US5903380A
Expired / Lapsed
US
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Micro-electromechanical (MEM) optical resonator and method
Assignee: Teledyne Scientific and Imaging LLC
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Filing: 1997-05-01
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Granted: 1999-05-11
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Expires: 2017-05-01
Abstract
Abstract An integrated micro-electromechanical (MEM) optical resonator comprises a cantilever beam which is fixed to a substrate at one end and extends freely over the substrate at the other end, and a bimorph actuator stacked atop the beam at its fixed end. A reflective surface partially covers the top of the beam at its free end. The bimorph actuator comprises material layers having different thermal expansion coefficients. A DC-biased AC voltage connected across the actuator causes it to heat and cool as the current passing through it increases and decreases, creating a thermal bimorph effect which causes the cantilever beam and the reflective surface to oscillate in accordance with the varying current, preferably at the beam and actuator structure's fundamental resonant frequency. Combining the resonator with a light source and actuator excitation circuitry creates an optical scanner engine which delivers a scan angle in excess of 20 degrees and a scan rate of up to 2000 Hz, using a driving voltage of only 2 V p-p .
Inventors
- 👤 M. Edward Motamedi
- 👤 Angus P. Andrews
- 👤 Sangtae Park
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 01:56
CPC Classifications
G; G02; G02B; G02B26/00; G02B26/08; G02B26/0816; G02B26/0833; G02B26/0866; B; B81; B81B; B81B3/00; B81B3/0035; G02B26/10; G02B26/101; G06; G06K; G06K7/00; G06K7/10; G06K7/10544; G06K7/10554; G06K7/10594; G06K7/10603; G06K7/10633; G06K7/10643; G06K7/10653
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
59 words
An integrated optical resonator, comprising: a silicon substrate, a cantilever beam affixed at one end to said substrate, at least a portion of said beam having a reflective surface, and a first bimorph actuator affixed to said cantilever beam and responsive to a first electrical stimulus, said actuator causing said beam to move in accordance with said first stimulus.
Claim 2
Dependent Claim
59 words
An integrated optical resonator, comprising: a silicon substrate, a cantilever beam affixed at one end to said substrate, at least a portion of said beam having a reflective surface, and a first bimorph actuator affixed to said cantilever beam and responsive to a first electrical stimulus, said actuator causing said beam to move in accordance with said first stimulus.
Claim 3
Dependent Claim
11 words
The resonator of claim 1, wherein said cantilever beam is silicon.
Claim 4
Dependent Claim
86 words
An integrated optical resonator, comprising: a substrate, a cantilever beam affixed at one end to said substrate, at least a portion of said beam having a reflective surface, and a first bimorph actuator affixed to said cantilever beam and responsive to a first electrical stimulus, said actuator causing said beam to move in accordance with said first stimulus, wherein said bimorph actuator comprises a plurality of stacked material layers on said cantilever beam, at least two of said first actuator's layers having unequal thermal expansion coefficients.
Claim 5
Dependent Claim
86 words
An integrated optical resonator, comprising: a substrate, a cantilever beam affixed at one end to said substrate, at least a portion of said beam having a reflective surface, and a first bimorph actuator affixed to said cantilever beam and responsive to a first electrical stimulus, said actuator causing said beam to move in accordance with said first stimulus, wherein said bimorph actuator comprises a plurality of stacked material layers on said cantilever beam, at least two of said first actuator's layers having unequal thermal expansion coefficients.
Claim 6
Dependent Claim
71 words
The resonator of claim 3, wherein said beam has a rest position and at least two of said layers comprise electrodes, said electrodes arranged such that a current flowing between them causes said first actuator to heat and said beam to move away from said rest position, and a reduction in current flowing between said electrodes causes said first actuator to cool and said beam to move towards said rest position.
Claim 7
Dependent Claim
17 words
The resonator of claim 4, wherein said electrodes comprise gold with a thin titanium film adhesion layer.
Claim 8
Dependent Claim
20 words
The resonator of claim 4, wherein one of said layers comprises a bimorph material which is sandwiched between said electrodes.
Claim 9
Dependent Claim
12 words
The resonator of claim 6, wherein said bimorph material comprises zinc oxide.
Claim 10
Dependent Claim
19 words
The resonator of claim 6, wherein said bimorph material has a resistivity of 10 3 to 10 4 Ω-cm.
Claim 11
Dependent Claim
67 words
The resonator of claim 3, further comprising a second bimorph actuator affixed to said cantilever beam and responsive to a second electrical stimulus, said second actuator causing said beam to move in accordance with said second stimulus, said first and second actuators each comprising a respective plurality of stacked material layers on said cantilever beam, each actuator including at least two layers having unequal thermal expansion coefficients.
Claim 12
Dependent Claim
80 words
The resonator of claim 9, wherein said beam has a rest position and three of said layers comprise first, second and third electrodes, said first and second electrodes comprising the top layers of said first and second actuators, respectively, said electrodes arranged such that a current flowing between said first and third electrodes causes said beam to twist in a first direction and current flowing between said second and third electrodes causes said beam to twist in a second direction.
Claim 13
Dependent Claim
17 words
The resonator of claim 3, wherein said reflective surface comprises a layer of metallization forming a mirror.
Claim 14
Dependent Claim
37 words
The resonator of claim 3, wherein said beam includes a mesa structure which forms a beam section which is thicker and stiffer than the remainder of said beam and said reflective surface is atop said mesa structure.
Claim 15
Dependent Claim
25 words
The resonator of claim 12, wherein the underside of said mesa structure includes at least one depression to reduce the weight of said cantilever beam.
Claim 16
Dependent Claim
38 words
The resonator of claim 3, wherein said cantilever beam has an associated fundamental resonant frequency and an excursion distance which varies with said stimulus, said excursion distance increased when said actuator is stimulated at said fundamental resonant frequency.
Claim 17
Dependent Claim
22 words
The resonator of claim 14, further comprising actuator excitation circuitry arranged to provide stimulation to said actuator at about said resonant frequency.
Claim 18
Dependent Claim
41 words
The resonator of claim 14, wherein said cantilever beam has an associated orthogonal resonant frequency such that, when stimulated at said orthogonal resonant frequency said beam oscillates in a direction orthogonal to that followed when stimulated at said fundamental resonant frequency.
Claim 19
Dependent Claim
35 words
The resonator of claim 16, further comprising actuator excitation circuitry arranged to provide stimulation to said actuator at both said fundamental and said orthogonal frequencies, said frequencies frequency-multiplexed, said resonator suitable for providing 2D scanning.
Claim 20
Dependent Claim
37 words
The resonator of claim 3, wherein the width of said first bimorph actuator is narrow with respect to the width of said reflective surface, said narrow actuator allowing said beam to twist easier than a wider actuator.
Claim 21
Dependent Claim
37 words
The resonator of claim 3, wherein said bimorph actuator is arranged in a U-shape, the legs of the U contacting said beam along respective edges, said contact along said edges tending to prevent said beam from twisting.
Claim 22
Dependent Claim
77 words
An integrated optical resonator, comprising: a substrate, a cantilever beam affixed at one end to said substrate, at least a portion of said beam having a reflective surface, and a first bimorph actuator affixed to said cantilever beam and responsive to a first electrical stimulus, said actuator causing said beam to move in accordance with said first stimulus, wherein said reflective surface comprises a single-surface collimator, said collimator suitable for collimating light emitted from a laser diode.
Claim 23
Dependent Claim
77 words
An integrated optical resonator, comprising: a substrate, a cantilever beam affixed at one end to said substrate, at least a portion of said beam having a reflective surface, and a first bimorph actuator affixed to said cantilever beam and responsive to a first electrical stimulus, said actuator causing said beam to move in accordance with said first stimulus, wherein said reflective surface comprises a single-surface collimator, said collimator suitable for collimating light emitted from a laser diode.
Claim 24
Dependent Claim
118 words
An integrated optical resonator, comprising: a substrate, a cantilever beam affixed at one end to said substrate, at least a portion of said beam having a reflective surface, said cantilever beam having an associated fundamental resonant frequency and an excursion distance which varies with said stimulus, said excursion distance increased when said actuator is stimulated at said fundamental resonant frequency, a first bimorph actuator affixed to said cantilever beam and responsive to a first electrical stimulus, said actuator causing said beam to move in accordance with said first stimulus, and actuator excitation circuitry arranged to provide stimulation to said actuator at about said resonant frequency, wherein said actuator excitation circuitry and said resonator are integrated on said substrate.
Claim 25
Dependent Claim
118 words
An integrated optical resonator, comprising: a substrate, a cantilever beam affixed at one end to said substrate, at least a portion of said beam having a reflective surface, said cantilever beam having an associated fundamental resonant frequency and an excursion distance which varies with said stimulus, said excursion distance increased when said actuator is stimulated at said fundamental resonant frequency, a first bimorph actuator affixed to said cantilever beam and responsive to a first electrical stimulus, said actuator causing said beam to move in accordance with said first stimulus, and actuator excitation circuitry arranged to provide stimulation to said actuator at about said resonant frequency, wherein said actuator excitation circuitry and said resonator are integrated on said substrate.
Claim 26
Dependent Claim
154 words
An integrated optical resonator, comprising: a substrate, a cantilever beam affixed at one end to said substrate, at least a portion of said beam having a reflective surface, said cantilever beam having an associated fundamental resonant frequency and an excursion distance which varies with said stimulus, said excursion distance increased when said actuator is stimulated at said fundamental resonant frequency, said cantilever beam also having an associated orthogonal resonant frequency such that, when stimulated at said orthogonal resonant frequency said beam oscillates in a direction orthogonal to that followed when stimulated at said fundamental resonant frequency, a first bimorph actuator affixed to said cantilever beam and responsive to a first electrical stimulus, said actuator causing said beam to move in accordance with said first stimulus, and actuator excitation circuitry arranged to provide stimulation to said actuator at both said fundamental and said orthogonal frequencies, said frequencies time-multiplexed, said resonator suitable for providing 2D scanning.
Claim 27
Dependent Claim
154 words
An integrated optical resonator, comprising: a substrate, a cantilever beam affixed at one end to said substrate, at least a portion of said beam having a reflective surface, said cantilever beam having an associated fundamental resonant frequency and an excursion distance which varies with said stimulus, said excursion distance increased when said actuator is stimulated at said fundamental resonant frequency, said cantilever beam also having an associated orthogonal resonant frequency such that, when stimulated at said orthogonal resonant frequency said beam oscillates in a direction orthogonal to that followed when stimulated at said fundamental resonant frequency, a first bimorph actuator affixed to said cantilever beam and responsive to a first electrical stimulus, said actuator causing said beam to move in accordance with said first stimulus, and actuator excitation circuitry arranged to provide stimulation to said actuator at both said fundamental and said orthogonal frequencies, said frequencies time-multiplexed, said resonator suitable for providing 2D scanning.
Claim 28
Dependent Claim
147 words
An integrated resonator suitable for use in an optical scanner engine, comprising: a substrate, a cantilever beam affixed at a first end to said substrate and extending freely over said substrate at a second end, at least a portion of said free end having a reflective surface, and a bimorph actuator affixed to said cantilever beam and responsive to an electrical stimulus, said actuator causing the free end of said beam to move in accordance with said stimulus, said beam being at a rest position in the absence of electrical stimulus to said actuator, said actuator including at least two electrodes arranged such that a current flowing between them causes said actuator to heat and said beam to move away from said rest position, and a reduction in current flowing between said electrodes causes said actuator to cool and said beam to move towards said rest position.
Claim 29
Dependent Claim
147 words
An integrated resonator suitable for use in an optical scanner engine, comprising: a substrate, a cantilever beam affixed at a first end to said substrate and extending freely over said substrate at a second end, at least a portion of said free end having a reflective surface, and a bimorph actuator affixed to said cantilever beam and responsive to an electrical stimulus, said actuator causing the free end of said beam to move in accordance with said stimulus, said beam being at a rest position in the absence of electrical stimulus to said actuator, said actuator including at least two electrodes arranged such that a current flowing between them causes said actuator to heat and said beam to move away from said rest position, and a reduction in current flowing between said electrodes causes said actuator to cool and said beam to move towards said rest position.
Claim 30
Dependent Claim
159 words
An integrated resonator suitable for use in an optical scanner engine, comprising: a substrate, a cantilever beam affixed at a first end to said substrate and extending freely over said substrate at a second end, at least a portion of said free end having a reflective surface, and a bimorph actuator affixed to said cantilever beam and responsive to an electrical stimulus, said actuator causing the free end of said beam to move in accordance with said stimulus, said beam being at a rest position in the absence of electrical stimulus to said actuator, said actuator including at least two electrodes arranged such that a current flowing between them causes said actuator to heat and said beam to move away from said rest position, and a reduction in current flowing between said electrodes causes said actuator to cool and said beam to move towards said rest position, wherein said actuator comprises a bimorph material layer sandwiched between said electrodes.
Claim 31
Dependent Claim
159 words
An integrated resonator suitable for use in an optical scanner engine, comprising: a substrate, a cantilever beam affixed at a first end to said substrate and extending freely over said substrate at a second end, at least a portion of said free end having a reflective surface, and a bimorph actuator affixed to said cantilever beam and responsive to an electrical stimulus, said actuator causing the free end of said beam to move in accordance with said stimulus, said beam being at a rest position in the absence of electrical stimulus to said actuator, said actuator including at least two electrodes arranged such that a current flowing between them causes said actuator to heat and said beam to move away from said rest position, and a reduction in current flowing between said electrodes causes said actuator to cool and said beam to move towards said rest position, wherein said actuator comprises a bimorph material layer sandwiched between said electrodes.
Claim 32
Dependent Claim
17 words
The resonator of claim 24, wherein said reflective surface comprises a layer of metallization forming a mirror.
Claim 33
Dependent Claim
37 words
The resonator of claim 24, wherein said beam includes a mesa structure which forms a beam section which is thicker and stiffer than the remainder of said beam and said reflective surface is atop said mesa structure.
Claim 34
Dependent Claim
24 words
The resonator of claim 24, wherein said reflective surface comprises a single-surface collimator, said collimator suitable for collimating light emitted from a laser diode.
Claim 35
Dependent Claim
33 words
The resonator of claim 24, further comprising a light source which produces a light output, said output directed at said reflective surface and producing a scanning light beam when said actuator is stimulated.
Claim 36
Dependent Claim
12 words
The resonator of claim 28, wherein said light source is a laser.
Claim 37
Dependent Claim
18 words
The resonator of claim 28, further comprising a photodetector arranged to receive light from said scanning light beam.
Claim 38
Dependent Claim
126 words
An integrated optical resonator, comprising: a substrate, a cantilever beam affixed at one end to said substrate, at least a portion of said beam having a reflective surface, said cantilever beam having an associated fundamental resonant frequency and an excursion distance which varies with said stimulus, said excursion distance increased when said actuator is stimulated at said fundamental resonant frequency, said cantilever beam also having an associated higher-order orthogonal resonant frequency such that, when stimulated at said orthogonal resonant frequency said beam oscillates in a direction orthogonal to that followed when stimulated at said fundamental resonant frequency, and a bimorph actuator affixed to said cantilever beam and responsive to a first electrical stimulus, said actuator causing said beam to move in accordance with said first stimulus.
Claim 39
Dependent Claim
126 words
An integrated optical resonator, comprising: a substrate, a cantilever beam affixed at one end to said substrate, at least a portion of said beam having a reflective surface, said cantilever beam having an associated fundamental resonant frequency and an excursion distance which varies with said stimulus, said excursion distance increased when said actuator is stimulated at said fundamental resonant frequency, said cantilever beam also having an associated higher-order orthogonal resonant frequency such that, when stimulated at said orthogonal resonant frequency said beam oscillates in a direction orthogonal to that followed when stimulated at said fundamental resonant frequency, and a bimorph actuator affixed to said cantilever beam and responsive to a first electrical stimulus, said actuator causing said beam to move in accordance with said first stimulus.
References Cited (Backward Citations)
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Cited
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 7.5 Years (Year 8) | 2006-05-10 | 2006-11-09 | 2007-05-11 | $3760.00 | Window Closed / Lapsed |
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