US3762791A
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Light beam deflection
Assignee: Texas Instruments Inc
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Filing: 1971-03-30
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Granted: 1973-10-02
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Expires: 1991-03-30
Abstract
Abstract A light beam is deflected into a pattern represented by a synthesized sawtooth waveform by means of a light switch and a triangular wave generator. In a video display application, a light switch directs an intensity modulated light beam along one of two paths. When directed along either path, the modulated light beam is incident upon one or the other of a mirror pair. One mirror of the pair reflects a light beam incident thereon from along a first path to the second mirror for reflection therefrom in a pattern approximated by a triangular wave, and the second mirror of the pair reflects a light beam incident thereon from along the second path to the first mirror for reflection therefrom in a pattern approximated by a triangular wave displaced 180* from the first pattern. To generate the approximated triangular waves, the first mirror of the pair oscillates at a frequency omega to deflect a light beam incident thereon in a pattern represented by the expression (sin omega t) and the second pair oscillates at a frequency 3 omega to deflect a light beam incident thereon in a pattern represented by the expression (sin 3 omega t), where omega equals the fundamental frequency. The mirrors oscillate in a manner such that the individual patterns produced are optically added. To generate the sawtooth function, only the positive going portion of the triangular wave is selected and the resultant scan patterns are interlaced on the screen.
Inventors
- 👤 G Fournier
- 👤 C Baker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:27
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/74; G; G02; G02B; G02B5/00; G02B5/08
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
121 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform comprising: means for switching a light beam incident thereon in a first and second direction, means for reflecting a light beam from said means for switching and received from said first direction in a first pattern approximated by a first triangular wave defined by -K1 sin omega t + K2 sin 3 omega t, and in a second pattern approximated by a second triangular wave displaced 180* from the first triangular wave when received from said second direction and defined by K3 sin omega t - K4 sin 3 omega t, where omega is the fundamental frequency of the reflecting means and K1- K4 are constants.
Claim 2
Dependent Claim
121 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform comprising: means for switching a light beam incident thereon in a first and second direction, means for reflecting a light beam from said means for switching and received from said first direction in a first pattern approximated by a first triangular wave defined by -K1 sin omega t + K2 sin 3 omega t, and in a second pattern approximated by a second triangular wave displaced 180* from the first triangular wave when received from said second direction and defined by K3 sin omega t - K4 sin 3 omega t, where omega is the fundamental frequency of the reflecting means and K1- K4 are constants.
Claim 3
Dependent Claim
90 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform as set forth in claim 1 wherein said reflecting means includes an oscillating mirror pair, one of said mirrors reflecting a light beam incident thereon from said first direction to the second of said mirrors for reflection therefrom to approximate said first triangular wave, and the second of said mirrors reflecting a light beam incident thereon from said second direction to the first of said mirrors for reflection therefrom to approximate said second triangular wave.
Claim 4
Dependent Claim
77 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform as set forth in claim 2 wherein one mirror of said mirror pair oscillates at a frequency omega to reflect a light beam incident thereon in a pattern represented by (sin omega t) and the second mirror of said pair operates at a frequency 3 omega to reflect a light beam incident thereon in a pattern represented by (sin 3 omega t).
Claim 5
Dependent Claim
59 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform as set forth in claim 1 wherein said switching means includes an oscillating mirror pair, one of said mirrors reflecting a light beam incident thereon to the second of said mirrors for reflection therefrom along the first and second directions to said reflecting means.
Claim 6
Dependent Claim
88 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform as set forth in claim 4 wherein one mirror of said pair oscillates at a frequency omega to reflect a light beam incident thereon in a pattern represented by (sin omega t) and the second mirror oscillates at a frequency 3 omega to reflect a light beam incident thereon in a pattern represented by (sin 3 omega t) and the mirrors oscillate in a direction such that the light beams are optically added.
Claim 7
Dependent Claim
120 words
Apparatus for scanning a light beam in a pattern approximated by a triangular wave comprising: a mirror pair, one mirror of said pair reflecting a light beam incident thereon to a second mirror of said pair for reflection therefrom, first means for harmonically oscillating one of The mirrors of said pair at a frequency omega to reflect a light beam incident thereon defined by (sin omega t), and second means for harmonically oscillating the other mirror of said pair at a frequency 3 omega to reflect a light beam incident thereon defined by (sin 3 omega t), where omega equals the fundamental harmonic of the approximated triangular wave and said mirrors oscillate to optically add the light beams reflected therefrom.
Claim 8
Dependent Claim
120 words
Apparatus for scanning a light beam in a pattern approximated by a triangular wave comprising: a mirror pair, one mirror of said pair reflecting a light beam incident thereon to a second mirror of said pair for reflection therefrom, first means for harmonically oscillating one of The mirrors of said pair at a frequency omega to reflect a light beam incident thereon defined by (sin omega t), and second means for harmonically oscillating the other mirror of said pair at a frequency 3 omega to reflect a light beam incident thereon defined by (sin 3 omega t), where omega equals the fundamental harmonic of the approximated triangular wave and said mirrors oscillate to optically add the light beams reflected therefrom.
Claim 9
Dependent Claim
33 words
Apparatus for scanning a light beam in a pattern approximated by a triangular wave as set forth in claim 6 wherein: the oscillating means for said mirror pair comprises a torsional magnetostrictive drive.
Claim 10
Dependent Claim
201 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform comprising: a first mirror pair, one mirror of said first pair reflecting a light beam incident thereon in a first direction to the second mirror of said first pair for reflection therefrom in a first pattern approximated by a triangular wave, and the second mirror of said first pair reflecting a light beam incident thereon from a second direction to the first mirror for reflection therefrom in a second pattern approximated by a triangular wave displaced 180* from the first pattern when received along a second path, a second mirror pair, one mirror of said second pair reflecting a light beam incident thereon to the second mirror of said second pair for reflection therefrom between said first and second directions to said first mirror pair, and means for individually oscillating the mirrors of said second mirror pair to reflect the light beam therefrom between the first and second directions in a manner such that the time said light beam remains along each of said two directions approximately equals the time required for the light beam to be reflected between opposite peaks of the approximated triangular waves.
Claim 11
Dependent Claim
201 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform comprising: a first mirror pair, one mirror of said first pair reflecting a light beam incident thereon in a first direction to the second mirror of said first pair for reflection therefrom in a first pattern approximated by a triangular wave, and the second mirror of said first pair reflecting a light beam incident thereon from a second direction to the first mirror for reflection therefrom in a second pattern approximated by a triangular wave displaced 180* from the first pattern when received along a second path, a second mirror pair, one mirror of said second pair reflecting a light beam incident thereon to the second mirror of said second pair for reflection therefrom between said first and second directions to said first mirror pair, and means for individually oscillating the mirrors of said second mirror pair to reflect the light beam therefrom between the first and second directions in a manner such that the time said light beam remains along each of said two directions approximately equals the time required for the light beam to be reflected between opposite peaks of the approximated triangular waves.
Claim 12
Dependent Claim
181 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform as set forth in claim 8 wherein: one mirror of said first pair oscillates at a frequency omega to reflect a light beam incident thereon in a pattern represented by (sin omega t) and the second mirror of said first pair oscillates at a frequency 3 omega to reflect a light beam incident thereon in a pattern represented by (sin 3 omega t), where omega equals a fundamental harmonic frequency and the mirrors oscillate to optically add the patterns of said first pair, and one mirror of said second pair oscillates at a frequency omega to reflect a light beam incident thereon in a pattern represented by (sin omega t) and the second mirror of said second pair oscillates at a frequency 3 omega to reflect a light beam incident thereon in a pattern represented by (sin 3 omega t), where omega equals a fundamental harmonic frequency and the mirrors oscillate in a direction to optically add the individual patterns to produce a synthesized square wave.
Claim 13
Dependent Claim
41 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform as set forth in claim 9 including oscillating means connected to each mirror of said first pair for oscillating the individual mirrors at the desired frequency.
Claim 14
Dependent Claim
29 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform as set forth in claim 10 wherein said oscillating means includes torsional magnetostrictive drives.
Claim 15
Dependent Claim
243 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform comprising: means for switching a light beam incident thereon between a first direction and a second direction, a first scanning mirror for reflecting the light beam from said first direction into first and second subdirections, a first mirror pair, one mirror of said first pair reflecting a light beam incident thereon from said first subdirection to the second mirror of said first pair for reflection tHerefrom in a first pattern approximated by a first sinusoidal function, and the second mirror of said first pair reflecting a light beam incident thereon from said second subdirection to the first mirror for reflection therefrom in a second pattern approximated by a sinusoidal function displaced 180* from the first sinusoidal function, a second scanning mirror for reflecting the light beam from the second direction into a third and a fourth subdirection, and a second mirror pair, one mirror of said second pair reflecting a light beam incident thereon from along the third subdirection to the second mirror of said second pair for reflection therefrom in a third pattern approximated by a third sinusoidal function displaced 90* from the first sinusoidal function, and the second mirror of said second pair reflecting a light beam incident thereon from the fourth subdirection to the first mirror for reflection therefrom in a fourth pattern approximated by a sinusoidal function displaced 180* from the third sinusoidal function.
Claim 16
Dependent Claim
243 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform comprising: means for switching a light beam incident thereon between a first direction and a second direction, a first scanning mirror for reflecting the light beam from said first direction into first and second subdirections, a first mirror pair, one mirror of said first pair reflecting a light beam incident thereon from said first subdirection to the second mirror of said first pair for reflection tHerefrom in a first pattern approximated by a first sinusoidal function, and the second mirror of said first pair reflecting a light beam incident thereon from said second subdirection to the first mirror for reflection therefrom in a second pattern approximated by a sinusoidal function displaced 180* from the first sinusoidal function, a second scanning mirror for reflecting the light beam from the second direction into a third and a fourth subdirection, and a second mirror pair, one mirror of said second pair reflecting a light beam incident thereon from along the third subdirection to the second mirror of said second pair for reflection therefrom in a third pattern approximated by a third sinusoidal function displaced 90* from the first sinusoidal function, and the second mirror of said second pair reflecting a light beam incident thereon from the fourth subdirection to the first mirror for reflection therefrom in a fourth pattern approximated by a sinusoidal function displaced 180* from the third sinusoidal function.
Claim 17
Dependent Claim
92 words
Apparatus for scanning a light beam in a pattern represented by a synthesized sawtooth waveform as set forth in claim 12 wherein said first scanning mirror and the mirrors of said second pair oscillate at a frequency omega /4 to deflect a light beam incident thereon in a pattern represented by + or - sin( omega /4)t, and the scanning mirror and the mirrors of said first pair oscillate at a frequency omega /4 to deflect a light beam incident thereon in a pattern represented by + or -cos ( omega /4)t.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-01 | 1977-04-02 | 1977-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-01 | 1981-04-02 | 1981-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-01 | 1985-04-02 | 1985-10-02 | $7700.00 | Window Closed / Lapsed |