Patent US4653398A successfully refreshed from Google Patents.
Patent US4751530A successfully refreshed from Google Patents.
US4751530A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acoustic lens arrays for ink printing
Assignee: Xerox Corp
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Filing: 1986-12-19
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Granted: 1988-06-14
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Expires: 2006-12-19
Abstract
Abstract To facilitate the fabrication of acoustic printheads, arrays of spherical acoustic lenses are provided for bringing rf acoustic waves to essentially diffraction limited focii at or near the free surface of a pool of ink. These lenses produce focal patterns which are relatively free of localized amplitude variations, so they may be employed to fabricate acoustic printheads having relatively stable characteristics for acoustic printing.
Inventors
- 👤 Scott A. Elrod
- 👤 Butrus T. Khuri-Yakub
- 👤 Calvin F. Quate
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:56
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/135; B41J2/14; B41J2/14008; B41J2/145; B41J2/155; B41J2002/14322
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
145 words
An acoustic printhead for ejecting droplets of ink on demand from a free surface of a pool of liquid ink, said ink having a predetermined acoustic velocity; said printhead comprising a solid substrate having an upper surface with a plurality of essentially identical, generally spherically shaped indentations formed therein on predetermined centers to define an array of acoustic lenses, and a lower surface; said substrate being composed of a material having an acoustic velocity which is substantially higher than the acoustic velocity of said ink; and piezoelectric transducer means intimately coupled to the lower surface of said substrate for generating rf acoustic waves to illuminate said lenses, such that said lenses launch respective converging acoustic beams into said ink, with the focal lengths of said lenses being selected to cause said beams to come to focus on spaced apart centers approximately at said free surface.
Claim 2
Dependent Claim
145 words
An acoustic printhead for ejecting droplets of ink on demand from a free surface of a pool of liquid ink, said ink having a predetermined acoustic velocity; said printhead comprising a solid substrate having an upper surface with a plurality of essentially identical, generally spherically shaped indentations formed therein on predetermined centers to define an array of acoustic lenses, and a lower surface; said substrate being composed of a material having an acoustic velocity which is substantially higher than the acoustic velocity of said ink; and piezoelectric transducer means intimately coupled to the lower surface of said substrate for generating rf acoustic waves to illuminate said lenses, such that said lenses launch respective converging acoustic beams into said ink, with the focal lengths of said lenses being selected to cause said beams to come to focus on spaced apart centers approximately at said free surface.
Claim 3
Dependent Claim
21 words
The printhead of claim 1 wherein said acoustic lenses are aligned to define a page width long linear array of lenses.
Claim 4
Dependent Claim
23 words
The printhead of claim 1 wherein said acoustic lenses are aligned to define a page width long two dimensional array of staggered lenses.
Claim 5
Dependent Claim
18 words
The printhead of claim 1 wherein said acoustic lenses are aligned to define a linear array of lenses.
Claim 6
Dependent Claim
20 words
The printhead of claim 1 wherein said said acoustic lenses are aligned to define a two dimensional array of lenses.
Claim 7
Dependent Claim
52 words
The printhead of any one of claim 1-5 wherein said transducer means supplies independently modulated rf acoustic waves for individually illuminating said lenses, whereby said lenses launch separately modulated acoustic beams into said ink, with the modulation of said acoustic beams being controlled on a lens-by-lens basis for drop on demand printing.
Claim 8
Dependent Claim
27 words
The printhead of claim 6 wherein said substrate has acoustic impedance mismatch regions which are disposed between said lenses for acoustically isolating said lenses from each other.
Claim 9
Dependent Claim
19 words
The printhead of claim 7 wherein said impedance mismatch regions extend upward into said substrate from its lower surface.
Claim 10
Dependent Claim
19 words
The printhead of claim 7 wherein said impedance mismatch regions extend downward into said substrate from its upper surface.
Claim 11
Dependent Claim
27 words
The printhead of claim 1 wherein the velocity of sound in said substrate is at least 2.5 times higher than the velocity of sound in said ink.
Claim 12
Dependent Claim
27 words
The printhead of claim 10 wherein the velocity of sound in said substrate is at least four times higher than the velocity of sound in said ink.
Claim 13
Dependent Claim
36 words
The printhead of claim 1 wherein said indentations are filled with a solid material having an acoustic velocity comparable to that of said ink, whereby said printhead presents a generally planar upper surface to said ink.
Claim 14
Dependent Claim
27 words
The printhead of claim 12 wherein the velocity of sound in said substrate is at least 2.5 times higher than the velocity of sound in said ink.
Claim 15
Dependent Claim
27 words
The printhead of claim 12 wherein the velocity of sound in said substrate is at least four times higher than the velocity of sound in said ink.
Claim 16
Dependent Claim
32 words
The printhead of claim 1 wherein said acoustic waves have a predetermined wavelength in said substrate, and said acoustic lenses have a predetermined diameter which is less than ten times said wavelength.
Claim 17
Dependent Claim
27 words
The printhead of claim 15 wherein the velocity of sound in said substrate is at least 2.5 times higher than the velocity of sound in said ink.
Claim 18
Dependent Claim
27 words
The printhead of claim 16 wherein the velocity of sound in said substrate is at least four times higher than the velocity of sound in said ink.
Claim 19
Dependent Claim
51 words
The printhead of any of claim 17 wherein said transducer means supplies independently modulated rf acoustic waves for individually illuminating said lenses, whereby said lenses launch separately modulated acoustic beams into said ink, with the modulation of said acoustic beams being controlled on a len-by-lens basis for drop on demand printing.
Claim 20
Dependent Claim
41 words
The printhead of claim 18 wherein said indentations are filled with a solid material having an acoustic velocity comparable to that of the ink, whereby said acoustic beams are launched into said ink from a generally planar surface of said printhead.
Claim 21
Dependent Claim
22 words
The printhead of any one of claims 1 and 7-19 wherein said substrate and said transducer means are submerged in said ink,
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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) | 1991-06-14 | 1991-12-14 | 1992-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-14 | 1995-12-14 | 1996-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-14 | 1999-12-14 | 2000-06-14 | $7700.00 | Window Closed / Lapsed |