← Back to Patent Explorer
US4304467A Expired / Lapsed US ⏱️ 0.0 years remaining

Focussed laser beam optical system

Assignee: International Business Machines Corp
•
Filing: 1979-05-29
•
Granted: 1981-12-08
•
Expires: 1999-05-29
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The focal range of a focussed laser beam is enlarged with a simple optical stop where the beam has a Gaussian cross-sectional profile. The stop is arranged between the laser producing the beam, and a beam focussing lens system, and it is provided with an aperture of predetermined diameter with respect to that of the laser beam whereby the outer portion of the beam represented by the low intensity skirts of the profile curve is stopped. This arrangement can influence the focal range up to a 75 percent increase over that obtained with the unstopped beam.

Inventors

  • 👤 Melbourne E. Rabedeau

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 16:11
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/09; G02B27/0927; G02B27/0938; G02B27/0988; G02B5/00; G02B5/005; G06; G06K; G06K7/00; G06K7/10; G06K7/10544; G06K7/10821; G06K7/10831; G06K2207/00; G06K2207/1013

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 99 words
A focussed laser beam optical system providing increased focal range, comprising a laser for generating a beam of coherent light having a given diameter and a guassian profile diametrically, a focussing lens system aligned with said laser for bringing the light in said beam of light to a focus, and an optical stop aligned with said lens system and having an aperture of diameter at which the density of said beam of light is 0.08 to 0.20 of the peak intensity of said beam of light, whereby the focal range is substantially greater than for the original focussed beam.
Claim 2
Dependent Claim 99 words
A focussed laser beam optical system providing increased focal range, comprising a laser for generating a beam of coherent light having a given diameter and a guassian profile diametrically, a focussing lens system aligned with said laser for bringing the light in said beam of light to a focus, and an optical stop aligned with said lens system and having an aperture of diameter at which the density of said beam of light is 0.08 to 0.20 of the peak intensity of said beam of light, whereby the focal range is substantially greater than for the original focussed beam.
Claim 3
Dependent Claim 98 words
A focussed laser beam optical system providing increased focal range, comprising a laser for generating a beam of coherent light having a given diameter and a gaussian profile diametrically, a focussing lens system aligned with said laser for bringing the light in said beam to a focus, and an optical stop aligned with said laser and said lens system and having an aperture of diameter at which the intensity of said beam of light is 0.20 of the peak intensity of said beam of light, whereby the focal range is substantially greater than for the original focussed beam.
Claim 4
Dependent Claim 98 words
A focussed laser beam optical system providing increased focal range, comprising a laser for generating a beam of coherent light having a given diameter and a gaussian profile diametrically, a focussing lens system aligned with said laser for bringing the light in said beam to a focus, and an optical stop aligned with said laser and said lens system and having an aperture of diameter at which the intensity of said beam of light is 0.20 of the peak intensity of said beam of light, whereby the focal range is substantially greater than for the original focussed beam.
Claim 5
Dependent Claim 98 words
A focussed laser beam optical system providing increased focal range, comprising a laser for generating a beam of coherent light having a given diameter and a gaussian profile diametrically, a focussing lens system aligned with said laser for bringing the light in said beam to a focus, and an optical stop aligned with said laser and said lens system and having an aperture of diameter at which the intensity of said beam of light is 0.135 of the peak intensity of said beam of light. whereby the focal range is substantially greater than for the original focussed beam.
Claim 6
Dependent Claim 98 words
A focussed laser beam optical system providing increased focal range, comprising a laser for generating a beam of coherent light having a given diameter and a gaussian profile diametrically, a focussing lens system aligned with said laser for bringing the light in said beam to a focus, and an optical stop aligned with said laser and said lens system and having an aperture of diameter at which the intensity of said beam of light is 0.135 of the peak intensity of said beam of light. whereby the focal range is substantially greater than for the original focussed beam.
Claim 7
Dependent Claim 28 words
A focussed laser beam optical system as defined in claim 3, and incorporating an optical beam expanding system interposed between said laser generating apparatus and said optical stop.

References Cited (Backward Citations)

FR2040507A5 Cited
US3787107A Cited
US3750189A Cited
US3801182A Cited
US3980397A Cited
US4030817A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-12-07 1985-06-08 1985-12-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-12-07 1989-06-08 1989-12-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-12-07 1993-06-08 1993-12-08 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag