Patent US3774991A successfully refreshed from Google Patents.
US3774991A
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Achromatic telephoto objective lens
Assignee: Nikon Corp
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Filing: 1971-12-20
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Granted: 1973-11-27
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Expires: 1991-12-20
Abstract
Abstract An achromatic objective lens comprises three to five components, of which at least two are positive and at least one is negative. At least one of the positive components is formed of fluophosphate crown glass or phosphate crown glass. At least one of the other positive components is formed of barium flint glass. At least one of the negative components is formed of lanthanum glass or antimony flint glass.
Inventors
- 👤 Y Shimizu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 11:59
CPC Classifications
G; G02; G02B; G02B9/00; G02B9/12; G02B13/00; G02B13/02
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
162 words
An achromatic objective lens as defined in claim 1, wherein said components have the following characteristics; Focal length f 300.0; Relative aperture F/4.5; Angle of field 8.4* r1 + 106.0 d1 11.0 nd 1.48606 Nu d 81.5 fluophosphoric acid glass r2 - 151.0 d2 4.0 r3 - 144.0 d3 3.0 nd 1.744 Nu d 44.9 lanthanum glass r4 + 130.0 d4 12.0 nd 1.6393 Nu d 45.0 barium flint glass r5 + 650.0 d5 1.0 r6 + 95.0 d6 7.7 nd 1.48606 Nu d 81.5 fluophosphoric acid glass r7 + 878.8 d7 119.3 r8 - 43.0 d8 1.0 nd 1.62041 Nu d 60.3 r9 + 150.0 d9 3.5 nd 1.62004 Nu d 36.3 r10 - 104.82 wherein r represents the radius of curvature of each component, d the center thickness or air gap of each component, nd the refractive index of each glass for Helium d-line of spectrum, and Nu d the Abbe''s number of each glass for Helium d-line of spectrum.
Claim 2
Dependent Claim
149 words
An achromatic objective lens as defined in claim 1, wherein said components have the following characteristics: focal length f 600.0; Relative aperture F/5.6 Angle of field 8*. r1 + 200.000 d1 15.0 nd 1.48606 Nu d 81.5 fluophosphoric acid glass r2 - 277.348 d2 6.0 r3 - 277.348 d3 6.0 nd 1.744 Nu d 44.9 lanthanum glass r4 + 387.299 d4 1.5 r5 + 224.820 d5 10.0 nd 1.56965 Nu d 49.5 barium flint glass r6 + 4430.700 d6 254.0 r7 - 93.000 d7 1.5 nd 1.52682 Nu d 51.1 r8 + 180.000 d8 6.0 nd 1.62374 Nu d 47.0 r9 - 148.925 wherein r represents the radius of curvature of each component, d the center thickness or air gap of each component, nd the refractive index of each glass for Helium d-line of spectrum, and Nu d the Abbe''s number of each glass for Helium d-line of spectrum.
Claim 3
Dependent Claim
149 words
An achromatic objective lens as defined in claim 1, wherein said components have the following characteristics: Focal length f 800.0; Relative aperture F/8; Angle of field 6* r1 + 300.0 d1 13.0 nd 1.48614 Nu d 81.5 fluophosphoric acid glass r2 - 430.0 d2 7.3 r3 - 382.5 d3 7.5 nd 1.61266 Nu d 44.3 antimony flint glass r4 + 310.0 d4 1.5 r5 + 292.0 d5 10.0 nd 1.56953 Nu d 49.5 barium flint glass r6 - 1654.4 d6 435.0 r7 - 150.0 d7 2.0 nd 1.51885 Nu d 59.0 r8 Infinity d8 5.0 nd 1.62399 Nu d 47.0 r9 - 233.27 wherein r represents the radius of curvature of each component, d the center thickness or air gap of each component, nd the refractive index of each glass for Helium d-line of spectrum, and Nu d the Abbe''s number of each glass for Helium d-line of spectrum.
Claim 4
Dependent Claim
146 words
An achromatic objective lens as defined in claim 1, wherein said components have the following characteristics: focal length f 1,200; Relative aperture F/11; Angle of field 4* r1 + 403.0 d1 13.0 nd 1.48606 Nu d 81.5 Fluophosphoric acid glass r2 - 413.0 d2 8.0 r3 - 428.0 d3 6.0 nd 1.744 Nu d 44.9 lanthanum glass r4 +1168.1 d4 2.0 r5 + 550.0 d5 10.0 nd 1.56965 Nu d 49.5 barium flint glass r6 -6230.7 d6 575.0 r7 - 190.0 d7 2.0 nd 1.5168 Nu d 64.2 r8 + 430.0 d8 7.0 nd 1.62374 Nu d 47.0 r9 -449.9 wherein r represents the radius of curvature of each component, d the center thickness or air gap of each component, nd the refractive index of each glass for Helium d-line of spectrum, and Nu d the Abbe''s number of each glass for Helium d-line of spectrum.
Claim 5
Dependent Claim
184 words
An achromatic objective lens as defined in claim 1, wherein said components have the following characteristics: Focal length f 1,200; Relative aperture F/11; Angle of field 4*. r1 + 310.0 d1 11.0 nd 1.61405 Nu d 55.1 bibarium flint glass r2 - 525.0 d2 5.0 r3 - 630.0 d3 7.5 nd 1.6115 Nu d 44.3 antimony flint glass r4 + 313.0 d4 4.0 r5 + 341.3 d5 10.0 nd 1.48606 Nu d 81.5 fluophosphoric acid glass r6 - 557.0 d6 7.0 r7 - 413.0 d7 7.5 nd 1.713 Nu d 53.9 lanthanum glass r8 + 814.0 d8 1.0 r9 + 700.0 d9 10.0 nd 1.62374 Nu d 47.0 barium flint glass r10 -2386.1 d10 533.0 r11 - 190.0 d11 2.0 nd 1.5168 Nu d 64.2 r12 + 310.0 d12 7.0 nd 1.62374 Nu d 47.0 r13 - 472.83 wherein r represents the radius of curvature of each component, d the center thickness or air gap of each components, nd the refractive index of each glass for Helium d-line of spectrum, and Nu d the Abbe''s number of each glass for Helium d-line of spectrum.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-26 | 1977-05-28 | 1977-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-26 | 1981-05-28 | 1981-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-26 | 1985-05-28 | 1985-11-27 | $7700.00 | Window Closed / Lapsed |