JP2002077520A - Image reader and image processor provided with the image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for not making a user feel unpleasant without taking a long reset time including readjustment longer than needed at the time of resetting from a standby state in which power feed is partially stopped. SOLUTION: The setting values of a gain amplifier 24 and an offset adjustment circuit 25 adjusted at the time of supplying a main power source are preserved in a setting value preservation means. At the time of the resetting, when a power source part 41 is controlled and power feed stop is cancelled, the preserved setting values are set and whether or not the characteristics of the gain amplifier and the offset adjustment circuit are within a prescribed appropriate range is judged by the processing result of obtained image signals. In the case that the characteristics are within the appropriate range, the setting values are used as they are and read is executed. In the case that the characteristics are out of the appropriate range, the readjustment is performed. The readjustment can be performed only for adjustment items out of it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus and an image processing apparatus (a scanner, a copying machine, a facsimile, etc.) equipped with the image reading apparatus, and an adjustment value to be made when power is restored from a standby mode in an energy saving state. The present invention relates to an image processing apparatus capable of starting up in a use state in a short period of time by improving the efficiency of setting.

[0002]

2. Description of the Related Art Recently, environmental protection and energy saving have been taken up.
Efforts are being made to meet the proposed standards for energy saving, such as ESM. These standards aim to save energy and reduce energy consumption when in a standby state (a state in which a part of the power supply is stopped after a predetermined period of unused time after the main power is turned on and a return command is issued). There are restrictions. At present, the energy saving mode in standby mode, which is implemented in copiers, switches off the power of the operation panel and other power sources, including the fixing heater, which consumes a large amount of power, or switches to low-power operation. It is generally turned off. On the other hand, when using a copier in the standby state,
The user has to return the power supply to the on state or return from the low power operation to the normal operation state, and wait for the user to return to the usable state. This waiting time was felt longer for the user than it actually was, which led to stress. Conventionally, when returning from the standby state, the scanner unit performs the following adjustment when the power is turned on so that the obtained analog image signal is accurately converted to a digital image signal. -Adjustment of the amplification factor to amplify the analog image signal to a suitable size.・ Adjust the reference level so that the black level becomes the optimum value.

[0003]

Therefore, when the supply of power to the scanner unit is stopped in the standby state, a time for performing the above adjustment is included when returning from the standby state. There was a problem that it would lead to waiting results. The present invention has been made in view of the above-described conventional problem that in a conventional image reading apparatus in which a part of power supply is stopped in a standby state, a return time is lengthened due to including readjustment when returning from the standby state. It is an object of the present invention to provide an image reading apparatus that does not require a longer recovery time from a standby state than necessary and does not cause discomfort to a user, and an image processing apparatus including the image reading apparatus (a scanner, Copying machine, facsimile, etc.).

[0004]

According to the first aspect of the present invention, there is provided an image reading means, an image signal processing means for performing processing according to a set value to an image signal read by the image reading means,
Means for adjusting the characteristics of the image signal processing means by changing the set values of the image signal processing means; setting value storage means for storing the set values of the image signal processing means; In the image reading apparatus provided with the power control means for canceling the power supply stop state at the time of return after returning to the power supply stop state, the set value of the image signal processing means adjusted when the main power is turned on is stored in the set value storage means. When the power supply suspension state is released by the power supply control means, the set value stored in the set value storage means is set in the image signal processing means, and the characteristics of the image signal processing means are determined according to the processing result of the obtained image signal. Means for judging whether or not the image signal is within the appropriate range. When it is determined that the characteristics of the image signal processing means are within the appropriate range, the image is read using the set value as it is. An image reading apparatus being characterized in that so as to run.

According to a second aspect of the present invention, in the image reading apparatus according to the first aspect, when it is determined that the characteristic of the image signal processing means at the time of canceling the power supply stop state does not fall within an appropriate range, the image reading processing is performed. The readjustment is performed by means for adjusting the characteristics of the means.

According to a third aspect of the present invention, in the image reading apparatus according to the second aspect, when it is determined that any of the characteristics of the image signal processing means to be adjusted does not fall within an appropriate range, It is characterized in that adjustments to be made when power is turned on are performed.

According to a fourth aspect of the present invention, in the image reading apparatus according to the second aspect, the adjustment is performed only for the characteristics determined to be out of the proper range among the characteristics of the image signal processing means to be adjusted. It is characterized by the following.

According to a fifth aspect of the present invention, there is provided an image processing apparatus comprising the image reading apparatus according to any one of the first to fourth aspects.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described based on the following embodiments shown in the accompanying drawings. FIG. 1 shows a schematic configuration of an image reading apparatus according to an embodiment of the present invention. In FIG. 1, when a document is placed on a document table 1, an automatic document feeder 2 called an ADF (Auto Document Feeder) conveys the document onto a contact glass 3 arranged above the image reading device so as not to float. The document is read at this position. Contact glass 3
A white reference plate 11 having a size covering a reading area in the main scanning direction (a direction perpendicular to the plane of FIG. 1) is disposed at an end of the image processing unit 10 and is used to obtain correction data at the time of shading correction in the image processing unit 10 described later. Is done. ADF2 platen 1
A document sensor 40 for detecting that a document is set
b (see FIGS. 2 and 3), and the presence or absence of a document is determined based on the output signal of the sensor. In addition, it is also possible to manually set an original on the contact glass 3 by using an original pressing member called a thick plate without using the ADF 2. When a thick plate is used, the original provided by opening and closing the member provided with the thick plate is set.
3) so that it is possible to detect that the document is set manually.

The illumination light from the light source 4 irradiates the white reference plate 11 or the original placing surface of the contact glass 4 at a predetermined angle, and reflects the reflected light from the original or the white reference plate 11 to image information on the surface. As a reading light. The reflected light from the white reference plate or the original is converted into an image forming lens 8 by three mirrors, namely, a first mirror 5, a second mirror 6, and a third mirror 7.
To the photoelectric conversion element CC by the imaging lens 8
D is incident on the light receiving surface of a sensor board unit (hereinafter, referred to as “SBU”) 9 provided with D and forms an image. In order to scan the original and the reading surface of the white reference plate 11 with illumination light from the light source (lamp) 4, the light source 4 and the first mirror 5, and the second mirror 6 and the third mirror 7 are each provided with a carriage (not shown). )
To form a first traveling body 12 and a second traveling body 13 and drive the traveling bodies 12 and 13 by a motor 13 to maintain a constant distance between the reading surface and the CCD of the SBU 9 in the sub-scanning direction. (In the direction of the arrow shown). In the SBU 9, a voltage corresponding to the amount of incident light is detected by a CCD as an analog image signal, subjected to predetermined processing, and then transferred to the image processing unit 10 as a digital image signal.

FIG. 2 is a schematic block diagram of an image reading circuit according to an embodiment of the present invention. Figure 2 shows the CC
An image processing circuit, a power supply circuit, and a CPU 29 that controls the operation of these circuits from the image data read in D21 to the image processing and the generation of image forming data for paper output of the reproduced image by the plotter unit 35. A control circuit is shown. The configuration and operation of the circuit will be described below with reference to FIG. The CCD 21 converts the reflected light from the original into an analog image signal. Note that in FIG.
Although only one output is described from D21, there are two or four output types in a high-speed CCD. In such a case, the circuit shown in this embodiment is used for each output. Depending on the application, any number of output systems can be implemented. The analog image signal from the CCD 21 is driven by a buffer 22 and sampled and held by a sampling circuit 23 to remove high frequency components such as reset noise. The gain amplifier 24 is an amplifier whose gain can be controlled by the voltage Vg applied to the control terminal. The control voltage Vg is determined by the white peak detection circuit 3
A set value generated by the CPU 29 based on a detection value of 0 (described later) is applied via the D / A converter 31. As an example of the characteristics of the gain amplifier 24, as shown in FIG. 4, a voltage Vg for controlling the gain and the gain have a linear relationship. The offset adjustment circuit 25 has a function of giving an offset to the analog image signal with the voltage Veo or Vos applied to the control terminal. Control voltage Ve
o is applied via the D / A converter 32 to a set value for adjusting the reference level E / O difference generated by the CPU 29 based on a detection value of a black level detection circuit 27 (described later), and the control voltage Vos is also the same. The setting value for adjusting the reference level generated by the CPU 29 is applied via the D / A converter 33. As an example of the characteristics of the offset adjusting circuit 25, as shown in FIG. 5, the voltages Veo and Vos for controlling the offset and the offset amount have a linear relationship.

The A / D converter 26 converts an input analog image signal into a digital image signal at a predetermined resolution (for example, 8 bits) based on an upper limit reference value and a lower limit reference value. In order for the A / D converter 26 to operate with sufficient accuracy, the input analog image signal must be A
Widely changes between the upper reference value and the lower reference value of the / D converter 26 (changes the dynamic range)
Thus, it is necessary to adjust the gain amount in the gain amplifier 24 and the offset amount in the offset adjustment circuit 25. The black level detection circuit receives the digital image signal output of the A / D converter 26, and receives the digital image signal output from the
Has a function of capturing and storing the output level (black level) of the image signal during a period corresponding to the range of OPB (Optical Black) pixels in the above. The stored black level is an average value obtained by capturing a plurality of OPB pixels.
Is saved for each output channel. FIG. 6 shows an example of the timing chart. As shown in FIG.
There is an OPB pixel area at the beginning of the scanning period, and an operation is performed in which a digital image signal sampled, A / D converted, and output in that area is detected by an xopb signal and stored. The black level detected at this time is
9 and used for reference level adjustment by an offset adjustment circuit 25 described later. The black level subtraction circuit 28
This circuit subtracts the value stored in the black level detection circuit 27 when a digital image signal (see FIG. 6) corresponding to the range of effective pixels of D21 is input. In the image signal output of the black level subtraction circuit 28, the fluctuation of the black level is corrected.

The white peak detection circuit 30 receives the digital image signal output from the black level subtraction circuit 28 and stores the peak value of the image signal in a period corresponding to the effective pixel range of the CCD 21 indicated by the xlgate signal. Circuit. As shown in FIG. 6, a digital image signal sampled for each effective pixel range in one scanning period, A / D converted and output is extracted by an xlgate signal, and a peak value during the operation is detected and stored. Do. The white peak value detected at this time is sent to the CPU 29 and used for gain adjustment of the gain amplifier 24 described later. The shading data FIFO 35 is a memory for sequentially storing values read from the white reference plate 11 while performing processing such as averaging for each pixel, and uses the stored data for shading correction. The shading correction circuit 34 converts the read digital image data into shading data F
Correction calculation is performed based on the reference whiteboard data stored in the IFO 35, and image processing and output appropriate image data to the plotter unit 36.

The power supply section 41 (see FIG. 2) of the apparatus of the embodiment is roughly composed of two types of systems. One is a power supply system Vcnst that is turned on / off only by the main power supply SW, and the other is a power supply system Vtemp whose output is cut off by an external control signal Voff. External control signal Vof
Elements that generate f include an open / close sensor 40a, a document sensor 40b, and a power return SW 40c. Open / close sensor 40
a is a pressure plate for holding the document (not shown in FIG. 1)
Alternatively, it is a sensor that detects opening and closing of the ADF 2 that automatically supplies a document, and the document sensor 40 b is a sensor that detects that a document is set on the ADF 2. Although not shown in FIG. 1, a standby state (a state in which the main power supply is not used and a predetermined time has elapsed after the main power is turned on) is displayed on an operation panel for setting various machine conditions and receiving an input such as a start of reading. (Some power supply is stopped and waiting for return command)
A power recovery SW 40c for instructing power recovery from the power supply is provided. FIG. 3 is a block diagram showing the configuration of the power supply unit and its control circuit according to the embodiment of the present invention in more detail. 2
One of the power supply systems Vcnst (steady 5V) is
This is a power supply system that is output when the main power supply SW is turned on. In this embodiment, the power supply system uses the open / close sensor 40a, the document sensor 40b, the power return SW 40c,
CPU 29 and the output of each sensor and SW
9 are supplied to the elements required for transmission. on the other hand,
Another power supply system Vtemp (24 V, 12 V, 5
V) is a power supply system whose output is turned off by a Voff signal sent from the CPU 29 when the image reading device is not operated for an arbitrary time even when the main power supply SW is turned on. In this embodiment, this power supply system The power is supplied to the control unit 29c that controls the power supply unit 41, the scanner unit 51, and the plotter unit 52.

Next, the operation procedure of the reference level adjustment and the gain adjustment performed when the main power is turned on and when the image reading apparatus returns from the standby (power saving) state will be described. FIG. 7 is a flowchart showing one embodiment of the operation procedure of the reference level adjustment and the gain adjustment. Referring to FIG. 7, after turning on the main power supply SW, first, the power supply unit 41 turns on the power supply Vcnst and the power supply Vtemp to supply power to each unit of the apparatus (S1). CP
Here, U29 performs the initial setting of the image reading apparatus (S29).
2). The initial setting mainly includes the following settings. -Timing setting of various pulses for driving the CCD 21. -Timing setting of the sampling pulse of the sampling circuit 23.・ Initial gain setting of the gain amplifier 24. -Initial offset setting of the offset adjustment circuit 25. Next, the lamp 4 is turned on and the carriage is homed to determine the home position of the traveling body 12, and the traveling body 1 is moved to the home position (S3).

Next, reference level E / O difference adjustment is performed (S
4). In this adjustment, when the output of the CCD 21 is of two systems, the reference level between even and odd when the processing system is divided into even (odd) and odd (odd) pixels for processing is adjusted to have the same value. Things. even,
Each reference level of odd is detected by a black level detection circuit 27, and an offset adjustment amount is calculated by the CPU 29 based on a difference value of the reference level between even and odd, and D / A
The adjustment amount Veo to the offset adjustment circuit 25 is set via the converter 32 (the initial value is reset). Thereafter, the reference level is adjusted to a predetermined value (S
5). In this reference level adjustment, similarly to the reference level E / O difference adjustment in S4, the detection value of the black level detection circuit 27 is used.
The offset adjustment amount is calculated by the CPU 29 so that the detection value becomes a predetermined value, and the adjustment amount Vos to the offset adjustment circuit 25 is set via the D / A converter 33. The value of the predetermined reference level in S5 is generally a value that does not interrupt 0 even if there is an influence of noise, in consideration of performing black level subtraction later. Next, light from the reference white plate 11 is reflected by the CCD 21 as reflected light detected by the CCD 21 in order to adjust the gain.
The traveling bodies 12 and 13 are moved so as to be incident on the reference numeral 21 (S7), and the reference white plate 11 is read. The gain adjustment is performed so that the output value when the reference white plate 11 is read, that is, the detection value of the white peak detection circuit 30 becomes a predetermined value.
The adjustment amount Vg to the gain amplifier 24 is set by resetting the initial value. As for the value of the gain to be adjusted, the higher the output value of the A / D converter 26 does not overflow even if the fluctuation factors such as the amount of light of the lamp 4 are considered, the higher performance of the A / D converter 26 can be obtained. . Thereafter, the CPU 29 stores the values set as the reference level adjustment value and the gain adjustment value in the storage unit (S8).

After saving the set values, the lamp 4 is turned off and the traveling body is moved to the home position in preparation for reading the original (S9). Thereafter, when the image reading apparatus is not used for a predetermined time, the CPU 29 enables the Voff signal transmitted to the power supply unit 41 to cut off the output of the power supply Vtemp in the on state. As a result, the power supply to the above-described portions of the apparatus, such as the plotter and the scanner unit, is turned off, and the power consumed by the apparatus is significantly reduced, and the apparatus enters a power saving state. As a flow, the elapse of a predetermined time is checked (S10), the elapse of the predetermined time is confirmed, the power supply Vtemp is turned off, and a standby (power saving) state is set (S12). If the reading instruction is given before the elapse of the predetermined time, the reading is started. As a flow, the elapse of a predetermined time is checked (S10). If not, it is checked whether or not there is a reading start instruction (S11). If there is an instruction, reading is started. If there is no instruction, the process returns to S10. In the standby state, an open / close sensor 40a that opens and closes when a copy original is placed on the contact glass, or an original sensor 40b that detects that an original has been set on the ADF 2, and a power return switch SW4
0c is supplied with a power supply Vcnst, so that the CPU 29 can recognize the state of the sensor and SW. The return from the standby state is performed when the sensor and the SW output change, and the CPU 29 operates the Voff signal,
Vtemp of the power supply unit 41 is turned on, and power is supplied to each unit of the apparatus. As the flow, the open / close sensor, power return S
After confirming that the output such as W has changed (S13),
Vtemp of the power supply unit 41 is turned on (S13).

The reading operation starts when Vtemp is turned on. In this embodiment, the same adjustment operation (S4 to S7) as performed when the main power is turned on is not performed in all cases when returning from the standby state. Thus, the return time is shortened. Therefore, using the gain and offset set values (set values obtained in S5 and S7 when the main power is turned on) stored in the storage unit in S8, the values are set in the gain amplifier 24 and the offset adjustment circuit 25 (S15). . Next, the lamp 4 is turned on, and the traveling body 1 is turned on.
2, 13 were moved to the home position (S16)
Thereafter, reading is performed to detect the reference level, and the reference level value is detected by the black level detection circuit 27 (S1).
7). The CPU 29 determines whether or not the detected reference level value is within the allowable value (S18). If the detected reference level value is not within the allowable value, the reference level adjustment starting from S4 is performed again as in the case of turning on the main power supply SW. On the other hand, if the detected reference level value is within the allowable value, the traveling bodies 12 and 13 are moved to the position of the reference white plate 11 (S19), read for detecting the white peak value, and read the white peak detection circuit. The value is detected by 30 (S20). The CPU 29 determines whether or not the detected white peak value is within the allowable value (S29).
21) If not within the allowable value, the reference level adjustment starting from S4 is performed again in the same manner as when the main power switch is turned on.
If it is within the allowable value in S21, the process returns to S9, turns off the lamp, stands by at the home position, and waits for reception of a reading start signal.

Next, another embodiment of the operation procedure of the reference level adjustment and the gain adjustment performed when the main power is turned on and when the image reading apparatus returns from the standby (power saving) state will be described below. FIG. 8 is a flowchart showing the operation procedure of the reference level adjustment and the gain adjustment according to the present embodiment. This embodiment is different from the above-described embodiment in the operation procedure performed when returning from the standby state.
The operation of the / O difference adjustment, the reference level adjustment, and the gain adjustment, and the saved gain and offset set values (set values obtained when the main power is turned on) are used at the time of restoration. That is, S1 to S16 of FIG.
Steps S101 to S11 in FIG.
This is the same as step 6. Therefore, S101 to S101 in FIG.
The above description will be referred to without duplicating the description of step S116. As shown in the flow chart of FIG. 8, after entering the standby state in S112, when returning from the standby state, the gain and offset set values obtained and saved when the main power supply is turned on are set (S11).
5) The reference level is detected based on the set value (S).
117). At this time, in the previous embodiment, it is checked whether the detected reference level is within the allowable value, and whether the white peak value obtained from the detected whiteboard data is within the allowable value. If not,
Adjustment items when main power is on (reference level E / O difference adjustment,
All adjustments (reference level adjustment and gain adjustment) are performed.

However, in the present embodiment, it is determined whether or not each of the adjustment items falls within the allowable value. As a result, if the value does not fall within the allowable value, the adjustment item is individually re-adjusted. Items that fall within the values are not readjusted. By doing so, the time required for adjustment can be reduced. In the flow of FIG.
Based on the reference level value detected in S117, it is first checked whether or not the reference level E / O difference value is within the allowable value (S118).
The O difference adjustment is performed again (S119). On the other hand, if it is set, the reference level E / O difference adjustment is passed, and the set value (the stored data obtained when the main power is turned on) is used as it is. Next, in S117, the black level detection circuit 27
It is checked whether or not the reference level value is within the allowable value from the reference level values detected by (1) (S120).
If not, adjust the reference level again (S1
21). On the other hand, if it is set, the reference level adjustment is passed, and the set value (the stored data obtained when the main power is turned on) is used as it is. After this, the traveling body 1
2, 13 are moved to the position of the reference white plate 11 (S122),
Reading is performed to detect a white peak value, and the value is detected by the white peak detection circuit 30 (S123). next,
It is checked whether or not the white peak value detected by the white detection detection circuit 30 is within the allowable value (S124). If not, the gain adjustment is performed again (S125).
On the other hand, if it is set, it passes the gain adjustment and the set value (the data obtained when the main power was turned on that was saved)
Use as is. Then, the process returns to step S109, where the lamp is turned off, the apparatus stands by at the home position, and waits for a read start signal.

[0021]

(1) Effects corresponding to the first aspect of the present invention When returning from a standby state in which a part of power supply is stopped to a state in which reading can be executed, the main power is turned on as a set value to the image signal processing means. The adjustment is performed at the time, the stored set value is set, and it is determined whether or not the characteristic of the image signal processing means is within a predetermined appropriate range based on the processing result of the obtained image signal. When it is determined that the value is within the proper range, the reading is executed using the set value as it is, so that the adjustment which was always performed at the time of the return can be omitted, so that the return time can be reduced. It does not take longer than necessary, and the waiting time of the user can be reduced.

(2) Effects corresponding to the second aspect of the invention In addition to the effects of the above (1), when it is determined that the characteristics of the image signal processing means when returning from the standby state are not within the proper range. During the standby state, the lamp,
Even when the reference white plate or the like is replaced, the characteristics according to the change of the condition can be set, so that stable read image data can be obtained. (3) Effects corresponding to the third aspect of the invention In addition to the effects of the above (2), when it is determined that any of the characteristics of the image signal processing means to be adjusted does not fall within the proper range, By performing the adjustment performed when the power is turned on, more excellent read image data can be obtained. (4) Effects corresponding to the fourth aspect of the invention In addition to the effects of the above (2), readjustment is performed only for the characteristics of the image signal processing means to be adjusted that are determined not to be within the proper range. By performing the adjustment, that is, performing the minimum necessary readjustment, the time required for the adjustment can be further shortened as compared with the invention of claim 3. (5) Advantages Corresponding to the Invention of Claim 5 The advantages of (1) to (4) above can be obtained in an image processing apparatus such as a copying machine, a facsimile, a scanner, the above-mentioned multifunction machine, or a filing apparatus for storing image data. This makes it possible to speed up the processing of the image processing apparatus and improve the performance.

[Brief description of the drawings]

FIG. 1 shows a schematic configuration of an image reading apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic block diagram of an image reading circuit according to an embodiment of the present invention.

FIG. 3 is a block diagram showing the configuration of a power supply unit and its control circuit according to an embodiment of the present invention in more detail.

FIG. 4 is a graph showing characteristics of a gain amplifier, showing a relationship between a gain control amount (Vg) and a gain.

FIG. 5 is a graph showing characteristics of an offset adjustment circuit;
The relationship between the offset control amount (Veo, Vos) and the offset amount is shown.

FIG. 6 is an example of a timing chart showing a relationship between signals related to reference level adjustment and gain adjustment.

FIG. 7 is a flowchart showing an embodiment of an operation procedure of a reference level adjustment and a gain adjustment performed at the time of turning on a main power supply and at the time of returning from a standby state.

FIG. 8 is a flowchart illustrating another example of the operation procedure of the reference level adjustment and the gain adjustment performed when the main power is turned on and when the apparatus returns from the standby state.

[Explanation of symbols]

9: sensor board unit, 10: image processing unit, 2
1 ... CCD, 24 ... Gain amplifier,
25: offset adjustment circuit, 26: A / D converter, 27: black level detection circuit, 28: black level subtraction circuit, 29: CPU, 30 ...
White peak detection circuit, 31, 32, 33 ... D / A converter, 34 ... shading correction circuit, 35 ... shading data FIFO, 36 ... image processing, plotter section,
40a: open / close sensor, 40b: original sensor,
40c: power return switch, 41: power supply unit,
51: scanner unit, 52: plotter unit.

Continued on the front page F-term (reference) UA13 XA01

Claims (5)

[Claims] An image reading means, an image signal processing means for performing a process according to a set value to an image signal read by the image reading means, and a characteristic of the image signal processing means by changing a set value of the image signal processing means. Means to adjust the
Setting value storage means for storing the setting values of the image signal processing means,
In an image reading apparatus provided with power control means for shifting from a power supply state at the time of turning on the main power supply to a power supply stop state in which a part of power supply is stopped and then canceling the power supply stop state when returning, an image signal adjusted at the time of turning on the main power supply The set value of the processing means is stored in the set value storage means, and when the power supply stop state is released by the power supply control means, the set value stored in the set value storage means is set in the image signal processing means, and the obtained image signal is obtained. A means for determining whether or not the characteristics of the image signal processing means are within a predetermined appropriate range according to the processing result, and when it is determined that the characteristics of the image signal processing means are within the appropriate range,
An image reading apparatus wherein an image reading is executed by using a set value as it is. 2. The image reading device according to claim 1, wherein when it is determined that the characteristic of the image signal processing unit at the time of canceling the power supply stop state is not within an appropriate range, the characteristic of the image signal processing unit is adjusted. An image reading device, wherein readjustment is performed by means for performing the reading. 3. The image reading device according to claim 2, wherein when it is determined that any of the characteristics of the image signal processing means to be adjusted is not within an appropriate range, the adjustment is performed when the main power is turned on. An image reading apparatus, comprising: 4. The image reading apparatus according to claim 2, wherein the adjustment is performed only for the characteristics determined to be out of the proper range among the characteristics of the image signal processing means to be adjusted. Image reading device. 5. An image processing apparatus comprising the image reading apparatus according to claim 1.