JPH1051602A - Linear sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a linear sensor simplifying the circuit constitution of the whole external circuit and reducing the cost by reducing the number of output pins. SOLUTION: The linear sensor of color two-outputs and black-and-white two-outputs, which is provided with a color sensor part 10 and a black-and-white sensor part 20, is provided with selecting switches 31 and 32 inputting the signal of G of and the successive R/B point signal of the part 10 as one input of each and the odd-numbered pixel signal and the even-numbered pixel signal of the part 20 as the other input of each to selectively output the signal of a color system and the signal of a black-and-white signal according to each mode.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear sensor for outputting one-dimensional image information as a time-series electric signal, and more particularly to a color sensor having both a color sensor unit and a monochrome sensor unit. The present invention relates to a black and white linear sensor.

[0002]

2. Description of the Related Art Linear sensors are often used in peripheral devices such as personal computers, that is, scanners for inputting images on a display. Linear sensors include a monochrome linear sensor and a color linear sensor. Among these, a color-ready linear sensor can read a black-and-white document by using, for example, a green-ready sensor unit. However, since the linear sensor for color is less sensitive than the linear sensor for black and white because the color filter exists on the light receiving surface,
When reading at a high speed, a linear sensor that supports black and white with high sensitivity is more advantageous. Further, when reading a text document, since there are many monochrome modes, there is a strong demand for higher resolution.

For this reason, a color / monochrome linear sensor having both a color sensor unit and a monochrome sensor unit has been proposed.
123158). This publication discloses a four-line color / monochrome linear sensor composed of a three-color sensor unit for R (red), G (green), and B (blue) and a one-line sensor unit for black and white. It has been disclosed.

[0004]

However, in a conventional color / monochrome linear sensor equipped with both a color sensor unit and a monochrome sensor unit, an output signal is output to each line (outside the chip). Since the number of output pins (terminal pins of the IC) increases, and it is necessary to provide an external circuit such as an amplifier for each output pin, the circuit configuration of the entire external circuit is complicated. And the cost increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object to reduce the number of output pins and to simplify the circuit configuration of the entire external circuit and reduce costs. It is an object of the present invention to provide an improved linear sensor.

[0006]

A linear sensor according to the present invention has a first sensor unit for color and a second sensor unit for black and white.
And a selection switch that receives the output signal of the first sensor unit and the output signal of the second sensor unit as two inputs, and selectively outputs one of the two inputs. Has become.

In the linear sensor having the above configuration, the first sensor unit is used when reading a color original, and the second sensor unit is used when reading a black and white original. The selection switch selects an output signal of the first sensor unit when reading a color document, and selects an output signal of the second sensor unit when reading a monochrome document. As a result, the output signal of the first sensor unit and the second
Only one of the output signals of the sensor units is output. Therefore, one output pin can be dealt with by providing one output pin for two output signals.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram showing a first embodiment of the present invention when applied to a color 2 output / black and white 2 output linear sensor. In FIG. 1, in the linear sensor according to the first embodiment, a color-capable sensor unit (hereinafter, referred to as a color sensor unit) 10 has two lines and two outputs, and a monochrome-capable sensor unit (hereinafter, referred to as a monochrome sensor unit) 20. Have a configuration of one line and two outputs.

First, in the color sensor unit 10, a large number of photoelectric conversion units (pixels) 11-1 are linearly arranged, and a green (G) light is transmitted through a light receiving surface of the photoelectric conversion unit 11-1. A G sensor array 12-1 in which a filter (not shown) is arranged, and a G sensor array 12-1 which is provided adjacent to the G sensor array 12-1 and in which a photoelectric conversion unit 11-2 is displaced by a 1/2 pixel pitch Filter and B filter (both not shown) that are arranged in a shape and transmit each light of red (R) and blue (B) on the light receiving surface of the photoelectric conversion unit 11-2
Have an R / B sensor array 12-2 alternately arranged in pixel units.

On the opposite side of the G sensor array 12-1 from the R / B sensor array 12-2, a read-out gate unit 13-1 for reading out the signal charges photoelectrically converted by the photoelectric conversion unit 11-1 and the readout gate unit 13-1 The CCD analog shift register 14-1 for transferring the transferred signal charges is arranged. On the other hand, R /
On the opposite side of the B sensor array 12-2 from the G sensor array 12-1, a readout gate unit 13-2 for reading out the signal charges photoelectrically converted by the photoelectric conversion unit 11-2 is used. An analog memory 15 for temporarily accumulating and a CCD analog shift register 14-2 for transferring signal charges read through the analog memory 15 are arranged.

Here, the reason why the analog memory 15 is provided on the R / B sensor array 12-2 side will be described. The distance between the sensor centers of the sensor arrays 12-1 and 12-2 is d, the direction perpendicular to the sensor arrays 12-1 and 12-2 (vertical direction in the figure) is the sub-scanning direction, and If it is assumed that the R / B sensor array 12-2 precedes the G sensor array 12-1, one is between the start of main scanning of the R / B sensor array 12-2 and the start of main scanning of the G sensor array 12-1. Since the scanning time for the line is required, a time shift corresponding to one line occurs between the reading time of the R / B sensor array 12-2 and the reading time of the G sensor array 12-1.

In order to correct this time lag and to make the read output of the G sensor array 12-1 and the read output of the R / B sensor array 12-2 simultaneous, the preceding R / B
An analog memory 15 is provided between the readout gate section 13-2 on the sensor array 12-2 side and the CCD analog shift register 14-2. That is, the analog memory 15 accumulates signal charges read from each photoelectric conversion unit 11-2 of the R / B sensor array 12-2,
After being delayed by the time corresponding to the line, the signal is output to the CCD analog shift register 14-2.

CCD analog shift register 14-1, 1
At the transfer-side end of 4-2, for example, charge-voltage converters 16-1 and 16-2 having a floating diffusion amplifier (FDA) configuration are provided, respectively. The charge-voltage converters 16-1 and 16-2 convert the signal charges transferred by the CCD analog shift registers 14-1 and 14-2 into voltages and output the voltages. Charge-voltage converters 16-1, 16-2
Are subjected to impedance conversion by, for example, output circuits 17-1 and 17-2 having a source-follower circuit configuration, and then become both inputs of two-input selection switches 31 and 32, respectively.

In the color sensor unit 10 having such a configuration, the signal charges of the photoelectric conversion units 11-2 of the R / B sensor array 12-2 preceding the sub-scanning pass through the readout gate unit 13-2. After being temporarily stored in the analog memory 15, it is read out to the CCD analog shift register 14-2. On the other hand, the signal charge of each photoelectric conversion unit 11-1 of the subsequent G sensor array 12-1 is transferred to the readout gate unit 13-1.
Is read out directly to the CCD analog shift register 14-1 via the.

Here, since the sensor centers of the sensor array 12-1 and the R / B sensor array 12-2 are separated by a distance d, at a certain point in time, both sensor arrays 12-1 and 12-1
12-2 has read information at a position spatially separated by the distance d. However, as described above, the analog memory 15 is provided on the preceding R / B sensor array 12-2 side to delay the signal charges of the R / B sensor array 12-2 by a time corresponding to one line, thereby obtaining a CCD analog shift register. By reading the signals into the CCD 14-2, the signal charges read into the CCD analog shift registers 14-1 and 14-2 at a certain point in time become information at the same spatial position.

Then, the CCD analog shift register 1
The signal charge read out to 4-1 is the shift register 1
After being sequentially transferred by 4-1, the charge-voltage conversion unit 16-1 converts the voltage into a voltage to become a G output signal. On the other hand, the signal charges read out to the CCD analog shift register 14-2 are sequentially transferred by the shift register 14-2, then converted into a voltage by the charge-voltage converter 16-2, and sequentially converted to R / B points. Output signal. At this time, the G output signal and the R / B point-sequential output signal are synchronized by the one-line delay in the analog memory 15 described above.
The signal is input to one of the selection switches 31 and 32 via 1 and 17-2.

On the other hand, the monochrome sensor unit 20 is
1 is linearly arranged at a pixel pitch of 1/2 of the pixel pitch of the G sensor array 12-1 and the R / B sensor array 12-2 of the color sensor unit 10, that is, twice (W) (white). ) The sensor array 22 is provided. Since the pixel density of the W sensor array 22 is twice that of the color sensor unit 10 as described above, the monochrome sensor unit 20 has twice the resolution of the color sensor unit 10.

On one side of the W sensor array 22, a readout gate unit 23-1 for reading out signal charges photoelectrically converted by the odd-numbered photoelectric conversion units 21o of the W sensor array 22.
And a CCD analog shift register 24-1 for transferring the read signal charges.
Readout gate unit 2 for reading out the signal charges photoelectrically converted by the even-numbered photoelectric conversion units 21e of the sensor array 22
3-2 and CCD for transferring the read signal charges
An analog shift register 24-2 is provided.

As described above, even if the pixel density of the W sensor array 22 is twice that of the color sensor unit 10,
The signal charges of half of the pixels (odd-numbered photoelectric conversion units 21o / even-numbered photoelectric conversion units 21e) are read out to the CD analog shift registers 24-1 and 24-2, respectively. , 24-2 can be set to be the same as the drive frequencies of the CCD analog shift registers 14-1 and 14-2 of the color sensor unit 10. In other words, the same clock can be used as the transfer clock for the color CCD analog shift registers 14-1 and 14-2 and the monochrome CCD analog shift registers 24-1 and 24-2.

CCD analog shift registers 24-1 and 24-2
4-2, a charge-to-voltage converter 26-1, a floating diffusion amplifier, for example,
26-2 are provided. Charge-voltage converter 26
-1, 26-2 are CCD analog shift registers 24-1,
The signal charge transferred by 24-2 is converted into a voltage and output. Each output signal of the charge-voltage converters 26-1 and 26-2 is, for example, an output circuit 27- having a source follower circuit configuration.
After being subjected to impedance conversion by 1, 27-2, the other input of the selection switches 31, 32 is used. Selection switch 3
Output terminals 1 and 32 are output pins (terminal pins of IC) 3
3 and 34 respectively.

The selection switches 31 and 32 are connected to a mode (color / color) externally applied through a control terminal 35.
One of the two inputs is selected and output according to the (black and white) switching signal. That is, in the case of the color mode, the selection switch 31 selects the G output signal and outputs it via the output pin 33 to the outside.
The B-point sequential output signal is selected and output to the outside via the output pin 34. On the other hand, in the case of the monochrome mode, the selection switch 31 selects the output signal of the odd-numbered pixel column and
3, and the selection switch 32 selects the output signal of the even-numbered pixel column and outputs it to the outside via the output pin 34.

For output pins 33 and 34, 1
External circuits 36 and 37 are provided individually. The external circuits 36 and 37 are configured by an amplifier that amplifies output signals derived from the output pins 33 and 34, a CDS (correlated double sampling) circuit that reduces reset noise included in these output signals, and the like. . Note that, depending on the configuration of the system, a CDS circuit may not be necessary, or an A / D converter may be provided at a subsequent stage of the CDS circuit.

As described above, in the color 2 output / black and white 2 output linear sensor, the G output signal of the color sensor section 10 and the R / B point sequential output signal are respectively used as one input, and By providing the selection switches 31 and 32 for using the output signals of the odd-numbered pixels and the output signals of the even-numbered pixels as the other inputs, four outputs are required for a total of four outputs of two color outputs / two black and white outputs. Since only two output pins are required, the number of pins can be reduced.

As for the external circuit, one external circuit 36, 3 is provided for each of the two output pins 33, 34.
Since the external circuits 36 and 37 can be shared for color / black and white, the circuit configuration of the entire external circuit can be simplified and the cost can be reduced. As described above, even when the external circuit is shared for color / black and white and the structure is shared, the color sensor unit 10 and the black / white sensor unit 20 are not usually used at the same time, so that there is no problem in operation. There is no.

In the color 2 output / black and white 2 output linear sensor, the selection switches 31 and 32 can be easily switched between the color mode and the monochrome mode by the mode switching signal provided through the control terminal 35. In the color mode, the color sensor unit 10
Thereby, a color original can be read satisfactorily. On the other hand, in the black-and-white mode, since the pixel density is twice that of the color sensor unit 10, a character document or the like can be read at a higher resolution.

In the first embodiment, the case where the present invention is applied to a linear sensor having two color outputs / two black and white outputs has been described. However, the present invention is not limited to this combination. The present invention is also applicable to the following, and a specific example thereof will be described below.

FIG. 2 is a block diagram showing a second embodiment of the present invention when applied to a color 1 output / monochrome 1 output linear sensor. 2, in the linear sensor according to the second embodiment, the color sensor unit 40 outputs one line,
The black-and-white sensor unit 50 also has a configuration of one line and one output.

First, in the color sensor unit 40, a large number of photoelectric conversion units 41 are linearly arranged, and R, G,
It has an R / G / B sensor array 42 in which color filters (not shown) that transmit B light are sequentially arranged in pixel units. On one side of the R / G / B sensor array 42, a readout gate unit 43 for reading out the signal charges photoelectrically converted by the photoelectric conversion unit 41 and a CCD analog shift register 44 for transferring the read out signal charges are provided. Are located.

At the end of the CCD analog shift register 44 on the transfer destination side, for example, a charge-voltage converter 46 having a floating diffusion amplifier configuration is provided. The charge-voltage converter 46 converts the signal charge transferred by the CCD analog shift register 44 into a voltage and outputs the voltage. The output signal of the charge-voltage converter 46 is impedance-converted by, for example, an output circuit 47 having a source follower circuit configuration, and then becomes one input of a selection switch 61.

In the color sensor section 40 having such a configuration, the signal charge of each photoelectric conversion section 41 of the R / G / B sensor array 42 is transferred to the CCD via the readout gate section 43.
The data is read out to the analog shift register 44. The read signal charges are transferred to the CCD analog shift register 4.
After being sequentially transferred by step 4, the charge / voltage converter 46 converts the voltage signal into a voltage signal, which is an R / G / B point sequential output signal.

On the other hand, the monochrome sensor unit 50 is
1 has a W sensor array 52 in which many pixels are linearly arranged at the same pixel pitch as the color sensor unit 40. On one side of the W sensor array 52, a readout gate unit 53 for reading out the signal charges photoelectrically converted by the photoelectric conversion unit 51 and a CCD analog shift register 54 for transferring the read out signal charges are arranged. .

At the end on the transfer destination side of the CCD analog shift register 54, for example, a charge-voltage converter 56 having a floating diffusion amplifier configuration is provided. The charge-voltage converter 56 converts the signal charge transferred by the CCD analog shift register 54 into a voltage and outputs the voltage. The output signal of the charge-voltage converter 56 is impedance-converted by, for example, an output circuit 57 having a source follower circuit configuration, and then becomes the other input of the selection switch 61.

The output terminal of the selection switch 61 is connected to the output pin 6
2 are connected. The selection switch 61 selects and outputs one of the two inputs in accordance with a mode (color / monochrome) switching signal externally applied via a control terminal 63. That is, in the case of the color mode, the output signal of the output circuit 47 of the color sensor section 40 is selected and output to the outside via the output pin 62. In the case of the monochrome mode, the output signal of the monochrome sensor section 50 is selected. The output signal of the circuit 57 is selected and output to the outside via the output pin 62.

An external circuit 64 is connected to the output pin 62. The external circuit 64 includes an amplifier that amplifies an output signal derived from the output pin 62, a CDS circuit that reduces reset noise included in the output signal, and the like. Depending on the system configuration, CD
In some cases, the S circuit is unnecessary, and the A
A / D converter may be provided.

As described above, in the color 1 output / monochrome 1 output linear sensor, each output signal of the color sensor unit 40 and the monochrome sensor unit 50 is set to two inputs, and one of these two inputs is selected. By providing the selection switch 61 for outputting the image data, only one output pin is conventionally required for two outputs, one for color and one for black and white, so that the number of pins can be reduced.

As for the external circuit, a single external circuit 64 is provided for one output pin 62, and the external circuit 64 can be shared for color / monochrome. In addition to simplifying the configuration,
Cost reduction can be achieved. Thus, the color of the external circuit
Even when the configuration is shared and used for black and white, the color sensor unit 40 and the black and white sensor unit 50 are not usually used at the same time, so that there is no problem in operation.

In the color 1 output / monochrome 1 output linear sensor, the selection switch 61 can be easily switched between the color mode and the monochrome mode by a mode switching signal provided through the control terminal 63.
Then, in the color mode, the color original can be satisfactorily read by the color sensor unit 40. On the other hand, assuming that the light receiving area of the unit pixel of the monochrome sensor unit 50 is the same as that of the color sensor unit 30, the monochrome sensor unit 50 is more sensitive than the color sensor unit 30 by the absence of the color filter on the light receiving surface. Therefore, in the black-and-white mode, a character document or the like can be read at higher speed.

FIG. 3 is a block diagram showing a third embodiment of the present invention when applied to a color 3 output / monochrome 1 output linear sensor. 3, in the linear sensor according to the third embodiment, the color sensor unit 70 has three lines and three outputs.
The monochrome sensor unit 50 has a configuration of one line and one output.

First, in the color sensor unit 70, a large number of photoelectric conversion units 71-1 are linearly arranged, and the photoelectric conversion units 71-1
Sensor array 72-1 in which an R filter (not shown) for transmitting red (R) light is disposed on the light receiving surface of
And a predetermined distance from the R sensor array 72-1, a large number of photoelectric conversion units 71-2 are linearly arranged, and green (G) is placed on the light receiving surface of the photoelectric conversion unit 71-2. A) a G sensor array 72-2 in which a G filter (not shown) for transmitting light is disposed; and a G sensor array 72-2 is disposed at a predetermined distance from the G sensor array 72-2.
A B sensor array in which a large number of photoelectric conversion units 71-3 are linearly arranged, and a B filter (not shown) that transmits blue (B) light is disposed on a light receiving surface of the photoelectric conversion unit 71-3. 72-3.

On one side of the R sensor array 72-1 is provided a readout gate section 73-1 for reading out the signal charges photoelectrically converted by the photoelectric conversion section 71-1 and a CCD analog for transferring the readout signal charges. The shift register 74-1 is provided. Similarly, on one side of the G sensor array 72-2, a readout gate unit 73-2 for reading out the signal charges photoelectrically converted by the photoelectric conversion unit 71-2 and a CCD analog for transferring the read out signal charges are provided. A shift register 74-2 is arranged, and a readout gate unit 73-3 for reading out signal charges photoelectrically converted by the photoelectric conversion unit 71-3 and a signal read out from the readout gate unit 73-3 are provided on one side of the B sensor array 72-3. CCD analog shift register 7 for transferring charges
4-3 are arranged.

CCD analog shift registers 74-1 and 7-4
At the ends of the transfer destinations 4-2 and 74-3, for example, charge-voltage converters 76-1, 76-2 and 76-3 having a floating diffusion amplifier configuration are provided. The charge-voltage converters 76-1, 76-2, and 76-3 convert the signal charges transferred by the CCD analog shift registers 74-1, 74-2, and 74-3 into voltages and output the voltages. Each output signal of the charge-voltage converters 76-1, 76-2, 76-3 is output to, for example, an output circuit 77-1, 77-2, 77-3 having a source follower circuit configuration.
Is subjected to impedance conversion. Then, the output circuit 77-1
Is output to one input of the selection switch 91, the output signal of the output circuit 77-2 is output to the output pin 93, and the output circuit 7
The output signals of 7-3 are supplied to output pins 94, respectively.

In the color sensor unit 70 having such a configuration, the signal charge of each photoelectric conversion unit 71-3 of the B sensor array 72-3 is read out to the CCD analog shift register 74-3 by the readout gate unit 73-3. Similarly,
The signal charge of each photoelectric conversion unit 71-2 of the G sensor array 72-2 is read out to the CCD analog shift register 74-2 by the readout gate unit 73-2, and each photoelectric conversion unit of the R sensor array 72-1 is read. The signal charge of 71-1 is read out to the CCD analog shift register 74-1 by the readout gate unit 73-1.

The CCD analog shift register 7
The signal charge read out to 4-1 is stored in the shift register 7
After being sequentially transferred by 4-1, the charge-voltage converter 76-1 converts the voltage signal into a voltage signal to become an R output signal. The signal charges read to the CCD analog shift register 74-2 are sequentially transferred by the shift register 74-2, and then converted into a voltage by the charge-voltage converter 76-2 to become a G output signal. C
The signal charges read out to the CD analog shift register 74-3 are sequentially transferred by the shift register 74-3, and then converted into a voltage by the charge-voltage converter 76-3 to become a B output signal.

On the other hand, the monochrome sensor unit 80 is
1 has a W sensor array 82 in which many pixels are linearly arranged at the same pixel pitch as that of the color sensor unit 70. On one side of the W sensor array 82, a readout gate unit 83 for reading out the signal charges photoelectrically converted by the photoelectric conversion unit 81 and a CCD analog shift register 84 for transferring the read out signal charges are arranged. .

At the end of the CCD analog shift register 84 on the transfer destination side, a charge-to-voltage converter 86 having, for example, a floating diffusion amplifier configuration is provided. The charge-voltage converter 86 converts the signal charge transferred by the CCD analog shift register 84 into a voltage and outputs the voltage. The output signal of the charge-voltage converter 86 is impedance-converted by, for example, an output circuit 87 having a source follower circuit configuration, and then becomes the other input of the selection switch 91.

The output terminal of the selection switch 91 is connected to the output pin 9
2 are connected. The selection switch 91 selects and outputs one of the two inputs in accordance with a mode (color / monochrome) switching signal externally applied via a control terminal 95. That is, in the case of the color mode, the output signal of the output circuit 77-3 of the color sensor unit 70 is selected and output to the outside via the output pin 92. In the case of the black and white mode, the output signal of the monochrome sensor unit 80 is selected. Output circuit 87
And outputs it to the outside via the output pin 92.

One external circuit 96, 97, 98 is provided for each of the output pins 92, 93, 94. These external circuits 96, 97 and 98 are connected to the output pin 9
2, 93, and 94 each include an amplifier that amplifies an output signal derived from the output signal, a CDS circuit that reduces reset noise included in the output signal, and the like. In addition,
Depending on the configuration of the system, a CDS circuit may not be necessary, and an A / D converter may be provided at a subsequent stage of the CDS circuit.

As described above, in the color 3 output / monochrome 1 output linear sensor, the R output signal of the color sensor unit 40 and the output signal of the monochrome sensor unit 50 are set to two inputs, and any of the two inputs is used. By providing the selection switch 91 for selecting and outputting one of them, three output pins are required for the total of four outputs of three color output / one black and white output, which is required in the past. Can be reduced.

As for the external circuit, a single external circuit 98 may be provided for one output pin 93 for deriving two output signals, and the external circuit 98 may be shared for color / monochrome. Therefore, the circuit configuration of the entire external circuit can be simplified, and the cost can be reduced. As described above, even when a part of the external circuit is shared for color / black and white and the structure is shared, the color sensor unit 70 and the black and white sensor unit 80 are not usually used at the same time, so that there is no problem in operation. Will not come.

In the color 3 output / monochrome 1 output linear sensor, the selection switch 91 can be easily switched between the color mode and the monochrome mode by the mode switching signal provided through the control terminal 95.
In the color mode, the color original can be satisfactorily read by the color sensor unit 70. On the other hand, assuming that the light receiving area of the unit pixel of the monochrome sensor unit 80 is the same as that of the color sensor unit 70, the monochrome sensor unit 80 is more sensitive than the color sensor unit 70 by the absence of the color filter on the light receiving surface. Therefore, in the black-and-white mode, a character document or the like can be read at higher speed.

In this example, the R signal is provided as one input of the selection switch 91. However, the present invention is not limited to the R signal, and may be a G signal or a B signal. Of course.

FIG. 4 is a block diagram showing a third embodiment of the present invention when applied to a color 3 output / black and white 2 output linear sensor. 4, in the linear sensor according to the fourth embodiment, the color sensor unit 100 has three lines and three outputs, and the monochrome sensor unit 110 has one line and two outputs.

The color sensor unit 100 includes the photoelectric conversion unit 10
1-1 are linearly arrayed, and the photoelectric conversion unit 101-1
Sensor array 102-1 in which an R filter (not shown) that transmits red (R) light is disposed on the light receiving surface of
And a predetermined distance from the R sensor array 102-1. A large number of photoelectric conversion units 101-2 are linearly arranged, and green (G) is placed on the light receiving surface of the photoelectric conversion unit 101-2. G filter (not shown) that transmits light
Are arranged at a predetermined distance from the G sensor array 102-2, and a large number of photoelectric conversion units 101-3 are linearly arranged. Blue (B) on the light receiving surface of 101-3
And a B sensor array 102-3 in which a B filter (not shown) for transmitting the light is disposed.

On one side of the R sensor array 102-1 is provided a readout gate section 103-1 for reading out the signal charges photoelectrically converted by the photoelectric conversion section 101-1 and a CCD analog for transferring the readout signal charges. Shift register 10
4-1 is arranged. Similarly, the G sensor array 102
A readout gate unit 103-2 for reading out the signal charges photoelectrically converted by the photoelectric conversion unit 101-2 and a CCD analog shift register 104-2 for transferring the readout signal charges are arranged on one side of -2. And B sensor array 1
A read-out gate unit 103-3 for reading out the signal charges photoelectrically converted by the photoelectric conversion unit 101-3 is provided on one side of the readout gate unit 103-3.
And a CCD analog shift register 104-3 for transferring the read signal charges.

The CCD analog shift register 104-1,
At the end of each of the transfer destinations 104-2 and 104-3, for example, charge-to-voltage converters 106-1, 106-2, and 106-3 having a floating diffusion amplifier configuration are provided. The charge-voltage converters 106-1, 106-2, 106-3 are:
CCD analog shift registers 104-1, 104-2, 1
The signal charge transferred by 04-3 is converted into a voltage signal and output. The charge-voltage converters 106-1 and 106-2,
Each output signal of 106-3 is subjected to impedance conversion in output circuits 107-1, 107-2, and 107-3 having, for example, a source follower circuit configuration. The output signal of the output circuit 107-1 becomes one input of the selection switch 121, the output signal of the output circuit 107-2 becomes one input of the selection switch 122, and the output signal of the output circuit 107-3 becomes the output pin 125.
Supplied to

In the color sensor unit 100 having such a configuration, the signal charge of each photoelectric conversion unit 101-3 of the B sensor array 102-3 is transferred to the readout gate unit 103-3.
The data is read out to the CD analog shift register 104-3.
Similarly, each photoelectric conversion unit 101 of the G sensor array 102-2
-2 is read out to the CCD analog shift register 104-2 by the readout gate unit 103-2, and the signal charge of each photoelectric conversion unit 101-1 of the R sensor array 102-1 is read out by the readout gate unit. 103-1 by C
The data is read out to the CD analog shift register 104-1.

Then, the CCD analog shift register 1
The signal charges read out to 04-1 are sequentially transferred by the shift register 104-1 and then transferred to the charge-voltage converter 106-1.
Is converted to a voltage to become an R output signal. The signal charges read to the CCD analog shift register 104-2 are:
After being sequentially transferred by the shift register 104-2, it is converted into a voltage by the charge-voltage converter 106-2 and becomes a G output signal. The signal charges read out to the CCD analog shift register 104-3 are sequentially transferred by the shift register 104-3, then converted into a voltage by the charge-voltage converter 106-3, and become a B output signal.

On the other hand, in the monochrome sensor section 110, the photoelectric conversion section 111 has a pixel pitch of 1 for each of the R, G, and B sensor arrays 102-1, 102-2, and 102-3 of the color sensor section 100.
It has a W sensor array 112 which is linearly arranged at a pixel pitch of / 2, that is, twice the pixel density. As described above, since the pixel density of the W sensor array 112 is twice that of the color sensor unit 100, the black and white sensor unit 1
10 has twice the resolution of the color sensor unit 100.

On one side of the W sensor array 112, a readout gate unit 113-1 for reading out the signal charges photoelectrically converted by the odd-numbered photoelectric conversion units 111o of the W sensor array 112 and the readout signal charges are stored. C to transfer
A CD analog shift register 114-1 is arranged, and on the other side, a readout gate unit 113-2 for reading out signal charges photoelectrically converted by the even-numbered photoelectric conversion units 111e of the W sensor array 112 and the readout gate unit 113-2 for reading out the signal charges A CCD analog shift register 114-2 for transferring signal charges is provided.

As described above, even if the pixel density of the W sensor array 112 is twice that of the color sensor unit 100, the CCD analog shift registers 114-1 and 114-2 are used.
Have half the pixels (odd-numbered photoelectric conversion units 111
The signal charges of the o / even-numbered photoelectric conversion units 111e) are read out, so that the CCD analog shift registers 114
-1 and 114-2 are set to C of the color sensor unit 100.
The drive frequency can be set to be the same as the drive frequency of the CD analog shift registers 104-1 and 104-2. That is, CC on the color side
D analog shift registers 104-1 and 104-2 and monochrome CCD analog shift registers 114-1 and 114
The same clock can be used as the -2 transfer clock.

The CCD analog shift register 114-1,
An end of the transfer-destination side of 114-2 is, for example, a charge-to-voltage converter 11 having a floating diffusion amplifier configuration.
6-1 and 116-2 are provided respectively. The charge-voltage converters 116-1 and 116-2 convert the signal charges transferred by the CCD analog shift registers 114-1 and 114-2 into voltages and output them. Charge-voltage converter 26-1,
Each output signal of 26-2 is subjected to impedance conversion in output circuits 117-1 and 117-2 having, for example, a source follower circuit configuration, and then becomes the other input of the selection switches 121 and 122. Output terminals of the selection switches 121 and 122 are connected to output pins 1233 and 124, respectively.

Selection switches 121 and 122 select and output one of two inputs in response to a mode (color / monochrome) switching signal externally applied via control terminal 126. That is, in the case of the color mode, the selection switch 121 selects the output signal of R and outputs it to the outside through the output pin 123, and the selection switch 122 selects the output signal of G and outputs it through the output pin 124. Output to outside. On the other hand, in the case of the monochrome mode, the selection switch 121 selects the output signal of the odd-numbered pixel column and outputs it to the outside via the output pin 123.
Selects the output signal of the even-numbered pixel column and outputs it to the outside via the output pin 124.

One external circuit 127, 128, 129 is provided for each output pin 123, 124, 125.
Is provided. These external circuits 127, 128, 1
Reference numeral 29 denotes an amplifier that amplifies output signals derived from the output pins 123, 124, and 125, and a CDS circuit that reduces reset noise included in these output signals. Note that, depending on the configuration of the system, a CDS circuit may not be necessary, or an A / D converter may be provided at a subsequent stage of the CDS circuit.

As described above, in the color 3 output / black and white 2 output linear sensor, the R
And the G signal as one input, and the output signal of the odd-numbered pixel and the output signal of the even-numbered pixel of the monochrome sensor unit 110 as the other input.
1, 122, color 3 output / black and white 2
Since only three output pins are required for the total of five outputs, the number of pins can be reduced.

As for the external circuit, one external circuit 127, 128, 129 is provided for each of the three output pins 123, 124, 125. Of the three external circuits 127, 128, 129, Can be shared for color / black and white, so that the circuit configuration of the entire external circuit can be simplified and the cost can be reduced. As described above, even when the external circuit is shared for color / black and white and the configuration is shared, the color sensor unit 10 and the black / white sensor unit 20 are not usually used at the same time.
There is no hindrance.

In the color 3 output / black and white 2 output linear sensor, the selection switches 121 and 12 are switched by a mode switching signal provided through a control terminal 126.
2 can be easily switched between the color mode and the monochrome mode. In the color mode, the color original can be read favorably by the color sensor unit 100. On the other hand, in the black-and-white mode, since the pixel density is twice that of the color sensor unit 100, a character document or the like can be read at a higher resolution.

The two inputs of the selection switches 121 and 122 are not limited to the combination of this example, but may be any combination between a color signal and a monochrome signal.

Further, in each of the above embodiments, a case where the present invention is applied to a linear sensor having two outputs of color / two black and white, one output of one black / white, one output of three colors of color and one output of black and white, and three outputs of black / white and two outputs of monochrome. Although described, the present invention can be similarly applied to other combinations of linear sensors such as two color outputs / one black and white output.

[0070]

As described above, according to the present invention,
Each of the output signals of the color sensor unit and the monochrome sensor unit has two inputs, and a selection switch for selectively outputting one of the two inputs is provided. Since the number of external circuits can be reduced and color / monochrome can be shared, the circuit configuration of the entire external circuit can be simplified and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a first embodiment of the present invention when applied to a color 2 output / black and white 2 output linear sensor.

FIG. 2 is a configuration diagram illustrating a second embodiment of the present invention when applied to a color 1 output / black and white 1 output linear sensor.

FIG. 3 is a configuration diagram showing a third embodiment of the present invention when applied to a color 3 output / monochrome 1 output linear sensor.

FIG. 4 is a configuration diagram showing a fourth embodiment of the present invention when applied to a color 3 output / black and white 2 output linear sensor.

[Explanation of symbols]

10, 40, 70, 100 color sensor units 11-1, 11-2, 21, 41, 51, 71-1 to 71-3,
81, 101-1 to 101-3, 111 Photoelectric conversion units 12-1, 12-2, 22, 42, 52, 72-1 to 72-3,
82, 102-1 to 102-3, 112 Sensor array 13-1, 13-2, 23-1, 23-2, 43, 53, 73-1
~ 73-3,83,103-1 ~ 103-3,113-1,11
3-2 Lead-out gate section 14-1, 14-2, 24-1, 24-2, 44, 54, 74-1
~ 74-3,84,104-1 ~ 104-3,114-1,11
4-2 CCD analog shift register 15 Analog memory 16-1, 16-2, 26-1, 26-2, 46, 56, 76-1
~ 76-3,86,106-1 ~ 106-3,116-1,11
6-2 Charge / voltage converter 31, 32, 61, 91, 121, 122 Selection switch 33, 34, 62, 92 to 94, 123 to 125 Output pin 36, 37, 64, 96 to 98, 127 to 129 External circuit

Claims (1)

[Claims] A first sensor unit corresponding to color, a second sensor unit corresponding to black and white, and an output signal of the first sensor unit and an output signal of the second sensor unit. A selection switch for selectively outputting one of two inputs.