JP2020053773A - Irradiation device and reader - Google Patents

Abstract

To make it possible to reduce a configuration as compared with a case where physically providing two sets of light sources and light guide members for irradiating an object with light in two different irradiation directions.SOLUTION: The irradiation device includes: a light source for outputting illumination light; and emitting means for emitting as first illumination light, which is the illumination light propagating in an axial direction of a rod-shaped light guide member, entering a reading position of an object at a first angle from a side face of the light guide member and second illumination light, entering at an angle different from the first angle; and reflecting means for reflecting the second illumination light so as to be incident on the reading position at an incident angle smaller than the first illumination light with respect to the normal direction of the reading position of the object.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an irradiation device and a reading device.

  Patent Document 1 discloses an image reading apparatus including: a photoelectric conversion unit configured to irradiate a document with light, input reflected light reflected from the document in a predetermined reflection direction, and perform photoelectric conversion to generate image data. A first irradiation direction in which the document is illuminated from each of a first irradiation direction in which the reflected light is mainly diffuse reflection light and a second irradiation direction in which the reflected light is mainly specular reflection light And a second light source, a reflection-side light guide unit that guides the reflected light to the photoelectric conversion unit, and the reflection light corresponding to the light of the first and second light sources is input to the photoelectric conversion unit and generated. Image data synthesizing means for synthesizing the image data of the original by selecting one of the data for each of the corresponding positions based on the comparison of the data at the mutually corresponding positions in the two image data. Prepare Image reading apparatus according to claim Rukoto "is described.

Patent No. 4083042

  When physically providing a light source and a light guide member for irradiating light at two different angles with respect to the reading position of the object, a plurality of configurations are required.

  An object of the present invention is to reduce the configuration as compared with a case where two light sources and two light guide members that irradiate light in two different irradiation directions to an object are physically provided.

According to the first aspect of the present invention, a light source that outputs illumination light, and the illumination light that is propagated in the axial direction of the rod-shaped light guide member is moved from a side surface of the light guide member to a reading position of an object to be imaged. Emitting means for emitting first illumination light incident at a first angle and second illumination light incident at an angle different from the first angle with respect to the normal direction of the reading position of the object to be imaged; On the other hand, a reflection unit that reflects the second illumination light so that the light enters the reading position at an incident angle smaller than that of the first illumination light.
The invention according to claim 2 controls optical switching of the relationship between the amount of light that the first illumination light is incident on the object and the amount of light that the second illumination light is incident on the object. The irradiation device according to claim 1, further comprising a control unit.
The invention according to claim 3 is the irradiation device according to claim 2, wherein the control unit changes a position of the light blocking unit.
The invention according to claim 4 is the irradiation device according to claim 3, wherein the light shielding unit moves around the emitting unit.
The invention according to claim 5 is the irradiation apparatus according to claim 2, wherein the control means controls an optical element capable of electrically adjusting the amount of transmitted light.
The invention according to claim 6, wherein the optical element is a liquid crystal shutter, and the first illumination light and the second illumination light are respectively arranged on an optical path leading to an object to be imaged. 5. The irradiation device according to 5.
The invention according to claim 7 is the irradiation apparatus according to claim 2, wherein the control unit does not block the first illumination light and blocks only a part of the second illumination light. is there.
The invention according to claim 8 is the irradiation device according to claim 1, wherein the emission unit switches between emission of the first illumination light and emission of the second illumination light by rotational movement.
The invention according to claim 9 is the illumination device according to claim 1, wherein the reflection unit is arranged at a position that is not on a normal line of a position where the second illumination light is incident on the object. is there.
According to a tenth aspect of the present invention, the reflecting means is arranged at a position where the object does not obstruct the optical path of the reflected light reflecting the first illumination light or the second illumination light. An irradiation device according to item 1.
According to an eleventh aspect of the present invention, the reflection unit has a first reflection member and a second reflection member, and the first reflection member is located at a position where the second illumination light is incident on the object. 2. The irradiation device according to claim 1, wherein the irradiation unit is arranged in a space closer to the emission unit than the normal line, and the second reflection member is arranged in a space deeper than the normal line when viewed from the emission unit. Device.
According to a twelfth aspect of the present invention, a light source that outputs illumination light, and the illumination light that is propagated in the axial direction of the rod-shaped light guide member is moved from a side surface of the light guide member to a reading position of an object to be imaged. Emitting means for emitting first illumination light incident at a first angle and second illumination light incident at an angle different from the first angle with respect to the normal direction of the reading position of the object to be imaged; Reflecting means for reflecting the second illumination light so as to enter the reading position at an incident angle smaller than that of the first illumination light, and a light amount with which the first illumination light is incident on the object. Control means for controlling the optical switching of the relationship between the second illumination light and the amount of light incident on the object, receiving the reflected light from the object, converting the light into image data, and reading the image A reading device having a reading unit.
According to a thirteenth aspect of the present invention, the control unit is configured to read an image in a state in which only the first illumination light is incident on the object, and to cause only the second illumination light to enter the object. 13. The reading apparatus according to claim 12, wherein the reading apparatus switches a mode for reading an image in a state.
According to a fourteenth aspect of the present invention, the control unit causes the mode in which an image is read in a state where only the first illumination light is incident on the object, and the control unit causes only the second illumination light to be incident on the object. 13. The reading apparatus according to claim 12, wherein the reading apparatus switches between a mode for reading an image in a state and a mode for reading an image in a state in which both the first illumination light and the second illumination light are incident on an object. .
In the invention according to claim 15, the control means performs control so that the entirety of the first illumination light and a part of the second illumination light are mixed and incident on the object. 2. The reading device according to item 1.
According to a sixteenth aspect of the present invention, in the mode in which only the first illumination light is made incident on the object and the reflected light of the object is read and the image is read, the control unit controls the light shielding unit. In a mode in which the second illumination light is moved to a position where the second illumination light is shielded, and only the second illumination light is incident on the object, the reflected light of the object is received, and an image is read, the light-shielding means is used. 13. The reading device according to claim 12, wherein the reading device is moved to a position where the first illumination light is blocked.
The invention according to claim 17 is characterized in that, in a mode in which both the first illuminating light and the second illuminating light are made incident on the object and the image of the object is read, the control unit controls the light shielding. 17. The reading apparatus according to claim 16, wherein the means is moved to a position at which both the first illumination light and the second illumination light are not blocked.
According to an eighteenth aspect of the present invention, the control unit reads an image of the object by mixing all of the first illumination light and a part of the second illumination light so as to be incident on the object. 18. The reading device according to claim 16, wherein in the case of the mode, the light shielding unit is moved to a position where only a part of the second illumination light is shielded.
The invention according to claim 19 is the reading apparatus according to claim 12, wherein the reflected light of the object to be picked up with respect to the second illumination light includes a component related to the texture of the object to be picked up.
The invention according to claim 20 is the reading apparatus according to claim 16, further comprising a variable mechanism that changes a position of the light shielding unit.
The invention according to claim 21 is the reading device according to claim 12, further comprising an optical element capable of electrically adjusting the amount of transmitted light.
22. The invention according to claim 22, wherein the optical element is a liquid crystal shutter, and the first illumination light and the second illumination light are respectively arranged on an optical path leading to an object to be imaged. 22. The reading device according to 21.
The invention according to claim 23 is the reading device according to claim 22, wherein the liquid crystal shutter does not block the first illumination light and blocks only a part of the second illumination light. is there.
The invention according to claim 24 is the reading device according to claim 12, wherein the emission unit switches between emission of the first illumination light and emission of the second illumination light by rotational movement.
The invention according to claim 25 is the reading device according to claim 12, wherein the reflection unit is arranged at a position that is not on a normal line of a position where the second illumination light is incident on the object. is there.
The invention according to claim 26, wherein the reflection means is arranged at a position where the object does not obstruct the optical path of the reflected light reflecting the first illumination light or the second illumination light. 2. The reading device according to item 1.
The invention according to claim 27, wherein the reflecting means has a first reflecting member and a second reflecting member, and the first reflecting member is located at a position where the second illumination light is incident on the object. 13. The reading device according to claim 12, wherein the second reflection member is disposed in a space farther than the normal when viewed from the emission unit, and is disposed in a space closer to the emission unit than a normal line. Device.

According to the first aspect of the present invention, the configuration can be reduced as compared with a case where two light sources and two light guide members are provided to irradiate the object with light in two different irradiation directions.
According to the second aspect of the present invention, it is possible to switch the amount of two different lights incident on the object even with one light source.
According to the third aspect of the present invention, switching of the amount of light can be realized at low cost.
According to the fourth aspect of the present invention, switching of the amount of light can be realized at low cost.
According to the fifth aspect of the present invention, it is possible to improve the reliability of switching the light amount.
According to the invention described in claim 6, the reliability of switching the light amount can be improved.
According to the seventh aspect of the present invention, it is possible to switch the amount of two different lights incident on the object even with one light source.
According to the eighth aspect of the present invention, it is possible to eliminate the need for the light shielding member.
According to the ninth aspect, there is no need to impede reading of reflected light.
According to the tenth aspect, there is no need to impede reading of reflected light.
According to the eleventh aspect, an image with few shadows can be obtained.
According to the twelfth aspect, the configuration of the reading device can be reduced as compared with a case where two light sources and two light guide members are provided to irradiate the object with light in two different irradiation directions.
According to the thirteenth aspect, color information and texture information can be read separately.
According to the fourteenth aspect, it is possible to accurately read the color information and the texture information.
According to the fifteenth aspect, the color information and the texture information can be read at a time.
According to the sixteenth aspect, color information and texture information can be read separately.
According to the seventeenth aspect, the reading time of the color information can be reduced.
According to the eighteenth aspect, color information and texture information can be read at once.
According to the nineteenth aspect, it is possible to read the texture of the object.
According to the twentieth aspect, switching of the light amount can be realized at low cost.
According to the twenty-first aspect, the reliability of switching the light amount can be improved.
According to the invention described in claim 22, the reliability of switching the light amount can be improved.
According to the twenty-third aspect, color information and texture information can be read at once.
According to the invention of claim 24, one illumination light can be used for reading color information and for reading texture information.
According to the twenty-fifth aspect, there is no need to impede reading of reflected light.
According to the twenty-sixth aspect, there is no need to impede reading of reflected light.
According to the twenty-seventh aspect, an image with few shadows can be obtained.

FIG. 2 is a diagram illustrating an example of an external appearance of an image forming apparatus having a texture reading function. FIG. 2 is a diagram illustrating a connection relationship between modules constituting the image forming apparatus. FIG. 2 is a diagram illustrating a configuration example of an image reading device used in the first embodiment. FIG. 2 is a diagram illustrating an example of an appearance of a light source module used in the image reading device. FIG. 4 is a diagram illustrating an example of a reflection image acquired by the image reading device. (A) is an example of a diffuse reflection image, (b) is an example of a regular reflection image, and (c) is an example of a difference image between the diffuse reflection image and the regular reflection image. FIG. 3 is a diagram illustrating an example of a function of an image processing unit. 5 is a flowchart illustrating an example of a control operation performed by a control board. FIG. 4 is a diagram illustrating the position of a movable shutter during a diffuse reflection image reading mode. FIG. 4 is a diagram illustrating the position of a movable shutter during a regular reflection image reading mode. 9 is a flowchart illustrating another example of the control operation by the control board. FIG. 7 is a diagram illustrating the position of a movable shutter during a mode of reading a diffuse reflection image with a high light amount. 9 is a flowchart illustrating another example of the control operation by the control board. FIG. 5 is a diagram illustrating the position of a movable shutter during a mixed reading mode. FIG. 9 is a diagram illustrating a configuration example of an image reading device used in a second embodiment. FIG. 14 is a diagram illustrating an example of an appearance of a light source module used in the image reading device according to the second embodiment. FIG. 3 is a diagram illustrating an example of controlling a liquid crystal shutter by a control board. FIG. 13 is a diagram illustrating a configuration example of an image reading device used in a third embodiment. FIG. 14 is a diagram illustrating an example of an appearance of a light source module used in an image reading device according to a third embodiment. FIG. 4 is a diagram illustrating a positional relationship of a light guide member when used in a diffuse reflection image reading mode. FIG. 4 is a diagram illustrating a positional relationship of a light guide member when used in a regular reflection image reading mode. FIG. 7 is a diagram illustrating an example in which a reflection mirror is arranged on the rear side with respect to a normal axis of a reading position. It is a figure explaining the example of arrangement at the time of using two reflection mirrors.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
<Overall Configuration of Image Forming Apparatus>
FIG. 1 is a diagram illustrating an example of an appearance of an image forming apparatus 1 having a texture reading function.
The image forming apparatus 1 includes an image reading device 10 that reads an image of a document, and an image recording device 20 that records an image on a sheet, which is an example of a recording medium.
The document here is an example of the object to be imaged.

The image reading device 10 is mounted on an upper surface of an image recording device 20 that forms a main body of the device. The image reading apparatus 10 includes an image reading unit that optically reads an image formed on a document, and a document transport unit that transports the document to the image reading unit.
The image recording device 20 includes a mechanism for forming an image on the surface of a sheet and a mechanism for conveying the sheet. The image recording device 20 forms an image on a sheet pulled out from the sheet tray 30. The image recording device 20 is mounted on the upper surface of the paper tray 30.

FIG. 2 is a diagram illustrating a connection relationship between modules constituting the image forming apparatus 1.
The image recording device 20 is provided with a control device 21 for controlling the operation of the entire device.
The control device 21 includes a CPU (Central Processing Unit) 21A, a ROM (Read Only Memory) 21B in which firmware and a BIOS (Basic Input Output System) are stored, and a RAM (Random Access Unit) used as a work area of the control device 21A. Memory) 21C. The control device 21 forms a so-called computer.

The image recording device 20 has a hard disk device (HDD) 22 which is an example of a nonvolatile storage device. The hard disk device 22 stores image data read by the image reading device 10, print data supplied from the outside, image data transmitted and received through FAX communication, and the like.
Further, the image recording device 20 is provided with a display unit 23 and an operation receiving unit 24 as a user interface. As the display unit 23, for example, a liquid crystal display or an organic EL (Electro Luminescence) display is used. For example, a touch sensor is used for the operation receiving unit 24.

Further, the image recording device 20 is provided with an image processing unit 25 that executes various processes (for example, color correction and gradation correction) required for forming an image. Further, the image recording device 20 is provided with an image forming unit 26 that records an image on a sheet. The image forming unit 26 records an image by, for example, an electrophotographic method or an inkjet method. The image recording device 20 is provided with a communication unit 27 that communicates with an external device via a network.
Incidentally, the control device 21 and each part are connected via a bus 28 or a signal line (not shown).

<Configuration of image reading device>
FIG. 3 is a diagram illustrating a configuration example of the image reading device 10 used in the first embodiment. FIG. 4 is a diagram illustrating an example of the appearance of the light source module 40 used in the image reading device 10. The image reading device 10 is an example of a reading device, and the light source module 40 is an example of an irradiation device.
The image reading apparatus 10 shown in FIG. 3 optically reads the surface of a document and outputs two types of image data as a reading result.
One of the image data is an image of a light component diffusely reflected on the surface of the document (hereinafter, referred to as a “diffuse reflection image”), and the other includes a large amount of light component regularly reflected on the surface of the document. An image (hereinafter, referred to as a “specular reflection image”). Specular reflection is reflection in which the incident angle and the reflection angle of light are the same angle with respect to the reflection surface, and is also called specular reflection. In the present embodiment, the specular reflection image includes a small amount of light components diffusely reflected on the surface of the document in addition to light components regularly reflected on the surface of the document.

FIG. 3 shows a platen glass 11 on which an original is arranged and a carriage 12 having a built-in optical system for reading, of the image reading apparatus 10. The platen glass 11 is attached to a casing (not shown), and the carriage 12 is built in the casing (not shown).
The platen glass 11 is a glass plate that supports a document, and has a flat plate shape. The surface of the document supported by the platen glass 11 is the reading surface. The platen glass 11 may be a transparent member, and the material is not limited to glass. For example, an acrylic plate may be used.
When the surface of the document is optically read, the periphery of the document may be covered by a light-shielding cover member so that external light does not enter the carriage 12.

The carriage 12 is provided with a light source module 40 that emits two types of light beams L1 and L2 used for reading a document, and a light receiving unit 50 that receives light reflected from the document.
The light source module 40 includes a light source 41 that outputs illumination light, a light guide member 42 that propagates the illumination light emitted from the light source 41, and linear light beams L1 and L2 that are emitted from side surfaces of the light guide member 42. Among them, a reflection mirror 43 that reflects the light beam L2 in the direction of the original, a movable shutter 44 that is rotated around the light guide member 42 as an axis, and a control board 45 are provided.
These members are all attached to the housing 40A. Here, the movable shutter 44 is an example of a light shielding unit, and the control board 45 is an example of a control unit.

In the case of the present embodiment, there is one light source 41, and the light source 41 is arranged at one end of the light guide member 42. As the light source 41, for example, a white LED (Light Emitting Diode) is used. Illumination light emitted from the light source 41 is propagated in the axial direction (X-axis direction) inside the light guide member 42 having a substantially cylindrical shape or a rod shape.
The illumination light propagating inside the light guide member 42 is converted into light components in two directions orthogonal to the propagation direction by the prism structures 42A and 42B formed along the axial direction of the light guide member 42. The converted illumination light is emitted from the side surface of the light guide member 42 to the outside as light rays L1 and L2.
The prism structures 42A and 42B are designed so that the distribution of illuminance at the reading position of the document irradiated by the light beams L1 and L2 becomes uniform.
Here, the light ray L1 is an example of the first illumination light, and the light ray L2 is an example of the second illumination light. The light guide member 42 that emits the light beams L1 and L2 is an example of an emission unit.

In the case of FIG. 3, the light beam L1 is emitted in a direction for directly irradiating the reading position of the document. In the case of the present embodiment, the light beam L1 is emitted at the reading position so as to be incident at an angle of approximately 45 ° with respect to the normal direction (vertical direction) to the surface of the document. This incident angle is an example of a first angle.
The light beam L2 is emitted in the direction of the reflection mirror 43. In the case of the present embodiment, after being reflected by the reflection mirror 43, the light beam L2 is emitted at the reading position so as to be incident at an angle of approximately 5 ° with respect to the normal direction (vertical direction) to the surface of the document. . This incident angle is an example of the second angle. The incident angle of the light beam L2 is preferably approximately 5 ° to approximately 10 °. The incident angle of the light beam L2 may be adjusted by the mounting angle of the reflection mirror 43.
The reflection mirror 43 is an example of a reflection unit that reflects the light beam L2 such that the incident angle of the light beam L2 with respect to the reading position is smaller than the incident angle of the light beam L1. The reflecting mirror 43 in the present embodiment has a reflecting surface longer than the width of the light beam L2 output linearly. In other words, the reflection mirror 43 has the same length as the light guide member 42. The positions of the reflection mirror 43 and the light guide member 42 are parallel.

The movable shutter 44 in the present embodiment is made of an impermeable material. For example, it is made of metal or plastic. The movable shutter 44 is a band-shaped member extending in the axial direction of the light guide member 42, and has a length sufficient to shield light beams L <b> 1 and L <b> 2 emitted from the light guide member 42. However, the movable shutter 44 may be a cylindrical member in which an opaque portion and a permeable portion are arranged in a circumferential direction, or a member having an equivalent structure and an arc-shaped cross section.
The movable shutter 44 in the present embodiment is guided by a guide mechanism (not shown) provided in the housing 40A, and is moved so as to cross the optical path of the light beam L1 or L2. In the case of the present embodiment, the movement of the movable shutter 44 is executed by a drive mechanism (not shown). The guide mechanism and the drive mechanism here are examples of a variable mechanism that changes the position of the light blocking unit. In the case of the present embodiment, the movable shutter 44 is rotatably moved along the outer periphery of the light guide member 42 having a substantially cylindrical or rod shape.
In the case of the present embodiment, the movable shutter 44 is moved to any one of a position where the light beam L1 is blocked, a position where the light beam L2 is blocked, and a position where neither the light beam L1 nor the light beam L2 is blocked.

The control board 45 performs control of turning on or off the light source 41, control of movement of the movable shutter 44, and the like. The position where the movable shutter 44 is stopped is predetermined in accordance with the reading mode. The reading mode is notified from the control device 21 (see FIG. 2) to the control board 45.
In the present embodiment, the axial direction (X direction in the drawing) of the light guide member 42 is referred to as a main scanning direction, and the direction indicated by an arrow in FIG. 3 (Y direction in the drawing) is referred to as a sub-scanning direction.
Therefore, when reading the information of the document, the carriage 12 is driven to move in the sub-scanning direction. The moving speed is predetermined according to the reading mode.
Hereinafter, the direction in which the carriage 12 moves is referred to as the front (front) side, and the opposite side is referred to as the rear (rear) side. The light source module 40 in FIG. 3 is disposed on the front side with respect to the reading position where the light beams L1 and L2 irradiate the document. In FIG. 3, the position where the light beam L1 and the light beam L2 intersect is the reading position. Of course, the light source module 40 may be configured to be disposed on the rear side.

The light receiving unit 50 is provided with an imaging optical system 51 that forms an image of light reflected at the reading position by the light beams L1 and L2, and an image sensor 52 that receives the formed light. Here, the light receiving unit 50 is an example of a reading unit.
The imaging optical system 51 includes, for example, a reflection mirror and an imaging lens, and forms an image of a component of diffuse reflection light and a component of regular reflection light reflected at the reading position on a light receiving surface of the image sensor 52. In the case of FIG. 3, the imaging optical system 51 is arranged on the normal line of the platen glass 11, but the mounting position of the imaging optical system 51 is not limited. A reflection mirror may be provided on the normal line of the platen glass 11 to refract light reflected from the document, and the mounting position of the imaging optical system 51 may be provided on the side surface of the carriage 12 or outside the housing of the carriage 12. Then, it may be provided on the optical axis of the light reflected by the reflection mirror.
In the present embodiment, the light component reflected in the normal direction of the platen glass 11 among the light rays L1 incident on the reading position at an incident angle of approximately 45 ° is called diffuse reflection light. A light component of the light beam L2 incident on the reading position with an incident angle of approximately 5 ° to approximately 10 ° and largely reflected in the normal direction of the platen glass 11 is referred to as regular reflection light.

The image sensor 52 reads the original as image data by outputting the intensity of the diffuse reflection light and the regular reflection light formed on the light receiving surface as an image signal. An image formed by an image signal corresponding to diffuse reflection light is called a diffuse reflection image, and an image formed by an image signal corresponding to specular reflection light is called a regular reflection image.
As the image sensor 52, for example, a light receiving element such as a CCD (Charge Coupled Device) linear image sensor or a CMOS (Complementary MOS) image sensor is used. A color filter (not shown) is arranged on the surface of the image sensor 52. Therefore, the diffuse reflection image and the specular reflection image are given by a color image signal. In the case of the present embodiment, it is given by three color component values of red (R), green (G), and blue (B).

FIG. 5 is a diagram illustrating an example of a reflection image acquired by the image reading device 10 (see FIG. 3). (A) is an example of a diffuse reflection image, (b) is an example of a regular reflection image, and (c) is an example of a difference image between the diffuse reflection image and the regular reflection image.
The reflection image shown in FIG. 5 is obtained when a color chart in which 16 color patches (hereinafter, also referred to as “patches”) having different combinations of colors and densities are arranged in a matrix on the surface of the document is printed. You. Each patch constituting the color chart is an example of a sample pattern.
The horizontal axis of the color chart corresponds to four colors having different combinations of the hue and the gloss component, and the vertical axis corresponds to the coverage indicating the amount of the color material used when printing the document. The lower the coverage, the smaller the amount of color material per unit area and the lower the color density. On the other hand, the higher the coverage, the greater the amount of color material per unit area, and the higher the color density.

In the case of FIG. 5, the four colors constituting the color chart include a mixed color of cyan and silver (hereinafter also referred to as “cyan + silver color”), a mixed color of magenta and silver (hereinafter also referred to as “magenta + silver color”), magenta, It is cyan.
The color chart shown in FIG. 5 includes color patches in which the coverage is changed in four stages for each color. The color patches shown in FIG. 5 have the same shape. Specifically, the color patches are square.

As described above, the specular reflection image shown in (b) is an image mainly obtained from the metallic gloss component on the surface of the document, but also includes a diffuse component. Here, the metallic luster corresponds to the metallic color expressed by the silver toner.
(C) is a difference image expressing the metallic luster included in the regular reflection image. The difference image is generated by calculating a difference between the diffuse reflection image and the regular reflection image.
Since the metallic luster is basically generated by the silver toner, in the difference image, a gloss component appears in two rows of a color patch corresponding to the cyan + silver color and a color patch corresponding to the magenta + silver color including the silver toner. I have. Further, the difference in the coverage also appears in the difference in the reflectance of the metallic luster. That is, the higher the coverage, the brighter the color patch looks.

Returning to the description of FIG. 3 and FIG.
In the case of the carriage 12 used in the present embodiment, the relationship between the incident angles of the light beams L1 and L2 with respect to the document and the light receiving angles received by the image sensor 52 is kept constant over the entire surface of the document. This relationship cannot be realized by imaging with an imaging camera or the like.
For this reason, the difference between the diffuse reflection image acquired under the diffuse reflection condition (the incident angle is approximately 45 °) and the regular reflection image acquired under the regular reflection condition (the incident angle is approximately 10 °) is calculated. This makes it possible to accurately extract information on metallic luster. This means that the metallic luster area and the reflectance (specular reflectance on a two-dimensional plane) can be acquired at once by a simple difference calculation.
Note that the condition of diffuse reflection (the incident angle is approximately 45 °) and the condition of specular reflection (the incident angle is approximately 5 °) are calibrated by the same white calibration plate.

FIG. 6 is a diagram illustrating an example of a function of the image processing unit 25 (see FIG. 2).
The image processing unit 25 illustrated in FIG. 6 includes a difference image acquisition unit 25A and average value calculation units 25B and 25C as processing functions of a reflection image.
The difference image obtaining unit 25A calculates a difference between the diffuse reflection image and the regular reflection image for each pixel to obtain a difference image. There are two methods for obtaining the difference image, a method for obtaining the difference image by subtracting the diffuse reflection image from the regular reflection image, and a method for obtaining the difference image by subtracting the regular reflection image from the diffuse reflection image. The difference image acquisition unit 25A calculates the difference image by one or both methods.

The average value calculation unit 25B calculates an average RGB value of the diffuse reflection image. When a color chart is printed on a document, the average value calculation unit 25B calculates an average RGB value for each color patch. In the case of FIG. 6, the average RGB value is (R, G, B) = (185, 151, 95).
The average value calculation unit 25C calculates an average RGB value of the difference image corresponding to the color patch. Of course, when the color chart is printed on the document, the average value calculation unit 25C calculates the average RGB value for each color patch. In the present embodiment, the average RGB value of the difference image is represented by an average ΔRΔGΔB value for distinction. Δ represents a difference. The average ΔRΔGΔB value is an example of an average pixel value.
In the case of FIG. 6, the average ΔRΔGΔB value is (ΔR, ΔG, ΔB) = (69, 88, 88). The average ΔRΔGΔB value here corresponds to the gloss component value.

The image reading apparatus 10 according to the present embodiment can acquire texture information of a document by basically performing two scans. The two scans are a scan for irradiating the original with the light beam L1 to obtain a diffuse reflection image and a scan for irradiating the original with the light beam L2 to obtain a regular reflection image.
The method according to the present embodiment can reduce the time required for acquiring texture information as compared with a method of measuring a BRDF (Bidirectional Reflectance Distribution Function). Further, the method according to the present embodiment can calculate texture information by a difference operation, so that the load on calculation resources can be reduced.

<Read operation>
Hereinafter, an operation of reading a document by image reading apparatus 10 (see FIG. 3) according to the present embodiment will be described.

<Operation example 1>
FIG. 7 is a flowchart illustrating an example of a control operation performed by the control board 45 (see FIG. 4). The symbol S in the figure means a step.
In the case of the present embodiment, an instruction to start reading is given to the control board 45 from the control device 21 (see FIG. 2).
First, the control board 45 determines whether or not to start reading (step 1).
While the negative result is obtained in step 1, the control board 45 waits for reception of the reading start instruction.
If a positive result is obtained in step 1, the control board 45 moves the movable shutter 44 to a position where the light beam L2 for reading the regular reflection image is blocked (step 2).
When the movement of the movable shutter 44 is completed, the control device 21 moves the carriage 12 (see FIG. 3) along the platen glass 11 (see FIG. 3), and reads a diffuse reflection image. This reading operation corresponds to a diffuse reflection image reading mode.
FIG. 8 is a diagram illustrating the position of the movable shutter 44 during the diffuse reflection image reading mode. As shown in FIG. 8, the light beam L2 is blocked by the movable shutter 44 arranged on the optical path. As a result, only the light beam L1 illuminates the document reading position.

Returning to the description of FIG.
Next, the control board 45 determines whether the first scan has been completed (Step 3).
While a negative result is obtained in step 3, the control board 45 maintains the position of the movable shutter 44. This is because reading of the diffuse reflection image has not been completed.
If a positive result is obtained in step 3, the control board 45 moves the movable shutter 44 to a position where the light beam L1 for reading the diffuse reflection image is blocked (step 4).
When the movement of the movable shutter 44 ends, the control device 21 moves the carriage 12 along the platen glass 11 and executes reading of a regular reflection image. This reading operation corresponds to a regular reflection image reading mode.
FIG. 9 is a diagram illustrating the position of the movable shutter 44 during the regular reflection image reading mode. As shown in FIG. 9, the light beam L1 is blocked by a movable shutter 44 disposed on the optical path. As a result, only the light beam L2 illuminates the document reading position.

Returning to the description of FIG.
Next, the control board 45 determines whether or not the second scan is completed (Step 5).
While a negative result is obtained in step 5, the control board 45 maintains the position of the movable shutter 44. This is because reading of the regular reflection image has not been completed.
If a positive result is obtained in step 5, the control board 45 ends the reading operation.
In this operation example, the diffuse reflection image is read in the first scan, and the regular reflection image is read in the second scan. However, the reading order may be reversed. That is, the specular reflection image may be read in the first scan, and the diffuse reflection image may be read in the second scan.

<Operation example 2>
FIG. 10 is a flowchart illustrating another example of the control operation by the control board 45 (see FIG. 4). In FIG. 10, the parts corresponding to those in FIG. 7 are denoted by the same reference numerals. The symbol S in the figure means a step.
The feature of this operation example is that, after the determination in step 1, the determination of the high-light-amount reading mode (step 11) is performed.
The high-light-amount reading mode is an operation mode in which the amount of light irradiating the document is increased and the time required to read the diffuse reflection image is shortened, as compared with the case of the operation example 1 shown in FIG. The high light quantity reading mode is used for reading a document having a small gloss component. The high light amount reading mode is an example of a first operation mode.
The operation performed when a negative result is obtained in step 11 is the same as that of the operation example 1. That is, reading of the diffuse reflection image using only the light beam L1 and reading of the regular reflection image using only the light beam L2 are sequentially performed.

On the other hand, if a positive result is obtained in step 11, the control board 45 moves the movable shutter 44 to a position that does not block both the light beams L1 and L2 (step 12).
When the movement of the movable shutter 44 ends, the control device 21 moves the carriage 12 along the platen glass 11 and executes reading of the diffuse reflection image. This reading operation corresponds to the high light amount reading mode.
FIG. 11 is a view for explaining the position of the movable shutter 44 during the reading mode of the diffuse reflection image with a high light quantity. In the case of FIG. 11, the movable shutter 44 is retracted to a position that does not intersect with any of the optical paths of the light beams L1 and L2. Therefore, both the light beams L1 and L2 irradiate the reading position of the document.
As a result, the amount of light illuminating the reading position increases as compared with the case where only one of the light beams L1 and L2 is used. As a result, the amount of reflected light received by the light receiving unit 50 also increases. Therefore, even if the moving speed of the carriage 12 is increased as compared with the operation example 1, a sufficient amount of received light is ensured by the image sensor 52.

Returning to the description of FIG.
Next, the control board 45 determines whether or not the scanning by the high light quantity is completed (Step 13).
While a negative result is obtained in step 13, the control board 45 maintains the position of the movable shutter 44. That is, the state where both the light beams L1 and L2 irradiate the reading position is maintained.
If a positive result is obtained in step 13, the control board 45 ends the reading operation. As described above, the high-light-amount reading mode is used for reading a document having a small gloss component, and it is not necessary to obtain a regular reflection image. Thus, scanning in the high-light-amount reading mode only needs to be performed once.
However, after the reading in the high-light-amount reading mode is completed, the reading of the regular reflection image may be performed again.

<Operation example 3>
FIG. 12 is a flowchart illustrating another example of the control operation by the control board 45 (see FIG. 4). In FIG. 12, the parts corresponding to those in FIG. The symbol S in the figure means a step.
The feature of this operation example is that the determination of the mixed reading mode (step 21) is executed after the determination in step 1.
The mixed reading mode is an operation mode in which an image in which both the diffuse reflection light component and the regular reflection light component are mixed is read by one scanning.
The operation in the case where a negative result is obtained in step 21 is the same as the operation example 1. That is, reading of the diffuse reflection image using only the light beam L1 and reading of the regular reflection image using only the light beam L2 are sequentially performed.

On the other hand, if a positive result is obtained in step 21, the control board 45 moves the movable shutter 44 to a position where only a part of the light beam L2 is blocked (step 22).
When the movement of the movable shutter 44 is completed, the control device 21 (see FIG. 2) moves the carriage 12 (see FIG. 3) along the platen glass 11 (see FIG. 3), and adjusts the regular reflection image whose light amount is adjusted and the diffusion. The reading of the mixed image of the reflection images is executed. This reading operation corresponds to the mixed reading mode.

FIG. 13 is a diagram illustrating the position of the movable shutter 44 during the mixed reading mode. In the case of FIG. 13, the movable shutter 44 blocks only a part of the light beam L2. Therefore, all of the light beam L1 and a part of the light beam L2 irradiate the reading position of the document.
In this operation example, the light amount of the light beam L2 irradiating the reading position is set to 20% to 30% of the light amount of the light beam L2 emitted from the light guide member 42.
Because the light beam L1 is also incident on the reading position at the same time, if the light amount of the light beam L2 is too large, the reflected light amount from the reading position is too large, and the texture information such as glossiness is easily lost. If the amount of reflected light increases too much, it becomes difficult to see the change in the amount of reflected light due to gloss, and it is rather difficult to obtain a texture.

Returning to the description of FIG.
Next, the control board 45 determines whether the scanning is completed (Step 23).
While a negative result is obtained in step 23, the control board 45 maintains the position of the movable shutter 44. That is, the state where all of the light beam L1 and a part of the light beam L2 irradiate the reading position is maintained.
If a positive result is obtained in step 23, the control board 45 ends the reading operation. This is because in the mixed reading mode, in one scan, in addition to the diffuse reflection component mainly corresponding to the color component, both the regular reflection component mainly corresponding to the gloss component can be read. Thus, scanning in the mixed reading mode only needs to be performed once.

Note that the light amount of the light beam L2 for irradiating the original differs depending on the original to be read. Therefore, before the reading of the document is started, a preliminary scan for determining the light amount of the light beam L2 irradiating the document or the rate of blocking the light beam L2 may be performed.
When the light amount of the light beam L2 for irradiating the document or the light blocking ratio of the light beam L2 is determined by the preliminary scanning, the control board 45 adjusts the position at which the movable shutter 44 is stopped based on the result. Therefore, it is desirable that the stop position of the movable shutter 44 can be adjusted stepwise.
Note that the preliminary scanning may be performed a plurality of times under different conditions.

<Embodiment 2>
In the present embodiment, a case will be described in which a movable member is not used to shield light beams L1 and L2. Note that the overall configuration of the image forming apparatus 1 (see FIG. 1) is the same as that of the first embodiment.
FIG. 14 is a diagram illustrating a configuration example of an image reading device 10A used in the second embodiment. In FIG. 14, the parts corresponding to those in FIG. 3 are denoted by the same reference numerals.
The image reading device 10A shown in FIG. 14 uses a light source module 401.
The light source module 401 is provided with liquid crystal shutters 46A and 46B instead of the movable shutter 44 (see FIG. 3). The light source module 401 here is an example of an irradiation device.
The liquid crystal shutters 46A and 46B are optical elements whose transmission and non-transmission are switched by an electric signal or whose transmittance changes.

The liquid crystal shutter 46A is disposed at a position crossing the optical path of the light beam L2, and the liquid crystal shutter 46B is disposed at a position crossing the optical path of the light beam L1. When the entire liquid crystal shutter 46A is controlled to be in the non-transmissive state, the liquid crystal shutter 46A blocks the entire light beam L2. When the entire liquid crystal shutter 46B is controlled to be in the non-transmissive state, the liquid crystal shutter 46B blocks the entire light beam L1.
The liquid crystal shutter 46A can control only a part of the region to be in the non-transmissive state, and can control the remaining region to be in the transmissive state. In this case, the amount of light illuminating the reading position is determined by the ratio of the light beam L2 transmitted through the transmissive region and the light beam L2 blocked by the non-transmissive region.
However, the liquid crystal shutter 46A can switch between a state of transmitting 100% of the light L2, a state of transmitting 20% of the light L2, and a state of not transmitting the light L2, for example, by adjusting the transmittance. Of course, it is desirable that the transmittance can be adjusted in multiple stages, including a state of transmitting 10% and a state of transmitting 30%.

FIG. 15 is a diagram illustrating an example of an appearance of a light source module 401 used in the image reading device 10 according to the second embodiment. In FIG. 15, parts corresponding to those in FIG. 4 are denoted by reference numerals.
The liquid crystal shutters 46A and 46B have a strip shape extending in the axial direction of the light guide member 42. Further, the liquid crystal shutters 46A and 46B have a length sufficient to shield light beams L1 and L2 emitted from the light guide member 42.
The liquid crystal shutters 46A and 46B are attached to the housing 40A so as to block the optical paths of the light beams L1 and L2. That is, the liquid crystal shutters 46A and 46B are non-movable members.
Thus, the light source module 401 does not have the movable shutter 44 as in the first embodiment. For this reason, the reliability of the shutter operation by the light source module 401 is higher than that of the light source module 40 of the first embodiment.

The transmission characteristics of the liquid crystal shutters 46A and 46B are electrically controlled by the control board 45.
FIG. 16 is a diagram illustrating an example of control of the liquid crystal shutters 46A and 46B by the control board 45.
For example, in the case of the reading mode of the diffuse reflection image, the control board 45 controls the liquid crystal shutter 46A located on the optical path of the light beam L2 to be in a non-transmissive state, and sets the liquid crystal shutter 46B located on the optical path of the light ray L1 to be in a transmissive state. Control.
In the case of the regular reflection image reading mode, the control board 45 controls the liquid crystal shutter 46A located on the optical path of the light ray L2 to be in a transmissive state, and controls the liquid crystal shutter 46B located on the optical path of the light ray L1 to be in the non-transmissive state. To control.
Further, in the case of the high light quantity reading mode, the control board 45 controls both the liquid crystal shutter 46A located on the optical path of the light ray L2 and the liquid crystal shutter 46B located on the optical path of the light ray L1 to be in a transmitting state.

In the case of the mixed reading mode, the control board 45 controls only a part of the liquid crystal shutter 46A located on the optical path of the light beam L2 to be in a transmission state, and transmits the liquid crystal shutter 46B located on the optical path of the light beam L1. Control the state.
For example, only the 20% area of the liquid crystal shutter 46A is controlled to be transparent, and the remaining 80% area is controlled to be non-transparent.
Alternatively, as described above, the transmittance of the entire area of the liquid crystal shutter 46A may be controlled to 20%.

<Embodiment 3>
In the present embodiment, an example will be described in which the light guide members 42 are rotationally moved around an axis to emit the light beams L1 and L2. Note that the overall configuration of the image forming apparatus 1 (see FIG. 1) is the same as that of the first embodiment.
FIG. 17 is a diagram illustrating a configuration example of an image reading device 10B used in the third embodiment. In FIG. 17, the parts corresponding to those in FIG. 3 are denoted by the same reference numerals.
The image reading device 10B illustrated in FIG. 17 uses a light source module 411. The light source module 411 is an example of an irradiation device.

The light guide member 42 of the light source module 411 is different from the two light source modules 40 and 401 described above in that only the prism structure 42A is formed.
In the light source module 411, the light guide member 42 is attached to the housing 40A so as to be rotatable about its axis, and a drive mechanism 412 (see FIG. 18) for driving the light guide member 42 in the rotation direction is provided. ing. The movement of the drive mechanism 412 is controlled by the control board 45.

FIG. 18 is a diagram illustrating an example of an appearance of a light source module 411 used in the image reading device 10B according to the third embodiment. In FIG. 18, the parts corresponding to those in FIG.
In the case of the light source module 411, a drive mechanism 412 that rotationally drives the light guide member 42 is disposed inside the housing 40A. The drive mechanism 412 has, for example, a motor as a power source. The drive mechanism 412 is also provided with a connection mechanism for connecting the motor and the light guide member 42.
In the case of the present embodiment, the direction of the emitted light beam is switched according to the rotation angle of the light guide member 42. In addition, since the light guide member 42 in the present embodiment emits light rays in only one direction at a time, the light source module 411 cannot be used when a high light amount reading mode or a mixed reading mode is required. .

FIG. 19 is a diagram illustrating the positional relationship of the light guide member 42 when used in the diffuse reflection image reading mode.
In the case of FIG. 19, the surface on which the prism structure 42A is formed is located below the reflection mirror 43. For this reason, the illumination light reflected by the prism structure 42A is emitted to the reading position as a light ray L1.
FIG. 20 is a diagram illustrating the positional relationship of the light guide member 42 when used in the regular reflection image reading mode.
In the case of FIG. 20, the surface on which the prism structure 42A is formed is located at substantially the same height as the reflection mirror 43. Therefore, the illumination light reflected by the prism structure 42A is reflected by the reflection mirror 43, and thereafter, is emitted to the reading position as a light ray L2.

<Other embodiments>
Although the embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is apparent from the description of the appended claims that various modifications or improvements to the above-described embodiment are included in the technical scope of the present invention.

(1) In the first embodiment, the reflection mirror 43 (see FIG. 3) is arranged on the front side with respect to the normal axis of the reading position, but may be arranged on the rear side with respect to the normal axis.
FIG. 21 is a view for explaining an example in which the reflection mirror 43 is arranged on the rear side with respect to the normal axis of the reading position. In FIG. 21, parts corresponding to those in FIG. 11 are denoted by reference numerals.
In the case of the configuration shown in FIG. 21, the reflection mirror 43 may be attached so that the light beam L2 is incident on the document reading position at an incident angle of approximately 5 ° to approximately 10 °.
Although FIG. 21 illustrates the high-light-amount reading mode, operation in another reading mode is also possible.
Note that this configuration can be similarly applied to the third embodiment.

(2) In the first embodiment, only one reflection mirror 43 is used, but a plurality of reflection mirrors 43 may be used.
FIG. 22 is a diagram illustrating an example of the arrangement when two reflection mirrors 43A and 43B are used. In FIG. 22, parts corresponding to those in FIG. 11 are denoted by the same reference numerals.
The reflection mirror 43A is located on the front side of the normal axis of the original reading position, and the reflection mirror 43B is located on the rear side of the normal axis of the original reading position.
The reflection mirror 43A is an example of a first reflection member, and the reflection mirror 43B is an example of a second reflection member.

In the case of FIG. 22, the light beam L2 emitted from the light guide member 42 is split into two components, a component L21 reflected by the reflection mirror 43A and a component L22 reflected by the reflection mirror 43B.
Both the component L21 and the component L22 are incident on the document reading position at an incident angle of approximately 5 ° to approximately 10 °.
The reflection mirrors 43A and 43B are arranged so as not to prevent the light reflected at the reading position from entering the light receiving unit 50.
In the case of the arrangement shown in FIG. 22, even if the surface of the document has irregularities, the number of shadows appearing in the captured image is reduced.

(3) In the above embodiment, the case where the image reading apparatuses 10, 10A and 10B are used in the image forming apparatus 1 having the configuration shown in FIG. 1 has been described. Good.

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 10, 10A, 10B ... Image reading apparatus, 20 ... Image recording apparatus, 30 ... Paper tray, 40, 401, 411 ... Light source module, 41 ... Light source, 42 ... Light guide member, 42A, 42B ... Prism structure, 43, 43A, 43B reflection mirror, 44 movable shutter, 45 control board, 46A, 46B liquid crystal shutter, 412 drive mechanism

Claims (27)

A light source that outputs illumination light,
The illumination light propagating in the axial direction of the rod-shaped light guide member, the first illumination light incident on the reading position of the object to be imaged at a first angle from the side surface of the light guide member, and the first illumination light Emitting means for emitting as second illumination light incident at an angle different from the angle of 1;
Reflecting means for reflecting the second illumination light so as to be incident on the reading position at an incident angle smaller than the first illumination light with respect to a normal direction of the reading position of the object to be imaged;
Irradiation device having:   2. The control device according to claim 1, further comprising a control unit configured to control an optical switching of a relationship between a light amount of the first illumination light incident on the object and a light amount of the second illumination light incident on the object. An irradiation device according to claim 1.   The irradiation device according to claim 2, wherein the control unit changes a position of the light blocking unit.   The irradiation device according to claim 3, wherein the light shielding unit moves around the emission unit.   The irradiation device according to claim 2, wherein the control unit controls an optical element capable of electrically adjusting a transmitted light amount.   The irradiation device according to claim 5, wherein the optical element is a liquid crystal shutter, and the first illumination light and the second illumination light are arranged on an optical path leading to an object to be imaged.   The irradiation device according to claim 2, wherein the control unit does not block the first illumination light and blocks only a part of the second illumination light.   The irradiation device according to claim 1, wherein the emission unit switches between emission of the first illumination light and emission of the second illumination light by rotational movement.   The irradiation device according to claim 1, wherein the reflection unit is arranged at a position that is not on a normal line of a position where the second illumination light is incident on the object.   The irradiation apparatus according to claim 1, wherein the reflection unit is arranged at a position where the object does not obstruct the optical path of the reflected light reflecting the first illumination light or the second illumination light. The reflection means has a first reflection member and a second reflection member,
The first reflection member is disposed in a space closer to the emission unit than a normal line of a position where the second illumination light is incident on the object to be imaged,
The irradiation device according to claim 1, wherein the second reflection member is disposed in a space on the back side of the normal when viewed from the emission unit. A light source that outputs illumination light,
The illumination light propagating in the axial direction of the rod-shaped light guide member, the first illumination light incident on the reading position of the object to be imaged at a first angle from the side surface of the light guide member, and the first illumination light Emitting means for emitting as second illumination light incident at an angle different from the angle of 1;
Reflecting means for reflecting the second illumination light so as to be incident on the reading position at an incident angle smaller than the first illumination light with respect to a normal direction of the reading position of the object to be imaged;
Control means for controlling optical switching of the relationship between the amount of light that the first illumination light is incident on the object and the amount of light that the second illumination light is incident on the object;
A reading unit that receives reflected light from an object to be captured, converts the light into image data, and reads an image.   The control unit switches between a mode in which an image is read in a state where only the first illumination light is incident on the object and a mode in which an image is read in a state where only the second illumination light is incident on the object. The reading device according to claim 12.   The control unit reads an image in a state where only the first illumination light is incident on the object, a mode in which an image is read in a state where only the second illumination light is incident on the object, 13. The reading apparatus according to claim 12, wherein the reading apparatus switches between a mode in which an image is read in a state where both the first illumination light and the second illumination light are incident on the object.   13. The reading apparatus according to claim 12, wherein the control unit controls so that the entirety of the first illumination light and a part of the second illumination light are mixed and incident on the object.   In a mode in which only the first illumination light is made incident on the object and light reflected from the object is read and an image is read, the control unit sets the light shielding unit to a position where the second illumination light is shielded. In the mode in which only the second illumination light is made incident on the object and the reflected light of the object is received and the image is read, the position at which the first illumination light is shielded by the light-shielding means. The reading device according to claim 12, wherein the reading device is moved.   In a mode in which both the first illuminating light and the second illuminating light are made incident on the object and the image of the object is read, the control unit controls the light-shielding unit with the first illumination light. 17. The reading device according to claim 16, wherein both of the second illumination light are moved to a position where light is not blocked.   In a mode in which all of the first illumination light and a part of the second illumination light are mixed and made incident on the object to read an image of the object, the control unit may control the light shielding unit. The reading device according to claim 16, wherein the reading device is moved to a position where only a part of the second illumination light is shielded.   The reading device according to claim 12, wherein the reflected light of the imaging object with respect to the second illumination light includes a component related to a texture of the imaging object.   17. The reader according to claim 16, further comprising a variable mechanism that changes a position of the light shielding unit.   13. The reader according to claim 12, further comprising an optical element capable of electrically adjusting the amount of transmitted light.   22. The reading device according to claim 21, wherein the optical element is a liquid crystal shutter, and the first illumination light and the second illumination light are respectively arranged on an optical path leading to an object to be imaged.   23. The reading device according to claim 22, wherein the liquid crystal shutter does not block the first illumination light and blocks only a part of the second illumination light. 13. The reading apparatus according to claim 12, wherein the emission unit switches between emission of the first illumination light and emission of the second illumination light by rotating.   The reading device according to claim 12, wherein the reflection unit is arranged at a position that is not on a normal line of a position where the second illumination light is incident on the object.   The reading device according to claim 12, wherein the reflection unit is arranged at a position where the object does not obstruct an optical path of reflected light that reflects the first illumination light or the second illumination light. The reflection means has a first reflection member and a second reflection member,
The first reflection member is disposed in a space closer to the emission unit than a normal line of a position where the second illumination light is incident on the object to be imaged,
13. The reading device according to claim 12, wherein the second reflection member is disposed in a space on the back side with respect to the normal when viewed from the emission unit.