A vehicular display device includes a display that emits, as display light, a display image projected onto a windshield, a transparent cover that blocks an opening of a housing and transmits at least a part of the display light emitted from the display, a plurality of reflecting mirrors, and a quarter wave plate. Using a vibration direction of the display light from the display as a reference vibration direction, the quarter wave plate converts the display light transmitted from the transparent cover toward the reflecting mirror into circularly polarized light vibrating in a direction tilted by 45 degree from the reference vibration direction and converts the circularly polarized light transmitted toward the reflecting mirror from the reflecting mirror into display light vibrating in a direction orthogonal to the reference vibration direction.

A catheter system for optical coherence tomography includes an elongate catheter body, an optical fiber in the elongate catheter body, and an anamorphic lens assembly coupled with a distal end of the optical fiber. The optical fiber and the lens assembly are together configured to provide a common path for optical radiation reflected from a target and from a reference interface between the distal end of the optical fiber and the lens assembly.

A vehicular display device includes a display that emits, as display light, a display image projected onto a windshield, a transparent cover that blocks an opening of a housing and transmits at least a part of the display light emitted from the display, a plurality of reflecting mirrors, and a quarter wave plate. Using a vibration direction of the display light from the display as a reference vibration direction, the quarter wave plate converts the display light transmitted from the transparent cover toward the reflecting mirror into circularly polarized light vibrating in a direction tilted by 45 degree from the reference vibration direction and converts the circularly polarized light transmitted toward the reflecting mirror from the reflecting mirror into display light vibrating in a direction orthogonal to the reference vibration direction.

A projection device includes a display that emits a first linearly polarized light that oscillates in a reference oscillation direction, a transparent cover that blocks an opening of a housing, and that reflects the first linearly polarized light that is emitted by the display, and a half-wavelength plate that converts the first linearly polarized light entering from the transparent cover into a second linearly polarized light that oscillates in a direction orthogonal to the reference oscillation direction, and transmits the second linearly polarized light. The transparent cover includes a convex curved surface protruding toward an interior of the housing, and is structured to reflect the first linearly polarized light that is emitted by the display, toward the half-wavelength plate, and to transmit the second linearly polarized light from a reflection mirror toward a combiner.

A catheter system for optical coherence tomography includes an elongate catheter body, an optical fiber in the elongate catheter body, and an anamorphic lens assembly coupled with a distal end of the optical fiber. The optical fiber and the lens assembly are together configured to provide a common path for optical radiation reflected from a target and from a reference interface between the distal end of the optical fiber and the lens assembly.

An optical system includes a light source operable to produce input light, a linear diffuser, and a reflector. The light source, linear diffuser, and reflector are arranged and configured to direct the input light from the light source to the linear diffuser, project diffused light from the linear diffuser to the reflector, reflect the diffused light from the reflector to the linear diffuser as reflected light, and modify the reflected light at the linear diffuser to output a planar fan of diffused light, so that an illumination line forms at an intersection of the planar fan and an object. A system includes an optical sub-system configured to generate a planar fan of diffused light by passing input light through a single linear diffuser twice, and a control sub-system configured to operate the optical sub-system to control use of the planar fan of diffused light.

A catheter system for optical coherence tomography includes an elongate catheter body, an optical fiber in the elongate catheter body, and an anamorphic lens assembly coupled with a distal end of the optical fiber. The optical fiber and the lens assembly are together configured to provide a common path for optical radiation reflected from a target and from a reference interface between the distal end of the optical fiber and the lens assembly.

An optical system includes a light source operable to produce input light, a linear diffuser, and a reflector. The light source, linear diffuser, and reflector are arranged and configured to direct the input light from the light source to the linear diffuser, project diffused light from the linear diffuser to the reflector, reflect the diffused light from the reflector to the linear diffuser as reflected light, and modify the reflected light at the linear diffuser to output a planar fan of diffused light, so that an illumination line forms at an intersection of the planar fan and an object. A system includes an optical sub-system configured to generate a planar fan of diffused light by passing input light through a single linear diffuser twice, and a control sub-system configured to operate the optical sub-system to control use of the planar fan of diffused light.