JPH04142860A - Contact type image sensor - Google Patents

Abstract

PURPOSE:To eliminate waste of power and time by providing a signal generating means generating an operation start signal received selectively to each input terminal of N-sets of sensor chips. CONSTITUTION:N sets of sensor chips 1 are arranged in the main scanning direction, and each of the N sets of sensor chips 1 has an input terminal 4 receiving an operation start signal and an output terminal 5 outputting an operation end signal and the sensor is provided with a signal generating means in which electric connection is made so that an operation end signal outputted from an i-th sensor chip 1 is inputted to an (i+1)th sensor chip 1 as an operation start signal and generates the operation start signal received selectively to each of the input terminals 4. Thus, a start signal from a control circuit is fed selectively to an input pad 4 of each line sensor 1 and the line sensor 1 is driven so that no read is implemented for an area at the outside of an original. Thus, waste of power and time is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a contact type image sensor used mainly in information processing apparatuses for reading originals such as facsimile machines and copying machines.

[Prior Art] A contact type multi-dip image sensor is employed in a conventional document reading information processing apparatus using a short focus imaging element array. For example, in an original reading device as shown in FIGS. 11 to 16, a transparent glass plate 201 that is in contact with the original surface is attached to the top surface of a box 200, and the output light 212
The LED 211 illuminates the substrate 2 at a predetermined angle so that
An optical system 209 is arranged in the box 200 and passes the reflected light 213 of the transparent glass plate 201, and a plurality of optical systems are provided on the substrate 19 corresponding to the optical system 209. A line sensor 1 is provided inside a box 200. The above-mentioned optical system employs, for example, the above-mentioned short focus imaging element array represented by the product name "Selfoc Lens Array" (manufactured by Nippon Sheet Glass Co., Ltd.).

The line sensor I is covered with a protective film 206 on the substrate 19, and the substrate 19 is supported via a rubber plate 207 by a bottom plate 205 engaged with a box.

Note that end plates 203 are attached to screws 20 at both ends of the box 200.
It is installed in 4. Further, the box 200 is provided with a connector 202 for inputting/outputting power, control signals, etc. external to the main body of the facsimile, for example.

As shown in FIG. 17, the line sensor 1 is provided with human output pads 4.5 at both ends, and is arranged on the substrate 19 in a straight line from the first to the Nth, respectively.
By inputting a start signal as an operation start signal through the input pad 4 and outputting an end signal as an operation end signal through the output pad 5, they are sequentially activated in accordance with the arrangement order and read optical information. I have to. In this case, when outputting the end signal through the output pad 5, the end signal can be input to the input pad 4 as an operation start signal for operating the next line sensor, that is, as a start signal for the next line sensor. ing. Each line sensor 1 has a light receiving window 2 as shown in FIG.
27LLm (for 200DPI) or 63.
They are provided at a pitch of 5 μm (in the case of 400 DPI) (here, DPI is an abbreviation for Dots per 1 nch), and in addition to this, on the board LA, there are line sensor drive circuits, shift registers, power input pads, Area 3 is prepared where sensor output pads and the like are placed.

As shown in FIGS. 19 and 20, such a contact type multi-chip image sensor (indicated here by reference numeral 110) is disposed, for example, at a document reading position of a facsimile via a fixture 109. Here, a document insertion slot 103 is provided at the front edge of the facsimile main body 100, and a slit 105 is formed in parallel to a guide stage 104 of this document insertion slot 103, and the slit 105 determines the insertion position of the document. A guide piece 106 is a slidable device. Further, a keyboard panel 101 and an operation message display section 107 are arranged on the front upper surface of the facsimile main body 100, and a document ejection port 102 is provided immediately behind the keyboard panel 101 and an operation message display section 107.

Then, the original 11 inserted from the original insertion slot 103
8 reaches the feeding roller 108 via the separation piece 117, and from there the platen roller 16 and the image sensor 11
0 and is discharged to the original document take-out port 102.

A roll of recording paper 114 is stored in the rear of the facsimile main body 100, and the end thereof is taken out to the outside via a platen roller 115. At the position of the platen roller 115, Recording head 1
11, information is recorded. In addition, in the figure, the code 1
12 is a facsimile system control board, and 113 is a power supply unit.

In such a configuration, when reading a document, the line sensor 1 sequentially reads from the first to the Nth document, and during this time, read data other than the document separated by the guide pieces 106 is sent to the system controller of the facsimile machine. processed and truncated.

[Problems to be Solved by the Invention] However, in the conventional example described above, when reading a document that is shorter than the detection area of the image sensor, reading is performed up to the area where there is no document as described above, so that the area outside the document is read. This results in driving the line sensor 1, consuming unnecessary power. Further, there is wasted time in reading the document, and furthermore, a data processing program or a data processing circuit is required to discard data in areas where the document does not exist.

[Means for Solving the Problems] The present invention has been made based on the above circumstances, in which N sensor chips each having a plurality of photoelectric conversion elements are arranged in the main scanning direction, and each of the N sensor chips has a plurality of photoelectric conversion elements. has an input terminal into which an operation start signal is input and an output terminal which outputs an operation end signal, and the operation end signal output from the i-th sensor chip is inputted to the j+1-th sensor chip as an operation start signal. The contact image sensor electrically connected in this manner has a signal generating means for generating an operation start signal that is selectively input to each of the input terminals of the N sensor chips.

[Function] Therefore, since the start signal from the control circuit can be selectively supplied to the input pad of each line sensor,
The above line sensor can be driven so as not to read areas outside the document, saving power and time (
It is possible to do this without complicating the data processing system.

[Example] Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 10. Note that the same reference numerals are given to the parts having the same configuration as those of the above-mentioned conventional example, and the description thereof will be omitted.

In the first embodiment shown in FIG.
The pixel bits, that is, the spacing between photoelectric conversion elements is, for example, 12
7um (200DPT). The length of the line sensor 1 in the longitudinal direction at this time is 19.73 mm.
When a plurality of line sensors 1 are arranged approximately in a straight line, in order to correct the gap between each line sensor 1,
The value is not evenly divisible by 125 μm. When 13 of these line sensors 1 are lined up, the maximum size is B4 (256
m m ) can be read.

However, code 11! From the line indicated by , a start signal is input to the start input pad 4 of the first line sensor 1 as an operation start command, and then the signal 23, 3s
From the line indicated by , the 2nd, 3rd... line sensor 1
A start signal can be input to each of the start input pads 4. In addition, in this embodiment, the end signal pad 5 of the previous line sensor 1 is connected to the end signal pad 5 of the line sensor 1 of the next stage.
is connected to the start signal pad 4 of the line sensor 1, and when no start signal is input from the outside through the line, the end signal of the line sensor 1 at the previous stage is input to the start signal pad 4 of the line sensor l at the next stage. The next line sensor is activated.

Now, for example, when reading a B4 size document, all 13 line sensors 1 need to be driven in the above embodiment. Therefore, line 1. Input an external start signal to the line, and do not input a start signal to other lines. Therefore, the end signal from the end signal output pad 5 of the preceding line sensor 1 is input as a start signal to the start signal input pad 4 of the second and subsequent line sensors 1. The end signal is output at the end of reading from the line sensor or just before the end of reading.

In addition, when reading a document smaller than B4 size, for example, A4 size (214 mm), the guide frame 10
6 in a symmetrical manner, the second to
Only the 12th line sensor 1 is driven. Therefore, the start signal is not supplied to the first line sensor 1. Then, a start signal is input from the outside to the start signal input pad 4 of the second line sensor 1. In order to prevent the start signal from being input to the 13th line sensor 1, in this embodiment, at a predetermined timing, the reset signal input pad (not shown) of the 12th line sensor 1 is connected to the reset signal. It is preferable to configure the control circuit so that the following is input. At this time, 1
No end signal is output from the second line sensor13
The th line sensor is not driven. In the above usage mode, the end signal from the preceding line sensor 1 is input as a start signal to the start signal input pad 4 of the 3rd to 12th line sensors 1, as in the case of the 34 size described above. be done.

Naturally, when reading a document smaller than A4 size, a start signal is input to line sensor 1 to be started, and a reset signal is input to the reset signal input pad of the line sensor next to line sensor l to be terminated. If this is input, the next line sensor 1 will not be driven.

In this way, according to the present invention, by providing a signal generating means for generating an operation start signal that is selectively input to the N sensor chips, it is possible to drive only any continuous line sensor l. can.

In the above embodiment, since the document insertion position is set at the center, the guide pieces 106 operate symmetrically, but if the document insertion position is set with the last line sensor 1 side as a reference, All you need to do is consider which line sensor should input only the start signal (and the reset signal does not have to be used).

In the second embodiment shown in FIG. 2, when the end signal of the previous stage is input as a start signal to the start signal input pad of the line sensor after the first driven line sensor, an external start signal is input thereto. Selected line sensor 1 may cause malfunction due to signal input.
In order to input the start signal from the outside into the input pad 4 of ``1'' instead of the end signal, there is a connection between the output pad 5 of the previous line sensor and the input pad 4 of the next line sensor. A switching circuit 6 is provided. For the switching operation of the switching circuit 6, the line 2 gW,
3. Switching control signals can be input to SW....

In the above embodiment, it is desirable that the switching circuit 6 is placed immediately before each line sensor 1. This means that the start signal input pads 4 of the second and subsequent line sensors 1 are placed one after the other in order. This is because the length of the wiring pattern on the circuit board becomes longer, and the resulting increase in capacitance makes it easier for noise to be added.

In the third embodiment shown in FIG. 3, a buffer circuit 7 is placed immediately before the switching circuit 6 on the lines 211W, 3I1w, . . . . This is to prevent sluggishness and potential drop due to wiring resistance and wiring capacitance until reaching the start signal input pad 4 of the corresponding line sensor 1 even if the wiring pattern length on the circuit board becomes long as described above. It is.

In the above embodiment, the start signal generation circuit may be provided on the chip of each line sensor l. FIG. 4 shows one aspect of this, in which a shift register,
The start signal generation circuit described above is arranged in area 13 for power input pads, other signal input pads, and the like. Further, reference numeral 12 is an output pad of the start signal generating circuit.

FIG. 5 shows a line sensor 11 having a configuration as shown in FIG.
A fourth embodiment is shown in which the line sensor is used as the first line sensor. In addition, in this embodiment, the circuit board 14''
Second, a switching circuit 20 is provided, and the line sensor 11
Output pad 1 of the internal start signal generation circuit
2 and an external start signal input line 13 can be selectively connected to the start signal input pad 4. Note that the switching circuit 20 is switched by control signals from lines 1 and 1w. In this embodiment, the structure of the second and subsequent line sensors may be the same as that of FIG. 4, or may be the structure of the line sensor 1 used conventionally.

Here again, for example, when reading a B-size original, the start signal is applied to the first line sensor 11, and when reading an A-size original, it is applied to the second line sensor 1.

In the fifth embodiment shown in FIG. 6, a board 15 on which the line sensor l is mounted is provided with only a wiring pattern, and another board 16 is provided with the switching circuit, a transmission circuit for a start signal and an end signal, and a selection circuit. Control circuit 17 including circuits etc.
is provided. Note that the substrate 16 is provided with lines 18 corresponding to the lines 13, 28, 131, 2sw, . . . described above.

Here, an example was given in which the line sensor chips are arranged in a straight line, but of course they may be arranged in a staggered manner.

When the substrate 16 is provided separately as in the above embodiment, the configuration of the document reading device (contact type multi-chip image sensor) may be as shown in FIGS. 7 and 8. here,
The substrate 16 is attached to the bottom plate 205 via screws 23, and necessary electronic components are mounted thereon. It should be noted that, as a matter of course, a connector 202' for external signals and power is provided below the board 16.

The sensor chip described above is described in U.S. Patent No. 4,791,469 issued to inventor Omi et al. and U.S. Patent No. 4,810,896 issued to inventor Tanaka et al. A type of optical sensor that provides a capacitive load to the emitter of a bipolar transistor and reads out an output signal from the emitter as a voltage is more preferably used.

As the recording means used in the information processing device of the present invention,
For example, U.S. Pat. No. 4,723,129, U.S. Pat.
Preferably, the typical structure and principle thereof are disclosed in the specification of No. 0796. This method uses a sheet in which liquid (ink) is held? ? The electrothermal conversion is performed by applying at least one drive signal that corresponds to the recorded information and causes a rapid temperature rise exceeding nucleate boiling to the electrothermal converter disposed corresponding to the Pj path. This method is effective because it generates thermal energy in the body and causes film boiling on the heat-active surface of the recording head, resulting in the formation of bubbles in the liquid (ink) in one-to-one correspondence with this drive signal. The growth and contraction of the bubble causes liquid (ink) to be ejected through the ejection opening to form a small droplet (at least one droplet).

Furthermore, as a full-line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording apparatus, the length can be increased by combining multiple recording heads as disclosed in the above-mentioned specification. Either a configuration that satisfies the above requirements or a configuration as a single recording head formed integrally may be used.

In addition, there are also replaceable chip-type recording heads that can be installed on the device body to enable electrical connection to the device body and supply of ink from the device body, or an ink tank integrated into the recording head itself. The present invention is also effective when a cartridge type recording head is used.

Further, the document reading device is attached to a facsimile machine as indicated by the reference numeral 119 in FIG. The other configurations are the same as those in the conventional explanation, so the explanation will be omitted.

In the embodiment shown in FIG. 10, the switching circuit 25 on the circuit board 22 is of a multi-stage type, and determines which line sensor to start driving only by inputting a switching control signal S from the outside. Such a configuration does not require a plurality of start signal input sections unlike the first embodiment, and the structure is simplified.

[Effects of the Invention] The present invention has been described in detail above, and since the start signal from the control circuit can be selectively supplied to the high-power pads of each line sensor, areas outside the document are not read. The above-mentioned line sensor can be driven in such a manner that waste of power and time can be saved, and the data processing system does not need to be complicated.

[Brief explanation of the drawing]

1 to 3 are schematic configuration diagrams showing each embodiment of the present invention, FIG. 4 is a schematic configuration diagram showing a chip of a line sensor according to an embodiment of the present invention, and FIGS. 5 and 6 7 is a schematic diagram showing another embodiment of the present invention, FIG. 7 is a perspective view showing an embodiment of the document reading device according to the present invention, and FIG.
FIG. 9 is a longitudinal sectional view of a facsimile machine using a document reading device according to an embodiment of the present invention, and FIG. 1O is a sectional view taken along line A-A in the figure. A schematic configuration diagram, FIG. 11 is a perspective view of a conventional document reading device, FIG. 12 is a perspective view showing the configuration of a line sensor on a board, and FIG. 13 is taken along line C-C in FIG. 12. Cross section, 14th
15 is a sectional view taken along line BB in FIG. 11, FIG. 16 is a vertical sectional perspective view of the same, FIG. 17 is a schematic configuration diagram of a conventional example, and FIG. 18 is a schematic configuration diagram of a conventional line sensor, FIG. 19 is a perspective view showing the configuration of a conventional facsimile machine, and FIG. 20 is a longitudinal cross-sectional view taken along line DD in FIG. 19. 1. 2. 3. 4. 5. 6. 7. 8-10 11, . 12. 13° 14-16 Line sensor light receiving window area Start signal input pad End signal output pad switching circuit Buffer circuit circuit board Output pad area Circuit board] 7 Area 18° Line 19. 22゜Circuit board

Claims (6)

[Claims] (1) N sensor chips having a plurality of photoelectric conversion elements are arranged in the main scanning direction, and each of the N sensor chips has an input terminal to which an operation start signal is input and an output terminal to output an operation end signal. In the contact image sensor, the N sensors are electrically connected such that an operation end signal output from the i-th sensor chip is input as an operation start signal to the i+1-th sensor chip. A contact type image sensor comprising a signal generating means for generating an operation start signal that is selectively input to each of the input terminals of the chip. (2) The contact image sensor according to claim 1, wherein a switching circuit is provided between the output terminal of the i-th sensor chip and the input terminal of the i+1-th sensor chip. (3) The contact image sensor according to claim 1, wherein the signal generating means is provided on a substrate different from the substrate on which the N sensor chips are provided. (4) The signal generating means further includes a circuit for generating a reset signal, and the sensor chip to which the reset signal is input is prohibited from outputting an operation end signal. close-contact image sensor. (5) An information processing device comprising the contact image sensor according to claim 1 and a recording head for recording image information. (6) The information processing apparatus according to claim 5, wherein the recording head is an inkjet recording head that discharges ink using thermal energy.