← Back to Patent Explorer
US3753672A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for forming glass fibers

Assignee: HIRSCHOWITZ B
•
Filing: 1971-06-28
•
Granted: 1973-08-21
•
Expires: 1991-06-28
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method of forming an optical light transmitting glass coated glass fiber from a clear optical solid first glass body having a predetermined index of refraction and a second glass body surrounding the first glass body and having a lower index of refraction than the first body comprising: in one continuous step heating adjacent ends of the two glass bodies to a temperature, where the glass is sufficiently plastic to be drawn, and drawing glass from the heated ends while maintaining their temperature substantially constant to form a fiber comprising a continuous glass core of one predetermined index of refraction and a continuous glass coating of a lower index of refraction which is fused with the core in one solid mass and is adapted to prevent light from escaping from the core into the coating.

Inventors

  • 👤 L Curtiss

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 03:16
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/02; C; C03; C03B; C03B37/00; C03B37/01; C03B37/02; C03B37/025; C03B37/027; C03B37/029; C03C; C03C25/00; C03C25/10; C03C25/104; C03C25/106; C03C25/1061; C03B2205/00; C03B2205/12; C03B2205/16

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 154 words
A method of forming an optical light transmitting device having a core and a coating around it which acts as a light barrier to prevent the loss of light transmitted through the core, comprising the steps of feeding together in one direction and at a continuous speed an optically clear glass body having one index of refraction and a clear cladding glass around the body having a lower index of refraction, both glasses having the characteristic that they become plastic and begin to flow towards a point at temperatures within about 50 C of each other, circumferentially fusing the cladding glass to the body during this feeding at a temperature at which both glasses begin to plastically flow towards a point but do not run freely and immediately drawing the fused glasses off at a continuous high rate of speed relative to their feed rate to form a product of substantially reduced cross section.
Claim 2
Independent Claim 154 words
A method of forming an optical light transmitting device having a core and a coating around it which acts as a light barrier to prevent the loss of light transmitted through the core, comprising the steps of feeding together in one direction and at a continuous speed an optically clear glass body having one index of refraction and a clear cladding glass around the body having a lower index of refraction, both glasses having the characteristic that they become plastic and begin to flow towards a point at temperatures within about 50 C of each other, circumferentially fusing the cladding glass to the body during this feeding at a temperature at which both glasses begin to plastically flow towards a point but do not run freely and immediately drawing the fused glasses off at a continuous high rate of speed relative to their feed rate to form a product of substantially reduced cross section.
Claim 3
Independent Claim 163 words
A method of forming an optical light transmitting device having a core and a coating around it which acts as a light barrier to prevent the loss of light transmitted through the core, comprising the steps of feeding together in one direction at a continuous speed an optically clear glass body having an index of refraction on the order of about 1.6 to 1.8 and a clear cladding glass around the body having a lower index of refraction on the order of about 1.5, both glasses having the characteristic that they become plastic and begin to flow towards a point at temperatures within about 50* C of each other, circumferentially fusing the cladding glass to the body at a temperature at which both glasses begin to plastically flow towards a point but do not run freely and immediately drawing the fused glasses off at a high rate of speed relative to their feed rate to form a product of substantially reduced cross section.
Claim 4
Independent Claim 163 words
A method of forming an optical light transmitting device having a core and a coating around it which acts as a light barrier to prevent the loss of light transmitted through the core, comprising the steps of feeding together in one direction at a continuous speed an optically clear glass body having an index of refraction on the order of about 1.6 to 1.8 and a clear cladding glass around the body having a lower index of refraction on the order of about 1.5, both glasses having the characteristic that they become plastic and begin to flow towards a point at temperatures within about 50* C of each other, circumferentially fusing the cladding glass to the body at a temperature at which both glasses begin to plastically flow towards a point but do not run freely and immediately drawing the fused glasses off at a high rate of speed relative to their feed rate to form a product of substantially reduced cross section.
Claim 5
Dependent Claim 23 words
A method according to claim 2 wherein the fused glasses are drawn off at a tension of not more than about 40 grams.
Claim 6
Dependent Claim 21 words
A method according to claim 2 wherein the fused glasses are drawn off into a fine diameter fiber in one operation.
Claim 7
Dependent Claim 27 words
A method according to claim 2 wherein the cladding glass becomes plastic and begins to flow towards a point at a higher temperature than the glass body.
Claim 8
Dependent Claim 80 words
A method according to claim 5 wherein the glass body comprises a rod and the cladding glass a tube of optical glass of slightly larger diameter than the rod and the ends of these glasses are fused together into one solid mass by heating them to a temperature at which they become plastic and begin to flow towards a point and glass is then removed from the point and drawn down in one operation to form a fine diameter fiber.

References Cited (Backward Citations)

US1899146A Cited
US1793529A Cited
US1920366A Cited
US2313296A Cited
US2608722A Cited
US2825260A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-08-20 1977-02-19 1977-08-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-08-20 1981-02-19 1981-08-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-08-20 1985-02-19 1985-08-21 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag