公开(公告)号：US5900987A

公开(公告)日：1999-05-04

申请号：US22700

申请日：1998-02-12

申请人： Melvyn H. Kreitzer

发明人： Melvyn H. Kreitzer

IPC分类号： G02B15/177 ,  G02B15/14

CPC分类号： G02B15/161 ,  G02B15/177

摘要： A zoom projection lens for use with LCD or DMD panels is provided. The lens has two units U1 and U2, which are moved relative to one another for zooming. The first unit has a negative power and includes at least three lens elements L1, L2, and L3, where L1 is composed of plastic and has two aspherical surfaces, L2 has a positive power and is composed of a flint material, and L3 has a negative power and is composed of a crown material. The second unit has two subunits U2.sub.S1 and U2.sub.S2, each of which has a positive power, with the power of U2.sub.S2 being greater than the power of U2.sub.S1. At its minimum effective focal length f.sub.min, the projection lens has a back focal length to focal length ratio greater than one, the ratio being achieved by arranging the first unit, the second unit, and the subunits of the second unit so that:D.sub.12 /f.sub.min >1.0,D.sub.S1S2 /f.sub.min >1.0,andD.sub.12 /D.sub.S1S2 >1.0,where D.sub.12 is the axial distance between the first and second lens units evaluated at f.sub.min and D.sub.S1S2 is the axial distance between the first and second subunits of the second lens unit.

摘要翻译： 提供与LCD或DMD面板一起使用的变焦投影透镜。 透镜具有两个单元U1和U2，它们相对于彼此移动以进行变焦。 第一单元具有负功率，并且包括至少三个透镜元件L1，L2和L3，其中L1由塑料构成并且具有两个非球面，L2具有正的功率并且由燧石材料构成，并且L3具有 负功率由冠材料组成。 第二单元具有两个子单元U2S1和U2S2，每个子单元具有正功率，U2S2的功率大于U2S1的功率。 在其最小有效焦距fmin处，投影透镜的后焦距与焦距比大于1，该比率通过布置第二单元的第一单元，第二单元和子单元来实现，使得：D12 / fmin> 1.0，DS1S2 / fmin> 1.0和D12 / DS1S2> 1.0，其中D12是在fmin处评估的第一和第二透镜单元之间的轴向距离，DS1S2是第二透镜单元的第一和第二子单元之间的轴向距离 。

公开(公告)号：US4900139A

公开(公告)日：1990-02-13

申请号：US266234

申请日：1988-10-28

申请人： Melvyn H. Kreitzer

发明人： Melvyn H. Kreitzer

IPC分类号： G02B13/16 ,  G02B13/18

CPC分类号： G02B13/16 ,  G02B13/18

摘要： A lens comprising from the image side a first lens unit which is a positive element with at least one aspheric surface; a three element lens unit consisting of a biconcave element, a biconvex element and another positive component, in that order; a third lens unit having a strongly concave image side surface and which serves as a field flattener and to correct the Petzval sum of the lens.

摘要翻译： 一种透镜，包括从图像侧的第一透镜单元，其是具有至少一个非球面的正元件; 一个三元素透镜单元，由双凹点元件，双凸元件和另一个正向分量构成; 第三透镜单元，其具有强凹面的图像侧表面，并且用作场平坦度器，并且校正透镜的彼此之和。

公开(公告)号：USRE32923E

公开(公告)日：1989-05-16

申请号：US659334

申请日：1984-10-10

申请人： Melvyn H. Kreitzer

发明人： Melvyn H. Kreitzer

IPC分类号： G02B15/173

CPC分类号： G02B15/173

摘要： A lens of variable equivalent focal length where two lens groups located on either side of an aperture defining means move relative to the aperture defining means, and a lens group of positive power is positioned close to the aperture defining means. The aperture defining means and the associated positive power group may either be stationary or move with change in equivalent focal length.

公开(公告)号：US4523816A

公开(公告)日：1985-06-18

申请号：US522519

申请日：1983-08-12

申请人： Melvyn H. Kreitzer

发明人： Melvyn H. Kreitzer

IPC分类号： G02B13/18 ,  G02B17/08

CPC分类号： G02B17/0856 ,  G02B17/0808 ,  G02B17/0852 ,  G02B17/0884

摘要： A catadioptric lens where the primary and secondary lenses are fixed in relation to the image plane and focusing of the lens is accomplished by movement of a refractive lens group positioned subsequent to the mirror system in relation to the object end of the lens.

摘要翻译： 主透镜和次透镜相对于图像平面固定并且透镜的聚焦的反折射透镜通过相对于透镜的物体端位于反射镜系统之后的折射透镜组的移动来实现。

公开(公告)号：US4359272A

公开(公告)日：1982-11-16

申请号：US183999

申请日：1980-09-04

申请人： Melvyn H. Kreitzer

发明人： Melvyn H. Kreitzer

IPC分类号： G02B13/02 ,  G02B9/60

CPC分类号： G02B13/02

摘要： A new and improved telephoto lens comprising a stationary front positive group, a movable second group employed for internal focusing, a stationary third positive group and a stationary fourth negative group. The lens has a very low telephoto ratio and a very short focusing motion accompanied by a high degree of aberrational correction, all of which is achieved without the use of crystalline or expensive glass materials.

摘要翻译： 一种新的改进的长焦镜头，包括固定前正极组，用于内部聚焦的可移动第二组，固定第三正极组和固定第四负极组。 透镜具有非常低的长焦比和非常短的聚焦运动，伴随着高度的像差校正，所有这些都是在不使用结晶或昂贵的玻璃材料的情况下实现的。