Minolta Company, Ltd.

Minolta Camera Kabushiki Kaisha

Konica Minolta Photo Imaging, Inc.

Konica-minolta Holdings, Inc.

Ichiro Kasai

Yasushi Tanijiri

Hideki Nagata

Takeshi Endo

Hiroaki Ueda

Yasushi Kobayashi

Kohtaro Hayashi

Tetsuya Noda

Hiromu Mukai

Soh Ohzawa

Jun Ishihara

Kenji Ishibashi

Akira Sato

Yoshie Shimizu

Katsuto Tanaka

Takao Kobayashi

Shigeto Ohmori

Takashi Morimoto

Ichiro Tsujimura

Yasumasa Sugihara

Hiroshi Yamaguchi

Variation of the wavelength of the light emitted from a light source is reduced by a wavelength variation reduction mechanism. Hence, wavelength deviation of the intensity peak of the light emitted from the light source from the diffraction-efficiency peak of a hologram optical element is reduced. Thus, even when a high-brightness light source is used, the light emitted therefrom can be diffracted with the hologram optical element efficiently. Moreover, the heat generated by the light source is efficiently rejected through the surface of a land portion of a flexible printed circuit, is then, via an insulating layer of the flexible printed circuit, efficiently absorbed through the surface of a heat absorbing member, and is then, via a shield conductor, led out of a casing, so as to be thereby expelled.

Image display apparatus and head-mounted display

A hologram optical element is formed on a substrate so as to make an optical device. The hologram optical element is formed in an area smaller than an irradiation area of a beam for reproduction such as image light or object light on the substrate. Supposing that the beam for reproduction is made of a center beam having intensity higher than 50% of center intensity and other peripheral beam, the hologram optical element is formed on the substrate in a size for diffracting only the center beam so that a flare or a ghost can be relieved without using additional optical elements such as a shading plate.

Optical holographic device with a hologram optical element on an area smaller than an irradiation area, holographic image display device and head mounted display with a hologram optical element on an area smaller than an irradiation area

A display apparatus which has a mirror with a free curved reflective surface of which curvature fluctuates with inflection points, a liquid crystal display (LCD), a back light and a polarizer. Light of an image which was modulated by the LCD is reflected by the free curved reflective surface and passes through the polarizer. Then, the light is directed to an optical pupil. Since the curvature of the free curved reflective surface fluctuates with inflection points, curvature of field and distortion can be corrected properly, and an image of high quality can be formed.

Optical system and display apparatus

The exposure amounts of R, G, and B laser light emitted from a fabrication light source are so adjusted that the diffraction efficiency at R, G, and B wavelengths in an optical element is commensurate with the light intensity at the R, G, and B wavelengths in the light emitted from a reproduction light source. For example, when the light intensity of the light emitted from the reproduction light source is increasingly low at the B, G, and R wavelengths in this order, the exposure amounts of the R, G, B, laser light emitted from the fabrication light source are so adjusted that the diffraction efficiency in the optical element is increasingly high at the B, G, and R wavelengths in this order. In this way, the hue of the light (reproduction light) obtained from the reproduction light source via the optical element can be adjusted to the hue desired with every reproduction light source used, while the most use is made of the light emitted from the reproduction light source actually used.

Method for producing an optical device, optical device, image display apparatus, and head-mounted display

A display device has a plurality of light emitting elements for emitting lights, a display element for modulating the light emitting from the plurality of light emitting elements so as to convert it to an image light showing an optical image, a reflection type hologram element, having a positive optical power with respect to the lights from the plural light emitting elements, for diffracting and reflecting the lights from the plural light emitting elements to approximately one direction so as to guide the diffracted and reflected lights to the display element; and an enlarging optical system for forming an enlarged image of the optical image converted by the lights from the image display element. The plural light emitting elements are positioned in a plane approximately vertical to an optical path of the lights diffracted and reflected by the hologram element. The hologram element is tilted to a direction facing the plural light emitting elements with respect to the optical path of the lights diffracted and reflected by the hologram element.

Display device

A head-mounted image display apparatus is provided with: an image display element; a projection optical system that projects an image displayed by the image display element, so as to be enlarged; a reflective screen onto which the image is projected by the projection optical system; and a combiner disposed between the projection optical system and the screen. The combiner transmits the image light from the projection optical system and directs it to the screen, and reflects the image light reflected at the screen and directs it to the user's pupil.

Head-mounted image display apparatus

An image display apparatus has an observation room for housing an observer, and the side faces, floor face, and ceiling face of the observation room are used as screens, onto which images displayed on a smaller number of image display devices than the number of screens are projected. At least one image display device displays, on a time-division or screen-division basis, images to be projected onto two or more screens so that images are projected onto all of the screens.

Image display system

An information display device provided with a prism having at least two reflecting surfaces arranged in facing each other and a hologram surface formed of a reflection-type hologram. And at least one of the two reflecting surfaces is a light-beam-selective surface that selectively transmits or reflects light in accordance with its incident angle. An image light emitted from an image display means enters the prism, and is reflected between the reflecting surfaces, and then is diffractively reflected on the hologram surface, and, after being transmitted through the light-beam-selective surface, is directed to an observer's pupil.

Information display device

A viewing optical system of an optical apparatus has an objective system for forming an image of an object and an eyepiece system for enlarging and directing the image to the pupil. The viewing optical system also has a hologram combiner comprising holograms of the volume type, phase type, and reflective type and having optical power for constructing a surface which is optically equivalent to the image surface at a different position than the image when viewed from the pupil. The system also includes an information display means for displaying information at the position of the equivalent surface, wherein the hologram combiner transmits light from the image and reflects light from the information display means so as to allow viewing of an image together with the information display overlaid onto the image.

Optical apparatus and viewing optical system thereof which is capable of displaying information

A simple, compact optical system is provided that includes a transmissive optical element and a HOE but that nevertheless does not require an extra optical element for the correction of chromatic aberration. The HOE is designed to have diffractive efficiency for each of R, G, and B light beams and have different focal lengths for those light beams so as to correct the longitudinal chromatic aberration produced by a rectangular parallelepiped prism. This eliminates the need for an extra means for correcting the chromatic aberration produced by the prism. The HOE may be designed to exhibit different angles of diffraction for the R, G, and B light beams so as to correct the chromatic aberration produced perpendicularly to the optical axis by a wedge-shaped prism.

Optical system and method for fabricating a holographic optical element

An image display apparatus is provided for providing a virtual image to an observer. The image display apparatus includes an image display unit, an eyepiece optical system, and a container. The image display unit is for providing modulated light corresponding to the virtual image. The eyepiece optical system is for directing the modulated light from the image display unit to one or both of the observer's eyes. The container is for supporting the image display unit on an edge portion of the eyepiece optical assembly.

Image display apparatus

A holographic element is a reflective holographic element formed on a substrate and constituted by a composite hologram having a plurality of patterns of interference fringes composed of interference fringes nonparallel to the substrate. The holographic element forms, out of image light having a predetermined wavelength width emanating from an image display element, a plurality of observation pupils at spatially different locations, and acts in such a way as to fulfill prescribed conditions for an identical incident ray over the entire area in which the image light is incident on the holographic element.

An image display apparatus has a signal input portion for receiving an image signal, an image compensator for electrically compensating the image signal for distortion so that a left and a right image displayed in an observer's left and right eyes have identical distortion and then outputting a left and right image signal that correspond to the left and right images, a signal switcher for switching between the left and right image signals output from the image compensator so as to output the left and right images alternately chronologically, a single two-dimensional image display device for displaying a two-dimensional image in accordance with the image signal output from the signal switcher, a pair of left and right eyepiece optical systems for directing image light exiting from the two-dimensional image display device to the observer's left and right eyes so that the two-dimensional image is displayed as a virtual image in the observer's eyes, and an optical path switcher for time-divisionally switching optical paths from the two-dimensional image display device to the observer's eyes in synchronism with switching between the left and right image signal output from the signal switcher so that the image light enters either the observer's left or right eye at a time.

A compact, high resolution projection imaged display device using a reflective-type display element which uniformly illuminates the entirety of the display element without reducing illumination efficiency and ensures viewing conditions of excellent and uniform brightness extending to the fringe of the field of view is provided by an illumination optical system for redirecting illumination light from an illumination light source onto a reflective-type display element. The reflective-type display element reflects light into the viewing optical system wherein the illumination optical system is constructed so as to have an approximate conjugate relationship between the pupil of the user and the illumination light from the illumination light source.

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Toyonaka, Japan

Ichiro Kasai