JP2005151269A

JP2005151269A - Image scanner

Info

Publication number: JP2005151269A
Application number: JP2003387410A
Authority: JP
Inventors: Toshiaki Kamishiro; 敏昭神代
Original assignee: Ricoh Co Ltd
Current assignee: Ricoh Co Ltd
Priority date: 2003-11-18
Filing date: 2003-11-18
Publication date: 2005-06-09

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image scanner for appropriately adjusting quantity of light of a two-light light source and appropriately setting the output level of a photoelectric conversion element to acquire a read image of good image quality. <P>SOLUTION: In a scanner 1, a reading part control circuit 21 successively lights up two LEDs 5a and 5b with predetermined quantity of light independently of LED driving drivers 22 and 23 before reading a document, and sets specified quantity of light when the two LEDs 5a and 5b are simultaneously lit up in reading the document for each of LCDs 5a and 5b based on a photoelectric conversion quantity of a CCD 10 of reflected light from a white reference plate, when respective LCDs 5a and 5b are independently and successively lit up in the LED driving drivers 22 and 23. When the document is read, the drivers 22 and 23 drive to light up the two LEDs 5a and 5b with the specified quantity of light, respectively. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

本発明は、画像読取装置に関し、詳細には、２灯の光源の光量を適切に調整して光電変換手段の出力レベルを適切に設定し、良好な画像品質の読取画像を得る画像読取装置に関する。 The present invention relates to an image reading apparatus, and more particularly to an image reading apparatus that appropriately adjusts the light amounts of two light sources to appropriately set the output level of a photoelectric conversion unit and obtain a read image with good image quality. .

スキャナ、複写装置、ファクシミリ装置等の画像読取装置は、光源として、蛍光灯、Ｘｅ（キセノン）管あるいはＬＥＤ（Light Emitting Diode）等が用いられている。画像読取装置は、この光源から原稿に光を照射して、原稿からの反射光をＣＣＤ（Charge Coupled Device ）等の光電変換素子に入射し、光電変換素子で電気信号に変換して原稿の画像を読み取っている。 Image reading apparatuses such as scanners, copying machines, and facsimile machines use fluorescent lamps, Xe (xenon) tubes, LEDs (Light Emitting Diodes), or the like as light sources. The image reading device irradiates the original with light from the light source, enters the reflected light from the original into a photoelectric conversion element such as a CCD (Charge Coupled Device), and converts the light into an electrical signal by the photoelectric conversion element. Reading.

したがって、画像読取装置においては、光源の光量が適切であることが原稿の画像を良好な状態で読み取る上で重要である。 Therefore, in the image reading apparatus, it is important for the image of the document to be read in a good state that the light amount of the light source is appropriate.

そこで、従来から光源の光量調整を行う画像読取装置が種々提案されており、例えば、特許文献１では、光源の点灯から所定時間後にイメージセンサに結像する光の波長分布を検出して、この検出結果の波長分布に基づいて光源あるいはこの光源周辺の温度を推定し、この温度に基づいて光源への供給電力量を制御する技術が開示されている。 Therefore, various image reading apparatuses for adjusting the light amount of the light source have been proposed in the past. For example, Patent Document 1 detects the wavelength distribution of light that forms an image on the image sensor after a predetermined time has elapsed since the light source is turned on. A technique for estimating a light source or a temperature around the light source based on a wavelength distribution of a detection result and controlling an amount of power supplied to the light source based on the temperature is disclosed.

また、従来、本出願人は、先に、シェーディング補正用の基準白板の読み取り時の照射光量が原稿読み取り時の照射光量と異なるように調光する技術を開示している（特許文献２参照）。 Conventionally, the present applicant has previously disclosed a technique for dimming light so that the amount of irradiation light at the time of reading a reference white plate for shading correction is different from the amount of light irradiation at the time of document reading (see Patent Document 2). .

特開２００２−２０９０５８号公報JP 2002-209058 A 特開平１１−１８７２６２号公報JP 11-187262 A

しかしながら、上記従来技術にあっては、複数の光源を使用した画像読取装置については考慮されておらず、改良の必要があった。 However, in the above-described prior art, an image reading apparatus using a plurality of light sources is not taken into consideration and needs to be improved.

すなわち、従来、光量不足になると、適切に原稿の画像を読み取ることができないため、従来から光源を２灯使用した構成として原稿を読み取っている画像読取装置がある。このような複数、例えば、２灯の光源を用いた場合、複数の光源がバランスよく原稿面を照射する必要がある。 That is, conventionally, when the amount of light is insufficient, an image of a document cannot be appropriately read. Therefore, there is an image reading apparatus that conventionally reads a document as a configuration using two light sources. When such a plurality of light sources, for example, two light sources are used, the plurality of light sources need to irradiate the document surface in a balanced manner.

ところが、各々の光源の光量はばらつきがあり、２灯構成にすると、光源全体としてのばらつきが２倍となり、ＣＣＤ等の受光素子への最適な出力レベルを得るには、設計上非常に難しい構成となっている。 However, the amount of light from each light source varies, and if a two-lamp configuration is used, the variation of the entire light source is doubled, and it is extremely difficult to design in order to obtain an optimum output level to a light receiving element such as a CCD. It has become.

特に、２灯構成の光源で、２倍のばらつきを考慮すると、ＣＣＤの飽和電圧以下に光源の出力レベルの上限を抑える必要があるため、目標値となるＣＣＤ出力レベルを低くする必要があり、Ｓ／Ｎが低下して、画質劣化の一因となる。 In particular, in the case of a light source having a two-lamp configuration, in consideration of twice the variation, it is necessary to suppress the upper limit of the output level of the light source below the saturation voltage of the CCD. The S / N is reduced, which contributes to image quality degradation.

そこで、請求項１記載の発明は、相対向して配置された２灯の光源から原稿に光を照射して当該原稿からの反射光を光電変換手段に導入して当該光電変換手段が入射光を光電変換することで当該原稿を読み取るに際して、制御手段が、当該原稿の読取前に、２灯のそれぞれの光源を光量調整手段に独立して所定光量で順次点灯させて、当該各光源を独立して順次点灯させたときの所定の基準部材からの反射光の光電変換手段の光電変換量に基づいて、原稿読取時の当該２灯の光源を同時に点灯させたときの設定光量を各光源毎に、２灯の光源をそれぞれ独立して光量調整する光量調整手段に設定し、当該原稿の読取時に、光量調整手段が、当該設定光量で２灯の光源をそれぞれ点灯駆動させることにより、適正な光量を各光源に対して設定して点灯して、２灯同時点灯時においても、十分な光電変換手段の出力レベルを得ることができるようにするとともに、Ｓ／Ｎをも向上させ、読取画像の画像品質を向上させる画像読取装置を提供するを目的としている。 In view of this, the invention according to claim 1 irradiates the original with light from two light sources arranged opposite to each other, introduces reflected light from the original into the photoelectric conversion means, and the photoelectric conversion means is incident light. When reading the original by photoelectric conversion, the control means turns on each of the two light sources sequentially with a predetermined light quantity independently of the light quantity adjusting means before reading the original, so that each of the light sources becomes independent. Then, based on the photoelectric conversion amount of the photoelectric conversion means of the reflected light from the predetermined reference member when sequentially turned on, the set light amount when the two light sources at the time of document reading are simultaneously turned on is set for each light source. In addition, the two light sources are set as the light amount adjusting means for adjusting the light amount independently, and the light amount adjusting means drives the two light sources to light up with the set light amount when reading the document. Set the amount of light for each light source. An image reading apparatus that is lit and that can obtain a sufficient output level of the photoelectric conversion means even when two lights are lit simultaneously, improves S / N, and improves the image quality of a read image. It is intended to provide.

請求項２記載の発明は、制御手段が、２灯の光源をそれぞれ独立して点灯させて光量調整手段に設定光量を設定した後、光量調整手段に２灯の光源を当該設定光量で同時に点灯させ、当該２灯の光源を同時に点灯させたときの光電変換手段の光電変換量に基づいて、光量調整手段の各光源の設定光量を補正し、原稿の読取時に、光量調整手段が、補正後の設定光量で２灯の光源をそれぞれ点灯駆動させることにより、より一層適正な光量を各光源に対して設定して点灯して、２灯同時点灯時においても、より一層適切な光電変換手段の出力レベルを得ることができるようにするとともに、Ｓ／Ｎをもより一層向上させ、読取画像の画像品質をより一層向上させる画像読取装置を提供するを目的としている。 According to the second aspect of the present invention, after the control unit turns on the two light sources independently and sets the set light amount in the light amount adjusting unit, the two light sources are simultaneously turned on in the light amount adjusting unit with the set light amount. Then, based on the photoelectric conversion amount of the photoelectric conversion means when the two light sources are turned on at the same time, the set light quantity of each light source of the light quantity adjustment means is corrected. By turning on the two light sources with the set light amount, a more appropriate light amount is set for each light source and the light source is turned on. An object of the present invention is to provide an image reading apparatus capable of obtaining an output level, further improving S / N, and further improving image quality of a read image.

請求項３記載の発明は、相対向して配置された２灯の光源から原稿に光を照射して当該原稿からの反射光を光電変換手段に導入して当該光電変換手段が入射光を光電変換することで当該原稿を読み取るに際して、制御手段が、原稿の読取前に、２灯の光源のうちのいずれか１灯の光源を光量調整手段に所定光量で点灯させて、当該１灯の光源を点灯させたときの所定の基準部材からの反射光の光電変換手段の光電変換量に基づいて、原稿読取時の当該２灯の光源を同時に点灯させたときの設定光量を各光源毎に、２灯の光源をそれぞれ独立して光量調整する光量調整手段に設定し、原稿の読取時に、光量調整手段が、設定光量で２灯の光源をそれぞれ点灯駆動させることにより、少ない光源の点灯回数で、適正な光量を各光源に対して設定して点灯して、２灯同時点灯時においても、十分な光電変換手段の出力レベルを得ることができるようにするとともに、簡単にＳ／Ｎをも向上させ、読取画像の画像品質を向上させる画像読取装置を提供するを目的としている。 The invention according to claim 3 irradiates the original with light from two light sources arranged opposite to each other, introduces reflected light from the original into the photoelectric conversion means, and the photoelectric conversion means converts the incident light into photoelectric light. When the original is read by conversion, the control means turns on one of the two light sources with a predetermined light amount to the light quantity adjusting means before reading the original, and the one light source On the basis of the photoelectric conversion amount of the photoelectric conversion means of the reflected light from the predetermined reference member when the light is turned on, the set light amount when the two light sources at the time of reading the document are turned on simultaneously for each light source, Two light sources are set as light intensity adjusting means for adjusting the light intensity independently, and when reading a document, the light intensity adjusting means drives and turns on the two light sources with the set light quantity, thereby reducing the number of times the light source is turned on. Set the appropriate amount of light for each light source. Lights up so that a sufficient output level of the photoelectric conversion means can be obtained even when two lamps are lit simultaneously, and the S / N can be easily improved to improve the image quality of the read image. The purpose is to provide a device.

請求項４記載の発明は、制御手段が、２灯の光源をそれぞれ光量調整手段に独立して所定光量で順次点灯させたときの光電変換手段の出力光量に基づいて、当該光源の不点灯、当該光源の主走査方向の一部分の光量不足等の光源異常現象の有無を検出して、当該光源異常現象から読取画像に異常画像が発生するか否かを判断し、当該異常画像が発生すると判断すると、当該異常現象のある光源の点灯を消灯させるものとして、光量調整手段に設定するとともに、原稿読取時の他の光源の設定光量を光量調整手段に設定し、光量調整手段が、原稿読取時に、消灯の指示された光源の点灯を消灯させるとともに、他の光源を設定光量で点灯駆動させることにより、光源に異常がある場合にも、適正な光量を光源に対して設定して点灯して、十分な光電変換手段の出力レベルを得ることができるようにするとともに、簡単にＳ／Ｎをも向上させ、読取画像の画像品質を向上させる画像読取装置を提供するを目的としている。 According to a fourth aspect of the present invention, the control means does not turn on the light source based on the output light amount of the photoelectric conversion means when the two light sources are sequentially turned on with a predetermined light amount independently of the light amount adjusting means. By detecting the presence or absence of a light source abnormality phenomenon such as insufficient light quantity in a part of the light source in the main scanning direction, it is determined whether or not an abnormal image is generated in the read image from the light source abnormality phenomenon, and it is determined that the abnormal image is generated. Then, the light source having the abnormal phenomenon is turned off and set in the light amount adjusting unit, and the set light amount of the other light source at the time of document reading is set in the light amount adjusting unit. By turning off the light source that is instructed to turn off and driving other light sources with the set light amount, even if there is an abnormality in the light source, the proper light amount is set for the light source and turned on. ,enough Together to be able to obtain the output level of the photoelectric conversion means, briefly also to improve the S / N, it is an object to provide an image reading apparatus to improve image quality of the read image.

請求項５記載の発明は、制御手段が、点灯させる側の光源の設定光量を、本来の１灯分の目標光量よりも高めの光量に光量調整手段に設定することにより、Ｓ／Ｎをより一層向上させ、読取画像の画像品質を向上させる画像読取装置を提供するを目的としている。 According to the fifth aspect of the present invention, the control means sets the light quantity setting means of the light source on the lighting side to the light quantity adjustment means to a light quantity higher than the original target light quantity for one lamp, so that the S / N is further increased. An object of the present invention is to provide an image reading apparatus that can be further improved to improve the image quality of a read image.

請求項１記載の発明の画像読取装置は、相対向して配置された２灯の光源から原稿に光を照射して当該原稿からの反射光を光電変換手段に導入して当該光電変換手段が入射光を光電変換することで当該原稿を読み取る画像読取装置において、前記２灯の光源をそれぞれ独立して光量調整する光量調整手段と、前記原稿の読取前に、前記２灯のそれぞれの光源を前記光量調整手段に独立して所定光量で順次点灯させて、当該各光源を独立して順次点灯させたときの所定の基準部材からの反射光の前記光電変換手段の光電変換量に基づいて、前記原稿読取時の当該２灯の光源を同時に点灯させたときの設定光量を前記各光源毎に前記光量調整手段に設定する制御手段と、を備え、前記原稿の読取時に、前記光量調整手段が前記設定光量で前記２灯の光源をそれぞれ点灯駆動させることにより、上記目的を達成している。 In the image reading apparatus according to the first aspect of the present invention, the original is irradiated with light from two light sources arranged opposite to each other, and the reflected light from the original is introduced into the photoelectric conversion means. In an image reading apparatus that reads the document by photoelectrically converting incident light, a light amount adjusting unit that independently adjusts the light amount of each of the two light sources, and each of the two light sources before reading the document. Based on the photoelectric conversion amount of the photoelectric conversion means of the reflected light from a predetermined reference member when the light quantity adjusting means is turned on sequentially with a predetermined light quantity and each light source is turned on sequentially. Control means for setting, in the light quantity adjusting means, a set light quantity when the two light sources at the time of reading the original are simultaneously turned on, and when the original is read, the light quantity adjusting means comprises: The two lights with the set light quantity By each lighting drive of the light source, it has achieved the above objects.

この場合、例えば、請求項２に記載するように、前記制御手段は、前記２灯の光源をそれぞれ独立して点灯させて前記光量調整手段に設定光量を設定した後、前記光量調整手段に前記２灯の光源を当該設定光量で同時に点灯させ、当該２灯の光源を同時に点灯させたときの前記光電変換手段の光電変換量に基づいて、前記光量調整手段の各光源の前記設定光量を補正し、前記原稿の読取時に、前記光量調整手段が前記補正後の設定光量で前記２灯の光源をそれぞれ点灯駆動させるものであってもよい。 In this case, for example, as described in claim 2, the control unit turns on the two light sources independently and sets a set light amount in the light amount adjusting unit, and then sets the set light amount in the light amount adjusting unit. The two light sources are turned on simultaneously with the set light quantity, and the set light quantity of each light source of the light quantity adjusting means is corrected based on the photoelectric conversion amount of the photoelectric conversion means when the two light sources are turned on simultaneously. In addition, when the original is read, the light amount adjusting unit may drive the two light sources to light with the set light amount after the correction.

請求項３記載の発明の画像読取装置は、相対向して配置された２灯の光源から原稿に光を照射して当該原稿からの反射光を光電変換手段に導入して当該光電変換手段が入射光を光電変換することで当該原稿を読み取る画像読取装置において、前記２灯の光源をそれぞれ独立して光量調整する光量調整手段と、前記原稿の読取前に、前記２灯の光源のうちのいずれか１灯の光源を前記光量調整手段に所定光量で点灯させて、当該１灯の光源を点灯させたときの所定の基準部材からの反射光の前記光電変換手段の光電変換量に基づいて、前記原稿読取時の当該２灯の光源を同時に点灯させたときの設定光量を前記各光源毎に前記光量調整手段に設定する制御手段と、を備え、前記原稿の読取時に、前記光量調整手段が前記設定光量で前記２灯の光源をそれぞれ点灯駆動させることにより、上記目的を達成している。 According to a third aspect of the present invention, there is provided an image reading apparatus in which light is applied to a document from two light sources arranged opposite to each other, and reflected light from the document is introduced into a photoelectric conversion unit. In an image reading apparatus that reads the document by photoelectrically converting incident light, a light amount adjusting unit that independently adjusts the light amounts of the two light sources, and before reading the document, Based on the photoelectric conversion amount of the photoelectric conversion means of the reflected light from a predetermined reference member when any one light source is turned on with a predetermined light amount on the light amount adjusting means and the one light source is turned on. Control means for setting the light amount adjusting means for each light source when the two light sources are simultaneously turned on at the time of reading the document, and the light amount adjusting means at the time of reading the document. Is the set light quantity and the two lights The by lighting drive respectively, it has achieved the above objects.

上記請求項１または請求項２の場合、例えば、請求項４に記載するように、前記制御手段は、前記２灯の光源をそれぞれ前記光量調整手段に独立して所定光量で順次点灯させたときの前記光電変換手段の出力光量に基づいて、当該光源の不点灯、当該光源の主走査方向の一部分の光量不足等の光源異常現象の有無を検出して、当該光源異常現象から読取画像に異常画像が発生するか否かを判断し、当該異常画像が発生すると判断すると、当該異常現象のある光源の点灯を消灯させるものとして、前記光量調整手段に設定するとともに、前記原稿読取時の他の光源の設定光量を前記光量調整手段に設定し、前記光量調整手段が、原稿読取時に、前記消灯の指示された光源の点灯を消灯させるとともに、他の光源を前記設定光量で点灯駆動させるものであってもよい。 In the case of the first or second aspect, for example, as described in the fourth aspect, the control unit sequentially turns on the two light sources sequentially with a predetermined light amount independently of the light amount adjusting unit. Based on the output light quantity of the photoelectric conversion means, the presence or absence of a light source abnormality phenomenon such as non-lighting of the light source or insufficient light quantity in a part of the light source in the main scanning direction is detected, and the read image is abnormal from the light source abnormality phenomenon It is determined whether or not an image is generated, and if it is determined that the abnormal image is generated, the light source having the abnormal phenomenon is turned off and set in the light amount adjusting unit, The set light amount of the light source is set in the light amount adjusting unit, and the light amount adjusting unit turns off the light source instructed to be turned off when reading a document and drives other light sources to turn on with the set light amount. It may be of.

また、例えば、請求項５に記載するように、前記制御手段は、前記点灯させる側の光源の前記設定光量を、本来の１灯分の目標光量よりも高めの光量に前記光量調整手段に設定するものであってもよい。 For example, as described in claim 5, the control unit sets the set light amount of the light source on the lighting side to the light amount adjusting unit to a light amount higher than the original target light amount for one lamp. You may do.

請求項１記載の発明の画像読取装置によれば、相対向して配置された２灯の光源から原稿に光を照射して当該原稿からの反射光を光電変換手段に導入して当該光電変換手段が入射光を光電変換することで当該原稿を読み取るに際して、制御手段が、当該原稿の読取前に、２灯のそれぞれの光源を光量調整手段に独立して所定光量で順次点灯させて、当該各光源を独立して順次点灯させたときの所定の基準部材からの反射光の光電変換手段の光電変換量に基づいて、原稿読取時の当該２灯の光源を同時に点灯させたときの設定光量を各光源毎に、２灯の光源をそれぞれ独立して光量調整する光量調整手段に設定し、当該原稿の読取時に、光量調整手段が、当該設定光量で２灯の光源をそれぞれ点灯駆動させるので、適正な光量を各光源に対して設定して点灯して、２灯同時点灯時においても、十分な光電変換手段の出力レベルを得ることができるとともに、Ｓ／Ｎをも向上させることができ、読取画像の画像品質を向上させることができる。 According to the image reading apparatus of the first aspect of the present invention, the original is irradiated with light from the two light sources arranged opposite to each other, and the reflected light from the original is introduced into the photoelectric conversion means to perform the photoelectric conversion. When the means reads the original by photoelectrically converting the incident light, the control means turns on each of the two light sources sequentially with a predetermined light amount independently of the light amount adjusting means before reading the original, Based on the photoelectric conversion amount of the photoelectric conversion means of the reflected light from the predetermined reference member when each light source is sequentially turned on independently, the set light amount when the two light sources are simultaneously turned on at the time of document reading For each light source, the two light sources are set as light amount adjusting means for independently adjusting the light amount, and the light amount adjusting means drives and turns on the two light sources with the set light amount when reading the document. , Appropriate light intensity for each light source Even when two lights are turned on at the same time, a sufficient output level of the photoelectric conversion means can be obtained, S / N can be improved, and the image quality of the read image is improved. Can do.

請求項２記載の発明の画像読取装置によれば、制御手段が、２灯の光源をそれぞれ独立して点灯させて光量調整手段に設定光量を設定した後、光量調整手段に２灯の光源を当該設定光量で同時に点灯させ、当該２灯の光源を同時に点灯させたときの光電変換手段の光電変換量に基づいて、光量調整手段の各光源の設定光量を補正し、原稿の読取時に、光量調整手段が、補正後の設定光量で２灯の光源をそれぞれ点灯駆動させるので、より一層適正な光量を各光源に対して設定して点灯して、２灯同時点灯時においても、より一層適切な光電変換手段の出力レベルを得ることができるとともに、Ｓ／Ｎをもより一層向上させることができ、読取画像の画像品質をより一層向上させることができる。 According to the image reading apparatus of the second aspect of the present invention, after the control unit turns on the two light sources independently and sets the set light amount in the light amount adjusting unit, the control unit supplies the two light sources to the light amount adjusting unit. Based on the photoelectric conversion amount of the photoelectric conversion means when the two light sources are turned on simultaneously with the set light quantity, the set light quantity of each light source of the light quantity adjusting means is corrected, and the light quantity is The adjusting means drives the two light sources to light up with the corrected set light amount, so that a more appropriate light amount is set for each light source and lighted. The output level of the photoelectric conversion means can be obtained, the S / N can be further improved, and the image quality of the read image can be further improved.

請求項３記載の発明の画像読取装置によれば、相対向して配置された２灯の光源から原稿に光を照射して当該原稿からの反射光を光電変換手段に導入して当該光電変換手段が入射光を光電変換することで当該原稿を読み取るに際して、制御手段が、原稿の読取前に、２灯の光源のうちのいずれか１灯の光源を光量調整手段に所定光量で点灯させて、当該１灯の光源を点灯させたときの所定の基準部材からの反射光の光電変換手段の光電変換量に基づいて、原稿読取時の当該２灯の光源を同時に点灯させたときの設定光量を各光源毎に、２灯の光源をそれぞれ独立して光量調整する光量調整手段に設定し、原稿の読取時に、光量調整手段が、設定光量で２灯の光源をそれぞれ点灯駆動させるので、少ない光源の点灯回数で、適正な光量を各光源に対して設定して点灯して、２灯同時点灯時においても、十分な光電変換手段の出力レベルを得ることができるとともに、簡単にＳ／Ｎをも向上させることができ、読取画像の画像品質を向上させることができる。 According to the image reading apparatus of the third aspect of the present invention, the original is irradiated with light from two light sources arranged opposite to each other, and the reflected light from the original is introduced into the photoelectric conversion means, and the photoelectric conversion is performed. When the means reads the document by photoelectrically converting the incident light, the control means turns on one of the two light sources to the light amount adjusting means with a predetermined light amount before reading the document. Based on the photoelectric conversion amount of the photoelectric conversion means of the reflected light from the predetermined reference member when the one light source is turned on, the set light amount when the two light sources are simultaneously turned on during document reading Is set for each light source as a light amount adjusting means for independently adjusting the light amount of the two light sources, and the light amount adjusting means drives and turns on the two light sources with the set light amount when reading a document. Appropriate amount of light for each light source In contrast, even when two lamps are lit at the same time, a sufficient output level of the photoelectric conversion means can be obtained and the S / N can be easily improved, and the image quality of the read image can be improved. Can be improved.

請求項４記載の発明の画像読取装置によれば、制御手段が、２灯の光源をそれぞれ光量調整手段に独立して所定光量で順次点灯させたときの光電変換手段の出力光量に基づいて、当該光源の不点灯、当該光源の主走査方向の一部分の光量不足等の光源異常現象の有無を検出して、当該光源異常現象から読取画像に異常画像が発生するか否かを判断し、当該異常画像が発生すると判断すると、当該異常現象のある光源の点灯を消灯させるものとして、光量調整手段に設定するとともに、原稿読取時の他の光源の設定光量を光量調整手段に設定し、光量調整手段が、原稿読取時に、消灯の指示された光源の点灯を消灯させるとともに、他の光源を設定光量で点灯駆動させるので、光源に異常がある場合にも、適正な光量を光源に対して設定して点灯して、十分な光電変換手段の出力レベルを得ることができるとともに、簡単にＳ／Ｎをも向上させることができ、読取画像の画像品質を向上させることができる。 According to the image reading apparatus of the invention described in claim 4, based on the output light quantity of the photoelectric conversion means when the control means turns on the two light sources sequentially with a predetermined light quantity independently of the light quantity adjustment means, Detecting the presence or absence of an abnormal light source phenomenon such as non-lighting of the light source, insufficient light quantity in a part of the light source in the main scanning direction, and determining whether or not an abnormal image occurs in the read image from the abnormal light source phenomenon; When it is determined that an abnormal image occurs, the light source having the abnormal phenomenon is turned off and set in the light amount adjusting unit, and the set light amount of the other light source at the time of document reading is set in the light amount adjusting unit to adjust the light amount. The unit turns off the light source that is instructed to turn off at the time of reading the document and drives other light sources to turn on with the set light amount. Point To, it is possible to obtain the output level of sufficient photoelectric conversion means, easily also can improve the S / N, it is possible to improve the image quality of the read image.

請求項５記載の発明の画像読取装置によれば、制御手段が、点灯させる側の光源の設定光量を、本来の１灯分の目標光量よりも高めの光量に光量調整手段に設定するので、Ｓ／Ｎをより一層向上させることができ、読取画像の画像品質を向上させることができる。 According to the image reading apparatus of the fifth aspect of the invention, the control unit sets the set light amount of the light source to be turned on to the light amount adjusting unit to a light amount higher than the original target light amount for one lamp. The S / N can be further improved, and the image quality of the read image can be improved.

以下、本発明の好適な実施例を添付図面に基づいて詳細に説明する。なお、以下に述べる実施例は、本発明の好適な実施例であるから、技術的に好ましい種々の限定が付されているが、本発明の範囲は、以下の説明において特に本発明を限定する旨の記載がない限り、これらの態様に限られるものではない。 Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, since the Example described below is a suitable Example of this invention, various technically preferable restrictions are attached | subjected, However, The scope of the present invention limits this invention especially in the following description. As long as there is no description of the effect, it is not restricted to these aspects.

図１〜図６は、本発明の画像読取装置の第１実施例を示す図であり、図１は、本発明の画像読取装置の第１実施例を適用したスキャナ１の正面概略構成図である。なお、本実施例は、請求項１に対応するものである。 1 to 6 are diagrams showing a first embodiment of the image reading apparatus of the present invention. FIG. 1 is a schematic front view of a scanner 1 to which the first embodiment of the image reading apparatus of the present invention is applied. is there. This embodiment corresponds to claim 1.

図１において、スキャナ１は、本体筐体２の上部にコンタクトガラス３が設けられており、コンタクトガラス３上に、白基準板（所定の基準部材）４が配置されているとともに、原稿Ｇがセットされる。 In FIG. 1, a scanner 1 is provided with a contact glass 3 on an upper portion of a main body housing 2, a white reference plate (predetermined reference member) 4 is disposed on the contact glass 3, and a document G is Set.

本体筐体２の内部には、図示しない第１走行体に搭載された光源５と第１ミラー６、図示しない第２走行体に搭載された第２ミラー７と第３ミラー８、レンズ９及びＣＣＤ（Charge Coupled Device ）１０等からなる露光走査光学系１１が配設されており、ＣＣＤ（撮像デバイス）１０は、ＣＣＤ基板１２に取り付けられている。 Inside the main body housing 2, a light source 5 and a first mirror 6 mounted on a first traveling body (not shown), a second mirror 7 and a third mirror 8 mounted on a second traveling body (not shown), a lens 9, and An exposure scanning optical system 11 composed of a CCD (Charge Coupled Device) 10 or the like is provided, and the CCD (imaging device) 10 is attached to a CCD substrate 12.

露光走査光学系１１は、第１走行体と第２走行体が図示しない走行体モータにより水平方向（副走査方向：図１の左右方向）に移動され、第１走行体上の光源５からコンタクトガラス３上に載置された原稿Ｇに光を照射して、当該原稿Ｇで反射された光の反射光を第１走行体上の第１ミラー６で第２走行体方向に反射し、第２走行体上の第２ミラー７及び第３ミラー８で第１走行体から入射される光を順次反射して、レンズ９方向に出射させる。レンズ９は、第２走行体から入射される光をＣＣＤ１０に集光して照射させる。ＣＣＤ（光電変換手段）１０は、１次元に複数の光電変換素子としてＣＣＤ素子が配列されており、レンズ９から入射される入射光を光電変換して、アナログの画像データ（画像信号）を出力する。 In the exposure scanning optical system 11, the first traveling body and the second traveling body are moved in the horizontal direction (sub-scanning direction: left and right direction in FIG. 1) by a traveling body motor (not shown) and contacted from the light source 5 on the first traveling body. The document G placed on the glass 3 is irradiated with light, the reflected light of the light reflected by the document G is reflected by the first mirror 6 on the first traveling body toward the second traveling body, The light incident from the first traveling body is sequentially reflected by the second mirror 7 and the third mirror 8 on the two traveling bodies and emitted in the direction of the lens 9. The lens 9 collects and irradiates the light incident from the second traveling body on the CCD 10. A CCD (photoelectric conversion means) 10 has a plurality of photoelectric conversion elements arranged in one dimension, and photoelectrically converts incident light incident from the lens 9 and outputs analog image data (image signal). To do.

そして、露光走査光学系１１は、原稿Ｇの読み取りに先立って、第１走行体と第２走行体を白基準板４を読み取る位置に移動させ、白基準板４を読み取って、シェーディング補正用の基準データを取得する。 Prior to reading the document G, the exposure scanning optical system 11 moves the first traveling body and the second traveling body to a position where the white reference plate 4 is read, reads the white reference plate 4, and performs shading correction. Get reference data.

上記光源５は、例えば、図２に示すように、ＬＥＤ５ａとＬＥＤ５ｂの２灯で構成されているが、２本のキセノン（Ｘｅ）管で構成されていてもよい。 For example, as shown in FIG. 2, the light source 5 is composed of two LEDs 5a and 5b, but may be composed of two xenon (Xe) tubes.

そして、スキャナ１は、その読取制御部２０とＣＣＤ基板１２が、図３に示すように、構成されており、ＣＣＤ基板１２には、上述のように、ＬＥＤ５ａとＬＥＤ５ｂが設けられている。 In the scanner 1, the reading control unit 20 and the CCD substrate 12 are configured as shown in FIG. 3, and the CCD substrate 12 is provided with the LEDs 5a and 5b as described above.

読取制御部２０には、読取制御回路２１、ＬＥＤ５ａ用のＬＥＤ駆動ドライバ２２とＬＥＤ５ｂ用のＬＥＤ駆動ドライバ２３及びＬＥＤ電源部２４等が設けられており、ＬＥＤ電源部２４からＣＣＤ基板１２の各ＬＥＤ５ａ、ＬＥＤ５ｂに駆動電源を供給する。 The reading control unit 20 is provided with a reading control circuit 21, an LED drive driver 22 for the LED 5a, an LED drive driver 23 for the LED 5b, an LED power supply unit 24, and the like. The drive power is supplied to the LED 5b.

ＬＥＤ駆動ドライバ（光量調整手段）２２とＬＥＤ駆動ドライバ（光量調整手段）２３は、ＬＥＤ５ａとＬＥＤ５ｂの点灯デューティ（ｄｕｔｙ）を調整して、ＬＥＤ５ａとＬＥＤ５ｂの出力調整を行う。 The LED drive driver (light quantity adjusting means) 22 and the LED drive driver (light quantity adjusting means) 23 adjust the output duty of the LEDs 5a and 5b by adjusting the lighting duty of the LEDs 5a and 5b.

読取部制御回路（制御手段）２１は、ＬＥＤ駆動ドライバ２２とＬＥＤ駆動ドライバ２３にＬＥＤ駆動制御信号を出力して、ＬＥＤ駆動ドライバ２２とＬＥＤ駆動ドライバ２３によるＬＥＤ５ａとＬＥＤ５ｂの点灯デューティ（設定光量）を制御する。 The reading unit control circuit (control unit) 21 outputs an LED drive control signal to the LED drive driver 22 and the LED drive driver 23, and the lighting duty (set light amount) of the LEDs 5a and 5b by the LED drive driver 22 and the LED drive driver 23. To control.

そして、読取制御回路２１は、原稿Ｇの読み取りに先立って、第１走行体と第２走行体を白基準板４を読み取る位置に移動させて、ＬＥＤ駆動ドライバ２２とＬＥＤ駆動ドライバ２３によりＬＥＤ５ａとＬＥＤ５ｂの点灯デューティをそれぞれ個別に制御して、白基準板４に照射させて、このときの白基準板４の反射光のＣＣＤ１０の出力に基づいて、原稿Ｇを読み取る際のＬＥＤ５ａとＬＥＤ５ｂの点灯デューティ制御を行う。 Prior to reading the document G, the reading control circuit 21 moves the first traveling body and the second traveling body to a position where the white reference plate 4 is read, and the LED driving driver 22 and the LED driving driver 23 cause the LED 5a and The lighting duty of the LED 5b is individually controlled to irradiate the white reference plate 4, and based on the output of the CCD 10 of the reflected light of the white reference plate 4 at this time, the LED 5a and the LED 5b are turned on when the original G is read. Duty control is performed.

次に、本実施例の作用を説明する。本実施例のスキャナ１は、原稿Ｇの読み取りに先立って２つのＬＥＤ５ａとＬＥＤ５ｂを個別に光量調整する。 Next, the operation of this embodiment will be described. Prior to reading the original G, the scanner 1 of the present embodiment individually adjusts the light quantity of the two LEDs 5a and 5b.

すなわち、スキャナ１は、原稿Ｇの読み取りに先立って、図４に示すように、ＬＥＤ５ａ、５ｂのデューティ（ｄｕｔｙ）調整を開始し（ステップＳ１０１）、まず、走行体モータの駆動を制御して、スキャンラインが白基準板４に位置するように第１走行体と第２走行体を移動させる（ステップＳ１０２）。 That is, before reading the document G, the scanner 1 starts adjusting the duty of the LEDs 5a and 5b (step S101) as shown in FIG. The first traveling body and the second traveling body are moved so that the scan line is positioned on the white reference plate 4 (step S102).

そして、読取制御回路２１が、ＬＥＤ５ａのデューティを所定光量である５０％に設定して、図５（ａ）及び図６に示すように、ＬＥＤ駆動ドライバ２２にＬＥＤ５ａを点灯駆動させ（ステップＳ１０３）、このＬＥＤ５ａを点灯させたときの白基準板４からの反射光をＣＣＤ１０に入射させてＣＣＤ１０で光電変換した白出力データ（ｄａｔａ１）をモニタする（ステップＳ１０４）。 Then, the reading control circuit 21 sets the duty of the LED 5a to a predetermined light amount of 50%, and causes the LED drive driver 22 to light up and drive the LED 5a as shown in FIGS. 5A and 6 (step S103). The reflected light from the white reference plate 4 when the LED 5a is turned on is incident on the CCD 10 and the white output data (data1) photoelectrically converted by the CCD 10 is monitored (step S104).

読取制御回路２１は、このＬＥＤ５ａのみ点灯させたときの白出力データ（ｄａｔａ１）に基づいて、２灯同時点灯時に最適な点灯デューティ（ｄｕｔｙ）を算出する（ステップＳ１０５）。 Based on the white output data (data1) when only the LED 5a is lit, the reading control circuit 21 calculates an optimal lighting duty (duty) when two lamps are lit simultaneously (step S105).

次に、読取制御回路２１は、ＬＥＤ５ｂのデューティを所定光量である５０％に設定して、図５（ｂ）及び図６に示すように、ＬＥＤ駆動ドライバ２３にＬＥＤ５ｂを点灯駆動させ（ステップＳ１０６）、このＬＥＤ５ｂを点灯させたときの白基準板４からの反射光をＣＣＤ１０に入射させてＣＣＤ１０で光電変換した白出力データ（ｄａｔａ２）をモニタする（ステップＳ１０７）。 Next, the reading control circuit 21 sets the duty of the LED 5b to a predetermined light amount of 50%, and causes the LED drive driver 23 to turn on the LED 5b as shown in FIGS. 5B and 6 (step S106). The reflected light from the white reference plate 4 when the LED 5b is turned on is incident on the CCD 10 and the white output data (data2) photoelectrically converted by the CCD 10 is monitored (step S107).

読取制御回路２１は、このＬＥＤ５ｂのみ点灯させたときの白出力データ（ｄａｔａ２）に基づいて、２灯同時点灯時に最適な点灯デューティ（ｄｕｔｙ）値を算出する（ステップＳ１０８）。 Based on the white output data (data2) when only the LED 5b is lit, the reading control circuit 21 calculates an optimum lighting duty (duty) value when two lamps are lit simultaneously (step S108).

スキャナ１は、このようにして２つのＬＥＤ５ａとＬＥＤ５ｂの光量（デューティ）を個別に調整すると、通常の読取動作を行って、まず、白基準板４を読み取ってシェーディング補正用の白基準データを取得した後、走行体モータをコンタクトガラス３の下方の原稿読取開始位置に移動させて、原稿Ｇの読取を開始する。このとき、読取制御回路２１は、図５（ｃ）及び図６に示すように、ＬＥＤ５ａとＬＥＤ５ｂを上記算出した点灯デューティ値で点灯させる。 When the light quantity (duty) of the two LEDs 5a and 5b is individually adjusted in this way, the scanner 1 performs a normal reading operation and first reads the white reference plate 4 to obtain white reference data for shading correction. After that, the traveling body motor is moved to the original reading start position below the contact glass 3 to start reading the original G. At this time, the reading control circuit 21 turns on the LEDs 5a and 5b with the calculated lighting duty value as shown in FIGS.

このように、本実施例のスキャナ１は、相対向して配置された２灯のＬＥＤ５ａ、５ｂから原稿Ｇに光を照射して当該原稿Ｇからの反射光をＣＣＤ１０に導入してＣＣＤ１０が入射光を光電変換することで当該原稿Ｇを読み取るに際して、読取部制御回路２１が、原稿Ｇの読取前に、２灯のそれぞれのＬＥＤ５ａ、５ｂをＬＥＤ駆動ドライバ２２、２３に独立して所定光量である５０％デューティで順次点灯させて、各ＬＣＤ５ａ、５ｂを独立して順次点灯させたときの白基準板４からの反射光のＣＣＤ１０の光電変換量に基づいて、原稿読取時の２灯のＬＥＤ５ａ、５ｂを同時に点灯させたときの設定光量を各ＬＣＤ５ａ、５ｂ毎に、ＬＥＤ駆動ドライバ２２、２３に設定し、当該原稿の読取時に、ＬＥＤ駆動ドライバ２２、２３が、当該設定光量で２灯のＬＥＤ５ａ、５ｂをそれぞれ点灯駆動させている。 As described above, in the scanner 1 of this embodiment, the original G is irradiated with light from the two LEDs 5a and 5b arranged opposite to each other, and the reflected light from the original G is introduced into the CCD 10 so that the CCD 10 enters. When the original G is read by photoelectrically converting light, the reading unit control circuit 21 sets the two LEDs 5a and 5b to a predetermined light amount independently of the LED driving drivers 22 and 23 before reading the original G. Based on the photoelectric conversion amount of the CCD 10 of the reflected light from the white reference plate 4 when the LCDs 5a and 5b are sequentially turned on sequentially with a certain 50% duty, the two LEDs 5a at the time of document reading 5b is set to the LED drive drivers 22 and 23 for each of the LCDs 5a and 5b, and when reading the original, the LED drive drivers 22 and 23 LED5a of 2 light at a constant light intensity, respectively lit driven 5b.

したがって、適正な光量を各ＬＥＤ５ａ、５ｂに対して設定して点灯して、２灯同時点灯時においても、十分なＣＣＤ１０の出力レベルを得ることができるとともに、Ｓ／Ｎをも向上させることができ、読取画像の画像品質を向上させることができる。 Therefore, it is possible to set an appropriate light amount for each LED 5a, 5b and light up, and to obtain a sufficient output level of the CCD 10 and improve the S / N even when the two lights are turned on simultaneously. And the image quality of the read image can be improved.

図７〜図９は、本発明の画像読取装置の第２実施例を示す図であり、本実施例は、請求項２に対応するものである。 FIGS. 7 to 9 are views showing a second embodiment of the image reading apparatus of the present invention. This embodiment corresponds to claim 2.

なお、本実施例は、上記第１実施例のスキャナ１と同様のスキャナに適用したものであり、本実施例の説明においては、必要に応じて、上記第１実施例の説明で用いた符号をそのまま用いて説明する。 This embodiment is applied to a scanner similar to the scanner 1 of the first embodiment. In the description of the present embodiment, the reference numerals used in the description of the first embodiment are used as necessary. This will be described using

本実施例のスキャナ１は、２個の光源であるＬＥＤ５ａとＬＥＤ５ｂを原稿Ｇの読取前に個別に光量調整した後、同時点灯した結果に基づいて光量調整する。 The scanner 1 of this embodiment adjusts the amount of light based on the result of simultaneously lighting the LEDs 5a and 5b, which are the two light sources, before individually reading the original G.

すなわち、スキャナ１は、原稿Ｇの読取前に、図７に示すように、ＬＥＤ５ａ、５ｂのデューティ（ｄｕｔｙ）調整を開始し（ステップＳ２０１）、まず、走行体モータの駆動を制御して、スキャンラインが白基準板４に位置するように第１走行体と第２走行体を移動させる（ステップＳ２０２）。 That is, before reading the document G, the scanner 1 starts adjusting the duty of the LEDs 5a and 5b as shown in FIG. 7 (step S201), and first controls the driving of the traveling body motor to scan. The first traveling body and the second traveling body are moved so that the line is positioned on the white reference plate 4 (step S202).

そして、読取制御回路２１が、ＬＥＤ５ａのデューティを所定光量である５０％に設定して、図７に示すように、ＬＥＤ駆動ドライバ２２にＬＥＤ５ａを点灯駆動させ（ステップＳ２０３）、このＬＥＤ５ａを点灯させたときの白基準板４からの反射光をＣＣＤ１０に入射させてＣＣＤ１０で光電変換した白出力データ（ｄａｔａ１）をモニタする（ステップＳ２０４）。 Then, the reading control circuit 21 sets the duty of the LED 5a to a predetermined light amount of 50%, and as shown in FIG. 7, causes the LED drive driver 22 to turn on the LED 5a (step S203), and turns on the LED 5a. Then, the reflected light from the white reference plate 4 is incident on the CCD 10 and the white output data (data1) photoelectrically converted by the CCD 10 is monitored (step S204).

読取制御回路２１は、このＬＥＤ５ａのみ点灯させたときの白出力データ（ｄａｔａ１）に基づいて、２灯同時点灯時に最適な点灯デューティ（ｄｕｔｙ）を算出する（ステップＳ２０５）。 Based on the white output data (data1) when only the LED 5a is lit, the reading control circuit 21 calculates an optimum lighting duty (duty) when two lamps are lit simultaneously (step S205).

次に、読取制御回路２１は、ＬＥＤ５ｂのデューティを所定光量である５０％に設定して、図７に示すように、ＬＥＤ駆動ドライバ２３にＬＥＤ５ｂを点灯駆動させ（ステップＳ２０６）、このＬＥＤ５ｂを点灯させたときの白基準板４からの反射光をＣＣＤ１０に入射させてＣＣＤ１０で光電変換した白出力データ（ｄａｔａ２）をモニタする（ステップＳ２０７）。 Next, the reading control circuit 21 sets the duty of the LED 5b to a predetermined light amount of 50%, and causes the LED drive driver 23 to turn on and drive the LED 5b as shown in FIG. 7 (step S206). The reflected light from the white reference plate 4 at this time is incident on the CCD 10 and the white output data (data 2) photoelectrically converted by the CCD 10 is monitored (step S207).

読取制御回路２１は、このＬＥＤ５ｂのみ点灯させたときの白出力データ（ｄａｔａ２）に基づいて、２灯同時点灯時に最適な点灯デューティ（ｄｕｔｙ）値を算出する（ステップＳ２０８）。 Based on the white output data (data 2) when only the LED 5b is lit, the reading control circuit 21 calculates an optimal lighting duty (duty) value when two lamps are lit simultaneously (step S208).

このようにして２つのＬＥＤ５ａとＬＥＤ５ｂの光量（デューティ）を個別に調整すると、読取制御回路２１は、２個のＬＥＤ５ａ、５ｂを同時点灯させた状態での光量調整を開始し（ステップＳ２０９）、上記ＬＥＤ５ａとＬＥＤ５ｂを個別に調整して算出した最適なデューティ値で同時点灯させる（ステップＳ２１０）。 When the light amounts (duties) of the two LEDs 5a and 5b are individually adjusted in this way, the reading control circuit 21 starts light amount adjustment in a state where the two LEDs 5a and 5b are turned on simultaneously (step S209). The LED 5a and the LED 5b are individually lit at the optimum duty value calculated by adjusting them individually (step S210).

次に、読取制御回路２１は、図８及び図９に示すように、このＬＥＤ５ａとＬＥＤ５ｂを同時点灯させたときの白基準板４からの反射光をＣＣＤ１０に入射させてＣＣＤ１０で光電変換した白出力データ（ｄａｔａ３）をモニタし（ステップＳ２１１）、モニタした白出力データ（ｄａｔａ３）に基づいて各ＬＥＤ５ａ、５ｂの最適な最終点灯デューティ（ｄｕｔｙ）を算出する（ステップＳ２１２）。 Next, as shown in FIGS. 8 and 9, the reading control circuit 21 causes the reflected light from the white reference plate 4 when the LEDs 5 a and 5 b are simultaneously turned on to enter the CCD 10 and photoelectrically convert it by the CCD 10. The output data (data 3) is monitored (step S211), and the optimum final lighting duty (duty) of each LED 5a, 5b is calculated based on the monitored white output data (data 3) (step S212).

すなわち、通常、２灯構成において若干出力が上がる傾向になるので、ＬＥＤ５ａ、５ｂの２灯点灯時のＣＣＤ出力データ（ｄａｔａ３）をモニタし、２灯点灯時の最適な出力が得られるよう制御する。例えば、目標とするＣＣＤ１０の出力レベルより１０％高い場合は、各ＬＥＤ５ａ、５ｂのデューティ（ｄｕｔｙ）値を―５％下げるように算出する。具体的には、ＬＥＤ５ａのデューティ（ｄｕｔｙ）：５０％の場合は、５０％＊０．９５＝４７．５％）とする。 In other words, since the output tends to increase slightly in the two-light configuration, the CCD output data (data 3) when the two lights of the LEDs 5a and 5b are lit is monitored and controlled so as to obtain the optimum output when the two lights are lit. . For example, when the output level of the target CCD 10 is 10% higher, the duty values of the LEDs 5a and 5b are calculated to be decreased by -5%. Specifically, when the duty of the LED 5a is 50%, 50% * 0.95 = 47.5%).

スキャナ１は、このようにして２つのＬＥＤ５ａとＬＥＤ５ｂの光量（デューティ）を個別に調整した後総合して調整すると、通常の読取動作を行って、まず、白基準板４を読み取ってシェーディング補正用の白基準データを取得した後、走行体モータをコンタクトガラス３の下方の原稿読取開始位置に移動させて、原稿Ｇの読取を開始する。このとき、読取制御回路２１は、図８に原稿読取時のデータとして示し、図９に光量調整後全体白波形として示すように、ＬＥＤ５ａとＬＥＤ５ｂを上記算出した最終点灯デューティ値で点灯させる。 When the scanner 1 adjusts the light amounts (duties) of the two LEDs 5a and 5b individually as described above, the scanner 1 performs a normal reading operation and first reads the white reference plate 4 for shading correction. After the white reference data is acquired, the traveling body motor is moved to the original reading start position below the contact glass 3 to start reading the original G. At this time, the reading control circuit 21 turns on the LEDs 5a and 5b with the calculated final lighting duty value as shown in FIG. 8 as data at the time of document reading and as shown in FIG.

このように、本実施例のスキャナ１は、読取部制御回路２１が、２灯のＬＥＤ５ａ、５ｂをそれぞれ独立して点灯させてＬＥＤ駆動ドライバ２２、２３に設定光量を設定した後、ＬＥＤ駆動ドライバ２２、２３に２灯のＬＥＤ５ａ、５ｂを当該設定光量で同時に点灯させ、当該２灯のＬＥＤ５ａ、５ｂを同時に点灯させたときのＣＣＤ１０の光電変換量に基づいて、ＬＥＤ駆動ドライバ２２、２３の各ＬＥＤ５ａ、５ｂの設定光量を補正し、原稿Ｇの読取時に、ＬＥＤ駆動ドライバ２２、２３が、補正後の設定光量で２灯のＬＥＤ５ａ、５ｂをそれぞれ点灯駆動させている。 As described above, in the scanner 1 of this embodiment, the reading unit control circuit 21 turns on the two LEDs 5a and 5b independently and sets the set light amounts in the LED drive drivers 22 and 23, and then the LED drive driver. Based on the photoelectric conversion amount of the CCD 10 when the two LEDs 5a and 5b are turned on simultaneously with the set light amount, and the two LEDs 5a and 5b are turned on simultaneously. The set light amounts of the LEDs 5a and 5b are corrected, and when the original G is read, the LED drive drivers 22 and 23 drive and drive the two LEDs 5a and 5b with the corrected set light amounts.

したがって、より一層適正な光量を各ＬＥＤ５ａ、５ｂに対して設定して点灯して、２灯同時点灯時においても、より一層適切なＣＣＤ１０の出力レベルを得ることができるとともに、Ｓ／Ｎをもより一層向上させることができ、読取画像の画像品質をより一層向上させることができる。 Therefore, it is possible to set a more appropriate light amount for each LED 5a, 5b and light up, and to obtain a more appropriate output level of the CCD 10 even when two lights are turned on at the same time. The image quality of the read image can be further improved.

図１０〜図１２は、本発明の画像読取装置の第３実施例を示す図であり、本実施例は、請求項３に対応するものである。 10 to 12 are views showing a third embodiment of the image reading apparatus of the present invention, and this embodiment corresponds to claim 3.

本実施例のスキャナ１は、２個の光源であるＬＥＤ５ａとＬＥＤ５ｂのうちのいずれか一方のみを原稿Ｇの読取前に光量調整した後、当該調整結果を基に、同時点灯して光量調整する。 The scanner 1 of this embodiment adjusts the light amount of only one of the two light sources, LED 5a and LED 5b, before reading the original G, and then lights up simultaneously to adjust the light amount based on the adjustment result. .

すなわち、スキャナ１は、原稿Ｇの読取前に、図１０に示すように、ＬＥＤ５ａ、５ｂのデューティ（ｄｕｔｙ）調整を開始し（ステップＳ３０１）、まず、走行体モータの駆動を制御して、スキャンラインが白基準板４に位置するように第１走行体と第２走行体を移動させる（ステップＳ３０２）。 That is, before reading the document G, the scanner 1 starts the duty adjustment of the LEDs 5a and 5b as shown in FIG. 10 (step S301), and first controls the driving of the traveling body motor to scan. The first traveling body and the second traveling body are moved so that the line is positioned on the white reference plate 4 (step S302).

そして、読取制御回路２１が、ＬＥＤ５ａのデューティを所定光量である５０％に設定して、図１１に示すように、ＬＥＤ駆動ドライバ２２にＬＥＤ５ａを点灯駆動させ（ステップＳ３０３）、図１２に破線で示すように、このＬＥＤ５ａを点灯させたときの白基準板４からの反射光をＣＣＤ１０に入射させてＣＣＤ１０で光電変換した白出力データ（ｄａｔａ１）をモニタする（ステップＳ３０４）。 Then, the reading control circuit 21 sets the duty of the LED 5a to a predetermined light amount of 50%, and as shown in FIG. 11, causes the LED drive driver 22 to turn on the LED 5a (step S303), and in FIG. As shown, the reflected light from the white reference plate 4 when the LED 5a is turned on is incident on the CCD 10 and the white output data (data1) photoelectrically converted by the CCD 10 is monitored (step S304).

読取制御回路２１は、このＬＥＤ５ａのみ点灯させたときの白出力データ（ｄａｔａ１）に基づいて、２灯同時点灯時に最適な点灯デューティ（ｄｕｔｙ）を算出する（ステップＳ３０５）。 Based on the white output data (data1) when only the LED 5a is lit, the reading control circuit 21 calculates an optimal lighting duty (duty) when two lamps are lit simultaneously (step S305).

次に、読取制御回路２１は、図１１に示すように、ＬＥＤ５ａについては、上記ステップＳ３０５で算出した最適な点灯デューティ（ｄｕｔｙ）を設定して、ＬＥＤ駆動ドライバ２２にＬＥＤ５ａを点灯駆動させ、ＬＥＤ５ｂについては、ＬＥＤ５ｂのデューティを５０％に設定して、ＬＥＤ駆動ドライバ２３にＬＥＤ５ｂを点灯駆動させ（ステップＳ３０６）、図１２に実線で示すように、ＬＥＤ５ａ及びＬＥＤ５ｂを点灯させたときの白基準板４からの反射光をＣＣＤ１０に入射させてＣＣＤ１０で光電変換した白出力データ（ｄａｔａ３）をモニタする（ステップＳ３０７）。 Next, as shown in FIG. 11, the reading control circuit 21 sets the optimum lighting duty (duty) calculated in step S305 for the LED 5a, causes the LED driving driver 22 to drive the LED 5a to turn on the LED 5b. , The duty of the LED 5b is set to 50%, the LED drive driver 23 is driven to turn on the LED 5b (step S306), and the white reference plate when the LED 5a and the LED 5b are turned on as shown by solid lines in FIG. The white output data (data 3) photoelectrically converted by the CCD 10 by making the reflected light from 4 incident on the CCD 10 is monitored (step S307).

読取制御回路２１は、このＬＥＤ５ａとＬＥＤ５ｂを点灯させたときの白出力データ（ｄａｔａ３）に基づいて、図１１に示すように、２灯同時点灯時に最適な点灯デューティ（ｄｕｔｙ）を算出する（ステップＳ３０８）。 Based on the white output data (data3) when the LEDs 5a and 5b are turned on, the reading control circuit 21 calculates an optimal lighting duty (duty) when two lamps are turned on simultaneously as shown in FIG. S308).

スキャナ１は、このようにして１つのＬＥＤ５ａの光量（デューティ）を個別に調整した後、２つのＬＥＤ５ａ、５ｂを点灯させて総合して光量（デューティ）を調整すると、通常の読取動作を行って、図１１に示すように、まず、白基準板４を読み取ってシェーディング補正用の白基準データを取得した後、走行体モータをコンタクトガラス３の下方の原稿読取開始位置に移動させて、原稿Ｇの読取を開始する。 After the scanner 1 individually adjusts the light quantity (duty) of one LED 5a in this way, the two LEDs 5a and 5b are turned on to adjust the light quantity (duty) as a whole and perform a normal reading operation. 11, first, after reading the white reference plate 4 to obtain white reference data for shading correction, the traveling body motor is moved to the original reading start position below the contact glass 3, and the original G Start reading.

このように、本実施例のスキャナ１は、読取部制御回路２１が、原稿Ｇの読取前に、２灯のＬＥＤ５ａ、５ｂのうちのいずれか１灯のＬＥＤ５ａ、５ｂをＬＥＤ駆動ドライバ２２、２３に所定光量で点灯させて、当該１灯のＬＥＤ５ａ、５ｂを点灯させたときの白基準板４からの反射光のＣＣＤ１０の光電変換量に基づいて、原稿読取時の２灯のＬＥＤ５ａ、５ｂを同時に点灯させたときの設定光量を各ＬＥＤ５ａ、５ｂ毎に、ＬＥＤ駆動ドライバ２２、２３に設定し、原稿Ｇの読取時に、ＬＥＤ駆動ドライバ２２、２３が、設定光量で２灯のＬＥＤ５ａ、５ｂをそれぞれ点灯駆動させている。 As described above, in the scanner 1 of this embodiment, before the reading of the document G, the reading unit control circuit 21 sets one of the two LEDs 5a and 5b to the LED driving drivers 22 and 23. The two LEDs 5a and 5b at the time of document reading are turned on based on the photoelectric conversion amount of the CCD 10 of the reflected light from the white reference plate 4 when the one LED 5a and 5b is turned on. The set amount of light when the LEDs are turned on at the same time is set in the LED drive drivers 22 and 23 for each of the LEDs 5a and 5b, and when reading the original G, the LED drive drivers 22 and 23 set the two LEDs 5a and 5b with the set amount of light. Each is driven to light.

したがって、少ないＬＥＤ５ａ、５ｂの点灯回数で、適正な光量を各ＬＥＤ５ａ、５ｂに対して設定して点灯して、２灯同時点灯時においても、十分なＣＣＤ１０の出力レベルを得ることができるとともに、簡単にＳ／Ｎをも向上させることができ、読取画像の画像品質を向上させることができる。 Therefore, with a small number of times the LEDs 5a and 5b are turned on, an appropriate amount of light is set for each LED 5a and 5b to turn on and a sufficient output level of the CCD 10 can be obtained even when the two lights are turned on simultaneously. The S / N can be easily improved and the image quality of the read image can be improved.

図１３及び図１４は、本発明の画像読取装置の第４実施例を示す図であり、本実施例は、請求項４及び請求項５に対応するものである。 FIGS. 13 and 14 are views showing a fourth embodiment of the image reading apparatus of the present invention. This embodiment corresponds to claims 4 and 5.

本実施例のスキャナ１は、２個の光源であるＬＥＤ５ａとＬＥＤ５ｂを原稿Ｇの読取前に個別に光量調整するとともに、異常判定を行って異常があると判定したＬＥＤ５ａまたはＬＥＤ５ｂの使用を中止する。 The scanner 1 according to the present embodiment individually adjusts the light amount of the two light sources LED 5a and LED 5b before reading the original G, and stops using the LED 5a or LED 5b determined to be abnormal by performing abnormality determination. .

すなわち、スキャナ１は、原稿Ｇの読取前に、図１３に示すように、ＬＥＤ５ａ、５ｂのデューティ（ｄｕｔｙ）調整を開始し（ステップＳ４０１）、まず、走行体モータの駆動を制御して、スキャンラインが白基準板４に位置するように第１走行体と第２走行体を移動させる（ステップＳ４０２）。 That is, before reading the document G, the scanner 1 starts adjusting the duty of the LEDs 5a and 5b (step S401) as shown in FIG. 13, and first controls the driving of the traveling body motor to scan. The first traveling body and the second traveling body are moved so that the line is positioned on the white reference plate 4 (step S402).

そして、読取制御回路２１が、ＬＥＤ５ａのデューティを所定光量である５０％に設定して、図７に示すように、ＬＥＤ駆動ドライバ２２にＬＥＤ５ａを点灯駆動させ（ステップＳ４０３）、このＬＥＤ５ａを点灯させたときの白基準板４からの反射光をＣＣＤ１０に入射させてＣＣＤ１０で光電変換した白出力データ（ｄａｔａ１）をモニタする（ステップＳ４０４）。 Then, the reading control circuit 21 sets the duty of the LED 5a to a predetermined light amount of 50%, and as shown in FIG. 7, causes the LED drive driver 22 to turn on the LED 5a (step S403), and turns on the LED 5a. The reflected light from the white reference plate 4 is incident on the CCD 10 and the white output data (data 1) photoelectrically converted by the CCD 10 is monitored (step S404).

読取制御回路２１は、モニタ結果に基づいてＣＣＤ１０の出力に異常が見られ、画像に影響があるかを判断する（ステップＳ４０５）。例えば、ＬＥＤ５ａのみを点灯したときに、図１４（ａ）に示すように、一部点灯不良やＬＥＤ５ａの一部光量ダウンにより、ＣＣＤ１０に出力低下があると、ＣＣＤ１０の出力に異常があり、画像に影響があると判断する。 Based on the monitor result, the reading control circuit 21 determines whether an abnormality is seen in the output of the CCD 10 and the image is affected (step S405). For example, when only the LED 5a is lit, as shown in FIG. 14A, if the output of the CCD 10 is reduced due to a partial lighting failure or a partial light quantity reduction of the LED 5a, the output of the CCD 10 is abnormal, and the image It is judged that there is an influence.

そして、読取制御回路２１は、ステップＳ４０５で、ＣＣＤ１０の出力に異常がなく、画像に影響がないと判断すると、このＬＥＤ５ａのみ点灯させたときの白出力データ（ｄａｔａ１）に基づいて、２灯同時点灯時に最適な点灯デューティ（ｄｕｔｙ）を算出し（ステップＳ４０６）、ＣＣＤ１０の出力に異常があり、画像に影響があると判断すると、ＬＥＤ５ａの使用を禁止（ＮＧ）とする（ステップＳ４０７）。 If the reading control circuit 21 determines in step S405 that there is no abnormality in the output of the CCD 10 and that there is no effect on the image, two reading lamps are simultaneously used based on the white output data (data1) when only the LED 5a is turned on. The optimal lighting duty (duty) at the time of lighting is calculated (step S406), and if it is determined that the output of the CCD 10 is abnormal and affects the image, the use of the LED 5a is prohibited (NG) (step S407).

次に、読取制御回路２１は、ＬＥＤ５ａを消灯させて、ＬＥＤ５ｂのデューティを所定光量である５０％に設定して、ＬＥＤ駆動ドライバ２３にＬＥＤ５ｂを点灯駆動させ（ステップＳ４０８）、このＬＥＤ５ｂを点灯させたときの白基準板４からの反射光をＣＣＤ１０に入射させてＣＣＤ１０で光電変換した白出力データ（ｄａｔａ２）をモニタする（ステップＳ４０９）。 Next, the reading control circuit 21 turns off the LED 5a, sets the duty of the LED 5b to a predetermined light amount of 50%, causes the LED drive driver 23 to drive the LED 5b to light (step S408), and turns on the LED 5b. The reflected light from the white reference plate 4 is incident on the CCD 10 and the white output data (data 2) photoelectrically converted by the CCD 10 is monitored (step S409).

読取制御回路２１は、モニタ結果に基づいてＣＣＤ１０の出力に異常が見られ、画像に影響があるかを判断する（ステップＳ４１０）。例えば、ＬＥＤ５ｂのみを点灯したときに、図１４（ｂ）に示すように、一部点灯不良やＬＥＤ５ａの一部光量ダウンがなく、ＣＣＤ１０に出力に低下がないと、ＣＣＤ１０の出力に異常がなく、画像に影響がないと判断する。 Based on the monitor result, the reading control circuit 21 determines whether an abnormality is seen in the output of the CCD 10 and the image is affected (step S410). For example, when only the LED 5b is lit, as shown in FIG. 14B, there is no partial lighting failure or partial light quantity reduction of the LED 5a, and there is no abnormality in the output of the CCD 10 if there is no drop in the output of the CCD 10. , It is determined that the image is not affected.

そして、読取制御回路２１は、ステップＳ４１０で、ＣＣＤ１０の出力に異常がなく、画像に影響がないと判断すると、このＬＥＤ５ｂのみ点灯させたときの白出力データ（ｄａｔａ２）に基づいて、２灯同時点灯時に最適な点灯デューティ（ｄｕｔｙ）を算出し（ステップＳ４１１）、ＣＣＤ１０の出力に異常があり、画像に影響があると判断すると、ＬＥＤ５ｂの使用を禁止（ＮＧ）とする（ステップＳ４１２）。 If the reading control circuit 21 determines in step S410 that there is no abnormality in the output of the CCD 10 and that there is no effect on the image, two readings are simultaneously made based on the white output data (data2) when only the LED 5b is turned on. The optimal lighting duty (duty) at the time of lighting is calculated (step S411). If it is determined that the output of the CCD 10 is abnormal and the image is affected, the use of the LED 5b is prohibited (NG) (step S412).

次に、読取制御回路２１は、ＬＥＤ５ｂのデューティを５０％に設定して、図７に示すように、ＬＥＤ駆動ドライバ２３にＬＥＤ５ｂを点灯駆動させ（ステップＳ２０６）、このＬＥＤ５ｂを点灯させたときの白基準板４からの反射光をＣＣＤ１０に入射させてＣＣＤ１０で光電変換した白出力データ（ｄａｔａ２）をモニタする（ステップＳ２０７）。 Next, the reading control circuit 21 sets the duty of the LED 5b to 50%, and as shown in FIG. 7, causes the LED drive driver 23 to turn on the LED 5b (step S206), and turns on the LED 5b. Reflected light from the white reference plate 4 is incident on the CCD 10 and the white output data (data 2) photoelectrically converted by the CCD 10 is monitored (step S207).

このようにして２つのＬＥＤ５ａとＬＥＤ５ｂに異常がないときには、読取制御回路２１は、上記設定したデューティ（ｄｕｔｙ）値でＬＥＤ５ａ、５ｂを同時に点灯させて原稿の読み取りを行う。 When there is no abnormality in the two LEDs 5a and 5b as described above, the reading control circuit 21 reads the document by simultaneously turning on the LEDs 5a and 5b with the set duty value.

また、読取制御回路２１は、上記処理で、ＬＥＤ５ａとＬＥＤ５ｂのいずれかに異常があり、使用を禁止していると、上記設定したデューティ（ｄｕｔｙ）値を１つのＬＥＤ５ａまたはＬＥＤ５ｂを点灯させたときに最適となる点灯デューティ（ｄｕｔｙ）に算出しなおして、当該算出しなおした点灯デューティ（ｄｕｔｙ）値でＬＥＤ５ａまたはＬＥＤ５ｂを点灯させて、原稿の読み取りを行う。 In addition, the reading control circuit 21 turns on one LED 5a or LED 5b with the set duty value when either of the LED 5a and the LED 5b is abnormal in the above processing and the use is prohibited. The lighting duty (duty) that is optimal for the above is calculated again, the LED 5a or LED 5b is turned on with the calculated lighting duty (duty) value, and the original is read.

このように、本実施の形態のスキャナ１は、読取部制御回路２１が、２灯のＬＥＤ５ａ、５ｂをそれぞれＬＥＤ駆動ドライバ２２、２３に独立して所定光量で順次点灯させたときのＣＣＤ１０の出力光量に基づいて、ＬＥＤ５ａ、５ｂの不点灯、ＬＥＤ５ａ、５ｂの主走査方向の一部分の光量不足等の光源異常現象の有無を検出して、当該光源異常現象から読取画像に異常画像が発生するか否かを判断し、当該異常画像が発生すると判断すると、当該異常現象のあるＬＥＤ５ａ、５ｂの点灯を消灯させるものとして、ＬＥＤ駆動ドライバ２２、２３に設定するとともに、原稿読取時の他のＬＥＤ５ａ、５ｂの設定光量をＬＥＤ駆動ドライバ２２、２３に設定し、ＬＥＤ駆動ドライバ２２、２３が、原稿読取時に、消灯の指示されたＬＥＤ５ａ、５ｂの点灯を消灯させるとともに、他のＬＥＤ５ａ、５ｂを設定光量で点灯駆動させている。 As described above, in the scanner 1 of the present embodiment, the output of the CCD 10 when the reading unit control circuit 21 sequentially turns on the two LEDs 5a and 5b independently of the LED drive drivers 22 and 23 with a predetermined light amount. Based on the amount of light, whether or not there is an abnormal light source phenomenon such as non-lighting of the LEDs 5a and 5b and insufficient light amount in a part of the LEDs 5a and 5b in the main scanning direction, and whether an abnormal image occurs in the read image from the abnormal light source phenomenon If it is determined that the abnormal image is generated, the LEDs 5a and 5b having the abnormal phenomenon are turned off to be set in the LED drive drivers 22 and 23, and the other LEDs 5a and 5b is set in the LED drive drivers 22 and 23, and the LED drive drivers 22 and 23 are instructed to turn off the LED 5a when reading the document. Together turns off the lighting of 5b, the other LED 5a, and 5b lighting was driven by setting light amount.

したがって、ＬＥＤ５ａ、５ｂに異常がある場合にも、適正な光量をＬＥＤ５ａ、５ｂに対して設定して点灯して、十分なＣＣＤ１０の出力レベルを得ることができるとともに、簡単にＳ／Ｎをも向上させることができ、読取画像の画像品質を向上させることができる。 Therefore, even when there is an abnormality in the LEDs 5a and 5b, it is possible to obtain a sufficient output level of the CCD 10 by setting an appropriate amount of light for the LEDs 5a and 5b, and to easily obtain an S / N. The image quality of the read image can be improved.

なお、読取制御回路２１は、上記処理で、ＬＥＤ５ａとＬＥＤ５ｂのいずれかに異常があり、使用を禁止している場合、図１５に示すように、本来の１灯分の目標光量よりも高めに再設定し、原稿Ｇを読み取らせるようにしてもよい。 When the reading control circuit 21 has an abnormality in either the LED 5a or the LED 5b in the above process and prohibits the use, as shown in FIG. 15, the reading control circuit 21 is set higher than the original target light amount for one lamp. It may be reset so that the original G is read.

このようにすると、Ｓ／Ｎをより一層向上させることができ、読取画像の画像品質を向上させることができる。 In this way, the S / N can be further improved, and the image quality of the read image can be improved.

以上、本発明者によってなされた発明を好適な実施例に基づき具体的に説明したが、本発明は上記のものに限定されるものではなく、その要旨を逸脱しない範囲で種々変更可能であることはいうまでもない。 The invention made by the present inventor has been specifically described based on the preferred embodiments. However, the present invention is not limited to the above, and various modifications can be made without departing from the scope of the invention. Needless to say.

２灯以上の原稿をのこう量調整を適切に行って画像読取を行うファクシミリ装置、複写装置、スキャナ等に適用することができる。 The present invention can be applied to a facsimile apparatus, a copying apparatus, a scanner, and the like that perform image reading by appropriately adjusting the amount of the two or more originals.

本発明の画像読取装置の第１実施例を適用したスキャナの正面概略構成図。1 is a schematic front configuration diagram of a scanner to which a first embodiment of an image reading apparatus of the present invention is applied. FIG. 図１の光源部分の拡大正面図。The enlarged front view of the light source part of FIG. 図１のスキャナの読取制御部とＣＣＤ基板のブロック構成図。FIG. 2 is a block configuration diagram of a reading control unit and a CCD substrate of the scanner in FIG. 1. 図１のスキャナによるＬＥＤの光量調整処理を示すフローチャート。2 is a flowchart showing LED light amount adjustment processing by the scanner of FIG. 1. 図４のＬＥＤの光量調整処理で２個のＬＥＤを個別に点灯した場合（ａ）、（ｂ）と２個のＬＥＤを同時点灯した場合の出力の一例を示す図。The figure which shows an example of the output at the time of lighting two LEDs individually (a) and (b) when two LEDs are individually lit in the LED light amount adjustment processing of FIG. 図４のＬＥＤの光量調整処理でのＬＥＤの点灯制御タイミングと出力データの関係を示す図。The figure which shows the relationship between LED lighting control timing in the light quantity adjustment process of LED of FIG. 4, and output data. 本発明の画像読取装置の第２実施例を適用したスキャナによるＬＥＤの光量調整処理を示すフローチャート。7 is a flowchart showing LED light amount adjustment processing by a scanner to which a second embodiment of the image reading apparatus of the invention is applied. 図７のＬＥＤの光量調整処理でのＬＥＤの点灯制御タイミングと出力データの関係を示す図。The figure which shows the lighting control timing of LED in the light quantity adjustment process of LED of FIG. 7, and the relationship between output data. 図７のＬＥＤの光量調整処理で２個のＬＥＤの同時点灯時の光量調整前後の出力を示す図。The figure which shows the output before and after the light quantity adjustment at the time of 2 LED simultaneous lighting by the light quantity adjustment process of LED of FIG. 本発明の画像読取装置の第３実施例を適用したスキャナによるＬＥＤの光量調整処理を示すフローチャート。10 is a flowchart showing LED light amount adjustment processing by a scanner to which a third embodiment of the image reading apparatus of the invention is applied. 図１０のＬＥＤの光量調整処理でのＬＥＤの点灯制御タイミングと出力データの関係を示す図。FIG. 11 is a diagram showing a relationship between LED lighting control timing and output data in the LED light amount adjustment processing of FIG. 10. 図１０のＬＥＤの光量調整処理で２個のＬＥＤの同時点灯時の出力と１個のＬＥＤのみの点灯時の出力を示す図。The figure which shows the output at the time of lighting of two LEDs simultaneously, and the output at the time of lighting of only one LED by the light quantity adjustment process of LED of FIG. 本発明の画像読取装置の第４実施例を適用したスキャナによるＬＥＤの光量調整処理を示すフローチャート。10 is a flowchart showing LED light amount adjustment processing by a scanner to which a fourth embodiment of the image reading apparatus of the invention is applied. 図１３のＬＥＤの光量調整処理で一部点灯不良のあるＬＥＤの出力（ａ）と正常ＬＥＤの出力（ｂ）の一例を示す図。The figure which shows an example of the output (a) of LED with a partial lighting failure by the light quantity adjustment process of LED of FIG. 13, and the output (b) of a normal LED. 図１３のＬＥＤの光量調整処理で１個の正常なＬＥＤで読み取りを行う場合の出力の説明図。Explanatory drawing of the output in the case of reading with one normal LED by the light quantity adjustment process of LED of FIG.

符号の説明Explanation of symbols

１スキャナ
２本体筐体
３コンタクトガラス
４白基準板
５光源
５ａ、５ｂＬＥＤ
６第１ミラー
７第２ミラー
８第３ミラー
９レンズ
１０ＣＣＤ
１１露光走査光学系
１２ＣＣＤ基板
２０読取制御部
２１読取制御回路
２２、２３ＬＥＤ駆動ドライバ
２４ＬＥＤ電源部
Ｇ原稿
DESCRIPTION OF SYMBOLS 1 Scanner 2 Main body housing 3 Contact glass 4 White reference board 5 Light source 5a, 5b LED
6 First mirror 7 Second mirror 8 Third mirror 9 Lens 10 CCD
DESCRIPTION OF SYMBOLS 11 Exposure scanning optical system 12 CCD board | substrate 20 Reading control part 21 Reading control circuit 22, 23 LED drive driver 24 LED power supply part G Original

Claims

相対向して配置された２灯の光源から原稿に光を照射して当該原稿からの反射光を光電変換手段に導入して当該光電変換手段が入射光を光電変換することで当該原稿を読み取る画像読取装置において、前記２灯の光源をそれぞれ独立して光量調整する光量調整手段と、前記原稿の読取前に、前記２灯のそれぞれの光源を前記光量調整手段に独立して所定光量で順次点灯させて、当該各光源を独立して順次点灯させたときの所定の基準部材からの反射光の前記光電変換手段の光電変換量に基づいて、前記原稿読取時の当該２灯の光源を同時に点灯させたときの設定光量を前記各光源毎に前記光量調整手段に設定する制御手段と、を備え、前記原稿の読取時に、前記光量調整手段が前記設定光量で前記２灯の光源をそれぞれ点灯駆動させることを特徴とする画像読取装置。 The original is read by irradiating the original with light from two light sources arranged opposite to each other, introducing reflected light from the original into the photoelectric conversion means, and the photoelectric conversion means photoelectrically converts the incident light. In the image reading apparatus, a light amount adjusting unit that independently adjusts the light amount of the two light sources and a light amount adjusting unit that sequentially adjusts the light sources of the two lights to a predetermined light amount independently of the light amount adjusting unit before reading the document. Based on the photoelectric conversion amount of the photoelectric conversion means of the reflected light from a predetermined reference member when each of the light sources is turned on independently and sequentially, the two light sources at the time of reading the document are simultaneously And a control means for setting the light quantity adjustment means for each light source in the light quantity adjustment means, and the light quantity adjustment means turns on the two light sources with the set light quantity when reading the document. To drive Image reading apparatus according to symptoms.

前記制御手段は、前記２灯の光源をそれぞれ独立して点灯させて前記光量調整手段に設定光量を設定した後、前記光量調整手段に前記２灯の光源を当該設定光量で同時に点灯させ、当該２灯の光源を同時に点灯させたときの前記光電変換手段の光電変換量に基づいて、前記光量調整手段の各光源の前記設定光量を補正し、前記原稿の読取時に、前記光量調整手段が前記補正後の設定光量で前記２灯の光源をそれぞれ点灯駆動させることを特徴とする請求項１記載の画像読取装置。 The control means turns on the two light sources independently and sets a set light quantity in the light quantity adjusting means, and then causes the light quantity adjustment means to simultaneously turn on the two light sources with the set light quantity, Based on the photoelectric conversion amount of the photoelectric conversion unit when the two light sources are turned on simultaneously, the set light amount of each light source of the light amount adjustment unit is corrected, and when the original is read, the light amount adjustment unit The image reading apparatus according to claim 1, wherein each of the two light sources is driven to turn on with the set light amount after correction.

相対向して配置された２灯の光源から原稿に光を照射して当該原稿からの反射光を光電変換手段に導入して当該光電変換手段が入射光を光電変換することで当該原稿を読み取る画像読取装置において、前記２灯の光源をそれぞれ独立して光量調整する光量調整手段と、前記原稿の読取前に、前記２灯の光源のうちのいずれか１灯の光源を前記光量調整手段に所定光量で点灯させて、当該１灯の光源を点灯させたときの所定の基準部材からの反射光の前記光電変換手段の光電変換量に基づいて、前記原稿読取時の当該２灯の光源を同時に点灯させたときの設定光量を前記各光源毎に前記光量調整手段に設定する制御手段と、を備え、前記原稿の読取時に、前記光量調整手段が前記設定光量で前記２灯の光源をそれぞれ点灯駆動させることを特徴とする画像読取装置。 The original is read by irradiating the original with light from two light sources arranged opposite to each other, introducing reflected light from the original into the photoelectric conversion means, and the photoelectric conversion means photoelectrically converts the incident light. In the image reading apparatus, a light amount adjusting unit that independently adjusts the light amount of each of the two light sources, and one of the two light sources is used as the light amount adjusting unit before reading the document. Based on the photoelectric conversion amount of the photoelectric conversion means of the reflected light from the predetermined reference member when the one light source is turned on with the predetermined light quantity, the two light sources at the time of reading the document are Control means for setting the light quantity adjustment means for each light source in the light quantity adjustment means, and when the original is read, the light quantity adjustment means sets the two light sources with the set light quantity. It is characterized by being driven to light Image reading apparatus for.

前記制御手段は、前記２灯の光源をそれぞれ前記光量調整手段に独立して所定光量で順次点灯させたときの前記光電変換手段の出力光量に基づいて、当該光源の不点灯、当該光源の主走査方向の一部分の光量不足等の光源異常現象の有無を検出して、当該光源異常現象から読取画像に異常画像が発生するか否かを判断し、当該異常画像が発生すると判断すると、当該異常現象のある光源の点灯を消灯させるものとして、前記光量調整手段に設定するとともに、前記原稿読取時の他の光源の設定光量を前記光量調整手段に設定し、前記光量調整手段が、原稿読取時に、前記消灯の指示された光源の点灯を消灯させるとともに、他の光源を前記設定光量で点灯駆動させることを特徴とする請求項１または請求項２記載の画像読取装置。 The control means is configured such that the light source is not turned on based on the output light quantity of the photoelectric conversion means when the two light sources are sequentially turned on with a predetermined light quantity independently of the light quantity adjusting means. By detecting the presence or absence of an abnormal light source phenomenon such as a lack of light in a part of the scanning direction, it is determined whether or not an abnormal image is generated in the read image from the abnormal light source phenomenon. The light source having a phenomenon is turned off to be set in the light amount adjustment unit, and the set light amount of another light source at the time of reading the document is set to the light amount adjustment unit. 3. The image reading apparatus according to claim 1, wherein the light source instructed to be turned off is turned off and another light source is driven to turn on with the set light amount.

前記制御手段は、前記点灯させる側の光源の前記設定光量を、本来の１灯分の目標光量よりも高めの光量に前記光量調整手段に設定することを特徴とする請求項４記載の画像読取装置。
5. The image reading device according to claim 4, wherein the control unit sets the set light amount of the light source on the lighting side to the light amount adjusting unit to a light amount higher than an original target light amount for one lamp. apparatus.