Patent Description:
Conventionally, in an image forming apparatus such as a printer, a facsimile machine, and a copying machine, predetermined power generated in a power supply device is supplied to a predetermined load of the image forming apparatus. The image forming apparatus includes a power-supply control device. The power-supply control device causes a shift from a normal mode to a power-saving mode, when the image forming apparatus has not operated for a predetermined time. In the power-saving mode, power consumption is smaller than power consumption in the normal mode. However, it is necessary to maintain the normal mode for a predetermined time even after completion of an operation by a user, until the shift to the power-saving mode is completed. Therefore, unnecessary power may be consumed.

A method of trying to address this issue is to provide the image forming apparatus with a human detection unit, and adjust sensitivity of the human detection unit according to a processing execution operation of the user. Another method is to adjust a count value of a timer used for a shift to the power-saving mode, according to frequency of operating a power-saving mode release unit. There is a technique that attempts to realize compatibility between user convenience and power-consumption reduction, by using those methods (<CIT>).

However, in the above-described technique discussed in <CIT>, it is still necessary to maintain the normal mode for a predetermined time until a shift to the power-saving mode is completed, even after completion of the user operation, while adjustment of sensitivity of the human detection unit and of the count value of the timer is performed. Therefore, in this technique, unnecessary power consumption still exists. <CIT> discloses a power supply control device including a power-supply-state transition control that shifts a state of operation among power states based on detection of a body capable of movement in a region.

The present invention is directed to an image forming apparatus capable of suppressing unnecessary power consumption while ensuring convenience of an operator, by switching power control to adapt to movement of the operator moving away from an operation unit.

According to a first aspect of the present invention, there is provided an image forming apparatus as specified in claims <NUM> to <NUM>. According to a second aspect of the present invention, there is provided a method performed by an image forming apparatus as specified in claims <NUM> to <NUM>.

Various exemplary embodiments, features, and aspects of the invention will be described in detail below with reference to the drawings.

<FIG> is a diagram used to describe a configuration of an image forming apparatus (an image forming apparatus <NUM>) according to a first exemplary embodiment. In the present exemplary embodiment, the image forming apparatus <NUM> includes a printer unit <NUM>, a scanner unit <NUM>, and a main controller unit <NUM>. It is to be noted that, in the present exemplary embodiment, the image forming apparatus <NUM> that operates in a first power state and a second power state will be described as an example. In the second power state, power consumption is smaller than power consumption in the first power state.

In <FIG>, the printer unit <NUM> performs processing for forming an image on a sheet-like recording medium (a sheet of paper) according to an electrophotographic method, for example. The scanner unit <NUM> optically reads an image from a document, and converts the read image to a digital image.

The main controller unit <NUM> controls the entire image forming apparatus <NUM>, and performs control for image processing and a copying operation. The printer unit <NUM> performs the image processing on the image of the document read by the scanner unit <NUM>. Further, the main controller unit <NUM> is connected to a personal computer (PC) <NUM> through a network <NUM>. The network <NUM> is a network such as a local area network (LAN), and may be either wired or wireless. The PC <NUM> is a general computer apparatus including a central processing unit (CPU), a random-access memory (RAM), and a fixed storage device such as a hard disk drive (HDD). A monitor, a keyboard, a mouse, and the like are connected to the PC <NUM>. The PC <NUM> is installed with a printer driver program serving as an image forming program.

When executing the printer driver program, the PC <NUM> generates page-description language (PDL) data according to a rendering command issued by an operating system or an application program, and transmits the generated PDL data to the image forming apparatus <NUM>. Here, the PDL data is based on a PDL that can be processed by the image forming apparatus <NUM>. The PDL data results from conversion by the printer driver program. The image forming apparatus <NUM> performs a printing operation. In the printing operation, a bitmapped image is generated based on the PDL data received from the PC <NUM>, and the generated bitmapped image is formed on a sheet.

The image forming apparatus <NUM> includes an alternating current (AC) plug <NUM>. When the AC plug <NUM> is inserted into an outlet provided outside the image forming apparatus <NUM>, the image forming apparatus <NUM> receives power from an AC commercial power source.

Further, the image forming apparatus <NUM> includes a human detection sensor unit <NUM> that detects a moving object, such as a human, around the image forming apparatus <NUM>. It is to be noted that the human detection sensor unit <NUM> is not limited in particular, as far as the human detection sensor unit <NUM> is a sensor capable of determining the presence or absence of a human in a detection region. Examples of the human detection sensor unit <NUM> include a pyroelectric sensor and a reflection-type sensor. The pyroelectric sensor senses infrared rays emitted from a human, and determines the presence or absence of the human based on a variation in the infrared rays. The reflection-type sensor emits light such as infrared rays, and detects reflected light of the emitted light. The human detection sensor unit <NUM> may be a sensor including a plurality of receiving units that receive infrared rays. The plurality of receiving units may be arranged in a grid, or may be linearly arranged.

<FIG> are conceptual diagrams each illustrating a detection region of the human detection sensor unit <NUM> illustrated in <FIG>.

In <FIG>, a detection region <NUM> is a detection region of the human detection sensor unit <NUM>. The human detection sensor unit <NUM> detects a human when the human is in the detection region <NUM>. <FIG> illustrates a concept when the image forming apparatus <NUM> is viewed from a side. The detection region <NUM> of the human detection sensor unit <NUM> is directed downwards from the image forming apparatus <NUM> in front of which a user is expected to be present to perform an operation while standing.

Further, <FIG> illustrates a concept when the image forming apparatus <NUM> is viewed from above. The human detection sensor unit <NUM> is attached to a front face of an operation unit <NUM>, because a human is expected to stand in front of the image forming apparatus <NUM> and to operate the operation unit while facing this front face. It is to be noted that this detection region <NUM> can be modified according to factors such as an attachment location of the human detection sensor unit <NUM> and an orientation at the time of attachment.

<FIG> is a block diagram illustrating a configuration of each of the main controller unit <NUM> illustrated in <FIG> and a power supply device <NUM>.

In <FIG>, the main controller unit <NUM> includes a power-supply control unit <NUM>, a network processing unit <NUM>, a timer unit <NUM>, a memory unit <NUM>, an HDD unit <NUM>, a CPU unit <NUM>, and an image processing unit <NUM>.

The power-supply control unit <NUM> performs switching control for supplying/shutting-off power to each processing unit of the image forming apparatus <NUM>, according to a control program executed by the CPU unit <NUM> of the main controller unit <NUM>. The switching control also depends on the state of each of the human detection sensor unit <NUM>, an operation unit <NUM>, and the network processing unit <NUM>. The network processing unit <NUM> is connected to the CPU unit <NUM> and the power-supply control unit <NUM>. The power-supply control unit <NUM> is supplied with power, even after the state of the processing unit including the CPU unit <NUM> shifts to a power-saving state. In this power-saving state, the power-supply control unit <NUM> performs the switching control for supplying/shutting-off the power to each processing unit of the image forming apparatus <NUM>. Therefore, the power-supply control unit <NUM> may be configured to include a sub CPU.

The network processing unit <NUM> functions as a control unit that outputs, to the CPU unit <NUM>, the PDL data transmitted from the PC <NUM> through the network <NUM>. Further, when the image forming apparatus <NUM> is in a power-saving mode, the network processing unit <NUM> instructs the power-supply control unit <NUM> to shift to a normal mode, upon receipt of a network packet directed to the image forming apparatus <NUM> from the network <NUM>.

The human detection sensor unit <NUM> is connected to the power-supply control unit <NUM>, and notifies the power-supply control unit <NUM> of the presence or absence of a human in the detection region of the human detection sensor unit <NUM>. Further, when the image forming apparatus <NUM> is in the power-saving mode, the human detection sensor unit <NUM> instructs the power-supply control unit <NUM> to shift to the normal mode, upon detecting the presence of a human in the detection region of the human detection sensor unit <NUM>.

The timer unit <NUM> is connected to the CPU unit <NUM>, and performs processing for clocking a shift time for a shift of the image forming apparatus <NUM> to the power-saving mode. The memory unit <NUM> is connected to the CPU unit <NUM>. The memory unit <NUM> is a volatile memory such as a double data rate synchronous dynamic random-access memory (DDR SDRAM). The memory unit <NUM> is a main memory that stores data such as user data created by, for example, the control program executed by the CPU unit <NUM>.

Further, the memory unit <NUM> stores operation history information <NUM> that indicates when the operation unit <NUM> was operated. The operation history information <NUM> is updated by the CPU unit <NUM>, every time the operation unit <NUM> is operated. The HDD unit <NUM> is connected to the CPU unit <NUM>. The HDD unit <NUM> is a storage device that temporarily stores the program executed by the CPU unit <NUM> and the PDL data transmitted from the network <NUM>.

The HDD unit <NUM> stores processing execution history information <NUM>. The processing execution history information <NUM> indicates when a job such as a copying operation, a printing operation, and a scanning operation was executed. The processing execution history information <NUM> is updated by the CPU unit <NUM>, every time the job is completed.

The CPU unit <NUM> controls the entire image forming apparatus <NUM>. The CPU unit <NUM> implements a function such as a copy function and a print function, based on a control program stored in the HDD unit <NUM>. The image processing unit <NUM> is connected to the CPU unit <NUM>, the printer unit <NUM>, and the scanner unit <NUM>. The image processing unit <NUM> performs image processing such as color space conversion on a digital image output from the scanner unit <NUM>, and outputs data, as to which the image processing was performed, to the CPU unit <NUM>.

The image processing unit <NUM> performs image processing such as color space conversion on image data read by the scanner unit <NUM> or image data generated based on the PDL data received from the PC <NUM>. The image processing unit <NUM> then converts the image data into bitmap data, and outputs the bitmap data to the printer unit <NUM>. The operation unit <NUM> is connected to the power-supply control unit <NUM> and the CPU unit <NUM>. The operation unit <NUM> includes an operation liquid crystal panel and hard keys including a power-saving mode release button, to accept instructions input by a user. Further, upon detecting a press of the power-saving mode release button when the image forming apparatus <NUM> is in the power-saving mode, the operation unit <NUM> instructs the power-supply control unit <NUM> to perform a shift to the normal mode.

The power supply device <NUM> of the image forming apparatus <NUM> illustrated in <FIG> will be described with reference to <FIG>.

When the AC plug <NUM> of the image forming apparatus <NUM> is inserted into an outlet provided outside the image forming apparatus <NUM>, a relay <NUM> and a first-controller power-supply-system power supply unit <NUM> are supplied with power from the AC commercial power source. The relay <NUM> is controlled by the power-supply control unit <NUM>. Turning on the relay <NUM> enables power supply to a high-voltage power supply unit <NUM> and a low-voltage power supply unit <NUM>. The first-controller power-supply-system power supply unit <NUM> is controlled by the power-supply control unit <NUM>, and connected to a first power supply system <NUM> of the main controller unit <NUM>.

The first power supply system <NUM> is continuously supplied with power even in the power-saving mode. The human detection sensor unit <NUM>, the power-supply control unit <NUM>, the network processing unit <NUM>, the timer unit <NUM>, and the memory unit <NUM> are connected to the first power supply system <NUM>. A power supply unit <NUM> including the high-voltage power supply unit <NUM> and the low-voltage power supply unit <NUM> is controlled by the power-supply control unit <NUM>. Power supply to the power supply unit <NUM> is shut off in the power-saving mode. The high-voltage power supply unit <NUM> is mainly used for, for example, motor driving for the printer unit <NUM> and the scanner unit <NUM>, as well as a heater of a fixing unit. The low-voltage power supply unit <NUM> supplies power to the printer unit <NUM>, the scanner unit <NUM>, and a second power supply system <NUM> of the main controller unit <NUM>. Power supply to the second power supply system <NUM> of the main controller unit <NUM> is shut off in the power-saving mode. The HDD unit <NUM>, the CPU unit <NUM>, the image processing unit <NUM>, and the operation unit <NUM> are connected to the second power supply system <NUM>.

A power supply unit <NUM> includes, a scanner-unit power supply unit <NUM>, a printer-unit power supply unit <NUM>, and a second-controller power-supply-system power supply unit <NUM>. The power supply unit <NUM> is controlled by the power-supply control unit <NUM>, and power supply to the power supply unit <NUM> is shut off in the power-saving mode. The scanner-unit power supply unit <NUM> is connected to the scanner unit <NUM>, and receives power from the high-voltage power supply unit <NUM> and the low-voltage power supply unit <NUM>. The scanner-unit power supply unit <NUM> is controlled to be ON/OFF by the power-supply control unit <NUM>.

The printer-unit power supply unit <NUM> is connected to the printer unit <NUM>, and receives power from the high-voltage power supply unit <NUM> and the low-voltage power supply unit <NUM>. The printer-unit power supply unit <NUM> is controlled to be ON/OFF by the power-supply control unit <NUM>. The second-controller power-supply-system power supply unit <NUM> is connected to the second power supply system <NUM> of the main controller unit <NUM>, and receives power from the low-voltage power supply unit <NUM>. The second-controller power-supply-system power supply unit <NUM> is controlled to be ON/OFF by the power-supply control unit <NUM>.

<FIG> is a block diagram used to describe a power supply state of the image forming apparatus <NUM> according to the present exemplary embodiment. In <FIG>, a grayed part corresponds to a power supply state in the power-saving mode. It is to be noted that, in the normal mode, power is supplied to all blocks as illustrated in <FIG>. In this state, only a necessary function may be supplied with power, which, however, will not be described here. In the power-saving mode, some of the blocks are supplied with power as illustrated in <FIG>.

First, the first-controller power-supply-system power supply unit <NUM> is supplied with power from the AC commercial power source, through the AC plug <NUM>. The first-controller power-supply-system power supply unit <NUM> supplies power to blocks including the human detection sensor unit <NUM>, the power-supply control unit <NUM>, the network processing unit <NUM>, the timer unit <NUM>, and the memory unit <NUM>. It is to be noted that, although power supply to the operation unit <NUM> is illustrated to be shut off, the power-supply control unit <NUM> is allowed to detect a press of the power-saving mode release button.

Next, a sequence of a shift from the normal mode to the power-saving mode will be described.

When a power-saving mode shift condition is satisfied, the CPU unit <NUM> executes power-saving mode shift processing. The power-saving mode shift condition is, for example, such a condition that any operation with regard to the image forming apparatus <NUM> has not been performed for a predetermined time. In the power-saving mode shift processing, at first, the CPU unit <NUM> executes the power-saving mode shift processing for software, such as saving of data of the image processing unit <NUM>, according to the control program stored in the HDD unit <NUM>.

Upon completion of the power-saving mode shift processing for the software, the CPU unit <NUM> instructs the power-supply control unit <NUM> to shut off power supply to the relay <NUM>, the power supply unit <NUM>, and the power supply unit <NUM>. Upon receipt of a power shut-off instruction from the CPU unit <NUM>, the power-supply control unit <NUM> shuts off the power supply to the relay <NUM>, the power supply unit <NUM>, and the power supply unit <NUM>, thereby completing a shift to the power-saving mode in which power consumption is small.

<FIG> is a flowchart used to describe a method for controlling the image forming apparatus <NUM> according to the present exemplary embodiment. This is an example of a power-saving mode return (shift) sequence. It is to be noted that a non-illustrated sub CPU of the power-supply control unit <NUM> implements each step by loading a control program into a memory and executing the loaded control program. Control of timing for a shift to the normal mode in the present exemplary embodiment will be described below.

First, in step S701, the power-supply control unit <NUM> checks the state of each of the network processing unit <NUM>, the human detection sensor unit <NUM>, and the power-saving mode release button of the operation unit <NUM>, to determine whether there is an instruction for a shift from the power-saving mode to the normal mode. Upon determining that there is no instruction for a shift to the normal mode (No in step S701), the power-supply control unit <NUM> regularly polls each unit to check the state thereof, until an instruction for a shift to the normal mode occurs. Upon determining that there is an instruction for a shift to the normal mode (YES in step S701), in step S702, the power-supply control unit <NUM> turns on the relay <NUM>, the power supply unit <NUM>, and the power supply unit <NUM>, to start power supply to each of these units.

When power is supplied to the CPU unit <NUM>, in step S703, the CPU unit <NUM> executes power-saving mode return processing. In the power-saving mode return processing, the CPU unit <NUM> executes the power-saving mode return processing for software such as restoration of data in the image processing unit <NUM>, according to the control program stored in the HDD unit <NUM> or the memory unit <NUM>.

In step S704, upon completion of the power-saving mode return processing, the CPU unit <NUM> accesses the power-supply control unit <NUM> to check a factor of the shift to the normal mode. When the factor of the shift to the normal mode is determined not to be a return due to a job (NO in step S704), the power-supply control unit <NUM> maintains the normal mode. In step S705, when the power-supply control unit <NUM> determines that the factor of the shift to the normal mode is a return due to a job such as a printing operation and a copying operation (YES in step S704), the CPU unit <NUM> executes the job. In step S706, upon completion of the job, the CPU unit <NUM> updates the processing execution history information <NUM> stored in the HDD unit <NUM>, which completes the processing.

<FIG> is a flowchart used to describe the method for controlling the image forming apparatus <NUM> according to an exemplary embodiment not covered by the claimed invention. This is an example of a power-saving mode return (shift) sequence. It is to be noted that a non-illustrated sub CPU of the power-supply control unit <NUM> implements each step by loading the control program into the memory and executing the loaded control program. The state of power supply to all processing units is switched to the power-saving state, based on an operation state brought by an operation unit <NUM> and a job execution state brought by a processing unit. Control of such switching will be described below. In step S501, when the image forming apparatus <NUM> is in the normal mode after returning from the power-saving mode, the CPU unit <NUM> checks the state of the human detection sensor unit <NUM> through the power-supply control unit <NUM> to determine whether a human is present in front of the image forming apparatus <NUM>.

Upon determining that a human is present in front of the image forming apparatus <NUM> (YES in step S501), the CPU unit <NUM> regularly polls the human detection sensor unit <NUM> until the human detection sensor unit <NUM> enters a state of not detecting a human. In step S502, upon determining that no human is present in front of the image forming apparatus <NUM> (NO in step S501), the CPU unit <NUM> checks the processing execution history information <NUM> stored in the HDD unit <NUM>. When there is no job execution history in the processing execution history information <NUM> after the return from the power-saving mode (NO in step S502), the CPU unit <NUM> determines that the human is temporarily away from the image forming apparatus <NUM> (the image forming apparatus <NUM> is in use).

Accordingly, in step S503, the CPU unit <NUM> resets the timer <NUM> and sets it at the time to be measured so as to measure a predetermined time. Then the CPU unit <NUM> starts measurement of the predetermined time by activating the timer unit <NUM>. In step S504, after activating the timer unit <NUM>, the CPU unit <NUM> checks the state of the human detection sensor unit <NUM> through the power-supply control unit <NUM> to determine whether a human is present in front of the image forming apparatus <NUM> (or the human comes back). Upon determining that a human is present in front of the image forming apparatus <NUM> (YES in step S504), in step S506, the CPU unit <NUM> resets the timer unit <NUM> to cancel the measurement of the predetermined time, and then returns to step S501.

After resetting the timer unit <NUM>, the CPU unit <NUM> regularly polls the human detection sensor unit <NUM>, until the human detection sensor unit <NUM> enters a state of not detecting a human. Upon determining that there is no human in front of the image forming apparatus <NUM> (NO in step S504), in step S505, the CPU unit <NUM> checks a timer count value of the timer unit <NUM>. When the predetermined time has not elapsed (NO in step S505), the CPU unit <NUM> checks the state of the human detection sensor unit <NUM> again.

When the predetermined time has elapsed (YES in step S505), in step S507, the CPU unit <NUM> executes the power-saving mode shift processing to cause a shift to the power-saving mode in which power consumption is small. Likewise, when there is a job execution history in the processing execution history information <NUM> after the return from the power-saving mode (YES in step S502), in step S507, the CPU unit <NUM> executes the power-saving mode shift processing to cause a shift to the power-saving mode. Then, the processing ends.

As described above, according to the present exemplary embodiment, when a human detection sensor unit <NUM> detects a departure of a user after execution of a job such as copying, a shift to the power-saving mode immediately occurs. Therefore, unnecessary power consumption can be suppressed as much as possible. In addition, when a departure of the user in a state in which the job has not been executed is detected, the normal mode is maintained for a predetermined time. Therefore, convenience of the user can be maintained.

According a second exemplary embodiment, a power-saving mode return (shift) sequence when any operation on an operation unit <NUM> after a return from the power-saving mode is detected will be described. It is to be noted that a configuration of an image forming apparatus <NUM> of the present exemplary embodiment is similar to the configuration in the first exemplary embodiment and therefore will not be described.

<FIG> is a flowchart used to describe the method for controlling the image forming apparatus <NUM> according to the present exemplary embodiment and corresponding to the claimed invention. This is an example of the power-saving mode return (shift) sequence. It is to be noted that a non-illustrated sub CPU of the power-supply control unit <NUM> implements each step by loading the control program into the memory and executing the loaded control program.

In step S601, when the image forming apparatus <NUM> is in the normal mode after returning from the power-saving mode, the CPU unit <NUM> checks the state of the human detection sensor unit <NUM> through the power-supply control unit <NUM> to determine whether a human is present in front of the image forming apparatus <NUM>. Upon determining that a human is present in front of the image forming apparatus <NUM> (YES in step S601), the CPU unit <NUM> regularly polls the human detection sensor unit <NUM>, until the human detection sensor unit <NUM> enters a state of not detecting a human. In step S602, upon determining that no human is present in front of the image forming apparatus <NUM> (NO in step S601), the CPU unit <NUM> checks the processing execution history information <NUM> stored in the HDD unit <NUM>. When there is no job execution history in the processing execution history information <NUM> after the return from the power-saving mode (NO in step S602), in step S603, the CPU unit <NUM> checks the operation history information <NUM> stored in the memory unit <NUM>.

When there is an operation history in the operation history information <NUM> after the return from the power-saving mode (YES in step S603), the CPU unit <NUM> determines that the human is temporarily away from the image forming apparatus <NUM> (the image forming apparatus <NUM> is in use). Then, in step S604, the CPU unit <NUM> starts measurement of a predetermined time by activating the timer unit <NUM>, after resetting the timer unit <NUM> and then setting the timer unit <NUM> at the time to be measured , so as to measure the predetermined time. In step S605, after activating the timer unit <NUM>, the CPU unit <NUM> checks the state of the human detection sensor unit <NUM> through the power-supply control unit <NUM> to determine whether a human is present in front of the image forming apparatus <NUM> (or the human comes back).

In step S607, upon determining that the human is present in front of the image forming apparatus <NUM> (YES in step S605), the CPU unit <NUM> resets the timer unit <NUM> to cancel the measurement of the predetermined time. After resetting the timer unit <NUM>, the CPU unit <NUM> regularly polls the human detection sensor unit <NUM>, until the human detection sensor unit <NUM> enters a state of not detecting the human.

Upon determining that there is no human in front of the image forming apparatus <NUM> (NO in step S605), in step S606, the CPU unit <NUM> checks a timer count value of the timer unit <NUM>. When the predetermined time has not elapsed (NO in step S606), the CPU unit <NUM> checks the state of the human detection sensor unit <NUM> again. When the predetermined time has elapsed (YES in step S606), in step S608, the CPU unit <NUM> executes the power-saving mode shift processing, to cause a shift to the power-saving mode in which power consumption is small.

Likewise, when there is a job execution history in the processing execution history information <NUM> after the return from the power-saving mode (YES in step S602), in step S608, the CPU unit <NUM> also executes the power-saving mode shift processing to cause a shift to the power-saving mode. Further, when there is no operation history in the operation history information <NUM> after the return from the power-saving mode (NO in step S603), the CPU unit <NUM> executes the power-saving mode shift processing as well to cause a shift to the power-saving mode.

As described above, according to the present exemplary embodiment, upon detection of a departure of a user in a state in which neither operation of the operation unit <NUM> nor execution of a job has been performed, a shift to the power-saving mode occurs immediately. Therefore, unnecessary power consumption can be suppressed as much as possible. In addition, when the human detection sensor unit <NUM> detects a departure of a user in a state in which the operation unit <NUM> has been operated but a job has not been executed, the normal mode is maintained for a predetermined time. Therefore, convenience of the user can be preserved.

Each step of the present embodiments can also be realized by executing software (a program) obtained through a network or any of various storage mediums in a processing device (a CPU, or a processor) such as a PC (a computer).

Claim 1:
An image forming apparatus (<NUM>) configured to operate in a first power state and a second power state in which power consumption is smaller than power consumption in the first power state, the image forming apparatus comprising:
a detection means (<NUM>) configured to detect an object present in front of the image forming apparatus;
an operation means (<NUM>) configured to accept an operation; and
a power-supply control means (<NUM>) configured to shift a state of the image forming apparatus from the second power state to the first power state, on a basis that the detection means (<NUM>) detects an object present in front of the image forming apparatus,
characterised in that upon determining that no object is present in front of the image forming apparatus (<NUM>), the power-supply control means (<NUM>) is configured to shift the state of the image forming apparatus from the first power state to the second power state in response to a lapse of a predetermined time in a state in which no object has been detected by the detection means (S606, YES) in a case where a job has not been executed and the operation means (<NUM>) has been operated (S601 to S603, S604 to S606), and
wherein upon determining that no object is present in front of the image forming apparatus (<NUM>) (S601, NO), the power-supply control means (<NUM>) is configured to shift the state of the image forming apparatus from the first power state to the second power state immediately in a case where the job has not been executed and the operation means (<NUM>) has not been operated.