BACKGROUND

[0001] A fuser in an image forming apparatus may fix a toner image to a printing medium, such as paper, on which the toner image has been formed. Based on a wrap jam occurring, for example, if the paper is wrapped along a fuser belt, the fuser belt and a roller in the fuser may be damaged. Accordingly, a sensor for detecting a wrap jam may be mounted on the image forming apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

[0002] Various examples will be described below by referring to the following figures.

[0003] FIG. 1 is a conceptual diagram illustrating an operation in which an image forming apparatus compensates for a detection value of a light sensor based on temperature information of a temperature sensor in a case where the detection value of the light sensor satisfies a correction condition, according to an example;

[0004] FIG. 2 is a block diagram of an image forming apparatus, according to an example;

[0005] FIG. 3 is a block diagram of an image forming apparatus, according to another example;

[0006] FIG. 4 is a flowchart illustrating an operating method of an image forming apparatus to correct a light emission amount of a light sensor based on temperature information of a temperature sensor in a case where a detection value of the light sensor satisfies a correction condition for correcting the light emission amount of the light sensor, according to an example;

[0007] FIG. 5 is a flowchart illustrating an operating method of an image forming apparatus to correct a light emission amount of a light sensor based on temperature information of a temperature sensor, according to an example; [0008] FIG. 6 shows graphs respectively illustrating a temperature compensation (TC) value of a temperature sensor and a detection value of a light sensor, according to an example;

[0009] FIG. 7 is a graph illustrating a detection value of a light sensor based on a light emission amount of the light sensor not being corrected, according to an example;

[0010] FIG. 8 is a graph illustrating a detection value of a light sensor based on a light emission amount of the light sensor being corrected, according to an example;

[0011] FIG. 9 is a graph illustrating a temperature detection (TD) value and a TC value of a temperature sensor, according to an example; and [0012] FIG. 10 is a diagram illustrating instructions stored in a computer- readable storage medium, according to an example.

DETAILED DESCRIPTION

[0013] hereinafter, examples of the disclosure will be described with reference to the accompanying drawings. However, the disclosure may be implemented in various different forms and is not limited to the examples described herein.

[0014] An "image forming apparatus" may refer to any type of apparatus capable of performing an image forming operation, such as a printer, a copier, a scanner, a fax machine, a multi-function printer (MFP), or a display apparatus. Also, the image forming apparatus may be a two-dimensional (2D) image forming apparatus or a three-dimensional (3D) image forming apparatus. An "image forming operation performed by the image forming apparatus" may refer to an operation related to printing, copying, scanning, faxing, storage, transmission, coating, etc., and may be a combination of at least two of the operations.

[0015] A "light sensor" may refer to a sensor for detecting an event in which a printing medium, such as paper, is wrapped in a fuser. For example, the light sensor may include a light emitting element and a light receiving element. For example, since a light receiving value with respect to the paper is large compared to a light receiving value with respect to a fuser belt, an event in which the paper is wrapped in the fuser may be detected based on the light receiving value detected by the light receiving element of the light sensor. Since characteristics of the light emitting element of the light sensor change according to heat, a light emission amount according to a temperature may change. Accordingly, in the light sensor, calibration to correct a change in the light emission amount of the light emitting element of the light sensor may be performed.

[0016] A “correction condition” may be a condition for correcting the light emission amount of the light emitting element of the light sensor. For example, the correction condition may be a condition for detecting a time in which a detection value of the light sensor does not satisfy a preset reference range. For example, based on the detection value of the light sensor being lower than a lower limit of the preset reference range, a detection power of the light sensor deteriorates, and thus an operation of compensating for the detection value of the light sensor may be performed.

[0017] A “temperature sensor” may be a sensor that detects a temperature. In an example, the temperature sensor may detect a temperature of the fuser. For example, the temperature sensor may be a non-contact temperature sensor. A temperature of the fuser may be the temperature of the fuser, the fuser belt, a surrounding of the fuser, etc. Temperature information of the temperature sensor may include a temperature compensation (TC) value indicating a value obtained by measuring a temperature of the temperature sensor, and a temperature detection (TD) value indicating a value obtained by measuring a temperature of the fuser. Also, the temperature information obtained from the temperature sensor during calibration of the light sensor may be referred to as reference temperature information.

[0018] FIG. 1 is a conceptual diagram illustrating an operation in which an image forming apparatus compensates for a detection value of a light sensor based on temperature information of a temperature sensor in which the detection value of the light sensor satisfies a correction condition, according to an example. FIG. 2 is a block diagram of an image forming apparatus, according to an example. [0019] Referring to an image 110 of FIG. 1 , an image forming apparatus 10 may include a fuser 210 to fix a toner to a printing medium (hereinafter “paper”) 310. The fuser 210 may include a fuser belt 301 , a fuser heater 302, a pressing roller 303, and a driving device 304. The paper 310 may pass between the fuser belt 301 and the pressing roller 303 in the fuser 210. Based on the paper 310 being wrapped on the fuser belt 301 or the pressing roller 303, since the fuser belt 301 and the pressing roller 303 may be damaged, the image forming apparatus 10 may use a light sensor 220 to detect an event in which the paper 310 is wrapped. An event in which the paper 310 is wound on the fuser belt 301 or the pressing roller 303 may be referred to as a wrap jam. For example, based on a light receiving value of a light receiving element of the light sensor 220 increasing, the image forming apparatus 10 may detect the wrap jam.

[0020] Based on the fuser 210 of the image forming apparatus 10 operating, the fuser heater 302 may generate heat. Because the heat is generated by the fuser heater 302, a temperature of the fuser 210 may increase. Since characteristics of a light emitting element of the light sensor 220 change according to the heat, in a case where the temperature of the fuser 210 increases, a light emission amount of the light emitting element of the light sensor 220 may be reduced, and a detection power function of the light sensor 220 may deteriorate. Accordingly, in order to avoid reducing the light emission amount of the light emitting element of the light sensor 220 according to an increase in the temperature of the fuser 210, the image forming apparatus 10 may correct the light emission amount of the light emitting element.

[0021] Referring to block 101 of FIG. 1 , the image forming apparatus 10 may monitor a detection value of the light sensor 220. For example, in a case where the temperature of the fuser 210 increases, the detection value of the light sensor 220 may decrease. In a case where the detection value of the light sensor 220 deviates from a reference range, the detection power function of the light sensor 220 may deteriorate, and the image forming apparatus 10 may not detect the wrap jam.

[0022] Referring to block 102 of FIG. 1 , in a case where the detection value of the light sensor 220 satisfies a correction condition, the image forming apparatus 10 may compensate for the detection value of the light sensor 220 based on the temperature information of a temperature sensor 230. An example process of compensating for the detection value of the light sensor 220 will be described with reference to FIGS. 2 to 5. The image 120 of FIG. 1 shows a graph in which the detection value of the light sensor 220 is compensated, whereby the detection value of the light sensor 220 is detected within the reference range. [0023] As illustrated in FIG. 2, the image forming apparatus 10 may include the fuser 210, the light sensor 220, the temperature sensor 230, a memory 240, and a processor 250. Flowever, the illustrated components are not indispensable components. The image forming apparatus 10 may be implemented by more components than the illustrated components, and the image forming apparatus 10 may be implemented by fewer components hereinafter, examples of the components will be described.

[0024] The fuser 210 may fix a toner on a paper. The fuser 210 may fix the toner deposited on the paper using pressure and heat. For example, the fuser 210 may include the fuser belt 301 and the fuser heater 302. In an example, the fuser heater 302 may include a heating lamp. Based on heat being generated by the fuser heater 302, the fuser belt 301 may be heated. For example, the fuser belt 301 may rotate in engagement with the pressing roller 303, and the toner may be fixed to the paper because the paper passes between the fuser belt 301 and the pressing roller 303.

[0025] The light sensor 220 may detect an event in which the paper is wrapped in the fuser 210. For example, the event in which the paper is wrapped in the fuser 210 may be an event in which the paper is wound on the fuser belt 301 or the pressing roller 303 pressing the toner to the paper. For example, the light sensor 220 may detect an event in which the paper is wrapped on the fuser belt 301.

[0026] For example, the light sensor 220 may include a light emitting element and a light receiving element. For example, the light emitting element may include a light emitting diode (LED), and the light receiving element may include a photo transistor. For example, the light emitting element of the light sensor 220 may irradiate light to the fuser belt 301 , and the light receiving element of the light sensor 220 may receive light reflected from the fuser belt 301. For example, the light emitting element of the light sensor 220 may transmit a light emission value indicating a light emission amount to the processor 250. In addition, the light receiving element of the light sensor 220 may transmit a light receiving value indicating a light receiving amount to the processor 250.

[0027] A light receiving value of the paper wound around the fuser belt 301 may be relatively large compared to a light receiving value of the fuser belt 301. Accordingly, based on the light receiving value detected by the light receiving element being greater than the light receiving value with respect to the fuser belt 301 , the processor 250 may detect that the event in which the paper is wrapped in the fuser belt 301 has occurred.

[0028] In addition, since characteristics of the light emitting element of the light sensor 220 change according to heat, based on the temperature of the fuser 210 increasing, the light emission amount of the light emitting element of the light sensor 220 may be reduced. Accordingly, in order to avoid decreasing the light emission amount of the light emitting element of the light sensor 220 according to an increase in the temperature of the fuser 210, the processor 250 may correct the light emission amount of the light emitting element.

[0029] The temperature sensor 230 may detect a temperature of the fuser 210. For example, the temperature of the fuser 210 may be the temperature of the fuser 210, the fuser belt 301 , a surrounding of the fuser 210, etc. For example, the temperature sensor 230 may detect the temperature of the fuser belt 301 from a measured value. The temperature sensor 230 may be installed in the surroundings of the fuser 210. For example, the temperature sensor 230 may be installed within a certain distance from the fuser 210. The temperature sensor 230 may obtain a temperature detection (TD) value indicating a value obtained by measuring the temperature of the fuser belt 301 and a temperature compensation (TC) value indicating a value obtained by measuring the temperature of the temperature sensor 230. An actual temperature of the fuser belt 301 may be detected based on the TD value and the TC value. For example, the actual temperature of the fuser belt 301 may be detected according to a temperature characteristic table of the TD value and the TC value.

[0030] The memory 240 may store machine readable instructions, a program, etc. For example, the memory 240 may store a program including instructions for an operating method of the image forming apparatus 10 to correct the light emission amount of the light sensor 220 based on temperature information of the temperature sensor 230 in a case where the detection value of the light sensor 220 in the image forming apparatus 10 satisfies a correction condition for correcting the light emission amount of the light sensor 220. Also, the memory 240 may store sensing information obtained from the light sensor 220 or the temperature sensor 230.

[0031] The memory 240 may include a storage medium such as a flash memory type memory, a hard disk type memory, a multimedia card micro type memory, a card type memory (e.g., SD orXD memory), Random Access Memory (RAM), Static Random Access Memory (SRAM), Read-Only Memory (ROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Programmable Read-Only Memory (PROM), magnetic memory, magnetic disk, optical disk, etc.

[0032] The processor 250 is to control an operation of the image forming apparatus 10 and may include a processor such as a central processing unit (CPU). The processor 250 may include a processor specialized for each function or may be a single integrated processor.

[0033] The processor 250 may execute a program stored in the memory 240, read data or files stored in the memory 240, or store new data or files in the memory 240. The processor 250 may perform an operation for compensating for the detection value of the light sensor 220 according to the temperature of the fuser 210 by executing the instructions stored in the memory 240.

[0034] The processor 250 may receive a detection signal or detection information obtained from the light sensor 220 or the temperature sensor 230 from the light sensor 220 or the temperature sensor 230, respectively. The processor 250 may control an operation of the fuser 210, the light sensor 220, or the temperature sensor 230 based on a result of calculating the detection signal or the detection information obtained from the light sensor 220 or the temperature sensor 230.

[0035] The processor 250 may confirm whether the detection value sensed by the light sensor 220 satisfies a correction condition for correcting the light emission amount of the light sensor 220. Based on the detection value of the light sensor 220 satisfying the correction condition, the processor 250 may correct the light emission amount of the light sensor 220 based on the temperature information of the temperature sensor 230.

[0036] The processor 250 may perform calibration to compensate for a detection power of the light sensor 220. The processor 250 may obtain reference temperature information including reference temperature values of the fuser 210 and the temperature sensor 230 from the temperature sensor 230 during calibration. The processor 250 may store the reference temperature information in the memory 240. The processor 250 may obtain temperature information including a temperature value of the temperature sensor 230 based on the detection value of the light sensor 220 satisfying the correction condition. The processor 250 may correct the light emission amount of the light sensor 220 based on the reference temperature information and the temperature information of the temperature sensor 230.

[0037] For example, the reference temperature value may include a reference TC value indicating a value obtained by measuring the temperature of the temperature sensor 230 during calibration, and a reference TD value indicating a value obtained by measuring the temperature of the fuser belt 301 in the temperature sensor 230 during calibration. The memory 240 may store the reference TD value, the reference TC value, and a reference difference value indicating a difference between the reference TD value and the reference TC value.

[0038] For example, the compensation condition may be a condition in which the detection value of the light sensor 220 is less than a lower limit value of a preset reference range. For example, the preset reference range may be a range set to normally detect an event in which the detection power of the light sensor 220 does not deteriorate and the paper is wrapped in the fuser 210. [0039] The processor 250 may obtain the TC value and the TD value of the temperature sensor 230 at a time in which the detection value of the light sensor 220 satisfies the correction condition. The memory 240 may store the TC value and the TD value of the temperature sensor 230 in the memory 240. Also, the memory 240 may store a target difference value indicating a difference between the TC value and the TD value of the temperature sensor 230 at the time based on the detection value of the light sensor 220 satisfies the correction condition. [0040] The processor 250 may calculate an offset value of a parameter controlling the light emission amount of the light sensor 220 based on the difference between the reference temperature value and the temperature value of the temperature sensor 230. The processor 250 may control the light emission amount of the light sensor 220 based on the offset value of the parameter. For example, the parameter may be a parameter to control a duty ratio through pulse width modulation (PWM) of a light emitting element of the light sensor 220. [0041] For example, the processor 250 may obtain a reference difference value indicating a difference between the reference TC value and the reference TD value of the temperature sensor 230 during calibration. The processor 250 may obtain a target difference value indicating a difference between the TC value and the TD value of the temperature sensor 230 at a time in which the detection value of the light sensor 220 satisfies the correction condition. The processor 250 may calculate a first offset value of the parameter based on a result of comparing the reference difference value with the target difference value.

[0042] For example, the processor 250 may detect whether the difference between the target difference value and the reference difference value is greater than or equal to A. Flere, A is a constant and may be preset. In a case where the difference between the target difference value and the reference difference value is greater than or equal to A, the processor 250 may calculate a value obtained by dividing the difference between the target difference value and the reference difference value by A as the first offset value. In a case where the difference between the target difference value and the reference difference value is less than A, the processor 250 may monitor whether the detection value of the light sensor 220 satisfies the correction condition.

[0043] For example, the processor 250 may calculate a second offset value of the parameter based on a result of comparing the reference TC value of the temperature sensor 230 with the TC value of the temperature sensor 230. For example, the processor 250 may detect whether the difference between the TC value and the reference TC value is greater than or equal to B. Flere, B is a constant and may be preset. In a case where the difference between the TC value and the reference TC value is greater than or equal to B, the processor 250 may calculate a value obtained by dividing the difference between the TC value and the reference TC value by B as the second offset value. In a case where the difference between the TC value and the reference TC value is less than B, the processor 250 may monitor whether the detection value of the light sensor 220 satisfies the correction condition.

[0044] For example, the processor 250 may correct a value of the parameter by adding the first offset value and the second offset value to the existing value of the parameter.

[0045] The processor 250 may maintain the value of the parameter controlling the light emission amount of the light sensor 220 based on the detection value sensed by the light sensor 220 satisfying the preset reference range, according to the correction of the light emission amount of the light sensor 220.

[0046] Based on the temperature of the fuser 210 increasing, in order to perform calibration of the light sensor 220, it may take time to obtain the light emission amount of the light emitting element and the light receiving amount of the light receiving element of the light sensor 220, and calculate an amount of change in the light emission amount and the light receiving amount. Accordingly, based on the detection value of the light sensor 220 satisfying the correction condition, the image forming apparatus 10 may detect that the temperature of the fuser 210 has increased and correct the light emission amount of the light sensor 220 using the temperature information of the temperature sensor 230. The light emission amount of the light sensor 220 is corrected, thereby compensating for the detection value of the light sensor 220, and preventing deterioration of the performance of the image forming apparatus 10.

[0047] FIG. 3 is a block diagram of an image forming apparatus, according to another example.

[0048] Elements comprising the image forming apparatus 10 illustrated in FIG. 2 may correspond to those of the image forming apparatus 10 illustrated in FIG. 3. Referring to FIG. 3, the fuser 210 may include the fuser belt 301 , the fuser heater 302, the pressing roller 303, and the driving device 304. The paper 310 may pass between the fuser belt 301 and the pressing roller 303 in the fuser 210. [0049] Based on the fuser 210 of the image forming apparatus 10 operating, the fuser heater 302 may generate heat, and the fuser belt 301 may be heated. Accordingly, a temperature of the fuser 210 may increase. Since a characteristic of a light emitting element of the light sensor 220 may change, a light emission amount of the light emitting element of the light sensor 220 may be reduced due to an increase in the temperature of the fuser 210. In this case, the image forming apparatus 10 may perform calibration to correct the reduced light emission amount. The image forming apparatus 10 may perform calibration based on a result of reading a change in the light emission amount and a light receiving amount of the light sensor 220. Since it takes time to read the changes in the light emission amount and the light receiving amount of the light sensor 220, the image forming apparatus 10 may correct the light emission amount of the light sensor 220 based on temperature information of the temperature sensor 230. Accordingly, the image forming apparatus 10 may prevent a decrease in the speed of an image forming operation by correcting the light emission amount of the light sensor 220 based on the temperature information of the temperature sensor 230, instead of performing calibration.

[0050] For example, the temperature sensor 230 may obtain a TD value indicating a value obtained by measuring a temperature of the fuser belt 301 and a TC value indicating a value obtained by measuring a temperature of the temperature sensor 230. For example, the temperature sensor 230 may transmit the TD value and the TC value to the processor 250. The processor 250 may calculate an actual temperature of the fuser belt 301 with reference to a temperature characteristic table of the temperature sensor 230. For example, the temperature characteristic table may be prepared in advance according to a type of the temperature sensor 230, a type of a reflector, etc. Flere, the reflector may be the fuser belt 301 .

[0051] Because the temperature of the fuser 210 increases, the TD value and the TC value of the temperature sensor 230 may decrease, and the TD value may increase compared to the TC value. That is, because the temperature of the fuser 210 increases, a difference between the TD value and the TC value may increase. The processor 250 may detect an amount of change in the temperature of the fuser 210 based on the difference value between the TD value and the TC value of the temperature sensor 230 and correct the light emission amount of the light emitting element of the light sensor 220.

[0052] In addition, based on the fuser heater 302 being heated for a certain time, even if the difference between the TD value and the TC value of the temperature sensor 230 is not large, a temperature of a surrounding of the fuser 210 steadily increases, and thus the light emission amount of the light emitting element of the light sensor 220 may be reduced. In this case, based on a compensation value changing by more than a reference compensation value, the processor 250 may correct the light emission amount of the light emitting element of the light sensor 220 based on the difference value between the TD value and the TC value. The light emission amount of the light sensor 220 is corrected, thereby reducing or preventing deterioration of a detection power of the light sensor 220 and damage to the fuser belt 301 or the pressing roller 303.

[0053] FIG. 4 is a flowchart illustrating an operating method of an image forming apparatus to correct a light emission amount of a light sensor based on temperature information of a temperature sensor in a case where a detection value of the light sensor satisfies a correction condition for correcting the light emission amount of the light sensor, according to an example.

[0054] Referring to FIG. 4, the image forming apparatus 10 may perform calibration for compensating for a detection power of the light sensor 220 for detecting an event in which a paper is wrapped in the fuser 210 in operation 410. [0055] In operation 420, the image forming apparatus 10 may obtain reference temperature information including reference temperature values of the fuser 210 and the temperature sensor 230 from the temperature sensor 230 sensing a temperature of the fuser 210 during calibration.

[0056] In operation 430, if the detection value sensed by the light sensor 220 satisfies the correction condition for correcting the light emission amount of the light sensor 220, the image forming apparatus 10 may obtain temperature information including a temperature value of the temperature sensor 230. For example, the image forming apparatus 10 may obtain a TC value and a TD value of the temperature sensor 230 at a time in which the detection value of the light sensor 220 satisfies the correction condition.

[0057] In operation 440, the image forming apparatus 10 may correct the light emission amount of the light sensor 220 based on the reference temperature information and the temperature information of the temperature sensor 230. [0058] For example, the image forming apparatus 10 may calculate an offset value of a parameter controlling the light emission amount of the light sensor 220 based on a difference between the reference temperature value and the temperature value of the temperature sensor 230. For example, the parameter may represent a parameter for controlling a duty ratio through a pulse width modulation of a light emitting element of the light sensor 220. The processor 250 may control the light emission amount of the light sensor 220 based on the offset value of the parameter.

[0059] In a case where the detection value sensed by the light sensor 220 satisfies a preset reference range according to the correction of the light emission amount of the light sensor 220, the image forming apparatus 10 may maintain a value of the parameter controlling the light emission amount of the light sensor 220.

[0060] FIG. 5 is a flowchart illustrating an operating method of an image forming apparatus to correct a light emission amount of a light sensor based on temperature information of a temperature sensor, according to an example. [0061] Referring to FIG. 5, the image forming apparatus 10 may obtain a reference difference value indicating a difference between a reference TC value and a reference TD value of the temperature sensor 230 during calibration in operation 510.

[0062] In operation 520, the image forming apparatus 10 may obtain a target difference value between a TC value and a TD value of the temperature sensor 230 at a time in which a detection value of the light sensor 220 satisfies a correction condition.

[0063] In operation 530, the image forming apparatus 10 may detect whether a difference between the target difference value and the reference difference value is greater than or equal to A. In an example, A is a constant and may be preset. In a case where the difference between the target difference value and the reference difference value is greater than or equal to A, the image forming apparatus 10 may calculate a value obtained by dividing the difference between the target difference value and the reference difference value by A as a first offset value in operation 550. In addition, based on a remainder existing as a result of dividing the difference between the target difference value and the reference difference value by A, a quotient obtained by removing the remainder from the result value may be calculated as the first offset value. For example, in a case where A is 20 and the difference between the target difference value and the reference difference value is 21 , the first offset value may be calculated as 1 . Also, in a case where the difference between the target difference value and the reference difference value is 46, the first offset value may be calculated as 2. [0064] In a case where the difference between the target difference value and the reference difference value is less than A, the image forming apparatus 10 may detect whether the detection value sensed by the light sensor 220 satisfies the correction condition, and in a case where the detection value satisfies the correction condition, obtain the temperature information of the temperature sensor 230 by returning to operation 430.

[0065] In operation 540, the image forming apparatus 10 may detect whether the difference between the TC value and the reference TC value is greater than or equal to B. In an example, B is a constant and may be preset. In a case where the difference between the TC value and the reference TC value is greater than or equal to B, the image forming apparatus 10 may calculate a value obtained by dividing the difference between the TC value and the reference TC value by B as a second offset value in operation 560. Also, based on a remainder existing in a result value as a result of dividing the difference between the TC value and the reference TC value by B, a quotient obtained by removing the remainder from the result value may be calculated as the second offset value. For example, based on B being 300 and the difference between the TC value and the reference TC value is 301 , the second offset value may be calculated as 1 . In an example where the difference between the TC value and the reference TC value is 610, the second offset value may be calculated as 2.

[0066] In a case where the difference between the TC value and the reference TC value is less than B, the image forming apparatus 10 may detect whether the detection value sensed by the light sensor 220 satisfies the correction condition, and obtain the temperature information of the temperature sensor 230 by returning to operation 430.

[0067] The image forming apparatus 10 may correct the value of the parameter by adding the first offset value and the second offset value to an existing value of the parameter for controlling the light emission amount of the light sensor 220 in operation 570. The image forming apparatus 10 may control the light emission amount of the light sensor 220 according to the corrected value of the parameter.

[0068] In operation 580, in a case where the detection value sensed by the light sensor 220 meets a preset reference range, the image forming apparatus 10 may control the light emission amount of the light sensor 220 according to the corrected value of the parameter.

[0069] FIG. 6 shows graphs respectively illustrating a TC value of a temperature sensor and a detection value of a light sensor, according to an example.

[0070] Referring to FIG. 6, a graph 610 shows a TC value 611 of the temperature sensor 230, and a graph 620 shows the detection value of the light sensor 220.

[0071] The light sensor 220 may perform calibration during an initial operation of the image forming apparatus 10. In this case, before the fuser heater 302 is heated, the light sensor 220 may perform calibration at room temperature. After calibration is performed, in a case where the fuser heater 302 heats the fuser belt 301 , as shown in a region 612 of the graph 610, the TC value 611 of the temperature sensor 230 may sharply decrease. That is, it may indicate that as the TC value 611 of the temperature sensor 230 decreases sharply, the temperature in the fuser 210 increases.

[0072] As the temperature in the fuser 210 increases, due to temperature characteristics of a light emitting element of the light sensor 220, as shown in a region 621 of the graph 620, a light emission amount of the light emitting element is reduced, so that the detection value of the light sensor 220 may also decrease. The image forming apparatus 10 may control the detection value of the light sensor 220 to be detected within a reference range as shown in a region 622 of the graph 620 by correcting the light emission amount of the light emitting element. [0073] FIG. 7 is a graph illustrating a detection value of a light sensor based on a light emission amount of the light sensor not being corrected, according to an example.

[0074] Referring to FIG. 7, the light sensor 220 may perform calibration at room temperature during an initial operation of the image forming apparatus 10. After calibration is performed, in a case where the fuser heater 302 heats the fuser belt 301 , a temperature of the fuser belt 301 may increase. As the temperature of the fuser belt 301 increases, the light emission amount of a light emitting element of the light sensor 220 may be reduced due to temperature characteristics of the light emitting element of the light sensor 220. As the amount of light emitted from the light emitting element of the light sensor 220 is reduced, a detection value sensed by the light sensor 220 may decrease.

[0075] In a case where the detection value of the light sensor 220 is detected within a preset reference range, it may be determined that the light sensor 220 is operating normally. For example, the preset reference range may be a range in which the light emitting element of the light sensor 220 irradiates a light emission amount within a certain range to the fuser belt 301 , and a light receiving element of the light sensor 220 receives a light reflected from the fuser belt 301.

[0076] Referring to FIG. 7, based on a temperature of the fuser 210 being room temperature, a TD value and a TC value measured by the temperature sensor 230 may be approximately the same. After calibration is performed, in a case where the fuser heater 302 heats the fuser belt 301 , the temperature of the fuser belt 301 may increase. In this case, the TD value and the TC value measured by the temperature sensor 230 decrease, and as the temperature of the fuser belt 301 increases, a difference between the TC value of the temperature sensor 230 and the TD value of the temperature sensor 230 may increase. In addition, as the temperature of the fuser belt 301 increases, as shown in a region 710 of the graph of FIG. 7, the detection value of the light sensor 220 may also be less than a lower limit value of a reference range.

[0077] In a case where the detection value of the light sensor 220 is less than the lower limit value of the reference range, a detection power performance of the light sensor 220 may deteriorate, so that the image forming apparatus 10 may compensate for the detection value of the light sensor 220. That is, the image forming apparatus 10 may compensate for the detection value of the light sensor 220 by increasing the reduced light emission amount of the light emitting element of the light sensor 220 as the temperature of the fuser 210 increases.

[0078] FIG. 8 is a graph illustrating a detection value of a light sensor based on a light emission amount of the light sensor being corrected, according to an example.

[0079] The image forming apparatus 10 may monitor whether the detection value of the light sensor 220 satisfies a correction condition for correcting the light emission amount of the light sensor 220. For example, the image forming apparatus 10 may monitor whether the detection value of the light sensor 220 is detected within a reference range. In a case where a temperature of the fuser 210 increases, a TD value and a TC value measured by the temperature sensor 230 may decrease, and the detection value of the light sensor 220 may be less than a lower limit value within the reference range. The image forming apparatus 10 may detect that the light emission amount of the light sensor 220 has decreased, and may correct the light emission amount of the light sensor 220 based on the TD value and the TC value of the temperature sensor 230. The image forming apparatus 10 may correct the light emission amount of the light sensor 220 as described with reference to FIGS. 2 to 5.

[0080] Referring to FIG. 8, based on the light emission amount of the light sensor 220 being corrected, the detection value of the light sensor 220 may be detected within a reference range 810.

[0081] FIG. 9 is a graph illustrating a TD value and a TC value of a temperature sensor, according to an example.

[0082] Referring to FIG. 9, based on the fuser belt 301 being heated by the fuser heater 302, a temperature of the fuser belt 301 increases, and the TC value and the TD value measured by the temperature sensor 230 decrease.

[0083] Calibration may be performed during an initial operation of the image forming apparatus 10. The temperature of the fuser 210 during the initial operation of the image forming apparatus 10 may be room temperature. In this case, referring to the region 910, the difference between the compensation value and the detection value of the temperature sensor 230 may be small. As the fuser heater 302 heats the fuser belt 301 , a temperature of the fuser 210 may increase, and the TC value of the temperature sensor 230 may abruptly decrease. In this case, referring to a region 920, the difference between the TC value and the TD value of the temperature sensor 230 may be greater than a difference between the TC value and the TD value of the temperature sensor 230 immediately after calibration is performed. The image forming apparatus 10 may detect an increase in the temperature of the fuser 210 based on the difference value between the TC value and the TD value of the temperature sensor 230.

[0084] Similarly, referring to regions 930 and 940, as the fuser heater 302 heats the fuser belt 301 , the temperature of the fuser 210 may increase. As the temperature of the fuser 210 increases, the difference between the TC value and the TD value of the temperature sensor 230 may rapidly increase. The image forming apparatus 10 may detect an amount of change in the temperature of the fuser 210 based on the difference between the TC value and the TD value of the temperature sensor 230 and correct the light emission amount of the light sensor 220.

[0085] FIG. 10 is a diagram illustrating instructions stored in a non- transitory computer-readable storage medium, according to an example.

[0086] The non-transitory computer-readable storage medium 1000 shown in FIG. 10 includes instructions for an operation method of an image forming apparatus for correcting a light emission amount of a light sensor based on a temperature sensor in a case where the detection value of the light sensor in the image forming apparatus satisfies a correction condition for correcting the light emission amount of the light sensor. Commands for an operation method of the image forming apparatus for correcting the light emission amount of the light sensor based on the temperature information may be stored. For example, the computer-readable storage medium 1000 may store instructions 1010 for performing calibration to compensate for the detection power of the light sensor for detecting an event in which a paper is wrapped in the fuser, instructions 1020 for obtaining reference temperature information including reference temperature values of the fuser and the temperature sensor from the temperature sensor for detecting the temperature of the fuser during calibration, instructions 1030 for obtaining temperature information including the temperature value of the temperature sensor in a case where the detection value sensed by the light sensor satisfies a correction condition for correcting the light emission amount of the light sensor, and instructions 1040 for correcting the light emission amount of the light sensor based on the reference temperature information and the temperature information of the temperature sensor.

[0087] Examples of an operating method of an image forming apparatus as described above may be implemented in the form of a non-transitory computer- readable storage medium that stores instructions or data executable by a computer or processor. An example operating method of an image forming apparatus as described above may be written as a program that may be executed on a computer, and may be implemented in a general-purpose digital computer that operates such a program using a computer-readable storage medium. Such computer-readable storage mediums may be any device capable of storing read only memory (ROM), random-access memory (RAM), flash memory, CD-ROMs, CD-Rs, CD+Rs, CD-RWs, CD+RWs, and DVD-ROMs., DVD-Rs, DVD+Rs, DVD- RWs, DVD+RWs, DVD-RAMs, BD-ROMs, BD-Rs, BD-R LTHs, BD-REs, magnetic tapes, floppy disks, magneto-optical data storage devices, a hard disk, a solid-state disk (SSD), machine readable instructions, associated data, data files, and data structures, and providing machine readable instructions, associated data, data files, and data structures to a computer such that the processor or the computer may execute an instruction.

[0088] It should be understood that examples described herein should be considered in a descriptive sense and not for purposes of limitation. Descriptions of features or aspects within each example should typically be considered as available for other similar features or aspects in other examples. While examples have been described with reference to the figures, it will be understood that various changes in form and details may be made therein without departing from the spirit and scope as defined by the following claims.