Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Matsushita Electric Industrial Co., Ltd.

Katsu Yamada

Takuya Imaoka

Keiki Yoshitsugu

Kazuhiko Ishimaru

Yoshito Miyatake

Kyoichi Miyazaki

Shusuke Ono

Tsuneo Uchida

Masaki Sampei

Satoshi Kuzuhara

Shunichiro Yoshinaga

Qinghua Zhao

Hiroaki Okayama

Shinji Yamaguchi

Hideo Onishi

Tsutomu Iwashita

Kenji Ikeo

Tsuyoshi Kakimoto

Michihiro Yamagata

Yasuhiro Tanaka

Yoshiharu Yamamoto

Motonobu Yoshikawa

Yoshio Matsumura

Kazutake Boku

Keizo Ishiguro

Shuusuke Ono

The optical system includes a first sub-optical system including an aperture stop and a second sub-optical system including a prism. The prism has a first transmission surface located on a reduction side, a second transmission surface located on a magnification side, and at least one reflection surface between the first transmission surface and the second transmission surface. The first sub-optical system includes a plurality of rotationally symmetric lens elements. When the axis passing through at least two centers of the rotationally symmetric lens element is defined as a reference optical axis, at least one optical surface of the prism is formed such that in a plane perpendicular to the reference optical axis, a maximum angle θmax and a minimum angle θmin in terms of an angle at which a principal ray of light rays having an image-forming relationship on a concentric circle centered on an intersection of the reference optical axis and a reduction conjugate point of the rectangular region intersects a normal line of the plane at a position where the principal ray is made incident on the optical surface satisfy the following Expression (1): 45°>|θmax|−|θmin|>0.014°.

Optical system, image projection apparatus, and imaging apparatus

The present disclosure is directed to an optical system internally having an intermediate imaging position that is conjugate with both of a magnification conjugate point on a magnification side and a reduction conjugate point on reduction side, including: a magnification optical system including a plurality of lens elements and positioned on the magnification side with respect to the intermediate imaging position; and a relay optical system including a plurality of lens elements and positioned on the reduction side with respect to the intermediate imaging position, wherein the relay optical system includes a plurality of moving lens groups which are independently movable in an optical axis direction during zooming, and wherein the reduction side-closest moving lens group that is positioned closest to the reduction side among the plurality of moving lens groups has a negative refractive power.

The present disclosure is directed to an optical system internally having an intermediate imaging position that is conjugated to a magnification conjugate point on a magnification side and a reduction conjugate point on a reduction side, respectively, the optical system comprising: a magnification optical system positioned on the magnification side with respect to the intermediate imaging position; and a relay optical system positioned on the reduction side with respect to the intermediate imaging position; the relay optical system including: a first lens group positioned closest to the magnification side; two lens groups positioned on the reduction side with respect to the first lens group; and a negative lens group interposed between the two lens groups, wherein during zooming the negative lens is fixed, while the two lens groups are displaced.

The present disclosure is directed to an optical system internally having an intermediate imaging position that is conjugate to magnification and reduction conjugate points, respectively, the optical system including: a magnification optical system having a plurality of lens elements, positioned on the magnification side with respect to the intermediate imaging position; and a relay optical system having a plurality of lens elements, positioned on the reduction side with respect to the intermediate imaging position, wherein there are a plurality of air distances among the lens elements, the magnification optical system includes a magnification optical system front group positioned on the magnification side with respect to the longest air distance in the magnification optical system and a magnification optical system rear group positioned on the reduction side with respect to the longest air distance, and the optical system satisfies the conditions (1) and (2).

An optical system according to the present disclosure includes a first sub-optical system including an aperture stop and a second sub-optical system including a prism. The prism has a first transmission surface located on the reduction side, a second transmission surface located on the magnification side, and at least one reflection surface located on the optical path between the first transmission surface and the second transmission surface. A first reflection surface closest to the intermediate imaging position has a shape with a concave surface facing a direction into which a light ray incident on first the reflection surface is reflected. A curvature shape of the first reflection surface is set such that some of multiple principal rays passing through the reduction conjugate point intersect on the optical path between the first reflection surface and the second transmission surface.

A projection lens system projects an image of a reduction side into a magnification side in an image projection device, a back glass being disposed on the reduction side. In the projection lens system, all of one or more negative lenses that satisfy, in a surface on the reduction side or a surface on the magnification side, condition |h/H|&#x3c;2.0 defined by height h of a most off-axis principal ray and height H of an axial ray passing through a highest pupil position satisfy conditions Tn&#x2265;98.5% and Dn/Db&#x2264;0.05 defined by transmittance Tn, thickness Dn of the negative lens on an optical axis, and total thickness Db of the back glass.

Projection lens system and image projection device

A projection lens system that projects an image of a reduction side into a magnification side includes a diaphragm, a plurality of positive lenses, and a plurality of negative lenses. The plurality of positive lenses include a first positive lens closer to the magnification side than the diaphragm is and closest to the diaphragm, a second positive lens second closest to the diaphragm after the first positive lens on the magnification side, a third positive lens closer to the reduction side than the diaphragm is and closest to the diaphragm. The plurality of negative lenses include a first negative lens closer to the magnification side than the diaphragm is and closest to the diaphragm, and a second negative lens closer to the reduction side than the diaphragm is and closest to the diaphragm. The lenses have transmittances larger than threshold values, respectively.

An image projection device includes an image display element that forms a projection image, a transmissive optical system that is disposed on an emission surface side of the image display element and includes a diaphragm and a plurality of lenses, and a reflection optical system that includes a first mirror reflecting light emitted from the transmissive optical system and having positive power and a second mirror that is a plane mirror for reflecting light reflected by the first mirror on a projection surface. The first mirror is disposed between the second mirror and the projection surface in a direction along an optical axis of the transmissive optical system. An intermediate image is formed between the transmissive optical system and the first mirror.

Image projection device

A projection optical system is a projection optical system for projecting an image in an image display element on a projection target surface in an enlarged manner, and includes a transmissive optical system and a reflection optical system. The transmissive optical system includes a plurality of lenses and an aperture diaphragm. The reflection optical system includes a first reflecting surface that reflects light emitted from the transmissive optical system and a second reflecting surface that reflects light emitted from the first reflecting surface. A principal ray of the reference rays is a ray passing through a center of the aperture diaphragm among the reference rays. Local power of the first reflecting surface at a position where the principal ray enters the first reflecting surface is larger than local power of the second reflecting surface at a position where the principal ray enters the second reflecting surface.

Projection optical system, image projection device and image projection system

A projection optical system is an optical system for projecting an image light flux formed in an image display element onto a projection surface, and includes a transmission optical system and a reflection optical system. The transmission optical system is located on an emission surface side of the image display element and includes a stop and a plurality of lenses. The reflection optical system includes a positive-power first mirror and a second mirror. Conditional Expression (1) is satisfied0&#x3c;&#x3c;10&#x2003;&#x2003;(1)where

Projection optical system and image projection device for projecting an image light flux onto a projection surface

A projection optical system projects onto a projection surface an image ray bundle formed on an image display element, and includes a transmissive optical system positioned on a side of an emission surface of the image display element and having 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 at least one positive lens disposed closer to the image display element than an aperture stop, along with first and second positive lenses having a meniscus shape, and a negative lens disposed therebetween, which are closer to the projection surface than the aperture stop is. During focusing, spacing between the first positive lens and the negative lens and spacing between the second positive lens and the negative lens remain unchanged.

Projection optical system and image projector

A zoom lens system comprising: a first lens unit having negative optical power; a second lens unit having positive optical power; and a third lens unit having positive optical power, wherein the first to third lens units are individually moved along an optical axis to vary magnification in zooming, each lens unit includes at least one lens element that satisfies the conditions: nd&#x2266;1.67, vd&#x3c;59 and 0.000&#x3c;PgF+0.002&#xd7;vd&#x2212;0.664 (nd, vd and PgF: a refractive index to the d-line, an Abbe number to the d-line and a partial dispersion ratio, of the lens element), and the condition: 0.31&#x3c;Ir/&#x221a;(|f&#xd7;f|) (Ir=f&#xd7;tan(&#x3c9;), fand &#x3c9;: a focal length of the entire system and a half value of maximum view angle, at a telephoto limit, fand f: a focal length of each of the first lens unit and the second lens unit) is satisfied; an imaging device; and a camera are provided.

Zoom lens system, imaging device and camera

A zoom lens system comprising: a negative first lens unit; a positive second lens unit; and a positive third lens unit, wherein the first to third lens units are individually moved along an optical axis to vary magnification in zooming, the first lens unit is composed of two lens elements and includes a positive lens element having at least one aspheric surface, the third lens unit is composed of one lens element, and the condition: 1.74&#x3c;Ir/&#x221a;{square root over ((|D&#xd7;f|))} (D: an optical axial thickness of an object side first lens element in the first lens unit, f: a focal length of the first lens unit, Ir=f&#xd7;tan(&#x3c9;), fand &#x3c9;: a focal length of the entire system and a half value of maximum view angle at a telephoto limit) is satisfied; an imaging device; and a camera are provided.

A zoom lens system is provided that includes a compactly constructed focusing lens unit and that has a suppressed change in the image magnification at the time of movement of a focusing lens unit. The zoom lens system according to the present invention comprises a plurality of lens units and an aperture diaphragm arranged in the lens unit. The plurality of lens units include a focusing lens unit that is arranged on an object side relative to the aperture diaphragm and that moves in a direction along the optical axis at the time of focusing. Further, the zoom lens system satisfies at least one of the following conditions: (1) 1.2&#x3c;|f/f|&#x3c;6.0; and (2) 0.10&#x3c;|f/f|&#x3c;1.8 (here, f/f&#x3e;3.0, f: a focal length of the focusing lens unit, f: a focal length of the entire system at a telephoto limit, f: focal length of the entire system at a wide-angle limit).

Zoom lens system, interchangeable lens apparatus and camera system

A zoom lens system according to the present invention, from an object side, comprises a first lens unit having positive optical power, a second lens unit having negative optical power, a third lens unit having positive optical power, and a fourth lens unit having positive optical power. In zooming, the first to the fourth units all move along the optical axis. The third lens unit is composed of three or more lens elements. The condition (6): nd&#x2266;1.5 and vd&#x2267;75 and the condition (7): (nd&#x2212;1)+(nd&#x2212;1)&#x2267;1.55 are satisfied (where, 16&#x3c;f/f, &#x3c9;&#x3e;35, and in the third lens unit: nd, nd, ndare refractive indices to the d-line of the lens elements located on the most object side and at the second and the third positions from the object side; vdis an Abbe number to the d-line of the lens element on the most object side; &#x3c9; is a half view angle at a wide-angle limit; fis a focal length of the entire system at a telephoto limit; and fis a focal length of the entire system at a wide-angle limit). As a result, the zoom lens system has a reduced size and still realizes a wide view angle at a wide-angle limit, as well as a remarkably high zooming ratio and high performance.

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Osaka, Japan

Katsu Yamada