Discrimination device and image forming device

Abstract

To discriminate between paper on which coating processing is performed for suppressing glossiness of the paper surface and paper on which the processing is not performed.SOLUTION: A discrimination device includes: a processor used for discriminating between first paper on which coating processing is performed for suppressing glossiness of the paper surface and second paper on which the processing is not performed; a light source 30 for irradiating the surface of paper P with light; a first light detector 31 for detecting the light reflected on the surface of the paper P; and second light detector 32 provided at a position different from the first light detector 31, and for detecting diffuse reflection light. The first light detector 31 is positioned in the direction deviated by a certain angle θ2 with respect to a regular reflection direction of light. The processor acquires a light quantity ratio which is the ratio of light quantity detected by the first light detector 31 and light quantity detected by the second light detector 32, and determines whether the paper P is the first paper or the second paper according to the relation between the light quantity ratio and a threshold value determined beforehand.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a discrimination device and an image forming apparatus. [Background technology]

[0002] There is known a media sensor device that automatically identifies the type of paper by reading the paper used for printing with a sensor. An image forming device is controlled based on the paper type identified by the media sensor device. For example, operations related to paper transport in the image forming device, a transfer device, a fixing device, etc. are controlled according to the paper type. This allows printing suited to the paper type to be achieved, resulting in the desired printed matter.

[0003] Patent Document 1 discloses a recording medium smoothness detection device that detects the smoothness of the surface of a recording medium. The document also describes setting printing conditions for an image forming device based on the detected smoothness. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2015-215338 A Summary of the Invention [Problem to be solved by the invention]

[0005] It is desirable to be able to distinguish between paper that has been coated to reduce the gloss of its surface and paper that has not been coated.

[0006] To provide a discrimination device for discriminating between paper that has been coated to reduce the gloss of the paper surface and paper that has not been coated, or an image forming apparatus equipped with the discrimination device. [Means for solving the problem]

[0007] The invention of claim 1 is a discrimination device comprising: a processor used to discriminate between a first paper which has been coated to reduce the gloss of its surface and a second paper which has not been coated to reduce the gloss of its surface; a light source which irradiates light onto the surface of the paper; a first photodetector which detects the light reflected by the surface of the paper; and a second photodetector which is provided at a position separate from the first photodetector and detects diffuse reflection of the light reflected by the surface of the paper, wherein the first photodetector is located in a direction shifted by a certain angle from the direction of direct reflection of the light reflected by the surface of the paper, and the processor obtains a light intensity ratio which is the ratio between the amount of light detected by the first photodetector and the amount of light detected by the second photodetector, and discriminates whether the paper is the first paper or the second paper depending on the relationship between the light intensity ratio and a predetermined threshold value.

[0008] The invention according to claim 2 is the discrimination device according to claim 1, wherein the second photodetector is positioned in a normal direction to the surface of the paper.

[0009] The invention of claim 3 is the discrimination device described in claim 1, wherein the first photodetector is positioned in a direction shifted by approximately 20 degrees from the direct reflection direction of the light reflected by the surface of the paper.

[0010] The invention according to claim 4 is an image forming apparatus including the discrimination device according to any one of claims 1 to 3.

[0011] The invention of claim 5 is a discrimination device comprising: a processor used to discriminate between a first paper which has been coated to reduce the gloss of its surface and a second paper which has not been coated to reduce the gloss of its surface; a light source which irradiates light onto the surface of the paper; a first photodetector which detects the light reflected by the surface of the paper; and a second photodetector which is provided at a position separate from the first photodetector and detects diffuse reflected light of the light reflected by the surface of the paper, wherein the first photodetector is located in a direction shifted by a certain angle from the direction of direct reflection of the light reflected by the surface of the paper, and the processor obtains a light intensity difference which is the difference between the amount of light detected by the first photodetector and the amount of light detected by the second photodetector, and discriminates whether the paper is the first paper or the second paper depending on the relationship between the light intensity difference and a predetermined threshold value.

[0012] The invention according to claim 6 is the discrimination device according to claim 5, wherein the second photodetector is positioned in a normal direction to the surface of the paper.

[0013] The invention of claim 7 is the discrimination device described in claim 5, wherein the first photodetector is positioned in a direction shifted by approximately 20 degrees from the direct reflection direction of the light reflected by the surface of the paper.

[0014] The invention according to claim 8 is an image forming apparatus including the discrimination device according to any one of claims 5 to 7. Effect of the Invention

[0015] According to the invention as defined in claim 1 or 5, it is possible to distinguish between paper that has been coated to reduce the gloss of the paper surface and paper that has not been coated.

[0016] According to the invention as defined in claim 2 or 6, even if the incident angle (angle other than 0 degrees) of the light from the light source changes, the diffusely reflected light is detected by the second photodetector.

[0017] According to the invention as defined in claim 3 or 7, the accuracy of distinguishing between the first and second papers is improved compared to a case where the first photodetector is not positioned in a direction shifted by approximately 20 degrees from the direction of specular reflection of light.

[0018] According to the invention as defined in claim 4 or 8, the first and second paper discrimination results can be used in the main body of the image forming apparatus. [Brief description of the drawings]

[0019] [Figure 1] 1 is a diagram showing a configuration of an image forming apparatus according to an embodiment; [Diagram 2] 1 is a functional block diagram of an image forming apparatus according to an embodiment; [Diagram 3] FIG. 1 is a diagram illustrating a configuration of a sensor device according to an embodiment. [Figure 4] FIG. 13 is a diagram showing the light amount ratio (a) obtained by dividing the amount of light received according to the light receiving angle of (a) plain paper and (b) matte coated paper when the light incident angle is 70 degrees by the amount of light received at a light receiving angle of 0 degrees. [Diagram 5] 10 is a flowchart showing a process for distinguishing between matte coated paper and plain paper. [Figure 6] 13 is a flowchart showing another discrimination process between matte coated paper and plain paper. [Figure 7] FIG. 2 is a diagram illustrating an example of a hardware configuration of a computer. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] <Summary> Hereinafter, the embodiments of the present invention will be described in detail with reference to the accompanying drawings. The configurations described below are illustrative examples and can be modified as appropriate. In addition, when multiple embodiments or modifications are included below, it is assumed from the beginning that the characteristic parts of the embodiments or modifications will be used in appropriate combination. In all drawings, the same or similar elements are given the same reference numerals, and duplicated descriptions will be omitted.

[0021] The following describes a discrimination device that discriminates between a first paper that has been coated to reduce the gloss of the paper surface and a second paper that has not been coated in this manner, or an image forming apparatus equipped with the same.

[0022] The first paper that has been coated to reduce the gloss of its surface may be, for example, matte coated paper or a similar paper, etc. The second paper that has not been coated to reduce the gloss of its surface may be, for example, plain paper or a similar paper, etc.

[0023] The light source may be, for example, a light emitting diode (LED), a laser diode (LD), a vertical cavity surface emitting laser (VCSEL), or the like.

[0024] The light detector may be, for example, a photodiode.

[0025] For example, the discrimination device may be composed of only a sensor device separated from the main body of the image forming apparatus, or may be composed of a sensor device and the main body of the image forming apparatus in combination. Furthermore, the discrimination device may be provided in the paper transport path of the image forming apparatus.

[0026] The discrimination device may execute a discrimination process for another paper type at least either before or after executing the discrimination process for the paper type described below.

[0027] The image forming apparatus may be, for example, an apparatus that prints on a recording medium using a printing method such as an electrophotographic method, an inkjet method, offset printing, gravure printing, etc. The image forming apparatus may apply image forming conditions corresponding to the paper identified by the identification device to devices and parts related to image formation, and execute a printing process on the paper.

[0028] <Embodiment> In the following, an embodiment will be described in which a distinction is made between matte coated paper, which is paper that has been subjected to a coating process to reduce the gloss of the paper surface, and plain paper, which is paper that has not been subjected to such a coating process.

[0029] Fig. 1 is a diagram showing a configuration of an image forming apparatus 10 according to an embodiment. Fig. 2 is a functional block diagram of the image forming apparatus 10. The image forming apparatus 10 includes a main body 12 and a sensor device 16.

[0030] The main body 12 of the image forming apparatus 10 is a device that forms an image based on image information obtained from a computer (not shown) such as a PC connected thereto. In this embodiment, the main body 12 of the image forming apparatus 10 is an electrophotographic printing device. The main body 12 of the image forming apparatus 10 includes a control device 50, a conveying device 52, a transfer device 54, and a fixing device 56.

[0031] 1, the sensor device 16 has an insertion opening 20 through which the paper P is inserted. The sensor device 16 is a device that detects the properties of the paper P inserted into the insertion opening 20. The sensor device 16 is connected to the main body 12 of the image forming apparatus 10 via a cable 40. The cable 40 supplies power from the main body 12 to the sensor device 16, and transmits information about the paper detected by the sensor device 16 to a control device 50 of the main body 12.

[0032] 2, the sensor device 16 includes a control device 24, a light source 30, and first to third photodetectors 31, 32, and 33. The control device 24 may include, for example, a microcontroller. The light source 30 is an LED. The first to third photodetectors 31, 32, and 33 are photodiodes, respectively.

[0033] The control device 24 controls the light source 30 according to commands from the control device 50 of the main body 12 or a computer (not shown) such as a PC connected to the main body 12 via the cable 40. The control device 24 then irradiates light from the light source 30 onto the paper P and obtains detection values ​​from the first to third photodetectors 31, 32, and 33. The control device 24 then transmits each of the obtained detection values ​​to the control device 50 of the main body 12. The control device 50 of the main body 12 determines the type of the paper P based on each of the detection values ​​from the control device 24 and threshold values ​​previously stored in a storage device within the control device 50. In this way, the sensor device 16 and the control device 50 of the main body 12 function as a paper type determination device 14.

[0034] An example of the operation of the image forming apparatus 10 to form an image will be described below. First, image information input from a computer such as a PC connected to the main body 12 is stored in a storage device in the control device 50. The user sets paper P in the insertion port 20 of the sensor device 16, determines the type of paper P, and then sets the paper P in a paper feed cassette of the main body 12.

[0035] As described above, the control device 50 of the main body 12 determines the type of the paper P based on the information sent from the sensor device 16. The control device 50 stores image formation conditions for each type of paper P. The image formation conditions are, for example, conditions related to the control of the conveying device 52, the transfer device 54, the fixing device 56, and the like. The control device 50 feeds the paper P from the paper feed cassette and performs printing processing according to the image information. At this time, the control device 50 applies the image formation conditions associated with the determined paper P to at least one of the conveying device 52, the transfer device 54, and the fixing device 56, and performs printing processing on the paper P. For example, in the transfer device 54, a secondary transfer voltage, which is an example of an image formation condition, is controlled according to the determined paper type.

[0036] Next, the discrimination between matte coated paper and plain paper will be specifically described. The discrimination device 14 has a function of discriminating between matte coated paper and plain paper. Fig. 3 is a diagram showing a schematic configuration of the sensor device 16. As described above, the sensor device 16 includes the light source 30 and the first to third photodetectors 31, 32, and 33.

[0037] The light source 30 emits light with an incident angle θ1. In this embodiment, θ1 is 70 degrees. Note that θ1 may be changed as appropriate.

[0038] The first photodetector 31 is positioned in a direction shifted by a certain angle θ2 from the direction of specular reflection of the light of the light source 30 reflected by the surface of the paper P. The third photodetector 33 is positioned in the direction of specular reflection of the light of the light source 30. In this embodiment, θ2 is 20 degrees.

[0039] The second photodetector 32 is positioned in the normal direction to the surface of the paper P. The second photodetector 32 detects diffuse reflected light of light reflected by the surface of the paper P. To distinguish between matte coated paper and plain paper, the light source 30 and the first and second photodetectors 31 and 32 are used.

[0040] Here, the principle of the method for distinguishing between matte coated paper and plain paper will be described. FIG. 4 is a diagram showing the light amount ratio (a) of plain paper and (b) of matte coated paper divided by the light amount at a light receiving angle of 0 degrees when the light incident angle is 70 degrees. The horizontal axis of the graphs in FIG. 4(a) and (b) is the light receiving angle, and the vertical axis is the light amount ratio. Note that the light receiving angle is expressed as a negative value when the normal direction to the surface of the paper P is 0 degrees, and the inclination angle toward the light source 30 side is expressed as a positive value when the inclination angle toward the specular reflection direction side. In FIG. 4, the light receiving angle of 70 degrees is the specular reflection direction. Each of the multiple lines in FIG. 4(a) and (b) shows the results of one type of paper. That is, the multiple lines in FIG. 4(a) show the results of multiple types of plain paper, and the multiple lines in FIG. 4(b) show the results of multiple types of matte coated paper.

[0041] As can be seen from Figure 4, the difference in the amount of light received between plain paper and matte coated paper is most apparent near a light receiving angle of 50 degrees, which is about 20 degrees off from the direction of specular reflection (light receiving angle of 70 degrees). At a light receiving angle of about 50 degrees, plain paper obtains a relatively high amount of light received, while matte coated paper obtains a relatively low amount of light received that is close to the amount of light received at a light receiving angle of 0 degrees. Therefore, by acquiring the amount of light at a position that is about 20 degrees off from the direction of specular reflection, it is possible to distinguish between matte coated paper and plain paper based on that amount of light. Based on this principle, this embodiment distinguishes between these papers.

[0042] 3, the light source 30 emits light with an incident angle of 70 degrees. The first photodetector 31 is positioned in a direction shifted by 20 degrees from the specular reflection direction of the light from the light source 30 (acceptance angle of 70 degrees), i.e., in a direction with an acceptance angle of 50 degrees. The second photodetector 32 is positioned in a direction with an acceptance angle of 0 degrees.

[0043] The first photodetector 31 is preferably positioned in a direction shifted by 20 degrees or a close angle (approximately 20 degrees) from the direction of specular reflection of light. This is expected to enable relatively high accuracy in distinguishing between matte coated paper and plain paper. However, the position of the first photodetector 31 is not limited to that direction. The first photodetector 31 may be provided in a position where a higher amount of reflected light is received when the paper P is plain paper compared to when the paper P is matte coated paper. The first photodetector 31 may be positioned on the normal side of the direction of specular reflection of light (the direction in which the third photodetector 33 is positioned) as shown in FIG. 3, or may be positioned on the paper P side of the direction of specular reflection of light.

[0044] As described above, the second photodetector 32 is located in the normal direction to the surface of the paper P. However, the position of the second photodetector 32 is not limited to that direction. The second photodetector 32 only needs to be provided in a position where it can detect the amount of diffusely reflected light from the paper P.

[0045] 5 is a flow chart showing the process of distinguishing between matte coated paper and plain paper. In step S100, the control device 24 of the sensor device 16 irradiates light from the light source 30 onto the paper P. In step S102, the control device 24 obtains the detection value of the first photodetector 31 as the first light amount. In step S104, the control device 24 obtains the detection value of the second photodetector 32 as the second light amount. Then, the control device 24 transmits the first and second light amounts to the main body 12 of the image forming apparatus 10. The control device 50 of the main body 12 receives the first and second light amounts.

[0046] In step S106, the control device 50 of the main body 12 divides the first light amount by the second light amount to calculate a light amount ratio (=first light amount / second light amount). Next, in step S108, the control device 50 checks whether the light amount ratio is equal to or greater than a predetermined threshold value Rth stored in its own storage device.

[0047] If step S108 is Yes, in step S110, the control device 50 determines that the paper P is plain paper. On the other hand, if step S108 is No, in step S112, the control device 50 determines that the paper P is matte coated paper.

[0048] According to the embodiment described above, matte coated paper and plain paper are distinguished.

[0049] 5, the light amount ratio is calculated by using the second light amount as the denominator and the first light amount as the numerator. However, the light amount ratio may be calculated by using the first light amount as the denominator and the second light amount as the numerator (light amount ratio=second light amount / first light amount). In this case, in step S108, if the light amount ratio is equal to or less than the threshold, the control device 50 determines that the paper P is plain paper, and if not, determines that the paper P is matte coated paper.

[0050] <Another embodiment> Next, another process for distinguishing between matte coated paper and plain paper will be described. Fig. 6 is a flowchart showing another process for distinguishing between matte coated paper and plain paper. Steps S200 to S204 in Fig. 6 are the same as steps S100 to S104 in Fig. 5. Steps S206 and after in Fig. 6 are different from the flowchart in Fig. 5.

[0051] In step S206, the control device 50 of the main body 12 calculates the light amount difference (=first light amount-second light amount) by subtracting the second light amount from the first light amount. Next, in step S208, the control device 50 checks whether the light amount difference is equal to or greater than a predetermined threshold value Dth stored in its own storage device.

[0052] If step S208 is Yes, then in step S210, the control device 50 determines that the paper P is plain paper. On the other hand, if step S208 is No, then in step S212, the control device 50 determines that the paper P is matte coated paper.

[0053] In the other embodiment described above, the matte coated paper and the plain paper are also distinguished.

[0054] 6, the light amount difference is obtained by subtracting the second light amount from the first light amount. However, the light amount difference may be obtained by subtracting the first light amount from the second light amount (light amount difference=second light amount-first light amount). In this case, in step S208, if the light amount difference is equal to or less than the threshold, the control device 50 will determine that the paper P is plain paper, and if not, will determine that the paper P is matte coated paper.

[0055] In the embodiment described above, matte coated paper and plain paper are distinguished from each other based on the first and second light quantities. However, the distinction may be made without using the second light quantity. In this case, for example, the control device 50 may distinguish the paper P as plain paper if the first light quantity is equal to or greater than a predetermined threshold value, and may distinguish the paper P as matte coated paper if the first light quantity is not equal to or greater than a predetermined threshold value.

[0056] <Control device configuration> The control device of the above embodiment may be configured using a computer. The control device may be constructed as, for example, a single computer or a system consisting of multiple computers linked to each other. As illustrated in FIG. 7, the computer that is the base of the control device has a circuit configuration in which, for example, a processor 1002, a memory (main storage device) 1004 such as a random access memory (RAM), a controller that controls an auxiliary storage device 1006 that is a non-volatile storage device such as a flash memory, an SSD (solid state drive), or an HDD (hard disk drive), an interface with various input / output devices 1008, a network interface 1010 that controls connection to a network, and the like are connected via a data transmission path such as a bus 1012. A program in which the processing contents are described is installed in the computer via a network or the like and stored in the auxiliary storage device 1006. The program stored in the auxiliary storage device 1006 is executed by the processor 1002 using the memory 1004, thereby configuring the control device of this embodiment.

[0057] The above program can be provided via a network such as the Internet, or can be provided by storing it on a computer-readable recording medium such as an optical disk or a USB memory.

[0058] In the above embodiment, the term "processor" refers to a processor in a broad sense, including general-purpose processors (e.g., CPU: Central Processing Unit, etc.) and dedicated processors (e.g., GPU: Graphics Processing Unit, ASIC: Application Specific Integrated Circuit, FPGA: Field Programmable Gate Array, programmable logic device, etc.).

[0059] In addition, the operations of the processors in the above embodiments may be performed not only by one processor, but also by multiple processors located at physically separate locations working together. Furthermore, the order of the operations of the processors is not limited to the order described in the above embodiments, and may be changed as appropriate.

[0060] (Additional Note) (((1))) a processor for discriminating between a first paper having a coating that reduces the gloss of the paper surface and a second paper having no coating that reduces the gloss of the paper surface; A light source that irradiates light onto a surface of the paper; a first photodetector for detecting the light reflected from a surface of the paper; a second photodetector provided at a position separate from the first photodetector and configured to detect diffuse reflected light of the light reflected by the surface of the paper; the first photodetector is positioned in a direction offset by a certain angle with respect to a direction of specular reflection of the light reflected by the surface of the paper; The processor, A light amount ratio is obtained, which is a ratio between the amount of light detected by the first photodetector and the amount of light detected by the second photodetector; determining whether the paper is the first paper or the second paper according to a relationship between the light amount ratio and a predetermined threshold value; Discrimination device. (((2))) The discrimination device according to (((1)), The second photodetector is positioned normal to the surface of the paper. Discrimination device. (((3))) The discrimination device according to (((1))) or (((2)), The first photodetector is positioned in a direction shifted by approximately 20 degrees from the direction of specular reflection of the light reflected by the surface of the paper. Discrimination device. (((4))) A discrimination device according to any one of ((1))) to (((3))), Image forming device. (((5))) a processor for discriminating between a first paper having a coating that reduces the gloss of the paper surface and a second paper having no coating that reduces the gloss of the paper surface; A light source that irradiates light onto the surface of the paper; a first photodetector for detecting the light reflected from a surface of the paper; a second photodetector provided at a position separate from the first photodetector and configured to detect diffuse reflected light of the light reflected by the surface of the paper; the first photodetector is positioned in a direction offset by a certain angle with respect to a direction of specular reflection of the light reflected by the surface of the paper; The processor, A light amount difference between the amount of light detected by the first photodetector and the amount of light detected by the second photodetector is obtained; determining whether the paper is the first paper or the second paper according to a relationship between the light amount difference and a predetermined threshold value; Discrimination device. (((6))) The discrimination device according to (((5))), The second photodetector is positioned normal to the surface of the paper. Discrimination device. (((7))) The discrimination device according to ((5))) or ((6)), The first photodetector is positioned in a direction shifted by approximately 20 degrees from the direction of specular reflection of the light reflected by the surface of the paper. Discrimination device. (((8))) A discrimination device according to any one of ((5))) to (((7))), Image forming device.

[0061] According to the invention of (((1))) or (((5))), it is possible to distinguish between paper that has been coated to reduce the gloss of the paper surface and paper that has not been coated. According to the invention related to (((2))) or (((6))), even if the incident angle of the light from the light source (an angle other than 0 degrees) changes, the diffuse reflected light is detected by the second photodetector. According to the invention relating to (((3))) or (((7))), the accuracy of distinguishing between the first and second papers is improved compared to a case where the first photodetector is not positioned in a direction shifted by approximately 20 degrees from the direction of specular reflection of light. According to the invention related to (((4))) or (((8))), the results of the first and second paper discrimination can be used in the main body of the image forming apparatus. [Explanation of symbols]

[0062] 10 image forming apparatus, 12 main body, 14 discrimination device, 16 sensor device, 20 insertion port, 24 control device, 30 light source, 31 first photodetector, 32 second photodetector, 33 third photodetector, 50 control device, 52 conveying device, 54 transfer device, 56 fixing device, 40 cable, 1002 processor, 1004 memory, 1006 auxiliary storage device, 1008 input / output device, 1010 network interface, 1012 bus, P paper.

Claims

1. a processor for discriminating between a first paper having a coating that reduces the gloss of the paper surface and a second paper having no coating that reduces the gloss of the paper surface; A light source that irradiates light onto the surface of the paper; a first photodetector for detecting the light reflected from a surface of the paper; a second photodetector provided at a position separate from the first photodetector and configured to detect diffuse reflected light of the light reflected by a surface of the paper; the first photodetector is positioned in a direction offset by a certain angle with respect to a direction of specular reflection of the light reflected by the surface of the paper; The processor, acquiring a light amount ratio that is a ratio between the amount of light detected by the first photodetector and the amount of light detected by the second photodetector; determining whether the paper is the first paper or the second paper according to a relationship between the light amount ratio and a predetermined threshold value; Discrimination device.

2. The discrimination device according to claim 1, The second photodetector is positioned normal to the surface of the paper. Discrimination device.

3. The discrimination device according to claim 1, The first photodetector is positioned in a direction shifted by approximately 20 degrees from the direction of specular reflection of the light reflected by the surface of the paper. Discrimination device.

4. A device comprising the discrimination device according to any one of claims 1 to 3. Image forming device.

5. a processor for discriminating between a first paper having a coating that reduces the gloss of the paper surface and a second paper having no coating that reduces the gloss of the paper surface; A light source that irradiates light onto the surface of the paper; a first photodetector for detecting the light reflected from a surface of the paper; a second photodetector provided at a position separate from the first photodetector and configured to detect diffuse reflected light of the light reflected by a surface of the paper; the first photodetector is positioned in a direction offset by a certain angle with respect to a direction of specular reflection of the light reflected by the surface of the paper; The processor, A light amount difference between the amount of light detected by the first photodetector and the amount of light detected by the second photodetector is obtained; determining whether the paper is the first paper or the second paper according to a relationship between the light amount difference and a predetermined threshold value; Discrimination device.

6. The discrimination device according to claim 5, The second photodetector is positioned normal to the surface of the paper. Discrimination device.

7. The discrimination device according to claim 5, The first photodetector is positioned in a direction shifted by approximately 20 degrees from the direction of specular reflection of the light reflected by the surface of the paper. Discrimination device.

8. A device comprising the discrimination device according to any one of claims 5 to 7. Image forming device.

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