US5187358A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image reading device having a telecentric optical system and a blazed diffraction grating
Assignee: Canon Inc
•
Filing: 1992-05-11
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Granted: 1993-02-16
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Expires: 2012-05-11
Abstract
Abstract An image reading device includes a plural-line sensor containing plural line sensor arrays formed on a substrate, a telecentric imaging optical system for forming the image of an object on the sensor, and a blazed diffraction grating positioned in the optical path between the imaging optical system and the sensor and adapted to separate the light from the object into plural color components and to guide the color-separated light to respectively corresponding sensor arrays.
Inventors
- 👤 Michitaka Setani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 09:41
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/46; H04N1/48; H04N1/486; H04N1/488
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
24 words
An image reading device according to claim 1, wherein said imaging optical system shows a telecentric property within an emerging angle range of 10°.
Claim 2
Dependent Claim
43 words
An image reading device according to claim 1, wherein said plural-line sensor comprises a monolithic three-line sensor having three linear sensor arrays which are mutually separated by a finite distance in a direction perpendicular to the direction of array of said sensor arrays.
Claim 3
Dependent Claim
28 words
An image reading device according to claim 2, wherein said object is scanned in a sub-scanning direction which is perpendicular to the array direction of said sensor arrays.
Claim 4
Dependent Claim
24 words
An image reading device according to claim 3, wherein a sensor-bearing surface of said monolithic 3-line sensor is positioned parallel to said sub-scanning direction.
Claim 5
Dependent Claim
19 words
An image reading device according to claim 1, wherein said telecentric imaging optical system comprises a reduction optical system.
Claim 6
Dependent Claim
19 words
An image reading device according to claim 1, wherein said blazed diffraction grating comprises a linear blazed diffraction grating.
Claim 7
Dependent Claim
40 words
An image reading device according to claim 1, wherein said telecentric imaging optical system directs a principal ray of a light beam coming from a peripheral area of a finite image reading width to enter said blazed diffraction grating perpendicularly.
Claim 8
Dependent Claim
17 words
An image reading device according to claim 1, wherein said blazed diffraction grating comprises a transmissive type.
Claim 9
Dependent Claim
16 words
An image reading device according to claim 1, wherein said blazed diffraction grating comprises reflective type.
Claim 10
Dependent Claim
18 words
An image reading device according to claim 1, wherein said imaging optical system provides a same-size erect image.
Claim 11
Dependent Claim
24 words
An image reading device according to claim 1, wherein said imaging optical system shows a telecentric property within an emerging angle range of ±10%.
Claim 12
Dependent Claim
33 words
An image reading device according to claim 1, wherein said telecentric imaging optical system has an entrance pupil on a front focal plane and all principal rays emerge parallel to an optical axis.
Claim 13
Dependent Claim
63 words
An image reading device comprising: a plural-line sensor comprising plural linear sensor arrays formed on a substrate; a telecentric imaging optical system for forming an image of an object on said sensor; and a blazed diffraction grating positioned in an optical path between said imaging optical system and said sensor and adapted to separate the light from the object into plural color components.
Claim 14
Dependent Claim
63 words
An image reading device comprising: a plural-line sensor comprising plural linear sensor arrays formed on a substrate; a telecentric imaging optical system for forming an image of an object on said sensor; and a blazed diffraction grating positioned in an optical path between said imaging optical system and said sensor and adapted to separate the light from the object into plural color components.
Claim 15
Dependent Claim
42 words
An image reading device according to claim 13, wherein said plural-line sensor comprises a monolithic three-line sensor having three linear sensor arrays which are mutually separated by a finite distance in a direction perpendicular to an array direction of said sensor arrays.
Claim 16
Dependent Claim
28 words
An image reading device according to claim 14, wherein said object is scanned in a sub-scanning direction which is perpendicular to the array direction of said sensor arrays.
Claim 17
Dependent Claim
24 words
An image reading device according to claim 15, wherein a sensor-bearing surface of said monolithic three-line sensor is positioned parallel to said sub-scanning direction.
Claim 18
Dependent Claim
19 words
An image reading device according to claim 13, wherein said telecentric imaging optical system comprises a reduction optical system.
Claim 19
Dependent Claim
19 words
An image reading device according to claim 13, wherein said blazed diffraction grating comprises a linear blazed diffraction grating.
Claim 20
Dependent Claim
40 words
An image reading device according to claim 13, wherein said telecentric imaging optical system directs a principal ray of a light beam coming from a peripheral area of a finite image reading width to enter said blazed diffraction grating perpendicularly.
Claim 21
Dependent Claim
18 words
An image reading device according to claim 13, wherein said blazed diffraction grating comprises a transmissive type grating.
Claim 22
Dependent Claim
18 words
An image reading device according to claim 13, wherein said blazed diffraction grating comprises a reflective type grating.
Claim 23
Dependent Claim
18 words
An image reading device according to claim 13, wherein said imaging optical system provides a same-size erect image.
Claim 24
Dependent Claim
24 words
An image reading device according to claim 13, wherein said imaging optical system has a telecentric property within an emerging angle range of ±10°.
Claim 25
Dependent Claim
33 words
An image reading device according to claim 13, wherein said telecentric imaging optical system has an entrance pupil on a front focal plane and all principal rays emerge parallel to an optical axis.
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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) | 1996-02-16 | 1996-08-17 | 1997-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-02-16 | 2000-08-17 | 2001-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-02-16 | 2004-08-17 | 2005-02-16 | $7700.00 | Window Closed / Lapsed |