Image reading apparatus

Abstract

An image reading apparatus includes a line light source having a light guide plate and red-, green-, and blue-LEDs, for a light transmitting original, and a contact image sensor unit for detecting light from the line light source. The light transmitting original is arranged between the line light source and the contact image sensor unit. The light transmitting original is read by moving the line light source and the contact image sensor unit relative to the light transmitting original. The line light source is moved interlockingly with the contact image sensor unit by the attraction between a magnet provided at both ends of the line light source in the longitudinal direction thereof and a magnet provided at both ends of the contact image sensor unit in the longitudinal direction thereof.

What is claimed is:  
     
         1 . An image reading apparatus of a contact image sensor type for reading a light transmitting original by moving a contact image sensor unit on a guide rail, wherein a distance from an original surface of the light transmitting original to the contact image sensor unit is adjusted by changing a position of a surface of the guide rail on which the contact image sensor unit moves and, thus, a resolution is held.  
     
     
         2 . An image reading apparatus according to  claim 1 , wherein the distance from the original surface of the light transmitting original to the contact image sensor unit is adjusted by forming said guide rail to be rotatable and cam-shaped.  
     
     
         3 . An image reading apparatus of a contact image sensor type for reading a light transmitting original by moving a contact image sensor unit on a guide rail, wherein a distance from an original surface of the light transmitting original to the contact image sensor unit is adjusted by providing a lifting mechanism between said guide rail and the contact image sensor unit and, thus, a resolution is held.  
     
     
         4 . An image reading apparatus according to  claim 3 , wherein said lifting mechanism is a jack mechanism.  
     
     
         5 . An image reading apparatus according to  claim 1  or  3 , wherein the distance from the original surface of said light transmitting original to the contact image sensor unit is stepwise adjusted.  
     
     
         6 . An image reading apparatus comprising: 
 a first line-light-source for irradiating a light transmitting original; and    a line sensor for receiving transmission light from said light transmitting original irradiated by said first line-light-source,    wherein the light transmitting original is arranged between said first line-light-source and said line sensor, said first line-light-source and said line sensor are moved relative to the light transmitting original, and the light transmitting original is thus read.    
     
     
         7 . An image reading apparatus according to  claim 6 , wherein said first line-light-source and said line sensor comprise interlocking means for interlockingly moving said first line-light-source and said line sensor.  
     
     
         8 . An image reading apparatus according to  claim 7 , wherein said interlocking means comprises a magnet provided at both ends of said first line-light-source in the longitudinal direction thereof and a magnet provided at both ends of said line sensor in the longitudinal direction thereof, and interlockingly moves said first line-light-source and said line sensor by using attraction between said magnets.  
     
     
         9 . An image reading apparatus according to  claim 6 , further comprising 
 a second line-light-source for irradiating a sheet original,    wherein the sheet original can be read by receiving reflection light from said sheet original by said line sensor.    
     
     
         10 . An image reading apparatus according to  claim 9 , wherein upon reading the sheet original, said first line-light-source is not moved interlockingly with said line sensor.  
     
     
         11 . An image reading apparatus according to  claim 9 , further comprising 
 a shared light-on circuit for lighting on said first line-light-source and said second line-light-source,    wherein an output of said light-on circuit is supplied to said first line-light-source or said second line-lights source by changing over a switch.    
     
     
         12 . An image reading apparatus according to  claim 9 , wherein shading correction for the inhomogeneity of the light amount of said first line-light-source and the inhomogeneity of the sensitivity of said line sensor is one-dimensionally performed in the longitudinal direction of said first line-light-source, or shading correction for the inhomogeneity of the light amount of said second line-light-source and the inhomogeneity of the sensitivity of said line sensor is one-dimensionally performed in the longitudinal direction of said second line-light-source.  
     
     
         13 . An image reading apparatus of a contact image sensor type having a area light source, for reading a light transmitting original placed on an original base by irradiating light thereto from the area light source and receiving transmission light, 
 wherein said original base has an uneven portion on a front surface on the side on which the light transmitting original is placed without effect to optical characteristics for reading the light transmitting original so that the adhesion of the light transmitting original to said original base is prevented upon placing the light transmitting original on said original base.    
     
     
         14 . An image reading apparatus of a contact image sensor type having a area light source, for reading a light transmitting original placed on an original base by irradiating light thereto from the area light source and receiving transmission light, 
 wherein said original base has a projection having a periodic array on a front surface on the side on which the light transmitting original is placed without effect to optical characteristics for reading the light transmitting original so that the adhesion of the light transmitting original to said original base is prevented upon placing the light transmitting original on said original base.    
     
     
         15 . An image reading apparatus according to  claim 13  or  14 , further comprising 
 a line light source,  
 wherein a sheet original placed on said original base can be read by irradiating light to the sheet original from said line light source and by receiving reflection light.  
 
     
     
         16 . An image reading apparatus according to  claim 13  or  14 , wherein an average coarseness of a center line Ra of the original base having said the uneven portion or said projection having the periodic array formed on the surface thereof ranges  
       0.02 μm≦Ra≦1.0 μm.  
     
     
         17 . An image reading apparatus according to  claim 13  or  14 , wherein said original base is made of a glass plate.  
     
     
         18 . An image reading apparatus according to  claim 13  or  14 , wherein a scattering plate provided on the original base side of said area light source, for scattering light has an uneven portion without effect to optical characteristics for reading the original.  
     
     
         19 . An image reading apparatus comprising: 
 a line light source for emitting visible light and/or light other than the visible light and irradiating the light to an original; and    a line sensor having the sensitivity to the visible light and/or the light other than the visible light, for receiving reflection light from said original irradiated by said line light source,    wherein said original having information capable of being read by the visible light and/or the light other than the visible light is read by moving said line light source and said line sensor relative to said original, by irradiating the visible light and/or the light other than the visible light from said line light source except for when said line light source irradiates the visible light and said line sensor receives the visible light, and by receiving the visible light and/or the light other than the visible light by said line sensor.    
     
     
         20 . An image reading apparatus comprising: 
 a area light source for emitting visible light and/or light other than the visible light and irradiating the light to an original; and    a line sensor having the sensitivity to the visible light and/or the light other than the visible light, for receiving transmission light from said original irradiated by said area light source,    wherein said original having information capable of being read by the visible light and/or the light other than the visible light is read by moving said line sensor relative to said original, by irradiating the visible light and/or the light other than the visible light from said area light source except for when said area light source irradiates the visible light and said line sensor receives the visible light, and by receiving the visible light and/or the light other than the visible light by said line sensor.    
     
     
         21 . An image reading apparatus comprising: 
 a line light source for emitting visible light and/or light other than the visible light and irradiating the light to an original; and    a line sensor having the sensitivity to the visible light and/or the light other than the visible light, for receiving transmission light from said original irradiated by said line light source,    wherein said original having information capable of being read by the visible light and/or the light other than the visible light is read by moving said line light source and said line sensor relative to said original, by irradiating the visible light and/or the light other than the visible light from said line light source except for when said line light source irradiates the visible light and said line sensor receives the visible light, and by receiving the visible light and/or the light other than the visible light by said line sensor.    
     
     
         22 . An image reading apparatus comprising: 
 a line light source for emitting visible light and/or light other than the visible light and irradiating the light to an original; and    a line sensor having the sensitivity to the visible light and/or the light other than the visible light, for receiving transmission light from said original irradiated by said line light source,    wherein said original having information capable of being read by the visible light and/or the light other than the visible light is read by moving said original relative to said line light source and the line sensor, by irradiating the visible light and/or the light other than the visible light from said line light source except for when said line light source irradiates the visible light and said line sensor receives the visible light, and by receiving the visible light and/or the light other than the visible light by said line sensor.    
     
     
         23 . An image reading apparatus comprising: 
 a line light source for emitting visible light and/or light other than the visible light and irradiating the light to an original;    a area light source for emitting the visible light and/or the light other than the visible light and irradiating the light to the original; and    a line sensor having the sensitivity to the visible light and/or the light other than the visible light, for receiving reflection light from said original irradiated by said line light source and transmission light from said original irradiated by said area light source,    wherein said original having information capable of being read by the visible light and/or the light other than the visible light is read by switching and lighting on said line light source and said area light source, by moving said line light source and said line sensor relative to said original, by irradiating the visible light and/or the light other than the visible light from said line light source or said area light source except for when said line light source or said area light source irradiates the visible light and said line sensor receives the visible light, and by receiving the visible light and/or the light other than the visible light by said line sensor.    
     
     
         24 . An image reading apparatus comprising: 
 a first line-light-source for emitting visible light and/or light other than the visible light and irradiating the light to an original;    a second line-light-source for emitting the visible light and/or the light other than the visible light and irradiating the light to the original; and    a line sensor having the sensitivity to the visible light and/or the light other than the visible light, for receiving transmission light irradiated by said first line-light-source from said original and reflection light irradiated by said second line-light-source from said original,    wherein said original having information capable of being read by the visible light and/or the light other than the visible light is read by switching and lighting on said first line-light-source and said second line-light-source, by moving said first line-light-source, said second line-light-source, and said line sensor relative to said original, by irradiating the visible light and/or the light other than the visible light from said first line-light-source or said second line-light-source except for when said first line-light-source or said second line-light-source irradiates the visible light and said line sensor receives the visible light, and by receiving the visible light and/or the light other than the visible light by said line sensor.    
     
     
         25 . An image reading apparatus comprising: 
 a first line-light-source for emitting visible light and/or light other than the visible light and irradiating the light to an original;    a second line-light-source for emitting the visible light and/or the light other than the visible light and irradiating the light to the original; and    a line sensor having the sensitivity to the visible light and/or the light other than the visible light, for receiving transmission light from said original irradiated by said first line-light-source and reflection light from said original irradiated by said second line-light-source,    wherein said original having information capable of being read by the visible light and/or the light other than the visible light is read by switching and lighting on said first line-light-source and said second line-light-source, by moving said original relative to said first line-light-source, said second line-light-source, and said line sensor, by irradiating the visible light and/or the light other than the visible light from said first line-light-source or said second line-light-source except for when said first line-light-source or said second line-light-source irradiates the visible light and said line sensor receives the visible light, and by receiving the visible light and/or the light other than the visible light by said line sensor.    
     
     
         26 . An image reading apparatus according to  claims 19  to  25 , wherein the visible light is red (R) light, green (G) light, and blue (B) light, and the light other than the visible light is infrared light and/or ultraviolet light.