KR20200112003A - Auto-focus driving method for preventing oscillation due to shock and device for the same - Google Patents

Abstract

Disclosed is a driving device control method comprising the following steps of: determining a new target position value according to a new lens position change command when the new lens position change command is input, and reducing a phase margin between an error value and a current position value; providing the determined new target position value to an error detection part; and increasing the phase margin between the error value and the current position value after a predetermined time.

Description

AF driving method for preventing oscillation due to shock and device for the same {Auto-focus driving method for preventing oscillation due to shock and device for the same}

The present invention relates to a method for driving autofocus of an AF module.

1 shows a structure according to an embodiment of an autofocus (AF) camera module device 50 including an actuator. When the target position value PT is input to the camera module device 50, the AF driver 150 adjusts the output current to move the lens 220 to a desired position to perform a desired operation.

The most widely used actuator for moving the AF module (imaging device) 20 or the image sensor is a voice coil motor (VCM, hereinafter referred to as VCM). The VCM moves the lens module to a desired position by installing a coil on the outside of the camera lens module and adjusting the direction and amount of current flowing through the coil.

In order to control the VCM, a proportional/integral/derivative (PID: Proportional / Integral / Derivative) control unit may be used.

The PID controller determines how optimized the ratio of the three coefficients: proportional coefficient (Kp) (= proportional gain), integral coefficient (Ki) (= integral gain), and differential coefficient (Kd) (= differential gain) Accordingly, a change in performance occurs. The proportional coefficient Kp is related to the current control value, the integral coefficient Ki is related to the past control value, and the differential coefficient Kd is related to the future control value. The proportional coefficient (Kp) is related to how many times the weight is given to the current error, and the integral coefficient (Ki) is related to the number of errors in the past and controlled based on the current standard, and the differential coefficient (Kd ) Is related to how much value and direction in the future to control the error. Since one of these three PID coefficients has a close influence on the other two coefficients, a different PID coefficient may be determined as an optimal value depending on the environment even in the same PID control configuration. The PID control unit can change these three coefficients in real time. Since these three coefficients are optimized for a given environment and can have various values depending on the purpose, it is difficult to satisfy all conditions with one set value.

The target position value PT is, for example, a number from 0 to 1023 in the case of a 10-bit digital input system, and this number represents the target position of the lens.

The target position value PT indicates the position of the lens 220 desired by the user, and the AF module 20 is driven according to the target position value PT to change the position of the lens 220.

The value of the position of the lens 220 may be collected as an analog value by the Hall sensor 110, and this analog value is converted to a digital output value through the ADC 130 and is at the same level as the target position value PT. Is converted to

The digital output value may be a current position value (PC) of the lands 220 or a value related thereto.

That is, if the current position value PC fed back is equal to the target position value PT, the lens 220 is in a desired position and the camera module device 50 is in an equilibrium state.

The current position value PC that is fed back may also have the same range as the target position value PT, for example, 0 to 1023.

2 shows a change in the position of a lens according to a general driving method. When the user gives a change command through the input position command, the lens follows from the current position to the target position value PT according to the operation of the AF system.

However, after the camera module device 50 is stabilized, when a disturbance (shock) occurs, the lens 220 moves and the position of the moved lens 220 is provided as a feedback signal. As a result, the error value shown in FIG. err) is incremented. In this case, when the margin of the camera module device 50 is insufficient, a problem occurs that the camera module device 50 causes oscillation.

As related technologies, patent applications of Publication No. KR 10-2015-0061399 and Publication No. KR 10-2015-0072036 have been disclosed.

In the above publication number KR 10-2015-0061399, in an optical image stabilization device, the output of the Hall sensor is not provided to the PID control unit when a low-frequency hand shake is detected. The technology to provide is public

According to the publication number KR 10-2015-0072036, in the optical image stabilization device, according to the value of the image stabilization frequency A technology that differentiates and applies PID coefficients for low and high frequencies has been disclosed. Specifically, a PID coefficient selection and switching control unit that applies a PID coefficient suitable for the determined shake frequency to the PID control unit is disclosed. In addition, a technology for selectively applying PID coefficients for low frequency and PID coefficients for high frequency is disclosed based on a result of comparing the image-shake frequency and the reference frequency (eg, 3 Hz) for the PID coefficient selection and switching control unit. In addition, a technique has been disclosed in which the application of new PID coefficients is performed when one ongoing PID control is completed.

However, even with the above-described prior art, the problem of causing the camera module device 50 to oscillate due to the above-described disturbance (shock) cannot be solved.

Cameras mounted on mobile phones are exposed to various user environments. When an impact is applied to the camera, an oscillation phenomenon may occur and the camera may malfunction. An object of the present invention is to provide a technique for suppressing oscillation of a camera module device due to an impact.

In order to help understand the solution of the present invention, it is necessary to first understand the small signal model of the camera module device 50 through FIG. 3.

3 shows a small signal model of a camera module device according to an embodiment of the present invention.

PID(s) is the transfer function of the PID block 142.

F(s) is a transfer function of the actuator driving stage 150.

M(s) is a transfer function of the AF module 20.

H(s) is a transfer function of an amplifying circuit including the ADC 130, for example, a part that transfers the Hall voltage indicating the position of the lens. The part that transmits the Hall voltage may be, for example, the sensor unit 100 of FIG. 6.

At this time, the entire loop transfer function of the signal transmission system in which the input of the PID block 142 is used as an input signal and the output of the amplifying circuit is an output signal is expressed as a Laplace conversion function as in Equations 1 and 2.

[Equation 1]

HT(s)=PID(s)*D(s)*M(s)*H(s)

[Equation 2]

PID(s)=(P + D*s + I/s)

However, P: proportional gain, D: differential gain, I: integral gain

In Equation 2, P, I, and D are variables that can be adjusted by the user. That is, P, I, and D are parameters that can be changed by the driving device 10 included in the camera module device 50, respectively.

In FIG. 3, the transfer function βA(S) can be expressed as βA(S)=F(S)/I(S), which represents the overall loop function.

In general, in a system with feedback, oscillation occurs more as the difference between the phase of the input signal and the phase of the feedback signal approaches 180 degrees when the input signal and the feedback signal have the same magnitude. In FIG. 1, the feedback signal is a current position value (PC), and the input signal is an error value (err).

4 is a graph showing the frequency magnitude response and the frequency phase response of the transfer function βA(S).

At a frequency in which the magnitude of the feedback signal is the same as the magnitude of the input signal, a difference between the phase of the feedback signal and the phase of the input signal may be referred to as a phase margin.

In addition, at a frequency in which the phase of the feedback signal is the same as the phase of the input signal, a difference between the magnitude of the feedback signal and the magnitude of the input signal may be referred to as a gain margin.

If the difference between the phase margin and the gain margin is increased, the corresponding signal transmission system can be said to be stable to oscillation.

In FIG. 4, when the DC gain is lowered, the phase margin (PM) increases, thereby stabilizing the system. In other words, if the phase margin is increased under conditions in which disturbance occurs, the system is stabilized.

As a method of lowering the DC gain, that is, increasing the phase margin, a method of reducing at least one of the proportional gain (P) and the integral gain (I) of Equation 2 may be used.

According to an aspect of the present invention, it is possible to prevent the oscillation from occurring by controlling related variables inside the driving device 10 included in the camera module device 50. The driving device may be provided in the form of an IC.

According to an aspect of the present invention, during a predetermined time period in which a change in the position of the lens occurs in response to a command to change the target position value of the lens, the PID coefficient (ie, driving) allows the AF module 20 to have a fast operation characteristic. PID coefficients) can be applied. That is, the PID coefficients of the PID block 11 can be set as the driving PID coefficients. In addition, PID coefficients (ie, oscillation PID coefficients) that have a high phase margin or a slow motion characteristic can be applied during a time period in which there is no command for changing the target position value of the lens. That is, the PID coefficients of the PID block 142 may be set as the oscillation PID coefficients.

According to an aspect of the present invention, a sensor unit 100 for outputting (as a feedback signal) a current position value (PC) of the lens 220; An error detection unit 141 for generating an error value err by comparing the target position value PT determined according to the input lens position change command with the current position value; A PID controller 142 generating a driving current control value based on the error value; And a driving unit 150 for outputting a current for driving the lens based on the driving current control value, comprising: a driving device control method for controlling an operating characteristic of the driving device. can do. In the driving device control method, the driving device determines a new target position value according to the new lens position change command when a new lens position change command is input, and uses a signal input to the PID control unit as an input signal, and the sensor A first setting changing step of changing a setting of the driving device to reduce a phase margin of a signal transmission system using an additionally output signal as an output signal; Providing, by the driving device, the determined new target position value to the error detection unit; And a second setting changing step of changing, by the driving device, a setting of the driving device so that the phase margin of the signal transmission system increases after a predetermined time.

In this case, the first setting changing step includes changing the PID coefficients of the PID control unit into a predetermined driving PID coefficient, and the second setting changing step includes changing the PID coefficients of the PID control unit to a predetermined oscillation PID coefficient. And changing to, and the second proportional gain value P2 according to the oscillation PID coefficient may have a value smaller than the first proportional gain value P1 according to the driving PID coefficient.

In addition, the second integral gain value I2 according to the oscillation PID coefficient may have a value smaller than the first integral gain value I1 according to the driving PID coefficient. In this case, the second proportional gain value P2 according to the oscillation PID coefficient may have a value smaller than the first proportional gain value P1 according to the driving PID coefficient.

In this case, the new lens position change command may be provided from a host outside the driving device.

A driving apparatus according to an aspect of the present invention includes a sensor unit for outputting (as a feedback signal) a current position value of a lens; An error detection unit for generating an error value by comparing the target position value determined according to the input lens position change command and the current position value; A PID control unit that generates a driving current control value based on the error value; And a driving unit that outputs a current for driving the lens based on the driving current control value. When a new lens position change command is input, the driving device determines a new target position value according to the new lens position change command, uses a signal input to the PID control unit as an input signal, and outputs a signal output by the sensor unit. A first setting changing step of changing a setting of the driving device such that a phase margin of a signal transmission system as a signal is reduced; Providing the determined new target position value to the error detection unit; And a second setting changing step of changing the setting of the driving device so that the phase margin of the signal transmission system increases after a predetermined time.

In this case, the first setting changing step includes changing the PID coefficients of the PID control unit into a predetermined driving PID coefficient, and the second setting changing step includes changing the PID coefficients of the PID control unit to a predetermined oscillation PID coefficient. A step of changing to, wherein the second integral gain value I2 according to the oscillation PID coefficient has a value smaller than the first integral gain value I1 according to the driving PID coefficient, and a second integral gain value I1 according to the oscillation PID coefficient The 2 proportional gain value P2 may be characterized in that it has a value smaller than the first proportional gain value P1 according to the driving PID coefficient.

A camera module device according to an aspect of the present invention, comprising: the driving device described above; And

It may include; an imaging device 20 including the lens.

A user device according to an aspect of the present invention, comprising: the camera module device; A host 30 providing the lens position change command; And a user interface 40 for providing a user input to the host.

According to the present invention, in the AF camera module device, it is possible to provide a technique for suppressing oscillation caused by an impact.

1 shows a structure according to an embodiment of an AF camera module device including an actuator.
2 shows a change in the position of a lens according to a general driving method.
3 shows a small signal model of a camera module device according to an embodiment of the present invention.
4 is a graph showing the frequency magnitude response and the frequency phase response of the transfer function βA(S).
5 illustrates an AF camera module device according to an embodiment.
6 is a block diagram of an AF camera module device according to an embodiment of the present invention.
7 is a graph for explaining a driving period and a disturbance detection period defined according to an embodiment of the present invention.
8 is a flow chart showing a method of controlling a driving device provided according to an embodiment of the present invention.
9 shows the structure of a user device provided according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described in the present specification and may be implemented in various different forms. The terms used in the present specification are intended to aid understanding of the embodiments, and are not intended to limit the scope of the present invention. In addition, the singular forms used below also include plural forms unless the phrases clearly indicate the opposite meaning.

5 illustrates an AF camera module device according to an embodiment.

The housing 21 includes a lens barrel 22 including a lens 220 and a magnet 23, a ball 24 to facilitate movement of the lens 220, and a coil 240. Can include. The lens 220 is configured to automatically focus as the lens moves up and down.

When moving the lens 220 to the target position, the lens 220 may be moved to the target position by using a feedback control method of VCM. In this case, for the feedback control, the Hall sensor 110 may detect and output a current position value related to the current position of the lens 220. Then, the VCM is feedback-controlled until the detected current position value becomes the same as the target position.

The target position may be defined on the y-axis, which is the optical axis of the lens 220, and may have a value between the macro position MAC (y=0) and the infinity position INF (y=1023). At this time, in order for the feedback control to be successful, the current position value 131 output from the Hall sensor when the lens 220 is present at the y=n position (n=0, ..., 1023) must correspond to the n. do. Hereinafter, for convenience of description of the present specification, an example in which the position of the lens has an integer value of 0 to 1023 is presented.

6 is a block diagram of an AF camera module device according to an embodiment of the present invention.

The VCM driving apparatus 10 according to an embodiment of the present invention includes a hall sensor 110, an amplifier 120, an ADC 130, a control unit 140, and a driver 150. ), a Hall sensor bias voltage driver 160, a host clock input terminal 171, a host data input terminal 172, and a driving current output terminal 173.

The VCM driving device 10 may be referred to as a driving device 10. When a VCM (Voice Coil Motor) is used as a device for driving the imaging device 20, the driving device may be referred to as a VCM driving device. The present invention can be applied even when using a motor of. Accordingly, the present invention is not limited to the driving device 10 as a VCM driving device. In this patent application specification, as a preferred embodiment, a case where the driving device 10 is a VCM driving device will be described.

The VCM driving device 10 includes a lens 220, an image sensor 230 for receiving light incident through the lens 220, and a VCM 210 for adjusting a focal length of the lens 220. You can control the operation of (20). In addition, the VCM driving device 10 may detect the position of the lens 220 using the Hall sensor 110.

A magnet 250 and a coil 240 may be installed in the imaging device 20. The magnet 250 may be fixed to and disposed on the lens 220. When the driving current I is provided to the coil 240, the position of the lens 220 may be changed by the electromagnetic force formed between the magnet 250 and the coil 240.

The Hall sensor 110 included in the VCM driving device 10 may detect the magnetic force of the magnet 250 disposed on the lens 220 and output a voltage value VO regarding the position of the lens 220. A bias voltage VB for the operation of the Hall sensor 110 may be provided to the Hall sensor 110. The bias voltage VB may be provided by the Hall sensor bias voltage driver 160. The bias voltage VB provided by the Hall sensor bias voltage driver 160 may be controlled by the controller 140.

The Hall sensor 110 may be designed to output a voltage value related to the position of the lens 220. For example, the Hall sensor 110 outputs a value of 0 when the lens 220 is in the macro position, and the ADC 130 outputs a value of 1023 (=CODE_M) when the lens 220 is in the infinity position. It can be designed to output a voltage value (VO) to output a value.

The Hall sensor 110, the amplification unit 120, and the ADC 130 may constitute the sensor unit 100.

The controller 140 may receive a command provided by the host 30 through the host clock input terminal 171 and the host data input terminal 172. The host 30 may provide a command for the focal length of the lens 220 to have a value suitable for the user's intention. Accordingly, in an embodiment, the host 30 may receive a user's input through the user interface 40.

A command provided by the host 30 through the host data input terminal 172 may include a target position value PT indicating an intended target position of the lens.

The controller 140 may provide a driving current control value to the driving unit 150, and the driving unit 150 may provide a driving current I to the VCM 210 according to the driving current control value.

The control unit 140 may include an error detection unit 141 and a PID control unit 142.

The error detection unit 141 may receive a value regarding the current position value PC of the lens from the ADC 130 and may receive the target position value PT through the host data input terminal 172. The error detection unit 141 may compare the current position value PC and the target position value PT to determine and output an error value err.

The PID control unit 142 may generate the driving current control value to be provided to the driving unit 150 based on the error value err.

7 is a graph for explaining a driving period and a disturbance detection period defined according to an embodiment of the present invention.

The horizontal axis of FIG. 7 is a time axis, and the vertical axis of FIG. 7 indicates a position of the lens 220 along the optical axis.

Reference numeral 51 of FIG. 7 is a graph showing a position of a lens over time.

A lens position change command meaning to change the target position of the lens may be intermittently or continuously provided to the VCM driving apparatus 10 through the host data input terminal 172. In FIG. 7, the time points at which the lens position change command is input to the VCM driving device 10 are the eleventh time point t11 and the 21st time point t21.

The controller 140 may change the target position value PT shown in FIG. 6 according to the lens position change command.

In the driving section defined in an embodiment of the present invention, from a point in time when the position of the lens 220 starts to change according to a new lens position change command, the motion state of the lens 220 is the new lens position change command. It can be defined as the time point from the new target position to the normal state.

The disturbance detection section defined in an embodiment of the present invention may be defined as a section other than the driving section. Alternatively, the disturbance detection period may be defined as a time period in which the motion state of the lens has a normal state after the driving period.

In FIG. 7, the driving section is an eleventh time section (P11) and a 12th time section (P12), and the disturbance detection section is presented as a 21st time section (P21) and a 22nd time section (P22).

In one embodiment of the present invention, the control unit 140 may change the PID coefficients of the PID control unit 142 based on a time point at which the lens position change command is received. In addition, the controller 140 may change the PID coefficients of the PID controller 142 based on a point in time when the motion state of the lens 220 whose position is changed according to the lens position change command is stabilized.

In step S10, when receiving a new lens position change command, the control unit 140 determines a new target position value PT according to the lens position change command, and sets the PID coefficients of the PID control unit 142 to a predetermined driving PID. Can be changed by coefficient.

In step S20, in a state in which the PID coefficients of the PID control unit 142 are already changed to a predetermined driving PID coefficient, or at the same time as the PID coefficients of the PID control unit 142 are changed to a predetermined driving PID coefficient, or the PID control unit ( While substantially changing the PID coefficients of 142 to the predetermined driving PID coefficients, the control unit 140 may provide the determined new target position value PT to the error detection unit 141.

In step S30, the controller 140 may change the PID coefficients of the PID controller 142 into a predetermined oscillation PID coefficient after the predetermined first time period has passed.

In this case, the predetermined first time period may mean a time period in which the motion state of the lens 220 is converted from a transient state to a normal state. The first time period may be the same as the driving period.

At this time, when the driving PID coefficient is applied, the phase of the signal transmission system using the error value (i.e., input signal) (err) as an input signal and the current position value (i.e., feedback signal) (PC) as an output signal Margin is defined as a driving phase margin value, and when the oscillation PID coefficient is applied, a phase margin of the signal transmission system may be defined as an oscillation phase margin value. In this case, the driving PID coefficients and the oscillation PID coefficients may have a relationship such that the oscillation phase margin value is greater than the driving phase margin value.

In an embodiment, it may be assumed that the proportional gain to the driving period has a first proportional gain value P1, and the integral gain to the driving period has a first integral gain value I1. In addition, the proportional gain to the disturbance detection period may have a second proportional gain value P2, and the integral gain to the disturbance detection period may have a second integral gain value I2. In this case, in an embodiment of the present invention, the controller 140 controls the second proportional gain value P2 to have a value smaller than the first proportional gain value P1, and the second integral gain value I2 is It can be controlled to be smaller than 1 integral gain value (I1). As a result, it is possible to have a relationship that makes the second phase margin value larger than the first phase margin value.

8 is a flow chart showing a method of controlling a driving device provided according to an embodiment of the present invention.

The driving apparatus control method includes: a sensor unit 100 for outputting a current position value PC of the lens 220 as a feedback signal; An error detection unit 141 for generating an error value err by comparing the target position value PT determined according to the input lens position change command with the current position value; A PID controller 142 generating a driving current control value based on the error value; And a driving unit 150 for outputting a current for driving the lens based on the driving current control value, and controlling the operating characteristics of the driving device. It relates to the control method.

In step S100, when a new lens position change command is input, the driving device determines a new target position value according to the new lens position change command, uses a signal input to the PID control unit as an input signal, and the sensor unit This is a first setting changing step of changing a setting of the driving device so that a phase margin of a signal transmission system using an output signal as an output signal is reduced.

Step S100 may include changing the PID coefficients of the PID control unit into predetermined driving PID coefficients.

In step S200, the driving device may provide the determined new target position value to the error detection unit.

Step S300 is a second setting changing step of changing the setting of the driving device so that the phase margin of the signal transmission system increases after a predetermined time.

Step S300 may include changing the PID coefficients of the PID control unit to a predetermined oscillation PID coefficient.

In this case, the second integral gain value I2 according to the oscillation PID coefficient may have a value smaller than the first integral gain value I1 according to the driving PID coefficient.

In addition, the second proportional gain value P2 according to the oscillation PID coefficient may have a value smaller than the first proportional gain value P1 according to the driving PID coefficient.

9 shows the structure of a user device provided according to an embodiment of the present invention.

The user device 1 may include a camera module device 50, a host 30, a user interface 40, a CPU 50, and a memory 60. The camera module device 50 may include the driving device 10 and the imaging device 20 according to the embodiment of the present invention described above.

By using the above-described embodiments of the present invention, those belonging to the technical field of the present invention will be able to easily implement various changes and modifications within the scope not departing from the essential characteristics of the present invention. The content of each claim in the claims may be combined with other claims having no citation relationship within the range that can be understood through the present specification.

10: drive device
100: sensor unit
141: error detection unit
142: PID control unit
150: drive unit
220: lens

Claims (9)

A sensor unit 100 for outputting (as a feedback signal) the current position value PC of the lens 220; An error detection unit 141 for generating an error value err by comparing the target position value PT determined according to the input lens position change command with the current position value; A PID controller 142 generating a driving current control value based on the error value; And a driving unit 150 for outputting a current for driving the lens based on the driving current control value, comprising: a driving device control method for controlling an operating characteristic of the driving device,
When a new lens position change command is input, the driving device determines a new target position value according to the new lens position change command, uses a signal input to the PID control unit as an input signal, and outputs a signal output by the sensor unit as an output signal. A first setting changing step of changing the setting of the driving device so that the phase margin of the signal transmission system is reduced;
Providing, by the driving device, the determined new target position value to the error detection unit; And
A second setting changing step of changing, by the driving device, a setting of the driving device such that a phase margin of the signal transmission system increases after a predetermined time;
Containing,
Driving device control method. The method of claim 1,
The first setting changing step includes changing the PID coefficients of the PID control unit into predetermined driving PID coefficients,
The second setting changing step includes changing the PID coefficients of the PID control unit to a predetermined oscillation PID coefficient,
The second proportional gain value P2 according to the oscillation PID coefficient has a value smaller than the first proportional gain value P1 according to the driving PID coefficient,
Driving device control method. The method of claim 1,
The first setting changing step includes changing the PID coefficients of the PID control unit into predetermined driving PID coefficients,
The second setting changing step includes changing the PID coefficients of the PID control unit to a predetermined oscillation PID coefficient,
The second integral gain value I2 according to the oscillation PID coefficient has a value smaller than the first integral gain value I1 according to the driving PID coefficient,
Driving device control method. The method of claim 3, wherein the second proportional gain value (P2) according to the oscillation PID coefficient has a value smaller than the first proportional gain value (P1) according to the driving PID coefficient. The method of claim 1, wherein the new lens position change command is provided from a host outside the driving device. A sensor unit for outputting a current position value of the lens (as a feedback signal);
An error detection unit for generating an error value by comparing the target position value determined according to the input lens position change command and the current position value;
A PID control unit that generates a driving current control value based on the error value; And
A driving unit outputting a current for driving the lens based on the driving current control value;
Including,
When a new lens position change command is input, a new target position value is determined according to the new lens position change command, a signal input to the PID control unit is used as an input signal, and a signal output from the sensor unit is used as an output signal. A first setting changing step of changing a setting of the driving device so that the phase margin of is decreased;
Providing the determined new target position value to the error detection unit; And
A second setting changing step of changing a setting of the driving device to increase a phase margin of the signal transmission system after a predetermined time;
Is adapted to perform the operation characteristic control method comprising
Drive. The method of claim 6,
The first setting changing step includes changing the PID coefficients of the PID control unit into predetermined driving PID coefficients,
The second setting changing step includes changing the PID coefficients of the PID control unit to a predetermined oscillation PID coefficient,
The second integral gain value I2 according to the oscillation PID coefficient has a value smaller than the first integral gain value I1 according to the driving PID coefficient,
The second proportional gain value P2 according to the oscillation PID coefficient has a value smaller than the first proportional gain value P1 according to the driving PID coefficient,
Drive. The driving device of claim 6; And
An imaging device 20 including the lens;
Containing,
Camera module device. The camera module device of claim 7;
A host 30 providing the lens position change command; And
User interface 40 for providing user input to the host
Containing,
User device.

Images