Patent Description:
Document <CIT> discloses a Vertical Cavity Surface Emitting Lasers (VCSEL) illuminator module.

Document <CIT> discloses a light source driving device that emits laser light and a light emitting device.

Document <CIT> discloses a beam projector module.

Document <CIT> discloses a housing for a light source mounted on a substrate.

Document <CIT> discloses a laser scanning projection display and a method for controlling the same.

Document <CIT> discloses a virtual image display optical system.

Document <CIT> discloses an optical component, a monitoring system and method thereof, an active lighting module, and a terminal.

As vehicles continuously increase, driving pressure on roads becomes increasingly higher. In addition, when driving, a driver often needs to lower the head to check a mobile phone or a dashboard, which inevitably increases a risk during driving. Therefore, an in-vehicle head-up display emerges accordingly.

A working principle of the in-vehicle head-up display is generally as follows: A laser light source emits laser light, and then a micro-electro-mechanical system scans the laser light onto a diffuser film. In this case, the diffuser film may be considered as an area light, and light emitted from the diffuser film finally projects into a windshield, so as to form a virtual image on a side of the windshield outside the vehicle. The virtual image may be used to display information on a device such as a dashboard or a mobile phone, so as to avoid an accident because the driver lowers the head to check the mobile phone or the dashboard.

However, due to a position shift of the diffuser film, the laser light scanned by the micro-electro-mechanical system may be directly emitted at the windshield, and finally emitted into eyes of the driver, thereby causing harm.

Therefore, it is necessary to detect the shift of the diffuser film in time to prevent the driver from being harmed.

Embodiments of this application provide a head-up display and a control method for the head-up display according to the independent claims, to detect the shift of the diffuser film.

A first example provides an apparatus for detecting a shift of a diffuser film, including a power supply, a conductive module, and a detection module; and
a relatively fixed position relationship exists between the conductive module and the diffuser film.

When the diffuser film is in a first position, the conductive module is connected to the power supply to form a closed loop.

When the diffuser film is shifted from the first position to a second position, a position of the conductive module changes to make the closed loop open, where the second position may have a plurality of options.

A shift distance from the second position to the first position is greater than a preset distance, and the preset distance may be set based on an actual situation, for example, may be determined based on a size of the conductive module and a related position relationship between the conductive module and the diffuser film.

The detection module is configured to detect whether the closed loop is opened, and when the closed loop is opened, it may be determined that the diffuser film is shifted.

In this example, when the diffuser film is in the first position, the conductive module is connected to the power supply to form a closed loop. When the diffuser film is shifted from the first position to the second position, the closed loop is opened. Based on that the detection module detects that the closed loop is opened, it may be determined that the diffuser film is shifted, so as to remind a user in time.

Further, the diffuser film is fastened to a bearer module, the bearer module may have a plurality of structures, and the diffuser film may also be fastened to the bearer module in a plurality of manners.

The conductive module is connected to the bearer module, and the conductive module may also be connected to the bearer module in a plurality of manners. For example, the conductive module may be pasted to the bearer module, or may be fastened to the bearer module by using a fastening component such as a screw.

This example provides a feasible solution for forming a relatively fixed position relationship, that is, the conductive module is connected to the diffuser film by using the bearer module.

Further, the bearer module includes a first frame.

The diffuser film is in the first frame, and the diffuser film may be adhered to the first frame by using a double-sided tape.

The conductive module is fastened to the first frame, and there are a plurality of fastening manners. For example, the conductive module may be fastened to the first frame by using a screw.

This example provides a feasible solution for connecting the diffuser film to the bearer module. Specifically, the bearer module includes the first frame, and the diffuser film may be adhered to the first frame.

Additionally, the bearer module further includes a foot. The foot may have a plurality of structures, and there may be a plurality of feet.

The foot is connected to the first frame, and is configured to support the first frame.

The conductive module is disposed below the foot and connected to the foot.

This example provides a feasible solution for connecting the conductive module to the first frame, that is, the conductive module is connected to the foot supporting the first frame.

In an alternative implementation, which is not an embodiment of the present invention but helpful for understanding certain aspects thereof, the bearer module includes a second frame and a third frame, and the conductive module includes a screw.

A first through hole is disposed in the second frame, and a second through hole is disposed in the third frame.

The screw fastens the second frame and the third frame by using the first through hole and the second through hole.

The diffuser film is fastened between the second frame and the third frame.

This implementation provides another structure of the bearer module, that is, the bearer module includes the second frame and the third frame that are connected to each other. Based on this structure, the conductive module is a screw for fastening the second frame and the third frame.

Based on the first example, the detection module may include a first resistor, a second resistor, a detection submodule, a first connection end, and a second connection end.

A power supply end of the power supply is connected to a first end of the first resistor.

A first end of the second resistor is connected to a second end of the first resistor, and a second end of the second resistor is grounded.

The first connection end is connected to the second end of the first resistor, and the second connection end is grounded.

When the diffuser film is in the first position, a first end of the conductive module is connected to the first connection end, and a second end of the conductive module is connected to the second connection end.

When the diffuser film is shifted from the first position to the second position, the first end of the conductive module is disconnected from the first connection end, and/or the second end of the conductive module is disconnected from the second connection end.

The detection submodule is connected to the second end of the first resistor, and is configured to detect a voltage of the second end of the first resistor, so as to determine that the closed loop is opened.

This example provides a feasible solution of the detection module, that is, determining, by detecting a voltage at a point in the closed loop, that the closed loop is opened.

A second aspect of embodiments of this application provides a head-up display, including a laser light source, a micro-electro-mechanical system, a diffuser film, and an apparatus for detecting a shift of the diffuser film. the apparatus comprises a power supply, a conductive module, and a detection module; a relatively fixed position relationship exists between the conductive module and the diffuser film; when the diffuser film is in a first position, the conductive module is connected to the power supply to form a closed loop; when the diffuser film is shifted from the first position to a second position, a position of the conductive module changes to make the closed loop open; a shift distance from the second position to the first position is greater than a preset distance; the detection module is configured to detect that the closed loop is opened; the diffuser film is fastened to a bearer module; the conductive module is connected to the bearer module; the bearer module comprises a first frame; the diffuser film is in the first frame, and the diffuser film is adhered to the first frame; the conductive module is fastened to the first frame; the bearer module further comprises a foot; the foot is connected to the first frame, and is configured to support the first frame; the conductive module is disposed below the foot and connected to the foot.

When the diffuser film is in the first position, laser light emitted by the laser light source is scanned by the micro-electro-mechanical system and incident on the diffuser film.

When the diffuser film is in the second position, the diffuser film deviates from an optical path of the laser light scanned by the micro-electro-mechanical system, so that the laser light emitted by the laser light source cannot be incident on the diffuser film after being scanned by the micro-electro-mechanical system.

In this embodiment of this application, when the diffuser film is in the first position, the laser light emitted by the laser light source is scanned by the micro-electro-mechanical system and incident on the diffuser film, and a conductive module is connected to a power supply to form a closed loop. When the diffuser film is shifted from the first position to the second position, the diffuser film deviates from the optical path of the laser light scanned by the micro-electro-mechanical system, so that the laser light emitted by the laser light source cannot be incident on the diffuser film after being scanned by the micro-electro-mechanical system, and the closed loop is opened. Therefore, based on that a detection module detects that the closed loop is opened, it may be determined that the diffuser film is shifted, so as to remind a user in time.

Based on the second aspect, embodiments of this application provide a first implementation of the second aspect, and the head-up display further includes a bearer module.

The diffuser film is fastened to the bearer module.

This embodiment of this application provides a feasible solution for fastening the diffuser film in the head-up display.

Based on the second aspect or the first implementation of the second aspect, embodiments of this application provide a second implementation of the second aspect, and the head-up display further includes a control module.

The control module may be connected to the detection module and the laser light source, and is configured to control the laser light source to be turned off when it is detected that the closed loop is opened.

In this embodiment of this application, the control module controls the laser light source to be turned off when it is detected that the closed loop is opened, so as to prevent the laser light emitted by the laser light source from being directly emitted into eyes of a driver without passing through the diffuser film.

A third aspect of embodiments of this application provides a control method for the head-up display according to any one of the implementations of the second aspect of embodiments of this application, including:.

In this embodiment of this application, when the closed loop is opened, a control module controls the laser light source in the head-up display to be turned off, so as to prevent laser light emitted by the laser light source from being directly emitted into eyes of a driver without passing through a diffuser film. When the closed loop is closed, the control module controls the laser light source in the head-up display to be turned on to ensure normal use of the head-up display.

In the technical solutions provided in embodiments of this application, the conductive module has a relatively fixed position relationship with the diffuser film. When the diffuser film is in the first position, the conductive module is connected to the power supply to form a closed loop. When the diffuser film is shifted from the first position to the second position, the closed loop is opened. Based on that the detection module detects that the closed loop is opened, it may be determined that the diffuser film is shifted, so as to remind the user in time.

The following describes technical solutions in embodiments of this application with reference to the accompanying drawings in embodiments of this application.

Embodiments of this application may be applied to an imaging system shown in <FIG>. The imaging system mainly includes a head-up display (Head Up Display, HUD) and a windshield (Windshield). The head-up display is configured to project light to the windshield to generate a virtual image on a side of the windshield outside a vehicle. The virtual image may be used to display various information, for example, may be used to display information on a device such as a dashboard or a mobile phone.

Specifically, the head-up display includes an image generation unit and an optical mirror group. Optionally, a lens is disposed on an outer wall of the image generation unit, and the lens is located on an optical path of light emitted from the image generation unit.

The image generation unit includes a laser light source, a micro-electro-mechanical system (MEMS, Micro Electro Mechanical System), and a diffuser film. The laser light source emits laser light, and then the micro-electro-mechanical system scans the laser light onto the diffuser film. Finally, the laser light passes through the diffuser film and projects to the windshield under an action of the optical mirror group.

A structure of the diffuser film may be shown in <FIG>, including a substrate with light transmittance and a diffusion layer disposed on a surface of the substrate. A material of the substrate may be polyethylene terephthalate (Polyethylene terephthalate, PET). The diffusion layer includes optical astigmatic particles.

Based on a function of the diffusion layer, the laser light is reflected, refracted, or scattered when passing through the diffuser film, and becomes uniform and gentle and does not harm eyes. Therefore, the diffuser film may also be considered as an area light.

In the imaging system shown in <FIG>, the optical mirror group includes a first reflector and a second reflector. Light emitted from the diffuser film is sequentially reflected by the first reflector and the second reflector, and finally projected onto the windshield.

An arrow in <FIG> represents a direction of propagation of light.

It should be understood that, because laser light has a large energy, to prevent the laser light from being emitted into eyes of a driver and causing harm, the diffuser film should be disposed in a proper position, so that the laser light passes through the diffuser film and then is emitted at the optical mirror group rather than being directly emitted at the optical mirror group. However, during use of the head-up display, the diffuser film may be shifted, causing the laser light to be directly emitted at the optical mirror group without passing through the diffuser film, and finally emitted into the eyes of the driver. In addition, because the head-up display is applied to a vehicle, impact and vibration may occur on the vehicle during driving, and the diffuser film is more prone to shift.

Therefore, an embodiment of this application provides an apparatus for detecting a shift of a diffuser film. The apparatus may be integrated into a same device as the diffuser film. For example, the apparatus may be integrated into a head-up display, and the apparatus may be directly or indirectly connected to the diffuser film, to detect that the diffuser film is shifted, so as to remind a user that the diffuser film is shifted, thereby avoiding causing harm.

Specifically, <FIG> is a schematic diagram of a first embodiment of an apparatus for detecting a shift of a diffuser film according to an embodiment of this application. This embodiment of this application provides an embodiment of an apparatus for detecting a shift of a diffuser film, including a power supply <NUM>, a conductive module <NUM>, and a detection module <NUM>.

An output voltage of the power supply <NUM> may be selected based on an actual requirement.

The conductive module <NUM> has a relatively fixed position relationship with the diffuser film. There may be one or more conductive modules <NUM>, and the conductive module <NUM> may have a plurality of structures. This is not limited in this embodiment of this application, for example, the conductive module <NUM> may be a conductive spring.

The relatively fixed position relationship may be formed in a plurality of manners, which is not limited in this embodiment of this application.

For example, the conductive module <NUM> may be connected to the diffuser film, so as to form a relatively fixed position relationship, where the connection may be a direct connection, or may be an indirect connection. The conductive module <NUM> may alternatively not be connected to the diffuser film, but has a relatively fixed position relationship with the diffuser film.

The following describes a manner in which the conductive module <NUM> is indirectly connected to the diffuser film. <FIG> is used as an example, and the diffuser film is fastened to a bearer module <NUM>. The conductive module <NUM> is connected to the bearer module <NUM>.

The bearer module <NUM> may have a plurality of structures, which is not limited in this embodiment of this application.

The diffuser film may be fastened to the bearer module <NUM> in a plurality of manners, and the manners may be related to the structures of the bearer module <NUM>. This is not limited in this embodiment of this application.

The conductive module <NUM> may be connected to the bearer module <NUM> in a plurality of manners. For example, the conductive module <NUM> may be pasted to the bearer module <NUM>, or may be fastened to the bearer module <NUM> by using a fastening component such as a screw. This is not limited in this embodiment of this application.

With reference to <FIG> and <FIG>, the following describes the structure of the bearer module <NUM>, a manner of fastening the diffuser film, and a manner of connecting the conductive module <NUM> to the bearer module <NUM>.

As shown in <FIG> and <FIG>, for example, the bearer module <NUM> includes a first frame <NUM>.

The diffuser film is in the first frame <NUM>, and the diffuser film is adhered to the first frame <NUM>.

It should be noted that the diffuser film may be adhered to the first frame <NUM> in a plurality of manners. For example, a double-sided tape may be disposed around the diffuser film, and the diffuser film is adhered to the first frame <NUM> by using the double-sided tape. <FIG> does not show the diffuser film.

The conductive module <NUM> is fastened to the first frame <NUM>, and the conductive module <NUM> is fastened to the first frame <NUM> in a plurality of manners. For example, the conductive module <NUM> may be directly fastened to the first frame <NUM>, or may be indirectly fastened to the first frame <NUM>.

As shown in <FIG> and <FIG>, as an implementable manner in which the conductive module <NUM> is indirectly fastened to the first frame <NUM>, the bearer module <NUM> further includes a foot <NUM>.

The foot <NUM> is connected to the first frame <NUM>, and is configured to support the first frame <NUM>.

The conductive module <NUM> is disposed below the foot <NUM> and connected to the foot <NUM>.

It should be noted that there may be one or more feet <NUM>. When there are a plurality of feet <NUM>, one conductive module <NUM> may be disposed below each foot <NUM>.

Based on the foregoing relatively fixed position relationship, when the diffuser film is in a first position, laser light passes through the diffuser film, and the conductive module <NUM> is connected to the power supply <NUM> to form a closed loop.

It may be learned from the foregoing description that there may be a plurality of conductive modules <NUM>. It is assumed that there are two conductive modules <NUM>, and the two conductive modules <NUM> may be connected in series in a same closed loop, or may be separately connected in different loops. For example, as shown in <FIG>, the bearer module <NUM> includes two feet <NUM>, one conductive module <NUM> is disposed below each foot <NUM>, and the two conductive modules <NUM> form a closed loop in series with the power supply <NUM>. The two conductive modules <NUM> may alternatively be connected in parallel, so as to form two closed loops with the power supply <NUM>.

When the diffuser film is shifted from the first position to a second position, the laser light does not pass through the diffuser film, and a position of the conductive module <NUM> changes to make the closed loop open, where a shift distance from the second position to the first position is greater than a preset distance.

It should be noted that the second position may have a plurality of cases. This is not limited in this embodiment of this application. The following provides specific description with reference to <FIG>, <FIG>, and <FIG>. Herein, it is first assumed that the position of the diffuser film in <FIG> is the first position.

The diffuser film may be shifted longitudinally from the first position to the second position. Specifically, as shown in <FIG>, the diffuser film is shifted upward from the first position to the second position, that is, the position of the diffuser film in <FIG> is the second position. The conductive module <NUM> is also shifted upward with the diffuser film, and both ends of the conductive module <NUM> are disconnected from the power supply <NUM>, so that the closed loop is opened.

The diffuser film may be shifted obliquely from the first position to the second position. Specifically, as shown in <FIG>, the diffuser film is shifted obliquely from the first position to one side to the second position, that is, the position of the diffuser film in <FIG> is the second position. The conductive module <NUM> is also shifted obliquely to one side with the diffuser film, and one end of the conductive module <NUM> is disconnected from the power supply <NUM>, so that the closed loop is opened.

In addition, the diffuser film may alternatively be shifted laterally from the first position to the second position, so that the conductive module <NUM> is also shifted laterally. Both ends of the conductive module <NUM> are disconnected from the power supply <NUM>, so that the closed loop is opened.

Therefore, in this embodiment of this application, the second position may have a plurality of cases, specifically including any position at which the closed loop can be opened.

It should be noted that the diffuser film is inevitably shifted during use, especially when the diffuser film is applied to a head-up display of a vehicle, the diffuser film is frequently shifted as the vehicle vibrates. Therefore, to prevent a slight shift of the diffuser film from causing the closed loop to be opened, in this embodiment of this application, the position of the conductive module <NUM> is properly disposed, so that only when the shift distance of the diffuser film is greater than the preset distance, the closed loop can be opened.

For ease of understanding, it may be learned from comparison between <FIG> and <FIG> that the diffuser film is shifted obliquely to one side from the first position shown in <FIG>. However, because the conductive module <NUM> has a specific thickness, both ends of the conductive module <NUM> are not disconnected from the power supply <NUM>. Through comparison between <FIG> and <FIG>, it may be learned that the diffuser film continues to be shifted on the basis of the position shown in <FIG>, and eventually is shifted to the second position shown in <FIG>. In this case, one end of the conductive module <NUM> is disconnected from the power supply <NUM>.

The preset distance may be determined based on a size of the conductive module <NUM> and a related position relationship between the conductive module <NUM> and the diffuser film. A specific determining method is not described in detail herein.

The detection module <NUM> is configured to detect whether the closed loop is opened. It may be understood that the detection module <NUM> may be connected to the closed loop, so as to detect that the closed loop is opened.

It should be noted that the detection module <NUM> may have a plurality of structures, which is not limited in this embodiment of this application. For example, the detection module <NUM> may be an ammeter connected in series in the closed loop.

In this embodiment of this application, when the diffuser film is in the first position, the conductive module <NUM> is connected to the power supply <NUM> to form a closed loop. When the diffuser film is shifted from the first position to the second position, the closed loop is opened. Based on that the detection module <NUM> detects that the closed loop is opened, it may be determined that the diffuser film is shifted, so as to remind a user in time.

It may be learned from <FIG> and related descriptions in <FIG> that the bearer module <NUM> includes the first frame <NUM> and the foot <NUM>. Correspondingly, the diffuser film may be adhered to the bearer module <NUM>, and the conductive module <NUM> may be disposed below the foot <NUM>. In addition, the bearer module <NUM> may have a plurality of structures. Correspondingly, there may be also a plurality of optional manners of connecting the diffuser film to the bearer module <NUM>, structures of the conductive module <NUM>, and manners of connecting the conductive module <NUM> to the bearer module <NUM>.

The following describes another embodiment, which is not an embodiment of the present invention but helpful for understanding certain aspects thereof, with reference to <FIG> and <FIG>. In this embodiment, a structure of the bearer module <NUM>, a manner of connecting the diffuser film to the bearer module <NUM>, a structure of the conductive module <NUM>, and a manner of connecting the conductive module <NUM> to the bearer module <NUM> are different from those shown in <FIG>. Specifically, as shown in <FIG>, in another embodiment of the apparatus for detecting a shift of a diffuser film provided in this embodiment of this application, the bearer module <NUM> includes a second frame <NUM> and a third frame <NUM>, and the conductive module <NUM> includes a screw.

The second frame <NUM> and the third frame <NUM> may have a plurality of structures. This is not limited in this embodiment of this application. <FIG> shows only one structure of each of the second frame <NUM> and the third frame <NUM>.

A first through hole is disposed in the second frame <NUM>, and a second through hole is disposed in the third frame <NUM>. <FIG> does not show the first through hole and the second through hole.

The screw fastens the second frame <NUM> and the third frame <NUM> by sequentially using the first through hole and the second through hole.

The diffuser film is fastened between the second frame <NUM> and the third frame <NUM>.

In this embodiment of this application, the screw not only functions to fasten the second frame <NUM> and the third frame <NUM>, but also functions as the conductive module <NUM>.

Specifically, as shown in <FIG>, the diffuser film is in the first position, and two ends of the screw are separately connected to the power supply <NUM> to form a closed loop.

Based on loosening of the screw, the screw falls off from the first through hole and the second through hole, the second frame <NUM> and the third frame <NUM> are separated, and the diffuser film cannot be fastened to the first position, so that the diffuser film is shifted. <FIG> is used as an example. It is assumed that the diffuser film is shifted to a position shown in <FIG>, that is, the second position, connections between the two ends of the screw and two ends of the power supply <NUM> are disconnected, so that the closed loop is opened.

In this embodiment of this application, the conductive module <NUM> is a screw, the diffuser film is shifted from the first position to the second position based on falling off of the screw, and the closed loop between the screw and the power supply <NUM> is opened. Therefore, in this embodiment of this application, by detecting that the closed loop is opened, it is determined that the diffuser film is shifted.

It may be learned from the foregoing description that the detection module <NUM> may have a plurality of structures. The following specifically describes a structure of the detection module with reference to <FIG> and <FIG>. As shown in <FIG>, the detection module <NUM> includes a first resistor R1, a second resistor R2, a detection submodule <NUM>, a first connection end Q, and a second connection end P.

A power supply end VCC of the power supply is connected to a first end A of the first resistor R1.

A first end C of the second resistor R2 is connected to a second end B of the first resistor R1, and a second end D of the second resistor R2 is grounded.

The first connection end Q is connected to the second end B of the first resistor R1, and the second connection end P is grounded.

As shown in <FIG>, when the diffuser film is in the first position shown in <FIG>, a first end F of the conductive module <NUM> is connected to the first connection end Q, and a second end E of the conductive module <NUM> is connected to the second connection end P, so that the conductive module <NUM> is connected to the power supply to form a closed loop.

As shown in <FIG>, when the diffuser film is shifted from the first position to the second position shown in <FIG>, the first end F of the conductive module <NUM> is disconnected from the first connection end Q, and/or the second end E of the conductive module <NUM> is disconnected from the second connection end P, so that the closed loop between the conductive module <NUM> and the power supply is opened. <FIG> shows only a case in which the first end F of the conductive module <NUM> is disconnected from the first connection end Q.

The detection submodule <NUM> is connected to the second end B of the first resistor R1, and is configured to detect a voltage of the second end B of the first resistor R1, so as to determine that the closed loop is opened.

It may be understood that when the first end F of the conductive module <NUM> is connected to the first connection end Q and the second end E of the conductive module <NUM> is connected to the second connection end P, the conductive module <NUM> is connected to the second resistor R2 in parallel. It is assumed that in this case, a voltage detected by the detection submodule <NUM> is a first voltage. When the first end F of the conductive module <NUM> is disconnected from the first connection end Q, and/or the second end E of the conductive module <NUM> is disconnected from the second connection end P, a branch on which the conductive module <NUM> is located is disconnected. It is assumed that in this case, a voltage detected by the detection submodule <NUM> is a second voltage.

It may be learned from circuit theory that the first voltage is lower than the second voltage. Therefore, if the detection submodule <NUM> detects a low voltage, it may be determined that the closed circuit is not opened. If the detection submodule <NUM> detects a high voltage, it may be determined that the closed loop is opened.

Based on the structure of the detection module shown in <FIG> and <FIG>, the apparatus for detecting a shift of a diffuser film shown in <FIG> may be shown in <FIG>.

<FIG> is a schematic diagram of a first embodiment of a head-up display according to an embodiment of this application. This embodiment of this application provides an embodiment of a head-up display, including a laser light source <NUM>, a micro-electro-mechanical system <NUM>, a diffuser film <NUM>, and the apparatus for detecting a shift of a diffuser film mentioned in any one of the foregoing embodiments.

When the diffuser film <NUM> is in a first position, laser light emitted by the laser light source <NUM> is scanned by the micro-electro-mechanical system <NUM>, then incident on the diffuser film <NUM>, passes through the diffuser film <NUM>, and finally exits the head-up display.

<FIG> is a schematic diagram of a second embodiment of a head-up display according to an embodiment of this application. As shown in <FIG>, the diffuser film <NUM> is in a second position, and the diffuser film <NUM> deviates from an optical path of the laser light scanned by the micro-electro-mechanical system <NUM>, that is, the laser light directly exits the head-up display without passing through the diffuser film <NUM>.

It should be noted that <FIG> show only one structure of the apparatus for detecting a shift of a diffuser film, and <FIG> shows only one case in which the diffuser film <NUM> is in the second position. Based on the foregoing embodiments, the apparatus for detecting a shift of a diffuser film is described in detail. This embodiment of this application is not described in detail herein. For details, refer to the apparatus for detecting a shift of a diffuser film described in <FIG>.

In this embodiment of this application, when the diffuser film <NUM> is in the first position, the laser light emitted by the laser light source <NUM> is scanned by the micro-electro-mechanical system <NUM> and incident on the diffuser film <NUM>, and the conductive module <NUM> is connected to the power supply <NUM> to form a closed loop. When the diffuser film <NUM> is shifted from the first position to the second position, the diffuser film <NUM> deviates from the optical path of the laser light scanned by the micro-electro-mechanical system <NUM>, that is, the laser light directly exits the head-up display without passing through the diffuser film <NUM>, and the closed loop is opened. Therefore, if the detection module <NUM> detects that the closed loop is opened, it may be determined that the diffuser film <NUM> is shifted, so as to remind the user in time.

Based on the foregoing embodiments, as can be learned from <FIG>, in another embodiment of the head-up display provided in this embodiment of this application, the head-up display further includes a bearer module <NUM>.

The diffuser film <NUM> is fastened to the bearer module <NUM>.

Based on the foregoing embodiments, as can be learned from <FIG>, in another embodiment of the head-up display provided in this embodiment of this application, the head-up display further includes a control module <NUM>.

The control module <NUM> is configured to control the laser light source <NUM> to be turned off when it is detected that the closed loop is opened.

The control module <NUM> may be connected to the detection module <NUM> to obtain a detection result of the detection module <NUM>. The control module may be further connected to the laser light source <NUM>, and is configured to control the laser light source <NUM> to be turned on or turned off.

It should be noted that the control module <NUM> and the detection module <NUM> may be integrated into one module. For example, referring to <FIG>, the control module <NUM> and the detection module <NUM> may be integrated into a micro control unit (Micro Control Unit, MCU). In this case, the power supply <NUM> in the apparatus for detecting a shift of a diffuser film may also be integrated into the MCU.

Specifically, a first end of the MCU serves as an output end of the power supply <NUM> (for example, the power supply end VCC in <FIG>), and is configured to supply power. A second end of the MCU is connected to a closed loop (for example, the second end B of the first resistor R1 in <FIG>), and is configured to detect that the closed loop is opened. A third end of the MCU is connected to the laser light source <NUM>, and is configured to control the laser light source <NUM> to be turned on or off. The MCU may be connected to a battery by using a direct current-direct current conversion circuit.

In this embodiment of this application, when the closed loop is opened, the control module <NUM> controls the laser light source <NUM> in the head-up display to be turned off, so as to prevent laser light emitted by the laser light source <NUM> from being directly emitted into eyes of a driver without passing through the diffuser film <NUM>. When the closed loop is closed, the control module <NUM> controls the laser light source <NUM> in the head-up display to be turned on to ensure normal use of the head-up display.

Referring to <FIG>, an embodiment of this application further provides a control method for the head-up display described in <FIG>, including:.

In this embodiment of this application, when the closed loop is opened, the control module controls the laser light source in the head-up display to be turned off, so as to prevent laser light emitted by the laser light source from being directly emitted into eyes of a driver without passing through a diffuser film. When the closed loop is closed, the control module controls the laser light source in the head-up display to be turned on to ensure normal use of the head-up display.

Claim 1:
A head-up display, comprising a laser light source (<NUM>), a micro-electro-mechanical system (<NUM>), a diffuser film (<NUM>), and an apparatus for detecting a shift of the diffuser film (<NUM>), wherein
the apparatus comprises a power supply (<NUM>), a conductive module (<NUM>), and a detection module (<NUM>);
a relatively fixed position relationship exists between the conductive module (<NUM>) and the diffuser film (<NUM>);
when the diffuser film (<NUM>) is in a first position, the conductive module (<NUM>) is connected to the power supply (<NUM>) to form a closed loop;
when the diffuser film (<NUM>) is shifted from the first position to a second position, a position of the conductive module (<NUM>) changes to make the closed loop open;
a shift distance from the second position to the first position is greater than a preset distance;
the detection module (<NUM>) is configured to detect that the closed loop is opened;
the diffuser film (<NUM>) is fastened to a bearer module (<NUM>);
the conductive module (<NUM>) is connected to the bearer module (<NUM>);
the bearer module (<NUM>) comprises a first frame (<NUM>);
the diffuser film (<NUM>) is in the first frame (<NUM>), and the diffuser film (<NUM>) is adhered to the first frame (<NUM>);
the conductive module (<NUM>) is fastened to the first frame (<NUM>);
the bearer module (<NUM>) further comprises a foot (<NUM>);
the foot (<NUM>) is connected to the first frame (<NUM>), and is configured to support the first frame (<NUM>);
the conductive module (<NUM>) is disposed below the foot (<NUM>) and connected to the foot (<NUM>);
when the diffuser film (<NUM>) is in the first position, laser light emitted by the laser light source (<NUM>) is scanned by the micro-electro-mechanical system (<NUM>) and incident on the diffuser film (<NUM>); and
when the diffuser film (<NUM>) is in the second position, the diffuser film (<NUM>) deviates from an optical path of the laser light scanned by the micro-electro-mechanical system (<NUM>).