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Method of manufacturing gradient index optical elements

Assignee: Olympus Corp
•
Filing: 1992-02-18
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Granted: 1993-08-24
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Expires: 2012-02-18
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Abstract

Abstract A method of manufacturing gradient index optical element comprises preparing a sol using silicon alkoxide and a metal alkoxide as a dopant source of index-modifying cations. The sol is treated to obtain a wet gel. Metal alkoxide from the wet gel is eluted by immersing the wet gel in a solvent to produce a concentration gradiation of the metal alkoxide in the wet gel, and the wet gel is then washed. The steps of eluting and washing are repeated so that a gradient index optical element is produced having a large difference in refractive index between the outer periphery portion and the center of the gel.

Inventors

  • 👤 Minoru Inami
  • 👤 Satoshi Noda

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 21:20
CPC Classifications
C; C03; C03C; C03C1/00; C03C1/006

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 107 words
A method of manufacturing a gradient index optical element utilizing a sol-gel process, comprising the steps of: (a) preparing a sol by adding a metal alkoxide as a source of refractive index-modifying dopant to silicon alkoxide; (b) subjecting said sol to a gelling treatment to obtain a wet gel; (c) immersing said wet gel in a solvent to elute some of said dopant from said gel to produce a concentration gradient of said dopant in said gel, and thereafter washing said gel; (d) repeating the above sep (c) at least once; and (e) drying said wet gel to obtain a dry gel and sintering said dry gel.
Claim 2
Independent Claim 107 words
A method of manufacturing a gradient index optical element utilizing a sol-gel process, comprising the steps of: (a) preparing a sol by adding a metal alkoxide as a source of refractive index-modifying dopant to silicon alkoxide; (b) subjecting said sol to a gelling treatment to obtain a wet gel; (c) immersing said wet gel in a solvent to elute some of said dopant from said gel to produce a concentration gradient of said dopant in said gel, and thereafter washing said gel; (d) repeating the above sep (c) at least once; and (e) drying said wet gel to obtain a dry gel and sintering said dry gel.
Claim 3
Dependent Claim 46 words
A method of manufacturing a gradient index optical element according to claim 1; wherein the duration of the immersing of the wet gel carried out in step (c) is greater than the duration in each repeated immersing of the wet gel carried out in step (d).
Claim 4
Dependent Claim 40 words
A method of manufacturing a gradient index optical element according to claim 1; wherein the immersing of the wet gel in step (c) is carried out for a duration sufficient to allow the solvent to reach the center of the
Claim 5
Dependent Claim 42 words
A method of manufacturing a gradient index optical element according to claim 1; wherein each repeated immersing of the wet gel in step (d) is carried out for a duration insufficient to allow the solvent to reach the center of the gel.
Claim 6
Dependent Claim 20 words
A method of manufacturing a gradient index optical element according to claim 1; wherein the silicon alkoxide is silicon tetramethoxide.
Claim 7
Dependent Claim 20 words
A method of manufacturing a gradient index optical element according to claim 5; wherein the metal alkoxide is titanium tetra-n-buthoxide.
Claim 8
Dependent Claim 20 words
A method of manufacturing a gradient index optical element according to claim 1; wherein the metal alkoxide is titanium tetra-n-buthoxide.
Claim 9
Dependent Claim 20 words
A method of manufacturing a gradient index optical element according to claim 1; wherein the repeating step is performed twice.
Claim 10
Dependent Claim 21 words
A method of manufacturing a gradient index optical element according to claim 1; wherein the repeating step is performed three times.

References Cited (Backward Citations)

US4686195A Cited
US4797376A Cited
US4902650A Cited
US5069700A Cited
US5068208A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-08-23 1997-02-22 1997-08-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-08-23 2001-02-22 2001-08-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-08-23 2005-02-22 2005-08-24 $7700.00 Window Closed / Lapsed

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