JP4089136B2 - Carriage and its adjustment method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a carriage and an adjustment method thereof, and more particularly to a carriage that can reciprocate in parallel with an original table on which an original is placed and an adjustment method thereof.
[0002]
[Prior art]
Conventionally, as an image reading apparatus for reading a document such as an image or a character, for example, a flat bed type image reading apparatus in which a document table made of a transparent plate such as glass is provided on an upper surface of a box-shaped housing is known. Yes. A carriage that moves in parallel with the document table by a driving device is provided inside the housing. A light source for a reflective document for reading an opaque document such as paper and a large number of photoelectric conversion elements are arranged on the carriage. Line sensor is installed. Irradiation light from the light source of the carriage is reflected on the surface of the original on the original table and is condensed on the line sensor by a condenser lens.
[0003]
When reading a document, the document placed on the document table is irradiated with light from a light source, the reflected light of the document surface is collected on a line sensor by a condenser lens, and the carriage is perpendicular to the arrangement direction of the elements of the line sensor. In addition, the contrast of the original is detected while being moved parallel to the original surface and converted into an electric signal. In such an image reading apparatus, in order to read a wide range of originals with high resolution by a small line sensor and to make the whole apparatus small, the reflected light of the original surface is further reflected by a plurality of mirrors provided on the carriage. In general, the optical path length is increased by guiding the light to a condensing lens.
[0004]
Recently, a light source is provided above the document table, and light transmitted from the light source and transmitted through the document is read by a line sensor of the carriage, whereby a transparent document such as a film can be read. In such an image reading apparatus for both a reflective original and a transparent original, it is common to add a light source for a transparent original to the image reading apparatus for a reflective original.
[0005]
[Problems to be solved by the invention]
However, in an image reading apparatus for both a reflective original and a transparent original, since a light source for a transparent original is generally mounted on the image reading apparatus for a reflective original, the magnification of the condenser lens of the carriage is adjusted to that of the reflective original. The resolution is set. In general, a transparent document has image information denser than that of a reflective document. Therefore, even when the image information of a reflective document is read at a resolution sufficient to reproduce, the image information of the transparent document is reproduced. The resolution may be insufficient. Therefore, in order to reproduce the image information of the transparent original, it is necessary to read the original with a higher resolution than when reproducing the image information of the reflective original.
[0006]
In order to read a transparent document at a higher resolution than a reflective document, two condensing lenses with different magnifications are provided in the carriage, and images with different magnifications are connected to the line sensor by switching the condensing lenses for condensing on the line sensor. It is possible to imagine. In this case, a transparent original is read using a high-magnification condensing lens, and a reflective original is read using a low-magnification condensing lens.
[0007]
However, in a carriage configured to switch between two condenser lenses having different magnifications, the imaging position of each condenser lens is different, so the imaging position of the light focused by both condenser lenses is maintained on the line sensor surface. It is difficult to do. For this reason, if the imaging position of the light focused by one condenser lens is maintained on the line sensor surface, the light focused by the other condenser lens cannot be maintained on the line sensor surface. there were.
[0008]
Furthermore, since the two condensing lenses having different magnifications have different optical path lengths, there is a problem that when the condensing lens for condensing light on the line sensor is switched, it is also necessary to switch the optical path length.
[0009]
The present invention has been made to solve the above-described problem, and provides a carriage that maintains an image formation position of light focused by a plurality of lenses having different magnifications on an optical sensor surface and an adjustment method thereof. Objective.
Another object of the present invention is to provide a carriage that reduces the physique by switching the optical path length with a simple structure and secures a mounting space, and an image reading apparatus including the carriage.
[0010]
[Means for Solving the Problems]
According to the carriage of the first aspect of the present invention, the first mirror that reflects the light reflected on the document surface or transmitted through the document, the first lens that collects the reflected light of the first mirror, and the document surface A second mirror that reflects the light reflected or transmitted through the document by an optical path different from that of the first mirror, and a second mirror that has a magnification different from that of the first lens and collects the reflected light of the second mirror. And a switching means for switching the lens condensing on the optical sensor to the first lens or the second lens, so that the first lens or the second lens having the higher magnification is used for transmission. The original can be read and the reflective original can be read using the lower magnification of the first lens or the second lens. Further, the position of the optical sensor relative to the housing is adjusted by the optical sensor adjusting means, and the lens focused on the optical sensor is switched to the first lens or the second lens by the switching means, and then the first lens is adjusted by the lens adjusting means. Alternatively, by adjusting the position of the second lens with respect to the housing, the imaging positions of both the light focused by the first lens and the light focused by the second lens can be maintained on the photosensor surface. Therefore, by forming a high-magnification transparent original image and a low-magnification reflective original image on the optical sensor surface, the transparent original can be read at a higher resolution than the reflective original.
[0011]
According to the carriage of the second aspect of the present invention, since the first mirror or the second mirror has the movable mirror movable by the housing, the first lens or the second lens is condensed by the switching means. When switching to the second lens, the optical path length can be easily switched with a simple structure by moving the movable mirror. Therefore, the size of the carriage can be reduced, and a mounting space can be easily secured.
[0012]
According to the carriage described in claim 3 of the present invention, one or both of the first lens and the second lens has the focus adjusting means for adjusting the focus of the light focused on the photosensor. The imaging position of one or both of the focused light and the focused light by the second lens can be maintained on the optical sensor surface with high accuracy.
[0013]
According to the image reading apparatus of the fourth aspect of the present invention, since the carriage according to the first, second or third aspect is provided, both the light focused by the first lens and the light focused by the second lens are provided. Can be maintained on the optical sensor surface. Therefore, a high-magnification transparent original image and a low-magnification reflective original image are imaged on the optical sensor surface to read the transparent original at a higher resolution than the reflective original and reduce the manufacturing cost with a simple structure. Can do.
[0014]
According to the carriage adjustment method of the fifth aspect of the present invention, the position of the optical sensor with respect to the housing is adjusted, the lens for condensing on the optical sensor is switched to the first lens or the second lens, and the first lens or Since the position of the second lens with respect to the housing is adjusted, the imaging positions of both the light focused by the first lens and the light focused by the second lens can be maintained on the photosensor surface. Therefore, by forming a high-magnification transparent original image and a low-magnification reflective original image on the optical sensor surface, the transparent original can be read at a higher resolution than the reflective original.
[0015]
According to the carriage adjustment method of the sixth aspect of the present invention, the focal point of the light focused on the photosensor of either the first lens or the second lens before adjusting the position of the photosensor relative to the housing. Therefore, the imaging position of the light focused by either the first lens or the second lens can be maintained on the optical sensor surface with high accuracy.
[0016]
According to the carriage adjustment method of the seventh aspect of the present invention, before adjusting the position of the first lens or the second lens with respect to the housing, the optical sensor of either the first lens or the second lens is adjusted. Since the focal point of the light focused on the light sensor is adjusted, the imaging position of the light focused on either the first lens or the second lens can be maintained on the optical sensor surface with high accuracy.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example showing an embodiment of the invention is described in detail based on a drawing.
1 to 7 show an embodiment in which the present invention is applied to a flat bed type image reading apparatus.
[0018]
As shown in FIGS. 5 and 7, a document table 3 made of a transparent plate such as glass is provided on the upper surface of the box-shaped housing 2. Inside the housing 2 is provided a carriage 6 that can reciprocate in parallel with the document 5 placed on the document table 3 by a driving device (not shown). Here, FIG. 5 shows a case where a reflective original is read, and FIG. 7 shows a case where a transparent original is read. In order to simplify the description, the document 5 described in this specification includes both a reflective document such as paper and a transparent document such as a positive film and a negative film.
[0019]
A light source 61 and a line sensor 62 as an optical sensor are mounted on the carriage 6. As shown in FIG. 5, when reading a reflective document, the light emitted from the light source 61 is reflected by the surface of the document 5, reflected by the movable mirror 63, mirrors 65, 64 and 66, and then condensed as the first lens. The light is condensed on the line sensor 62 by the lens 67. In the case of reading a reflective original, light from the original 5 is reflected in the order of the movable mirror 63, mirror 65, mirror 64, and mirror 66, and the light is reflected four times by the four mirrors, and the condenser lens from the original 5 is reflected. The optical path length up to 67 is increased. As shown in FIG. 7, when a transparent original is read, the irradiation light of the surface light source 68 passes through the original 5 and is reflected by the movable mirror 63 and the mirrors 64 and 66, and then a condenser lens 69 as a second lens. Thus, the light is condensed on the line sensor 62. When reading a transparent original, the light from the original 5 is reflected in the order of the movable mirror 63, the mirror 64, and the mirror 66, and the light is reflected three times by the three mirrors so that the light from the original 5 to the condenser lens 67 is reflected. An optical path is formed. A light source 61, a movable mirror 63, mirrors 64, 65 and 66, condenser lenses 67 and 69, and a line sensor 62 are accommodated in a housing 59. Here, the movable mirror 63 and the mirrors 65, 64, and 66 constitute a first mirror, and the movable mirror 63 and the mirrors 64 and 66 constitute a second mirror. Since the movable mirror 63 can be rotated around the mirror fulcrum 60, the optical path length can be switched between when the reflective original is read and when the transparent original is read.
[0020]
The light source 61 is provided perpendicular to the moving direction of the carriage 6, and a fluorescent lamp or the like is used. Further, the surface light source 68 is provided above the document table 3 and reflects light irradiated from a fluorescent lamp (not shown) to the unevenly spaced grooves carved on a light guide plate (not shown) to the document table 3 side. Irradiation as uniform light is possible.
[0021]
As the line sensor 62, a charge storage type optical sensor in which a plurality of pixels such as CCDs are linearly arranged perpendicular to the moving direction of the carriage 6 is used. A document guide 4 that positions the reading position of the document 5 and restricts the movement of the document 5 when the document is read is provided around the document table 3. A white reference 31 having a highly reflective uniform reflection surface is provided at the end of the document table 3 in the moving direction of the carriage 6.
In the line sensor 62, an amount of electric charge corresponding to the amount of light collected by each element is accumulated, and the accumulated electric charge is processed by the signal processing device 7.
[0022]
In FIG. 6, the A / D converter 11 converts data from the line sensor 62 input via the amplifier 10 into a digital signal and passes it to the shading correction unit 12. The shading correction unit 12 uses the white reference data obtained by reading the white reference 31 before the start of reading and the black reference data stored in advance, and the variation in sensitivity among the elements of the line sensor 62 and the main light source 61. The variation in the amount of light in the scanning direction is corrected. The gamma correction unit 13 performs gamma correction using a predetermined gamma function, and converts the light amount signal output from the shading correction unit 12 into an image signal. The other correction unit 14 performs various conversions such as color correction, edge enhancement, and area enlargement / reduction.
[0023]
The control unit 15 includes a microcomputer including a CPU, a RAM, a ROM, and the like. The control unit 15 controls the entire image reading apparatus 1 and is connected to an external image processing apparatus (not shown) such as a personal computer via the interface 8. .
[0024]
Next, the carriage 6 will be described in detail with reference to FIGS.
1 to 4 show the carriage 6 of the image reading apparatus of this embodiment. 1 and 3 are views of the carriage 6 as viewed from the document table 3 side, and FIGS. 2 and 4 are views of the carriage 6 as viewed from the side with respect to the moving direction. The arrow indicates the moving direction of the carriage 6. Here, FIGS. 1 and 2 show a case where a reflective original is read, and FIGS. 3 and 4 show a case where a transparent original is read.
[0025]
As shown in FIGS. 1 and 3, the condenser lens 67 and the condenser lens 69 are held by the main lens holder 20 and the sub lens holder 21, respectively, and the inside of the housing 59 is integrally formed in a direction perpendicular to the optical axis. It is movable. The condenser lens 69 has a magnification that is an integral multiple of the condenser lens 67, that is, a magnification different from that of the condenser lens 67. The main lens holder 20 has main bearings 22 and 23 and a sub bearing 24. The main bearings 22 and 23 are guided by the main guide shaft 90 and can slide on the main guide shaft 90, and the sub bearing 24 is guided by the sub guide shaft 25 and can slide on the sub guide shaft 25. The main lens holder 20 has a helical spline 20 a formed on the outer periphery, and the helical spline 20 a meshes with the gear 53. The gear 53 meshes with the worm wheel 52, and the worm wheel 52 meshes with the worm 51 of the motor 50 attached to the housing 59. The motor 50 is, for example, a stepping motor. When the motor 50 is energized, the driving force of the motor 50 can be transmitted to the main lens holder 20 via the worm 51, the worm wheel 52, the gear 53, and the helical spline 20a. Therefore, the condensing lens 67 and the condensing lens 69 can move smoothly and stably by the main bearings 22 and 23 and the sub bearing 24 being guided by the main guide shaft 90 and the sub guide shaft 25. Here, the worm 51, the worm wheel 52, the gear 53, the helical spline 20a, and the motor 50 constitute a switching means.
[0026]
The main lens holder 20 has a focus adjustment groove 91 as a focus adjustment means and a set screw 92 on the outer wall. The focus adjustment groove 91 is for adjusting the focus of the light focused on the line sensor 62. An adjustment pin (not shown) that matches the groove width of the focus adjustment groove 91 is inserted into the focus adjustment groove 91 to collect the light. By moving the optical lens 67 in a direction parallel to the optical axis, the imaging position of the light focused by the condenser lens 67 can be maintained on the sensor surface of the line sensor 62. Then, by fixing with the set screw 92, the position after the focus adjustment can be held.
[0027]
The sub lens holder 21 is provided in the main lens holder 20, and includes a focus adjustment groove 93 as a focus adjustment unit, a set screw 94, a lens tilt hole 95 as a lens adjustment unit, a fulcrum 96, and a screw 97. On the outer wall. The focus adjustment groove 93 is for adjusting the focus of the light focused on the line sensor 62. An adjustment pin (not shown) that matches the groove width of the focus adjustment groove 93 is inserted into the focus adjustment groove 93 to collect the light. By moving the optical lens 69 in a direction parallel to the optical axis, the imaging position of the light focused by the condenser lens 69 can be maintained on the sensor surface of the line sensor 62. Then, by fixing with the set screw 94, the position after the focus adjustment can be held. The lens tilt hole 95 is for adjusting the position of the condensing lens 69 with respect to the housing 59, and can finely adjust the focal point of the light focused on the line sensor 62. An adjustment pin (not shown) that matches the diameter of the lens tilt hole 95 is inserted into the lens tilt hole 95, and the condensing lens 69 is slightly rotated about the fulcrum 96, so that the light focused by the condensing lens 69 is reflected. The imaging position can be maintained on the sensor surface of the line sensor 62 with high accuracy. And the position after fine adjustment can be hold | maintained by fixing with the screw 97. FIG.
[0028]
The line sensor 62 has a CCD substrate 62a, and the angle of the CCD substrate 62a with respect to the housing 59 can be adjusted by a sensor tilt adjusting block 80 as an optical sensor adjusting means. The sensor tilt adjustment block 80 is for adjusting the position of the line sensor 62 with respect to the housing 59. The adjustment screw 81 moves one side of the CCD substrate 62a in a direction parallel to the optical axis, and is fixed by a set screw 82. Thus, the position after the angle adjustment can be held.
[0029]
The movable mirror 63 is supported by a mirror fulcrum 60, and a gear 75 attached to the mirror fulcrum 60 meshes with a gear 74. The gear 74 meshes with the gear 73, and the gear 73 meshes with the worm wheel 72. The worm wheel 72 meshes with the worm 71 of the motor 70 attached to the housing 59. The motor 70 is, for example, a stepping motor. When the motor 70 is energized, the movable mirror 63 can be rotated around the mirror fulcrum 60 via the worm 71, the worm wheel 72, the gear 73, the gear 74, and the gear 75. it can.
[0030]
When instructing the image reading apparatus 1 using a personal computer, the image reading apparatus 1 is controlled by software such as a scanner driver such as TWAIN installed in the personal computer. When the user selects reading of the transparent original on the TWAIN activated on the personal computer, the motors 50 and 70 are energized in response to the transparent original selection command, and the worm 51, the worm wheel 52, the gear 53, and the helical spline 20a. Then, the main lens holder 20 is driven, and the condenser lens 67 and the condenser lens 69 are switched to change from the state shown in FIG. 1 to the state shown in FIG. Further, the movable mirror 63 is rotated about the mirror fulcrum 60 via the worm 71, the worm wheel 72, the gear 73, the gear 74, and the gear 75, and the optical path is switched to change from the state shown in FIG. 2 to the state shown in FIG. Become.
[0031]
Next, a method for adjusting the carriage 6 configured as described above will be described.
1. The motor 50 is energized, and as shown in FIGS. 1 and 2, the condenser lens 67 is moved to the approximate center of the carriage 6, that is, on the optical path. An adjustment pin is inserted into the focus adjustment groove 91 of the main lens holder 20, the focusing lens 67 is moved in a direction parallel to the optical axis, and the imaging position of the light collected by the focusing lens 67 is adjusted by the line sensor 62. The focus adjustment position is held by fixing with a set screw 92 in accordance with the sensor surface.
[0032]
2. In order to obtain the perpendicularity between the optical axis of the condensing lens 67 and the sensor surface of the line sensor 62, the angle of the CCD substrate 62a is adjusted by the adjustment screw 81 of the sensor tilt adjustment block 80, and is fixed by the set screw 82 to obtain the perpendicularity. Hold.
[0033]
3. The motors 50 and 70 are energized, and as shown in FIG. 3, the condenser lens 69 is moved to the approximate center of the carriage 6, that is, on the optical path, and the movable mirror 63 is moved around the mirror fulcrum as shown in FIG. Turn to switch the optical path length. An adjustment pin is inserted into the focus adjustment groove 93 of the sub lens holder 21, the focusing lens 69 is moved in a direction parallel to the optical axis, and the imaging position of the light collected by the focusing lens 69 is adjusted by the line sensor 62. The focus adjustment position is held by fixing with a set screw 94 in accordance with the sensor surface.
[0034]
4). At this time, when the angle of the CCD substrate 62a is adjusted by the sensor tilt adjustment block 80 in order to obtain a perpendicular angle between the optical axis of the condenser lens 69 and the sensor surface of the line sensor 62, the optical axis and line of the condenser lens 67 are adjusted. The perpendicularity between the sensor 62 and the sensor surface is incorrect. Accordingly, an adjustment pin is inserted into the lens tilt hole 95 of the sub lens holder 21, the focusing lens 69 is slightly rotated about the fulcrum 96, and the imaging position of the light focused by the focusing lens 69 is detected by the line sensor 62. The sensor surface is maintained with high accuracy and fixed with a screw 97 to hold the position after fine adjustment.
[0035]
Next, the above 1. ~ 4. The operation of the image reading apparatus 1 adjusted by the adjustment method will be described.
(1) The user connects a personal computer (not shown) to the interface 8 of the image reading apparatus 1, places the document 5 on the document table 3, and designates the reading range and the reading resolution of the document 5 from the personal computer. Instruct execution. At this time, the user also instructs whether the original to be read is a reflective original or a transparent original.
[0036]
(2) When execution of reading is instructed, the control unit 15 turns on the light source 61 or the surface light source 68 and sequentially moves the carriage 6 to each reading line position at a constant speed. As a result, the charge (signal charge) in an amount proportional to the reflectance (darkness) or transmittance of the document 5 is accumulated in the line sensor 62 at each reading line position.
[0037]
(3) The charge accumulated in the line sensor 62 is output to the amplifier 10 after a predetermined time has elapsed, and the line sensor 62 moves to the next reading line position.
(4) The output signal from the amplifier 10 is converted into digital light amount signal data by the A / D conversion unit 11, and various corrections are performed by the shading correction unit 12, the gamma correction unit 13, and the other correction units 14. The data is output to a personal computer or the like via the interface 8.
[0038]
(5) By repeating the processes (2) to (4) for each reading line while the carriage 6 moves at a constant speed, an image in the designated range is output to a personal computer or the like.
[0039]
In the embodiment of the present invention described above, the imaging position of the light condensed by the condenser lens 67 by the focus adjustment groove 91 of the main lens holder 20 is matched with the sensor surface of the line sensor 62, and the sensor tilt adjustment block 80. The right angle between the optical axis of the condensing lens 67 and the sensor surface of the line sensor 62 is obtained by switching between the condensing lens 67 and the condensing lens 69, and then the condensing lens is formed by the focus adjustment groove 93 of the sub lens holder 21. The imaging position of the light condensed at 69 is matched with the sensor surface of the line sensor 62 and fine adjustment is performed by the lens tilt hole 95. For this reason, the imaging positions of both the light focused by the condensing lens 67 and the light focused by the condensing lens 69 can be maintained on the sensor surface of the line sensor 62 with high accuracy. Therefore, by switching between the condensing lens 67 and the condensing lens 69 by energizing the motor 50, the transparent original can be read with higher resolution than the reflective original.
[0040]
Further, in the present embodiment, the movable mirror 63 can be rotated about the mirror fulcrum 60, so that the optical path length can be easily increased when the reflected original is read and the transparent original is read by energizing the motor 70. Can be switched. Therefore, when the condenser lens 67 and the condenser lens 69 are switched, the optical path length can be easily switched with a simple structure by rotating the movable mirror 63. Therefore, the physique of the carriage 6 can be reduced in size, and a mounting space can be easily secured.
[0041]
In the embodiment of the present invention described above, the lens tilt hole 95 is formed in the sub-lens holder 21, and the focusing position of the light focused by the condenser lens 67 is maintained on the sensor surface of the line sensor 62. Although the present invention is applied to the image reading apparatus 1 configured to maintain the imaging position of the light focused by the lens 69 on the sensor surface of the line sensor 62, a lens tilt hole is formed in the main lens holder 20, and the condenser lens 69. The image reading apparatus is configured to maintain the imaging position of the light focused by the condensing lens 67 on the sensor surface of the line sensor 62 after maintaining the imaging position of the light focused by the focusing sensor 67 on the sensor surface. It goes without saying that can be applied.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a carriage when reading a reflection original of an image reading apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic view showing a carriage when reading a reflection original of an image reading apparatus according to an embodiment of the present invention.
FIG. 3 is a schematic view showing a carriage when a transparent original is read by the image reading apparatus according to the embodiment of the present invention.
FIG. 4 is a schematic diagram illustrating a carriage when a transparent original is read by the image reading apparatus according to the embodiment of the present invention.
FIG. 5 is a schematic diagram illustrating a case where a reflection original is read by the image reading apparatus according to the embodiment of the present invention.
FIG. 6 is a block diagram illustrating an image reading apparatus according to an embodiment of the present invention.
FIG. 7 is a schematic diagram illustrating a case where a transparent original is read by the image reading apparatus according to the embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Image reader 3 Document stand 6 Carriage 20 Main lens holder 20a Helical spline (switching means)
21 Sub lens holder 50 Motor (switching means)
51 Worm (switching means)
52 Worm wheel (switching means)
53 Gear (switching means)
59 Housing 61 Light source 62 Line sensor (light sensor)
63 Movable mirrors 64, 65, 66 Mirror 67 Condensing lens (first lens)
68 Surface light source 69 Condensing lens (second lens)
80 Sensor tilt adjustment block (Optical sensor adjustment means)
91, 93 Focus adjustment groove (Focus adjustment means)
95 Lens tilt hole (Lens adjustment means)

Claims (7)

A carriage capable of reciprocating in parallel with an original table on which an original is placed;
A light source for illuminating the document;
A first mirror that reflects light reflected from or transmitted through the document surface;
A first lens for condensing the reflected light of the first mirror;
A second mirror that reflects light reflected or transmitted through the original surface by an optical path different from that of the first mirror;
A second lens having a magnification different from that of the first lens and collecting the reflected light of the second mirror;
An optical sensor that converts light collected on the first lens or the second lens into an electrical signal;
A housing that houses the light source, the mirror, the first lens, the second lens, and the photosensor;
Switching means for switching the lens that focuses the light sensor to the first lens or the second lens;
An optical sensor adjusting means for adjusting a position of the optical sensor with respect to the housing;
Lens adjusting means for adjusting the position of the first lens or the second lens with respect to the housing;
A carriage comprising: The carriage according to claim 1, wherein the first mirror or the second mirror includes a movable mirror that is movable by the housing. 3. The carriage according to claim 1, wherein one or both of the first lens and the second lens includes a focus adjusting unit that adjusts a focus of light focused on the optical sensor. An image reading apparatus comprising the carriage according to claim 1. A light source for irradiating a document, a first mirror for reflecting light reflected on or transmitted through the document surface, a first lens for collecting the reflected light of the first mirror, and a document reflected on the document surface or the document A second mirror that reflects the light transmitted through the first mirror by an optical path different from that of the first mirror, and a second mirror that condenses the reflected light of the second mirror having a magnification different from that of the first lens. A lens, an optical sensor that converts light condensed on the first lens or the second lens into an electrical signal, the light source, the mirror, the first lens, the second lens, and the light A method of adjusting a carriage that is reciprocally movable in parallel with a document table on which the document is placed.
Adjusting the position of the photosensor relative to the housing;
Switching the lens condensing on the photosensor to the first lens or the second lens;
Adjusting the position of the first lens or the second lens relative to the housing;
A method for adjusting a carriage, comprising: Adjusting the focus of the light focused on the photosensor of either the first lens or the second lens before the step of adjusting the position of the photosensor relative to the housing. 6. The carriage adjusting method according to claim 5, wherein the carriage is adjusted. Prior to the step of adjusting the position of the first lens or the second lens with respect to the housing, the focal point of the light focused on the other optical sensor of the first lens or the second lens. The method of adjusting a carriage according to claim 6, further comprising a step of adjusting

Images