US3877783A
Expired / Lapsed
US
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Gradient refractive index light-conducting glass structure
Assignee: Nippon Selfoc Co Ltd
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Filing: 1969-09-26
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Granted: 1975-04-15
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Expires: 1989-09-26
Abstract
Abstract A light-conducting glass structure, the refractive index of which in each cross section perpendicular to the centre line or plane along which light is to advance of the structure decreases progressively from the centre line or plane toward the outer surface of the structure, and the rate of decreasing the refractive index is smaller at the vicinity of at least either end surface being transverse to the centre line or plane than that in the other part of the glass structure. The decrease of refractive index occurs by varying the concentration within the glass structure of at least two kinds of cations (They differ from each other in their contributions to increasing of refractive index.) constituting modifying oxides. The rate of decreasing refractive index at the vicinity of at least either end surface of the glass structure is made to carry out by such a manner that the cation within the glass structure (Which is either of at least two kinds of cations mentioned above and has higher contributions to the increase of refractive index than that of the other.) is substituted by another cation from an external cation source in a greater extent, or a stretching ratio of a part to be an end surface of the glass structure having a certain rate of decreasing refractive index is adjusted to be smaller.
Inventors
- 👤 Hiroyoshi Matsumura
- 👤 Seiichi Ono
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:59
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/02; G02B6/028; G02B6/0281; C; C03; C03B; C03B37/00; C03B37/01; C03B37/02; C03B37/022; C03B37/023; C03B37/025; C03B37/027; C03B37/02718; C03B37/029; C03C; C03C21/00; C03C21/001; C03B2201/00; C03B2201/06; C03B2201/30; C03B2201/50; C03B2203/00; C03B2203/02; C03B2203/06; C03B2203/10; C03B2203/22; C03B2205/00; C03B2205/02; C03B2205/55; C03B2205/56
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
261 words
A light-conducting glass structure having a predetermined refractive index and focusing effect comprising an elongated glass body having a center axis and having entrance and exit surfaces for light, both transverse to said center axis, and a side surface encompassing said center axis; said glass body having at least two kinds of cation means constituting glassmodifying oxides, wherein said at least two kinds of cation means are different in contribution to the refractive index of the glass and are ion-exchangeable with each other, and wherein the concentration within the glass of at least one of said cation means progressively decreases from said center axis toward said side surface and the concentration within the glass of at least one kind of remaining cation means progressively increases from said center axis toward said side surface; and said glass body having a refractive index gradient which is due to said concentration gradients, wherein said refractive index gradient produces said focusing effect, and is substantially expressed, at least in the vicinity of said center axis in each planar cross section perpendicular to said center axis, by the following equation: n no (1 - ar2) wherein no represents the refractive index of the glass at said center axis, n represents the refractive index at a distance r from said centEr axis, and a is a positive constant at the planar cross section, said positive constant being such that the value thereof increases from at least one surface of said entrance and exit surfaces for light toward the inside of the glass body along said center axis.
Claim 2
Dependent Claim
261 words
A light-conducting glass structure having a predetermined refractive index and focusing effect comprising an elongated glass body having a center axis and having entrance and exit surfaces for light, both transverse to said center axis, and a side surface encompassing said center axis; said glass body having at least two kinds of cation means constituting glassmodifying oxides, wherein said at least two kinds of cation means are different in contribution to the refractive index of the glass and are ion-exchangeable with each other, and wherein the concentration within the glass of at least one of said cation means progressively decreases from said center axis toward said side surface and the concentration within the glass of at least one kind of remaining cation means progressively increases from said center axis toward said side surface; and said glass body having a refractive index gradient which is due to said concentration gradients, wherein said refractive index gradient produces said focusing effect, and is substantially expressed, at least in the vicinity of said center axis in each planar cross section perpendicular to said center axis, by the following equation: n no (1 - ar2) wherein no represents the refractive index of the glass at said center axis, n represents the refractive index at a distance r from said centEr axis, and a is a positive constant at the planar cross section, said positive constant being such that the value thereof increases from at least one surface of said entrance and exit surfaces for light toward the inside of the glass body along said center axis.
Claim 3
Dependent Claim
34 words
A light-conducting glass structure as claimed in claim 1 in which one kind of said cation means comprises ions of thallium and another kind of said cation means comprises ions of an alkali metal.
Claim 4
Dependent Claim
279 words
A light-conducting glass structure having a predetermined refractive index and focusing effect comprising an elongated glass body having entrance and exit surfaces for light both transverse to said center axis and a side surface encompassing said center axis; said glass body having at least two kinds of cation means constituting glass-modifying oxides, wherein said at least two kinds of cation means differ in their contribution to the refractive index of the glass and are ion-exchangeable with each other, and wherein the concentration within the glass of at least one kind of cation means progressively decreases from said center axis toward said side surface and the concentration within the glass of at least one kind of remaining cation means progressively increases from said center axis toward said side surface; and said glass body having a refractive index gradient which is due to said concentration gradients, wherein said refractive index gradient produces said focusing effect, and is substantially expressed, at least in the vicinity of said center axis in each planar cross section perpendicular to said center axis, by the following equation; n no (1 - ar2) wherein no represents the refractive index of the glass at said center axis, n represents the refractive index at a distance r from said center axis, and a is a positive constant at the planar cross section, said positive constant being such that the value thereof progressively increases from one surface toward the other surface of said entrance and exit surfaces for light, and wherein the diameter of said planar cross section perpendicular to said center axis decreases from said one surface toward said other surface of said entrance and exit surfaces for light.
Claim 5
Dependent Claim
279 words
A light-conducting glass structure having a predetermined refractive index and focusing effect comprising an elongated glass body having entrance and exit surfaces for light both transverse to said center axis and a side surface encompassing said center axis; said glass body having at least two kinds of cation means constituting glass-modifying oxides, wherein said at least two kinds of cation means differ in their contribution to the refractive index of the glass and are ion-exchangeable with each other, and wherein the concentration within the glass of at least one kind of cation means progressively decreases from said center axis toward said side surface and the concentration within the glass of at least one kind of remaining cation means progressively increases from said center axis toward said side surface; and said glass body having a refractive index gradient which is due to said concentration gradients, wherein said refractive index gradient produces said focusing effect, and is substantially expressed, at least in the vicinity of said center axis in each planar cross section perpendicular to said center axis, by the following equation; n no (1 - ar2) wherein no represents the refractive index of the glass at said center axis, n represents the refractive index at a distance r from said center axis, and a is a positive constant at the planar cross section, said positive constant being such that the value thereof progressively increases from one surface toward the other surface of said entrance and exit surfaces for light, and wherein the diameter of said planar cross section perpendicular to said center axis decreases from said one surface toward said other surface of said entrance and exit surfaces for light.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |