US4596995A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dot printer having means for correcting intensity variations
Assignee: Canon Inc
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Filing: 1984-06-14
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Granted: 1986-06-24
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Expires: 2004-06-14
Abstract
Abstract A dot printer has an LED array printer head consisting an array of LEDs, drivers for independently driving the LEDs, and time control circuits for controlling ON or OFF times of the LEDs by energizing the drivers in accordance with image data and correction data stored in a memory. The LEDs can be divided into blocks which can be sequentially driven. Variations in mechanical and electrical characteristics of the LEDs are corrected to allow formation of a high-resolution image or a halftone image.
Inventors
- 👤 Tadashi Yamakawa
- 👤 Hideaki Furukawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:31
CPC Classifications
G; G06; G06K; G06K15/00; G06K15/02; G06K15/12; G06K15/1238; G06K15/1242; G06K15/1247
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
119 words
A dot printer comprising: a recording head having a plurality of recording elements for dot-recording on a recording medium; driving means for independently driving said plurality of recording elements in accordance with image data; a plurality of timer means, each of said timer means being arranged for measuring a time that is set according to a recording characteristic of an associated one of said plurality of recording elements; and correcting means for correcting a dot recording state of each of said plurality of recording elements, said correcting means being operable to control the driving time of each of said plurality of recording elements in accordance with a timing operation of the associated one of said plurality of timer means.
Claim 2
Dependent Claim
119 words
A dot printer comprising: a recording head having a plurality of recording elements for dot-recording on a recording medium; driving means for independently driving said plurality of recording elements in accordance with image data; a plurality of timer means, each of said timer means being arranged for measuring a time that is set according to a recording characteristic of an associated one of said plurality of recording elements; and correcting means for correcting a dot recording state of each of said plurality of recording elements, said correcting means being operable to control the driving time of each of said plurality of recording elements in accordance with a timing operation of the associated one of said plurality of timer means.
Claim 3
Dependent Claim
43 words
A dot printer according to claim 1, further comprising memory means for storing recording characteristics of each of said plurality of recording elements, said plurality of timer means being arranged to be set according to the recording characteristics stored in said memory means.
Claim 4
Dependent Claim
23 words
A dot printer according to claim 1, wherein said correcting means individually increments or decrements ON times of said plurality of recording elements.
Claim 5
Dependent Claim
31 words
A dot printer according to claim 1, wherein said recording head has a plurality of light-emitting elements as said plurality of recording elements, and said recording medium is a photosensitive body.
Claim 6
Dependent Claim
101 words
A dot printer comprising: a recording head having a plurality of recording elements for dot-recording on a recording medium; driving means for sequentially driving each group of a predetermined number of recording elements of said plurality of recording elements; memory means for storing correction factors for said plurality of recording elements; latching means for latching a predetermined number of correction factors, each corresponding to a group of a predetermined number of recording elements to be driven by said driving means; and correcting means for correcting the driving of corresponding recording elements based on the correction factors latched by said latching means.
Claim 7
Dependent Claim
101 words
A dot printer comprising: a recording head having a plurality of recording elements for dot-recording on a recording medium; driving means for sequentially driving each group of a predetermined number of recording elements of said plurality of recording elements; memory means for storing correction factors for said plurality of recording elements; latching means for latching a predetermined number of correction factors, each corresponding to a group of a predetermined number of recording elements to be driven by said driving means; and correcting means for correcting the driving of corresponding recording elements based on the correction factors latched by said latching means.
Claim 8
Dependent Claim
22 words
A dot printer according to claim 5, wherein said driving means drives said plurality of recording elements in accordance with image data.
Claim 9
Dependent Claim
23 words
A dot printer according to claim 5, wherein said correcting means individually increments or decrements ON times of said plurality of recording elements.
Claim 10
Dependent Claim
28 words
A dot printer according to claim 5, wherein said recording head has light-emitting elements as said plurality of recording elements, and said recording medium is a photosensitive body.
Claim 11
Dependent Claim
31 words
A dot printer according to claim 8, wherein said plurality of recording elements are light-emitting elements capable of emitting light upon being energized, and said recording medium is a photosensitive body.
Claim 12
Dependent Claim
105 words
A dot printer comprising: a recording head having a plurality of recording elements for dot-recording on a recording medium; entering means for entering image data indicating operation or non-operation of each of said plurality of recording elements; memory means for storing time data as to an operational time for each of said plurality of recording elements; and driving means for independently and selectively driving said plurality of recording elements based on the entered image data, said driving means being operable to control an operational time for said recording elements based on the image data in accordance with the time data stored in said memory means.
Claim 13
Dependent Claim
105 words
A dot printer comprising: a recording head having a plurality of recording elements for dot-recording on a recording medium; entering means for entering image data indicating operation or non-operation of each of said plurality of recording elements; memory means for storing time data as to an operational time for each of said plurality of recording elements; and driving means for independently and selectively driving said plurality of recording elements based on the entered image data, said driving means being operable to control an operational time for said recording elements based on the image data in accordance with the time data stored in said memory means.
Claim 14
Dependent Claim
33 words
A dot printer according to claim 5, wherein said correcting means is operable to control the operating time of the corresponding recording elements based on the correction factors latched by said latching means.
Claim 15
Dependent Claim
21 words
A dot printer according to claim 10, wherein said driving means individually controls ON times of said plurality of recording elements.
Claim 16
Dependent Claim
36 words
A dot printer according to claim 10, wherein said driving means is operable based on the time data read out from said memory means in synchronism with entry of the image data from said entering means.
References Cited (Backward Citations)
US4455578A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-06-23 | 1989-12-23 | 1990-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-23 | 1993-12-23 | 1994-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-23 | 1997-12-23 | 1998-06-24 | $7700.00 | Window Closed / Lapsed |