Casio Computer Co., Ltd.

Other

Etsuro Kawakami

Yasuyuki Tejima

Tetsuro Narikawa

Hiroshi Sato

There is provided a projector unit which can facilitate the design of lenses and project a distortionless and clear image and which comprises a projection optical system in which an optical axis of a projection lens does not coincide with a center of a rectangular image plane of an optical modulator for forming a projected image which corresponds to an image that is projected onto a screen, wherein the optical modulator is disposed in such a manner as to be tilted so that the optical axis of the projection lens and a center normal of the image plane of the optical modulator intersect each other.

Projector unit

A zoom lens of variable power ratio of the order of 3 in which the whole of the zoom lens is made up of three lens elements groups and the power configuration of each of the groups has an arrangement of negative, positive, and negative. The zoom lens includes, sequentially from an object side thereof, a first lens elements group which has a negative refraction power as a whole, a second lens elements group which has a positive refraction power as a whole, and a third lens element group, which has a negative refraction power as a whole. A variable power is realized by shifting the positions of the first and second lens elements group in the direction of an optical axis thereof.

Zoom lens and camera with zoom lens

A high-performance lens system includes lens elements of small diameters for projecting enlarged images from light valves (mainly Digital Micromirror Devices (DMDs))for forming images by changing reflecting directions of light. The lens system includes, sequentially in order from a magnifying side, a first lens group which makes up a substantially afocal optical system as a whole and a second lens group having a positive refractive power as a whole. Depending on the application a third lens group made up of a single positive lens element is provided in the vicinity of the light valve on a contracting side of the second lens group.

Lens system and projector utilizing the same

A high-performance lens system includes lens elements of small diameters for projecting enlarged images from light valves (mainly Digital Micromirror Devices (DMDs)) for forming images by changing reflecting directions of light. The lens system includes, sequentially in order from a magnifying side, a first lens group which makes up a substantially afocal optical system as a whole and a second lens group having a positive refractive power as a whole. Depending on the application a third lens group made up of a single positive lens element is provided in the vicinity of the light valve on a contracting side of the second lens group.

Lens system and projector using the same

To provide a compact, high-performance zoom lens having a small lens aperture for enlarging an image from a light valve such as a DMD for forming an image by changing a reflecting direction of light and projecting the image so enlarged on to a screen or the like, the zoom lens includes, in order from a magnifying side, a first lens group having a negative refractive power as a whole and a second lens group having a positive refractive power as a whole, wherein changing the magnification of a whole lens system thereof is attained by configuring such that while a magnification varying operation is in effect, the first lens group and the second lens group are made to move on the optical axis.

Zoom lens and projector unit

To provide a high performance compact zoom lens with a small lens aperture which projects an image from a light bulb such as a DMD in which an image is formed by changing reflecting directions of light on to a screen or the like in an enlarged fashion, according to the invention, there is provided zoom lens comprising, in order from a magnifying side thereof, a first lens group having a negative refractive power as a whole, a second lens group having a positive or negative refractive power as a whole and a third lens group having a positive refractive power as a whole, wherein changing the magnification of the whole lens system thereof is attained by configuring such that the first lens group and the second lens group are made to move on an optical axis in such a manner as to move in a direction from a magnifying side to a contracting side over a range from a wide angle end to an intermediate area and to move in a direction from the contracting side to the magnifying side over a range from the intermediate area to a telephoto end, and the third lens group is made to move on the optical axis in such a manner as to move in a direction from the contracting side to the magnifying side over a range from the wide angle end to the telephoto end.

Zoom lens and projector using zoom lens

A compact zoom lens which projects an image from a DMD on to a screen in an enlarged scale is provided. There is provided a zoom lens including, in order from a magnifying side, a first lens group having a positive or negative refractive power as a whole, a second lens group having a negative refractive power as a whole, a third lens group having a positive or negative refractive power as a whole, a fourth lens group having a positive refractive power as a whole and a fifth lens group having a positive refractive power as a whole, wherein a variable power as a whole lens system of the zoom lens is established by configuring such that the first lens group and the fifth lens group are left fixed, the second lens group, the third lens group and the fourth group are made to move on an optical axis.

To provide a compact, high-performance zoom lens having a small lens aperture for enlarging an image from a light valve such as a DMD for forming an image by changing a reflecting direction of light and projecting the image so enlarged on to a screen or the like, and a zoom lens so provided includes, in order from a magnifying side, a first lens group having a negative refractive power as a whole, a second lens group having a positive refractive power as a whole, and a third lens group having a positive refractive power as a whole, wherein changing the magnification of a whole lens system thereof is attained by configuring such that while a magnification varying operation is in effect, the third lens group is left fixed, the first lens group and the second lens group are made to move on the optical axis.

There is provided a compact zoom lens having a small lens aperture which an image from a light valve such as a DMD is projected on to a screen in an enlarged scale. There is provided a zoom lens comprising, in order from a magnifying side, a first lens group having a negative refractive power as a whole, a second lens group having a positive or negative refractive power as a whole, a third lens group having a positive refractive power as a whole and a fourth lens group having a positive refractive power as a whole, wherein a variable power as a whole lens system thereof is established by configuring such that the fourth lens group is left fixed while a variable power is effected, and the first lens group, the second lens group and the third lens group are made to move on the optical axis.

To provide a compact, high-performance zoom lens having a small lens aperture for enlarging an image from a light valve such as a DMD for forming an image by changing a reflecting direction of light and projecting the image so enlarged on to a screen or the like, the zoom lens includes, in order from a magnifying side, a first lens group having a positive or negative refractive power as a whole, a second lens group having a negative refractive power as a whole and a third lens group having a positive refractive power as a whole, wherein changing the magnification of a whole lens system thereof is attained by configuring such that while a magnification varying operation is in effect, the first lens group is left fixed, and the second lens group and the third lens group are made to move on the optical axis.

To provide a high performance compact zoom lens with a small lens aperture which projects an image from a light valve such as a DMD (Digital Micromirror Device) in which an image is formed by changing reflecting directions of light on to a screen or the like in an enlarged fashion, according to the invention, there is provided zoom lens comprising, in order from a magnifying side thereof, a first lens group having a positive or negative refractive power as a whole, a second lens group having a negative refractive power as a whole, a third lens group having a positive or negative refractive power as a whole and a fourth lens group having a positive refractive power as a whole, wherein changing the magnification of the whole lens system thereof is attained by configuring such that the first lens group is left fixed while a magnification varying operation is effect, the second lens group, the third lens group and the fourth lens group are made to move on an optical axis.

A high-performance lens system including lens elements of small diameters for projecting on to a screen or the like in an enlarged fashion images from light valves such as mainly DMDs (Digital Micromirror Devices) for forming images by changing reflecting directions of light is provided. A lens system includes, sequentially in that order from a magnifying side, a first lens group which makes up a substantially afocal optical system as a whole and a second lens group having a positive refractive power as a whole, the second lens group being configured to include, sequentially in that order from a magnifying side thereof, a first sub-lens group orlens group having a negative refractive power as a whole and a second sub-lens group orlens group having a positive refractive power as a whole, and depending upon applications, a third lens group made up of a single positive lens element is provided in the vicinity of a light valve such as a DMD on a contracting side of the second lens group.

Growing community of inventors

Akishima, Japan

Etsuro Kawakami