Optical systems including a partial reflector, a reflective polarizer, and a retarder disposed between the partial reflector and the reflective polarizer are described. The reflective polarizer is curved about two orthogonal axes and includes at least one layer that is substantially optically uniaxial at at least one location. The optical system is adapted to provide an adjustable focus.

Described examples include a beam spreader having a first beam splitter arranged to receive light from a light source, the first beam splitter arranged to pass a first portion of the light in a first direction and reflect a second portion of the light; a second beam splitter arranged to receive the second portion of the light and reflect a third portion of the light in a second direction parallel to the first direction and arranged to pass a fourth portion of the light; and a mirror arranged to receive the fourth portion of the light and reflect the fourth portion of the light in a third direction parallel to the first direction, wherein the third portion and the fourth portion of the light reflected from the mirror is separated from the first portion of the light in the spreading direction.

A method of fabricating a light-guide optical element having a plurality of partially reflecting surfaces is disclosed. The method includes providing a plurality of transparent plates, each plate polished on two opposite surfaces such that the surfaces are parallel to each other, coating a first of the surfaces of a subset of plates with a first coating, coating a second of the surfaces of the subset of plates with a second coating; bonding together the plurality of transparent plates to form a stack, and cutting the stack along parallel planes obliquely angled to the faces of the transparent plates so as to form the optical element, wherein the first coating is a partially reflective coating have a first set of mechanical properties, and the second coating is selected from the group consisting of: a coating similar to the first coating and a non-reflective coating having a second set of mechanical properties substantially similar to the first set of mechanical properties.

An optical package includes a beam combiner that combines laser light from a laser unit into a single laser beam, a movable mirror apparatus, and a fixed folding mirror which reflects the single laser beam toward the movable mirror apparatus. Beam equalizer optics cause increase of a slow axis divergence rate of the single laser beam such that its slow axis divergence rate is equal to its fast axis divergence rate. The movable mirror apparatus directs the single laser beam through an exit window. The beam equalizer optics include at least one negative spherical lens shaped such that a slow axis divergence rate of incident light is increased but a fast axis divergence rate of incident light is unaltered.

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 measurement system includes a light source configured to emitting a source light, a detection platform configured to support a reference sample and a test sample; a light guiding element on an optical path of the source light; and a detector. The detection platform is configured to synchronously move the reference sample and the test sample on a same surface of the detection platform. The light guiding element is configured to divide the source light into a measurement light and a reference light and guide the measurement light to the test sample, and the reference light to the reference sample. The measurement light reflected by the test sample and the reference light reflected by the reference sample are combined as an interference light. The detector is configured to receive the interference light and obtain optical information of the test sample according to the interference light.

Laser light emanates from optical components that are mounted on a substrate, each optical component being coupled to an optical fiber that delivers laser radiation combined from multiple lasers. A linear or elliptical holographic diffuser is located to diffuse the light emanating from the optical components. The laser wavelengths excite plant photopigments for predetermined physiological responses, and the light source intensities may be temporally modulated to maximize photosynthesis and control photomorphogenesis responses. Each laser is independently controlled. At least one laser emits ultraviolet-C radiation.

A head-up display for a vehicle, the head-up display including a picture generating unit arranged to generate a picture on a light receiving surface; and an optical system arranged to image the picture, where the optical system includes an input arranged to receive light of the picture; an output arranged to output light forming an image of the picture; a first mirror and second mirror arranged to guide light from the input to the output along an optical path, where the optical path includes a first optical path from the input to the second mirror including a transmission through the first mirror; and second optical path from the second mirror to the output including a reflection off the first mirror.

An image display device of the present disclosure includes: a first optical unit configured to change a traveling direction of an optical path by refracting light from a display element; a second optical unit to which the light refracted by the first optical unit enters; and a control unit configured to set a timing to change the traveling direction of the optical path to a state that is different among a plurality of regions, which are determined by dividing a display region of the display element in a scanning direction by controlling a distance between the first optical unit and the second optical unit so as to correspond to each of the plurality of regions.

The invention discloses an X-type adjustment module, comprising a cover, a first frame, a second frame, a first light transmitting element, a second light transmitting element, a first adjustment member, and a second adjustment member. The first frame is pivotally connected to the cover. The second frame is pivotally connected to the first frame and intersects the first frame. The first light transmitting element is fixed in the first frame. The second light transmitting element is fixed in the second frame and intersects the first light transmitting element. The first adjustment member passes through the cover and abuts against the first frame. The second adjustment member passes through the cover and abuts against the second frame. A transmission path of a light beam is controlled by adjusting disposition angles of the first light transmitting element and the second light transmitting element to avoid excessive concentration of light energy.