JPH04345359A - Picture reader - Google Patents

Abstract

PURPOSE:To obtain a picture reader by which the damage on constituting parts, or the deterioration of an original can be avoided, and a power consumption can be saved. CONSTITUTION:A picture reader 1 is equipped with a scanning means which reads picture information on the original by irradiating the original with a light, moving means which moves this scanning means to the prescribed direction of the original, first means which detects the operating state of the scanning means, second detecting means which detects the operating state of the moving means, and control means 20 which stops the irradiation with the light by the scanning means at the time of detecting the stoppage of the moving means by the second detecting means, when the first detecting means detects that the original is irradiated with the light by the scanning means. Thus, the damage on the constituting parts, or the deterioration of the original can be avoided, and the power consumption can be saved.

Description

[Detailed description of the invention]

[Purpose of the invention]

0001

[Industrial Field of Application] The present invention relates to an image reading device.
More specifically, the present invention relates to an image reading device that reads image information on a document and performs image information processing based on the image information.

0002

[Prior Art] Generally, facsimiles, scanners,
In an image reading device such as a CR, a contact type image sensor having the same width as the document width or a reduction type image sensor having a width smaller than the document width is used as an image reading means.

In the optical system of the contact type image sensor, the light source, the imaging lens, and the photoelectric conversion element all have the same width as the original, so the optical path length is short and it is easy to miniaturize and unitize.

[0004] Further, the optical system using the reduction type sensor uses a light source with the same width as the original, but since the photoelectric conversion element is smaller than the width of the original, an image is formed on the surface of the photoelectric conversion element using a lens. The optical path length is long, which makes it difficult to unitize and tends to increase the size.

By the way, no matter which of the above-mentioned optical systems is used, when reading the image information of a document with an image reading means, the document is irradiated with a light source and the reflected light is directed onto the photoelectric conversion element surface with a lens. It is forming an image. For this reason, the original and the light source are usually placed at a close distance of several millimeters or centimeters, although they are separated by a glass plate called an original table. On the other hand, in recent years, there has been a trend to further increase the amount of light from the light source due to demands for speeding up image reading speed or reading color originals.

Furthermore, as systems such as workstations have been upgraded, the use of image reading devices as standalone devices has decreased, but their use as one device in a system has increased. For this reason, if the system malfunctions due to some reason and communication becomes impossible, it is necessary to appropriately control the light source within the image reading device.

[0007]

[Problems to be Solved by the Invention] In other words, if the host computer malfunctions or communication becomes impossible due to the influence of external factors other than this device (static noise, radio noise, software reception errors, etc.), Abnormalities may occur in the carriage drive motor, motor driver, and drive transmission system in the image reading device that scans the image. In such cases, when the image reading device is reading a document or reading white shading data, the light source The normal sequence of driving the carriage with the light on is interrupted midway. As a result, the carriage remains stationary for a long time with the light source on, and the heat generated by the light source can cause damage to the platen glass, and the control circuit system can be damaged due to temperature rise inside the device. There were problems with functionality down, discoloration, and deformation of the original. Further, there is also the problem that power is wasted due to unnecessary lighting of the light source for a long time.

[0008] Therefore, the present invention improves the configuration of the device and
It is an object of the present invention to provide an image reading device that can avoid breakage and damage to component parts and deterioration of documents, and that does not waste power.

[Configuration of the invention]

0010

[Means for Solving the Problems] The present invention provides a scanning means for reading image information on a document by irradiating it with light, a moving means for moving the scanning means in a predetermined direction of the document, and an operation of the scanning means. a first detection means for detecting a state; a second detection means for detecting an operating state of the moving means; the first detection means detecting that light is irradiated by the scanning means; and control means for controlling light irradiation by the scanning means to stop when the second detection means detects that the moving means is stopped.

[0011]

[Operation] The operation of the image reading device will be explained below.

The scanning means of this apparatus is driven by a moving means, and reads the image information of the original by irradiating it with light while moving the original in a predetermined direction.

The operating state of the scanning means is detected by a first detecting means, and the operating state of the moving means is detected by a second detecting means.

[0014] The control means is configured such that when the first detection means detects that the light is irradiated by the scanning means, the second detection means stops the moving means. When this is detected, the light irradiation by the scanning means is stopped. This avoids breakage and damage to components and deterioration of documents due to unnecessary heating, and also eliminates power wastage.

[0015]

EXAMPLES Examples of the present invention will be described in detail below.

The image reading device 1 shown in FIG. 1 includes a box-shaped device body 1A, a document table glass 3 placed on the top surface of the device body 1A on which a document 2 is placed, and a document table glass 3 placed next to the document table glass 3. It consists of a white reference correction plate 5 to which white level correction data is attached for correcting an image signal containing shading distortion, and a first carriage 11 and a second carriage 12 arranged below the document table glass 3. A scanning means 13, a lens 9 disposed on the side of the second carriage 12, a CCD sensor 10 functioning as a second detection means as a photoelectric conversion element that converts an optical signal into an electric signal, and a control means 20 to be described later. It has a built-in control box 4.

The first carriage 11 includes a light source 6 that irradiates light onto the original 2, and a first mirror 7 that further reflects light reflected from the original 2 to the second carriage 12.

The second carriage 12 includes a pair of mirrors 8a and 8b that respectively reflect the light from the first mirror 7 and send it to the lens 9.

Next, the control system of the image reading device 1 will be explained with reference to FIG.

The image reading apparatus 1 is equipped with a control means 20 for controlling the entire apparatus. This control means 20 is
A PU 21, a program memory 22 that stores operation programs for the image reading device 1, a storage section 23 that stores various information and data, and a time management section 24 that manages the operation time of the image reading device 1. It is equipped with an interface 25 that sends and receives various commands and data to and from an external host computer 40.

The CPU 21 includes a light source driving section 31 that turns on and off the light source 6, and a light source driving section 31 that turns on and off the light source 6;
1, and a first stepping motor 32 serving as a moving means for driving the first carriage 11; an encoder 33, a second stepping motor 34 as a moving means for driving the second carriage 12, and a second stepping motor 34 for transmitting a drive pulse signal in the second stepping motor 34 as position detection information for the second carriage 12. a second encoder 3 functioning as a detection means for the first encoder;
5 and the CCD sensor 10 as second detection means are connected.

Next, the operation of the image reading device 1 will be explained.

When the CPU 21 receives a document start command from the host computer 40 with the document 2 placed on the document platen glass 3, the CPU 21 first gives a command to the first stepping motor 32 to start the home page. The first carriage 11 in the position is operated to stop the first mirror 7 in the first carriage 11 under the white reference correction plate 5. At this time, the light source 6 remains off, and black shading data is read from the CCD sensor 10 and stored in the black shading memory in the storage section 23 in the control means 20.

This black shading data is correction data used to remove dark level noise inherent in the CCD sensor 10. Next, the CPU 21 turns on the light source 6 via the light source drive section 31 and gives a command to the first stepping motor 32. As a result, the first carriage 11 scans the lower surface of the white reference correction plate 5, reads the white shading data, and transmits the read white shading data to the CCD sensor 10 through the optical system described above.
send to The CCD sensor 10 converts the white shading data into an electrical signal and sends it to the CPU 21.

The CPU 21 stores the white shading data from the CCD sensor 10 in the white shading memory in the storage section 23.

This white shading data is correction data used to remove bright level noise (high frequency distortion) specific to the CCD sensor 10 and low frequency distortion caused by optical systems such as light sources and lenses.

The first carriage 11 operates at twice the speed of the second carriage 12 under the control of the CPU 21.

Thereafter, the first carriage 11 moves in the installation direction of the document table glass 3 with the light source 6 inside the first carriage 11 turned on, and starts scanning the document 2 (in the sub-scanning direction). motion). The first carriage 11 performs a stable operation at a constant speed V when reading the original 2, and at this time the CCD sensor 10 is controlled by a synchronization signal of a constant period from the CPU 21.
The CPU 2 converts the optical signal imaged on the image into an electrical signal.
1 (operation in the main scanning direction).

After the image information is corrected with the black shading data and white shading data stored in each of the memories in the control means 20, it is transmitted to the host computer 40 via the interface 25.

Image information on the original 2 can be read by simultaneously performing the above-described operation in the sub-scanning direction and the operation in the main scanning direction on the original 2. When the scanning of the original 2 is completed, the light source 6 in the first carriage 11 is turned off, and the first carriage 11 returns to the home position and enters a standby state.

Next, the operation of the image reading device 1 will be described in further detail with reference to FIG.

In FIG. 3, power-on (ST1) indicates a state in which the power of the main body 1A of the apparatus is turned on, and then initial processing and standby processing (ST2, 3) are performed.
It enters a standby state waiting for a command from the host computer 40. In the initial processing, the control means 20 is initialized.

Further, in the standby processing, the home position of the first carriage 11 is detected, the lighting of the light source 6 is checked, and the host computer 40 and the interface 25 are connected to each other.
We are conducting operational checks, etc.

[0034] The CPU 21 is connected to the host computer 4
When a command is received from the host computer 40 (ST4), a parity check is performed on the command data (ST5), and if a parity error occurs, the process moves to a command error processing routine (ST8) and the host computer 40
Send command error to.

In the next parameter check (ST7), the command data received from the host computer 40 is compared with the commands prepared in advance in the program memory 22, and if the corresponding command does not exist, the process goes to the command error processing routine (ST8). and sends an illegal command error to the host computer 40.

When the CPU 21 receives a proper command, it performs a detection operation (ST9) to confirm that the light source 6 is turned on. Here, if some kind of abnormality occurs in the software and hardware due to the influence of some external cause or a malfunction within the main body 1A of the apparatus, and the first carriage 11 comes to a stopped state while the light source 6 remains lit, in this case, the above-mentioned The position detection information from the first encoder 33 is interrupted, and the CC
Since the detection level of the D sensor 10 continues to be high,
Based on the time management information of the time management unit 24, the CPU 21 determines that the first carriage 11 will not operate when the above-mentioned state has passed for t minutes (for example, 2 or 3 minutes) (ST10), and starts driving the light source. The light source 6 is forcibly turned off via the section 31 (ST11), and the host computer 40 enters a state in which it can receive a new command (ST4) and enters a standby state.

This is because if the light source 6 is turned on and the first carriage 11 remains stopped for a long time, the heat generated from the light source 6 may cause damage to the document table glass 3, discoloration or deformation of the document 2, and damage to the device. This is to prevent or predict a rise in temperature within the main body 1A and wasteful power consumption, and to dramatically improve safety and economic efficiency. Particularly, the effectiveness of the above-mentioned operation is extremely high as safety of man-machines has recently become more important.

Next, if there is no abnormality in the operation as described above, it is confirmed that the light source 6 is turned off, and the CPU
21 performs command analysis of command data received from the host computer 40 (ST12). At this time, the command is a test command (ST13),
Read start command (ST14), execution command (ST
15), status request command (ST16), and the process proceeds to each processing routine.

The test command processing routine is a test mode process (S
T17), and is used for various debugging and evaluation of the device main body 1A.

The reading start command processing routine is a command system mainly for performing sequence operations for scanning the original 2 on the original table glass 3 and reading its image information.

[0041] The CPU 21 issues a reading start command (ST1
4), the light source 6 is turned on, and the optical signal focused on the CCD sensor 10 is converted into an electrical signal and sent to the CPU.
21, where the CPU 21 detects the transfer efficiency of the CCD sensor 10 (ST18). Then, optimum control conditions for the CCD sensor 10 are found from this transfer efficiency data (ST19), and a command is given to a control circuit for the CCD sensor 10 (not shown) in the control means 20. Thereafter, the carriage 11 is scanned under the original to read the image information of the original (ST20), and the image information is transferred to the host computer 40.

The execution command processing routine is a command system (ST21) for changing the condition setting values of the apparatus main body 1A, ie, the document size, magnification, reading circuit, etc.

The status request command processing routine transmits the current state of the device body 1A to a host (not shown).
This is an instruction system for ST22).

The present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the invention.

[0045]

According to the present invention described above, with the above-described configuration, it is possible to properly manage the turning off of the light source in the event of an abnormality, and prevent damage or damage to each component or the component parts of the document or deterioration of the document. Therefore, it is possible to provide an economically superior image reading device that does not cause power wastage.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an image reading device that is an embodiment of the present invention.

[
FIG. 2 is a block diagram showing a control system of an image reading device that is an embodiment of the present invention

FIG. 3 is a flowchart showing the operation of an image reading device that is an embodiment of the present invention.

[Explanation of symbols]

1 Image reading device 2 Manuscript 3　Original table glass 6. Light source 10 CCD sensor 11 First carriage 12 Second carriage 20 Control means 33 First encoder 35 Second encoder

Claims (1)

[Claims] 1. A scanning device that reads image information on a document by irradiating it with light, a moving device that moves the scanning device in a predetermined direction of the document, and a first detection device that detects the operating state of the scanning device. means, a second detection means for detecting the operating state of the moving means, and when the first detection means detects that light is irradiated by the scanning means; An image reading apparatus comprising: a control means for controlling light irradiation by the scanning means to stop when the detection means detects that the moving means is stopped.