Konica Minolta Opto, Inc.

Konica Minolta, Inc.

Minolta Company, Ltd.

Masayuki Imaoka

Jun Ishihara

Kohtaro Hayashi

Yasumasa Sawai

Keiko Yamada

Tomokazu Masubuchi

Soh Ohzawa

Masahiro Terada

Sadanobu Imamura

Yuichi Atarashi

Hiroshi Kibayashi

Atsushi Matsuura

Tomiei Kuwa

A projection display apparatus includes a reflective image display element having an image display surface including micromirrors, a prism unit bending an optical path of illumination light and transmitting image light, and a projection optical system. The prism unit has an air gap tilted with respect to a principal ray of the image light emitted from the center of the image display surface, and the image light passes through the air gap. The projection optical system includes an aperture stop with a noncircular aperture so shaped that part of a circular aperture in a peripheral portion thereof is cut off in a shape of a segment to serve as a shade portion, and image light corresponding to an end portion at a side where an incidence angle with respect to the air gap is large in an F-number beam is blocked by the shade portion satisfying predetermined conditions.

Projection display apparatus

An optical unit that directs illumination light to a plurality of digital micromirror devices that produce projection light by modulating the illumination light on an image display surface according to an image signal, and that transmits and emits the projection light, the optical unit includes: a plurality of first prisms, wherein the projection light exits a first face of a most emergence-side first prism among the first prisms; and a second prism disposed next to the first prisms, wherein the second prism includes: a 2A-th face into which the projection light enters; and a 2B-th face disposed perpendicular to an optical axis of the projection light, the projection light exits the 2B-th face, the second prism is wedge-shaped with the 2A-th and 2B-th faces not being in parallel with each other.

Optical unit and projector therewith

A projection-type display device, provided with: a reflection-type image display element (DP), in which illumination light is reflected at an image display surface so as to be converted to image light and emitted; a prism unit (PU) that bends a light path of the illumination light and transmits image light; and a projection lens system (PO) that projects the image light transmitted through the prism unit onto a screen. The prism unit (PU) has an air gap (AG) that is disposed obliquely with respect to the main light rays of the image light emitted from the center of the image display surface. At least one lens (DL) in the projection lens system (PO) is eccentric in relation to the optical axis of the projection lens system (PO) so that comatic aberration produced when the image light is transmitted through the air gap (AG) will be canceled out.

Projection-type display device

An illumination optical system includes a lens group, a diaphragm, and a prism unit including first to third prisms and a rotationally-asymmetrical curved reflective surface having a positive power and satisfying the conditional formula: PYa/PZa&#x3c;PYb/PZb, where Pya, Pyb represent powers of the curved reflective surface at positions of points a, b, respectively within a reference plane formed in the prism unit by rays passing through centers of the lens group and the diaphragm, and PZa, PZb represent powers of the curved reflective surface at positions of points a, b, respectively, within a plane including normal lines of the reference plane and the curved reflective surface, points a and b representing where the principal ray of a beam illuminating the area nearest and farthest, respectively, to the lens group impinges on the curved reflective surface, along an intersection line between an image display surface and the reference plane.

Illumination optical system and projector

In an optical unit, illumination light is directed to a plurality of digital micromirror devices that produce projection light by modulating the illumination light on an image display surface according to an image signal. The optical unit emits the projection light produced by the digital micromirror devices. The optical unit includes: a reflector having an illumination light reflecting face on which the illumination light is reflected; and a prism unit composed of a plurality of first prisms. The reflected illumination light enters the prism unit via a first face of a most emergence-side first prism among the first prisms and the projection light exits via the first face.

A projection display apparatus includes: a micromirror device that reflects light on an image display surface to emit image light; a prism unit that bends an optical path of the image light emitted from the micromirror device; and a projection optical system that includes a diaphragm and that projects the image light emitted from the prism unit onto a screen, wherein the image display surface is formed with a plurality of micromirrors, and an image is formed on the image display surface through ON/OFF control on a tilt of a surface of each of the micromirrors and intensity modulation on incident light, the prism unit has an air gap tilted at a predetermined angle with respect to a principal ray of the image light emitted from the center of the image display surface, and the image light emitted from the micromirror device passes through the air gap.

Projection display apparatus and method of producing said apparatus

A projection optical system () comprises a relay optical system (), a PBS prism (), and two projection lenses (). The image light beam from a DMD () enters the PBS prism () via the relay optical system (), is polarization-split there, and is directed to a screen by means of the two projection lenses (). Displaying an image by means of the DMD () is controlled while the polarized states of the light beams produced by the polarization split by means of the PBS prism () are controlled. Thereby, a three-dimensionally viewable image and a high-resolution image created by pixel-offset can be projected. Since the relay optical system () is provided, the lens backs of the projection lenses () can be shortened, and the projection lenses () and further the projection optical system () can be made compact.

Projection optical system and image projecting device

A projection optical system receives light from a display device surface and enlarges and projects a display image thereon onto a screen surface. The projection optical system includes one or more reflective surfaces having an optical power between the display device surface and the screen surface, moves at least one optical device having an optical power to adjust focus and satisfies the following conditional formula: &#x2212;0.02&#x3c;{(&#x3b4;1&#x2212;&#x3b4;2)&#x3b2;2}/{(&#x3b4;1+&#x3b4;2)&#x3b2;1}&#x3c;0.2 where &#x3b4;1 and &#x3b4;2 represent, when the absolute value of a projection magnification is the highest and the lowest, respectively, during focus adjustment, the absolute value of a difference between a distance from the exit pupil of rays incident on the screen upper ends of the screen surface to the screen surface and a distance from the exit pupil of rays incident on the screen lower ends of the screen surface to the screen surface and &#x3b2;1 and &#x3b2;2 represent the maximum value and minimum value, respectively, of the projection magnification when focus is adjusted.

Projection optical system

Provided is an optical system (PS) which is used in a wavelength range including a near ultraviolet light range having a wavelength longer than approximately 350 nm and a visible light range. The optical system includes at least two first positive lenses which satisfies a predetermined conditional expression concerning anomalous dispersion characteristic and a rate of change of the refractive index with respect to temperature, and is disposed closer to a contraction side than an aperture stop (ST), and at least one second positive lens which satisfies a predetermined conditional expression concerning anomalous dispersion characteristic and a rate of change of the refractive index with respect to temperature.

Optical system, image projection apparatus including the same and an image pickup device

A projection optical system satisfies a conditional formula: 0.01&#x3c;{(tan &#x3b8;f1&#x2212;tan &#x3b8;f2)&#x2212;(tan &#x3b8;n1&#x2212;tan &#x3b8;n2)}&#xb7;(&#x3b2;2/&#x3b2;1)&#x3c;0.20 where the direction of a normal to and the direction of a long side of the screen of the screen surface are referred to as a 'z-direction' and an 'x-direction', respectively, the x-z plane component of the angle of incidence with respect to the screen surface is referred to as an &#x201c;incident angle &#x3b8;&#x201d; and when, among rays that pass through the center of an aperture and that are incident on the ends of the upper and lower sides of the screen of the screen surface, the incident angle &#x3b8; of rays whose incident angle &#x3b8; is larger is referred to as &#x201c;&#x3b8;f&#x201d; and the incident angle &#x3b8; of rays whose incident angle &#x3b8; is smaller is referred to as &#x201c;&#x3b8;n&#x201d;, &#x3b8;n and &#x3b8;f2 respectively represent, when the absolute value of a projection magnification is the highest or lowest during focus adjustment, the incident angle &#x3b8;f, &#x3b8;n1 and &#x3b8;n2 respectively represent, when the absolute value of the projection magnification is the highest or lowest during focus adjustment, the incident angle &#x3b8;n, and &#x3b2;1 and &#x3b2;2 respectively represent the maximum and minimum values of the projection magnification during focus adjustment (except that &#x3b2;1 and &#x3b2;2 respectively represent, if the projection magnification is negative, a value of the projection magnification when the absolute value thereof is the highest or lowest).

An oblique projection optical system enlarges an image formed on a display device surface, and obliquely projects the enlarged image on a screen surface. The oblique projection optical system has, in the order from a reduction side: a refraction optical portion having a positive optical power, a concave reflection surface having a positive optical power, and a convex reflection surface having a negative optical power. The refraction optical portion includes a rotationally symmetric coaxial refraction group. An intermediate image of the image formed on the display device surface is formed between the refraction optical portion and the concave reflection surface. An aperture stop image is formed between the concave reflection surface and the convex reflection surface. The concave reflection surface and the convex reflection surface fulfill prescribed conditional formulae.

Oblique projection optical system

The projection optical system uses a plurality of wavelengths or a wavelength band within a wavelength range from a visible region to a near ultraviolet region. The double-telecentric projection optical system includes: a first lens group with a positive power; a second lens group with a negative power, including a predetermined lens or lenses; and a third lens group with a positive power, including a stop and at least two positive lenses satisfying a predetermined condition relating to refractive index. The projection optical system satisfies a predetermined condition relating to a composite focal length of the first lens group and the second lens group, and a focal length of the third lens group.

A rear projector for performing image projection includes: a screen and a projection optical system. The screen has a rotationally symmetric Fresnel lens. The projection optical system has at least one reflection surface formed of a rotationally asymmetric free curved surface. The projection optical system is nonaxisymmetric and makes a central principle ray incident obliquely on the screen in the image projection. The Fresnel lens has aberration that cancels out pupil aberration of the projection optical system so that principal rays of beams exiting from the Fresnel lens become substantially parallel to each other.

Rear projector

A projection optical system for projecting, while enlarging, an image formed on an image formation surface onto an image projection surface from an oblique direction relative thereto has at least three optically powered reflective surfaces and a refractive lens surface having a non-rotation-symmetric free-form curved surface and disposed between the first and second reflective surfaces as counted from the image formation surface side.

An projection type image display apparatus includes a projection optical system having a plurality of concave mirrors and digital micromirror device (DMD). An optical path from the DMD to the concave mirror closest to the DMD is a sealed space which is surrounded by an image forming device holding plate holding the DMD, an optical component holding member holding the concave mirror and the image forming device holding plate, and a cover glass (transparent dust-proof cover) arranged on the optical path from the DMD to the concave mirror closest to the DMD.

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Izumiotsu, Japan

Masayuki Imaoka