US4455893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method in producing a mould for a lens
Assignee: OPTIK INNOVATION OIAB A Co OF SWEDEN AB
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Filing: 1981-10-28
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Granted: 1984-06-26
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Expires: 2001-10-28
Abstract
Abstract In a method for producing a lens, particularly a glass lens or a mould for casting a lens, particularly a plastics lens, a lens or mould blank (3) is given rotation about an axis of symmetry to the blank relative a material-removing tool (7) and the tool (7) is applied to the surface (4) of the blank (3). A laser unit (7) is utilized as a tool, and the beam (11) of the laser unit (7) is caused with its focus (12) to provide vaporization and/or fusion of the surface material (4) on the blank (3) which is to be removed.
Inventors
- 👤 Ulf J. Astero
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:39
CPC Classifications
B; B29; B29D; B29D11/00; B29D11/00932; B23; B23K; B23K26/00; B23K26/08; B23K26/0823
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
118 words
A method for production of a metal mould for moulding a rotational symmetric lens, comprising mechanically removing material from the surface of a mould metal blank to form a rotational symmetric blank surface having substantially the desired surface shape, and reducing the mould surface irregularities resulting from the material removing operation in order to form an optically smooth mould surface characterized thereby that said reducing comprises rotating the surface shaped blank about the axis of symmetry, directing a laser beam in parallel with said axis onto said blank surface, displacing the laser beam radially relative to said surface and bringing the laser beam to melt the top layer of the mould surface thereby to smooth out said irregularities.
Claim 2
Independent Claim
118 words
A method for production of a metal mould for moulding a rotational symmetric lens, comprising mechanically removing material from the surface of a mould metal blank to form a rotational symmetric blank surface having substantially the desired surface shape, and reducing the mould surface irregularities resulting from the material removing operation in order to form an optically smooth mould surface characterized thereby that said reducing comprises rotating the surface shaped blank about the axis of symmetry, directing a laser beam in parallel with said axis onto said blank surface, displacing the laser beam radially relative to said surface and bringing the laser beam to melt the top layer of the mould surface thereby to smooth out said irregularities.
Claim 3
Dependent Claim
33 words
A method as claimed in claim 1, characterized in that at least the surface portions of the blank are kept at heightened temperature while it is subjected to the action of the laser.
Claim 4
Dependent Claim
26 words
A method as claimed in claim 1 or 2, characterized in that the laser is caused to machine the blank surface in mutually consecutive annular areas.
Claim 5
Dependent Claim
26 words
A method as claimed in claim 3, characterized in that the cutting point of the laser is displaced in the direction of the axis by refocusing.
Claim 6
Dependent Claim
34 words
A method as claimed in claim 1 or 2, characterized in that the cutting point of the laser is displaced in the direction of the axis by displacing the laser unit in said direction.
Claim 7
Dependent Claim
32 words
A method as claimed in claim 3, characterized in that the cutting point of the laser is displaced in the direction of the axis by displacing the laser unit in said direction.
Claim 8
Dependent Claim
32 words
A method as claimed in claim 4, characterized in that the cutting point of the laser is displaced in the direction of the axis by displacing the laser unit is said direction.
Claim 9
Dependent Claim
20 words
A method as claimed in claim 3, characterized in that the laser is radially displaced stepwise to consecutive annular areas.
References Cited (Backward Citations)
DE2804479A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-06-26 | 1987-12-26 | 1988-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-06-26 | 1991-12-26 | 1992-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-06-26 | 1995-12-26 | 1996-06-26 | $7700.00 | Window Closed / Lapsed |