array being located in first speckle spot area, and speckle spot array formed by projection by second light splitting dot array being located in second speckle spot area; and performing expansive copying on each light splitting dot in second light splitting dot array so as to form third light splitting dot array.

Abstract: There is provided an imaging lens having a low profile and a low F-number and allowing satisfactory correction of aberrations. An imaging lens comprises in order from an object side, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3, a fourth lens L4 with positive refractive power, and a fifth lens L5 with negative refractive power, wherein an image-side surface of said fourth lens L4 is convex in a paraxial region, an object-side surface of said fifth lens L5 is an aspheric surface having at least one inflection point, and the following conditional expressions are satisfied: f/Dep<2.0??(1) 1.2<T3/T2<1.8??(2) 15<vd3<35??(3) ?1.0<R5f/R5r<?0.

Abstract: The optical system includes a projector, a deflector, a polarizer, a first grating coupler structure, and a second grating coupler structure. The projector emits three beams having different wavelengths. The deflector is disposed below the projector and is configured to change incident angles of the three beams and to focus the three beams at the same region of the first grating coupler structure. The first grating coupler structure is below the deflector and is configured to couple the three beams into a light-guide lens such that the three beams travel the same optical path within the light-guide lens. The light-guide lens is connected to the first grating coupler structure and is configured to transmit the three beams. The polarizer is disposed between the projector and the deflector and is configured to filter out transverse electric (TE) modes or transverse magnetic (TM) modes of the three beams.

Abstract: Systems of the present disclosure can provide a head-mountable device with a head securement element that allows a user to adjust how the head securement element fits near the ears of the user. Examples of adjustment mechanisms described herein allow a user to control the size, shape, flexibility, and/or position of certain regions of the head securement element with respect to the ears of the user. Accordingly, the user can select a configuration that distributes forces evenly, maximizes comfort, and allows the user to enjoy the head-mountable device for longer durations of time.

Abstract: A system for imaging a retina of an eye includes a first lens for positioning proximate to the eye; a light source positioned to illuminate the eye when the system is aligned with the eye; an image sensor adapted to capture a retinal image of the retina through the first lens; an aperture disposed along an optical path extending from the image sensor and passing through the first lens; and a processing apparatus communicatively coupled to the image sensor and the light source, wherein the processing apparatus includes logic that when executed by the processing apparatus causes the system to perform operations including: illuminating the eye with the light source and capturing the retinal image with the image sensor.

Abstract: A method for producing a camera module. An objective is aligned with respect to an image sensor and is then fixed in position by being joined to a support that receives the image sensor, a housing that surrounds the image sensor, or an interposed connection structure as a joining partner. The objective is mounted on spacer elements, which are initially still movable, and is then aligned with respect to the image sensor by moving the spacer elements. After the objective is aligned, the spacer elements are welded to the objective and the joining partner. A camera module is also described.

Abstract: A projection system includes a first optical system and a second optical system disposed on an enlargement side of the first optical system. The first optical system includes a first lens group having positive power, a second lens group disposed on the enlargement side of the first lens group and having negative power, and an optical path deflector disposed between the first lens group and the second lens group. The second optical system includes a reflection member having a concave reflection surface. The second lens group includes three aspherical lenses. Conditional Expression (1) below is satisfied, 0.25<|F|×FNO/Ymax<0.5??(1) where F represents the focal length of the entirety of the projection system, FNO represents the F number of the projection system, and Ymax represents a maximum image height in a reduction-side conjugate plane.

Abstract: 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.

Abstract: In various embodiments, alignment systems for laser resonators generate near-field and/or far-field images of input beams produced by the laser resonators to enable the alignment of the input beams.

Abstract: An image relay system is presented that includes an opposing pair of rod lens assemblies positioned symmetrically with respect to a central airspace. The rod lens assemblies include a meniscus lens positioned immediately adjacent to a central airspace and with the convex surface facing the airspace, a first lens having positive optical power with a convex face positioned adjacent to the inner face of the meniscus lens, a rod lens adjacent to the first lens having positive power, and a second lens having positive optical power positioned adjacent to the rod lens, the relay system designed so that light across a broad spectrum come to a common focus, as well as correcting for spherical aberration across the broad spectrum. An endoscope employing this relay system is also presented.

Abstract: A photographing lens system includes eight lens elements which are, in order from an object side to an image side along an optical path: a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element, a seventh lens element and an eighth lens element. Each of the eight lens elements has an object-side surface facing toward the object side and an image-side surface facing toward the image side. The first lens element has positive refractive power. The second lens element has negative refractive power. The seventh lens element has negative refractive power. The image-side surface of the eighth lens element is concave in a paraxial region thereof, and the image-side surface of the eighth lens element has at least one inflection point.

Abstract: An optical calibration tool includes a first body, a light emitter, a light receiver, a second body, and a light reflecting member. The first body has a first engaging port and a second engaging port. The light emitter and the light receiver are disposed in the first body. The second body has a third engaging port and a channel communicated with each other. The third engaging port is configured to selectively engage one of the first engaging port and the second engaging port. When the third engaging port is engaged with the first engaging port, the light emitter is optically coupled to the light reflecting member. When the third engaging port is engaged with the second engaging port, the light receiver is optically coupled to the light reflecting member.

Abstract: An optical assembly having at least a first optical element and a second optical element, both of which are arranged to be movable in a guided manner, is provided. A guide common to both optical elements is present, which provides a guide path that is common to both optical elements during the guided movement of the first optical element and during the guided movement of the second optical element.

Abstract: A head-mounted fixing device includes: a head frame including two side frame portions, and a front frame portion located between the two side frame portions and connected to the two side frame portions, and the two side frame portions and the front frame portion being made of rigid materials; an elastic piece including one end connected to the front frame portion; a headgear including an arc portion and a top portion, wherein two ends of the arc portion are respectively connected to the two side frame portions, one end of the top portion is connected to another end of the elastic piece, and another end of the top portion is connected to the arc portion; it is characterized in that the front frame portion is used to abut against a user's forehead to provide a fulcrum.

Abstract: An exemplary illumination source is provided. The illumination source includes a light integrating device for coupling to at least one optical structure at an output port. The light integrating device includes at least one input port. At least one light source produces at least one optical illumination coupled to the at least one input port. A light adjusting tool controls the optical illumination emitted by the light integrating device. The light adjusting tool controls uniformity of light emitted by the light integrating device by modifying at least one internal surface of the light integrating device.

Abstract: Protective lens for a laser module as well as systems that incorporate the lens. In one embodiment, a laser module system is disclosed. The laser module system includes a light-emitting diode lighting apparatus, a laser module that includes a laser-emitting aperture having a first dimension, and a protective lens that is disposed over the light-emitting diode lighting apparatus and the laser module. The protective lens includes both a smaller diameter portion that is configured to protect the laser module and a larger diameter portion that is larger in size than the smaller diameter portion and is configured to protect the light-emitting diode lighting apparatus. The smaller diameter portion is offset by an angle with respect to the larger diameter portion with the angle of offset being configured to eliminate extraneous reflections of light from the laser-emitting aperture of the laser module.