US3853564A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Graphic aid and methods related thereto
Assignee: Fotel Inc
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Filing: 1972-03-01
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Granted: 1974-12-10
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Expires: 1992-03-01
Abstract
Abstract A master grid layout sheet and methods of manufacture associated therewith are disclosed for use in graphic art work such as the layout and reproduction of printed circuits and the like. In typical printed circuit work precision art work and subsequent photographic reproduction thereof are normal intermediate processing steps. The master sheet includes a pattern, usually of orthogonal reference lines, printed thereon in a predetermined critical gray or neutral monotone. The monotone has a visual density such that the reference line pattern is visible to a draftsman but the light transmission density or opacity thereof is insufficient to cause the pattern to be reproduced in a controlled photographic reproduction of the master sheet.
Inventors
- 👤 E Baker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 00:14
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/0002; H05K2201/00; H05K2201/09; H05K2201/09818; H05K2201/09936; H05K2203/00; H05K2203/05; H05K2203/0548; H05K2203/056
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
156 words
A METHOD OF PRODUCING MASTER GRID LAYOUT SHEETS ON A LIGHT SENSITIVE MATERIAL HAVING A KNOWN GAMMA UP TO A PREDETERMINED LIGHT SATURATION LEVEL, SAID SHEETS INCLUDING A PATTERN OF GRAY MONOTONE EFFECTS COMPRISING THE STEPS OF A. EXPOSING SAID LIGHT SENSITIVE MATERIAL THROUGH A DESIRED PATTERN TO REPRESENT SAID PATTERN OF GRAY MONOTONE EFFECTS, SAID MATERIAL BEING EXPOSED TO LIGHT SUCH THAT SAID PATTERN IS SUBSTANTIALLY UNIFORMLY EXPOSED TO AN AMOUNT OF LIGHT SUBSTANTIALLY LESS THAN SAID SATURATION LEVEL, B. PLACING SAID LIGHT SENSITIVE MATERIAL IN A DEVELOPING FLUID TO DEVELOP SAID EXPOSED AREAS, C. TERMINATING SAID DEVELOPING STEP WHEN SAID GRAY MONOTONE AREAS HAVE A PREDETERMINED OPTICAL DENSITY, D. FIXING SAID SENSITIVE MATERIAL TO PREVENT ANY FURTHER DEVELOPMENT THEREOF, AND E. SAID PREDETERMINED OPTICAL DENSITY BEING SUFFICIENT TO BE VISIBLE IN THE SHEET BUT HAVING A SUFFICIENTLY LOW OPTICAL DENSITY THAT SAID PATTERN WILL NOT BE PRESENT WHEN SAID SHEET IS SUBSEQUENTLY PHOTOGRAPHICALLY REPRODUCED.
Claim 2
Independent Claim
156 words
A METHOD OF PRODUCING MASTER GRID LAYOUT SHEETS ON A LIGHT SENSITIVE MATERIAL HAVING A KNOWN GAMMA UP TO A PREDETERMINED LIGHT SATURATION LEVEL, SAID SHEETS INCLUDING A PATTERN OF GRAY MONOTONE EFFECTS COMPRISING THE STEPS OF A. EXPOSING SAID LIGHT SENSITIVE MATERIAL THROUGH A DESIRED PATTERN TO REPRESENT SAID PATTERN OF GRAY MONOTONE EFFECTS, SAID MATERIAL BEING EXPOSED TO LIGHT SUCH THAT SAID PATTERN IS SUBSTANTIALLY UNIFORMLY EXPOSED TO AN AMOUNT OF LIGHT SUBSTANTIALLY LESS THAN SAID SATURATION LEVEL, B. PLACING SAID LIGHT SENSITIVE MATERIAL IN A DEVELOPING FLUID TO DEVELOP SAID EXPOSED AREAS, C. TERMINATING SAID DEVELOPING STEP WHEN SAID GRAY MONOTONE AREAS HAVE A PREDETERMINED OPTICAL DENSITY, D. FIXING SAID SENSITIVE MATERIAL TO PREVENT ANY FURTHER DEVELOPMENT THEREOF, AND E. SAID PREDETERMINED OPTICAL DENSITY BEING SUFFICIENT TO BE VISIBLE IN THE SHEET BUT HAVING A SUFFICIENTLY LOW OPTICAL DENSITY THAT SAID PATTERN WILL NOT BE PRESENT WHEN SAID SHEET IS SUBSEQUENTLY PHOTOGRAPHICALLY REPRODUCED.
Claim 3
Dependent Claim
28 words
The method of claim 1 wherein the pattern is visually monitored during the development step to terminate said development step when said pattern attains said predetermined optical density.
Claim 4
Dependent Claim
81 words
The method of claim 2 wherein said material is further exposed to a visual process control guide comprising an auxiliary pattern of small unexposed areas and adjacent areas exposed to saturation to form a half-tone which develops to a final effective visual density bearing a predetermined known relationship to said predetermined optical density more quickly than said monotone pattern will so develop, and comparing said optical density to said effective visual density to terminate said development step at the optimum time.
Claim 5
Dependent Claim
77 words
The method of claim 3 wherein the visual process control guide includes a plurality of comparator test patches, including a first patch having visual density appearing equal to the predetermined optical visual density of said monotone pattern, a second patch having a visual density greater than said predetermined optical density, and a third patch having visual density less than said predetermined optical density, said second and third patches establishing upper and lower limits for the monotone pattern.
Claim 6
Dependent Claim
42 words
The method of claim 14 including the steps of placing an effectively opaque pattern on said material following said development step, and photographically reproducing the pattern on said material whereby only said effectively opaque pattern will be present in the photographic reproductions.
Claim 7
Dependent Claim
111 words
The method of claim 1 wherein said desired pattern is on a first area of a master negative and an appropriate pattern to produce an effectively opaque pattern is, on a second area of said negative, including the steps of f. exposing said light sensitive material through said master negative to a first light source, g. placing a mask over a portion of said light sensitive material exposed to said desired pattern, and h. exposing said material to a second light source, the duration and intensity of said light source in each of said exposing steps being related whereby said monotone and effectively opaque patterns are reproduced respectively on said material.
Claim 8
Dependent Claim
50 words
The method of claim 6 wherein the ratio of the intensity of said second light source to the intensity of said first light source is about ten to one and the exposure interval for said first light is substantially the same as the exposure interval for said second light source.
Claim 9
Dependent Claim
36 words
The method of claim 4 wherein said optical density of said monotone pattern is critically fixed within a range of about 0.25 to about 0.35 above the density of unexposed sensitive material after said fixing step.
Claim 10
Dependent Claim
36 words
The method of claim 14 wherein said optical density of said monotone pattern is critically fixed within a range of about 0.2 to about 0.4 above the density of unexposed sensitive material after said fixing step.
Claim 11
Dependent Claim
89 words
The method of claim 1 wherein said monotone pattern and an effectively opaque pattern are introduced on a negative for exposing said material and the relative exposures of said monotone pattern and said effectively opaque pattern are controlled, whereby the ratio of the density on said material after said fixing step of said monotone pattern to the density of said material underlying said effectively opaque pattern is ten to one and the portion of said material not underlying either of said patterns is exposed to about the saturation level.
Claim 12
Dependent Claim
102 words
The method of claim 1 wherein said desired pattern is on a first area of a master negative and an appropriate pattern is on a second area of said negative to produce an effectively opaque pattern on the master grid layout sheet, said method including the steps of placing a light controlling mask over said first area, and controlling the exposing step of said method whereby the duration and intensity of said exposure of said light sensitive material is controlled whereby said monotone pattern is produced thereon in said first area and said effectively opaque pattern is produced in said second area.
Claim 13
Dependent Claim
31 words
The method of claim 11 wherein the ratio of total incident light exposure of said first area to the total incident light exposure of said second area is one to ten.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-09 | 1978-06-10 | 1978-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-09 | 1982-06-10 | 1982-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-09 | 1986-06-10 | 1986-12-10 | $7700.00 | Window Closed / Lapsed |