Laser projection device and its control method

Abstract

The present application discloses a laser projection device and a control method thereof, belonging to the field of projection display. When the control component in the laser projection device detects that the intensity value of the detected optical signal reflected by the target object is relatively large, it can determine that there is a target object at the first light outlet, and the distance between the target object and the first light outlet is relatively short. Then the control component can reduce the brightness of the laser projection light source. Thereby, it is possible to avoid the situation that the volatiles generated by the target object placed at the first light outlet under the irradiation of high-energy laser damage the projection lens, ensuring the reliability of the projection lens. At the same time, it is avoided that the target object placed at the first light outlet is burned.

Description

Technical Field

[0001] The present disclosure relates to the field of projection display, and particularly to a laser projection device and a control method thereof. Background Art

[0002] Currently, a laser projection device may include a laser projection light source and a projection lens. The laser projection light source is used to emit a laser beam. The projection lens is used to project the laser beam through the light exit of the laser projection device onto a projection screen to achieve projection display.

[0003] However, since the energy of the laser emitted by the laser projection device is relatively high, if a user places an item such as a remote control or a mouse at the light exit of the laser projection device, the volatiles generated by the item under the irradiation of the high-energy laser may damage the projection lens. Summary of the Invention

[0004] Embodiments of the present disclosure provide a laser projection device and a control method thereof, which can solve the problem in the related art that the volatiles generated by an item placed at the light exit of the laser projection device under the irradiation of the high-energy laser may damage the projection lens. The technical solution is as follows:

[0005] On the one hand, a laser projection device is provided. The laser projection device includes: a housing, a control component, a laser projection light source, a light valve, a projection lens, and an optical signal detector located inside the housing; wherein, the housing has a first light exit;

[0006] The laser projection light source is used to emit an illumination beam;

[0007] The light valve is used to modulate the illumination beam into the projection beam;

[0008] The projection lens is used to transmit and image the projection beam through the first light exit;

[0009] The optical signal detector is connected to the control component. The optical signal detector is used to emit a detection optical signal to the outside of the housing, receive the detection optical signal reflected by a target object, and determine the intensity value of the detection optical signal reflected by the target object;

[0010] The control component is further connected to the laser projection light source. The control component is used to adjust the brightness of the laser projection light source according to the intensity value, and the adjusted brightness of the laser projection light source is negatively correlated with the intensity value.

[0011] On the other hand, a control method for a laser projection device is provided, which is applied to a control component in the laser projection device. The laser projection device further includes: a housing, a laser projection light source located inside the housing, and an optical signal detector. The control component is located inside the housing; the control component is respectively connected to the optical signal detector and the laser projection light source; the method includes:

[0012] Obtaining the intensity value of the detected optical signal;

[0013] Adjusting the brightness of the laser projection light source according to the intensity value, and the adjusted brightness of the laser projection light source is negatively correlated with the intensity value;

[0014] Wherein, the intensity value of the detected optical signal is determined by the optical signal detector when emitting the detected optical signal and according to the detected optical signal reflected by the target object received.

[0015] In another aspect, a laser projection device is provided, including: a memory, a processor, and a computer program stored on the memory. When the processor executes the computer program, the steps executed by the control component in the control method of the laser projection device described in the above aspect are implemented.

[0016] In still another aspect, a computer-readable storage medium is provided. Instructions are stored in the computer-readable storage medium. When the instructions are executed by the processor, the steps executed by the control component in the control method of the laser projection device described in the above aspect are implemented.

[0017] In still another aspect, a computer program product including instructions is provided. When the computer program product runs on the computer, the computer is caused to execute the steps executed by the control component in the control method of the laser projection device described in the above aspect.

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

[0019] The embodiments of the present disclosure provide a laser projection device and its control method. When the control component detects that the intensity value of the detected optical signal reflected by the target object is relatively large, it can determine that there is a target object at the first light outlet, and the distance between the target object and the first light outlet is relatively short. Then the control component can reduce the brightness of the laser projection light source. Thereby, the situation that the volatiles generated by the target object placed at the first light outlet under the irradiation of high-energy laser damage the projection lens is avoided, ensuring the reliability of the projection lens. At the same time, the target object placed at the first light outlet is avoided from being burned. Description of the Drawings

[0020] 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 It is a schematic structural diagram of a laser projection device provided by an embodiment of the present disclosure;

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

[0023] Figure 3 It is a schematic structural diagram of yet another laser projection device provided by an embodiment of the present disclosure;

[0024] Figure 4 It is a schematic structural diagram of still another laser projection device provided by an embodiment of the present disclosure;

[0025] Figure 5 It is a schematic diagram of the transmittance of an infrared light filter for optical signals of different wavelengths provided by an embodiment of the present disclosure;

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

[0027] Figure 7 It is a schematic structural diagram of another laser projection device provided by an embodiment of the present disclosure;

[0028] Figure 8 It is a schematic structural diagram of yet another laser projection device provided by an embodiment of the present disclosure;

[0029] Figure 9 It is a cross-sectional view of a laser projection device provided by an embodiment of the present disclosure;

[0030] Figure 10 It is a schematic structural diagram of another laser projection device provided by an embodiment of the present disclosure;

[0031] Figure 11 It is a schematic structural diagram of yet another laser projection device provided by an embodiment of the present disclosure;

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

[0033] Figure 13 It is a schematic structural diagram of another laser projection device provided by an embodiment of the present disclosure;

[0034] Figure 14 It is a schematic structural diagram of another laser projection device provided by an embodiment of the present disclosure;

[0035] Figure 15 It is a flowchart of a control method for a laser projection device provided by an embodiment of the present disclosure;

[0036] Figure 16 It is a flowchart of another control method for a laser projection device provided by an embodiment of the present disclosure. Specific embodiments

[0037] To make the objectives, technical solutions, and advantages of the present disclosure clearer, the following will further describe in detail the embodiments of the present disclosure with reference to the accompanying drawings.

[0038] Figure 1 It is a schematic structural diagram of a laser projection device provided by an embodiment of the present disclosure. Figure 2 It is a schematic structural diagram of another laser projection device provided by an embodiment of the present disclosure. As Figure 1 and Figure 2 shown, the laser projection device may include a housing 00, a control component 10, a laser projection light source 20, a light valve 30, a projection lens 40, and an optical signal detector 50 located inside the housing 00. Among them, referring to Figure 1 , the housing 00 has a first light outlet 001.

[0039] Optionally, the laser projection light source 20 is used to emit an illumination beam. The laser projection light source 20 may include one or more of a blue laser projection light source, a red laser projection light source, and a green laser projection light source. If the laser projection light source 20 is a blue laser projection light source, the laser projection light source 20 is used to emit a blue illumination beam.

[0040] The light valve 30 is used to modulate the illumination beam emitted by the laser projection light source 20 into a projection beam and transmit it to the projection lens 40. The projection lens 40 is used to transmit the image beam through the first light outlet 001 to a projection screen 002 to realize image display.

[0041] Referring to Figure 2 , the optical signal detector 50 is connected to the control component 10. The optical signal detector 50 is used to emit a detection optical signal, receive the detection optical signal reflected by a target object, and determine the intensity value of the detection optical signal reflected by the target object.

[0042] The control component 10 is also connected to the laser projection light source 20. The control component 10 is used to adjust the brightness of the laser projection light source 20 according to the intensity value.

[0043] In the embodiments of the present disclosure, the target object may at least include internal components located within the housing 00, and the internal components can reflect relatively weak detected optical signals. The target object may further include an external object located outside the housing 00 and within the detection range of the optical signal detector 50. For example, the external object may be a remote control, a mouse, a mobile phone, or a person, etc. Among them, the detection range of the optical signal detector 50 and the range of the image light beam transmitted through the first light outlet 001 may overlap or may not overlap. The detection range of the optical signal detector 50 includes the range of the detected optical signal emitted by the optical signal detector 50 and the range of the detected optical signal that can be received and reflected by the target object.

[0044] The brightness of the adjusted laser projection light source 20 is negatively correlated with the intensity value. That is, the larger the intensity value, the lower the brightness of the adjusted laser projection light source 20, and the smaller the intensity value, the higher the brightness of the adjusted laser projection light source 20.

[0045] And the intensity value is negatively correlated with the distance between the target object and the optical signal detector 50. That is, the shorter the distance between the target object and the optical signal detector 50, the larger the intensity value, and the longer the distance between the target object and the optical signal detector 50, the smaller the intensity value.

[0046] In the embodiments of the present disclosure, the distance between the orthographic projection of the optical signal detector 50 on the housing 00 and the first light outlet 001 is relatively close. Therefore, when the target object is located at the first light outlet 001 and the distance between the target object and the first light outlet 001 is relatively close, the intensity value of the detected optical signal reflected by the target object received by the optical signal detector 50 is relatively large. Then, when the control component 10 detects that the intensity value of the detected optical signal reflected by the target object is relatively large, it can determine that there is a target object at the first light outlet 001 and the distance between the target object and the optical signal detector 50 is relatively short. Then the control component 10 can reduce the brightness of the laser projection light source 20, thereby avoiding the situation that the volatiles generated by the target object placed at the first light outlet 001 under the irradiation of high-energy laser damage the projection lens, ensuring the reliability of the projection lens. At the same time, it avoids burning the target object placed at the first light outlet. When the control component 10 detects that the intensity value of the detected optical signal reflected by the target object is relatively small, it can determine that there is no target object at the first light outlet 001 or the distance between the target object and the first light outlet 001 is relatively far, and then the brightness of the laser projection light source 20 can be increased.

[0047] In summary, the embodiments of the present disclosure provide a laser projection device. When the control component detects that the intensity value of the detected optical signal reflected by the target object is relatively large, it can determine that there is a target object at the first light outlet, and the distance between the target object and the first light outlet is relatively short. Then, the control component can reduce the brightness of the laser projection light source. This can avoid the volatiles generated by the target object placed at the first light outlet under the irradiation of high-energy laser from damaging the projection lens, ensuring the reliability of the projection lens. At the same time, it can avoid burning the target object placed at the first light outlet.

[0048] In the embodiments of the present disclosure, the orthographic projection of the optical signal detector 50 on the housing 00 does not overlap with the first light outlet 001, thereby avoiding the optical signal detector 50 from blocking the illumination beam projected by the projection lens through the first light outlet 001, and thus ensuring the display effect of the image. Optionally, the optical signal detector 40 can be disposed outside the housing, or the optical signal detector 50 can be disposed inside the housing 00. Refer to Figure 1 , the housing 00 further has a second light outlet 003 spaced from the first light outlet 001, and the second light outlet 003 is used for transmitting the detected optical signal. The optical signal detector 20 can transmit the detected optical signal through the second light outlet 003 and can receive the detected optical signal reflected by the target object through the second light outlet 003.

[0049] Optionally, the distance between the first light outlet 001 and the second light outlet 003 is relatively short. The housing 00 can include an upper housing and a lower housing disposed opposite to each other, and the lower housing is in contact with the bearing surface 004 of the housing 00. The bearing surface 004 can be a surface of a TV cabinet. The first light outlet 001 and the second light outlet 003 can both be located on the upper housing.

[0050] Refer to Figure 3 , the optical signal detector 50 can include an infrared light emitter 501, an infrared light receiver 502, and an infrared light processing circuit 503. The infrared light emitter 501 is used for emitting an infrared light signal.

[0051] Optionally, the wavelength of the infrared light signal emitted by the infrared light emitter 501 can be a target wavelength. For example, the range of the target wavelength can be from 860 nanometers (nm) to 1000 nm, and for example, the target wavelength can be 940 nm.

[0052] The infrared light receiver 502 is connected to the infrared light processing circuit 503. The infrared light receiver 502 is used for receiving the infrared light signal reflected by the target object 005 and sending the infrared light signal reflected by the target object 005 to the infrared light processing circuit 503.

[0053] The infrared light processing circuit 503 is connected to the control component 10, and the infrared light processing circuit 503 is used to determine a first intensity value of the infrared light signal reflected by the target object 005.

[0054] Optionally, the infrared light processing circuit 503 may convert the infrared light signal reflected by the target object 005 into a digital signal and determine a first intensity value of the digital signal.

[0055] Optionally, when the control component 10 needs to obtain the first intensity value, it may send a first acquisition instruction to the infrared light processing circuit 503. After receiving the first acquisition instruction, the infrared light processing circuit 503 sends the first intensity value of the obtained infrared light signal to the control component 10. Optionally, the control component 10 may send the first acquisition instruction to the infrared light processing circuit 503 in real time or periodically.

[0056] Alternatively, after determining the first intensity value, the infrared light processing circuit 503 may directly send the first intensity value to the control component 10. Optionally, the infrared light processing circuit 503 may send the determined first intensity value to the control component 10 in real time or periodically.

[0057] Reference Figure 4 Furthermore, the laser projection device may further include an infrared light filter 60. The infrared light filter 60 is located on the light-emitting side of the infrared light emitter 501 and is used to transmit the infrared light signal emitted by the infrared light emitter 501 and the infrared light signal reflected by the target object 005.

[0058] Optionally, if the optical signal detector 50 can be disposed inside the housing 00, the infrared light filter 60 is located on the side of the infrared light emitter 501 and the infrared light receiver 502 close to the second light outlet 003.

[0059] The infrared light signal emitted by the infrared light emitter 501 passes through the infrared light filter 60 and is transmitted to the outside of the housing 00 through the second light outlet 003. The infrared light signal reflected by the target object 005 is transmitted to the infrared light receiver 502 through the infrared light filter 60.

[0060] In the embodiments of the present disclosure, the infrared light filter 60 has a high transmittance for the infrared light signal of the target wavelength emitted by the infrared light emitter 501 and a low transmittance for light signals of other wavelengths except the target wavelength. Therefore, the infrared light filter 60 can effectively filter out ambient light from the outside, reduce the probability that the infrared light receiver 502 receives ambient light from the outside, and thus ensure the accuracy of the first intensity value determined by the infrared light processing circuit 503.

[0061] Figure 5 It is a schematic diagram of the transmittance of an infrared light filter provided by an embodiment of the present disclosure for optical signals of different wavelengths. As Figure 5 shown, the abscissa in this schematic diagram represents the wavelength of the optical signal. The ordinate in this schematic diagram represents the transmittance of the infrared light filter for the optical signal. The optical signal includes a visible light signal and a non-visible light signal.

[0062] Referring to Figure 5 it can be seen that for the infrared light signal with a wavelength range of 860 nm to 1000 nm, the transmittance of the infrared light filter 60 is greater than 85%. For the visible light signal with a wavelength of 420 nm to 660 nm, the transmittance of the infrared light filter 60 is between 10% and 20%. It can be seen that the infrared light filter 60 has a high transmittance for the infrared light signal with a wavelength range of 860 nm to 1000 nm and a low transmittance for optical signals of other wavelengths.

[0063] Referring to Figure 6 , Figure 7 and Figure 8 , the laser projection device may further include a circuit board 70, a fixing piece 80, and a fixing rod 90. The board surface of the circuit board 70 and the infrared light filter 60 are both parallel to the bearing surface 004 of the housing 00.

[0064] The circuit board 70 is used to carry the optical signal detector 50, and the circuit board 70 is located on the side of the optical signal detector 50 away from the infrared light filter 60. Optionally, the optical signal detector 50 may be fixed on the circuit board 70.

[0065] The fixing piece 80 is respectively connected to the circuit board 70 and the housing 00, and the fixing piece 80 is located on the side of the circuit board 70 away from the optical signal detector 50, thereby fixing the circuit board 70 on the housing 00.

[0066] In an embodiment of the present disclosure, the laser projection device may further include a first fixing column 91 and a second fixing column 92. The fixing piece 80 is connected to the circuit board 70 through the first fixing column 91. The fixing piece 80 is connected to the housing 00 through the second fixing column 92.

[0067] Referring to Figure 6 and Figure 8, a first threaded hole 701 is provided on the circuit board 70, a second threaded hole 702 is provided on the housing 00, a third threaded hole 703 and a fourth threaded hole 704 are provided on the fixing plate 80. The first fixing post 91 passes through the third threaded hole 703 and is connected to the first threaded hole 701 on the circuit board 70, thereby realizing the connection between the fixing plate 80 and the circuit board 70. The second fixing post 92 passes through the fourth threaded hole 704 and is connected to the second threaded hole 702 on the housing 00, thereby realizing the connection between the fixing plate 80 and the housing 00.

[0068] Optionally, the laser projection device may include a plurality of first fixing posts 91 and second fixing posts 92. A plurality of first threaded holes 701 are provided on the circuit board 70, a plurality of second threaded holes 702 are provided on the housing 00, and a plurality of third threaded holes 703 and a plurality of fourth threaded holes 704 may be provided on the fixing plate 80. Each first fixing post 91 passes through a third threaded hole 703 and is connected to the corresponding first threaded hole 701 on the circuit board 70, thereby improving the reliability of the connection between the fixing plate 80 and the circuit board 70. Each second fixing post 92 passes through a fourth threaded hole 704 and is connected to the corresponding second threaded hole 702 on the housing 00, thereby improving the reliability of the connection between the fixing plate 80 and the housing 00.

[0069] In the embodiments of the present disclosure, other methods may also be adopted to connect the fixing plate to the housing and the circuit board. The embodiments of the present disclosure do not limit the connection method between the fixing plate and the housing and the circuit board.

[0070] Reference Figure 6 , the infrared light filter 60 is connected to the circuit board 70 through the fixing rod 90. Optionally, threads may be provided at both ends of the fixing rod 90, and threaded holes may be provided on both the circuit board 70 and the infrared light filter 60. One end of the fixing rod 90 is connected to the threaded hole on the infrared light filter 60, and the other end is connected to the threaded hole on the circuit board 70.

[0071] If the laser projection device may include a plurality of fixing rods 90, the infrared light filter 60 is connected to the circuit board 70 through the plurality of fixing rods 90, thereby improving the reliability of the connection between the infrared light filter 60 and the circuit board 70.

[0072] Optionally, threads may be provided at both ends of each fixing rod 90, and threaded holes corresponding to each fixing rod 90 may be provided on both the circuit board 70 and the infrared light filter 60. One end of each fixing rod 90 is connected to the corresponding threaded hole on the infrared light filter 60, and the other end is connected to the corresponding threaded hole on the circuit board 70. The embodiments of the present disclosure do not limit the connection method of the infrared light filter 60 to the circuit board 70 through the fixing rod 90, as long as the infrared light filter 60 can be connected to the circuit board 70 through the fixing rod 90.

[0073] Among them, the orthographic projection of the infrared light filter 60 on the housing 00, the orthographic projection of the circuit board 70 on the housing 00, and the orthographic projection of the fixing piece 80 on the housing 00 do not overlap with the first light outlet 001. This avoids the infrared light filter 60, the circuit board 70, and the fixing piece 80 from blocking the illumination light beam projected by the projection lens through the first light outlet 001, thereby ensuring the display effect of the image.

[0074] In the embodiment of the present disclosure, since the optical signal detector 50 is located on the circuit board 70, the infrared light filter 60 is connected to the circuit board 70, and the circuit board 70 is fixed to the housing 00 through the fixing piece 80, thereby realizing the fixation of the infrared light filter 60 and the optical signal detector 50 on the housing 00.

[0075] Reference Figure 7 and Figure 9 The laser projection device may further include a foam 93, and the foam 93 is located between the fixing piece 80 and the circuit board 70. Since the fixing piece 80 applies a pressure to the circuit board 70 and the components on the circuit board 70, by providing the foam 93 between the fixing piece 80 and the circuit board 70, the foam 93 can provide an elastic pressure between the fixing piece 80 and the circuit board 70, thereby avoiding damage to the components on the circuit board 70.

[0076] Reference Figure 9 and Figure 10 The laser projection device may further include a sheet-shaped infrared light absorber 94. Optionally, the infrared light absorber 94 may be a rubber sleeve.

[0077] The infrared light absorber 94 is located between the optical signal detector 50 and the infrared light filter 60. The infrared light absorber 94 is provided with a first through hole 940 and a second through hole 941. One end of the infrared light emitter 501 close to the infrared light filter 60 is located in the first through hole 940, and one end of the infrared light receiver 502 close to the infrared light filter 60 is located in the second through hole 941.

[0078] By providing the infrared light absorber 94 between the optical signal detector 50 and the infrared light filter 60, the infrared light absorber 94 can absorb the infrared light signal emitted by the infrared light emitter 501 to the infrared light filter 60 and reflected back by the infrared light filter 60. Thereby reducing the infrared light signal reflected by the infrared light filter 60 to the infrared light receiver 502, improving the signal-to-noise ratio, and ensuring the reliability of the determination of the first intensity value.

[0079] Optionally, the thickness of the infrared light absorber 94 is greater than the distance between the infrared light filter 60 and the circuit board 70, thereby ensuring an interference fit between the infrared light filter 60 and the circuit board 70, so as to effectively reduce the infrared light signal reflected by the infrared light filter 60 to the infrared light receiver 502. For example, the distance between the infrared light filter 60 and the circuit board 70 can be 0.8 millimeters (mm), and the thickness of the infrared light absorber 94 can be 1 mm.

[0080] Reference Figure 11 , the optical signal detector 50 may further include a driving circuit 504. The control component 10 is connected to the driving circuit 504, and the control component 10 is configured to send a driving signal to the driving circuit 504. The driving circuit 504 is connected to the infrared light emitter 501, and the driving circuit 504 is configured to provide a driving current to the infrared light emitter 501 in response to the driving signal. The infrared light emitter 501 is configured to emit an infrared light signal under the drive of the driving current. Optionally, the greater the driving current, the greater the brightness of the infrared light signal emitted by the infrared light emitter 501.

[0081] Reference Figure 10 and Figure 12 , the optical signal detector 50 may further include a visible light detector 505. Optionally, reference Figure 9 , one end of the visible light detector 505 close to the infrared light filter 60 is located in the second via 941.

[0082] The visible light detector 505 is configured to receive the visible light signal reflected by the target 005 and determine the second intensity value of the visible light signal. The control component 10 is configured to adjust the brightness of the laser projection light source according to the first intensity value and the second intensity value.

[0083] Optionally, if the control component 10 detects that the first intensity value is greater than the first threshold and the second intensity value is greater than the second threshold, it reduces the brightness of the laser projection light source 20. Wherein, both the first threshold and the second threshold are fixed values pre-stored in the control component 10.

[0084] The visible light signal reflected by the target 005 received by the visible light detector 505 may at least include the visible light signal in the ambient light, and the intensity of the visible light signal in the ambient light is weak. If there is a target 005 at the first light outlet 001, the image light beam transmitted by the projection lens 40 through the first light outlet 001 is reflected by the target 005 to the visible light detector 505, and the image light beam is a visible light signal. Therefore, if there is a target 005 at the first light outlet 001, the visible light signal reflected by the target received by the visible light detector 505 may further include the image light beam.

[0085] In an embodiment of the present disclosure, after the control component 10 obtains the first intensity value and the second intensity value, it may first detect whether the first intensity value is greater than the first threshold. If the first intensity value is less than or equal to the first threshold, the control component 10 may determine that there is no target object 005 at the first light outlet 001, or the distance between the target object 005 and the first light outlet 001 is relatively far, then the control component 10 does not need to reduce the brightness of the laser projection light source 20. If the first intensity value is greater than the first threshold, the control component 10 may continue to detect whether the second intensity value is greater than the second threshold. If the second intensity value is greater than the second threshold, the control component 10 may determine that there is a target object 005 at the first light outlet 001, and the distance between the target object 005 and the first light outlet 001 is relatively close, then the control component 10 may reduce the brightness of the laser projection light source 20. If the second intensity value is less than or equal to the second threshold, the control component 10 may determine that there is no target object 005 at the first light outlet 001, or the distance between the target object 005 and the first light outlet 001 is relatively far, then the control component 10 controls the laser projection light source 20 to emit light with the original brightness. Wherein, the original brightness is the brightness when the projection device emits light normally.

[0086] Optionally, the control component 10 may store the correspondence between the infrared light intensity value, the visible light brightness value, and the brightness. After the control component 10 detects that the first intensity value is greater than the first threshold and the second intensity value is greater than the second threshold, it may determine the target brightness corresponding to the first intensity value and the second intensity value from the correspondence. Then the control component 10 reduces the brightness of the laser projection light source 20 to the target brightness.

[0087] Wherein, in this correspondence, the brightness is negatively correlated with the infrared light intensity value and the visible light intensity value, that is, the greater the infrared light intensity value and the visible light intensity value, the lower the brightness; the smaller the infrared light intensity value and the visible light intensity value, the higher the brightness.

[0088] Exemplarily, if the target brightness corresponding to the first intensity value and the second intensity value determined by the control component 10 from the correspondence is 0, the control component 10 may turn off the laser projection light source 20.

[0089] When the control component 10 needs to obtain the second intensity value, the control component 10 may send a second acquisition instruction to the visible light detector 505. After receiving the second acquisition instruction, the visible light detector 505 sends the second intensity value of the acquired visible light signal to the control component 10. Optionally, the control component 10 may send the second acquisition instruction to the visible light detector 505 in real time, or may send the second acquisition instruction to the visible light detector 505 periodically.

[0090] Alternatively, after determining the second intensity value, the visible light detector 505 can directly send the second intensity value to the control component 10. Optionally, the visible light detector 505 can send the determined second intensity value to the control component 10 in real time or periodically.

[0091] In the embodiments of the present disclosure, if the target object includes internal components located within the housing 00 and external objects located outside the housing 00 and within the detection range of the optical signal detector 50. Then the first intensity value h is the sum of the first target intensity value h1 of the infrared light signal reflected by the external object and the second target intensity value h2 of the infrared light signal reflected by the internal component, that is, the first intensity value h = h1 + h2.

[0092] The first target intensity value h1 satisfies: Wherein, k1 is a constant, I is the drive current sent by the drive circuit 504 to the infrared light emitter 501, P is the duty cycle of the drive signal sent by the control component 10 to the drive circuit 504. B1 is the reflectivity of the external object, and d1 is the distance between the external object and the optical signal detector 50. Optionally, k1 can be a conversion coefficient, and k1 is determined by the characteristics of the optical signal detector 50 itself.

[0093] Since k1 is a constant and during the process of driving the infrared light emitter 501 to emit an infrared light signal, the drive current I and the duty cycle P remain basically unchanged. Therefore, it can be determined from the above formula of the first target intensity value h1 that the first target intensity value h1 is positively correlated with the reflectivity B1 of the external object and negatively correlated with the distance d1 between the external object and the optical signal detector 50.

[0094] That is, the larger the reflectivity B1 of the external object, the larger the first target intensity value h1; the smaller the reflectivity B1 of the external object, the smaller the first target intensity value h1. The longer the distance d1 between the external object and the optical signal detector 50, the smaller the first target intensity value h1; the shorter the distance d1 between the external object and the optical signal detector 50, the larger the first target intensity value h1.

[0095] The second target intensity value h2 satisfies: h2 = k2 × d2 × B2. Wherein, k2 is a constant, d2 is the distance between the infrared light filter 60 and the optical signal detector 50, and B2 is the reflectivity of the infrared light filter 60. Optionally, k2 can be a conversion coefficient, and k2 is determined by the distance between the infrared light filter 60 and the optical signal detector 50 and the reflectivity of the infrared light filter 60.

[0096] Since k2 is a constant, it can be determined from the formula of the second target intensity value h2 above that the second target intensity value h2 is positively correlated with the distance d2 between the infrared light filter 60 and the optical signal detector 50, and is positively correlated with the reflectivity B2 of the infrared light filter. That is, the longer the distance d2 between the infrared light filter 60 and the optical signal detector 50, the larger the second target intensity value h2; the shorter the distance d2 between the infrared light filter 60 and the optical signal detector 50, the smaller the second target intensity value h2. The larger the reflectivity B2 of the infrared light filter 60, the larger the second target intensity value h2; the smaller the reflectivity B2 of the infrared light filter 60, the smaller the second target intensity value h2. Wherein, the distance d2 between the infrared light filter 60 and the optical signal detector 50 can be the distance between the infrared filter 60 and the infrared light emitter, or the distance between the infrared filter 60 and the infrared light receiver.

[0097] Optionally, the distance d2 between the optical signal detector 50 and the infrared light filter 60 can be greater than or equal to 0.4 mm and less than or equal to 1 mm. The reflectivity B2 of the infrared light filter 60 can be greater than or equal to 5% and less than or equal to 15%. The distance d2 and the reflectivity B2 can ensure that the second target intensity value h2 is small, thereby avoiding the situation where the second target intensity value h2 is large, and the first target intensity value h1 is small, while the first intensity value h is greater than the first threshold, thus improving the accuracy and reliability of detecting whether there is an object at the first light outlet 001.

[0098] Since the optical signal detector 50 is fixed on the circuit board 70, and the infrared light filter 60 is connected to the circuit board 70 through the fixing rod 90, the distance d2 between the infrared light filter 60 and the optical signal detector 50, and the reflectivity B2 of the infrared light filter are both fixed values. Therefore, the second target intensity value h2 is a fixed value, that is, the intensity value of the infrared light signal reflected by the internal device that the optical signal detector 50 can receive is a fixed value.

[0099] Since the intensity value of the infrared light signal reflected by the target object 005 received by the optical signal detector 50 is the first intensity value h, and h = h1 + h2, and the second target intensity value h2 is a fixed value, the magnitude of the first intensity value h is substantially determined by the first target intensity value h1. And since the first target intensity value h1 is positively correlated with the reflectivity B1 of the external object and negatively correlated with the distance d1 between the external object and the optical signal detector 50, it can be determined that the first intensity value h is positively correlated with the reflectivity B1 of the external object and negatively correlated with the distance d1 between the external object and the optical signal detector 50.

[0100] That is, the greater the reflectivity B1 of the external object, the greater the first intensity value h; the smaller the reflectivity B1 of the external object, the smaller the first intensity value h. The longer the distance d1 between the external object and the optical signal detector 50, the smaller the first intensity value h; the shorter the distance d1 between the external object and the optical signal detector 50, the greater the first intensity value h.

[0101] In the embodiment of the present disclosure, when the control component 10 determines that the first intensity value h is greater than the first threshold, it further detects whether the second intensity value h2 is greater than the second threshold. And when it is determined that the first intensity value h is greater than the first threshold and the second intensity value h2 is greater than the second threshold, the brightness of the laser projection light source 20 is reduced. This avoids the situation where the reflectivity B1 of the target object 005 is relatively high, and the distance d1 between the target object 005 and the optical signal detector 50 is relatively long, while the first intensity value h is greater than the first threshold. Or the situation where the reflectivity B1 of the target object 005 is relatively small, and the distance d1 between the target object 005 and the optical signal detector 50 is relatively short, while the first intensity value h is less than or equal to the first threshold. By further detecting the second intensity value of the visible light signal reflected by the target object 005 after the control component 10 determines that the first intensity value h is greater than the first threshold. And when it is determined that the first intensity value h is greater than the first threshold and the second intensity value h2 is greater than the second threshold, reducing the brightness of the laser projection light source 20 improves the accuracy and reliability of detecting whether there is a target object at the first light outlet 001.

[0102] Optionally, when the control component 10 determines that the target object 005 is relatively close to the first light outlet 001, it can reduce the brightness of the laser projection light source, thereby improving the reliability of protecting the target object, avoiding the target object being burned due to being close to the first light outlet, and at the same time avoiding the situation where the volatiles generated by the target object under the irradiation of the high-energy laser will damage the projection lens. And because the brightness of the laser projection light source can be dynamically adjusted according to the infrared light intensity value and the visible light intensity value, the flexibility of protecting the target object is improved.

[0103] Reference Figure 13 , the visible light detector 505 may include a visible light receiver 5050, a visible light filter 5051, and a visible light processing circuit 5052. The visible light receiver 5050 is connected to the visible light filter 5051, and the visible light receiver 5050 is configured to receive the visible light signal reflected by the target object 005 and transmit the visible light signal to the visible light filter 5051.

[0104] The visible light filter 5051 is also connected to the visible light processing circuit 5052, and the visible light filter 5051 is configured to perform filtering processing on the visible light signal and transmit the filtered visible light signal to the visible light processing circuit 5052.

[0105] The visible light processing circuit 5052 is also connected to the control component 10. The visible light processing circuit 5052 is configured to determine a second intensity value of the filtered visible light signal and send the second intensity value to the control component 10.

[0106] Optionally, the control component 10 may send a second acquisition instruction to the visible light processing circuit 5052. Alternatively, after determining the second intensity value, the visible light processing circuit 5052 may directly send the second intensity value to the control component 10.

[0107] Reference Figure 14 , the projection device may further include a main board 95, a display board 96, and a light source driving component 97. Among them, a first logic control circuit 951 and a slave control component 952 are provided on the main board 95, and a display driving circuit 961 is provided on the display board 96.

[0108] Among them, the first logic control circuit 951 is respectively connected to the control component 10 and the slave control component 952. The display driving circuit 961 is respectively connected to the slave control component 952 and the light source driving component 97, and the light source driving component 97 is connected to the laser projection light source 20.

[0109] After determining the target brightness corresponding to the first intensity value and the second intensity value, the control component 10 may send the target brightness to the first logic control circuit 951, and the first logic control circuit 951 may send the target brightness to the slave control component 952. Then, the slave control component 952 may send the target brightness to the display driving circuit 961. The display driving circuit 961 may reduce the duty ratio of the current signal provided to the light source driving component 40 according to the target brightness, thereby reducing the magnitude of the driving current provided by the light source driving component 97 to the laser projection light source 20, so as to reduce the brightness of the laser projection light source 20 to the target brightness.

[0110] Reference Figure 14 , the slave control component 952 may include an application layer 9521, a framework layer 9522, a driver layer 9523, and a boot layer 9524. The first logic control circuit 951 may sequentially transmit the target brightness to the boot layer 9524, the driver layer 9523, the framework layer 9522, and the application layer 9521, and transmit it to the display driving circuit 961 through the application layer 9521.

[0111] The laser projection device may further include a first memory 953, a second logic control circuit 962, and a second memory 963. Among them, the first memory 953 is connected to the slave control component 952, and the first memory 953 is used to store the image to be projected and displayed. The second memory 963 is connected to the display driving circuit 961, and the second memory 963 is used to store the base color level values of the pixels in the image to be projected. The display driving circuit 961 is further configured to obtain the base color level values of the pixels in the image to be projected stored in the second memory 963, 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 onto the projection screen.

[0112] Assume that the laser projection light source 20 includes a red laser projection light source, a green laser projection light source, a blue laser projection light source, and a yellow laser projection light source. The display driving circuit 961 may output a red PWM signal R_PWM corresponding to the red laser projection light source 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 projection light source 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 projection light source 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 projection light source based on the yellow primary color component of the image to be displayed. Moreover, the display driving circuit 961 may output an enable signal R_EN corresponding to the red laser projection light source through the second logic control circuit 962 based on the lighting duration of the red laser projection light source within the driving cycle, output an enable signal G_EN corresponding to the green laser projection light source through the second logic control circuit 962 based on the lighting duration of the green laser projection light source within the driving cycle, output an enable signal B_EN corresponding to the blue laser projection light source through the second logic control circuit 962 based on the lighting duration of the blue laser projection light source within the driving cycle, and output an enable signal Y_EN corresponding to the yellow laser projection light source through the second logic control circuit 962 based on the lighting duration of the yellow laser projection light source within the driving cycle.

[0113] In summary, the embodiment of the present disclosure provides a laser projection device. When the control component detects that the intensity value of the detected optical signal reflected by the target object is relatively large, it can determine that there is a target object at the first light outlet, and the distance between the target object and the first light outlet is relatively short. Then the control component can reduce the brightness of the laser projection light source. This avoids the situation that the volatiles generated by the target object placed at the first light outlet under the irradiation of high-energy laser damage the projection lens, ensuring the reliability of the projection lens. At the same time, it avoids burning the target object placed at the first light outlet.

[0114] Figure 15It is a flowchart of a control method for a laser projection device provided by an embodiment of the present disclosure. This control method can be applied to Figures 1 to 4 and Figures 6 to 14 any of the control components 10 in the laser projection devices shown. As Figure 15 shown, this method may include:

[0115] Step 1501: Obtain the intensity value of the detection optical signal.

[0116] Step 1502: Adjust the brightness of the laser projection light source according to the intensity value.

[0117] Among them, the brightness of the adjusted laser projection light source is negatively correlated with the intensity value, and the intensity value of the detection optical signal is determined by the optical signal detector when emitting the detection optical signal and according to the received detection optical signal reflected by the target object.

[0118] For the specific implementation processes of the above steps 1501 and 1502, reference can be made to the above device embodiment, and the embodiments of the present disclosure will not elaborate herein.

[0119] In summary, the embodiments of the present disclosure provide a control method for a laser projection device. When the control component detects that the intensity value of the detection optical signal reflected by the target object is relatively large, it can determine that there is a target object at the first light outlet, and the distance between the target object and the first light outlet is relatively short. Then the control component can reduce the brightness of the laser projection light source. Thereby, it is possible to avoid the situation where the volatiles generated by the target object placed at the first light outlet under the irradiation of high-energy laser damage the projection lens, ensuring the reliability of the projection lens. At the same time, it is possible to avoid burning the target object placed at the first light outlet.

[0120] Figure 16 It is a flowchart of a control method for a laser projection device provided by an embodiment of the present disclosure. This control method can be applied to Figures 1 to 4 and Figures 6 to 14 any of the control components 10 in the laser projection devices shown. As Figure 16 shown, this method may include:

[0121] Step 1601: Obtain the first intensity value of the infrared optical signal.

[0122] Step 1602: Obtain the second intensity value of the visible optical signal.

[0123] Step 1603: Adjust the brightness of the laser projection light source according to the first intensity value and the second intensity value.

[0124] For the specific implementation processes of the above steps 1601 to 1603, reference can be made to the above device embodiment, and the embodiments of the present disclosure will not elaborate herein.

[0125] It should be noted that the sequence of steps of the control method of the laser projection device provided in the embodiments of the present application can be appropriately adjusted, and the steps can also be deleted according to the situation. For example, the above step 1602 can be deleted according to the situation. Any person skilled in the art within the technical scope disclosed in the present application can easily think of a changed method, which should be covered within the protection scope of the present application, so it will not be elaborated here.

[0126] In summary, the embodiments of the present disclosure provide a control method for a laser projection device. When the control component detects that the intensity value of the detected optical signal reflected by the target object is relatively large, it can determine that there is a target object at the first light outlet, and the distance between the target object and the first light outlet is relatively short. Then the control component can reduce the brightness of the laser projection light source. This avoids the situation where the volatile substances generated by the target object placed at the first light outlet under the irradiation of high-energy laser damage the projection lens, ensuring the reliability of the projection lens. At the same time, it avoids burning the target object placed at the first light outlet.

[0127] The embodiments of the present disclosure provide a laser projection device, including: a memory, a processor, and a computer program stored on the memory. When the processor executes the computer program, it implements the steps executed by the control component in the above method embodiments (for example Figure 15 and Figure 16 any one of the illustrated embodiments).

[0128] The embodiments of the present disclosure provide a computer-readable storage medium, in which instructions are stored. When the instructions are executed by the processor, they implement the steps executed by the control component in the above method embodiments (for example Figure 15 and Figure 16 any one of the illustrated embodiments).

[0129] The embodiments of the present disclosure provide a computer program product containing instructions. When the computer program product runs on a computer, it causes the computer to execute the steps executed by the control component in the above method embodiments (for example Figure 15 and Figure 16 any one of the illustrated embodiments).

[0130] In the embodiments of the present disclosure, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance. In the embodiments of the present disclosure, the meaning of the term "plurality" refers to two or more. In the embodiments of the present disclosure, the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone.

[0131] The foregoing are only alternative 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 within the protection scope of the present disclosure.

Claims

1. A laser projection device, characterized in that, The laser projection device includes: a housing, a control component, a laser projection light source, a light valve, a projection lens, and an optical signal detector located inside the housing; wherein, the housing has a first light outlet and a second light outlet spaced from the first light outlet; The laser projection light source is used for emitting an illumination light beam; The light valve is used for modulating the illumination light beam into a projection light beam; The projection lens is used for transmitting and imaging the projection light beam through the first light outlet; The optical signal detector is connected to the control component. The optical signal detector is used for emitting a detection optical signal to the outside of the housing through the second light outlet, receiving the detection optical signal reflected by the target object through the second light outlet, and determining the intensity value of the detection optical signal reflected by the target object. The target object includes internal devices located inside the housing and external objects located outside the housing and within the detection range of the optical signal detector; Wherein, the optical signal detector includes: an infrared light emitter, an infrared light receiver, and an infrared light processing circuit; the infrared light emitter is used for emitting an infrared light signal through the second light outlet; the infrared light receiver is connected to the infrared light processing circuit. The infrared light receiver is used for receiving the infrared light signal reflected by the target object through the second light outlet and sending the infrared light signal reflected by the target object to the infrared light processing circuit; the infrared light processing circuit is connected to the control component. The infrared light processing circuit is used for determining a first intensity value of the infrared light signal reflected by the target object. The first intensity value includes a first target intensity value of the infrared light signal reflected by the external object and a second target intensity value of the infrared light signal reflected by the internal device; Wherein, the laser projection device further includes: an infrared light filter; the infrared light filter is located on the light-emitting side of the infrared light emitter and is used for transmitting the infrared light signal emitted by the infrared light emitter and the infrared light signal reflected by the target object; the distance between the optical signal detector and the infrared light filter is greater than or equal to 0.4 mm and less than or equal to 1 mm, and the reflectivity of the infrared light filter is greater than or equal to 5% and less than or equal to 15% to reduce the second target intensity value; Wherein, the control component is further connected to the laser projection light source. The control component is used for adjusting the brightness of the laser projection light source according to the intensity value of the detection optical signal, and the brightness of the adjusted laser projection light source is negatively correlated with the intensity value of the detection optical signal.

2. The laser projection device according to claim 1, wherein The laser projection device further includes: a circuit board, a fixing piece, and a fixing rod; the board surface of the circuit board and the infrared light filter are both parallel to the bearing surface of the housing; The circuit board is used for carrying the optical signal detector, and the circuit board is located on the side of the optical signal detector away from the infrared light filter; The fixing piece is respectively connected to the circuit board and the housing, and the fixing piece is located on the side of the circuit board away from the optical signal detector; The infrared light filter is connected to the circuit board through the fixed rod; Among them, the orthographic projection of the infrared light filter on the housing, the orthographic projection of the circuit board on the housing, and the orthographic projection of the fixing piece on the housing do not overlap with the first light outlet.

3. The laser projection device according to any one of claims 1 to 2, characterized in that, The optical signal detector further includes: a drive circuit; The control component is connected to the drive circuit, and the control component is configured to send a drive signal to the drive circuit; The drive circuit is connected to the infrared light emitter, and the drive circuit is configured to provide a drive current to the infrared light emitter in response to the drive signal; The infrared light emitter is configured to emit an infrared light signal under the drive of the drive current.

4. The laser projection device according to any one of claims 1 to 3, characterized in that The laser projection device further includes: a sheet-shaped infrared light absorber; the infrared light absorber is located between the optical signal detector and the infrared light filter; The infrared light absorber is provided with a first through hole and a second through hole. One end of the infrared light emitter close to the infrared light filter is located in the first through hole, and one end of the infrared light receiver close to the infrared light filter is located in the second through hole.

5. The laser projection device according to claim 1, wherein The optical signal detector further includes: a visible light detector; The visible light detector is configured to receive the visible light signal reflected by the target and determine a second intensity value of the visible light signal; The control component is configured to adjust the brightness of the laser projection light source according to the first intensity value and the second intensity value.

6. The laser projection device according to claim 5, characterized in that, The visible light detector includes: a visible light receiver, a visible light filter, and a visible light processing circuit; The visible light receiver is connected to the visible light filter. The visible light receiver is configured to receive the visible light signal reflected by the target and transmit the visible light signal to the visible light filter; The visible light filter is further connected to the visible light processing circuit. The visible light filter is configured to perform filtering processing on the visible light signal and transmit the filtered visible light signal to the visible light processing circuit; The visible light processing circuit is further connected to the control component. The visible light processing circuit is configured to determine the second intensity value of the filtered visible light signal and send the second intensity value to the control component.

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