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| Number | Title | Issue Date |
| 7324293 | Wide-angle lens system A wide-angle lens system includes a negative front lens group and a positive rear lens group, in this order from the object. The negative front lens group includes a negative first sub-lens group and a positive second sub-lens group, in this order from the ob... | 01/29/2008 |
| 7317581 | Fisheye lens system and a fisheye zoom lens system A fisheye lens system includes a negative first lens group and a positive second lens group, which are defined with respect to a maximum air-distance between lens elements constituting the fisheye lens system. The negative first lens group includes a first negative ... | 01/08/2008 |
| 7209300 | Wide-angle lens system A wide-angle lens system includes a positive front lens group, a diaphragm, and a positive rear lens group. The front lens group includes a negative first-sub-lens group and a positive second-sub-lens group. The negative first-sub-lens group includes a negati... | 04/24/2007 |
| 7173776 | Fisheye lens system A fisheye lens system with a half angle-of-view of 90° includes a negative front lens group, a diaphragm, and a positive rear lens group. The negative front lens group includes at least three negative meniscus lens elements each of which has the convex surfa... | 02/06/2007 |
| 6603610 | Wide-angle lens system A wide-angle lens system includes a negative first lens group, and a positive second lens group. The first lens group includes a positive lens element, and a negative lens element. The wide-angle lens system satisfies the following conditions: 0 | 08/05/2003 |
| 6545824 | Wide-angle lens system The improved inner-focus, wide-angle lens system of retrofocus configuration comprises, in order from the object side, a negative first lens group 10, a positive second lens group 20, and a positive third lens group 30 having a diaphragm; the second lens ... | 04/08/2003 |
| 6493157 | Image-capturing lens An image-capturing lens is formed of front and rear lens groups having negative and positive refractive power, respectively, in order from the object side. The rear lens group is formed of, in relative sequential order from the most object side of the rea... | 12/10/2002 |
| 6275343 | Projection optical system A projection optical system has, from the enlargement side to the reduction side, a first, a second, and a third lens unit, and an aperture diaphragm. The negatively-powered first lens unit includes only a negative lens element and has at least one aspher... | 08/14/2001 |
| 6181477 | Imaging lens In an imaging lens unit configured of two lenses, the deterioration of the optical performance due to the eccentricity is suppressed for an improved assembling property, while at the same time correcting the various aberrations in satisfactory manner. A m... | 01/30/2001 |
| 6160671 | Retro-focus lens A retro focus lens having three lens groups arranged, in order from the longer conjugate length side of the lens, as follows: a negative first lens group G1, a positive second lens group G2, and a positive third lens group G3. | 12/12/2000 |
| 5920436 | Large-aperture lens for low-illuminance imaging In a large-aperture lens for low-illuminance imaging, a Gauss type lens configuration is employed, and a negative lens having a predetermined refracting power is inserted in front of the front-side cemented lens, whereby back focus is secured while compac... | 07/06/1999 |
| 5914823 | Camera lens systems In an image forming optical lens system comprising in order from the object end a first lens group of at least two components, a second lens group which has a positive focal length and comprises in order from the object end a first component of positive p... | 06/22/1999 |
| 5812326 | Wide angle lens A wide angle lens is made of three groups so as to satisfy a predetermined conditional expression concerning abbe number, thereby making it telecentric and yielding no eclipse in its peripheral luminous flux. Also, an apparatus accommodating it is made co... | 09/22/1998 |
| 5796529 | Fast photographic lens system A fast photographic lens system comprises a first lens having a positive refractive power, a convex-shaped outer face and a flat inner face; a second lens having a positive refractive power, a convex-shaped outer face and a concave-shaped inner face; a th... | 08/18/1998 |
| 5790324 | Wide-angle photographic lens system A compact wide-angle photographic lens system of a retrofocus type includes, from the object side, a first, a sixth, and a seventh meniscus lens group of positive refractive powers, a second and a third meniscus lens group of negative refractive powers, a... | 08/04/1998 |
| 5724191 | Enlarging lens with a large working distance An enlargement lens system with a large working distance comprising five lens components with a stop between the third and fourth components (numbered from the long conjugate side). It includes a first negative lens component, meniscus concave to the stop... | 03/03/1998 |
| 5684643 | Fast wide-angle lens system A wide-angle fast lens system includes a front lens group having a negative power, a diaphragm and a rear lens group having a positive power. The front lens group consists of a first sub-lens group and a second sub-lens group having a negative power. The ... | 11/04/1997 |
| 5668669 | Compact wide-angle objective lens A wide-angle objective lens is comprised, from the object side, of a first lens component which is a negative meniscus lens having its convex surface facing the object side, a second lens component which is a meniscus lens having its convex surface facing... | 09/16/1997 |
| 5625497 | Retrofocus type standard lens and wide angle lens A retrofocus type standard lens includes a front lens group having a positive power, a diaphragm, and a rear lens group having a negative power, in this order from the object side. The focusing is carried out by moving the front lens group without moving ... | 04/29/1997 |
| 5621575 | Wide angle lens system In a wide range of photographing from long shot to close-up, high resolving power and high contrast can be obtained in a wide angle lens system. The wide angle lens system comprises, successively from the object side, a negative meniscus first lens (L1), ... | 04/15/1997 |
| 5589988 | Retrofocus-type wide angle lens system having a fixed front lens group and a movable rear lens group A wide angle lens system comprises a front lens group and a rear lens group having positive refractive power. The front lens group includes in the order from the object side, a negative meniscus lens component having a convex surface facing the object sid... | 12/31/1996 |
| 5557472 | Fast aspherical lens system A fast lens system is provided which includes a front lens group having a negative power, a diaphragm, and a rear lens group having a positive power, arranged in this order from a side of an object of the lens system. The lens system satisfies the followi... | 09/17/1996 |
| 5477388 | Inverse telescopic wide angle lens An inverse telescopic wide angle lens comprises a diaphragm; a front lens group of an integral positive or negative refractive power, positioned in the object side in front of the diaphragm and having a first lens group of a negative refractive power incl... | 12/19/1995 |
| 5278698 | Magnifying projecting lens A magnifying projecting lens has a negative first lens group, a positive second lens group and a positive third lens group that is arranged in this order from a magnifying side. The lens groups are arranged so as to satisfy the following condition: fb/f>1... | 01/11/1994 |
| 5218480 | Retrofocus wide angle lens A wide angle lens system of the retrofocus type is provided which includes two lens units. The first lens unit is of negative power and includes a combination of a positive element having a high dispersion and a negative element having a low dispersion fo... | 06/08/1993 |
| 4806003 | Inverted-telephoto type wide angle lens system An inverted-telephoto type wide angle lens system is provided which comprises from the object side to the image side: a first lens group of a negative refractive power; a second lens group of a positive refractive power; an aperture diaphragm; and a third... | 02/21/1989 |
| 4759619 | Inverted telephoto type wide angle lens system with a rear focusing unit An improvement of an inverted telephoto type wide angle lens system having, from the object to the image side a front lens group of a negative refractive power which is left stationary upon focusing, and a rear lens group of a positive refractive power wh... | 07/26/1988 |
| 4747676 | Wide-angle seven-element lens system A wide-angle lens system of the seven-unit-seven-element configuration. Arranged in ordered from the object side are two opposed negative meniscus lenses, two opposed positive lenses, a negative lens and two lens with opposed convex surfaces. Four require... | 05/31/1988 |
| 4720183 | Extreme wide angle eyepiece with minimal aberrations A wide-angle eyepiece designed to cover a field of view of 90° with substantially perfect correction of spherical aberration, coma, astigmatism, field curvature, chromatic aberration, and spherical aberration of the exit pupil.... | 01/19/1988 |
| 4660940 | Small-sized wide-angle lens A retro-focus type wide-angle lens which has a large angular field of 76° to 90° and secures a sufficient amount of corner illumination comprises only five sets of lens elements including eight or nine lens elements. The first set of convergent lens loc... | 04/28/1987 |
| 4333714 | Compact wide angle lens A retrofocus lens having a field angle of up to 76° and comprising as few as six elements. A strongly negative front group of only two elements contributes to the compactness of the lens.... | 06/08/1982 |
| 4286847 | Lightweight inverted telephoto type wide angle lens system The present invention is directed to an inverted telephoto type wide angle lens system having eight lens groups and eight lens elements which fulfill the following conditions: wherein f1,2,3 represents the total focal length of the first to third ... | 09/01/1981 |
| 4145117 | Retrofocus type wide angle lens system A retrofocus type wide-angle lens system comprising a first positive meniscus lens, a second negative meniscus lens, a third negative meniscus lens, a fourth biconvex lens, a fifth biconcave lens, a sixth positive meniscus lens and a seventh biconvex lens... | 03/20/1979 |
| 4143945 | Small retro-focus wide angle photographic lens system A retro-focus wide angle photographic lens system comprises a front lens group including first and third negative meniscus lenses each having one surface greater in curvature than the other and oriented toward an image, and a second positive lens, and a r... | 03/13/1979 |
| 4099849 | Wide angle objective This disclosure relates to a Wide Angle Lens of the retrofocus type having a new lens group arrangement which comprises from the object end to the image end a first negative group, a second negative group in the form of a meniscus having a concave image s... | 07/11/1978 |
| 4080048 | Ultra-high resolution reducing lens system An ultra-high resolution reducing lens system comprising a lens group I having negative refractive power and a lens group II having positive refractive power which are arranged by providing a large airspace between them. The ultra-high resolution lens sys... | 03/21/1978 |
| 4062622 | Small size retrofocus wide angle photographic lens A small size, wide angle, retrofocus photographic lens is disclosed consisting of eight lens elements. The lens has a relative aperature of 1:4.0 and a field angle of 94°.... | 12/13/1977 |
| 4046459 | Retrofocus wide angle objective lens system A retrofocus wide angle objective lens system of seven air-spaced lenses, the first and second lenses, counting in the order of the entrant light beam, being negative meniscus lenses of forward convexity, the third lens being a positive lens, the fourth l... | 09/06/1977 |
| 4025168 | Wide angle photographic lens A small size wide angle lens having an aperture ratio of 1 : 1.4 is disclosed. The lens consists of seven lens groups arranged to achieve the objects of brightness, small size, large aperture opening, while balancing the aberration.... | 05/24/1977 |
| 4025170 | Retro-focus type wide angle objective lens A retrofocus type wide angle objective lens comprising a negative lens group N and a positive lens group P having a diaphragm therein arranged in this order from the object side, said negative lens group N being constructed from a divergent front lens gro... | 05/24/1977 |
