JPH04358465A - Image input device - Google Patents

Abstract

PURPOSE:To reduce the total power consumption of an image input device by intermittently turning on a light source which irradiates an original screen in accordance with the scanning value. CONSTITUTION:An encoder 1 outputs a synchronizing signal synchronous with the manual scan of a sensor unit 3 at the time of scanning the unit 3. An LED array 2 includes plural LEDs of high luminance set side by side. The unit 3 inputs the reflected light caused at a part of the array 2 irradiated by the light to the image formed on an object (original) to be read and then outputs an image signal VD. A control circuit 13 turns on the array 2 at each time interval and in response to the push of a read key arranged on a key board 33 according to the interruption signal obtained by a timer 18. A timer 19 starts a clock in response to the interruption signal received from the encoder 1 to store the signal VD in a RAM 29 and also turns off the array 2 after storage of a prescribed amount of image data.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image input device that reads and inputs an image of a document by manually or automatically scanning a photoelectric conversion element or the like.

0002

2. Description of the Related Art In conventional character recognition devices that read character images, the reading surface of the image can be changed by pressing a reading start button, as illustrated and explained in, for example, Japanese Patent Publication No. 63-76566. The LED array for irradiation is lit continuously. Then, the speed of manual scanning is detected by an encoder equipped with a roller or the like that rotates in synchronization with manual scanning, and the sensor accumulates charges of light reflected from the original image for a certain period of time in accordance with the detected speed. Then, the electric charge accumulated in the sensor was extracted serially, and the extracted data was captured as image data on the object to be read.

0003

[Problems to be Solved by the Invention] However, in the conventional example described above, for example, in a portable reading device, the LED array is lit by a battery used as a power source, so if the LED array is lit continuously, The drawback was that the battery was significantly consumed.

The present invention has been made in view of the above-mentioned conventional example, and provides an image input device in which the power consumption of the entire device is reduced by intermittently driving a light source that illuminates the image surface of a document. The purpose is to

[0005]

Means for Solving the Problems In order to achieve the above object, an image input device of the present invention has the following configuration. That is, it is an image input device that photoelectrically reads and inputs two-dimensional image information, and includes an irradiation device that irradiates light onto an image information surface, and a device that scans the image information surface and irradiates it with light by the irradiation device. a photoelectric conversion means for inputting and photoelectrically converting reflected light from the photoelectric conversion means; a storage means for accumulating output data from the photoelectric conversion means; a detection means for detecting the scanning amount of the photoelectric conversion means; The irradiation means is turned on in accordance with the detected scanning amount, and the image data from the photoelectric conversion means is stored in the storage means. After storing a predetermined amount of image data in the storage means, the irradiation means and control means for controlling the light to turn off.

[0006]

[Operation] In the above configuration, when the image information surface is scanned and the reflected light of the light irradiated by the irradiation means that irradiates the image information surface is input and photoelectrically converted, the scanning amount of the photoelectric conversion means The irradiation means is turned on in accordance with the scanning amount detected by the detection means that detects the image data, and the image data from the photoelectric conversion means is stored in the storage means.After storing a predetermined amount of image data in the storage means, It operates to turn off the irradiation means.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of a manual reading device according to a first embodiment of the present invention, which is equipped with a recognition function that reads an image by manual scanning, performs character recognition, and displays the meaning of the word as the recognition result. This figure shows the general structure of an electronic dictionary.

In the figure, reference numeral 1 denotes an encoder, which includes a roller or the like that rotates in synchronization with the scanning of the sensor unit 3 by manual scanning.The rotation of the roller is detected by a photointerrupter, and the manual scanning is performed by detecting the rotation of the roller. Outputs a synchronization signal synchronized with. 2 is an LED array, which is composed of a plurality of high-brightness light emitting diodes arranged side by side. 3 is a line sensor unit that applies L to the image on the object to be read (original).
Input the reflected light from the part of the ED array 2 that is hit by the light,
The signal is converted into an electrical signal, and this read signal is voltage amplified and serially output.

To explain the configuration of this line sensor unit 3, numeral 4 is a photoelectric conversion element, and the intensity of the received light is determined, that is, the white pixel part has a strong brightness, and the black pixel part has a weak brightness, and the reflected light is reflected. It has a plurality of cells that accumulate for a certain period of time and store a high potential for white pixels and a low potential for black pixels. 5 is a shift register, and photoelectric conversion element 4
The potentials of each cell accumulated in the cell are input in parallel, shifted one cell at a time in series, and transferred in sequence. An amplifier 6 amplifies the output from the shift register 5. 7
is an output buffer, which amplifies the current of the analog signal amplified by the amplifier 6 in order to output it to an external circuit. A comparator 8 compares the threshold signal 41 for binarization determined by the threshold circuit 9, which is an external circuit, with the analog signal amplified by the amplifier 6, and converts the analog image signal into a binary image signal. is converting.

9 is a threshold circuit, which connects the line sensor unit 3.
Based on the input analog signal, the threshold level for binarizing the analog image signal is determined and the threshold signal 4 is determined.
1 is output. This threshold signal 41 outputs a threshold signal 41 of an intermediate potential such that a high potential among analog signals corresponds to a white pixel and a low potential corresponds to a black pixel. 10 is a flip-flop that divides the frequency of φCLK, which is the transfer clock of the shift register 5, by 2; 11 inputs the pulse signal from the flip-flop 10 whose frequency has been divided by 2;
This is a flip-flop that stores odd-numbered pixel data (binary level) of the binary image signal VD. 12 is an OR gate which takes the logical sum of the odd numbered pixels from the flip-flop 11 and the even numbered pixel data of the binarized image signal output VD from the comparator 8 and outputs the result.

Reference numeral 13 denotes a large-scale integrated circuit (LSI) including an interrupt input port, an interrupt control circuit, a clock pulse generator, an instruction decoder, a timer group, a register group, an ALU input port, an output port, and an image input shift register, which will be described later.
), etc., and is a central control circuit that executes and processes using a microprogram method. The configuration of this control circuit 13 will be explained in detail below.

A clock pulse generator (CPG) 14 generates a pulse signal of a constant period based on the delay time of the crystal oscillator 15, generates a basic clock signal for internal arithmetic processing, and also generates a transfer clock for the shift register 5. The φCLK signal is generated. An interrupt input port 16 receives a signal synchronized with manual scanning from the encoder 1 and outputs it to the interrupt control circuit 17. This results in
The interrupt control circuit 17 temporarily suspends the procedure of the microprogram being executed, and controls a microprogram group that executes interrupt processing in response to the interrupt by the encoder 1, that is, the LED.
The contents of the address register are changed to the address of the microprogram that executes lighting of the array 2, input processing of image data, etc.

A timer 18 measures time and outputs an interrupt signal to the interrupt control circuit 17 after a certain period of time.
In response to an interrupt signal from the timer 22, a process of lighting up the LED array 2 at regular intervals in response to a press of a read key provided on a keyboard 33, which will be described later, is executed. A timer 19 also has the same function as the timer 18, and measures time and outputs an interrupt signal after a certain period of time. This timer 19 starts measuring time in response to an interrupt signal from the encoder 1 received at the interrupt input port 16, and receives an image signal from the output VD from the sensor unit 3 by interrupting the timer 19 after a certain period of time. , executes processing for storing in the RAM 29 and processing for turning off the LED, which will be described later. At the same time, when there is an interruption from the encoder 1 while the timer 19 is counting, it is detected and a process is executed to store in the RAM 29, which will be described later, that the scanning speed of the device by manual scanning is too fast.

20 is an R disposed outside the control circuit 13.
When sequentially calling and executing microprograms stored in the OM 29, the instruction decoder receives and decodes the microprograms and outputs signals for controlling each register, control unit, etc. Reference numeral 21 denotes an internal bus line through which data is transferred to various registers in response to control signals from the instruction decoder 20, and through which data is passed during arithmetic processing. Furthermore, when a branch instruction, which is one of the microprogram instructions, a destination address is transferred, and when an interrupt occurs, address data called as an interrupt address is transferred. 22 is an A register, which is used as a general-purpose register during various microprogram instructions. Also, 2
3 is an arithmetic unit (ALU) which executes addition and subtraction when arithmetic instructions of various microprograms are issued. Reference numeral 24 denotes an index (X) register, which is used to indirectly specify the location of a storage section allocated to each address of the RAM 29, which will be described later. Reference numeral 25 denotes an image input shift register which inputs the output signal from the OR gate 12 which calculates the logical sum of the image signal output VD mentioned above, shifts it and outputs it. 26 is an input port into which key signals from the keyboard 33 are input. 27 is an output port, which outputs a key scan signal to the keyboard 33,
Further, the charge accumulated in the photoelectric conversion element 4 is outputted in parallel to the shift register 5, and a signal φTR for clearing the accumulated charge is outputted.

An external bus line 28 includes an external address bus and an external data bus line. 29 is a random access memory (RAM) having a writeable and readable storage section allocated for each address. This RAM 29 includes a buffer memory for storing data,
It includes a flag for storing judgment results, a counter for storing count values, and a register section for temporarily storing various data. Reference numeral 30 denotes a ROM, which stores microprograms that subdivide various processing procedures and execute them sequentially, a recognition dictionary, an English-Japanese dictionary, etc. in code. 31 is a display control circuit which receives the processing result from the bus line 28, converts it into a signal level for display on the display 32, and outputs it. 32 is the aforementioned CPU 13, ROM 30,
This is a display device that displays the results processed by the RAM 29. A keyboard 33 includes a read key for instructing the start of a reading scan. 34 is a power supply circuit for supplying power to each of the above-mentioned parts.

In the above configuration, the processing flow when the read key on the keyboard 33 is pressed to instruct the start of reading scanning is shown in the flowcharts of FIGS. 3 and 4, and when the line sensor unit 3 is manually scanned. The flow of interrupt processing based on the output signal from encoder 1 is shown in FIG. 5, the flow of interrupt processing by timer 18 is shown in FIG. 6, and the flow of interrupt processing by timer 19 is shown in the flowchart of FIG.

First, the flow of processing when the read key is pressed will be explained with reference to the flowcharts of FIGS. 3 and 4.

When the read key is pressed, the process advances to step S1, and the interrupt control circuit 17 is controlled to permit an interrupt from the encoder 1. Next, the process proceeds to step S2, where the timer 18 starts measuring time, and the TM is a counter for controlling the LED array 2 to light up at regular intervals.
Clear AC to “0”. This counter TMAC is
It is provided in RAM29. Next, the process proceeds to step S3, where the counter UCNT used when capturing the image signal and storing it in a specific address location of the RAM 29 is cleared to "0", or the counter INT2C, which counts the number of receptions of the encoder 1, is cleared to "0". clear. Next, the process proceeds to step S4, where counters ERRC1 to E are counted up when the period of the signal from encoder 1 is too fast.
Clear up to RRC10 to “0”, then ERRC1~
A counter EPTR that specifies which one of the ERRC10 is to be counted up is set to "1". Further, as a result of cutting out the scanned image as a word, the flag FCHA, which becomes "1" when one word is cut out, is set to "0". Furthermore, the flag FERR, which becomes "1" when the encoder 1 is too early, is set to "0". These counters, flags, etc. mentioned above are provided in the RAM 29.

[0020] Steps S5 to S7 show a process of determining whether or not the reading scan started by the read key has been completed, and in step S5, the flag F is
It is determined whether CHA is "1" or not, and it is determined whether one word has been extracted. Here, if it is determined that one word has been cut out (FCHA=1), the processing from step S8 onwards is executed. Further, in step S6, it is determined whether the designated position of the RAM 29 for storing the image signal is full, and a counter U for counting the storage position is determined.
When detecting that the CNT value is 640 or more,
It is determined that the process has ended, and the processes from step S8 onwards are executed.

When the read key is pressed in step S7, the process proceeds to step S16, where the counter UCNT for counting the storage position of the image signal is compared with the counter DEVC for counting the end portion of the character cutting process. If it is, all of the captured images have been subjected to character cutting processing, and the process returns to step S5.

On the other hand, counter UCNT and counter DEV
If C does not match, this indicates that there is a portion of the captured image that has not been subjected to the character cutting process, so the process advances to step S17 and the subsequent processes are executed. In step S17, the outline of the character is traced, and when the outline tracing is completed, 1
Character cutting processing is performed based on an algorithm that determines that one character has been cut out. Next, the process proceeds to step S18, where the spaces between characters are compared, and when an extremely wide space occurs, a word cutting process is performed in which it is determined that the space between words has reached. In step S19, it is checked whether word extraction has been completed, and if it has been completed, the process proceeds to step S24, but if it has not been completed, the process proceeds to step S20.

Steps S20 to S23 are processes for setting an error flag, FERR, if the scanning speed of manual scanning of the device is too fast. Step S20 counts the number of premature errors.
A counter group consisting of book counters (ERRC1 to E
The value of the pointer EPTR that specifies the position of RRC10) is the counter DE that counts the end of character cutting processing.
This is a process of determining whether the value of VC is smaller than the value divided by "64". That is, the premature error counter group ERR
If the determination of C is necessary, the process proceeds to step S21, but if the determination has already been performed, the process returns to step S5.

In step S21, the pointer EPTR is updated, and a value obtained by dividing the counter DEVC, which counts the end of character cutting processing, by "64" is set in the pointer EPTR. Next, the process advances to step S22, and it is determined whether the error counter pointed to by the pointer EPTR of the premature error counter group ERRC is smaller than a predetermined value "4". On the other hand, in step S22,
When the value of the pointer EPTR is smaller than "4", it indicates that the device's manual scanning speed is sufficient for character cutting and character recognition; when it is larger than "4", the device's manual This indicates that the scanning speed is too fast. Therefore, when the scanning speed is too fast, the process advances to step S23 and the too fast error flag FERR is set.
Set to “1”. Next, the process proceeds to step S24, where a flag FCHA indicating the end of word extraction is set to "1".

What is important here is that after the word extraction is completed, the processing for detecting that the scanning speed in steps S20 to S23 is too fast is not performed. Therefore,
Even if the value of the counter group ERRC that counts the number of premature errors is a large value of "4" or more after word extraction is completed, the premature flush flag FERR should not be set to "1".

After repeating the processing loop of steps S5 to S24 to perform character cutting and word cutting, if the loop is exited under one of the conditions of steps S5 to S7, the image signal is stored in step S8. The value of the counter UCNT that counts the position is a predetermined value "
5". This is because the user may repeatedly press and release the read key when manually scanning or positioning the sensor unit 3. If a long processing routine such as recognition processing is executed every time the read key is pressed again, the manual scanning distance becomes considerably long, and as a result, the image read by sensor 3 can only be captured from the middle. Therefore, in step S8, in order to solve this problem, when the value of the counter UCNT is "5" or less and scanning is hardly performed, nothing is done. Therefore, even if the read key is pressed again next time, the read key process can be executed immediately and the image can be captured from the beginning.

[0027] In step S8, the value of the counter UCNT is "
5" or more, the process advances to step S9, and it is determined whether or not the premature error flag FERR is on. If it is on, that is, "1", the process advances to step S10,
A message "Please pull slowly" is displayed on the display 32 in the case of a premature error. On the other hand, if this error flag FERR is "0", step S11
Then, processing such as recognition processing and English-Japanese dictionary search is performed.

In step S11, the characteristics of each character that has been subjected to the character cutting process are extracted and compared with the character recognition dictionary portion in the ROM 30, and recognition processing is performed to select the character with the most similar characteristics as the recognized character. Next, the process proceeds to step S12, and as a result of the recognition, it is determined whether or not there is an optimal character. If character recognition is not possible, the process proceeds to step S15, and it is determined that a disordered image was captured during manual scanning. , a message asking you to re-enter "Please re-enter"
Display. On the other hand, if character recognition is successful, step S
Proceed to step 13 and save the word that is the recognized character string to the ROM30.
Search within the English-Japanese dictionary section and select matching words. Then, in step S14, information such as the meaning of the word is displayed on the display 32.

FIG. 5 is a flow chart showing the flow of interrupt processing based on the output signal from the encoder 1 when the line sensor 3 is manually scanned.

First, in step S31, a counter INT2C for counting the number of interrupts by the encoder 1 is incremented. Next, in step S32, the counter IN
It is determined whether T2C is smaller than a predetermined value "5", and if it is smaller, the process is terminated without doing anything and the process returns to the main routine. In step S33, counter INT2
It is determined whether the value of C is equal to "5", and if it is equal to "5", the process proceeds to step S39, where the timer 18 is stopped and the LED array 2 is turned off. This timer 18 starts counting when the read key is pressed, and in order to let the user know that the read key has been pressed, the LE
It is used to execute the process of dynamically lighting up the D array 2. Details of this process will be described later with reference to the flowchart in FIG. Note that in this step S39, the timer 18 is prohibited from measuring time if the value of INT2C is "5".
This is because when it is larger than , scanning of the line sensor 3 has started, and the timer 19 lights up the LED array 2 for image capture.

[0031] In step S33, the value of INT2C is "5".
”, the process proceeds to step S34, where it is determined whether the LED array 2 is lit. This means that if the scanning of the line sensor 3 is fast, the LED array 2 is lit for a predetermined accumulation time This is because an encoder interrupt may occur during the time, and if the LED array 2 is lit, the process advances to steps S37 and S38.Here,
Since the encoder interrupt was too early, in order to increment the position specified by the counter group ERRC that counts premature errors, first, in step S37, every time an image signal is stored, it is incremented by 1 and the storage position is counted. Divide the value of the counter UCNT by "64", set the integer part in the index register 24, and then proceed to step S.
At step 38, the ERRC position pointed to by the index register 24 is incremented by one. As mentioned in the explanation of the flowcharts of FIGS. 3 and 4, using the counter group ERRC incremented in step S38,
Premature error processing is executed in the read key processing of FIGS. 3 and 4.

On the other hand, if it is determined in step S34 that the LED array 2 is not lit and the accumulation time has elapsed, the process proceeds to step S35.
Then proceed to process to import the next image data. That is, in order to turn on the LED array 2 for a predetermined accumulation time, time measurement by the timer 19 is started in step S35, and then, in step S36, the LED array 2 is turned on. As a result, after the predetermined accumulation time, timer 1
9 completes the count and generates an interrupt, and the image capturing process and the LED array 2 extinguishing process shown in FIG. 7 are performed.

FIG. 6 is a flowchart showing interrupt processing by the timer 18. After the read key is pressed, the LED array 2 is dynamically turned on at a duty of 1/8,
It shows processing for notifying the user that the read key has been pressed.

In FIG. 6, first, in step S51, a counter TMAC for counting the number of occurrences of the timer 18 is incremented (+1). Next, in step S52,
Determine whether the value of counter TMAC is “7” and set it to “7”
If so, the process advances to step S55, where the LED array 2 is turned on and the counter TMAC is cleared to "0".

If the value of the counter TMAC is not "7" in step S52, the process advances to step S53, and the counter TMAC is
It is determined whether the value of MAC is "0", and if it is "0", the process advances to step S54, and the LED array 2 is turned off.

Through the above processing, the counter TMAC is counted from 0 to 7 every time an interrupt occurs by the timer 18, and when the value of TMAC changes from "7" to "0", the LED array 2 is turned on. be able to. In this way, the LED array 2 can be lit with a duty ratio of 1/8.

FIG. 7 is a flowchart showing the flow of interrupt processing generated by the timer 19. In this process, in step S35 of the encoder interrupt process in FIG. 5 due to manual scanning of the line sensor 3, the timer 19 starts measuring a predetermined time, and after the predetermined time, an interrupt , and performs processing such as capturing an image and turning off the LED array 2.

First, in step S61, a counter UCNT that counts the storage positions of image signals is incremented. Next, in step S62, the counter UCNT
A counter DT serves as a pointer for storing the captured image in the image storage location in the RAM 29.
Clear PTR to “0”. Next, in steps S63 and S64, the output line φTR from the output port 27 is changed from "1" to "0" to output the charges accumulated in the photoelectric conversion element 4 to the shift register 5 in parallel. As a result, the read image data is transferred and stored in the shift register 25, shifted by the next shift clock φCLK, and outputted in serial.

Steps S65 to S82 show the flow of processing for storing data from the image input shift register 25 (hereinafter referred to as IMG/SR) to the image buffer, which is an image storage location in the RAM 29. First, in step S65, serial input is permitted, and the image serially shifted from the shift register 5 to the IMGSR 25 is stored in the A register 22 in step S66.

Here, the counter UCNT counts the image signal storage position in the main scanning direction, that is, the manual scanning direction, and the counter DTPTR counts the horizontal scanning direction,
That is, the shift register 5 counts the number of bytes stored at one time. Here, since the capacity of the shift register 5 is 9 bytes, when DTPTR counts 9 times, one column of image data is taken in. This corresponds to one counter UCNT. As a result, in step S67, the counter UCNT
By multiplying the value of RA by 9 times, adding the value of DTPTR to it, and setting it in the index register 24, RA
The address of the image buffer where the M29 image is stored can be set.

When the address to be stored in the RAM 29 is thus determined, the process advances to step S68, and the image stored in the A register 22 is stored in the image buffer at the address pointed to by the index register 24. At the same time, the counter DTPTR in the sub-scanning direction is incremented in order to capture the next 1 byte of image data. Next, the process advances to step S69, and it is determined whether or not the capture of one row of images has been completed, based on whether the value of DTPTR is "9". In step S69, counter D
If the value of TPTR is not "9", it means that the image capture of one row has not been completed, and therefore the process proceeds to step S65.
Return to and repeat the process described above. And step S
If the value of DTPTR is "9" in step S69, it is assumed that one row of image capture has been completed, and the process advances to step S70.
Turn off the ED array 2.

Steps S71 to S73 increment one of the counters ERRC that counts premature errors when an interrupt (INT2) by the encoder 1 occurs by moving by manual scanning during processing of an interrupt by the timer 19. This shows the process flow. First, in step S71, it is determined whether or not it is an INT2 interrupt, and if it is not an INT2 interrupt, the interrupt processing by the timer 19 is ended.

On the other hand, if there is an interrupt by INT2, the process advances to step S72, where the counter UCNT counting the storage position of the image signal is divided by "64" and the integer part is stored in the index register 24. Then, in step S73, one of the counters ERRC pointed to by the index register 24 is incremented.

As described above, according to this embodiment, FIG.
Through the interrupt processing by the encoder 1 shown in FIG. 7 and the interrupt processing by the timer 19 shown in FIG. 7, one of the positions designated by the counter group ERRC for counting premature errors can be incremented. As a result, counter group E
In the read key processing routine shown in FIGS. 3 and 4 using RRC, the premature error flag FERR can be set. Note that, as shown in FIG. 4, the premature error flag FERR is not set in step S23 after word extraction is completed in step S19. As a result, even if there is a skipped part, as shown by 91 in FIG. 9, for example, after the necessary image capture is completed, that is, after the word extraction is completed, an error state does not occur too soon.

<Other Embodiments (FIG. 8)> FIG. 8 is a block diagram showing a schematic configuration of an image input device in a second embodiment of the present invention. Note that the description of the same parts as those of the image input device of the first embodiment shown in FIG. 1 described above will be omitted.

In this embodiment, the four outputs of the output port 27 inside the control circuit 13 are used to rotate the stepping motor 87, and although not shown, the LED array 2 and the line image sensor 3 are driven. Scan the loaded carriage. In this case, in response to the movement of the carriage due to the relatively slow rotation of the stepping motor 87, the LE
The D array 2 is turned on and the timer 19 starts measuring time. As a result, an interrupt is generated by the timer 19 every time the timer 19 measures a predetermined time. In synchronization with this interrupt timing, the control circuit 13 stores the image data stored in the sensor 3 in the RAM 29, and turns off the LED array 2. By repeating such operations, the LED array 2 can be turned on/off intermittently.

The present invention may be applied to a system made up of a plurality of devices, or to a device made up of one device. It goes without saying that the present invention can also be applied to cases where the present invention is achieved by supplying a system or device with a program that executes the processing defined by the present invention.

As explained above, according to this embodiment, by controlling the lighting/extinguishing of the LED array 2 every time a predetermined time is counted by the timer, intermittent lighting control of the LED array is possible. This has the effect of reducing battery consumption without increasing costs.

[0049]

As described above, according to the present invention, the power consumption of the entire apparatus can be reduced by intermittently driving the light source that illuminates the image surface of the document.

[Brief explanation of the drawing]

[Figure 1]

FIG. 2 is a block diagram showing a schematic configuration of an image input device of this embodiment.

[Figure 3]

FIG. 4 is a flowchart showing processing when a read key of the image input device of the present embodiment is pressed.

FIG. 5 is a flowchart showing an interrupt process that occurs when the encoder rotates in the image input device of this embodiment.

FIG. 6 is a flowchart showing interrupt processing by the timer 18 in the image input device of this embodiment.

FIG. 7 is a flowchart showing interrupt processing by the timer 19 in the image input device of this embodiment.

FIG. 8 is a block diagram showing a schematic configuration of an image input device according to a second embodiment.

[Explanation of symbols]

1 Encoder 2 LED array 3 Line image sensor 5 Shift register 13 Control circuit 16 Interrupt input port 17 Interrupt control circuit 18, 19 Timer 25 Image input shift register 29 Random access memory (RAM) 30 Read only memory (ROM) 31 Display control circuit 32 Display 33 Keyboard 34 Power supply circuit

Claims (1)

[Claims] Claim 1. An image input device that photoelectrically reads and inputs two-dimensional image information, the device comprising: an irradiating means for irradiating light onto an image information surface; and an irradiating means for scanning the image information surface. a photoelectric conversion means for inputting and photoelectrically converting the reflected light of the light irradiated by the photoelectric conversion means; a storage means for accumulating output data from the photoelectric conversion means; a detection means for detecting the scanning amount of the photoelectric conversion means; After lighting the irradiation means in accordance with the scanning amount detected by the detection means, storing image data from the photoelectric conversion means in the storage means, and storing a predetermined amount of image data in the storage means, An image input device comprising: a control means for controlling the irradiation means to turn off the light.