Nikon Corporation

Nippon Telegraph and Telephone Corporation

Sony Corporation

Victor Company of Japan, Limited

Toshiyuki Shimada

Makoto Yamada

Atsushi Mori

Terutoshi Kanamori

Hirotaka Ono

Yasutake Ohishi

Hiroyuki Suzuki

Toshihiro Nishi

Hiroaki Hiratsuka

Provided is a zoom lens (ZL) including, in order from an object along an optical axis: a first lens group (G) having negative refractive power; a second lens group (G) having positive refractive power, and a third lens group (G) having a positive refractive power. At least the first lens group (G) and the second lens group (G) are moved along the optical axis upon zooming from a wide-angle end state to a telephoto end state, so that the distance between the first lens group (G) and the second lens group (G) decreases, and the distance between the second lens group (G) and the third lens group (G) increases, the first lens (G) includes one positive lens, and the second lens (G) includes one negative lens.

Zoom lens, optical apparatus and manufacturing method for the zoom lens

A zoom lens ZL having, in order from an object: a first lens group Ghaving negative refractive power; a second lens group Ghaving positive refractive power; and a third lens group Ghaving positive refractive power, wherein, upon zooming from the wide-angle end state to the telephoto end state, at least the first lens group Gand the second lens group Gmove along the optical axis so that the distance between the first lens group Gand the second lens group Gdecreases, and the distance between the second lens group Gand the third lens group Gincreases, the lens closest to the object in the second lens group Gis a positive lens, and the object side lens surface of this positive lens is an aspherical surface of which radius of curvature increases in a direction from the optical axis to the periphery of the lens.

Zoom lens, optical apparatus and method for manufacturing zoom lens

A zoom lens includes, in order from an object side along an optical axis: a first lens group Ghaving negative refractive power; a second lens group Ghaving positive refractive power; and a third lens group Ghaving positive refractive power. Upon zooming from a wide-angle end state to a telephoto end state, a distance between the first lens group Gand the second lens group Gvaries, and a distance between the second lens group Gand the third lens group Gvaries, and a given conditional expression is satisfied.

Providing a zoom lens system being compact with high optical performance, an optical apparatus using the same, and a method for zooming the zoom lens system. The system includes, in order from an object along an optical axis, a first lens group Ghaving negative refractive power, a second lens group Ghaving positive refractive power, and a third lens group Ghaving positive refractive power. Upon zooming from a wide-angle end state W to a telephoto end state T, each distance between adjacent lens groups is varied. Given conditional expression is satisfied.

Zoom lens system, optical apparatus and method for zooming the same

A zoom lens system comprising, in order from an object along an optical axis: a first lens group having a negative refractive power; a second lens group having a positive refractive power; and a third lens group having a positive refractive power; the following conditional expression being satisfied:0.6&#x3c;max&#xd7;1&#x3c;1.0where Ymax denotes the maximum image height of the zoom lens system, ft denotes a focal length of the zoom lens system in a telephoto end state, and fdenotes a focal length of the first lens group.

Zoom lens system, optical device with zoom lens system, and method of manufacturing zoom lens system

A zoom lens system having higher optical performance, a wide angle of view, a high zoom ratio, and compactness include, in order from an object, a first group having negative power, a second group having positive power, and a third group having positive power. At least the first and second lens groups are moved upon zooming. The first group has, in order from the object, a negative meniscus lens having a convex surface facing the object, and a positive lens. At least one surface of the negative meniscus lens is an aspherical surface. The second group has, in order from the object, a first positive lens, a second positive lens, a negative lens, and a third positive lens. At least one surface of the first positive lens is an aspherical surface. The third group has one positive lens, and at least one surface thereof is an aspherical surface.

Zoom lens system, imaging apparatus and method for varying focal length

A tellurite glass as a glass material of optical fiber and optical waveguide has a composition of 0<Bi O &lE;20 (mole %), 0&lE;Na O&lE;35 (mole %), 0&lE;ZnO&lE;35 (mole %), and 55&lE;TeO &lE;90 (mole %). The tellurite glass allows an optical amplifier and a laser device that have broadband and low-noise characteristics. In a splicing structure of non silica-based optical fiber (as a first fiber) and a silica-based optical fiber (as a second fiber), optical axes of the first and second optical fibers are held at different angles &thgr; and &thgr; (&thgr; &ne;&thgr; ) respectively from a vertical axis of a boundary surface between their spliced ends, and a relationship between the angles &thgr; and &thgr; satisfies Snell's law represented by an equation of sin &thgr; /sin &thgr; &equals;n /n (where n is a refractive index of the first optical fiber and n is a refractive index of the second optical fiber) at the time of splicing the first and second optical fibers.

Optical fiber splicing structure

Tellurite glass, optical amplifier, and light source

A tellurite glass as a glass material of optical fiber and optical waveguide has a composition of 0<Bi,O,&lE;20 (mole %), 0&lE;Na,O&lE;35 (mole %), 0&lE;ZnO&lE;35 (mole %), and 55&lE;TeO,&lE;90 (mole %). The tellurite glass allows an optical amplifier and a laser device that have broadband and low-noise characteristics. In a splicing structure of non silica-based optical fiber (as a first fiber) and a silica-based optical fiber (as a second fiber), optical axes of the first and second optical fibers are held at different angles &thgr;,and &thgr;,(&thgr;,&ne;&thgr;,) respectively from a vertical axis of a boundary surface between their spliced ends, and a relationship between the angles &thgr;,and &thgr;,satisfies Snell's law represented by an equation of sin &thgr;,/sin &thgr;,&equals;n,/n,(where n,is a refractive index of the first optical fiber and n,is a refractive index of the second optical fiber) at the time of splicing the first and second optical fibers.

A packaging film for wrapping a cubic article by bonding an overlapped portion by heat and by folding and sealing open ends of the packaging film, a first non-bonded portion is provided as a first opener on the overlapped portion by partially leaving the overlapped portion not bonded, the first non-bonded portion has a width which is not larger than that of the overlapped portion, the first non-bonded portion is an upper layer of the overlapped portion, and a second non-bonded portion is provided by partially leaving the overlapped portion not bonded, the second non-bonded portion is connected continuously to the first non-bonded portion and has a narrower width than that of the first non-bonded portion, and a second opener is provided on a overlapped portion, the second opener is a lower layer of the overlapped portion and is exposed when the first opener is lifted.

Easily removable packaging film

An optical data storage medium, comprising; (a) an amorphous matrix; and (b) guest molecules dispersed in the amorphous matrix, the guest molecules consisting essentially of electron donors and electron acceptors which are in a solid state at room temperature, the optical data storage medium having an inhomogeneously broadened absorption band due to a distribution of local environments around the guest molecules dispersed in the amorphous matrix, such that the optical data storage medium is capable of storing at least two bits of data in a frequency domain by virtue of an irreversible multiphotonic electron transfer reaction consisting of more than one photon process, in which at least one electron is transferred from the electron donors to the electron acceptors.

Optical storage medium and storage process

Successive n-bit information words are converted into successive m-bit NRZI code words by assigning to each n-bit information word at least one m-bit code word having a respective NRZI disparity. The digital sum variation of the preceding m-bit NRZI code words is determined and the polarity of the conclusion of the immediately preceding m-bit NRZI code word is detected. An assigned m-bit code word is selected to represent the next n-bit information word as a function of the NRZI disparity of that code word, the determined digital sum variation and the detected polarity. The selected m-bit code word then is modulated in NRZI format such that the modulated code word has the same initial polarity as the detected polarity. The m-bit code word is selected such that its NRZI disparity, when combined with the determined digital sum variation, tends to prevent the digital sum variation from increasing.

Method and apparatus for encoding an NRZI digital signal with low DC

A method and apparatus are provided for encoding an n-bit information word into an m-bit code word, n.gtoreq.2 and m&gt;n, wherein the DC component of successive code words is minimized. The digital sum variation (DSV) of a plurality of preceding m-bit code words is used to determine which of, for example, two m-bit code words should be generated to represent the n-bit information word to be encoded. The m-bit code word whose disparity, when combined with the digital sum variation, reduces the digital sum variation towards zero is selected.

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Tokyo, Japan

Toshiyuki Shimada