A projection device

Abstract

The present application discloses a projection device, comprising a light source array module, an image processing unit, and a driving unit. The light source array module includes a first light-emitting element array that emits a first primary color light, a second light-emitting element array that emits a second primary color light, and a third light-emitting element array that emits a third primary color light. The first, second, and third light-emitting element arrays are each divided into M×N illumination areas. The image processing unit is configured to divide an image to be projected into M×N image areas and obtain brightness information of the first, second, and third primary colors of light in each image area. The image areas correspond one-to-one to the illumination areas of the light source array module. The driving unit is configured to sequentially drive the first, second, and third light-emitting element arrays based on the brightness information of the first, second, and third primary colors of light in each image area. This simplifies the circuit structure, saves costs, and reduces power consumption.

Description

Technical Field

[0001] The present application belongs to the field of projection display technology, and in particular relates to a projection device. Background Art

[0002] The contrast ratio of projection display technology using a single spatial light modulator is far lower than the resolution of the human eye. This results in a low grayscale, poor layering, and a loss of detail. High dynamic range (HDR) projection systems can effectively increase the contrast and brightness of the projected image, providing rich grayscale information in both bright and dark scenes, significantly improving the quality of the projected image and the audience's viewing experience.

[0003] Currently, one approach to implementing HDR projection systems is to use LCD local dimming technology with LED backlights. This technology employs an LED array as the projector's light source, with each LED responsible for illuminating a specific area. During projection, the intensity of each LED is dynamically controlled based on the brightness of each area of the projected image, achieving high-contrast display and avoiding unnecessary light energy loss. However, implementing local dimming technology as a projector's light source is difficult due to the large number of LEDs in the array, the complex circuitry, and the high cost. Summary of the Invention

[0004] The main technical problem to be solved by the present application is to provide a projection device with a simplified driving circuit, reduced circuit cost and power consumption.

[0005] To solve the above technical problems, the present application adopts a technical solution: providing a projection device including a light source array module, an image processing unit and a driving unit, wherein the light source array module includes a first light-emitting element array that emits a first primary color light, a second light-emitting element array that emits a second primary color light, and a third light-emitting element array that emits a third primary color light, wherein the first light-emitting element array, the second light-emitting element array and the third light-emitting element array are each divided into M×N illumination areas; the image processing unit is used to divide the image to be projected into M×N image areas and obtain brightness information of the first primary color light, the second primary color light and the third primary color light of each image area, wherein the image areas correspond to the illumination areas of the light source array module one-to-one; the driving unit is connected to the first light-emitting element array, the second light-emitting element array, the third light-emitting element array and the image processing unit, and is used to sequentially drive the first light-emitting element array, the second light-emitting element array and the third light-emitting element array according to the brightness information of the first primary color light, the second primary color light and the third primary color light of each image area, and control the light brightness of each illumination area of the first light-emitting element array, the second light-emitting element array and the third light-emitting element array.

[0006] The beneficial effects of the present application are as follows: different from the prior art, the projection device of the embodiment of the present application sequentially drives the first light-emitting element array, the second light-emitting element array and the third light-emitting element array through the driving unit, and controls the luminous brightness of each illumination area of the first light-emitting element array, the second light-emitting element array and the third light-emitting element array, so that the three light-emitting element arrays can be driven by time division multiplexing, the number of driving units can be reduced, the circuit structure can be simplified, the circuit cost can be saved, and the circuit power consumption can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 is a block diagram of an embodiment of the projection device of the present application;

[0008] Figure 2 is a block diagram of another embodiment of the projection device of the present application;

[0009] Figure 3 This is a circuit schematic diagram of an embodiment of a DC-DC driving circuit of a projection device of the present application. DETAILED DESCRIPTION

[0010] In order to make the purpose, technical solutions and effects of this application clearer and more specific, this application is further described in detail below with reference to the accompanying drawings and examples.

[0011] The embodiment of the present application provides a projection device, such as Figure 1 As shown, the light source array module 140, the image processing unit 130 and the driving unit 160, the light source array module 140 includes a first light emitting element array 141 that emits a first primary color light, a second light emitting element array 142 that emits a second primary color light, and a third light emitting element array 143 that emits a third primary color light. The first light emitting element array 141, the second light emitting element array 142 and the third light emitting element array 143 are evenly divided into M×N lighting areas; the image processing unit 130 is used to divide the image to be projected into M ×N image areas, and obtaining brightness information of the first primary color light, the second primary color light and the third primary color light of each image area, wherein the image areas correspond one to one to the illumination areas of the light source array module 140; the driving unit 160 is connected to the first light-emitting element array 141, the second light-emitting element array 142, the third light-emitting element array 143 and the image processing unit 130, and is used to sequentially drive the first light-emitting element array 141, the second light-emitting element array 142 and the third light-emitting element array 143 according to the brightness information of the first primary color light, the second primary color light and the third primary color light of each image area, and control the light-emitting brightness of each illumination area of the first light-emitting element array 141, the second light-emitting element array 142 and the third light-emitting element array 143.

[0012] The projection device of the embodiment of the present application sequentially drives the first light-emitting element array 141, the second light-emitting element array 142 and the third light-emitting element array 143 through the driving unit 160, and controls the luminous brightness of each illumination area of the first light-emitting element array 141, the second light-emitting element array 142 and the third light-emitting element array 143. It can drive the three light-emitting element arrays in a time-division multiplexing manner, which can reduce the number of driving units 160, simplify the circuit structure, save circuit costs, and reduce circuit power consumption.

[0013] Specifically, in the embodiment of the present application, the first primary color is red, the second primary color is blue, and the third primary color is green. The first light-emitting element array 141 emits red light, the second light-emitting element array 142 emits blue light, and the third light-emitting element array 143 emits green light. The first light-emitting element array 141 is composed of a plurality of first light-emitting element arrays 141, the second light-emitting element array 142 is composed of a plurality of second light-emitting element arrays 142, and the third light-emitting element array 143 is composed of a plurality of third light-emitting element arrays 143. The number of first light-emitting elements, second light-emitting elements, and third light-emitting elements is preferably greater than or equal to M×N, where M is greater than or equal to 2 and N is greater than or equal to 2.

[0014] Furthermore, in an embodiment of the present application, the first light-emitting element array 141, the second light-emitting element array 142 and the third light-emitting element array 143 are spatially separated from each other, and the first primary color light emitted by the first light-emitting element array 141, the second primary color light emitted by the second light-emitting element array 142 and the third primary color light emitted by the third light-emitting element array 143 are emitted after being combined by a light-combining device to form the output light of the light source array module 140. When the first primary color light is red light, the second primary color light is blue light, and the third primary color light is green light, the light combining device includes a first dichroic plate and a second dichroic plate. The first dichroic plate can transmit blue light and reflect green light. It is arranged at the intersection of the blue light emitted by the second light-emitting element array 142 and the green light emitted by the third light-emitting element array 143, and is used to combine the blue light and the green light; the second dichroic plate can transmit blue light and green light and reflect red light. It is arranged at the intersection of the combined light of the blue light and the green light emitted by the first dichroic plate and the red light emitted by the first light-emitting element array 141, and is used to combine the red light, blue light and green light.

[0015] Preferably, the driving unit 160 is a current driving unit for driving the light-emitting elements with a current corresponding to the brightness information. By controlling the current of the light-emitting elements in the light source array module 140 to control the brightness of the light-emitting elements, it is suitable for using a spatial light modulator to achieve regional dimming projection display.

[0016] like Figure 2As shown, the projection device of the embodiment of the present application also includes a driving control unit 150, which is connected to the driving unit 160, and the image processing unit 130 is connected to the driving control unit 150; the driving control unit 150 receives brightness information of the first primary color light, the second primary color light and the third primary color light of each image area of the image processing unit 130, and is used to control multiple driving units 160 to drive the first light-emitting element array 141 or the second light-emitting element array 142 or the third light-emitting element array 143; the driving unit 160 is used to drive the first light-emitting element array 141 or the second light-emitting element array 142 or the third light-emitting element array 143.

[0017] Furthermore, the projection device of the embodiment of the present application also includes a power supply circuit 110 and a switch 120. There are three switches 120, namely a first switch 121, a second switch 122 and a third switch 123, wherein the first switch 121 is connected between the power supply circuit 110 and the first light-emitting element array 141; the second switch 122 is connected between the power supply circuit 110 and the second light-emitting element array 142; and the third switch 123 is connected between the power supply circuit 110 and the third light-emitting element array 143; the driving control unit 150 is connected to the first switch 121, the second switch 122 and the third switch 123, and is used to connect the first switch 121 when the control driving unit 160 drives the first light-emitting element array 141, connect the second switch 122 when the control driving unit 160 drives the second light-emitting element array 142, and connect the third switch 123 when the control driving unit 160 drives the third light-emitting element array 143.

[0018] In the embodiment of the present application, the driving unit 160 sequentially controls the connectivity of the first switch 121 , the second switch 122 and the third switch 123 , thereby sequentially driving the first light emitting element array 141 , the second light emitting element array 142 and the third light emitting element array 143 .

[0019] In this embodiment, the light-emitting elements in the light source array module 140 are arranged in M×N order according to the aspect ratio of the picture. The image processing unit 130 is used to receive image information to be projected, divide the image information to be projected into M×N areas according to the arrangement of the light-emitting element array, and generate first primary color brightness information of the first primary color picture frame in each area, third primary color brightness information of the third primary color picture frame in each area, and second primary color brightness information of the second primary color picture frame in each area according to the image information to be projected. The image processing unit 130 receives a frame synchronization signal and, under the control of the frame synchronization signal, sends the first primary color brightness information, the third primary color brightness information, and the second primary color brightness information to the drive control unit 150 in sequence.

[0020] The driving control unit 150 is used to send brightness information to the driving unit 160 in sequence, and drive the first light-emitting element array 141, the second light-emitting element array 142 and the third light-emitting element array 143 in time-division multiplexing by opening and closing the three switches 120, namely the first switch 121, the second switch 122 and the third switch 123, in sequence.

[0021] In this embodiment, the driving unit 160 is a light-emitting element driving chip. Each output end of the light-emitting element driving chip is connected to a first light-emitting element, a second light-emitting element and a third light-emitting element. The three light-emitting elements are driven in sequence in a time-sharing manner within a picture frame period. The picture frame period is divided into three segments. One light-emitting element is lit in each time segment to form a single-primary color picture frame. Finally, through the visual aftereffect of the human eye, the three single-primary color picture frames of red, blue and green are combined into a color picture frame.

[0022] The projection device of the embodiment of the present application uses time-division multiplexing to drive the three light-emitting element arrays 141, 142, and 143. This reduces the number of light-emitting element driver chips to one-third of the original number, simplifies the circuit, and reduces circuit cost and power consumption. The projection device of the embodiment of the present application can adjust the driving current of each light-emitting element, thereby adjusting the brightness of each light-emitting element, meeting the requirements of a regional dimming projection display system. Furthermore, the embodiment of the present application only requires one drive control unit 150, three switches 120, and light-emitting element driver chips, resulting in fewer IO ports in the drive control unit 150 and simpler circuit connections.

[0023] Specifically, in this embodiment, the image processing unit 130 is an FPGA (field programmable gate array), and the driver control unit 150 is a CPLD (complex programmable logic device), which are used to process images and control data transmission. The driver unit 160 in this embodiment is a current control unit based on the TLC5940 chip, a 16-channel sink-type light-emitting element driver chip. The output current of each channel is regulated by a 6-bit binary number. In specific implementation, each brightness value in the brightness information is mapped to a corresponding 6-bit binary number. The CPLD then sequentially inputs these mapped binary numbers into the TLC5940 chip to control the current of each channel. This achieves the purpose of dynamically adjusting the brightness of the corresponding light-emitting element according to the brightness of each area of the projected image, meeting the requirements of regional dimming projection display technology for backlight sources. Each channel of the TLC5940 chip in this embodiment of the present invention is connected to the cathode of one light-emitting element in each of the three light-emitting element arrays. During a frame period, the three light-emitting elements are driven in a time-sharing manner by sequentially opening the first switch 121, the second switch 122, and the third switch 123. This time-division multiplexing method reduces the number of TLC5940 chips required by 2 / 3, simplifies the circuit, and reduces circuit cost and power consumption.

[0024] Specifically, in this embodiment, each switch 120 comprises an NMOS transistor and a PMOS transistor. The control terminals of the NMOS and PMOS transistors are respectively connected to a CPLD. The first terminal of the NMOS transistor is connected to the power supply circuit 110, and the second terminal of the NMOS transistor is connected to the light-emitting element array. The first terminal of the PMOS transistor is connected to the light-emitting element array, and the second terminal of the PMOS transistor is grounded. The CPLD controls the opening or closing of the switch 120 by outputting a control signal, thereby connecting or disconnecting the power supply circuit 110 from the light source array module 140. The power supply circuit 110 is a DC-DC drive circuit. In this embodiment, when a switch 120 needs to be opened, the NMOS transistor is first closed, and then the PMOS transistor is opened. Closing the NMOS transistor first prevents the DC-DC drive circuit from short-circuiting when the PMOS transistor is opened, thereby preventing the NMOS transistor from burning out due to a large current flowing through the NMOS transistor. When a switch 120 needs to be closed, the PMOS transistor is first closed, and then the NMOS transistor is opened. Closing the PMOS transistor and then opening the NMOS transistor can quickly discharge the anode charge of the light-emitting element, thereby improving the speed of the switch 120.

[0025] For the first light emitting element array 141, the second light emitting element array 142 and the third light emitting element array 143, the driving voltage may differ by 1V to 2V, requiring different driving circuits. To solve this problem, the output voltage range of the DC-DC driving circuit in the embodiment of the present application is adjustable between 3.3V and 5V, such as Figure 3The DC-DC drive circuit of the embodiment of the present application includes a DC-DC chip 111 and a digitally controlled potentiometer 112. The output voltage of the DC-DC chip 111 is controlled by the resistance value of the digitally controlled potentiometer 112. The digitally controlled potentiometer 112 is connected to a drive control unit 150. The DC-DC chip 111 is connected to a switch 120. When the drive unit 150 drives the first light-emitting element array 141, the second light-emitting element array 142, and the third light-emitting element array 143, the drive control unit 150 sends control signals to the digitally controlled potentiometer 112 to adjust the resistance value of the digitally controlled potentiometer 112, respectively, so that the DC-DC chip 111 outputs a first output voltage, a second output voltage, and a third output voltage. Specifically, in an embodiment of the present application, a digitally controlled potentiometer 112 with adjustable resistance is connected between the FB pin (voltage adjustment pin) and the SW pin (switch 120 control pin) of the DC-DC chip 111 to achieve adjustable output voltage of the DC-DC drive circuit; the resistance of the digitally controlled potentiometer 112 can be controlled by writing an 8-bit binary number to its SDI pin. In this embodiment, the drive control unit 150, i.e., the CPLD, is connected to the digitally controlled potentiometer 112. When the drive unit 160 needs to drive a light-emitting element array of a certain color, the CPLD only needs to send a corresponding control number to the digitally controlled potentiometer 112 to allow the DC-DC drive circuit to output a corresponding drive voltage. That is, through time division multiplexing, the functions of three DC-DC drive circuits are realized by one DC-DC drive circuit, which simplifies the circuit structure and saves circuit costs.

[0026] Specifically, in this embodiment, the FPGA is connected to the CPLD, the first switch 121 is connected between the DC-DC drive circuit and the first light-emitting element array 141, the second switch 122 is connected between the DC-DC drive circuit and the second light-emitting element array 142, and the third switch 123 is connected between the DC-DC drive circuit and the third light-emitting element array 143; the CPLD is connected to the control ends of the first switch 121, the second switch 122, and the third switch 123 in the switch 120, thereby respectively controlling the three switches 120 to be turned on or off, thereby controlling the DC-DC drive circuit to be connected or disconnected with the three light-emitting element arrays 141, 142, and 143, respectively. The CPLD is connected to the digitally controlled potentiometer of the DC-DC drive circuit to adjust the output voltage of the DC-DC drive circuit so that the output voltage is between 3.3V and 5V to meet the driving requirements of the first light-emitting element array 141, the second light-emitting element array 142, and the third light-emitting element array 143; the CPLD They are respectively connected to each TLC5940 chip of the driving unit 160, and the output end of each TLC5940 chip is respectively connected to a first light-emitting element, a second light-emitting element, and a third light-emitting element. The driving unit 160 is used to control the driving current of each light-emitting element according to the numerical information of the brightness information; and is used to control the DC-DC driving circuit to provide a first output voltage when the TLC5940 chip controls all the first light-emitting elements at the same time, to control the DC-DC driving circuit to provide a second output voltage when the TLC5940 chip controls all the second light-emitting elements at the same time, and to control the DC-DC driving circuit to provide a third output voltage when the TLC5940 chip controls all the third light-emitting elements at the same time.

[0027] Specifically, in the embodiment of the present application, the light source array module 140 is a 7x12 array light source module 140, comprising a total of 84 light-emitting elements. The light-emitting element driver chip of the driver unit 160 of the present application is a 16-channel light-emitting element driver chip. The driver unit 160 requires six 16-channel light-emitting element driver chips, each of which is connected to a CPLD. This allows precise and constant control of the driving current for each of the 84 light-emitting elements. The present embodiment requires only three switches 120 to control the on / off switching of the three light-emitting element arrays 141, 142, and 143. A single DC-DC driver circuit can output different driving voltages to control the activation of the R, G, and B light-emitting elements. The embodiment of the present application utilizes six 16-channel light-emitting element driver chips, three switches 120, and a CPLD. This allows precise adjustment of the brightness of each light-emitting element, meeting the light source requirements of regional dimming projection technology. The circuit structure is simple and cost-effective.

[0028] The projection method of the projection device according to the embodiment of the present application comprises the following steps:

[0029] Step 210: Obtain image information to be projected.

[0030] Step 220: Divide the image information to be projected into zones according to the light emitting element array.

[0031] For example, the light source array module 140 with an M×N light emitting element array divides the image information to be projected into M×N image information areas to be projected that are mapped one-to-one with the light emitting element array;

[0032] Step 230: Generate brightness information of each area of the image information to be projected of the three primary colors of the first primary color light, the second primary color light and the third primary color light.

[0033] The first primary color light is red, the second primary color light is green, and the third primary color light is blue. Specifically, based on the brightness of each area of the screen projection, single-primary color regional brightness information is generated for the image information area to be projected. That is, the brightness information of the first primary color light in each area of the first primary color picture frame, the brightness information of the third primary color light in each area of the third primary color picture frame, and the brightness information of the second primary color light in each area of the second primary color picture frame are generated.

[0034] Step 240: Receive a frame synchronization signal.

[0035] Specifically, the frame synchronization signal includes a first primary color frame synchronization signal, a second primary color frame synchronization signal, and a third primary color frame synchronization signal. In this embodiment, the first primary color frame synchronization signal, the second primary color frame synchronization signal, and the third primary color frame synchronization signal received are received in a certain timing sequence.

[0036] Step 250 : Send the brightness information of each region of the three primary colors image information to be projected to the driving control unit 150 in sequence.

[0037] Specifically, if the first primary color frame synchronization signal is received first, step 251 is executed: the first primary color brightness information of each region of the first primary color picture frame is sent to the driving control unit 150; if the second primary color frame synchronization signal is received, step 252 is executed: the second primary color brightness information of each region of the second primary color picture frame is sent to the driving control unit 150; and if the third primary color frame synchronization signal is received thereafter, step 253 is executed: the third primary color brightness information of each region of the third primary color picture frame is sent to the driving control unit 150.

[0038] Step 260 : the driving control unit 150 controls the three switches 120 to be turned on or off, the power supply circuit 110 outputs the driving voltage required to light up the light-emitting element, and sends the brightness information of each area of the three primary colors to be projected image information to the driving unit 160 in sequence.

[0039] Specifically, when the driving control unit 150 receives the brightness information containing the first primary color light, step 261 is executed: the driving control unit 150 sends a control signal to the first switch 121 to control the first switch 121 to be turned on, so that the power supply circuit 110 and the first light-emitting element array 141 are connected, and the power supply circuit 110 outputs the driving voltage of the first primary color light-emitting element chip to light up the first light-emitting element array 141; at the same time, the driving control unit 150 sends the brightness information of the first primary color light to the driving unit 160.

[0040] Step 270: The driving unit 160 controls the driving current of each light emitting element according to the numerical information of the brightness information.

[0041] Specifically, step 271 is executed: the driving unit 160 controls the driving current of each light-emitting element in the first light-emitting element array 141 according to the numerical information containing the brightness information of the first primary color light, lights up the first light-emitting element array 141, and controls the brightness of each light-emitting element in the first light-emitting element array 141.

[0042] Step 280: The first light emitting element array 141 outputs a first primary color picture frame, the third light emitting element array 143 outputs a third primary color picture frame, and the second light emitting element array 142 outputs a second primary color picture frame.

[0043] Specifically, the process includes step 281 : the first light emitting element array 141 outputs a first primary color picture frame.

[0044] Similarly, when the third primary color frame synchronization signal is received, steps 262 , 272 and 282 are executed, and the third light emitting element array 143 outputs the third primary color picture frame.

[0045] Specifically, in step 262, when the driving control unit 150 receives the third primary color brightness information of each area of the third primary color picture frame, the driving control unit 150 sends a control signal to the third switch 123 to control the third switch 123 to open, so that the power supply circuit 110 and the third light-emitting element array 143 are connected, and the power supply circuit 110 outputs the green light-emitting element chip driving voltage to light up the third light-emitting element array 143; at the same time, the driving control unit 150 sends the brightness information of each area containing the green image information to be projected to the driving unit 160.

[0046] Step 272 : the driving unit 160 controls the driving current of each light emitting element of the third light emitting element array 143 according to the numerical information of the third primary color brightness information table, and lights up the third light emitting element array 143 .

[0047] Step 282: The third light emitting element array 143 outputs a third primary color picture frame.

[0048] Similarly, when the second primary color frame synchronization signal is received, steps 263 , 273 and 283 are executed, and the second light emitting element array 142 outputs the second primary color picture frame.

[0049] Specifically, step 263: when the driving control unit 150 receives the second primary color brightness information, the driving control unit 150 sends a control signal to the second switch 122 to control the second switch 122 to open, so that the power supply circuit 110 and the second light-emitting element array 142 are connected, and the power supply circuit 110 outputs the blue light-emitting element chip driving voltage to light up the second light-emitting element array 142; at the same time, the driving control unit 150 sends the second primary color brightness information containing the second primary color picture frame in each area to the driving unit 160.

[0050] Step 273 : the driving unit 160 controls the driving current of each light emitting element of the second light emitting element array 142 according to the numerical information of the second primary color brightness information table, and lights up the second light emitting element array 142 .

[0051] Step 283: The second light emitting element array 142 outputs a second primary color picture frame.

[0052] Step 290: Output a color frame.

[0053] Specifically, by utilizing the visual persistence effect of human eyes, three single-primary-color picture frames, namely the first primary-color picture frame, the second primary-color picture frame and the third primary-color picture frame, are combined into a pair of color picture frames.

[0054] Furthermore, step 250 : the power supply circuit 110 outputs the driving voltage required to light up the light-emitting element, which includes: the driving control unit 150 adjusts the output voltage of the power supply circuit 110 .

[0055] When the drive control unit 150 receives the first primary color brightness information for each region of the first primary color frame, the drive control unit 150 sends a control number to the digitally controlled potentiometer 112 of the DC-DC drive circuit to control the DC-DC drive circuit to output a voltage to illuminate the first light-emitting element array 141. When the drive control unit 150 receives the second primary color brightness information, the drive control unit 150 sends a control number to the digitally controlled potentiometer 112 of the DC-DC drive circuit to control the DC-DC drive circuit to output a voltage to illuminate the second light-emitting element array 142. When the drive control unit 150 receives the third primary color brightness information, the drive control unit 150 sends a control number to the digitally controlled potentiometer 112 of the DC-DC drive circuit to control the DC-DC drive circuit to output a voltage to illuminate the third light-emitting element array 143.

[0056] The above is only an implementation method of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of this application, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A projection device, characterized in that: include: a light source array module, comprising a first light-emitting element array emitting a first primary color light, a second light-emitting element array emitting a second primary color light, and a third light-emitting element array emitting a third primary color light, wherein the first light-emitting element array, the second light-emitting element array, and the third light-emitting element array are each divided into M×N lighting areas; an image processing unit, configured to divide the image to be projected into M×N image regions and obtain brightness information of the first primary color light, the second primary color light, and the third primary color light of each image region, wherein the image regions correspond one-to-one to the illumination regions of the light source array module; a driving unit connected to the first light-emitting element array, the second light-emitting element array, the third light-emitting element array, and the image processing unit, configured to sequentially drive the first light-emitting element array, the second light-emitting element array, and the third light-emitting element array in accordance with brightness information of the first primary color light, the second primary color light, and the third primary color light of each image area, and control the brightness of each illumination area of the first light-emitting element array, the second light-emitting element array, and the third light-emitting element array; Each output end of the driving unit is connected to a first light-emitting element, a second light-emitting element and a third light-emitting element at the same time.

2. The projection device according to claim 1, wherein: The driving unit is a current driving unit, configured to drive the first light emitting element array, the second light emitting element array, and the third light emitting element array by a current corresponding to the brightness information.

3. The projection device according to claim 1, wherein: It also includes a driving control unit connected between the image processing unit and the driving unit, for sending the brightness information to the driving unit and controlling the driving unit to drive the first light-emitting element array, the second light-emitting element array and the third light-emitting element array.

4. The projection device according to claim 3, wherein: The projection device further comprises: Power supply circuit; a first switch connected between the power supply circuit and the first light emitting element array; a second switch connected between the power supply circuit and the second light emitting element array; a second switch connected between the power supply circuit and the third light emitting element array; The driving control unit is connected to the first switch, the second switch and the third switch, and is used to connect the first switch when controlling the driving unit to drive the first light-emitting element array, connect the second switch when controlling the driving unit to drive the second light-emitting element array, and connect the third switch when controlling the driving unit to drive the third light-emitting element array.

5. The projection device according to claim 4, wherein: The first switch, the second switch, and the third switch each include an NMOS transistor and a PMOS transistor, wherein the control ends of the NMOS transistor and the PMOS transistor are connected to the drive control unit, the first end of the NMOS transistor is connected to the power supply circuit, and the second end of the NMOS transistor is connected to the light-emitting element array; the first end of the PMOS transistor is connected to the light-emitting element array, and the second end of the PMOS transistor is grounded.

6. The projection device according to claim 4, wherein: The driving control unit is connected to the power supply circuit and is used to control the power supply circuit to provide a first output voltage when controlling the driving unit to drive the first light-emitting element array, to control the power supply circuit to provide a second output voltage when controlling the driving unit to drive the second light-emitting element array, and to control the power supply circuit to provide a third output voltage when controlling the driving unit to drive the third light-emitting element array.

7. The projection device according to claim 6, wherein: The power supply circuit includes a DC-DC chip and a digitally controlled potentiometer. The resistance of the digitally controlled potentiometer is adjustable. The output voltage of the DC-DC chip is controlled by the resistance of the digitally controlled potentiometer. The digitally controlled potentiometer is connected to the drive control unit. The DC-DC chip is connected to the first switch, the second switch, and the third switch. When the drive unit drives the first light-emitting element array, the second light-emitting element array, and the third light-emitting element array, the drive control unit sends control signals to the digitally controlled potentiometer to control the resistance adjustment of the digitally controlled potentiometer, so that the DC-DC chip outputs the first output voltage, the second output voltage, and the third output voltage.

8. The projection device according to claim 7, wherein: The digitally controlled potentiometer is connected between the voltage adjustment pin and the switch control pin of the DC-DC chip, and the serial data input pin of the digitally controlled potentiometer is connected to the drive control unit. The drive control unit sends a control number to the digitally controlled potentiometer so that the DC-DC chip outputs the corresponding drive voltage.

9. The projection device according to claim 3, wherein: The image processing unit is used to receive a frame synchronization signal and, under the control of the frame synchronization signal, send brightness information of the first primary color light, the second primary color light, and the third primary color light to the driving control unit in sequence.

10. The projection device according to claim 3, wherein: The current magnitude of the output end of the driving unit is controlled by the driving control unit.

Images