US6229140B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Displacement information detection apparatus
Assignee: Canon Inc
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Filing: 1996-10-24
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Granted: 2001-05-08
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Expires: 2016-10-24
Abstract
Abstract A displacement information detection apparatus includes a light generation unit, a first unit including a first grating for displacement information detection and one or more lens members for original detection, and a second unit including a second grating for displacement detection, which cooperates with the first grating, and an origin detection mark. The apparatus also includes at least one first light-receiving element for receiving light generated by the light generation unit and propagated via the first and second gratings, and outputting a signal including relative displacement information between the first and second units. The apparatus also includes one or more second light-receiving elements for receiving light generated by the light generation unit and propagated via the lens member. The second light-receiving elements output a signal indicating an origin based on a change in light-receiving state when the origin detection mark is present in the optical path of light leaving the lens member.
Inventors
- 👤 Koh Ishizuka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:18
CPC Classifications
G; G01; G01B; G01B11/00; G01D; G01D5/00; G01D5/26; G01D5/32; G01D5/34; G01D5/36; G01D5/38; G01B11/02; G01D5/12; G01D5/244; G01D5/245; G01D5/2454; G01D5/2455; G01D5/2457
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
151 words
A displacement information detection apparatus comprising: a light generation portion; a first unit including a first grating for displacement information detection and a plurality of lens members for original detection; a second unit including a second grating for displacement detection, which cooperates with said first grating, and an origin detection mark; at least one first light-receiving element for receiving light generated by said light generation portion and propagated via said first and second gratings, and outputting a signal including relative displacement information between said first and second units; and at least one second light-receiving element for receiving light generated by said light generation portion and propagated via said plurality of lens members, said at least one second light-receiving element outputting a signal indicating an origin based on a change in light-receiving state when said origin detection mark is present in an optical path of light leaving said plurality of lens members.
Claim 2
Dependent Claim
151 words
A displacement information detection apparatus comprising: a light generation portion; a first unit including a first grating for displacement information detection and a plurality of lens members for original detection; a second unit including a second grating for displacement detection, which cooperates with said first grating, and an origin detection mark; at least one first light-receiving element for receiving light generated by said light generation portion and propagated via said first and second gratings, and outputting a signal including relative displacement information between said first and second units; and at least one second light-receiving element for receiving light generated by said light generation portion and propagated via said plurality of lens members, said at least one second light-receiving element outputting a signal indicating an origin based on a change in light-receiving state when said origin detection mark is present in an optical path of light leaving said plurality of lens members.
Claim 3
Dependent Claim
25 words
An apparatus according to claim 1 , wherein said first grating comprises a phase type diffraction grating, and said second grating comprises an amplitude grating.
Claim 4
Dependent Claim
20 words
An apparatus according to claim 2 , wherein said plurality of lens members comprises a phase type diffraction grating lens.
Claim 5
Dependent Claim
15 words
An apparatus according to claim 2 , wherein said first grating comprises a lamellar grating.
Claim 6
Dependent Claim
24 words
An apparatus according to claim 1 , wherein said plurality of lens members condenses incident light into a dot pattern or a linear pattern.
Claim 7
Dependent Claim
47 words
An apparatus according to claim 5 , wherein a width, on said second unit, of a light beam condensed by each of said plurality of lens members is designed to be not more than a width of a transmission or light-shielding portion of said origin detection mark.
Claim 8
Dependent Claim
40 words
An apparatus according to claim 1 , wherein said first and second units are arranged, so that an interval between said plurality of lens members and said origin detection mark matches a focal length of said plurality of lens members.
Claim 9
Dependent Claim
26 words
An apparatus according to claim 1 , wherein the signal indicating the origin output from said at least one second light-receiving element is a pulse signal.
Claim 10
Dependent Claim
30 words
An apparatus according to claim 8 , further comprising a circuit for converting the pulse signal output from said at least one second light-receiving element into a rectangular wave signal.
Claim 11
Dependent Claim
45 words
An apparatus according to claim 1 , wherein said origin detection mark has transparent and non-transparent patterns, and said apparatus further comprises a circuit generating a difference signal between signals output from two second light-receiving elements arranged in correspondence with the transparent and non-transparent patterns.
Claim 12
Dependent Claim
21 words
An apparatus according to claim 1 , wherein said origin detection mark has patterns corresponding to said plurality of lens members.
Claim 13
Dependent Claim
40 words
An apparatus according to claim 11 , wherein an arrangement of the plurality of patterns of said origin detection mark is substantially equal to a light beam pattern sequence projected by said plurality of lens members onto said second unit.
Claim 14
Dependent Claim
28 words
An apparatus according to claim 11 , wherein at least some of said plurality of lens members are decentered to impart directivity to light beams that pass therethrough.
Claim 15
Dependent Claim
30 words
An apparatus according to claim 1 , wherein said first grating for displacement information detection and said plurality of lens members for origin detection are arranged on a single substrate.
Claim 16
Dependent Claim
25 words
An apparatus according to claim 1 , wherein said second grating for displacement detection and said origin detection mark are arranged on a single substrate.
Claim 17
Dependent Claim
33 words
An apparatus according to claim 1 , wherein said light generation portion, said first unit, and said first and second light-receiving elements are integrated, and said second unit is movable relative to them.
Claim 18
Dependent Claim
14 words
An apparatus according to claim 16 , wherein said second unit is pivotally arranged.
Claim 19
Dependent Claim
33 words
An apparatus according to claim 1 , wherein said light generation portion, said second unit, and said first and second light-receiving elements are integrated, and said first unit is movable relative to them.
Claim 20
Dependent Claim
14 words
An apparatus according to claim 18 , wherein said first unit is pivotally arranged.
Claim 21
Dependent Claim
38 words
An apparatus according to claim 11 , wherein each of said plurality of lens members condenses light from said light generation portion so as to form a plurality of condensed lights of which intervals in arrangement are uneven.
Claim 22
Dependent Claim
20 words
An apparatus according to claim 11 , wherein said origin detection mark includes a plurality of element patterns arranged unevenly.
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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) | 2004-05-07 | 2004-11-06 | 2005-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-05-07 | 2008-11-06 | 2009-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-05-07 | 2012-11-06 | 2013-05-08 | $7700.00 | Window Closed / Lapsed |