A head-up display includes a display device that displays an image toward a vertically downward direction, a first mirror that reflects the image to output reflected light toward a vertically upward direction, and a second mirror that reflects the reflected light from the first mirror to output reflected light toward a vertically upward direction. A vehicle includes the head-up display, and a windshield that reflects the reflected light emitted from the head-up display.

A cloaking device includes object-side and image-side curved cloaking region boundaries with outward facing mirror surfaces and inward facing opaque surfaces. A cloaking region is bounded by the inward facing opaque surfaces of the object-side and image-side curved CR boundaries. An object-side curved reflection boundary with an inward facing mirror surface is positioned proximate to the object-side curved cloaking region boundary and an image-side curved reflection boundary with an inward facing mirror surface is positioned proximate to the image-side curved cloaking region boundary. Light from an object located on the object-side of the cloaking device and obscured by the cloaking region is redirected around the cloaking region by the outward facing mirror surfaces of the object-side and image-side curved cloaking region boundaries and the inward facing mirror surfaces of the object-side and image-side curved reflection boundaries.

Provided is a head-up display capable of displaying a plurality of virtual images presented at different distances while increasing the design flexibility in the display device for creating the virtual images. The head-up display comprises: a first display surface disposed to extend the light path of first image light emitted toward a viewer and a second display surface disposed to make the light path of second image light emitted shorter than that of the first image light; a first concave reflector for reflecting the first image light and the second image light; and a second concave reflector for reflecting the image light reflected from the first concave reflector. The first concave reflector is configured such that the first image light and the second image light intersect with each other in the vertical direction between the first concave reflector and the second concave reflector.

A light irradiation apparatus that splits white light into light rays of a plurality of wavelengths to apply the light ray includes a white light source, a diffraction grating that splits white light emitted by the white light source into light rays of a plurality of wavelengths, and a light selector that selects a light ray of a specified wavelength from the light rays of the plurality of wavelengths split by the diffraction grating.

A head-up display device includes optical path deflecting means, a first mirror having power, a second mirror having power, and a light-blocking member that is provided with an aperture. Display light emitted from an image display surface is reflected by the optical path deflecting means, the first mirror, and the second mirror in this order, passes through the aperture, and reaches an image reflective surface. The image display surface and the optical path deflecting means are disposed on the same side as an observer and on a side opposite to the first mirror with respect to luminous flux that travels toward the aperture from the second mirror, and the image display surface is disposed on a side opposite to the second mirror with respect to luminous flux that travels toward the first mirror from the optical path deflecting means.

An off-axis hybrid surface three-mirror optical system comprises a primary mirror, a secondary mirror, a tertiary mirror, and an image sensor. A reflective surface of the primary mirror is a sixth-order polynomial freeform surface of xy. A reflective surface of the secondary mirror is a sixth-order polynomial aspheric surface of xy. A reflective surface of the a tertiary mirror is a spherical surface of xy.

A method of applying a reflective optics system that requires the presence of both convex and a concave mirrors that have beam reflecting surfaces. Application thereof achieves focusing of a beam of electromagnetic radiation with minimized effects on a polarization state of an input beam state of polarization that results from adjustment of angles of incidence and reflections from the various mirrors involved.

A cloaking device includes object-side and image-side curved cloaking region boundaries with outward facing mirror surfaces and inward facing opaque surfaces. A cloaking region is bounded by the inward facing opaque surfaces of the object-side and image-side curved CR boundaries. An object-side curved reflection boundary with an inward facing mirror surface is positioned proximate to the object-side curved cloaking region boundary and an image-side curved reflection boundary with an inward facing mirror surface is positioned proximate to the image-side curved cloaking region boundary. Light from an object located on the object-side of the cloaking device and obscured by the cloaking region is redirected around the cloaking region by the outward facing mirror surfaces of the object-side and image-side curved cloaking region boundaries and the inward facing mirror surfaces of the object-side and image-side curved reflection boundaries.

A multifocal rain sensor includes: at least one light emitting unit configured to output light; a first reflective plate corresponding to the at least one light emitting unit and disposed at a position spaced apart from the at least one light emitting unit by a predetermined distance; a glass part reflecting light after the light is reflected by the first reflective plate and forming a sensing region; a second reflective plate re-reflecting the light reflected by the glass part; and a light receiving unit configured to receive the light reflected by the second reflective plate. The second reflective plate includes a multifocal reflective plate having a plurality of focuses based on a vertical height of incident light that varies according to a change in thickness of the glass part.

Provided is a head-up display capable of displaying a plurality of virtual images presented at different distances while increasing the design flexibility in the display device for creating the virtual images. The head-up display comprises: a first display surface disposed to extend the light path of first image light emitted toward a viewer and a second display surface disposed to make the light path of second image light emitted shorter than that of the first image light; a first concave reflector for reflecting the first image light and the second image light; and a second concave reflector for reflecting the image light reflected from the first concave reflector. The first concave reflector is configured such that the first image light and the second image light intersect with each other in the vertical direction between the first concave reflector and the second concave reflector.