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| Number | Title | Issue Date |
| 4976522 | Objective lens system for endoscopes An objective lens system comprising, in the order from the object side, a first lens group having negative refractive power and a second lens group having positive refractive power, and so adapted as to perform variation of focal length and focusing by sh... | 12/11/1990 |
| 4973143 | Zoom lens system A zoom lens system having a wide field angle, a long back focal length, a high zooming ratio, and comprising a small number of lens elements. Said zoom lens system comprises, in the order from the object side, a front lens unit having negative refractive ... | 11/27/1990 |
| 4963005 | Zoom lens having built-in diaphragm A zoom lens comprising, from front to rear, a first lens unit of negative power and a second lens unit of positive power, both lens being axially moved to effect zooming, in which a diaphragm is arranged between the first and second lens units to remain s... | 10/16/1990 |
| 4925280 | Vari-focal lens system A compact, light-weight vari-focal lens system manufacturable at low cost comprising a negative front lens group and a positive rear lens group, said front lens group consisting of a first positive lens unit and a second lens unit having a vari-focal func... | 05/15/1990 |
| 4909613 | Zoom lens A zoom lens comprises a front lens group having a positive focal length and a rear lens group having a negative focal length, with the distance between the front and rear lens groups being variable for varying the magnification of the zoom lens. The front... | 03/20/1990 |
| 4909615 | Zoom lens system for use in an image projecting apparatus with kohler illumination A zoom lens system for use in an image projecting apparatus with Kohler illumination in which an image on an object plane is enlargingly projected by the zoom lens system to an image plane apart from the object plane at a definite distance. The zoom lens ... | 03/20/1990 |
| 4906078 | Variable magnification viewfinder A variable magnification viewfinder so designed as to correct aberrations favorably and minimize variations of aberrations caused by varying magnification level thereof. The variable magnification viewfinder comprises an objective lens system and an eyepi... | 03/06/1990 |
| 4890904 | Zoom lens system capable of wide-angle viewing for high zoom ratio A zoom lens system capable of wide-angle viewing for a high zoom ratio has four lens groupss, all of which change the focal length of the overall system while the position of the image plane is held constant. The second lens group comprises a negative len... | 01/02/1990 |
| 4846562 | Zoom lens system A zoom lens system of a relatively high zoom ratio about 2.5 to 3.5 ranging to a wide field angle such as 76 degrees is disclosed. The zoom lens system comprises, from the object to the image side, a first movable negative lens group, a second movable pos... | 07/11/1989 |
| 4844599 | Compact and high-speed wide-angle zoom lens system A wide angle zoom lens system having a high level of brightness includes a zooming subsystem comprising first and second movable lens units and a fixed third lens unit. The first lens unit has at least one aspherical lens surface. In the preferred embodim... | 07/04/1989 |
| 4844600 | Zoom lens system A zoom lens system with a focusing system other than a front group focusing system is provided. The lens system comprises a first lens group including at least two sub-groups with a variable air space therebetween to be varied during zooming, and a focusi... | 07/04/1989 |
| 4838668 | Zoom lens A zoom taking lens for a photographic single lens reflex (SLR) camera. The lens has an air space between elements of the lens, which air space is large enough to accommodate reflective means for directing rays which have passed through elements of the len... | 06/13/1989 |
| 4828372 | Wide-angle zoom lens A compact wide-angle zoom lens with short back focus comprises a forwardmost negative power lens unit movable for focusing and compensation during zooming, followed by a positive power variator lens unit comprising a forward positive power lens sub-unit m... | 05/09/1989 |
| 4807982 | Lens system of variable magnification range and having a supplementary lens unit A zoom lens comprising, from front to rear, a first lens unit of negative refractive power and a second lens unit of positive refractive power, in which either by moving the second lens unit forward to vary the magnification from the wide angle side to th... | 02/28/1989 |
| 4781446 | Zoom lens having a capability of introducing special features into image formats A zoom lens having a plurality of lens units with the air separations, at least one of which is varied to effect zooming, the rearmost lens surface of successive two of the lens units and the frontmost lens surface of the rear one being both formed to con... | 11/01/1988 |
| 4759617 | Zoom lens system A zoom lens system of a relatively high zoom ratio about 2.5 to 3.5 ranging to a wide field angle such as 76 degrees is disclosed. The zoom lens system comprises, from the object to the image side, a first movable negative lens group, a second movable pos... | 07/26/1988 |
| 4730906 | Bright wide-angle zoom lens A compact and high-performance bright wide-angle zoom lens comprising, in order from the object side, a front group having a negative refractive power and a rear group having a positive refractive power, with a stop diaphragm being disposed between the fr... | 03/15/1988 |
| 4726666 | Two-group zoom lens A zoom lens is known which has a first lens group having a negative refracting power and a second lens group having a positive refracting power arranged from an object side, a spacing between both the lens groups being varied to thereby vary magnification... | 02/23/1988 |
| 4711534 | Zoom lens able to obtain focal lengths beyond the zooming range A zoom lens including, from front to rear, a first lens unit of negative power and a second lens unit of positive power with the separation therebetween being varied to effect zooming. The first lens unit is moved to effect focusing, wherein with the firs... | 12/08/1987 |
| 4662723 | Flare stop for a large aperture ratio zoom lens system A flare stop for a large aperture ratio zoom lens system comprising a diverging lens group and a converging lens group and arranged to be zoomed by moving the diverging lens group and converging lens group along the optical axis so that the airspace betwe... | 05/05/1987 |
| 4647160 | Small-sized wide angle zoom objective A small-sized wide angle zoom objective comprising, from front to rear, a 1st lens unit of negative power, a 2nd lens unit of positive power and a 3rd lens unit, wherein the 1st and 2nd units are made axially movable to effect zooming.... | 03/03/1987 |
| 4603948 | Large-aperture wide-angle zoom lens system A large-aperture wide-angle zoom lens system designed for a field angle of 73° to 48° and F/2.8, and having favorably corrected aberrations. Said zoom lens system comprises a front diverging lens group and a rear converging lens group, and is designed f... | 08/05/1986 |
| 4591235 | Zoom lens system A zoom lens system of a relatively high zoom ratio about 2.5 to 3.5 ranging to a wide field angle such as 76 degrees is disclosed. The zoom lens system comprises, from the object to the image side, a first movable negative lens group, a second movable pos... | 05/27/1986 |
| 4586793 | Zoom lens A zoom lens having a lst lens component of negative power counting from front, and a 2nd lens component of positive power, with an air separation therebetween being varied to effect zooming, wherein said 2nd component is divided into two components one of... | 05/06/1986 |
| 4571031 | Wide angle zoom objective A wide angle zoom objective has three lens units of which the first counting from front is of negative power, the second is of positive power and the third is of negative power. At least one lens surface in the first unit has an aspheric surface, and the ... | 02/18/1986 |
| 4540249 | Wide angle zoom lens A wide angle zoom lens comprising, in succession from the object side, a divergent lens group and a convergent lens group and in which magnification change is effected by relative movement of the two groups is characterized in that the divergent lens grou... | 09/10/1985 |
| 4477153 | Ultrawide angle zoom objective Disclosed is a two-component zoom objective having a first lens component of negative power and a second lens component of positive power with the variable air separation between the first and second components effecting zooming. The aforesaid first lens ... | 10/16/1984 |
| 4465343 | Zoom lens system The present invention is directed to a three-group type wide angle zoom lens system which comprises, from the object to the image side, a first lens group of a negative refractive power movable along the optical axis for zooming, the first lens group incl... | 08/14/1984 |
| 4447135 | Zoom lens system An improved wide angle zoom lens system of an inverted telephoto type having a negative object side lens group and a positive image side lens group is provided, in which an air space to be varied in accordance with the shift of the object side lens group ... | 05/08/1984 |
| 4406523 | Compact wide-angle zoom lens A high performance compact wide angle zoom lens, composed, in order from the object side, of a divergent front lens group and a convergent rear lens group, wherein the front and rear lens groups are moved mechanically to thereby vary the overall focal len... | 09/27/1983 |
| 4364641 | Wide angle zoom lens This specification discloses a zoom lens which comprises, in succession from the object side, a divergent lens group and a convergent lens group and whose magnification is changed by relative movement of the two groups. The divergent lens group comprises,... | 12/21/1982 |
| 4329022 | Two group type zoom lens with wide image angle The disclosed two-group wide-image-angle zoom lens is zoomed by changing the distance between the front and the rear group. The front group exhibits a negative refracting power and includes a first positive lens, a second negative lens concave toward the ... | 05/11/1982 |
| 4315669 | Wide-angle zoom lens system A wide-angle zoom lens system consisting of a front lens group, a rear lens group and an aperture stop arranged therebetween, said front lens group comprising a first positive meniscus lens element having a convex surface on the object side, a second nega... | 02/16/1982 |
| 4198127 | Wide angle zoom lens system having small distortion The present invention provides a compact zoom lens which exhibits small distortion aberration. The lens system comprises, in order from the object side, a front lens group having a negative focal length and a rear lens group having a positive focal length... | 04/15/1980 |
| 4196968 | Wide angle zoom lens system A miniaturized, super-wide angle zoom lens system of the two lens group type wherein barrel shaped distortion aberration in the wide angle position is compensated for by providing one of the lenses with an aspherical surface.... | 04/08/1980 |
| 4196969 | Zoom lens having a small distortion aberration The present invention provides a compact zoom lens which exhibits only small distortion aberration. The present invention comprises, in order from the object side, a first lens group having a negative focal length, a second lens group having a positive fo... | 04/08/1980 |
| 4190323 | Wide angle zoom lens with high zoom ratio A two lens group type of miniaturized zoom lens system having a minimum wide end viewing angle of 76° and a zoom ratio at least 2.3. The first or object side lens group includes at least two positive and two negative lenses with the image side lens being... | 02/26/1980 |
| 4189212 | Wide angle zoom lens system In a wide angle zoom lens system comprising a diverging lens group and a converging lens group which are both movable on the optical axis of the lens system to vary the air space between the two groups so that the magnification of the image is variable wh... | 02/19/1980 |
| 4172635 | Zoom lens system A wide angle zoom lens system having a front lens group of a positive refractive power with an extended zoom ratio. A second lens group is located adjacent the first lens group and has sufficient negative refractive power so that the combined refractive p... | 10/30/1979 |
| 4169660 | Wide-angle zoom lens system The wide-angle zoom lens system comprises a divergent lens group and a convergent lens group in the order from the object side, both of the lens groups being movable on the optical axis of the lens system to vary the air space between the two groups so th... | 10/02/1979 |
