Media detection device, image forming system, media detection program, and process condition control program

Abstract

To more accurately detect moisture information corresponding to the amount of moisture or percentage of moisture in a sheet.SOLUTION: A medium detection device (detector 20) is to detect moisture information corresponding to the amount of moisture or percentage of moisture in a sheet, and the medium detection device comprises: a light-emitting unit (first light-emitting unit 231 and second light-emitting unit 232) that radiates light; a light receiving unit 233 that receives the light reflected on the sheet or the light transmitted through the sheet; and a moisture information control unit (detection control unit 21) that determines the moisture information based on temperature information corresponding to the temperature of the medium detection device and output from the light receiving unit 233.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a media detection device, an image forming system, a media detection program, and a process condition control program. [Background technology]

[0002] Conventionally known image forming devices have a media sensor installed in the middle of a paper transport path, and the media sensor detects characteristic values ​​of the paper transported along the transport path. The image forming device then determines image formation conditions in accordance with the characteristic values ​​of the paper detected by the media sensor, and forms an image on the paper.

[0003] For example, in Patent Document 1, a moisture sensor having a light-emitting part including an LED (Light Emittng Diode) and a light-receiving part including a PD (PhotoDiode) is installed to measure the moisture content of paper. Moisture information It is described that the moisture content is measured. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-057513 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, when such a moisture sensor is used to measure the moisture content of paper, it has been found that the measurement results can change even if the paper is in the same condition.For example, when measuring the moisture content while continuously passing paper through during a job, the moisture content changes even though the paper is in the same condition, resulting in an error in the measured moisture content of the actual paper.

[0006] The object of the present invention is to WaterIt is an object of the present invention to provide a media detection device, an image forming system, a media detection program, and a process condition control program that are capable of detecting media information with higher accuracy. [Means for solving the problem]

[0007] In order to solve the above problem, the media detection device according to claim 1 comprises: A media detection device for detecting moisture information of a paper sheet, comprising: A light emitting unit that emits light; a light receiving section that receives the light reflected by the paper or transmitted through the paper; The above Light-emitting part a moisture information control unit that determines the moisture information based on temperature information corresponding to the temperature and an output of the light receiving unit; Equipped with.

[0009] Claim 2 The present invention provides a media detection device according to claim 1, The light emitting section includes a first light emitting section and a second light emitting section for emitting light of wavelengths having different moisture absorption rates.

[0010] Claim 3 The invention described in claim 2 In the media detection device according to the The first light emitting unit emits a reference light, the second light-emitting unit emits light having a wavelength that is more absorbed by moisture than the reference light, The moisture information control unit determines the moisture information based on the temperature information and an output of the light receiving unit in response to the reference light and the light emitted by the second light emitting unit.

[0011] Claim 4 The invention described in claim 3 In the media detection device according to the The moisture information control unit determines the moisture information based on the temperature information and a ratio of an output of the light receiving unit to the reference light and the light emitted by the second light emitting unit.

[0012] Claim 5 The invention described in claim 3 In the media detection device according to the The moisture information control unit determines the moisture information based on temperature information corresponding to the temperature of the second light-emitting unit and an output of the light-receiving unit.

[0013] Claim 6 The present invention provides a media detection device according to claim 1, The above Light-emitting part Equipped with a temperature detection sensor that detects the temperature of The above Light-emitting part The temperature information corresponding to the temperature is temperature information corresponding to the detection result of the temperature detection sensor.

[0014] Claim 7 The present invention provides a media detection device according to claim 1, The moisture information control unit determines the moisture information while the paper is being transported.

[0015] Claim 8 The invention described in claim 7 In the media detection device according to the The moisture information control unit determines the moisture information for each of the sheets.

[0016] Claim 9 The invention described in claim 7 In the media detection device according to the The moisture information control unit determines the moisture information multiple times for one sheet of paper.

[0017] Claim 10 The invention described in claim 7 In the media detection device according to the The moisture information control unit determines the moisture information based on the temperature information detected during sheet transport and an output from the light receiving unit.

[0018] Claim 11The present invention provides a media detection device according to claim 1, The light emitting unit and the light receiving unit are included in a first media sensor. Can .

[0019] Claim 12 The invention described in claim 11 In the media detection device according to the The first media sensor is disposed on a transport path of the paper.

[0020] Claim 13 The invention described in claim 12 In the media detection device according to the The first media sensor is disposed on a transport path of the paper for transporting the paper to an image forming unit capable of forming an image on the paper.

[0021] Claim 14 The present invention provides a media detection device according to claim 1, The moisture information control unit determines provisional moisture information based on the output of the light receiving unit, Light-emitting part The moisture information is determined by correcting the provisional moisture information based on temperature information corresponding to the temperature of the sample.

[0022] Claim 15 The invention described in claim 14 In the media detection device according to the The moisture information control unit obtains information about a wavelength of light emitted by the light-emitting unit based on the temperature of the light-emitting unit, and corrects the provisional moisture information based on the obtained wavelength information.

[0023] Claim 16 The invention described in claim 14 In the media detection device according to the The above Light-emitting part Equipped with a temperature detection sensor that detects the temperature of The moisture information control unit corrects the provisional moisture information to be lower when the temperature detected by the temperature detection sensor is higher than a reference temperature, and corrects the provisional moisture information to be higher when the detected temperature is lower than the reference temperature.

[0024] Claim 17 The present invention provides a media detection device according to claim 1, The light emitting portion includes an LED (Light Emitting Diode).

[0025] Claim 18 The invention described in claim 6 In the media detection device according to the The temperature detection sensor is disposed in contact with a member supporting the light emitting unit.

[0026] Claim 19 The invention described in claim 6 In the media detection device according to the The temperature detection sensor is disposed opposite to and in no contact with the light emitting portion.

[0027] Claim 20 The present invention provides a media detection device according to claim 1, The moisture information control unit is the temperature information, the output of the light receiving unit, and The moisture information is determined based on the paper type of the paper.

[0028] Claim 21 The invention described in claim 20 In the media detection device according to the a second media sensor for detecting a physical property corresponding to the paper type; a paper type determination unit that determines the paper type based on a detection result of the second media sensor; Equipped with.

[0029] Claim 22 The invention described in claim 21 In the media detection device according to the The second media sensor is a basis weight sensor.

[0030] Claim 23 The image forming system according to From claim 1 22 The media detection device according to any one of claims 1 to 5, an image forming unit capable of forming an image on the paper; An image forming system comprising: The image forming apparatus further includes a process condition control unit that determines process conditions for image formation in the image forming unit based on the moisture information determined by the moisture information control unit.

[0031] Claim 24 The invention described in claim 23 In the image forming system according to the present invention, The process conditions include transfer conditions.

[0032] Claim 25 The invention described in claim 24 In the image forming system according to the present invention, The transfer conditions include a transfer current and a transfer voltage.

[0033] Claim 26 The image forming system according to an image forming unit that forms an image on a sheet; a media detection device for detecting moisture information of the paper; a process condition control unit that determines process conditions in the image forming unit; Equipped with The media detection device includes a light emitting unit that irradiates light, and a light receiving unit that receives the light reflected by the paper or transmitted through the paper. a moisture information control unit that determines the moisture information based on temperature information corresponding to the temperature of the light-emitting unit and an output of the light-receiving unit; having The process condition control unit The moisture information determined by the moisture information control unit The process conditions are determined based on the above.

[0034] Claim 27 The media detection program described in A media detection program for detecting moisture information of paper, On the computer, A media detection device having a light emitting section that irradiates light and a light receiving section that receives the light reflected by the paper or transmitted through the paper. The light emitting unit in acquiring temperature information corresponding to the temperature of The above Light-emitting part a moisture information determination step of determining the moisture information based on temperature information corresponding to the temperature and an output of the light receiving unit; It is possible to execute the following.

[0035] The process condition control program according to claim 28, A process condition control program for determining process conditions for forming an image on a sheet in an image forming unit, On the computer, A media detection device having a light emitting section that irradiates light and a light receiving section that receives the light reflected by the paper or transmitted through the paper. The light emitting unit in acquiring temperature information corresponding to the temperature of The above Light-emitting part Based on the temperature information corresponding to the temperature and the output of the light receiving unit, a moisture information determining step of determining moisture information of the paper; Based on the moisture information determined in the moisture information determination step, a process condition determination step of determining the process conditions; It is possible to execute the following. Effect of the Invention

[0036] According to the present invention, paper Water Minute information can be detected more accurately. [Brief description of the drawings]

[0037] [Figure 1] 1 is a diagram showing a schematic configuration of an image forming system according to an embodiment of the present invention; [Diagram 2] 1 is a block diagram showing a main functional configuration of an image forming system according to an embodiment of the present invention; [Diagram 3]FIG. 2 is a diagram illustrating an example of a schematic configuration of a first media sensor. [Figure 4A] FIG. 4 is a diagram showing an example of a position where a temperature detection sensor is arranged. [Figure 4B] FIG. 4 is a diagram showing an example of a position where a temperature detection sensor is arranged. [Figure 4C] FIG. 4 is a diagram showing an example of a position where a temperature detection sensor is arranged. [Figure 4D] FIG. 4 is a diagram showing an example of a position where a temperature detection sensor is arranged. [Diagram 5] 10 is a flowchart showing the flow of a process condition determination process executed by the image forming system. [Figure 6] 10 is a flowchart showing the flow of a moisture information determination process executed by the media detection device. [Figure 7] 13 is a diagram illustrating an example of a wavelength estimation value table of light emitted by a light-emitting unit. FIG. [Figure 8A] FIG. 13 is a diagram illustrating an example of a correction value table for plain paper. [Figure 8B] FIG. 13 is a diagram illustrating an example of a correction value table for thick paper. [Figure 9] FIG. 13 is a diagram illustrating an example of an individual difference correction value table. [Figure 10] 13 is a flowchart showing the flow of a process condition determination process executed by an image forming system according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] Hereinafter, an embodiment of the image forming system of the present invention will be described with reference to the drawings. Note that in the embodiment of the present invention, the image forming device provided in the image forming system will be described as a system color image forming device, but the present invention is not limited to this and can also be applied to, for example, a monochrome image forming device.

[0039] (1. Configuration of Image Forming System) Fig. 1 is a diagram showing a schematic configuration of an image forming system 100 according to this embodiment. Fig. 2 is a block diagram showing the main functional configuration of the image forming system 100.

[0040] The image forming system 100 according to this embodiment includes a paper feeder 10, a detection device 20 which is a media detection device, and an image forming device 30. In the image forming system 100, a paper feeder 10, a detector 20, and an image forming device 30 are arranged in this order from the upstream side along the paper transport direction.

[0041] (1-1. Configuration of the paper feeder) The paper feed device 10 includes a paper feed control unit 11, a transport unit 12, a paper feed unit 13, and the like. The paper feed control unit 11 is connected to the transport unit 12 and the paper feed unit 13 via a bus 14 .

[0042] The paper feed control unit 11 includes a central processing unit (CPU), a read only memory (ROM), and a random access memory (RAM). The CPU of the sheet feeding control unit 11 reads out a program stored in the ROM, loads it into the RAM, and generally controls each part of the sheet feeding device 10 according to the loaded program. For example, the paper feed control unit 11 conveys paper from one of the paper feed trays of the paper feed unit 13 to the detection device 20 in accordance with the job.

[0043] The transport unit 12 transports the paper through a transport path that connects the paper feed unit 13 to the detection device 20 . The paper feed unit 13 has paper feed trays that store paper according to predetermined paper types and sizes.

[0044] (1-2. Configuration of the detection device) The detector 20 is provided on the upstream side of the image forming apparatus 30 in the paper transport direction, and detects the paper transported from the paper feeder 10 . The detection device 20 includes a detection control unit 21, a transport unit 22, a first medium sensor 23, a second medium sensor 24, and a storage unit 25. The detection control unit 21 is connected to the transport unit 22, the first media sensor 23, the second media sensor 24, and the storage unit 25 via a bus .

[0045] The detection control unit 21 includes a CPU, a ROM, and a RAM. The CPU of the detection control unit 21 reads out a program stored in the ROM, loads it into the RAM, and generally controls each part of the detection device 20 according to the loaded program. For example, the detection control unit 21 causes the first media sensor 23 and the second media sensor 24 to detect the paper conveyed from the paper feeder 10. Then, the detection control unit 21 causes the conveying unit 22 to convey the detected paper to the image forming device 30.

[0046] The transport section 22 is made up of a plurality of roller pairs, and transports the paper transported from the paper feeder 10 to a first media sensor 23 and a second media sensor 24. Then, the conveying section 22 conveys the paper detected by the first medium sensor 23 and the second medium sensor 24 to the image forming device 30.

[0047] The first media sensor 23 is provided on the transport path upstream of an image forming section 38 (described later) of the image forming apparatus 30 in the paper transport direction. FIG. 3 is a schematic diagram showing the configuration of the first media sensor 23. As shown in FIG.

[0048] As shown in FIG. 3, the first media sensor 23 includes a first light-emitting unit 231, a second light-emitting unit 232, a light-receiving unit 233, a temperature detection sensor 234, lenses 235 and 236, and the like. The first light emitting unit 231 and the second light emitting unit 232 are light emitting units that irradiate light toward the paper.

[0049] The first light-emitting unit 231 emits first near-infrared light (reference light) in a specific wavelength band toward the paper P. A specific example of the first light-emitting unit 231 is an LED (Light Emitting Diode) or the like. The first near-infrared light is light whose absorptance in the paper P when reflected by the paper P does not depend on the moisture content of the paper P. The light receiving unit 233 receives, via the lens 236, the first near-infrared light that is emitted from the first light emitting unit 231 and reflected by the paper P via the lens 235. Then, the light receiving unit 233 outputs information on the first received light amount, which is the amount of the reflected first near-infrared light, to the detection control unit 21. Specific examples of the light receiving unit 233 include a CCD (Charge-Coupled Device) and a CMOS (Complementary Metal-Oxide-Semiconductor) image sensor.

[0050] The second light-emitting unit 232 emits second near-infrared light in a specific wavelength band toward the paper P. A specific example of the second light-emitting unit 232 is an LED or the like. The second near-infrared light is light whose absorptance in the paper P when reflected by the paper P varies depending on the moisture content of the paper P. The light receiving unit 233 receives, via the lens 236, the second near-infrared light that is emitted from the second light emitting unit 232 and reflected by the paper P via the lens 235. Then, the light receiving unit 233 outputs information on the second received light amount, which is the amount of the reflected second near-infrared light, to the detection control unit 21.

[0051] In other words, the first light emitting section 231 and the second light emitting section 232 emit light of wavelengths that are absorbed by the moisture in the paper at different rates. The second near-infrared light emitted by the second light-emitting unit 232 has a wavelength that is more absorbed by moisture in the paper than the first near-infrared light (reference light) emitted by the first light-emitting unit 231.

[0052] The detection control unit 21 determines the moisture content of the paper based on the ratio between the first amount of received light and the second amount of received light, which is the ratio between the outputs of the light receiving unit 233 for the first near-infrared light and the second near-infrared light. The higher the moisture content of the paper, the greater the absorption of the second near-infrared light, and therefore the smaller the second amount of received light. Therefore, based on a relational expression or table showing the relationship between the moisture content of the paper and the ratio between the first amount of received light and the second amount of received light, the ratio between the first amount of received light and the second amount of received light is made to correspond to the moisture content of the paper, and the moisture content of the paper can be calculated from the ratio between the first amount of received light and the second amount of received light.

[0053] The temperature detection sensor 234 detects the temperature of the second light-emitting part 232 and outputs the detection result to the detection control part 21. That is, the temperature information corresponding to the temperature of the media detection device includes temperature information corresponding to the temperature of the second light-emitting unit 232. Furthermore, the temperature information corresponding to the temperature of the media detection device includes temperature information corresponding to the temperature of the first media sensor 23 including the second light-emitting portion 232 .

[0054] Here, the position where the temperature detection sensor 234 is disposed will be described. 4A and 4B show an example of a position where the temperature detection sensor 234 is disposed. The first media sensor 23 further includes a support member 237 that supports the first light-emitting portion 231 and the second light-emitting portion 232, as shown in FIGS. 4A and 4B. The support member 237 is, for example, a substrate, and the thickness direction of the substrate is the Z-axis direction, the width direction is the X-axis direction, and the depth direction is the Y-axis direction. FIG. 4A is a diagram of the support member 237 as viewed from the positive side in the Z axis direction, and FIG. 4B is a diagram of the support member 237 as viewed from the negative side in the Y axis direction. In the supporting member 237, the surface on which the first light emitting portion 231 and the second light emitting portion 232 are provided is the positive side in the Z axis direction of the XY plane. 4A and 4B, the temperature sensor 234 is disposed near the second light-emitting unit 232. The temperature sensor 234 is provided on the positive side of the Z axis direction on the XY plane. In other words, the temperature sensor 234 is disposed in contact with the support member 237. 4A and 4B, the temperature detection sensor 234 is arranged in a non-contact state with the second light-emitting unit 232, but this is not limited thereto. The temperature detection sensor 234 may be arranged in contact with the second light-emitting unit 232. Arranging the temperature detection sensor in contact is preferable because it allows the temperature of the second light-emitting unit 232 to be detected more accurately.

[0055] 4C and 4D, the temperature detection sensor 234 may be disposed on the Z-axis direction positive side of the second light-emitting unit 232 and in a non-contact state with the support member 237. In other words, the temperature detection sensor 234 may be disposed facing the second light-emitting unit 232 and in a non-contact state. FIG. 4C is a diagram of the support member 237 viewed from the positive side in the Z axis direction, and FIG. 4D is a diagram of the support member 237 viewed from the negative side in the Y axis direction.

[0056] The second media sensor 24 is provided on the transport path upstream of the image forming unit 38 of the image forming apparatus 30 in the paper transport direction. The second media sensor 24 detects the basis weight of the paper on the transport path, and outputs the detection result to the detection control unit 21. In other words, the second media sensor 24 is a basis weight sensor. The basis weight of the paper is included in the physical properties corresponding to the paper type.

[0057] The storage unit 25 is configured with storage means such as a semiconductor memory such as a dynamic random access memory (DRAM) or a hard disk drive (HDD). The storage unit 25 stores a wavelength estimation value table used in the moisture information determination process described later. The storage unit 25 also stores a correction value table used in the moisture information determination process described below. In this embodiment, the storage unit 25 stores a correction value table for plain paper and a correction value table for thick paper. In this embodiment, plain paper is paper with a basis weight of 200 g / m 2 The following paper is considered to be cardboard with a basis weight of 200 g / m 2 It is a larger paper.

[0058] (1-3. Configuration of Image Forming Apparatus) The image forming apparatus 30 forms a color image by electrophotography based on image data obtained by reading an image from an original or image data of a job received from an external device (not shown). The image forming apparatus 30 includes a control unit 31, a storage unit 32, an operation unit 33, a display unit 34, an interface 35, a scanner 36, an image processing unit 37, an image forming unit 38, an image fixing unit 39, a conveying unit 40, and the like. The control unit 31 is connected to the memory unit 32, the operation unit 33, the display unit 34, the interface 35, the scanner 36, the image processing unit 37, the image forming unit 38, the image fixing unit 39, and the transport unit 40 via a bus 41.

[0059] The control unit 31 includes a CPU, a ROM, and a RAM. The CPU of the control unit 31 reads out a control program stored in the ROM, loads it into the RAM, and generally controls each unit of the image forming apparatus 30 according to the loaded program. For example, the control unit 31 causes the image processing unit 37 to perform a predetermined image processing on the image data and stores the image data in the storage unit 32. The control unit 31 also causes the conveying unit 40 to convey the paper, and causes the image forming unit 38 to form an image on the paper based on the image data stored in the storage unit 32.

[0060] The storage unit 32 is configured with storage means such as a semiconductor memory such as a DRAM or an HDD. The storage unit 32 stores image data acquired by the scanner 36, image data input from the outside via the interface 35, etc. The image data, etc. may be stored in a RAM included in the control unit 31.

[0061] The operation unit 33 includes input devices such as operation keys and a touch panel arranged over the screen of the display unit 34. The operation unit 33 converts input operations on these input devices into operation signals and outputs the operation signals to the control unit 31.

[0062] The display unit 34 includes a display device such as an LCD (Liquid Crystal Display), and displays an operation screen showing the state of the image forming system 100 and the contents of input operations to a touch panel.

[0063] The interface 35 is a means for transmitting and receiving data to and from an external computer, another image forming apparatus, etc. The interface 35 is configured, for example, by any one of various serial interfaces.

[0064] The scanner 36 reads an image formed on a sheet of paper, generates image data including monochromatic image data for each of the color components R (red), G (green), and B (blue), and stores the image data in the storage unit 32 .

[0065] The image processing unit 37 includes, for example, a rasterization processing unit, a color conversion unit, a gradation correction unit, and a halftone processing unit. The image processing unit 37 performs various image processes on the image data stored in the storage unit 32 and stores the processed image data in the storage unit 32.

[0066] The image forming unit 38 forms an image on a sheet based on the image data stored in the storage unit 32. The image forming unit 38 includes four sets of exposure units 381, photoconductor drums 382, ​​and development units 383, each set corresponding to the color components of C (cyan), M (magenta), Y (yellow), and K (black). The image forming unit 38 also includes a transfer body 384 and a secondary transfer roller 385.

[0067] The exposure unit 381 includes an LD (Laser Diode) as a light-emitting element. The exposure unit 381 drives the LD based on image data, irradiates and exposes the charged photoconductor drum 382 with laser light, and forms an electrostatic latent image on the photoconductor drum 382. The development unit 383 supplies toner (color material) of a predetermined color (any of C, M, Y, and K) onto the exposed photoconductor drum 382 by a charged development roller, and develops the electrostatic latent image formed on the photoconductor drum 382.

[0068] Images (monochrome images) formed with C, M, Y and K toners on four photoconductor drums 382 corresponding to C, M, Y and K, respectively, are sequentially superimposed and transferred from each photoconductor drum 382 onto a transfer body 384. As a result, a color image having C, M, Y and K as color components is formed on the transfer body 384. The transfer body 384 is an endless belt wound around a plurality of transfer body transport rollers, and rotates in accordance with the rotation of each transfer body transport roller.

[0069] Secondary transfer roller 385 transfers the color image on transfer body 384 onto paper fed from paper feeder 10. More specifically, the paper and transfer body 384 are sandwiched in a transfer nip formed by pressure contact between a pair of secondary transfer rollers 385. Then, a predetermined transfer voltage is applied to secondary transfer roller 385, so that toner forming the color image on transfer body 384 is attracted to the paper and transferred to the paper.

[0070] The image fixing unit 39 includes a fixing roller, a pressure roller, and the like, and performs a fixing process of applying heat and pressure to the paper onto which the toner has been transferred, thereby fixing the toner to the paper.

[0071] The transport section 40 includes a plurality of paper transport rollers that rotate while clamping the paper to transport the paper, and transports the paper along a predetermined transport path. The transport section 40 includes an inversion mechanism 401 that inverts the paper that has been subjected to the fixing process by the image fixing section 39 and transports the paper to the secondary transfer roller 385. In the image forming device 30, when images are formed on both sides of the paper, the inversion mechanism 401 inverts the paper and the paper is discharged after images are formed on both sides. When an image is formed only on one side of the paper, the inversion mechanism 401 does not invert the paper and the paper with the image formed on one side is discharged.

[0072] In the present embodiment, the control unit 31 of the image forming apparatus 30 controls the entire image forming system 100 in an integrated manner, but this is not limited thereto. The detection control unit 21 of the detection apparatus 20 may be configured to control the entire image forming system 100 in an integrated manner.

[0073] (2. Operation of the Image Forming System) Next, the operation of the image forming system 100 will be described. FIG. 5 is a flowchart showing the flow of a process condition determination process that is executed when the image forming apparatus 30 receives image data and setting information of a print job via the interface 35. The process condition determination process of FIG. 5 is executed by the CPU of the control unit 31 of the image forming apparatus 30 in cooperation with a process condition control program stored in the ROM.

[0074] The control unit 31 executes a process condition determination process to determine process conditions for image formation by the image forming unit 38, based on moisture information corresponding to the moisture amount or moisture percentage of the paper. Here, the control unit 31 functions as a process condition control unit. The process conditions are, for example, transfer conditions when a color image on the transfer body 384 is transferred to paper. Specifically, the transfer conditions are a transfer voltage value and a transfer current value applied to the secondary transfer roller 385 when the color image on the transfer body 384 is transferred to paper.

[0075] The control unit 31 may determine process conditions other than the transfer conditions by executing a process condition determination process. Furthermore, the control unit 31 may determine transfer conditions other than the transfer voltage value and the transfer current value applied to the secondary transfer roller 385 by executing a process condition determination process.

[0076] (2-1. Process condition determination processing) In the process condition determination process, first, the control unit 31 causes the sheet feeding device 10 to feed a sheet (job target sheet) on which an image is to be formed in a print job from the sheet feeding unit 13, and conveys the sheet to the detection device 20 (step S1).

[0077] Next, the control unit 31 causes the detection device 20 to execute a moisture information determination process for the paper that is the object of the job, and obtains moisture information corresponding to the moisture amount or moisture percentage of the paper from the detection device 20 (step S2). FIG. 6 shows a flowchart of the moisture information determination process. The moisture information determination process in FIG. 6 is executed by the CPU of the detection control unit 21 in cooperation with a media detection program stored in the ROM.

[0078] The detection control unit 21 executes a moisture information determination process to determine moisture information corresponding to the moisture amount or moisture percentage of the paper based on temperature information (detection result of the temperature detection sensor 234) corresponding to the temperature of the media detection device and the output of the light receiving unit 233. Here, the detection control unit 21 functions as a moisture information control unit.

[0079] (2-2. Moisture information determination process) First, the detection control unit 21 detects the basis weight of the paper on the transport path by the second media sensor 24, and obtains the detection result (step A1). Next, the detection control unit 21 determines the paper type of the paper based on the basis weight of the paper acquired in step A1 (step A2). That is, the detection control unit 21 determines the paper type of the paper based on the detection result of the second media sensor 24. Here, the detection control unit 21 functions as a paper type determination unit. For example, if the paper weight is 200 g / m 2 If the basis weight of the paper is less than 200 g / m, the detection control unit 21 determines that the paper is plain paper. 2 If it is greater, the detection control unit 21 determines that the paper is cardboard.

[0080] Next, the detection control unit 21 acquires information on the first amount of received light and the second amount of received light as the output of the light receiving unit 233 from the first media sensor 23 (step A3). Next, the detection control unit 21 calculates and determines a provisional moisture content of the paper from the ratio between the first amount of received light and the second amount of received light based on the output of the light receiving unit 233 acquired in step A2 (step A4).

[0081] Next, the detection control unit 21 acquires the temperature of the second light-emitting unit 232 from the temperature detection sensor 234 (step A5). This step A5 is an acquisition step. Next, the detection control unit 21 acquires the wavelength estimates of the first near-infrared light and the second near-infrared light from the wavelength estimate table based on the temperature of the second light-emitting unit 232 acquired in step A5 (step A6).

[0082] FIG. 7 is a diagram showing an example of a wavelength estimation value table stored in the storage unit 25. As shown in FIG. The inventors have actually investigated the phenomenon in which measurement results change for paper in the same state when a moisture sensor is installed in an image forming apparatus as a media sensor, and have discovered the following phenomenon. Specifically, the inventors discovered that moisture sensitivity changes as the wavelength of light emitted by the light-emitting section (such as an LED) of the moisture sensor changes due to a rise in temperature caused by self-heating. They have found that this phenomenon causes a problem in which the moisture content of paper detected by the media sensor is in error compared to the actual moisture content of the paper. The above wavelength estimation value table indicates the relationship between the detection result (detected temperature) by the temperature detection sensor 234, the wavelength estimation value of the first near-infrared light emitted by the first light-emitting unit 231, and the wavelength estimation value of the second near-infrared light emitted by the second light-emitting unit 232. In addition, instead of using the wavelength estimation value table, the detection control unit 21 may obtain the wavelength estimation values ​​of the first near-infrared light and the second near-infrared light from a relational equation showing the relationship between the temperature detected by the temperature detection sensor 234, the wavelength estimation value of the first near-infrared light, and the wavelength estimation value of the second near-infrared light.

[0083] Next, the detection control unit 21 obtains a correction value for correcting the provisional moisture content of the paper from the correction value table based on the paper type determined in step A2 and the wavelength estimates of the first near-infrared light and the second near-infrared light obtained in step A6 (step A7). That is, when the detection control unit 21 determines in step A2 that the paper type is plain paper, it acquires the correction value from the correction value table for plain paper. Also, when the detection control unit 21 determines in step A2 that the paper type is thick paper, it acquires the correction value from the correction value table for thick paper.

[0084] Fig. 8A shows an example of a correction value table for plain paper, and Fig. 8B shows an example of a correction value table for thick paper. 8A and 8B, the reference wavelengths are set to a case where the estimated wavelength value of the first near-infrared light is 1450 nm and the estimated wavelength value of the second near-infrared light is 1300 nm. Therefore, the correction value in this case is 0. Note that, as shown in FIG. 7, this case is a case where the detected temperature of the temperature detection sensor 234 is 20° C. The wavelength estimates of the first near-infrared light and the second near-infrared light, which are used as the reference wavelengths, are not limited to the examples shown in FIGS. 8A and 8B, and may be other wavelength estimates.

[0085] In the example shown in FIG. 8A, if the estimated wavelength value of the first near-infrared light is 1400 nm, the estimated wavelength value of the second near-infrared light is 1250 nm, and the provisional moisture content of the paper is, for example, 5%, the correction value is +5%. Furthermore, if the estimated wavelength value of the first near-infrared light is 1500 nm, the estimated wavelength value of the second near-infrared light is 1400 nm, and the provisional moisture content of the paper is, for example, 20%, the correction value is −10%.

[0086] In the example shown in FIG. 8B, if the estimated wavelength value of the first near-infrared light is 1400 nm, the estimated wavelength value of the second near-infrared light is 1250 nm, and the provisional moisture content of the paper is, for example, 5%, the correction value is +5%. Furthermore, if the estimated wavelength value of the first near-infrared light is 1500 nm, the estimated wavelength value of the second near-infrared light is 1400 nm, and the provisional moisture content of the paper is, for example, 20%, the correction value is −5%.

[0087] 8A and 8B, when the temperature detected by the temperature detection sensor 234 is lower than 20° C. (reference temperature), the correction value is a value that corrects the provisional moisture percentage to be higher. When the temperature detected by the temperature detection sensor 234 is higher than 20° C. (reference temperature), the correction value is a value that corrects the provisional moisture percentage to be lower.

[0088] In addition, instead of using the correction value table, the detection control unit 21 may obtain the correction value from a relational equation that shows the relationship between the wavelength estimate value of the first near-infrared light, the wavelength estimate value of the second near-infrared light, the tentative moisture content of the paper, and the correction value.

[0089] Next, the detection control unit 21 corrects the provisional moisture content of the paper determined in step A4 with the correction value acquired in step A7 to determine the moisture content of the paper (step A8), and ends this process. Step A8 is a moisture information determination step.

[0090] The detection control unit 21 executes the moisture information determination process to determine provisional moisture information (moisture percentage) based on the output of the light receiving unit 233. Then, the detection control unit 21 acquires an estimate of the wavelength of the light emitted by the light emitting unit based on the temperature of the light emitting unit (the temperature detected by the temperature detection sensor 234). Then, the detection control unit 21 determines the moisture information by correcting the provisional moisture information based on the acquired estimate of the wavelength.

[0091] Furthermore, the detection control unit 21 executes the moisture information determination process to determine the moisture information (moisture percentage) of the paper while the paper is being transported. The detection control unit 21 may determine the moisture information of the paper for each sheet that is conveyed, or may determine the moisture information (moisture percentage) of the paper multiple times for one sheet that is conveyed. That is, the detection control unit 21 determines the moisture information (moisture percentage) of the paper in accordance with the temperature detected by the temperature detection sensor 234 during the transport of the paper.

[0092] In the moisture information determination process, the detection control unit 21 may correct individual differences in the wavelengths of light emitted by the first light-emitting unit 231 and the second light-emitting unit 232 due to individual differences (eg, individual differences in LEDs). In this case, the storage unit 25 stores an individual difference correction value table for correcting the individual differences of the first light-emitting unit 231 and the second light-emitting unit 232. FIG. 9 shows an example of the individual difference correction value table.

[0093] 9, the reference wavelength is set to a value of 1450 nm for the wavelength of the first near-infrared light and a value of 1300 nm for the wavelength of the second near-infrared light. Therefore, the correction value in this case is 0. The pre-measured values ​​of the wavelength of the first near-infrared light and the wavelength of the second near-infrared light that are used as the reference wavelength are not limited to the example shown in FIG. 9, and may be other pre-measured values.

[0094] In the example shown in FIG. 9, if the preliminary measured value of the wavelength of the first near-infrared light is 1400 nm, the preliminary measured value of the wavelength of the second near-infrared light is 1250 nm, and the provisional moisture content of the paper is, for example, 5%, the correction value is +5%. Furthermore, if the preliminary measured value of the wavelength of the first near-infrared light is 1500 nm, the preliminary measured value of the wavelength of the second near-infrared light is 1400 nm, and the provisional moisture content of the paper is, for example, 20%, the correction value is −10%.

[0095] Returning to FIG. 5, the control unit 31 determines process conditions for image formation by the image forming unit 38 based on the moisture information of the paper determined in step S2 (step S3), and ends this process.

[0096] (Modification) Next, a modified example of the present invention will be described. In the modified example, the same components as those in the above embodiment are denoted by the same reference numerals, and the description thereof will be omitted. FIG. 10 is a flowchart showing the flow of the process condition determination process of this modified example.

[0097] In the process condition determination process of this modified example, the control unit 31 performs step S1a similar to the process condition determination process step S1 of the above embodiment. Next, the control unit 31 acquires information on the first amount of received light and the second amount of received light as the output of the light receiving unit 233 of the first media sensor 23 from the detection device 20 (step S2a). Next, the control unit 31 acquires the temperature of the second light-emitting unit 232 from the detection device 20 as the detection result of the temperature detection sensor 234 (step S3a). This step S3a is an acquisition step.

[0098] Next, the control unit 31 determines process conditions for image formation by the image forming unit 38 based on the output of the light receiving unit 233 acquired in step S2a and the temperature of the second light emitting unit 232 acquired in step S3a (step S4a), and ends this process. Step S4a is a process condition determination step. In other words, in this modified example, the control unit 31 determines the process conditions directly from the output of the light receiving unit 233 and the temperature of the second light emitting unit 232, without the detection control unit 21 determining moisture information corresponding to the moisture content or moisture percentage of the paper.

[0099] The present invention has been described above based on the above embodiment, but the description of the above embodiment is merely one example of the image forming system according to the present invention, and the present invention is not limited to this. For example, in the above embodiment, the detection control unit 21 determines the moisture percentage of the paper in the moisture information determination process, but this is not limited to the above. The detection control unit 21 may determine the moisture amount of the paper. Furthermore, the detection control unit 21 may determine an index indicating the moisture content or moisture percentage of the paper in the moisture information determination process. The index indicating the moisture content or moisture percentage of the paper is, for example, a voltage value or a current value output by the light receiving unit 233. In other words, the moisture information corresponding to the moisture amount or moisture percentage of the paper includes the moisture amount of the paper, the moisture percentage of the paper, and an index indicating the moisture amount or moisture percentage of the paper.

[0100] Furthermore, the detection control unit 21 may determine moisture information corresponding to the moisture amount or moisture percentage of the paper based on the estimated values ​​of the temperatures of the first light-emitting unit 231 and the second light-emitting unit 232 and the output of the light-receiving unit 233. For example, the detection control unit 21 calculates an estimated value of the temperature of the first light-emitting unit 231 and the second light-emitting unit 232 based on the operation time of the first light-emitting unit 231 and the second light-emitting unit 232 . That is, the temperature information corresponding to the temperature of the media sensing device includes an estimate of the temperature of the media sensing device based on the operation time of the first light-emitting unit 231 and the second light-emitting unit 232.

[0101] In addition, if the image forming device 30 is equipped with a detection unit that detects the temperature inside the image forming device 30, the detection control unit 21 may determine moisture information corresponding to the moisture content or moisture percentage of the paper based on the detection result of the detection unit and the output of the light receiving unit 233. That is, the temperature information corresponding to the temperature of the media sensing device includes information on the temperature inside the image forming device 30 .

[0102] In the above embodiment, the light receiving unit 233 receives the light emitted from the first light emitting unit 231 and the second light emitting unit 232 and reflected by the paper P, but this is not limited to the above. The light receiving unit 233 may be configured to receive the light emitted from the first light emitting unit 231 and the second light emitting unit 232 and transmitted through the paper P.

[0103] [3. Effects] As described above, the media detection device (detection device 20) of this embodiment is a media detection device for detecting moisture information corresponding to the moisture content or moisture percentage of paper, and includes an emitter (first emitter 231 and second emitter 232) that emits light, a light receiver 233 that receives light that is reflected by the paper or transmitted through the paper, and a moisture information control unit (detection control unit 21) that determines moisture information based on temperature information corresponding to the temperature of the media detection device and the output of the light receiver 233. This makes it possible to determine moisture information corresponding to the moisture content or moisture percentage of the paper in accordance with temperature information corresponding to the temperature of the media detection device, thereby making it possible to more accurately detect the moisture information corresponding to the moisture content or moisture percentage of the paper.

[0104] Furthermore, in the media detection device (detection device 20) of this embodiment, the moisture information control unit (detection control unit 21) determines moisture information based on temperature information corresponding to the temperature of the light-emitting unit (first light-emitting unit 231 and second light-emitting unit 232) and the output of the light-receiving unit 233. This makes it possible to determine moisture information corresponding to the moisture amount or moisture percentage of the paper according to temperature information corresponding to the temperature of the light emitting section.

[0105] In the media detection device (detection device 20) of this embodiment, the light emitting section includes a first light emitting section 231 and a second light emitting section 232 for emitting light of wavelengths with different absorbances by moisture. Moreover, in the media detection device (detection device 20) of this embodiment, the first light-emitting unit 231 emits reference light, the second light-emitting unit 232 emits light of a wavelength that is absorbed by moisture more efficiently than the reference light, and the moisture information control unit (detection control unit 21) determines moisture information based on temperature information corresponding to the temperature of the media detection device and the output of the light-receiving unit 233 in response to the reference light and the light emitted by the second light-emitting unit 232. Furthermore, in the media detection device (detection device 20) of this embodiment, the moisture information control unit (detection control unit 21) determines moisture information based on temperature information corresponding to the temperature of the media detection device and the ratio of the output of the light receiving unit 233 to the reference light and the light emitted by the second light emitting unit 232. In the media detection device (detection device 20) of this embodiment, the moisture information control unit (detection control unit 21) determines the moisture information based on the output of the light receiving unit 233 and temperature information corresponding to the temperature of the second light emitting unit 232. This makes it possible to determine moisture information corresponding to the moisture amount or moisture percentage of the paper according to temperature information corresponding to the temperature of the second light-emitting element 232.

[0106] Furthermore, the media detection device (detection device 20) of this embodiment is equipped with a temperature detection sensor 234 that detects the temperature of the media detection device, and the temperature information corresponding to the temperature of the media detection device is temperature information corresponding to the detection result of the temperature detection sensor 234. This allows the temperature detection sensor 234 to easily obtain temperature information corresponding to the temperature of the media detection device.

[0107] Furthermore, in the media detection device (detection device 20) of this embodiment, the moisture information control section (detection control section 21) determines the moisture information while the paper is being transported. This makes it possible to more accurately detect moisture information corresponding to the amount of moisture or moisture percentage of the paper being transported.

[0108] Furthermore, in the media detection device (detection device 20) of this embodiment, the moisture information control section (detection control section 21) determines moisture information for each sheet of paper. This makes it possible to more accurately detect moisture information corresponding to the moisture amount or moisture percentage of each sheet of paper.

[0109] Furthermore, in the media detection device (detection device 20) of this embodiment, the moisture information control section (detection control section 21) determines the moisture information for one sheet of paper multiple times. This makes it possible to detect moisture information corresponding to the moisture content or moisture percentage of a sheet of paper with greater accuracy.

[0110] Furthermore, in the media detection device (detection device 20) of this embodiment, the moisture information control unit (detection control unit 21) determines moisture information based on temperature information corresponding to the temperature of the media detection device detected during paper transport and the output of the light receiving unit 233. This makes it possible to determine moisture information corresponding to the moisture content or moisture percentage of the paper in accordance with temperature information corresponding to the temperature of the media detection device during paper transport.

[0111] Furthermore, in the media detection device (detection device 20) of this embodiment, the light-emitting unit (first light-emitting unit 231 and second light-emitting unit 232) and the light-receiving unit 233 are included in the first media sensor 23, and the temperature information corresponding to the temperature of the media detection device is temperature information corresponding to the temperature of the first media sensor. This makes it possible to determine moisture information corresponding to the moisture amount or moisture percentage of the paper according to temperature information corresponding to the temperature of the first media sensor 23.

[0112] In the media detection device (detection device 20) of this embodiment, the first media sensor 23 is disposed on the transport path of the paper. This makes it possible to detect moisture information corresponding to the moisture amount or moisture percentage of the paper on the transport path.

[0113] In the medium detection device (detection device 20) of this embodiment, the first medium sensor 23 is disposed on a paper transport path for transporting the paper to an image forming unit 38 capable of forming an image on the paper. This makes it possible to detect moisture information corresponding to the moisture amount or moisture percentage of the paper before image formation.

[0114] Furthermore, in the media detection device (detection device 20) of this embodiment, the moisture information control unit (detection control unit 21) determines provisional moisture information based on the output of the light receiving unit 233, and determines the moisture information by correcting the provisional moisture information based on temperature information corresponding to the temperature of the media detection device. This makes it possible to determine moisture information corresponding to the moisture amount or moisture percentage of the paper according to temperature information corresponding to the temperature of the media detection device.

[0115] Furthermore, in the media detection device (detection device 20) of this embodiment, the moisture information control unit (detection control unit 21) acquires information on the wavelength of light emitted by the light-emitting units (first light-emitting unit 231 and second light-emitting unit 232) based on the temperature of the light-emitting units, and corrects the provisional moisture information based on the acquired wavelength information. This makes it possible to determine moisture information corresponding to the moisture amount or moisture percentage of the paper according to temperature information corresponding to the temperature of the light emitting section.

[0116] In addition, the media detection device (detection device 20) of this embodiment is equipped with a temperature detection sensor 234 that detects the temperature of the media detection device, and the moisture information control unit (detection control unit 21) corrects the provisional moisture information to be lower when the temperature detected by the temperature detection sensor 234 is higher than the reference temperature, and corrects the provisional moisture information to be higher when the detected temperature is lower than the reference temperature. This makes it possible to determine moisture information corresponding to the moisture amount or moisture percentage of the paper according to temperature information corresponding to the temperature of the media detection device.

[0117] In the media detection device (detection device 20) of this embodiment, the light emitting units (first light emitting unit 231 and second light emitting unit 232) include LEDs (Light Emitting Diodes). Therefore, even if the light emitting section generates heat and the wavelength of the light emitted by the light emitting section changes, the moisture information corresponding to the moisture amount or moisture percentage of the paper can be detected with high accuracy.

[0118] In the medium detection device (detection device 20) of this embodiment, the temperature detection sensor 234 is disposed in contact with a member (support member 237) that supports the light emitting parts (first light emitting part 231 and second light emitting part 232). This allows the temperature of the light-emitting portion to be detected with high accuracy.

[0119] In the medium detection device (detection device 20) of this embodiment, the temperature detection sensor 234 is disposed opposite and in a non-contact manner to the light-emitting parts (first light-emitting part 231 and second light-emitting part 232). This allows the temperature of the light-emitting portion to be detected with high accuracy.

[0120] Furthermore, in the media detection device (detection device 20) of this embodiment, the moisture information control unit (detection control unit 21) determines the moisture information based on the paper type of the paper. This makes it possible to determine moisture information corresponding to the moisture content or moisture percentage of the paper depending on the paper type.

[0121] In addition, the media detection device (detection device 20) of this embodiment is equipped with a second media sensor 24 for detecting physical properties corresponding to the paper type, and a paper type determination unit (detection control unit 21) that determines the paper type based on the detection results of the second media sensor 24. In the media detection device (detection device 20) of this embodiment, the second media sensor 24 is a basis weight sensor. Therefore, the type of paper can be easily determined by detecting the basis weight of the paper.

[0122] In addition, the image forming system 100 of this embodiment is an image forming system that includes a media detection device (detection device 20) and an image forming unit 38 capable of forming an image on paper, and includes a process condition control unit (control unit 31) that determines process conditions for image formation in the image forming unit 38 based on the moisture information determined by the moisture information control unit (detection control unit 21). This makes it possible to determine process conditions according to moisture information corresponding to the moisture amount or moisture percentage of the paper detected with higher accuracy.

[0123] In the image forming system 100 of the present embodiment, the process conditions include transfer conditions. This makes it possible to determine transfer conditions according to moisture information corresponding to the moisture amount or moisture percentage of the paper that has been detected with higher accuracy.

[0124] In the image forming system 100 of this embodiment, the transfer conditions include a transfer current and a transfer voltage. This makes it possible to determine the transfer current and transfer voltage in accordance with moisture information corresponding to the moisture content or moisture percentage of the paper that has been detected with higher accuracy.

[0125] In addition, the image forming system 100 of this embodiment includes an image forming unit 38 that forms an image on paper, a media detection device (detection device 20) for detecting moisture information corresponding to the moisture content or moisture percentage of the paper, and a process condition control unit (control unit 31) that determines process conditions in the image forming unit 38. The media detection device has an light emitting unit (first light emitting unit 231 and second light emitting unit 232) that emits light, and a light receiving unit 233 that receives light that is reflected by or transmitted through the paper, and the process condition control unit determines the process conditions based on temperature information corresponding to the temperature of the media detection device and the output of the light receiving unit 233. This makes it possible to determine process conditions according to moisture information corresponding to the moisture content or moisture percentage of the paper according to temperature information corresponding to the temperature of the media detection device.

[0126] In addition, the media detection program of this embodiment is a media detection program for detecting moisture information corresponding to the moisture content or moisture percentage of paper, and is capable of causing a computer (detection control unit 21) to execute an acquisition step of acquiring temperature information corresponding to the temperature of a media detection device (detection device 20) having an light-emitting unit (first light-emitting unit 231 and second light-emitting unit 232) that emits light and a light-receiving unit 233 that receives light that is reflected by or transmitted through the paper, and a moisture information determination step of determining moisture information based on the temperature information corresponding to the temperature of the media detection device and the output of the light-receiving unit 233. This makes it possible to determine moisture information corresponding to the moisture amount or moisture percentage of the paper according to temperature information corresponding to the temperature of the media detection device.

[0127] In addition, the process condition program of this embodiment is a process condition control program for determining process conditions for forming an image on paper in the image forming unit 38, and is capable of causing a computer (control unit 31) to execute an acquisition step of acquiring temperature information corresponding to the temperature of a media detection device (detection device 20) having an light-emitting unit (first light-emitting unit 231 and second light-emitting unit 232) that irradiates light and a light-receiving unit 233 that receives light that is reflected by or transmitted through the paper, and a process condition determination step of determining process conditions based on the temperature information corresponding to the temperature of the media detection device and the output of the light-receiving unit 233. This makes it possible to determine process conditions according to moisture information corresponding to the moisture content or moisture percentage of the paper according to temperature information corresponding to the temperature of the media detection device.

[0128] The above-described embodiments are merely examples of the media detection device, image forming system, media detection program, and process condition control program according to the present invention, and are not intended to limit the scope of the present invention. The detailed configurations and operations of the components constituting the device may be modified as appropriate without departing from the spirit of the present invention.

[0129] For example, in the above embodiment, the detection control unit 21 is described as a moisture information control unit, but this is not limited to the above. The control unit 31 of the image forming apparatus 30 may function as a moisture information control unit. In this case, the control unit 31 acquires temperature information corresponding to the temperature of the media detection device from the detection device 20 and the output of the light receiving unit 233, and determines moisture information corresponding to the moisture amount or moisture percentage of the paper.

[0130] In the above embodiment, the first media sensor 23 is provided on the transport path upstream of the image forming unit 38 in the paper transport direction and outputs the first and second amounts of received light for the paper before image formation, but this is not limited to the above. The first media sensor 23 may be provided on the transport path downstream of the image forming unit 38 in the paper transport direction and outputs the first and second amounts of received light for the paper after image formation. The first media sensor 23 may be provided on the transport path both upstream and downstream of the image forming unit 38 in the paper transport direction.

[0131] In addition, in the above embodiment, the media detection device is illustrated as being applied to an image forming apparatus 30 using an electrophotographic printing method, but this is not limited to this and the device can also be applied to an inkjet image forming apparatus or an image forming apparatus using other printing methods. [Explanation of symbols]

[0132] 100 Image forming system 10 Paper feeder 11 Paper feed control unit 12 Conveyor section 13 Paper feed section 14 Bus 20 Detection device (media detection device) 21 Detection control unit (moisture information control unit, paper type determination unit) 22 Conveyor section 23 1st Media Sensor 231 First light-emitting part (light-emitting part) 232 Second light-emitting part (light-emitting part) 233 Light receiving section 234 Temperature Sensor 235, 236 Lenses 237 Supporting member 24 2nd Media Sensor 25 Memory section 26 Bus 30 Image forming device 31 Control section (process condition control section) 32 Storage section 33 Operation section 34 Display section 35 Interface 36 Scanner 37 Image Processing Section 38 Image forming section 381 Exposure Section 382 Photoconductor drum 383 Development Department 384 Transcript 385 Secondary transfer roller 39 Image fixing section 40 Conveyor 401 Reversal mechanism 41 Bus P paper

Claims

1. A media detection device for detecting moisture information of a paper sheet, comprising: A light emitting unit that emits light; a light receiving section that receives the light reflected by the paper or transmitted through the paper; a moisture information control unit that determines the moisture information based on temperature information corresponding to the temperature of the light-emitting unit and an output of the light-receiving unit; A media sensing device comprising:

2. The media detection device according to claim 1 , wherein the light emitting section includes a first light emitting section and a second light emitting section for emitting light of wavelengths having different moisture absorption rates.

3. The first light emitting unit emits a reference light, the second light-emitting unit emits light of a wavelength having a higher absorption rate by moisture than the reference light, The media detection device according to claim 2 , wherein the moisture information control unit determines the moisture information based on the temperature information and an output of the light receiving unit in response to the reference light and the light emitted by the second light emitting unit.

4. The media detection device according to claim 3 , wherein the moisture information control unit determines the moisture information based on the temperature information and a ratio of an output of the light receiving unit to the reference light and the light emitted by the second light emitting unit.

5. The media detection device according to claim 3 , wherein the moisture information control unit determines the moisture information based on temperature information corresponding to a temperature of the second light-emitting unit and an output from the light-receiving unit.

6. A temperature detection sensor is provided to detect the temperature of the light-emitting unit, The medium detection device according to claim 1 , wherein the temperature information corresponding to the temperature of the light-emitting portion is temperature information corresponding to a detection result of the temperature detection sensor.

7. The media sensing device of claim 1 , wherein the moisture information control unit determines the moisture information while the paper is being transported.

8. The media detection device according to claim 7 , wherein the moisture information control unit determines the moisture information for each of the sheets of paper.

9. The media detection device according to claim 7 , wherein the moisture information control unit determines the moisture information a plurality of times for one sheet of paper.

10. The media detection device according to claim 7 , wherein the moisture information control unit determines the moisture information based on the temperature information detected during paper transport and an output from the light receiving unit.

11. The media detection device according to claim 1 , wherein the light emitting section and the light receiving section are included in a first media sensor.

12. The media detection device according to claim 11 , wherein the first media sensor is disposed on a transport path of the paper.

13. The media detection device according to claim 12 , wherein the first media sensor is disposed on a transport path for transporting the paper to an image forming unit capable of forming an image on the paper.

14. The media detection device according to claim 1 , wherein the moisture information control unit determines provisional moisture information based on the output of the light receiving unit, and determines the moisture information by correcting the provisional moisture information based on temperature information corresponding to the temperature of the light emitting unit.

15. The media detection device according to claim 14 , wherein the moisture information control unit obtains information on a wavelength of light emitted by the light emitting unit based on a temperature of the light emitting unit, and corrects the provisional moisture information based on the obtained wavelength information.

16. A temperature detection sensor is provided to detect the temperature of the light-emitting unit, The media detection device of claim 14, wherein the moisture information control unit corrects the provisional moisture information to be lower when the detected temperature by the temperature detection sensor is higher than a reference temperature, and corrects the provisional moisture information to be higher when the detected temperature is lower than the reference temperature.

17. The media detection device according to claim 1 , wherein the light emitting unit includes an LED (Light Emittng Diode).

18. The medium detection device according to claim 6 , wherein the temperature detection sensor is disposed in contact with a member supporting the light emitting portion.

19. The medium detection device according to claim 6 , wherein the temperature detection sensor is disposed opposite to and in non-contact with the light emitting unit.

20. The media detection device according to claim 1 , wherein the moisture information control unit determines the moisture information based on the temperature information, an output from the light receiving unit, and a paper type of the paper.

21. a second media sensor for detecting a physical property corresponding to the paper type; a paper type determination unit that determines the paper type based on a detection result of the second media sensor; 21. The media sensing device of claim 20, comprising:

22. The media sensing device of claim 21 , wherein the second media sensor is a basis weight sensor.

23. The media sensing device of any one of claims 1 to 22; an image forming unit capable of forming an image on the paper; An image forming system comprising: an image forming system including a process condition control unit that determines process conditions for image formation in the image forming unit based on the moisture information determined by the moisture information control unit;

24. 24. The imaging system of claim 23, wherein the process conditions include transfer conditions.

25. 25. The imaging system of claim 24, wherein the transfer conditions include a transfer current and a transfer voltage.

26. an image forming unit that forms an image on a sheet; a media detection device for detecting moisture information of the paper; a process condition control unit that determines process conditions in the image forming unit; Equipped with the media detection device includes a light emitting unit that irradiates light, a light receiving unit that receives the light that is reflected by the paper or transmitted through the paper, and a moisture information control unit that determines the moisture information based on temperature information corresponding to a temperature of the light emitting unit and an output of the light receiving unit; The process condition control unit determines the process conditions based on the moisture information determined by the moisture information control unit.

27. A media detection program for detecting moisture information of paper, On the computer, an acquisition step of acquiring temperature information corresponding to a temperature of a light-emitting unit in a media detection device having a light-emitting unit that irradiates light and a light-receiving unit that receives the light reflected by the paper or transmitted through the paper; a moisture information determination step of determining the moisture information based on temperature information corresponding to the temperature of the light-emitting unit and an output of the light-receiving unit; A media detection program that can

28. A process condition control program for determining process conditions for forming an image on a sheet in an image forming unit, On the computer, an acquisition step of acquiring temperature information corresponding to a temperature of a light-emitting unit in a media detection device having a light-emitting unit that irradiates light and a light-receiving unit that receives the light reflected by the paper or transmitted through the paper; a moisture information determination step of determining moisture information of the paper based on temperature information corresponding to the temperature of the light-emitting unit and an output of the light-receiving unit; a process condition determination step of determining the process conditions based on the moisture information determined in the moisture information determination step; A process condition control program capable of executing the above.

Images