Patent US3761677A successfully refreshed from Google Patents.
US3761677A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for producing single crystals including halogen lamps aligned with the common major axes of a spheroidal reflector pair
Assignee: NEC Corp
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Filing: 1972-02-02
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Granted: 1973-09-25
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Expires: 1992-02-02
Abstract
Abstract For an apparatus for growing single crystals by the floating zone method, a pair of congruent prolate spheroidal reflectors for radiant energy are disposed outwardly of each other with their major axes aligned and with the distance between their axially inwardly disposed foci being less than the diameter of a molten zone placed at the location of these foci. A pair of congruent halogen lamps for supplying the radiant energy are held inside the respective spheroidal surfaces with their logitudinal axes parallel to the major axes and with the center of each lamp placed, apart from the axially outwardly disposed focus, less than a quarter of the longitudinal dimension of the lamps and a half of the transverse dimension thereof in the directions parallel and perpendicular to the major axes, respectively.
Inventors
- 👤 T Mizutani
- 👤 T Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:21
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/0014; C; C30; C30B; C30B13/00; C30B13/16; C30B13/22; C30B13/24; H05B3/0033; H05B3/0038; Y; Y10; Y10S; Y10S117/00; Y10S117/90; Y10T; Y10T117/00; Y10T117/10; Y10T117/1024; Y10T117/1076; Y10T117/1088
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
228 words
An apparatus for growing single crystals with radiant energy supplied from a pair of elongated halogen lamps and concentrated by cooperation of a pair of inwardly reflecting, substantially prolate spheroidal surface portions disposed outwardly of each other having their major axes substantially aligned with each other, wherein the improvement comprises: means for holding said spheroidal surface portions in such a manner that the distance between the axially inwardly disposed foci of said spheroidal surfaces is less than the dimension of said molten zone in the direction of said aligned major axes; means for holding said lamps inside said spheroidal surfaces, respectively, in such a manner that the longitudinal axes of said lamps are substantially parallel to said aligned major axes, and that the center of each said lamp is spaced from the axially outwardly disposed focus of the associated surfaces by less than one quarter of the longitudinal dimension of the lamp when measured in an inward or outward direction parallel to the aligned major axes and less than one-half of the transverse dimension of the lamp when measured along a plane perpendicular to said aligned major axes from said aligned major axes; and means for holding said molten zone in a position such that said radiant energy converging toward at least one of said axially inwardly disposed foci is incident on the surface of said molten zone.
Claim 2
Independent Claim
228 words
An apparatus for growing single crystals with radiant energy supplied from a pair of elongated halogen lamps and concentrated by cooperation of a pair of inwardly reflecting, substantially prolate spheroidal surface portions disposed outwardly of each other having their major axes substantially aligned with each other, wherein the improvement comprises: means for holding said spheroidal surface portions in such a manner that the distance between the axially inwardly disposed foci of said spheroidal surfaces is less than the dimension of said molten zone in the direction of said aligned major axes; means for holding said lamps inside said spheroidal surfaces, respectively, in such a manner that the longitudinal axes of said lamps are substantially parallel to said aligned major axes, and that the center of each said lamp is spaced from the axially outwardly disposed focus of the associated surfaces by less than one quarter of the longitudinal dimension of the lamp when measured in an inward or outward direction parallel to the aligned major axes and less than one-half of the transverse dimension of the lamp when measured along a plane perpendicular to said aligned major axes from said aligned major axes; and means for holding said molten zone in a position such that said radiant energy converging toward at least one of said axially inwardly disposed foci is incident on the surface of said molten zone.
Claim 3
Dependent Claim
58 words
The apparatus as claimed in claim 1, further comprising: a tube of a refractory material that is translucent with respect to said radiant energy for accommodating said molten zone and for substantially defining a chamber together with said spheroidal surface portions, said tube being disposed perpendicular to said aligned major axes; and means for forcibly ventilating said chamber.
Claim 4
Dependent Claim
19 words
The apparatus as claimed in claim 2, wherein said ventilating means comprises means for introducing gas into said chamber.
Claim 5
Dependent Claim
20 words
The apparatus as claimed in claim 2, wherein said ventilating means comprises means for sucking gas out of said chamber.
Claim 6
Dependent Claim
21 words
The apparatus as claimed in claim 1, wherein said spheroidal surface portions are substantially congruent and said lamps are substantially congruent.
Claim 7
Dependent Claim
16 words
The apparatus as claimed in claim 5, wherein said spheroidal surface portions have coMmon mating ends.
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) | 1976-09-24 | 1977-03-26 | 1977-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-24 | 1981-03-26 | 1981-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-24 | 1985-03-26 | 1985-09-25 | $7700.00 | Window Closed / Lapsed |