§
PatentCue
Patent Intelligence
Join Waitlist Sign In
← Back to Patent Explorer
US5069700A Expired / Lapsed US ⏱️ 0.0 years remaining

method of manufacturing gradient-index glass

Assignee: Tokyo Institute of Technology
•
Filing: 1991-03-11
•
Granted: 1991-12-03
•
Expires: 2011-03-11
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method of manufacturing a large-diameter gradient-index glass having a predetermined refractive index gradient includes the steps of (a) hydrolyzing a solution consisting of an alkoxide of silicon and an alkoxide of boron to prepare a sol, (b) adding an aqueous solution of lead acetate and an organic acid to the sol to prepare a gel porous body, (c) aging and sequentially treating the gel porous body by using a water-isopropanol solution of lead acetate, an isopropanol-acetone solution, and acentone, thereby performing a pretreatment, (d) dipping the pretreated gel porous body into a lower alcohol solution of at least one of potassium acetate and sodium acetate to form a lead ion concentration distribution which is gradually changed from a surface to an interior of the gel porous body, (e) sequentially treating the gel porous body having the lead ion concentration distribution by sequentially using an isopropanol-acetone solution and acentone, and (f) drying and heating the gel porous body to prepare a glass body.

Inventors

  • 👤 Masayuki Yamane
  • 👤 Atsuo Yasumori

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 07:11
CPC Classifications
C; C03; C03B; C03B19/00; C03B19/12; C03C; C03C1/00; C03C1/006; C03C3/00; C03C3/04; C03C3/076; C03C3/102; C03C3/108

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 157 words
A method of manufacturing a gradient-index glass, comprising the steps of: (a) hydrolyzing a solution consisting of an alkoxide of silicon and an alkoxide of boron to prepare a sol; (b) adding an aqueous solution of lead acetate and an organic acid to said sol to prepare a gel porous body; (c) aging and sequentially treating said gel porous body by sequentially using a water-isopropanol solution of lead acetate, an isopropanol-acetone solution, and acentone, thereby performing a pretreatment; (d) dipping said pretreated gel porous body into a lower alcohol solution of at least one of potassium acetate and sodium acetate to form a lead ion concentration distribution which is gradually changed from a surface to an interior of said gel porous body; (e) sequentially treating said gel porous body having the lead ion concentration distribution by sequentially using an isopropanol-acetone solution and acentone; and (f) drying and heating said gel porous body to prepare a glass body.
Claim 2
Independent Claim 157 words
A method of manufacturing a gradient-index glass, comprising the steps of: (a) hydrolyzing a solution consisting of an alkoxide of silicon and an alkoxide of boron to prepare a sol; (b) adding an aqueous solution of lead acetate and an organic acid to said sol to prepare a gel porous body; (c) aging and sequentially treating said gel porous body by sequentially using a water-isopropanol solution of lead acetate, an isopropanol-acetone solution, and acentone, thereby performing a pretreatment; (d) dipping said pretreated gel porous body into a lower alcohol solution of at least one of potassium acetate and sodium acetate to form a lead ion concentration distribution which is gradually changed from a surface to an interior of said gel porous body; (e) sequentially treating said gel porous body having the lead ion concentration distribution by sequentially using an isopropanol-acetone solution and acentone; and (f) drying and heating said gel porous body to prepare a glass body.
Claim 3
Dependent Claim 13 words
A method according to claim 1, wherein said alkoxide of silicon is tetramethoxysilane.
Claim 4
Dependent Claim 14 words
A method according to claim 1, wherein said alkoxide of boron is boron ethoxide.
Claim 5
Dependent Claim 13 words
A method according to claim 1, wherein said organic acid is acetic acid.
Claim 6
Dependent Claim 20 words
A method according to claim 1, wherein a concentration of water in said water-isopropanol solution is not more than 20%.
Claim 7
Dependent Claim 12 words
A method according to claim 1, wherein said lower alcohol is ethanol.
Claim 8
Dependent Claim 47 words
A method according to claim 1, wherein said drying step (f) is performed such that said gel porous body is placed in a vessel saturated with acetone vapor and is dried while acetone is gradually evaporated through small holes formed in a cover member of said vessel.

References Cited (Backward Citations)

US4422965A Cited
US4397666A Cited
US4419115A Cited
US4681615A Cited
US4441905A Cited
US4454237A Cited
US4680046A Cited
US4937208A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-12-02 1995-06-03 1995-12-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-12-02 1999-06-03 1999-12-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-12-02 2003-06-03 2003-12-03 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag