The present invention relates to a reflective eyepiece optical system and a head-mounted near-to-eye display device. The system includes: a first optical element and a second optical element arranged successively in an incident direction of an optical axis of human eyes, and a first lens group located on an optical axis of a miniature image displayer. The first optical element is used for transmitting and reflecting an image light from the miniature image displayer. The second optical element includes an optical reflection surface. The first optical element reflects the image light refracted by the first lens group to the second optical element, and then transmits the image light reflected by the second optical element to the human eyes.

The present invention relates to a reflective eyepiece optical system and a head-mounted near-to-eye display apparatus. The system includes: a first lens group, and a first optical element and a second lens group for transmitting and reflecting a light from a miniature image displayer. The second lens group includes an optical reflection surface, and the optical reflection surface is an optical surface farthest from a human eye viewing side in the second lens group. The optical reflection surface is concave to a human eye viewing direction. The first optical element reflects the light refracted by the first lens group to the second lens group, and then transmits the light refracted, reflected, and refracted by the second lens group to the human eye.

There is provided a projection optical system capable of projecting an image formed on an image forming unit on a projection plane, which has an extremely short projection distance and a small size.

A projection system can include a first modulator including a plurality of pixels in a first modulator surface, a second modulator including a plurality of pixels in a second modulator surface, and an intermediate imaging optical unit, which images the first modulator surface onto the second modulator surface, wherein the intermediate imaging optical unit includes a first lens having a convex side and wherein the convex side of the first lens is a free-form surface, which is not spherical and not rotationally symmetric and does not exhibit any mirror symmetry.

An imaging system, including a light valve and a projection lens, is provided. The projection lens has a reduction side and a magnification side, and includes a lens group and a convex mirror. The light valve is configured on the reduction side. The projection lens is configured to image the beam from the light valve on a projection surface, and the projection surface is configured on the magnification side. There is an included angle between the projection surface and a light receiving surface. The lens group is configured on an optical path between the magnification side and the reduction side, and includes first to seventh lens elements sequentially arranged from the magnification side to the reduction side. The refractive powers of the first to seventh lens elements are respectively negative, negative, positive, positive, negative, positive, and positive. The convex mirror is configured on an optical path between the lens group and the magnification side. A projection device, including the imaging system, is also provided.

A projection optical system (10) projects from a first image plane (5) on a reducing side to a second image plane (6) on an enlargement side. The projection optical system (10) includes a first optical system (11) that includes a plurality of lenses and forms a first intermediate image (51) formed inside the first optical system (11) by light incident from the reducing side into a second intermediate image (52) on the enlargement side of the first optical system (11); a second optical system (12) that includes a first reflective surface (M1) with positive refractive power which is positioned further to the enlargement side than the second intermediate image (52); and a glass block (30) that is disposed between the first optical system (11) and the first reflective surface (M1), the glass block (30) passing light rays from the first optical system (11) to the second intermediate image (52).

The 1-2nd lens group is divided into three lens groups which move when focusing is performed during the magnification change. Even in a case in which the second optical group is formed of one mirror, it is possible for a primary image to contain appropriate aberration and to hereby reduce aberration of an image which is finally projected onto a screen through the second optical group.

A wide-angle projection system includes a refraction unit and a reflection unit. The refraction unit includes a first lens group of positive refractive power and a second lens group of negative refractive power. The second lens group is disposed between the first lens group and the reflection unit and the condition: 0.9<A/B<1.4 is satisfied, where A denotes a distance along an optical axis of the wide-angle projection system and between the refraction unit and the reflection unit, and B denotes a total length of the refraction unit along the optical axis.

A projection optical system of the present disclosure projects onto a projection surface (screen) an image ray bundle formed on an image display element, and includes a transmissive optical system that is positioned on a side of an emission surface of the image display element and has positive power, and a reflective optical system including at least one mirror for reflecting, toward the projection surface, light rays emitted from the transmissive optical system. The transmissive optical system includes an aperture stop, at least one positive lens disposed closer to the image display element than the aperture stop is, a first positive meniscus-shaped lens, a negative lens, and a second positive meniscus-shaped lens with the first and second positive lenses and the negative lens being closer to the projection surface than the aperture stop is. The first and second positive lenses are disposed with the negative lens being disposed therebetween so that their respective concave surfaces face each other. During focusing, a spacing between the first positive lens and the negative lens and a spacing between the second positive lens and the negative lens remain unchanged.

A front projection display device is provided including an image-generating source configured to generate an image, a wide angle lens system adapted to receive the image, and a screen. The wide angle lens system may be configured to increase distortion of the image in a first stage and decrease distortion of the image in a second stage. The screen may be configured to receive the image from the wide angle lens system on a first side and reflect the image back to a viewer on the first side. In another embodiment, a screen is provided for a front projection system, the screen may be configured to receive light from a steep angle and may include any number of surface topographies configured to reflect light back to the viewer along a desired viewing plane.