Image forming apparatus

Abstract

The invention provides an image forming apparatus capable of improving the precision of the measured density of a toner image for adjustment and forming an image at a suitable density. The image forming apparatus includes a belt unit, a photosensitive drum, a sensor, and a controller. The belt unit includes an endless belt and a belt memory that stores belt information including at least one of vendor information of the belt, category information of the belt, and use history information of the belt. The sensor has a light-emitting element that emits light toward the tape and a light-receiving element that can receive light reflected by the tape. The control unit is capable of executing a correction process for correcting the value of the measured intensity of the reflected light from the surface of the tape without the toner image, said value being detected by the sensor. When the control unit executes the correction process, the value of the measured intensity of the reflected light is corrected on the basis of the tape information stored in the tape memory (S14).

Description

Technical Field

[0001] The present invention relates to an image forming apparatus including a belt unit. Background Art

[0002] Conventionally, an image forming apparatus having a belt unit is known (see Patent Document 1). In the image forming apparatus, a sensor for measuring the density of an adjustment toner image formed on the belt is arranged. The sensor has two light receiving elements for receiving regular reflection and diffuse reflection of light irradiated from a light emitting element, and calculates the density of the adjustment toner image based on the detection values ​​of the light received from the two light receiving elements.

[0003] Patent Literature

[0004] Patent Document 1: Japanese Patent Application Publication No. 2013-195066

[0005] Technical problem to be solved by the invention

[0006] The belt used in the belt unit may be of different manufacturers and types. However, in the conventional image forming apparatus, even when the belt is replaced, the density of the adjustment toner image is calculated regardless of the manufacturer and type of the belt, so the detection accuracy of the density of the adjustment toner image may be low. As a result, an image may not be formed at an appropriate density. Summary of the invention

[0007] Therefore, an object of the present invention is to improve the accuracy of measuring the density of an adjustment toner image and to form an image at an appropriate density.

[0008] Technical means for solving technical problems

[0009] In order to solve the above-mentioned technical problems, an image forming apparatus according to a first aspect of the present application includes a belt unit, a photosensitive drum, a sensor, and a control unit.

[0010] The belt unit has an endless belt and a belt memory, wherein the belt memory stores belt information including at least one of belt manufacturer information, belt category information, and belt usage history information. The photosensitive drum faces the belt. The sensor has a light emitting element that emits light toward the belt and a light receiving element that can receive light reflected by the belt.

[0011] The control section can execute a correction process for correcting a value of a measured intensity of reflected light from a surface of the belt on which a toner image is not present, which is detected by the sensor.

[0012] When executing the correction process, the control unit corrects the value of the measured intensity of the reflected light based on the band information stored in the band memory.

[0013] Since the measured intensity value of the reflected light is corrected based on the band information, when the sensor detects the density of the adjustment toner image, the accuracy of the measured density of the adjustment toner image is improved compared to the case where the correction is not performed based on the band information. By improving the accuracy of the measured density of the adjustment toner image, an image can be formed at an appropriate density.

[0014] In addition, the image forming apparatus according to the second embodiment may be an image forming apparatus according to the first embodiment, wherein the control unit is capable of executing a density adjustment process for adjusting the density of a toner image formed on a sheet during printing. Then, the density adjustment process may include the following processes: forming an adjustment toner image of toner on a belt; irradiating light to the surface of the belt and the adjustment toner image using a light emitting element, detecting a first reflected light from the surface of the belt and a second reflected light from the adjustment toner image using a light receiving element; and comparing a measured intensity value of the corrected first reflected light obtained by the correction process with a measured intensity value of the second reflected light to determine a parameter value for adjusting the density of the toner image.

[0015] The control unit adjusts the density of the toner image by comparing the measured intensity value of the first reflected light corrected by the correction processing based on the measured intensity value of the band information corrected reflected light with the measured intensity value of the second reflected light. Therefore, the accuracy of the measured density of the adjustment toner image is improved.

[0016] In addition, the image forming device involved in the third embodiment may be an image forming device of the second embodiment, wherein the intensity of the regular reflection light from the belt is set to B1, the intensity of the diffuse reflection light from the belt is set to B2, the intensity of the regular reflection light from the adjustment toner image is set to P1, the intensity of the diffuse reflection light from the adjustment toner image is set to P2, the correction coefficient of the measured intensity value of the regular reflection light is set to Gsp, the control unit calculates ΔB=B1×Gsp-B2, ΔP=P1×Gsp-P2, determines the measured concentration of the adjustment toner image by comparing ΔB and ΔP, and determines the parameter value based on the measured concentration.

[0017] Furthermore, the image forming apparatus according to the fourth aspect may be the image forming apparatus according to the first aspect, wherein the correction coefficient Gsp is determined based on the belt information, and the control unit corrects the measured intensity value of the reflected light using the determined correction coefficient Gsp.

[0018] Furthermore, the image forming apparatus according to the fifth aspect may be the image forming apparatus according to the fourth aspect, wherein, when it is determined that the belt unit has been replaced, the control unit changes the correction coefficient Gsp based on the belt information stored in the belt memory.

[0019] When it is determined that the belt unit has been replaced, the control section changes the correction coefficient based on the belt information stored in the belt memory. Therefore, even when the belt unit has been replaced, it is possible to suppress a decrease in the accuracy of the measured density of the adjustment toner image.

[0020] Furthermore, in the image forming apparatus according to the sixth aspect, in the image forming apparatus according to the first aspect, the manufacturer information may be information indicating a manufacturer that manufactured the tape.

[0021] Furthermore, in the image forming apparatus according to the seventh aspect, in the developer cartridge of the first aspect, the type information may be information indicating whether the belt is a standard type, a long life type, or a low cost type.

[0022] Furthermore, the image forming apparatus according to the eighth aspect may be the image forming apparatus according to the first aspect, wherein the use history information is information indicating whether the tape is new or reused.

[0023] Effects of the Invention

[0024] According to the present invention, it is possible to improve the detection accuracy of the density of the adjustment toner image and to form an image at an appropriate density. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a cross-sectional view of the image forming apparatus according to the embodiment.

[0026] Figure 2 It is a perspective view showing the belt unit and the sensor.

[0027] Figure 3 This is a block diagram showing the electrical connection among a control unit, a band memory, and a sensor.

[0028] Figure 4 (a) is a diagram showing regular reflection light and diffuse reflection light of light irradiated to the belt, Figure 4 (b) shows regular reflection light and diffuse reflection light of the light irradiated onto the adjustment toner image.

[0029] Figure 5 This is a graph showing the relationship between the density of the toner image in the black toner and the intensity of the reflected light.

[0030] Figure 6 This is a graph showing the relationship between the density of a toner image in color toner and the intensity of reflected light.

[0031] Figure 7 This is a flowchart showing the processing executed by the control unit when the power is turned on or the rear cover is closed.

[0032] Figure 8 This is a flowchart of the density adjustment process executed by the control unit.

[0033] Fig. 9 It is a table showing the relationship between the belt information and the correction value of the correction coefficient Gsp.

[0034] Explanation of symbols

[0035] 1 Image forming device

[0036] 10 Main body shell

[0037] 70 band unit

[0038] 73 belts

[0039] 75 with memory

[0040] 100 Control Department

[0041] 200 Sensors

[0042] 220 Light-emitting element

[0043] 230 First light receiving element

[0044] 240 A second light receiving element. DETAILED DESCRIPTION

[0045] Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.

[0046] like Figure 1 As shown in FIG. 1 , the image forming apparatus 1 is a color laser printer and includes a main body casing 10 , a supply unit 20 , an image forming unit 30 , and a discharge unit 90 .

[0047] The main body housing 10 includes a discharge tray 11 and a rear cover 12. The discharge tray 11 places the image-formed sheets S. The rear cover 12 is openable and closable, and when the rear cover 12 is opened, the belt unit 70 described later can be attached and detached.

[0048] The supply unit 20 includes a supply tray 21 and a sheet supply device 22 . The supply tray 21 is a tray for storing sheets S. The sheet supply device 22 conveys the sheets S in the supply tray 21 toward the image forming unit 30 .

[0049] The image forming section 30 includes four LED units 40 , four process cartridges 50 , a belt unit 70 , and a fixing device 80 .

[0050] The LED unit 40 includes a plurality of LEDs and exposes a photosensitive drum 51 to light, which will be described later.

[0051] The process cartridge 50 includes a photosensitive drum 51, a charger 52, a developing roller (not shown), a toner storage chamber, etc. In the process cartridge 50, process cartridges (not shown) containing black, cyan, magenta, and yellow toners are arranged in the order of 50K, 50C, 50M, and 50Y from the downstream side to the upstream side in the conveying direction of the sheet S. The photosensitive drum 51 faces the belt 73.

[0052] The belt unit 70 includes a driving roller 71 , a driven roller 72 , a belt 73 , four transfer rollers 74 , and a belt memory 75 .

[0053] The driving roller 71 and the driven roller 72 are rollers for rotating the belt 73. The driving roller 71 and the driven roller 72 are in contact with the inner peripheral surface of the belt 73.

[0054] The belt 73 is an endless belt that conveys the sheet S between the photosensitive drums 51. The outer peripheral surface of the belt 73 is in contact with the photosensitive drums 51. The transfer roller 74 sandwiches the belt 73 with the photosensitive drums 51.

[0055] The tape memory 75 is a memory for storing tape information, and the tape information includes at least one of the manufacturer information of the tape 73, the type information of the tape 73, and the usage history information of the tape 73. Figure 3 As shown, the tape memory 75 stores serial number, manufacturer information, category information, and usage history information as tape information.

[0056] like Fig. 9 As shown, the manufacturer information is information indicating the manufacturer that manufactured the belt 73. The category information is information indicating whether the belt 73 is a standard type, a long life type, or a low cost type. The usage history information is information indicating whether the belt 73 is a new product or a reused product.

[0057] The fixing device 80 includes a heating roller 81 and a pressure roller 82. The heating roller 81 includes a halogen heater 81A therein. The pressure roller 82 sandwiches the sheet S with the heating roller 81.

[0058] In the image forming section 30, first, the surface of the photosensitive drum 51 is charged by the charger 52 and then exposed by the LED unit 40. Thus, an electrostatic latent image is formed on the photosensitive drum 51. Thereafter, a toner image is formed on the photosensitive drum 51 by supplying toner to the electrostatic latent image from the developing roller.

[0059] Next, the sheet S supplied onto the belt 73 passes between the photosensitive drum 51 and the transfer roller 74, whereby the toner image formed on the photosensitive drum 51 is transferred onto the sheet S. Then, the sheet S passes between the heating roller 81 and the pressure roller 82, whereby the toner image transferred onto the sheet S is thermally fixed.

[0060] The discharge unit 90 is configured to convey the sheet S discharged from the fixing device 80 to the outside of the main body housing 10. The discharge unit 90 includes a conveying roller 91 and a discharge roller 92. The sheet S discharged from the fixing device 80 is conveyed by the conveying roller 91 to the discharge roller 92, and discharged to the discharge tray 11 by the discharge roller 92.

[0061] like Figure 1 and Figure 3 As shown, the image forming apparatus 1 further includes a control unit 100 and a sensor 200 .

[0062] The control unit 100 includes a CPU, RAM, ROM, nonvolatile memory, ASIC, input / output circuits, etc. The control unit 100 performs control by performing various calculations based on print commands, signals input from the sensor 200 , and programs and data stored in ROM, etc.

[0063] The sensor 200 is mounted on the main body housing 10 of the image forming apparatus 1. Figure 2 , Figure 4 As shown in (a) and (b) of FIG. 7 , the sensor 200 is arranged to face the surface of the belt 73. The sensor 200 is a sensor for detecting the position and density of the adjustment toner image P formed on the surface of the belt 73.

[0064] like Figure 4 As shown in (a) and (b) of FIG. 1 , the sensor 200 includes a substrate 210, a light emitting element 220, a first light receiving element 230, and a second light receiving element 240. The light emitting element 220, the first light receiving element 230, and the second light receiving element 240 are mounted on the substrate 210. The first light receiving element 230 and the second light receiving element 240 are examples of light receiving elements.

[0065] The light emitting element 220 emits light toward the belt 73 or the adjustment toner image P. The light emitting element 220 is, for example, an LED.

[0066] The first light receiving element 230 and the second light receiving element 240 can receive light emitted from the light emitting element 220 and reflected by the belt 73 or the adjustment toner image P. The first light receiving element 230 and the second light receiving element 240 are photodiodes sensitive to the wavelength of light emitted from the light emitting element 220, for example.

[0067] The first light receiving element 230 is located at a position where the regular reflection component of the light reflected by the belt 73 or the adjustment toner image P is incident, that is, at a position where the light irradiated from the light emitting element 220 toward the adjustment toner image P, the light having an equal incident angle and a reflection angle with respect to the adjustment toner image P, is incident. The first light receiving element 230 can receive the light emitted by the light emitting element 220 and regularly reflected by the belt 73 or the adjustment toner image P.

[0068] The second light receiving element 240 is located at a position where the diffuse reflection component of the light reflected by the belt 73 or the adjustment toner image P is incident, that is, at a position where the light component other than the regular reflection component of the light irradiated from the light emitting element 220 toward the adjustment toner image P is incident. The second light receiving element 240 can receive the light that is emitted from the light emitting element 220 and diffusely reflected by the belt 73 or the adjustment toner image P.

[0069] Figure 5 This is a graph showing the relationship between the density of the toner image of the black toner and the intensity P1 of the regular reflection light and the intensity P2 of the diffuse reflection light. In the black toner, as the density of the toner image increases, the intensity P1 of the regular reflection light decreases, while the intensity P2 of the diffuse reflection light increases little by little. When the density of the toner image reaches a certain density or above, the intensity P1 of the regular reflection light and the intensity P2 of the diffuse reflection light both hardly change and become constant values.

[0070] Figure 6 This is a graph showing the relationship between the density of a color toner image and the intensity P1 of regular reflection light and the intensity P2 of diffuse reflection light. Figure 6 This is a diagram of magenta toner, but yellow and cyan also show almost the same relationship, so only magenta is shown as a representative. In color toner, the higher the concentration of the toner image becomes, the smaller the intensity P1 of the regular reflection light becomes, and at a certain concentration it turns into a slow rise. In contrast, the intensity P2 of the diffuse reflection light increases little by little as the concentration of the toner image increases, and increases at the same ratio after overlapping with the intensity P1 of the regular reflection light. The place where the intensity P1 of the regular reflection light overlaps with the intensity P2 of the diffuse reflection light is after the intensity P1 of the regular reflection light turns into a slow rise.

[0071] The control unit 100 can execute a density adjustment process for adjusting the density of a toner image formed on the sheet S during printing. Here, a procedure for the control unit 100 to execute the density adjustment process will be described.

[0072] The concentration adjustment process includes: forming an adjustment toner image P of toner on the belt 73; irradiating the surface of the belt 73 and the adjustment toner image P with light using the light-emitting element 220, detecting a first reflected light from the surface of the belt 73 and a second reflected light from the adjustment toner image P using the first light-receiving element 230 and the second light-receiving element 240; and comparing the measured intensity value of the corrected first reflected light obtained by the correction process with the measured intensity value of the second reflected light to determine a parameter value for adjusting the concentration of the toner image.

[0073] In addition, although the control unit 100 performs density adjustment processing for each of black, cyan, magenta, and yellow, the steps for each color are the same, and therefore, the density adjustment processing for black toner will be representatively described, and descriptions of other colors will be omitted.

[0074] First, if Figure 2 As shown in FIG. 1 , the control unit 100 forms an adjustment toner image P on the surface of the belt 73. Then, as shown in FIG. Figure 4 As shown in (a) of FIG. 1 , the control unit 100 irradiates light onto the surface of the belt 73, and detects the intensity B1 of the regular reflection light from the surface of the belt 73 and the intensity B2 of the diffuse reflection light from the surface of the belt 73. Figure 4 As shown in (b), the control unit 100 irradiates light to the adjustment toner image P formed on the surface of the belt 73, and detects the intensity P1 of the regular reflection light from the adjustment toner image P and the intensity P2 of the diffuse reflection light from the adjustment toner image P.

[0075] Next, the control unit 100 performs a correction process for correcting the measured intensity value of the reflected light detected by the sensor 200, and determines the measured density of the adjustment toner image P. Specifically, the control unit 100 sets the correction coefficient of the measured intensity value of the regular reflected light as Gsp, and performs the following calculation:

[0076] ΔB=B1×Gsp-B2

[0077] ΔP=P1×Gsp-P2

[0078] Then, the measured density of the adjustment toner image P is determined by comparing ΔB and ΔP.

[0079] When executing the correction process, the control unit 100 corrects the value of the measured intensity of the reflected light based on the belt information stored in the belt memory 75. Specifically, the correction coefficient Gsp is a coefficient determined by measuring each image forming apparatus before the image forming apparatus 1 is shipped, but when the belt 73 is replaced after shipping, correction is performed based on the belt information. For example, when the manufacturer information of the belt 73 is company A, the category information is standard type, and the belt 73 is a new product, the correction coefficient Gsp at the time of shipping is maintained, but when any of the belt information is changed due to the replacement of the belt 73, the correction coefficient Gsp at the time of shipping is corrected. Fig. 9 The table shown shows an example of the correction value of the correction coefficient Gsp when the belt information is changed. For example, when the manufacturer information of the belt 73 is company B, the category information is standard type, and it is a new product, refer to Fig. 9 According to the table, the correction coefficient Gsp is increased by +2 relative to the factory value.

[0080] When the image forming apparatus 1 is powered on or the rear cover 12 is closed, the belt unit 70 may be replaced, so the control unit 100 reads the belt information from the belt memory 75. When the control unit 100 determines that the belt unit 70 has been replaced, it changes the correction coefficient Gsp (see Fig. 9 ).

[0081] The control unit 100 calculates the measured density of the adjustment toner image P based on ΔB and ΔP. Specifically, the measured density is calculated based on a density table corresponding to ΔB / ΔP. The density table corresponding to ΔB / ΔP is prepared in advance based on experiments and simulations and stored in the storage unit of the image forming apparatus 1.

[0082] The control unit 100 determines a parameter value for adjusting the toner density during image formation based on the calculated measured density. The parameter value for adjusting the toner density is determined for each of black, cyan, magenta, and yellow.

[0083] Next, refer to Figure 7 An example of the process executed by the control unit 100 when the image forming apparatus 1 is powered on or the rear cover 12 is closed will be described with reference to the flowchart of FIG.

[0084] like Figure 7 As shown, the control unit 100 determines whether the power of the image forming apparatus 1 is turned on or the rear cover 12 is closed ( S1 ).

[0085] In step S1 , when the control unit 100 determines that the image forming apparatus 1 is powered on or the rear cover 12 is closed ( S1 , Yes), the control unit 100 reads the tape information from the tape memory 75 because the tape unit 70 may have been replaced ( S2 ).

[0086] After step S2, the control unit 100 determines whether the tape 73 has been replaced (S3). The control unit 100 determines that the tape 73 has been replaced when the serial number of the tape information is different from the previous one.

[0087] In step S3 , when the control unit 100 does not determine that the belt 73 has been replaced ( S3 , No), since there is no need to correct the correction coefficient Gsp, the process ends.

[0088] On the other hand, in step S3 , when the control unit 100 determines that the belt 73 has been replaced ( S3 , Yes), the control unit 100 determines the correction coefficient Gsp based on the belt information read from the belt memory 75 .

[0089] Next, refer to Figure 8 An example of a process in which the control unit 100 executes the density adjustment process will be described with reference to the flowchart of FIG.

[0090] When executing the density adjustment process, the control section 100 forms an adjustment toner image P on the belt 73 ( S11 ).

[0091] After step S11, control unit 100 irradiates light from light emitting element 220 onto the surface of tape 73, and detects intensity B1 of regular reflected light from tape 73 and intensity B2 of diffuse reflected light from tape 73 from first light receiving element 230 and second light receiving element 240 (S12).

[0092] After step S12, the control unit 100 irradiates light from the light emitting element 220 toward the adjustment toner image P formed on the surface of the belt 73, and detects the intensity P1 of the direct reflected light from the adjustment toner image P and the intensity P2 of the diffuse reflected light from the adjustment toner image P from the first light receiving element 230 and the second light receiving element 240 (S13).

[0093] After step S13, the control unit 100 sets the correction coefficient of the measured intensity value of the regular reflected light as Gsp, calculates ΔB=B1×Gsp-B2 and ΔP=P1×Gsp-P2, and determines the measured density of the adjustment toner image P by comparing ΔB and ΔP (S14). The process of step S14 is an example of correction processing.

[0094] After step S14 , the control unit 100 calculates the measured density of the adjustment toner image P based on ΔB and ΔP ( S15 ).

[0095] After step S15, the control unit 100 determines a parameter value for adjusting the toner density during image formation based on the calculated measurement density, and ends the process (S16).

[0096] As described above, according to the embodiment, the following effects can be obtained.

[0097] Conventionally, when the density of the adjustment toner image P is detected, the density is calculated without taking into account the belt information of the belt used in the belt unit 70 , and therefore the accuracy of the measured density may be low.

[0098] However, according to the image forming apparatus 1, the value of the measured intensity of the reflected light is corrected based on the tape information stored in the tape memory 75. Therefore, when the sensor 200 detects the density of the adjustment toner image P, the detection accuracy of the measured density of the adjustment toner image P is improved compared to the case where the correction is not performed based on the tape information. By improving the detection accuracy of the measured density of the adjustment toner image P, it is possible to form an image at an appropriate density.

[0099] In addition, the control unit 100 adjusts the density of the toner image by comparing the measured intensity value of the first reflected light obtained by the correction processing based on the measured intensity value of the band information corrected reflected light with the measured intensity value of the second reflected light. Therefore, the accuracy of the measured density of the adjustment toner image P is improved.

[0100] When the control unit 100 determines that the belt unit 70 has been replaced, it changes the correction coefficient Gsp based on the belt information stored in the belt memory 75. Therefore, even when the belt unit 70 has been replaced, the accuracy of the measured density of the adjustment toner image P can be suppressed from being reduced.

[0101] In addition, the present invention is not limited to the above-mentioned embodiment, and can be used in various forms as exemplified below.

[0102] In the above-mentioned embodiment, the manufacturer information is information indicating the manufacturer that manufactured the belt 73 , but the manufacturer information may also include information such as the place and equipment where the belt 73 is manufactured.

[0103] In the above-described embodiment, the type information is information indicating whether the belt 73 is a standard type, a long-life type, or a low-cost type. However, the type information may include other information indicating the type of the belt, such as the material or quality of the belt.

[0104] In the above-mentioned embodiment, the usage history information is information indicating whether the belt is new or reused, but the usage history information may include other information indicating the usage history of the belt, such as the usage time of the belt and the usage rotation speed of the belt.

[0105] In the above-mentioned embodiment, by Fig. 9 The table shown in FIG. 1 shows an example of the correction value of the correction coefficient Gsp when the belt information is changed. Fig. 9 The table is only an example, and the correction value can be changed appropriately.

[0106] In the above-described embodiment, the image forming apparatus 1 is a color laser printer, but the present invention can also be applied to other image forming apparatuses such as a monochrome laser printer, a copier, a multifunction peripheral, and the like.

[0107] The respective elements described in the above-mentioned embodiment and modified examples may be implemented in any combination.

Claims

1. An image forming device, characterized in that: have: a tape unit having an endless tape and a tape memory storing tape information including at least one of tape manufacturer information, tape type information, and tape usage history information; a photosensitive drum opposite to the belt; a sensor having a light emitting element for emitting light toward the belt and a light receiving element for receiving light reflected by the belt; as well as Control Department, The control unit is capable of executing a correction process for correcting a value of a measured intensity of reflected light detected by the sensor from a surface of the belt having no toner image, When executing the correction process, the control unit corrects the value of the measured intensity of the reflected light based on the band information stored in the band memory.

2. The image forming apparatus according to claim 1, wherein: The control unit is capable of executing a density adjustment process for adjusting the density of a toner image formed on a sheet during printing. The concentration adjustment process includes the following processes: forming a toner image for adjustment of the toner on the belt; irradiating the surface of the belt and the adjustment toner image with light by the light emitting element, and detecting the first reflected light from the surface of the belt and the second reflected light from the adjustment toner image by the light receiving element; as well as The measured intensity value of the first reflected light after correction obtained by the correction process is compared with the measured intensity value of the second reflected light, and a parameter value for adjusting the density of the toner image is determined.

3. The image forming apparatus according to claim 2, wherein: The intensity of the regular reflection light from the belt is set to B1, the intensity of the diffuse reflection light from the belt is set to B2, the intensity of the regular reflection light from the adjustment toner image is set to P1, the intensity of the diffuse reflection light from the adjustment toner image is set to P2, and the correction coefficient of the measured intensity value of the regular reflection light is set to Gsp, and the control unit performs the following calculation: ΔB=B1×Gsp-B2, ΔP=P1×Gsp-P2, The measured density of the adjustment toner image is determined by comparing ΔB and ΔP, and the parameter value is determined based on the measured density.

4. The image forming apparatus according to claim 1, wherein: The control unit determines a correction coefficient Gsp based on the belt information. The control unit corrects the measured intensity value of the reflected light using the determined correction coefficient Gsp.

5. The image forming apparatus according to claim 4, wherein: When it is determined that the belt has been replaced, the control unit changes the correction coefficient Gsp based on the belt information stored in the belt memory.

6. The image forming apparatus according to claim 1, wherein: The manufacturer information is information indicating the manufacturer that manufactured the belt.

7. The image forming apparatus according to claim 1, wherein: The type information is information indicating whether the tape is a standard type, a long life type, or a low cost type.

8. The image forming apparatus according to claim 1, wherein: The usage history information is information indicating whether the tape is new or reused.

Images