US4646155A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image reader for image processing apparatus
Assignee: Ricoh Co Ltd
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Filing: 1985-07-18
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Granted: 1987-02-24
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Expires: 2005-07-18
Abstract
Abstract An image reader in which a plurality of light-sensitive cells arranged in an array in a line image sensor are divided into a predetermined number of blocks, and the blocks are sequentially selected to sequentially drive the light-sensitive cells in each of the blocks to produce image signals. Charging switches are provided for charging the light-sensitive cells via block selector switches. The charging switches are activated after a signal read time assigned to each light-sensitive cell has expired to thereby shorten the charging time necessary for the light-sensitive cell. The block selector switches are each actuated at a predetermined timing while the charging switches are activated, thereby preventing noise due to switching actions of the block selector switches from being introduced into image signals.
Inventors
- 👤 Hideyuki Miyazawa
- 👤 Eiji Kamizyo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 17:33
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/04; H04N1/19; H04N1/191; H04N1/192; H04N1/193; H04N1/1931; H04N1/40; H04N1/40056
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
142 words
An image reader in which a plurality of light-sensitive cells arranged in an array in a line image sensor are divided into a predetermined number of blocks, and blocks are sequentially selected to sequentially drive the light-sensitive cells in each of the blocks to produce image signals, said image reader comprising: a means for supplying power; block selector means associated in one-to-one correspondence with the blocks for selecting one of the blocks at a time; and charging means for rapidly charging the light-sensitive cells in each selected block by way of a charge switch connected between common junction of outputs of the respective blocks and said means for supplying power; said charging means being constructed to operate in such a manner as to rapidly charge any of the light-sensitive cells after a signal read period assigned to said light-sensitive cell has expired.
Claim 2
Dependent Claim
142 words
An image reader in which a plurality of light-sensitive cells arranged in an array in a line image sensor are divided into a predetermined number of blocks, and blocks are sequentially selected to sequentially drive the light-sensitive cells in each of the blocks to produce image signals, said image reader comprising: a means for supplying power; block selector means associated in one-to-one correspondence with the blocks for selecting one of the blocks at a time; and charging means for rapidly charging the light-sensitive cells in each selected block by way of a charge switch connected between common junction of outputs of the respective blocks and said means for supplying power; said charging means being constructed to operate in such a manner as to rapidly charge any of the light-sensitive cells after a signal read period assigned to said light-sensitive cell has expired.
Claim 3
Dependent Claim
61 words
An image reader as claimed in claim 1, wherein each of block selector means comprises a selector switch connected to the light-sensitive cells in any of the blocks which is associated with said block selector means, each of the block selector means being caused to start operating when said selector switch associated with said block selector means has been turned on.
Claim 4
Dependent Claim
34 words
An image reader as claimed in claim 2, wherein the selector switches associated with the respective block selector means are each actuated at a predetermined timing during an operating period of the charging means.
Claim 5
Dependent Claim
19 words
An image reader as claimed in claim 1, further comprising an amplifier which is connected to said common junction.
Claim 6
Dependent Claim
35 words
An image reader as claimed in claim 3, wherein the charging means comprises a plurality of charge switches each of which is connected between the output of any of the blocks and a power source.
Claim 7
Dependent Claim
29 words
An image reader as claimed in claim 5, further comprising amplifiers which respectively are connected between the outputs of the blocks and the selector switches associated with said blocks.
Claim 8
Dependent Claim
30 words
An image reader as claimed in claim 5, further comprising resistors which respectively are connected in parallel with the charge switches and are connected in series with the power source.
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) | 1990-02-23 | 1990-08-25 | 1991-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-23 | 1994-08-25 | 1995-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-23 | 1998-08-25 | 1999-02-24 | $7700.00 | Window Closed / Lapsed |