Patent US3771850A successfully refreshed from Google Patents.
US3771850A
Expired / Lapsed
US
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Scan angle multiplier of constant aperture
Assignee: International Business Machines Corp
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Filing: 1971-08-04
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Granted: 1973-11-13
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Expires: 1991-08-04
Abstract
Abstract A method and apparatus are described for increasing the scan angle of a light deflector without a corresponding decrease in effective aperture. By imaging a deflector back upon itself, the resultant multiple reflections produce an enhancement of the scan angle. The scan angle multiplier is particularly applicable to refective deflectors where the resolution is limited by the deflection angle. The device comprises two mirrors and two lenses separated by the sum of their focal lengths. One or both of the mirrors pivot about the focal points of their associated lenses. The input mirror is positioned so that its normal is at an angle from the axis of the lenses, while the normal of the second mirror is parallel to the axis.
Inventors
- 👤 D Casler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:09
CPC Classifications
G; G02; G02B; G02B26/00; G02B26/08; G02B26/10
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
100 words
A scan-angle multiplier having a constant aperture, comprising: a. a light deflector for receiving an incident portion of a light ray at a predetermined location; b. means for returning said light ray to said predetermined location for a controllable constant number of passes; and c. means for transmitting said ray between said deflector and said returning means, said transmitting means and said returning means being disposed with respect to said deflector so as to control said constant number of passes and such that substantially all of said ray exits from said multiplier upon completion of said constant number of passes.
Claim 2
Dependent Claim
100 words
A scan-angle multiplier having a constant aperture, comprising: a. a light deflector for receiving an incident portion of a light ray at a predetermined location; b. means for returning said light ray to said predetermined location for a controllable constant number of passes; and c. means for transmitting said ray between said deflector and said returning means, said transmitting means and said returning means being disposed with respect to said deflector so as to control said constant number of passes and such that substantially all of said ray exits from said multiplier upon completion of said constant number of passes.
Claim 3
Dependent Claim
21 words
A scan-angle multiplier as recited in claim 1, wherein said deflector is pivotable about a first axis for scanning said ray.
Claim 4
Dependent Claim
25 words
A scan-angle multiplier as recited in claim 1, wherein said returning means is adapted to return said ray substantially symmetrically about a further predetermined location.
Claim 5
Dependent Claim
29 words
A scan-angle multiplier as recited in claim 1, wherein said deflector is movable about a second axis non-collinear with said first axis for determining said constant number of passes.
Claim 6
Dependent Claim
64 words
A scan-angle multiplier as recited in claim 3, wherein said transmitting means includes a first lens spaced from said deflector by a distance equal to its focal length and a second lens spaced from said returning means a distance equal to its focal length, said first and second lenses being spaced from each other a distance equal to the sum of their focal lengths.
Claim 7
Dependent Claim
21 words
A scan-angle multiplier as recited in claim 5, wherein said first axis passes through the focal point of said first lens.
Claim 8
Dependent Claim
52 words
A scan-angle multiplier as recited in claim 4, wherein said transmitting means comprises a first and second lens having a common axis and wherein said returning means comprises a mirror perpendicular to said common axis and spaced from said second lens a distance equal to the focal length of said second lens.
Claim 9
Dependent Claim
31 words
A scan-angle multiplier as recited in claim 7, wherein said second lens is spaced from said first lens a distance equal to the sum of the focal lengths of said lenses.
Claim 10
Independent Claim
102 words
A method of multiplying the scan angle of a light deflector while maintaining a constant aperture, comprising the steps of: a. receiving a light ray at a first predetermined location; b. scanning said light deflector about a scanning axis so as to sweep said ray recurringly through an angle; c. setting a scan-angle gain to one value of a plurality of discrete values; d. returning substantially all of said ray to said first location a fixed number of times, said fixed number being determined by said one gain value; and e. thereafter, transmitting substantially all of said ray out of said multiplier.
Claim 11
Independent Claim
102 words
A method of multiplying the scan angle of a light deflector while maintaining a constant aperture, comprising the steps of: a. receiving a light ray at a first predetermined location; b. scanning said light deflector about a scanning axis so as to sweep said ray recurringly through an angle; c. setting a scan-angle gain to one value of a plurality of discrete values; d. returning substantially all of said ray to said first location a fixed number of times, said fixed number being determined by said one gain value; and e. thereafter, transmitting substantially all of said ray out of said multiplier.
Claim 12
Dependent Claim
30 words
The method of claim 9, wherein the step of setting said scan-angle gain comprises tilting said deflector about a gain axis, said gain axis being noncollinear with said scanning axis.
Claim 13
Dependent Claim
26 words
The method of claim 10, wherein said plurality of discrete values comprises the set of integers greater than one and less than a predetermined maximum integer.
Claim 14
Dependent Claim
21 words
The method of claim 9, wherein said ray is returned to said first location substantially symmetrically about a second predetermined location.
Claim 15
Dependent Claim
65 words
The method of claim 12, wherein the step of returning said ray comprises the steps of: i. passing said ray through first and second lenses so as to focus said ray onto said second location; ii. reflecting said ray from a mirror disposed at said second location; and iii. returning said ray through said lenses so as to focus said ray onto said first location.
Claim 16
Dependent Claim
22 words
The method of claim 13, wherein said lenses are disposed on a common axis intersecting both said first and said sEcond locations.
Claim 17
Dependent Claim
47 words
The method of claim 13, wherein said first and second locations are spaced from said first and second lenses by distances equal to their respective focal lengths, and wherein said lenses are spaced from each other by a distance equal to the sum of their focal lengths.
Claim 18
Dependent Claim
21 words
The method of claim 9, wherein the step of scanning said deflector comprises oscillating a first mirror about said scanning axis.
Claim 19
Dependent Claim
25 words
The method of claim 16, wherein the step of receiving said ray comprises reflecting said ray from said mirror through an angle less than 180*.
Claim 20
Dependent Claim
26 words
The method of claim 16, wherein the step of receiving said ray comprises reflecting said ray from a second mirror through an angle less than 180*.
Claim 21
Dependent Claim
34 words
The method of claim 18, wherein the step of scanning said deflector further comprises the step of oscillating said second mirror about a further scanning axis, said scanning axes being perpendicular to each other.
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) | 1976-11-12 | 1977-05-14 | 1977-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-12 | 1981-05-14 | 1981-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-12 | 1985-05-14 | 1985-11-13 | $7700.00 | Window Closed / Lapsed |