Patent US3451745A successfully refreshed from Google Patents.
US3451745A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Large aperture seven-lens objective lens system
Assignee: Pentax Corp
•
Filing: 1966-02-28
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Granted: 1969-06-24
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Expires: 1986-02-28
Abstract
No abstract record available.
Inventors
- 👤 Tomokazu Kazamaki
- 👤 Yasuo Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:01
CPC Classifications
G; G02; G02B; G02B13/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
15 words
75$N1, N2, N5, N6, N7,$1.85 1.65$N3$1.75 1.58$N4$1.75 F1,2$F/1.55 F1,2,3$F/0.32 F1,2,3,4,5$F/0.35 F/0.65$F1,2,3,4,5,6$F/0.5 0.98$N4/N5$0.85 0.4F$R6$0.3F 0.8F$R8$3.5F 0.85F$L$1.2F
Claim 2
Dependent Claim
15 words
75$N1, N2, N5, N6, N7,$1.85 1.65$N3$1.75 1.58$N4$1.75 F1,2$F/1.55 F1,2,3$F/0.32 F1,2,3,4,5$F/0.35 F/0.65$F1,2,3,4,5,6$F/0.5 0.98$N4/N5$0.85 0.4F$R6$0.3F 0.8F$R8$3.5F 0.85F$L$1.2F
References Cited (Backward Citations)
US3012476A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-06-23 | 1972-12-23 | 1973-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-06-23 | 1976-12-23 | 1977-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-06-23 | 1980-12-23 | 1981-06-24 | $7700.00 | Window Closed / Lapsed |