Projection device and method for adjusting its field of view

Abstract

The present application discloses a projection device and a method for adjusting the field of view angle thereof, belonging to the field of projection display. The control circuit in the projection device is configured to determine a target distance between a target object and the projection device according to the signal emitted by the optical signal transmitting component and the signal received by the optical signal receiving component; adjust the receiving field of view angle of the optical signal receiving component to a target receiving field of view angle according to the target distance; and adjust the brightness of the laser light source according to the target distance. Since the size of the adjusted receiving field of view angle is negatively correlated with the length of the target distance, when the target object is relatively close to the projection device, the larger receiving field of view angle can increase the detection range of the optical signal receiving component, making the detection range of the target object more comprehensive, thereby improving the reliability of detecting the target object. At the same time, since the brightness of the laser light source can be adjusted according to the target distance, the human eyes are effectively protected.

Description

[0001] This application is a divisional application of Chinese Invention Application No. 202010419446.3 (filed on May 18, 2020), with the invention title: Projection Device and Its Field of View Angle Adjustment Method. Technical Field

[0002] The present disclosure relates to the field of projection display, and particularly to a projection device and its field of view angle adjustment method. Background Art

[0003] Currently, after the laser emitted by the projection device is projected onto the projection screen, an image can be projected onto the projection screen. However, since the laser emitted by the projection device has a high brightness, when the user is close to the projection screen, the laser may cause harm to the human eye.

[0004] In related technologies, the projection device may include a pyroelectric sensor and a control circuit. When a human body within the sensing range of the pyroelectric sensor moves, the pyroelectric sensor can detect the infrared signal radiated by the human body and amplify the received infrared signal. Then, the amplified infrared signal is converted into an electrical signal and sent to the control circuit. When the control circuit determines that the electrical signal is greater than the signal threshold, it can reduce the brightness of the projection screen, thereby reducing the harm caused by the laser emitted by the projection device to the human eye.

[0005] However, since the pyroelectric sensor can only detect the infrared signal radiated by the human body when the human body moves, the reliability of human body detection is low, and thus the safety of protecting the human eye is low. Summary of the Invention

[0006] Embodiments of the present disclosure provide a projection device and its field of view angle adjustment method, which can solve the problem in related technologies that the pyroelectric sensor can only detect the infrared signal radiated by the human body when the human body moves, resulting in low safety of protecting the human eye. The technical solutions are as follows:

[0007] On the one hand, a projection device is provided. The projection device includes: an optical signal transmitting component and an optical signal receiving component disposed on one side of the host of the projection device. The optical signal transmitting component and the optical signal receiving component are disposed on the upper surface or the front side surface of the housing of the projection device, and the optical signal receiving component includes a plurality of photosensors;

[0008] The optical signal transmitting component is configured to emit an optical signal along a preset field of view angle range;

[0009] The optical signal receiving component is configured to receive the optical signal reflected by a target in front of or on the side of the projection device;

[0010] Further, it further includes a control circuit, which is respectively connected to the optical signal transmitting component and the optical signal receiving component; and is configured to determine a target distance between the target object and the projection device according to the optical output time value of the optical signal transmitting component and the optical reception time value of the optical signal receiving component;

[0011] Further, the control circuit is further configured to adjust a reception field angle of the optical signal receiving component according to the target distance, and the size of the reception field angle is negatively correlated with the length of the target distance;

[0012] Further, the optical signal receiving component is further configured to receive an optical reflection signal at the adjusted reception field angle,

[0013] Further, the control circuit is further configured to adjust the brightness of the laser light source according to the target distance.

[0014] On the other hand, a method for adjusting a field angle is provided. The method is applied to a control circuit in a projection device, and the projection device further includes: an optical signal transmitting component and an optical signal receiving component disposed on one side of a main body of the projection device, the optical signal transmitting component and the optical signal receiving component are disposed on an upper surface or a front side surface of a housing of the projection device, and the optical signal receiving component includes a plurality of photosensors. Wherein, the control circuit is respectively connected to the optical signal transmitting component and the optical signal receiving component, and the method includes:

[0015] Determining a target distance between the target object and the projection device according to the optical output time value of the optical signal transmitting component and the optical reception time value of the optical signal receiving component;

[0016] Adjusting a reception field angle of the optical signal receiving component according to the target distance, where the size of the reception field angle is negatively correlated with the length of the target distance, so that the optical signal receiving component receives an optical reflection signal at the adjusted reception field angle;

[0017] Adjusting the brightness of the laser light source according to the target distance.

[0018] The beneficial effects brought by the technical solutions provided in the embodiments of the present disclosure at least include:

[0019] Embodiments of the present disclosure provide a projection device and a method for adjusting the field of view angle thereof. The control circuit in the projection device can adjust the field of view angle of the optical signal receiving component according to the target distance between the target object and the projection device. Since the size of the adjusted field of view angle is negatively correlated with the length of the target distance, when the target object is relatively close to the projection device, the larger field of view angle can increase the detection range of the optical signal receiving component, making the detection range of the target object more comprehensive, thereby improving the reliability of detecting the target object. Moreover, since the field of view angle of the optical signal receiving component can be dynamically adjusted according to the distance, the flexibility of detecting the target object is improved. At the same time, since the brightness of the laser light source can be adjusted according to the target distance, the human eyes are effectively protected. Description of the Drawings

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present disclosure. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0021] Figure 1 is a schematic structural diagram of a projection device provided by an embodiment of the present disclosure;

[0022] Figure 2 is a schematic structural diagram of another projection device provided by an embodiment of the present disclosure;

[0023] Figure 3 is a flowchart of a method for adjusting the field of view angle provided by an embodiment of the present disclosure;

[0024] Figure 4 is a flowchart of another method for adjusting the field of view angle provided by an embodiment of the present disclosure;

[0025] Figure 5 is a schematic structural diagram of another projection device provided by an embodiment of the present disclosure;

[0026] Figure 6 is a schematic structural diagram of yet another projection device provided by an embodiment of the present disclosure;

[0027] Figure 7 is a schematic diagram of the optical signal transmitting component transmitting an optical signal and the optical signal receiving component receiving the optical signal reflected by the target object provided by an embodiment of the present disclosure;

[0028] Figure 8 is a schematic diagram of the target receiving field of view angle corresponding to the target distance provided by an embodiment of the present disclosure;

[0029] Figure 9It is a schematic diagram of the switch state of the photosensor corresponding to a 30-degree field of view angle of the optical signal receiving component provided by an embodiment of the present disclosure;

[0030] Figure 10 It is a schematic diagram of the switch state of the photosensor corresponding to a 25-degree field of view angle of the optical signal receiving component provided by an embodiment of the present disclosure;

[0031] Figure 11 It is a schematic diagram of the switch state of the photosensor corresponding to a 15-degree field of view angle of the optical signal receiving component provided by an embodiment of the present disclosure;

[0032] Figure 12 It is a schematic diagram of the structure of another projection device provided by an embodiment of the present disclosure;

[0033] Figure 13 It is a schematic diagram of a process of adjusting an aperture provided by an embodiment of the present disclosure. Detailed implementation manners

[0034] To make the objectives, technical solutions, and advantages of the present disclosure clearer, the following will further describe the embodiments of the present disclosure in detail with reference to the accompanying drawings.

[0035] Figure 1 It is a schematic diagram of the structure of a projection device provided by an embodiment of the present disclosure. Figure 2 It is a schematic diagram of the structure of another projection device provided by an embodiment of the present disclosure. As Figure 1 and Figure 2 shown, the projection device may include: a control circuit 10, an optical signal transmitting component 20 disposed on one side of the host of the projection device, and an optical signal receiving component 30. The optical signal transmitting component 20 and the optical signal receiving component 30 are disposed on the upper surface or the front side of the housing 00 of the projection device. For example, the optical signal transmitting component 20 and the optical signal receiving component 30 may be disposed at the area 01 on the upper surface of the housing 00, the area 02 and the area 03 on the front side. The optical signals emitted by the optical signal transmitting component 20 at different positions may form a range F, and the optical signal receiving component 30 may receive the optical signals reflected by the target object within the range F. The optical signal receiving component 30 may include a plurality of photosensors arranged in an array.

[0036] Among them, the control circuit 10 is respectively connected to the optical signal transmitting component 20 and the optical signal receiving component 30. The control circuit 10 is used to control the optical signal transmitting component 20 to emit an optical signal. Optionally, the optical signal receiving component 30 may include M×N photosensors arranged in an array, where M is the number of rows of the photosensors and N is the number of columns of the photosensors, and both M and N are positive integers greater than 1. The photosensor may be a photodiode.

[0037] Figure 3It is a flowchart of a field of view adjustment method provided by an embodiment of the present disclosure. This adjustment method is applied to Figure 1 and Figure 2 in the control circuit 10 of the projection device shown. Referring to Figure 1 and Figure 2 it can be seen that the projection device may further include an optical signal transmitting component 20 and an optical signal receiving component 30 disposed on one side of the host of the projection device. The optical signal transmitting component 20 and the optical signal receiving component 30 are disposed on the upper surface or the front side of the housing 00 of the projection device, and the optical signal receiving component 30 may include a plurality of photosensors. Among them, the control circuit 10 is respectively connected to the optical signal transmitting component 20 and the optical signal receiving component 30. As shown in Figure 3 the method may include:

[0038] Step 301: Determine the target distance between the target object and the projection device according to the light output time value of the optical signal transmitting component and the light receiving time value of the optical signal receiving component.

[0039] In an embodiment of the present disclosure, the optical signal transmitting component may emit an optical signal along a preset field of view range, and the optical signal receiving component may receive the optical signal reflected by a target object in front of or on the side of the projection device. The control circuit may determine the target distance between the target object and the projection device according to the light output time value of the optical signal transmitting component and the light receiving time value of the optical signal receiving component.

[0040] Optionally, the target object may be a person or an animal located in the transmission optical path of the optical signal emitted by the optical signal transmitting component.

[0041] Step 302: Adjust the receiving field of view angle of the optical signal receiving component according to the target distance.

[0042] After determining the target distance between the target object and the projection device, the control circuit may adjust the receiving field of view angle of the optical signal receiving component according to the target distance, so that the optical signal receiving component receives the light reflection signal with the adjusted receiving field of view angle. The size of the receiving field of view angle is negatively correlated with the length of the target distance. That is, the longer the target distance, the smaller the receiving field of view angle; the shorter the target distance, the larger the receiving field of view angle. Among them, the receiving field of view angle of the optical signal receiving component refers to the range within which the optical signal receiving component can detect an optical signal, and the larger the receiving field of view angle, the larger the range within which the optical signal receiving component can detect an optical signal. It should be noted that after the projection device is started, the receiving field of view angle of the optical signal receiving component may be an initially stored initial receiving field of view angle. The initial receiving field of view angle may be the maximum receiving field of view angle of the optical signal receiving component.

[0043] Step 303: Adjust the brightness of the laser light source according to the target distance.

[0044] The control circuit can also adjust the brightness of the laser light source according to the target distance to protect the human eyes.

[0045] In summary, the embodiments of the present disclosure provide a method for adjusting the field of view angle. The adjustment method can adjust the receiving field of view angle of the optical signal receiving component according to the target distance between the target object and the projection device, so that the optical signal receiving component receives the optical reflection signal with the adjusted receiving field of view angle. Since the size of the adjusted receiving field of view angle is negatively correlated with the length of the target distance, when the target object is relatively close to the projection device, the larger receiving field of view angle can increase the detection range of the optical signal receiving component, making the detection range of the target object more comprehensive, thereby improving the reliability of the detection of the target object. And, since the receiving field of view angle of the optical signal receiving component can be dynamically adjusted according to the distance, the flexibility of the detection of the target object is improved. At the same time, since the brightness of the laser light source can be adjusted according to the target distance, the human eyes are effectively protected.

[0046] Figure 4 The flowchart of another method for adjusting the field of view angle provided by the embodiments of the present disclosure. This adjustment method is applied to Figure 1 and Figure 2 In the control circuit 10 of the projection device shown, referring to Figure 1 and Figure 2 It can be seen that the projection device may further include an optical signal transmitting component 20 and an optical signal receiving component 30 disposed on one side of the host of the projection device. The optical signal transmitting component 20 and the optical signal receiving component 30 are disposed on the upper surface or the front side of the housing 00 of the projection device. The optical signal receiving component 30 may include a plurality of photosensors. Among them, the control circuit 10 is respectively connected to the optical signal transmitting component 20 and the optical signal receiving component 30. As Figure 4 shown, the method may include:

[0047] Step 401, in response to a start instruction, start the optical signal transmitting component.

[0048] Referring to Figure 1 , the projection device may further include a multimedia control component 40, and the multimedia control component 40 is connected to the control circuit 10. A power-on button may be provided on the projection device. After detecting a click operation on the power-on button, the multimedia control component 40 may generate a start instruction and may send the start instruction to the control circuit 10. The control circuit 10 may start the optical signal transmitting component 20 in response to the start instruction.

[0049] Alternatively, the startup instruction may be triggered by the user via a remote control. After receiving the startup instruction sent by the remote control, the multimedia control component 40 may send the startup instruction to the control circuit 10. The control circuit 10 may respond to the startup instruction and activate the optical signal transmitting component 20.

[0050] Alternatively, the startup instruction may be triggered by the user via a projection client installed in the terminal. The display interface of the projection client may display a startup button. After detecting a click operation by the user on the startup button, the projection client may generate a startup instruction. Subsequently, the projection client may send the startup instruction to the multimedia control component 40. After receiving the startup instruction sent by the projection client, the multimedia control component 40 may send the startup instruction to the control circuit 10. The control circuit 10 may respond to the startup instruction and activate the optical signal transmitting component 20.

[0051] Optionally, Figure 5 is a schematic structural diagram of another projection device provided by an embodiment of the present disclosure. Figure 6 is a schematic structural diagram of yet another projection device provided by an embodiment of the present disclosure. Refer to Figure 5 and Figure 6 According to this, the optical signal transmitting component 20 may include a laser driver component 21 and a laser 22. The control circuit 10 may respond to the startup instruction and send an enable signal and a laser drive current signal to the laser driver component 21. The laser driver component 21 may respond to the enable signal and the laser drive current signal and provide a laser drive current to the laser 22. The laser 22 may emit an optical signal under the drive of the laser drive current. The safety level of the laser 22 meets the requirements of laser safety level 1, and the optical signal received by the optical signal receiving component emitted by the laser 22 may be infrared light with a wavelength of 940 nanometers (nm). Optionally, the laser 22 may be a vertical cavity surface emitting laser (VCSEL).

[0052] Step 402: Determine the transmission duration of the optical signal according to the optical output time value of the optical signal transmitting component and the optical reception time value of the optical signal receiving component.

[0053] In an embodiment of the present disclosure, after the control circuit activates the optical signal transmitting component, refer to Figure 7, the optical signal transmitting component 20 can emit an optical signal along a preset field of view angle range, and the optical signal receiving component 30 can receive the optical signal reflected by a target in front of or on the side of the projection device. The control circuit can determine the optical output time value t1 of the optical signal transmitting component 20 for emitting the optical signal and the optical reception time value t2 of the optical signal receiving component 30 for receiving the optical signal, and determine the transmission duration T of the optical signal according to the optical output time value t1 and the optical reception time value t2. The T = t2 - t1, where both t2 and t1 are greater than 0. Optionally, the target can be a person or an animal located in the transmission optical path of the optical signal emitted by the optical signal transmitting component 20.

[0054] Step 403: Determine the target distance between the target and the projection device according to the transmission speed and transmission duration of the detected optical signal.

[0055] The transmission speed V of the optical signal is pre-stored in the control circuit. After determining the transmission duration of the optical signal, the control circuit can determine the target distance S between the target and the projection device according to the transmission speed V and the transmission duration T of the optical signal. The S = ×V. Since the transmission speed of the optical signal is a fixed value, the length of the target distance is positively correlated with the magnitude of the transmission duration. That is, the longer the transmission duration, the longer the target distance; the smaller the transmission duration, the shorter the target distance.

[0056] Step 404: Determine the target reception field of view angle corresponding to the target distance range in which the target distance is located from the correspondence between the distance range and the reception field of view angle.

[0057] The correspondence between the distance range and the reception field of view angle is pre-stored in the control circuit. After determining the target distance between the target and the projection device, the control circuit can determine the target distance range in which the target distance is located, and determine the target reception field of view angle corresponding to the target distance range from the correspondence between the distance range and the reception field of view angle. The magnitude of the target reception field of view angle is negatively correlated with the length of the target distance, that is, the longer the target distance, the smaller the target reception field of view angle; the shorter the target distance, the larger the target reception field of view angle.

[0058] For example, assuming that the correspondence between the distance range and the receiving field of view angle is shown in Table 1, if the target distance is 0.7 meters (m), this target distance is within the target distance range (0, 0.7m], that is, this target distance range is greater than 0 and less than or equal to 0.7m. From Table 1, it is determined that the target receiving field of view angle corresponding to the target distance range (0, 0.7m] is 30 degrees. If the target distance is 1, this target distance is within the target distance range (0.7m, 1m], that is, this target distance range is greater than 0.7 and less than or equal to 1m. From Table 1, it is determined that the target receiving field of view angle corresponding to the target distance range (0.7m, 1m] is 25 degrees. If the target distance is 1.3m, this target distance is within the target distance range (1m, 1.3m], that is, this target distance range is greater than 1 and less than or equal to 1.3m. From Table 1, it is determined that the target receiving field of view angle corresponding to the target distance range (1m, 1.3m] is 15 degrees.

[0059] Table 1

[0060] Distance range Receiving field of view (0，0.7m] 30 degrees (0.7 m, 1 m] 25 degrees (1 m, 1.3 m] 15 degrees

[0061] Figure 8 It is a schematic diagram of the target receiving field of view angle corresponding to a target distance provided by an embodiment of the present disclosure. As Figure 8 shown, when the target distance is D1, the control circuit can determine, from the correspondence between the distance range and the receiving field of view angle, the target receiving field of view angle ɑ1 corresponding to the target distance range where the target distance is located. When the target distance is D2, the control circuit can determine, from the correspondence between the distance range and the receiving field of view angle, the target receiving field of view angle ɑ0 corresponding to the target distance range where the target distance is located. It can be Figure 8 seen that this target distance D1 is less than the target distance D2, and the target receiving field of view angle ɑ1 corresponding to this target distance D1 is greater than the target receiving field of view angle ɑ0 corresponding to the target distance D2.

[0062] In the embodiment of the present disclosure, in order to achieve effective detection of the target object, the receiving field of view angle FOV of the optical signal receiving component needs to satisfy: FOV = B × . Among them, B is the reflectivity of the target object, and the magnitude of this reflectivity is related to the material of the target object. In the embodiment of the present disclosure, this B can be set to a fixed value. F ( d ) is the efficiency function, and its value is positively correlated with the distance d , and this distance d is the distance between the target object and the projection device. f ( I F ) is related to the number of optical signals emitted by the optical signal transmitting component and the number of target photosensors when the receiving field of view angle of the optical signal receiving component is the largest. This f (I F ) The value is a fixed value. The number of optical signals emitted by the optical signal transmitting component is positively correlated with the duty cycle of the laser drive current signal transmitted by the control circuit to the laser drive circuit. The target photosensor is the photosensor among the photosensors in the optical signal receiving component that are in the on state and can be illuminated by the optical signal reflected by the target object.

[0063] Since B and f ( I F ) The determined values are all fixed values. From this formula, it can be seen that in order to achieve effective detection of the target object, the receiving field of view angle of the optical signal receiving component is negatively correlated with the distance. That is, the shorter the distance between the target object and the projection device, the larger the receiving field of view angle of the optical signal receiving component needs to be set. The longer the distance between the target object and the projection device, the smaller the receiving field of view angle of the optical signal receiving component can be set.

[0064] Step 405: Adjust the receiving field of view angle of the optical signal receiving component to the target receiving field of view angle.

[0065] After the control circuit determines the target receiving field of view angle of the optical signal receiving component, it can adjust the field of view angle of the optical signal receiving component to the target receiving field of view angle so that the optical signal receiving component receives the light reflection signal at the target receiving field of view angle. It should be noted that after the projection device is started, the receiving field of view angle of the optical signal receiving component can be the initial receiving field of view angle stored in advance, and the initial receiving field of view angle can be the maximum receiving field of view angle of the optical signal receiving component. The receiving field of view angle of the optical signal receiving component refers to the range within which the optical signal receiving component can detect optical signals, and the larger the receiving field of view angle, the larger the range within which the optical signal receiving component can detect optical signals.

[0066] As an optional implementation manner of the present disclosure, referring to Figure 5 , the projection device may further include a photosensor drive circuit 50 respectively connected to the control circuit 10 and the optical signal receiving component 30. The control circuit can determine the alternative photosensors to be turned on from the corresponding relationship between the receiving field of view angle and the photosensors according to the target receiving field of view angle. And start the alternative photosensors to adjust the receiving field of view angle of the optical signal receiving component to the target receiving field of view angle.

[0067] Among them, the number of the alternative photosensors is positively correlated with the size of the target receiving field of view angle. The alternative photosensors are the photosensors in the optical signal receiving component that are in the on state, and the alternative photosensors in the on state can receive the optical signal receiving component reflected by the target object.

[0068] Optionally, the correspondence between the received field of view angle and the photosensor is pre-stored in the control circuit. After determining the target received field of view angle, the control circuit can, based on the target received field of view angle, determine the position of the alternative photosensors to be activated in the optical signal receiving component from the correspondence between the received field of view angle and the photosensor. Subsequently, the control circuit 10 can transmit a first field of view angle signal to the photosensor driving circuit 50. The photosensor driving circuit 50 can, in response to the received first field of view angle signal, provide drive current to the alternative photosensors to activate the alternative photosensors, so as to adjust the received field of view angle of the optical signal receiving component to the target received field of view angle.

[0069] Optionally, the photosensor driving circuit 50 can, in response to the received first field of view angle signal, select one or more rows of photosensors in the optical signal receiving component to activate starting from the middle row of the optical signal receiving component row by row.

[0070] Alternatively, the photosensor driving circuit 50 can, in response to the received first field of view angle signal, select one or more columns of photosensors in the optical signal receiving component to activate starting from the middle column of the optical signal receiving component column by column.

[0071] Alternatively, the photosensor driving circuit 50 can, in response to the received first field of view angle signal, determine a circular area with the center of the optical signal receiving component as the center point, and activate the photosensors within the circular area.

[0072] Since the number of the alternative photosensors is positively correlated with the size of the target received field of view angle, that is, the larger the target received field of view angle, the more the number of alternative photosensors, and the smaller the target received field of view angle, the fewer the number of alternative photosensors. Since the control circuit can dynamically adjust the number of photosensors that can be activated in the optical signal receiving component according to the received field of view angle, the power consumption of the projection device is thus reduced.

[0073] Exemplarily, assume M is 6 and N is 12, that is, the optical signal receiving component 30 includes 6×12 photosensors. Figures 9 to 11 The schematic diagram showing the photosensor switch states corresponding to different received field of view angles is shown. Among them, 1 indicates that the photosensor is in the activated state, and 0 indicates that the photosensor is in the deactivated state.

[0074] Refer to Figure 9 , if the target received field of view angle α is 30 degrees, the control circuit can determine the alternative photosensors as the 6×12 photosensors in the optical signal receiving component according to the target received field of view angle of 30 degrees, and can activate the 6×12 alternative photosensors to make the 6×12 alternative photosensors in the activated state.

[0075] Refer to Figure 10, if the target receiving field of view angle α is 25 degrees, the control circuit determines that the alternative photosensors corresponding to the target receiving field of view angle of 25 degrees are the photosensors in the second to fifth rows of the optical signal receiving component. The control circuit can activate the alternative photosensors to make them in the on state, and the photosensors in the remaining rows of the optical signal receiving component are in the off state.

[0076] Reference Figure 11 , if the target receiving field of view angle α is 15 degrees, the control circuit can determine that the alternative photosensors corresponding to the target receiving field of view angle of 15 degrees are the photosensors in the third and fourth rows of the optical signal receiving component. Thus, the control circuit can activate the alternative photosensors to make them in the on state, and the photosensors in the remaining rows of the optical signal receiving component are in the off state.

[0077] As another alternative implementation of the present disclosure, reference Figure 6 and FIG. 8, the projection device may further include an aperture 60 and an aperture driving circuit 70. The aperture driving circuit 70 is respectively connected to the aperture 60 and the control circuit 10. The aperture 60 is located on the side of the optical signal receiving component 30 away from the projection screen 04. The shape of the aperture 60 may be circular or rectangular.

[0078] In the embodiment of the present disclosure, in step 401, after receiving the start instruction sent by the multimedia control component 40, the control circuit may also, in response to the start instruction, send a second field of view angle signal to the optical signal receiving component to control all the photosensors in the optical signal receiving component to be turned on, so that all the photosensors in the optical signal receiving component are in the on state. After determining the target receiving field of view angle, the control circuit may adjust the light input amount of the aperture according to the target receiving field of view angle to adjust the field of view angle of the optical signal receiving component to the target receiving field of view angle.

[0079] Optionally, reference Figure 6 , the control circuit 10 may, in response to the start instruction, send a second field of view angle signal to the optical signal receiving component 30 to control all the photosensors in the optical signal receiving component 30 to be turned on. After determining the target receiving field of view angle, the control circuit 10 may transmit an aperture driving current signal to the aperture driving circuit 70 according to the target receiving field of view angle. The aperture driving circuit 70 may, in response to the aperture driving current signal, provide an aperture driving current to the aperture 60. The aperture 60 may adjust the light input amount of the aperture 60 under the drive of the aperture driving current to adjust the receiving field of view angle of the optical signal receiving component to the target receiving field of view angle.

[0080] Among them, the duty cycle of the aperture drive current signal is positively correlated with the size of the target receiving field of view angle, the magnitude of the aperture drive current is positively correlated with the duty cycle of the aperture drive current signal, and the magnitude of the light incident amount is positively correlated with the magnitude of the aperture drive current. That is, the magnitude of the light incident amount is positively correlated with the size of the target receiving field of view angle. The larger the target receiving field of view angle, the larger the light incident amount of the aperture, and correspondingly, more photosensors in the light signal receiving component can receive the light signal reflected by the target object.

[0081] In the embodiment of the present disclosure, since multiple photosensors included in the light signal receiving component are all in an on state, the receiving field of view angle of the light signal receiving component can be adjusted by adjusting the size of the aperture, thereby adjusting the photosensors in the multiple photosensors that can receive the light signal reflected by the target object.

[0082] For example, assume that the shape of the aperture is rectangular, M is 6, and N is 12, that is, the light signal receiving component 30 includes 6×12 photosensors. If the target receiving field of view angle is 30°, the control circuit can adjust the light incident amount of the aperture according to the target receiving field of view angle, so that all 6×12 photosensors included in the light signal receiving component 30 can receive the light signal reflected by the target object. If the target receiving field of view angle is 25 degrees, the control circuit adjusts the light incident amount of the aperture according to the target receiving field of view angle, so that the photosensors in the second row to the fifth row in the light signal receiving component 30 can all receive the light signal reflected by the target object. If the target receiving field of view angle is 15 degrees, the control circuit adjusts the light incident amount of the aperture according to the target receiving field of view angle, so that the photosensors in the third row and the fourth row in the light signal receiving component can all receive the light signal reflected by the target object.

[0083] Optionally, the aperture is continuously opened or closed under the drive of the aperture drive current, so as to adjust the size of the light incident amount of the aperture. The size of the light incident amount of the aperture is positively correlated with the number of opening times of the aperture per unit time. That is, the larger the light incident amount of the aperture, the more the number of opening times of the aperture per unit time.

[0084] In the embodiment of the present disclosure, when the control circuit detects that the number of opening times of the aperture per unit time is greater than the number threshold, it can reduce the duty cycle of the aperture drive current signal provided to the aperture drive circuit, thereby reducing the aperture drive current provided by the aperture drive circuit to the aperture, so as to avoid the situation that the aperture is damaged due to too many opening times per unit time. The number threshold is a fixed number pre-stored in the control circuit.

[0085] Optionally, a damping coil is provided inside the aperture, and the damping coil is connected to a current sensor. When the control circuit detects that the electromotive force on the damping coil exceeds the electromotive force threshold, it can determine that the number of times the aperture is opened per unit time exceeds the number threshold, and then reduce the duty cycle of the aperture drive current signal provided to the aperture drive circuit, thereby reducing the aperture drive current provided to the aperture. The damping coil serves to smoothly control the aperture.

[0086] Step 406: Determine the target response level corresponding to the target distance range in which the target distance is located from the correspondence between the distance range and the response level.

[0087] In the embodiment of the present disclosure, the control circuit pre-stores the correspondence between the distance range and the response level. In step 404, after the control circuit determines the target distance range in which the target distance is located, it can also determine the target response level corresponding to the target distance range from the correspondence between the distance range and the response level.

[0088] Exemplarily, assume that the correspondence between the distance range and the response level is shown in Table 2. If the target distance is 0.7 m, the target distance is within the target distance range (0, 0.7 m], and the target response level corresponding to the target distance range (0, 0.7 m] is determined from Table 2 to be 1. If the target distance is 1 m, the target distance is within the target distance range (0.7 m, 1 m], and the target response level corresponding to the target distance range (0.7 m, 1 m] is determined from Table 2 to be 2. If the target distance is 1.3 m, the target distance is within the target distance range (1 m, 1.3 m], and the target response level corresponding to the target distance range (1 m, 1.3 m] is determined from Table 2 to be 3.

[0089] Table 2

[0090] Distance range Response level (0，0.7m] 1 (0.7 m, 1 m] 2 (1 m, 1.3 m] 3

[0091] Step 407: Adjust the brightness of the laser light source according to the target response level.

[0092] The control circuit can pre-store the correspondence between the response level and the brightness. After the control circuit determines the target response level, it can determine the target brightness corresponding to the target response level from the correspondence between the response level and the brightness, and then adjust the brightness of the laser light source to the target brightness, and the target brightness is negatively correlated with the target response level.

[0093] Since the target distance is negatively correlated with the target response level, and the target brightness is negatively correlated with the target response level, that is, the shorter the target distance, the higher the target response level, and the lower the target brightness. Therefore, when the target object is close to the projection device, the brightness of the laser light source can be reduced, thereby improving the reliability of protecting the target object. And the response level can be dynamically adjusted according to the distance, and then the brightness of the laser light source can be dynamically adjusted, improving the flexibility of protecting the target object.

[0094] For example, assuming that the correspondence between the response level and the brightness is shown in Table 3, if the target response level is 1, the target brightness corresponding to the target response level 1 is determined from Table 3 to be 0, and then the brightness of the laser light source can be adjusted to 0. If the target response level is 2, the target brightness corresponding to the target response level 2 is determined from Table 3 to be 50% of the initial brightness, and then the brightness of the laser light source can be adjusted to 50% of the initial brightness. If the target response level is 3, the target brightness corresponding to the target response level 3 is determined from Table 3 to be 80% of the initial brightness, and then the brightness of the laser light source can be adjusted to 80% of the initial brightness. The initial brightness is the brightness when the laser light source emits light normally.

[0095] Table 3

[0096] Response level Brightness 1 0 2 50% of the initial brightness 3 80% of the initial brightness

[0097] In the embodiment of the present disclosure, referring to Figure 1 , the multimedia control component 40 may include a first logic control circuit 401 and a multimedia driving sub-component 402. The first logic control circuit 401 is respectively connected to the control circuit 10 and the multimedia driving sub-component 402. The projection device may further include a backlight control component 80, a light source driving component 90, and a laser light source 100. The laser light source 100 is used to emit laser light. The backlight control component 80 may include a display driving circuit 801 and a second logic control circuit 802. The second logic control circuit 802 is connected to the display driving circuit 801 and the multimedia driving sub-component 402 through an inter-integrated circuit (I2C).

[0098] After determining the target brightness, the control circuit 10 can send the target brightness to the multimedia driving sub-component 402 through the first logic control circuit 401, and the multimedia driving sub-component 402 sends the target brightness to the display driving circuit 801 through the second logic control circuit. The display driving circuit 801 adjusts the duty ratio of the light source driving current signal sent to the light source driving component 90 according to the target brightness, thereby adjusting the light source driving current provided by the light source driving component 90 to the laser light source. For example, the display driving circuit 801 can reduce the duty ratio of the light source driving current signal sent to the light source driving component 90, so as to reduce the light source driving current provided by the light source driving component 90 to the laser light source 100, thereby reducing the brightness of the projection screen.

[0099] It should be noted that the sequence of the steps of the field of view angle adjustment method provided by the embodiments of the present disclosure can be appropriately adjusted, and the steps can also be deleted according to the situation. For example, steps 406 and 407 can be deleted according to the situation. Any method of change that can be easily thought of by any person skilled in the art within the technical scope disclosed by the present disclosure should be covered within the protection scope of the present disclosure, so it will not be elaborated here.

[0100] In summary, the embodiments of the present disclosure provide a method for adjusting the field of view angle. The adjustment method can adjust the receiving field of view angle of the optical signal receiving component according to the target distance between the target object and the projection device. Since the size of the adjusted receiving field of view angle is negatively correlated with the length of the target distance, when the target object is relatively close to the projection device, the larger receiving field of view angle can increase the detection range of the optical signal receiving component, making the detection range of the target object more comprehensive, thereby improving the reliability of the detection of the target object. And because the receiving field of view angle of the optical signal receiving component can be dynamically adjusted according to the distance, the flexibility of the detection of the target object is improved. And because the target distance between the projection device and the target object can be detected, the method can detect a stationary person. At the same time, because the brightness of the laser light source can be adjusted according to the target distance, the human eyes are effectively protected.

[0101] The embodiments of the present disclosure also provide a projection device. Refer to Figure 1 and Figure 2 , the projection device may include a control circuit 10, an optical signal transmitting component 20 and an optical signal receiving component 30 disposed on one side of the host of the projection device. The optical signal transmitting component 20 and the optical signal receiving component 30 are disposed on the upper surface or the front side surface of the housing 00 of the projection device, and the optical signal receiving component 30 may include a plurality of photosensors.

[0102] The optical signal transmitting component 20 is configured to emit an optical signal along a preset field of view angle range.

[0103] The optical signal receiving component 30 is configured to receive optical signals reflected by a target in front of or on the side of the projection device.

[0104] Moreover, it further includes a control circuit 10, which is respectively connected to the optical signal transmitting component 20 and the optical signal receiving component 30. The control circuit 10 is configured to determine the target distance between the target and the projection device according to the optical output time value of the optical signal transmitting component 20 and the optical reception time value of the optical signal receiving component 30.

[0105] Moreover, the control circuit is further configured to adjust the reception field angle of the optical signal receiving component according to the target distance, and the size of the reception field angle is negatively correlated with the length of the target distance.

[0106] Moreover, the optical signal receiving component 30 is further configured to receive the optical reflection signal with the adjusted reception field angle.

[0107] Moreover, the control circuit 10 is further configured to adjust the brightness of the laser light source according to the target distance.

[0108] In summary, the embodiments of the present disclosure provide a projection device. In this projection device, the control circuit can adjust the field angle of view of the optical signal receiving component according to the target distance between the target and the projection device. Since the size of the adjusted reception field angle is negatively correlated with the length of the target distance, when the target is relatively close to the projection device, the larger reception field angle can increase the detection range of the optical signal receiving component, making the detection range of the target more comprehensive, thereby improving the reliability of the target detection. And, since the reception field angle of the optical signal receiving component can be dynamically adjusted according to the distance, the flexibility of the target detection is improved. At the same time, since the brightness of the laser light source can be adjusted according to the target distance, the human eyes are effectively protected.

[0109] Optionally, the control circuit 10 is configured to determine the target reception field angle corresponding to the target distance range in which the target distance is located from the correspondence between the distance range and the reception field angle according to the target distance. Adjust the reception field angle of the optical signal receiving component to the target reception field angle.

[0110] Optionally, referring to Figure 5 , this projection device may further include a photosensor driving circuit 50 respectively connected to the control circuit 10 and the optical signal receiving component 30.

[0111] The control circuit 10 is configured to determine the alternative photosensors to be turned on from the correspondence between the reception field angle and the photosensors according to the target reception field angle, and transmit a first field angle signal to the photosensor driving circuit 50, where the number of alternative photosensors is positively correlated with the size of the target reception field angle.

[0112] A photosensor driving circuit 50 is configured to provide a driving current to an alternative photosensor in response to a received first field of view angle signal, turn on the alternative photosensor, so as to adjust a receiving field of view angle of the optical signal receiving component 30 to a target receiving field of view angle.

[0113] Optionally, referring to Figure 6 , the projection device may further include a diaphragm 60 and a diaphragm driving circuit 70. The diaphragm driving circuit 70 is respectively connected to the diaphragm 60 and the control circuit 10. The diaphragm 60 is located on a side of the optical signal receiving component 30 away from the projection screen.

[0114] The control circuit 10 is further configured to:

[0115] In response to a start instruction, send a second field of view angle signal to the optical signal receiving component 30 to control all the photosensors in the optical signal receiving component 30 to be turned on.

[0116] Transmit a diaphragm driving current signal to the diaphragm driving circuit 70 according to the target receiving field of view angle. The duty cycle of the diaphragm driving current signal is positively correlated with the magnitude of the target receiving field of view angle.

[0117] The diaphragm driving circuit 70 is configured to provide a diaphragm driving current to the diaphragm 60 in response to the diaphragm driving current signal. The magnitude of the diaphragm driving current is positively correlated with the duty cycle of the diaphragm driving current signal. In the embodiments of the present disclosure, the diaphragm control circuit mainly has two methods: video control and DC control.

[0118] The diaphragm 60 is configured to adjust the light incident amount of the diaphragm under the drive of the diaphragm driving current, so as to adjust the receiving field of view angle of the optical signal receiving component 30 to the target receiving field of view angle. The magnitude of the light incident amount is positively correlated with the magnitude of the diaphragm driving current.

[0119] Referring to Figure 12 , the control circuit 10 may include a conversion sub-circuit 11, a first comparison sub-circuit 12, a second comparison sub-circuit 13, and a third comparison sub-circuit 14. Each of the comparison sub-circuits is respectively connected to the conversion sub-circuit 11, the diaphragm driving circuit 70, and a negative feedback resistor Rf. The conversion sub-circuit 11 is configured to convert the target distance into an output voltage and transmit the output voltage to the three comparison sub-circuits. Each of the comparison sub-circuits is configured to compare the output voltage with a pre-stored reference voltage and output a diaphragm driving current signal to the diaphragm driving circuit 70, so that the diaphragm driving circuit 70 provides a diaphragm driving current to the diaphragm 60.

[0120] Among them, the reference voltages stored in each comparison circuit can be obtained according to the upper limit value or the lower limit value of different distance ranges. For example, the first reference voltage stored in the first comparison sub-circuit 12 can be obtained according to the upper limit value 0.7m of the distance range (0, 0.7m]. The second reference voltage stored in the second comparison sub-circuit 13 can be obtained according to the upper limit value 1m of the distance range (0.7m, 1m]. The third reference voltage stored in the third comparison circuit 14 can be obtained according to the upper limit value 1.3m of the distance range (1m, 1.3m).

[0121] During the process of the aperture driving circuit 70 providing the aperture driving current to the aperture 60, it is usually necessary to adjust the aperture driving current to the expected value in a short time, so as to adjust the field of view angle of the optical signal receiving component 30 to the target receiving field of view angle. Figure 12 The shown aperture 60, optical signal receiving component 30 and conversion sub-circuit 11 can form a first-order closed-loop system. This first-order closed-loop system has good convergence performance, and can make the aperture driving current of the aperture quickly converge to the expected value, so as to quickly converge the field of view angle of the optical signal receiving component to the target receiving field of view angle, and further make the performance of the system faster and more stable.

[0122] Figure 13 is a schematic diagram of an aperture adjustment process provided by an embodiment of the present disclosure. This schematic diagram includes a first curve, a second curve and a third curve. The first curve represents an underdamped process, the second curve represents a critically damped process, and the third curve represents an overdamped process. In this schematic diagram, the horizontal axis is time, and the vertical axis is the aperture driving current provided to the aperture. Through Figure 13 It can be seen that during the process of the aperture driving circuit providing the aperture driving current to the aperture, compared with the first curve and the third curve, the second curve adjusts the aperture driving current of the aperture to the expected value i in a shorter time T1. During the process of the aperture driving circuit 70 providing the aperture driving current to the aperture 60, the aperture driving current is adjusted to the expected value in a short time, thus achieving critical damping.

[0123] Optionally, referring to Figure 12 , the projection device may further include a first inductor L1, a second inductor L2, a third inductor L3 and a capacitor C. One end of the second inductor L2 is connected to one end of the first inductor L1, and the other end of the second inductor L2 is connected to one end of the capacitor C. One end of the third inductor L3 is connected to the other end of the first inductor L1, and the other end of the third inductor L3 is connected to the other end of the capacitor C. Each comparison circuit is respectively connected to both ends of the capacitor. The second inductor L2 and the third inductor L3 are used for impedance matching.

[0124] After the control circuit 10 reduces the duty cycle of the aperture drive current signal supplied to the aperture drive circuit 70, and thus reduces the aperture drive current supplied to the aperture 60, the control circuit 10 can compare the voltage across the capacitor C with the difference between the voltage supplied by the aperture drive circuit 70 to the aperture 60. If the difference is less than the difference threshold, the control circuit 10 can stop reducing the duty cycle of the aperture drive current signal supplied to the aperture drive circuit 70.

[0125] Optionally, the control circuit 10 is further configured to:

[0126] Determine the target response level corresponding to the target distance range in which the target distance is located from the correspondence between the distance range and the response level.

[0127] Adjust the brightness of the laser light source according to the target response level.

[0128] Optionally, the control circuit 10 is configured to:

[0129] Determine the transmission duration of the optical signal according to the optical output time value of the optical signal transmitting component 20 and the optical reception time value of the optical signal receiving component 30.

[0130] Determine the target distance between the target object and the projection device according to the transmission speed and transmission duration of the optical signal.

[0131] Optionally, referring to Figure 5 and Figure 6 , the optical signal transmitting component 20 may include a laser 22 and a laser driving component 21, and the laser driving component 21 is respectively connected to the laser 22 and the control circuit 10.

[0132] The control circuit 10 is configured to send an enable signal and a laser drive current signal to the laser driving component 21 in response to a start instruction.

[0133] The laser driving component 21 is configured to supply a laser drive current to the laser in response to the enable signal and the laser drive current signal.

[0134] The laser 22 is configured to emit an optical signal under the drive of the laser drive current.

[0135] In the embodiment of the present disclosure, referring to Figure 5 and Figure 6 , the projection device may further include an optical lens 120, a filtering component 110, and a data processing component 140. The optical lens 120 is configured to collimate the detection light emitted by the laser 22. The filtering component 110 is located on the side of the optical signal receiving component 30 away from the projection screen, and is configured to filter out light with a wavelength different from that of the detection light. That is, the filtering component can filter out light reflected by non-human bodies and ambient light.

[0136] The data processing component 140 may include an optical signal analysis sub-component and an optoelectronic conversion sub-component. The optical signal analysis sub-component is configured to determine the number of target photosensors that can be lit after the photosensors in the optical signal receiving component in the on state receive the optical signal reflected by the target object. And send the number to the optoelectronic conversion sub-component, and the optoelectronic conversion sub-component is configured to convert the number into a digital electrical signal and send it to the control circuit, and the control circuit can obtain the number of the target photosensors according to the digital electrical signal.

[0137] In the embodiment of the present disclosure, referring to Figure 1 , the multimedia control component 40 may further include a first memory 403. The first memory 403 may be used to store the image to be projected and displayed. The multimedia driving sub-component 402 may include an application layer 4021, a framework layer 4022, a driving layer 4023, and a boot layer 4024. The application layer 4021, the framework layer 4022, the driving layer 4023, and the boot layer 4024 may send the image to be projected and displayed to the second logic control circuit 802, and then send it to the display driving circuit 801.

[0138] Assume that the laser light source 100 includes a red laser, a green laser component, a blue laser component, and a yellow laser component. A glass lens with a light combining function is provided on the light emitting side of each laser. The display driving circuit 801 may output a red PWM signal R_PWM corresponding to the red laser component based on the red primary color component of the image to be displayed, output a green PWM signal G_PWM corresponding to the green laser component based on the green primary color component of the image to be displayed, output a blue PWM signal B_PWM corresponding to the blue laser component based on the blue primary color component of the image to be displayed, and output a yellow PWM signal Y_PWM corresponding to the yellow laser component based on the yellow primary color component of the image to be displayed. And, the display driving circuit 801 may output an enable signal R_EN corresponding to the red laser component based on the lighting duration of the red laser component in the driving cycle, output an enable signal G_EN corresponding to the green laser component based on the lighting duration of the green laser component in the driving cycle, output an enable signal B_EN corresponding to the blue laser component based on the lighting duration of the blue laser component in the driving cycle. Based on the lighting duration of the yellow laser component in the driving cycle, output an enable signal Y_EN corresponding to the yellow laser component.

[0139] The backlight control component 80 may further include a second memory 803, and the second memory 803 is used to store the base color level values of the pixels in the image to be projected. The display driving circuit 801 is further configured to obtain the base color level values of the pixels in the image to be projected stored in the second memory, and control the light valve to flip according to the base color level values of the pixels in the image to be projected, so as to project and display the image to be projected on the projection screen.

[0140] In summary, the embodiments of the present disclosure provide a projection device. In this projection device, the control circuit can adjust the field of view angle of the optical signal receiving component according to the target distance between the target object and the projection device. Since the size of the adjusted field of view angle is negatively correlated with the length of the target distance, when the target object is relatively close to the projection device, the larger field of view angle can increase the detection range of the optical signal receiving component, making the detection range of the target object more comprehensive, thereby improving the reliability of the target object detection. Moreover, since the field of view angle of the optical signal receiving component can be dynamically adjusted according to the distance, the flexibility of the target object detection is improved. At the same time, since the brightness of the laser light source can be adjusted according to the target distance, the human eyes are effectively protected.

[0141] The above are only the optional embodiments of the present disclosure, and are not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A projection device, characterized in that, The projection device includes: An optical signal transmitting component, configured to transmit signals within a preset field of view angle range; An optical signal receiving component, configured to receive the signals reflected by the target object at the preset field of view angle, and the optical signal receiving component includes a plurality of photosensors; wherein, the optical signal transmitting component and the optical signal receiving component are disposed on one side of the host of the projection device; A control circuit, respectively connected to the optical signal transmitting component and the optical signal receiving component, and the control circuit is configured to determine a target distance between the target object and the projection device according to the signals transmitted by the optical signal transmitting component and the signals received by the optical signal receiving component; Moreover, the control circuit is configured to adjust the receiving field of view angle of the optical signal receiving component to a target receiving field of view angle according to the target distance, and the optical signal receiving component receives the reflected signals at the target receiving field of view angle, and the size of the receiving field of view angle is negatively correlated with the length of the target distance; Moreover, the control circuit is further configured to adjust the brightness of the laser light source according to the target distance; Moreover, the projection device further includes: an aperture and an aperture driving circuit, the aperture driving circuit is respectively connected to the aperture and the control circuit, and the aperture is located on a side of the optical signal receiving component away from the projection screen; The control circuit is further configured to: In response to a start instruction, send a second field of view angle signal to the optical signal receiving component to control all the plurality of photosensors in the optical signal receiving component to be turned on; Transmit an aperture driving current signal to the aperture driving circuit according to the target receiving field of view angle, and the duty ratio of the aperture driving current signal is positively correlated with the size of the target receiving field of view angle; The aperture driving circuit is configured to, in response to the aperture driving current signal, provide an aperture driving current to the aperture, and the magnitude of the aperture driving current is positively correlated with the duty ratio of the aperture driving current signal; The aperture is configured to adjust the light incident amount of the aperture under the drive of the aperture driving current, so as to adjust the receiving field of view angle of the optical signal receiving component to the target receiving field of view angle, and the size of the light incident amount is positively correlated with the magnitude of the aperture driving current.

2. The projection device according to claim 1, wherein, The control circuit is configured to determine the target receiving field of view angle corresponding to the target distance range in which the target distance is located from the correspondence between the distance range and the receiving field of view angle according to the target distance.

3. The projection device according to claim 2, characterized in that, The projection device further includes: a photosensor driving circuit respectively connected to the control circuit and the optical signal receiving component; The control circuit is configured to determine the alternative photosensors to be turned on from the correspondence between the receiving field of view angle and the photosensors according to the target receiving field of view angle, and transmit a first field of view angle signal to the photosensor driving circuit, wherein the number of the alternative photosensors is positively correlated with the size of the target receiving field of view angle; The photosensor driving circuit is configured to, in response to the received first field of view angle signal, provide a driving current to the alternative photosensors to turn on the alternative photosensors, so as to adjust the receiving field of view angle of the optical signal receiving component to the target receiving field of view angle.

4. The projection device according to any one of claims 1 to 3, characterized in that The control circuit is further configured to: Determine the target response level corresponding to the target distance range in which the target distance is located from the corresponding relationship between the distance range and the response level; Adjust the brightness of the projection screen according to the target response level.

5. The projection device according to any one of claims 1 to 3, characterized in that, The control circuit is configured to: Determine the transmission duration of the optical signal according to the optical output time value of the optical signal transmitting component and the optical reception time value of the optical signal receiving component; Determine the target distance between the target object and the projection device according to the transmission speed of the optical signal and the transmission duration.

6. The projection device according to any one of claims 1 to 3, wherein the optical signal transmitting component and the optical signal receiving component are disposed on the upper surface or the front side surface of the housing of the projection device.

7. A field of view adjustment method, characterized in that, The method is applied to a control circuit of a projection device, and the projection device further includes: an optical signal transmitting component and an optical signal receiving component, wherein the optical signal transmitting component and the optical signal receiving component are disposed on one side of the host of the projection device, and the optical signal receiving component includes a plurality of photosensors; and, the projection device further includes: an aperture and an aperture driving circuit, the aperture driving circuit is respectively connected to the aperture and the control circuit, and the aperture is located on a side of the optical signal receiving component away from the projection screen; the control circuit is respectively connected to the optical signal transmitting component and the optical signal receiving component, and the method includes: Determine the target distance between the target object and the projection device according to the signal transmitted by the optical signal transmitting component and the signal received by the optical signal receiving component; According to the target distance, adjust the reception field angle of the optical signal receiving component to a target reception field angle, so that the optical signal receiving component receives the reflected signal at the target reception field angle, and the size of the reception field angle is negatively correlated with the length of the target distance, wherein adjusting the reception field angle of the optical signal receiving component to the target reception field angle specifically includes: Transmit an aperture drive current signal to the aperture drive circuit according to the target reception field angle, and the duty ratio of the aperture drive current signal is positively correlated with the size of the target reception field angle; The aperture adjusts the light incident amount of the aperture under the drive of the aperture drive current to adjust the reception field angle of the optical signal receiving component to the target reception field angle; Adjust the brightness of the laser light source according to the target distance.

8. The method according to claim 7, characterized in that The adjusting the reception field angle of the optical signal receiving component according to the target distance includes: Determine the target reception field angle corresponding to the target distance range in which the target distance is located from the corresponding relationship between the distance range and the reception field angle according to the target distance.

9. The method according to claim 7 or 8, characterized in that, The adjusting the brightness of the laser light source according to the target distance includes: Determine the target response level corresponding to the target distance range in which the target distance is located from the corresponding relationship between the distance range and the response level; Adjust the brightness of the laser light source according to the target response level.

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