Laser projection equipment

Abstract

The present application discloses a laser projection device, including a blue laser, the blue laser emitted sequentially irradiates three different areas of a fluorescent wheel to generate yellow fluorescence, green fluorescence and blue laser; the above three-color light sequentially passes through a color filter wheel to generate four-color light, including red fluorescence, yellow fluorescence, green fluorescence and blue laser; a driving circuit receives an image signal of a projected image, the image signal includes three color initial values ​​of each pixel in the projected image; the driving circuit determines the four color target values ​​of the pixel according to the three color initial values ​​of each pixel, and the light valve is used to sequentially receive the irradiation of the four colors of light, and is controlled to flip by the driving circuit according to the corresponding color target value. Since the present application can increase the color light generated by the light source, and merge the increased color light generated by the light source into the displayed projected image, the brightness of the displayed image is improved.

Description

[0001] This application is a divisional application based on Chinese invention application 202010156634.1 (2020-03-09), invention name: Laser projection method and device. Technical Field

[0002] The present disclosure relates to the field of laser projection, and in particular to a laser projection method and device. Background Art

[0003] At present, laser projection equipment may include a driving circuit, a blue laser, a fluorescent wheel (or also called a color filter wheel), a light valve and a projection lens. In the process of projecting and displaying the image to be projected, the blue laser emitted by the blue laser is sequentially irradiated onto different areas of the fluorescent wheel, thereby generating three-color light, which may include blue light, red light and green light. The driving circuit may receive an image signal of the image to be projected sent by a front-end device (such as a computer), and the image signal includes the red value, green value and blue value of each pixel in the image to be projected. Afterwards, the driving circuit may control the flipping of the light valve according to the color of the light irradiated by the light source to the light valve, and the red value, green value and blue value of the pixel. The light valve may modulate the light of each color into an image beam, and transmit the image beam to the projection lens, thereby realizing the display of the image.

[0004] However, since only three-color light is projected to realize image display, the brightness of the displayed image is low. Summary of the invention

[0005] The embodiments of the present disclosure provide a laser projection method and device, which can solve the problem in the related art that the brightness of the displayed image is low because only three-color light is projected to realize the display of the image. The technical solution is as follows:

[0006] On the one hand, a laser projection method is provided, which is applied to a driving circuit of a laser projection device, wherein the laser projection device further comprises: a light source and a light valve, and the method comprises:

[0007] receiving an image signal of a projected image, the image signal comprising a first color initial value, a second color initial value, and a third color initial value for each pixel in the projected image;

[0008] Determine a first color target value, a second color target value, a third color target value, and a fourth color target value of the pixel according to the first color initial value, the second color initial value, and the third color initial value of each pixel, wherein the sum of the first color target value, the second color target value, the third color target value, and the fourth color target value is greater than or equal to the sum of the first color initial value, the second color initial value, and the third color initial value;

[0009] The light valve is controlled to flip according to the color of the light emitted from the light source to the light valve, and the first color target value, the second color target value, the third color target value and the fourth color target value of the pixel.

[0010] Optionally, determining the first color target value, the second color target value, the third color target value, and the fourth color target value of the pixel according to the first color initial value, the second color initial value, and the third color initial value of each pixel includes:

[0011] If the first color initial value, the second color initial value, and the third color initial value do not meet the target condition, determining that the third color target value is equal to the third color initial value;

[0012] Determining the first color target value, the second color target value, and the fourth color target value according to the first color initial value and the second color initial value;

[0013] The target conditions include one or more of the following conditions:

[0014] The target color initial value among the first color initial value, the second color initial value and the third color initial value is a color upper limit value, and other color initial values ​​except the target color initial value are color lower limit values;

[0015] The first color initial value, the second color initial value, and the third color initial value are all the color upper limit values.

[0016] Optionally, determining the first color target value, the second color target value, and the fourth color target value according to the first color initial value and the second color initial value of the pixel includes:

[0017] respectively detecting whether the first color initial value is greater than a first threshold value, and whether the second color initial value is greater than a second threshold value;

[0018] If the first color initial value is greater than the first threshold, and the second color initial value is less than or equal to the second threshold; or, the first color initial value is less than or equal to the first threshold, and the second color initial value is greater than the second threshold; or, the first color initial value is less than or equal to the first threshold, and the second color initial value is less than or equal to the second threshold, compare the first ratio with the second ratio;

[0019] If the first ratio is equal to the second ratio, determining that the first color target value and the second color target value are both equal to the color lower limit value, and determining that the fourth color target value is equal to the product of the third ratio and the color upper limit value;

[0020] Among them, the first ratio is the ratio of the first color initial value to the second color initial value, the second ratio is the ratio of the first threshold to the second threshold, the third ratio is the ratio of the first color initial value to the first threshold, or the third ratio is the ratio of the second color initial value to the second threshold.

[0021] Optionally, after comparing the first ratio with the second ratio, if the first ratio is smaller than the second ratio, the method further includes:

[0022] Determine that the first color target value is equal to the color lower limit value;

[0023] Determine that the fourth color target value is equal to the product of a fourth ratio and the color upper limit value, wherein the fourth ratio is the ratio of the first color initial value to the first threshold value;

[0024] Determine that the second color target value is equal to the product of the fifth ratio and the color upper limit value, the fifth ratio is the ratio of the first difference to the second difference, the first difference is the difference between the second color initial value and the product of the fourth ratio and the second threshold value, and the second difference is the difference between the color upper limit value and the second threshold value.

[0025] Optionally, after comparing the first ratio with the second ratio, if the first ratio is greater than the second ratio, the method further includes:

[0026] Determine that the second color target value is equal to the color lower limit value;

[0027] Determine that the fourth color target value is equal to the product of a sixth ratio and the color upper limit value, wherein the sixth ratio is the ratio of the second color initial value to the second threshold value;

[0028] Determine that the first color target value is equal to the product of the seventh ratio and the color upper limit value, the seventh ratio is the ratio of the third difference to the fourth difference, the third difference is the difference between the first color initial value and the product of the sixth ratio and the first threshold value, and the fourth difference is the difference between the color upper limit value and the first threshold value.

[0029] Optionally, after respectively detecting whether the first color initial value is greater than a first threshold value and whether the second color initial value is greater than a second threshold value, the method further includes:

[0030] If the first color initial value is greater than the first threshold value, and the second color initial value is greater than the second threshold value, determining the fourth color target value to be the color upper limit value;

[0031] Determine that the first color target value is equal to the product of an eighth ratio and the color upper limit value, the eighth ratio being the ratio of a difference between the first color initial value and the first threshold value to a fourth difference value, the fourth difference being the difference between the color upper limit value and the first threshold value;

[0032] Determine that the second color target value is equal to the product of the ninth ratio and the color upper limit value, the ninth ratio is the ratio of the difference between the second color initial value and the second threshold value to the second difference, and the second difference is the difference between the color upper limit value and the second threshold value.

[0033] Optionally, if the first color initial value, the second color initial value, and the third color initial value meet the target condition, the method further includes:

[0034] If the target color initial value among the first color initial value, the second color initial value and the third color initial value is a color upper limit value, and other color initial values ​​except the target color initial value are color lower limit values, determine that the color target value corresponding to the target color initial value is equal to the color upper limit value, and determine that other color target values ​​except the color target value corresponding to the target color initial value are equal to the color lower limit value;

[0035] If the first color initial value, the second color initial value and the third color initial value are all the color upper limit values, it is determined that the first color target value, the second color target value, the third color target value and the fourth color target value are all equal to the color upper limit value.

[0036] On the other hand, a laser projection device is provided, the laser projection device comprising: a driving circuit, a light source and a light valve;

[0037] The driving circuit is used to receive an image signal of a projected image, wherein the image signal includes a first color initial value, a second color initial value, and a third color initial value of each pixel in the projected image;

[0038] The driving circuit is further used to determine a first color target value, a second color target value, a third color target value and a fourth color target value of the pixel according to the first color initial value, the second color initial value and the third color initial value of each pixel, wherein the sum of the first color target value, the second color target value, the third color target value and the fourth color target value is greater than or equal to the sum of the first color initial value, the second color initial value and the third color initial value;

[0039] The driving circuit is further used to control the flipping of the light valve according to the color of the light irradiated by the light source to the light valve, and the first color target value, the second color target value, the third color target value and the fourth color target value of the pixel.

[0040] Optionally, the driving circuit is further used for:

[0041] If the first color initial value, the second color initial value, and the third color initial value do not meet the target condition, determining that the third color target value is equal to the third color initial value;

[0042] Determining the first color target value, the second color target value, and the fourth color target value according to the first color initial value and the second color initial value;

[0043] The target conditions include one or more of the following conditions:

[0044] The target color initial value among the first color initial value, the second color initial value and the third color initial value is a color upper limit value, and other color initial values ​​except the target color initial value are color lower limit values;

[0045] The first color initial value, the second color initial value, and the third color initial value are all the color upper limit values.

[0046] Optionally, the driving circuit is further used for:

[0047] respectively detecting whether the first color initial value is greater than a first threshold value, and whether the second color initial value is greater than a second threshold value;

[0048] If the first color initial value is greater than the first threshold, and the second color initial value is less than or equal to the second threshold; or, the first color initial value is less than or equal to the first threshold, and the second color initial value is greater than the second threshold; or, the first color initial value is less than or equal to the first threshold, and the second color initial value is less than or equal to the second threshold, compare the first ratio with the second ratio;

[0049] If the first ratio is equal to the second ratio, determine that the first color target value is equal to the color lower limit value, determine that the second color target value is equal to the color lower limit value, and determine that the fourth color target value is equal to the product of the third ratio and the color upper limit value;

[0050] Among them, the first ratio is the ratio of the first color initial value to the second color initial value, the second ratio is the ratio of the first threshold to the second threshold, the third ratio is the ratio of the first color initial value to the first threshold, or the third ratio is the ratio of the second color initial value to the second threshold.

[0051] The beneficial effects brought by the technical solution provided by the embodiments of the present disclosure include at least:

[0052] The disclosed embodiment provides a laser projection method and device, which can determine the first color target value, the second color target value, the third color target value and the fourth color target value of each pixel in the projected image according to the first color initial value, the second color initial value and the third color initial value of each pixel. And control the flipping of the light valve according to the color of the light irradiated by the light source to the light valve, and the first color target value, the second color target value, the third color target value and the fourth color target value of the pixel. The disclosed embodiment increases the color light generated by the light source, determines the color target value corresponding to the four-color light according to the color initial value of the three colors of each pixel in the projected image, and controls the flipping of the light valve according to the color target value corresponding to the four-color light, so as to merge the increased color light into the displayed projected image, which improves the brightness of the displayed image compared to the related art that only projects three-color light to realize the display of the image. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0054] Figure 1 is a structural schematic diagram of a laser projection device provided by an embodiment of the present disclosure;

[0055] Figure 2 is a schematic structural diagram of another laser projection device provided by an embodiment of the present disclosure;

[0056] Figure 3 is a flow chart of a laser projection method provided by an embodiment of the present disclosure;

[0057] Figure 4 is a flow chart of another laser projection method provided by an embodiment of the present disclosure;

[0058] Figure 5The present invention provides a flowchart for determining a first color target value, a second color target value, and a fourth color target value according to a first color initial value and a second color initial value. DETAILED DESCRIPTION

[0059] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0060] Figure 1 and Figure 2 Schematic diagram of the structure of a laser projection device provided by an embodiment of the present disclosure. Figure 1 and Figure 2 As shown, the laser projection device may include a driving circuit 10 , a light source 20 and a light valve 30 .

[0061] The driving circuit 10 may be a digital light processing (DLP) driving chip. The light source 20 may be a laser light source, for example, the laser light source may include a blue laser. Alternatively, the light source 20 may be a light source other than a laser light source. For example, the light source 20 may be a light bulb or a light emitting diode (LED). The light valve 30 may be a digital micro-mirror device (DMD).

[0062] refer to Figure 2 The laser projection device may further include a fluorescent wheel 80 and a color filter wheel 90. The blue laser generated by the light source 20 is sequentially irradiated onto three different regions of the fluorescent wheel 80, thereby generating three-color light (the three-color light may include yellow fluorescence, green fluorescence and blue laser), and the three-color light sequentially passes through the color filter wheel 90 to generate four-color light, which is sequentially irradiated onto the light valve 30.

[0063] Figure 3 is a flow chart of a laser projection method provided by an embodiment of the present disclosure. The laser projection method can be applied to Figure 1 and Figure 2 In the driving circuit 10 of the laser projection device shown in FIG. 1 , the laser projection device may further include a light source 20 and a light valve 30. Figure 3 As shown, the method may include:

[0064] Step 301: Receive an image signal of a projection image.

[0065] The image signal may include a first color initial value, a second color initial value, and a third color initial value of each pixel in the projected image. The first color initial value, the second color initial value, and the third color initial value of each pixel may be represented by an 8-bit digital signal.

[0066] Optionally, the first color may be red, the second color may be green, and the third color may be blue. Accordingly, the first color initial value may be represented by R, the second color initial value may be represented by G, and the third color initial value may be represented by B. For example, the first color initial value R may be 100, the second color initial value G may be 120, and the third color initial value B may be 200.

[0067] refer to Figure 1 The driving circuit 10 can be connected to the front-end device 00. When the laser projection device projects and displays the projection image, the front-end device 00 can send the image signal of the projection image to the driving circuit 10. Correspondingly, the driving circuit 10 can receive the image signal of the projection image sent by the front-end device 00. Optionally, the front-end device 00 can be a computer.

[0068] Step 302: Determine a first color target value, a second color target value, a third color target value, and a fourth color target value of each pixel according to the first color initial value, the second color initial value, and the third color initial value of each pixel.

[0069] The sum of the first color target value, the second color target value, the third color target value and the fourth color target value is greater than or equal to the sum of the first color initial value, the second color initial value and the third color initial value.

[0070] Optionally, the fourth color may be yellow. The first color target value may be represented by R1, the second color target value may be represented by G1, the third color target value may be represented by B1, and the fourth color target value may be represented by Y1.

[0071] Step 303 : Control the light valve to flip according to the color of the light irradiated from the light source to the light valve, and the first color target value, the second color target value, the third color target value and the fourth color target value of the pixel.

[0072] In the embodiment of the present disclosure, when the color of the light irradiated from the light source to the light valve is the first color, the driving circuit 10 can control the light valve to flip according to the first color target value of each pixel. The first color can be red, that is, the light irradiated from the light source 20 to the light valve 30 is red fluorescence or red laser. After determining the first color target value R1, the driving circuit 10 controls the light valve 30 to flip according to the first color target value R1 of each pixel when the color of the light irradiated from the light source 20 to the light valve 30 is red.

[0073] The flipping time of the light valve 30 is positively correlated with the first color target value R1, and the illumination intensity of the red fluorescent light or the red laser finally projected onto the projection screen is positively correlated with the first color target value R1.

[0074] When the color of the light irradiated from the light source to the light valve is the second color, the driving circuit 10 may control the light valve to flip according to the second color target value of each pixel. Optionally, the second color may be green, that is, the light irradiated from the light source 20 to the light valve 30 is green fluorescence or green laser. After determining the second color target value G1, the driving circuit 10 controls the light valve 30 to flip according to the second color target value G1 of each pixel when the color of the light irradiated from the light source 20 to the light valve 30 is green.

[0075] The flipping time of the light valve 30 is positively correlated with the magnitude of the second color target value G1, and the illumination intensity of the green fluorescent light or the green laser light finally projected onto the projection screen is positively correlated with the magnitude of the second color target value G1.

[0076] When the color of the light irradiated from the light source to the light valve is the third color, the driving circuit 10 may control the light valve to flip according to the third color target value of each pixel. Optionally, the third color may be blue, that is, the light irradiated from the light source 20 to the light valve 30 is a blue laser. After determining the third color target value, the driving circuit 10 controls the light valve 30 to flip according to the third color target value B1 of each pixel when the color of the light irradiated from the light source 20 to the light valve 30 is blue.

[0077] The flipping time of the light valve 30 is positively correlated with the size of the third color target value B1, and the illumination intensity of the blue laser finally projected onto the projection screen is positively correlated with the size of the third color target value B1.

[0078] When the color of the light irradiated from the light source to the light valve is the fourth color, the driving circuit 10 may control the light valve to flip according to the fourth color target value of each pixel. Optionally, the fourth color may be yellow, that is, the light irradiated from the light source 20 to the light valve 30 is yellow light. After determining the fourth color target value, the driving circuit 10 controls the light valve 30 to flip according to the fourth color target value B1 of each pixel when the color of the light irradiated from the light source 20 to the light valve 30 is yellow.

[0079] The flipping time of the light valve 30 is positively correlated with the size of the fourth color target value Y1, and the illumination intensity of the yellow light finally projected onto the projection screen is positively correlated with the size of the fourth color target value Y1.

[0080] In summary, the embodiment of the present disclosure provides a laser projection method, which can determine the first color target value, the second color target value, the third color target value and the fourth color target value of each pixel in the projected image according to the first color initial value, the second color initial value and the third color initial value of each pixel. And control the flipping of the light valve according to the color of the light irradiated by the light source to the light valve, and the first color target value, the second color target value, the third color target value and the fourth color target value of the pixel. The embodiment of the present disclosure increases the color light generated by the light source, determines the color target value corresponding to the four-color light according to the color initial values ​​of the three colors of each pixel in the projected image, and controls the flipping of the light valve according to the color target values ​​corresponding to the four-color light, thereby integrating the increased color light into the displayed projected image, which improves the brightness of the displayed image compared to the related art of only projecting three-color light to realize the display of the image.

[0081] Figure 4 is a flow chart of another laser projection method provided by an embodiment of the present disclosure. The laser projection method can be applied to Figure 1 and Figure 2 In the driving circuit 10 of the laser projection device shown in FIG. 1 , the laser projection device may further include a light source 20 and a light valve 30. Figure 4 As shown, the method may include:

[0082] Step 401: Receive an image signal of a projection image.

[0083] The image signal may include a first color initial value, a second color initial value, and a third color initial value of each pixel in the projected image. Optionally, the first color initial value, the second color initial value, and the third color initial value of each pixel may be represented by an 8-bit digital signal.

[0084] The embodiment of the present disclosure is described by taking the first color as red, the second color as green, and the third color as blue as an example. The first color initial value can be represented by R, the second color initial value can be represented by G, and the third color initial value can be represented by B. For example, the first color initial value R can be 100, the second color initial value G can be 120, and the third color initial value B can be 200.

[0085] refer to Figure 1 The driving circuit 10 can be connected to the front-end device 00. When the laser projection device projects and displays the projection image, the front-end device 00 can send the image signal of the projection image to the driving circuit 10. Correspondingly, the driving circuit 10 can receive the image signal of the projection image sent by the front-end device 00. For example, the front-end device can be a computer.

[0086] Step 402: Detect whether the first color initial value, the second color initial value, and the third color initial value meet the target condition.

[0087] In the embodiment of the present disclosure, after receiving the image signal of the projected image, the driving circuit 10 can detect whether the first color initial value R, the second color initial value G, and the third color initial value B of each pixel in the image signal meet the target condition. If the first color initial value R, the second color initial value G, and the third color initial value B do not meet the target condition, it indicates that the color presented by the pixel in the projected image is not a pure color, and color mixing is required, and step 403 is executed. If the first color initial value, the second color initial value, and the third color initial value meet the target condition, it indicates that the color presented by the pixel in the projected image is a pure color, and steps 405 and 406 can be executed.

[0088] The target condition may include one or more of the following conditions:

[0089] (1) The target color initial value among the first color initial value, the second color initial value and the third color initial value is the color upper limit value, and the other color initial values ​​except the target color initial value are the color lower limit values. Optionally, the color upper limit value K1 can be 255, and the color lower limit value K2 can be 0.

[0090] For example, if the target color value is the first color initial value R, that is, the first color initial value is 255, the second color initial value G is 0, and the third color initial value B is 0, it indicates that the color presented by the pixel in the projected image is 100% pure red.

[0091] If the target color value is the second color initial value G, that is, the second color initial value G can be 255, the first color initial value R is 0, and the third color initial value B is 0, it indicates that the color presented by the pixel in the projected image is 100% pure green.

[0092] If the target color value is the third color initial value B, that is, the third color initial value B is 255, the first color initial value R is 0, and the second color initial value G can be 0, it indicates that the color presented by the pixel in the projected image is 100% pure blue.

[0093] (2) The first color initial value, the second color initial value and the third color initial value are all color upper limit values.

[0094] For example, if the first color initial value R of a pixel is 255, the second color initial value G is 255, and the third color initial value B is 255, it indicates that the color presented by the pixel in the projected image is 100% pure white.

[0095] Step 403: Determine whether the third color target value is equal to the third color initial value.

[0096] In the embodiment of the present disclosure, after determining that the first color initial value R, the second color initial value G, and the third color initial value B do not meet the target condition, the driving circuit 10 may determine that the third color target value B1 is equal to the third color initial value B, where B1=B. For example, if the third color initial value B is 200, then the third color target value B1=200 may be determined.

[0097] Step 404: Determine a first color target value, a second color target value, and a fourth color target value according to the first color initial value and the second color initial value.

[0098] In the embodiment of the present disclosure, after determining that the first color initial value R, the second color initial value G, and the third color initial value B do not meet the target condition, the driving circuit 10 can determine the first color target value R1, the second color target value G1, and the fourth color target value Y1 according to the first color initial value and the second color initial value. Among them, the fourth color can be yellow, and the fourth color value can be represented by Y1. Since red and green light are mixed to form yellow light, the color target value of red fluorescence and the color target value of green light can be expressed by the color target value of yellow light. The red light can be red fluorescence, or red laser. The green light can be green fluorescence or green laser. The yellow light can be yellow fluorescence.

[0099] Optional, such as Figure 5 As shown, step 404 may include:

[0100] Step 4041: Detect whether the initial value of the first color is greater than the first threshold value, and detect whether the initial value of the second color is greater than the second threshold value.

[0101] In the embodiment of the present disclosure, after determining that the first color initial value R, the second color initial value G, and the third color initial value B do not meet the target condition, the driving circuit 10 can respectively detect whether the first color initial value R is greater than the first threshold value X1, and whether the second color initial value G is greater than the second threshold value X2. If the first color initial value R is greater than the first threshold value X1, and the second color initial value G is less than or equal to the second threshold value X2. Or, the first color initial value R is less than or equal to the first threshold value X1, and the second color initial value G is greater than the second threshold value X2. Or, the first color initial value R is less than or equal to the first threshold value X1, and the second color initial value G is less than or equal to the second threshold value X2, then step 4042 is executed. If the first color initial value R is greater than the first threshold value X1, and the second color initial value G is greater than the second threshold value X2, indicating that the color target value of the yellow light cannot fully express the first color initial value R and the second color initial value G, then step 4047 can be executed.

[0102] The first threshold value X1 and the second threshold value X2 may be fixed values ​​pre-stored in the driving circuit 10. The first threshold value X1 represents the limit value of the initial color value of the red light that can be expressed by the color target value of the yellow light. The second threshold value X2 represents the limit value of the initial color value of the green light that can be expressed by the color target value of the yellow light.

[0103] For example, the first threshold value X1 may be 141.7, and the second threshold value X2 may be 115.9.

[0104] Step 4042: Compare the first ratio with the second ratio.

[0105] When the driving circuit determines that the first color initial value R is not greater than the first threshold value, and the second color initial value G is not greater than the second threshold value, the first ratio N1 and the second ratio N2 can be compared. If the first ratio N1 is equal to the second ratio N2, it indicates that the color target value of the yellow light can fully express the first color initial value R and the second color initial value G, and step 4043 can be performed. If the first ratio N1 is less than the second ratio N2, it indicates that the color target value of the yellow light can fully express the first color initial value R, but cannot fully express the second color initial value G. Then step 4044 can be performed. If the first ratio N1 is greater than the second ratio N2, it indicates that the color target value of the yellow light can fully express the second color initial value G, but cannot fully express the first color initial value R, and step 4045 can be performed.

[0106] The first ratio N1 may be the ratio of the first color initial value R to the second color initial value G, that is, N1= The second ratio N2 is the ratio of the first threshold value X1 to the second threshold value X2, that is, N2= .

[0107] For example, if the first threshold value X1 is 141.7 and the second threshold value X2 is 115.9, then N2= =1.2226.

[0108] Step 4043: determine that the first color target value is equal to the color lower limit value, determine that the second color target value is equal to the color lower limit value, and determine that the fourth color target value is equal to the product of the third ratio and the color upper limit value.

[0109] In the embodiment of the present disclosure, when the driving circuit 10 determines that the first ratio N1 is equal to the second ratio N2, it can be determined that the color target value of the yellow light can fully express the first color initial value R and the second color initial value G, and therefore it can be determined that the first color target value R1 is equal to the color lower limit value K2, where R1=K2, the second color target value G1 is equal to the color lower limit value K2, where G1=K2, and the fourth color target value Y1 is equal to the third ratio N3×color upper limit value K1, where Y1=N3×K1.

[0110] The third ratio N3 is the ratio of the first color initial value R to the first threshold value X1. Or the third ratio N3 is the ratio of the second color initial value G to the second threshold value X2. = .

[0111] For example, assuming that the first color initial value R is 14.17, the second color initial value G is 11.59, the first threshold value X1 is 141.7, the second threshold value X2 is 115.9, the color upper limit value K1 is 255, and the color lower limit value K2 is 0, then the first ratio N1= = =1.2226, the second ratio N2= =1.2226, the third ratio N3= = =0.1. Since N1=N2, the driving circuit 10 can determine the first color target value R1=0, the second color target value G1=0, and the fourth color target value Y1=N3×255=0.1×255=25.5.

[0112] Step 4044, determine that the first color target value is equal to the color lower limit value, determine that the fourth color target value is equal to the product of the fourth ratio and the color upper limit value, and determine that the second color target value is equal to the product of the fifth ratio and the color upper limit value.

[0113] In the embodiment of the present disclosure, after determining that the first ratio N1 is less than the second ratio N2, the driving circuit 10 can determine that the color target value of the yellow light can fully express the first color initial value R, but cannot fully express the second color initial value G. Therefore, the driving circuit 10 can determine that the first color target value R1 is equal to the color lower limit value K2, R1=K2, determine that the fourth color target value Y1 is equal to the product of the fourth ratio N4 and the color upper limit value K1, Y1=N4×K1, and determine that the second color target value G1 is equal to the product of the fifth ratio N5 and the color upper limit value K1, G1=N5×K1.

[0114] The fourth ratio N4 is the ratio of the first color initial value R to the first threshold value X1, and N4= The fifth ratio N5 is the ratio of the first difference d1 to the second difference d2, the first difference d1 is the difference between the product of the second color initial value G and the fourth ratio N4 and the second threshold value X2, the second difference d2 is the difference between the color upper limit value K1 and the second threshold value X2, the N5= = The second difference d2 is the limit value of the initial color value of the red light that can be expressed by the color target value of the red light.

[0115] For example, assuming that the first color initial value R is 100, the second color initial value G is 120, the first threshold value X1 is 141.7, the second threshold value X2 is 115.9, the color upper limit value is 255, and the color lower limit value is 0, the driving circuit 10 can determine the first ratio N1= = =0.83, the second ratio N2= =1.2226, the fourth ratio N4= = =0.7057, the fifth ratio N5= = = =0.2747. Since the first ratio N1=0.83 is less than the second ratio N2=1.2226, the driving circuit 10 can determine the first color target value R1=0, the fourth color target value Y1=N4×255=0.7057×255=180, and the second color target value G1=N5×K1=0.2747×255=70.

[0116] Step 4045, determine that the second color target value is equal to the color lower limit value, determine that the fourth color target value is equal to the product of the sixth ratio and the color upper limit value, and determine that the first color target value is equal to the product of the seventh ratio and the color upper limit value.

[0117] In the embodiment of the present disclosure, after determining that the first ratio N1 is greater than the second ratio N2, the driving circuit 10 can determine that the color target value of the yellow light can fully express the second color initial value G, but cannot fully express the first color initial value R, then the second color target value G1 can be determined to be the color lower limit value K2, where G1=K2, and the fourth color target value Y1 is determined to be equal to the product of the sixth ratio N6 and the color upper limit value K1, where Y1=N6×K1, and the first color target value R1 is determined to be equal to the product of the seventh ratio N7 and the color upper limit value K1, where R1=N7×K1.

[0118] The sixth ratio N6 is the ratio of the second color initial value G to the second threshold value X2, and N6= The seventh ratio N7 is the ratio of the third difference d3 to the fourth difference d4, the third difference d3 is the difference between the first color initial value R and the product of the sixth ratio N6 and the first threshold value X1, the fourth difference d4 is the difference between the color upper limit value K1 and the first threshold value X1, the N7= = The fourth difference is a limit value of the initial color value of the green light that can be expressed by the color target value of the green light.

[0119] For example, assuming that the first color initial value R is 130, the second color initial value G is 100, the first threshold value X1 is 141.7, the second threshold value X2 is 115.9, the color upper limit value is 255, and the color lower limit value is 0, the driving circuit 10 can determine the first ratio N1= = =1.3, the second ratio N2= =1.2226, the sixth ratio N6= = =0.8628. The seventh ratio N7= = = =0.0683. Since the first ratio N1=1.3 is greater than the second ratio N2=1.2226, the driving circuit 10 can determine the second color target value G1=0, the fourth color target value Y1=N6×K1=0.8628×255=220, and the first color target value R1=N7×K1=0.0683×255=17.

[0120] Step 4046, determine that the fourth color target value is the color upper limit value, determine that the first color target value is equal to the product of the eighth ratio and the color upper limit value, and determine that the second color target value is equal to the product of the ninth ratio and the color upper limit value.

[0121] When the driving circuit 10 determines that the first color initial value R is greater than the first threshold value X1, and the second color initial value G is greater than the second threshold value X2, it can be determined that the color target value of the yellow light cannot fully express the second color initial value G and the first color initial value R, and the driving circuit 10 can determine that the fourth color target value Y1 is equal to the color upper limit value K1, and Y1=K1. The first color target value R1 is determined to be equal to the product of the eighth ratio N8 and the color upper limit value K1, and R1=N8×K1. And the second color target value G1 is determined to be equal to the product of the ninth ratio N9 and the color upper limit value K1, and G1=N9×K1.

[0122] The eighth ratio N8 is the ratio of the difference between the first color initial value R and the first threshold value X1 to the fourth difference d4. N8= The ninth ratio N9 is the ratio of the difference between the second color initial value G and the second threshold value X2 to the second difference d2, and N9= .

[0123] For example, assuming that the first color initial value R is 150, the second color initial value G is 120, the first threshold value X1 is 141.7, the second threshold value X2 is 115.9, the color upper limit value K1 is 255, and the color lower limit value K2 is 0, then the eighth ratio N8= = = =0.0733, the ninth ratio N9= = = =0.0072. Since the first color initial value R=150 is greater than the second color initial value G=120, the driving circuit 10 can determine the fourth color value Y1=255, determine the first color target value R1=N8×255=0.0733×255=19, and determine the second color target value G1=N9×255=0.0072×255=2.

[0124] In the embodiment of the present disclosure, after color mixing, the sum of the first color target value R1, the second color target value G1, the third color target value B1 and the fourth color target value Y1 is greater than the sum of the first color initial value R, the second color initial value G and the third color initial value B, that is, R1+G1+B1+Y1>R+G+B.

[0125] For example, if the first color initial value R is 150, the second color initial value G is 120, and the third color initial value B1 is 200, the driving circuit 10 can determine the first color target value R1=19, the second color target value G1=2, the third target value B1=200 and the fourth color target value Y1=255 by executing the above steps 403 and 404. R1+G1+B1+Y1=19+2+200+255=476, and R+G+B=150+120+200=470. Since 476>470, it can be seen that R1+G1+B1+Y1>R+G+B.

[0126] Step 405 , determine that the color target value corresponding to the target color initial value is equal to the color upper limit value, and determine that the color target values ​​other than the color target value corresponding to the target color initial value are equal to the color lower limit value.

[0127] In the embodiment of the present disclosure, if the target color initial value among the first color initial value R, the second color initial value G and the third color initial value B is determined to be the color upper limit value, and the other color initial values ​​except the target color initial value are the color lower limit values, then the driving circuit 10 can determine that the color target value corresponding to the target color initial value is equal to the color upper limit value K1, and determine that the color target values ​​except the color target value corresponding to the target color initial value are equal to the color lower limit value K2. The target color initial value can be any color initial value among the first color initial value R, the second color initial value G and the third color initial value B.

[0128] For example, assume that the color upper limit value K1 is 255 and the color lower limit value K2 is 0. If the target color initial value is the first color initial value R, the driving circuit 10 can determine the first color target value R1=255, the second color target value G1=0, the third color target value B1=0, and the fourth color target value Y1=0.

[0129] If the target color value is the second color initial value G, the driving circuit 10 may determine the second color target value G1=255, the first color target value R1=0, the third color target value B1=0, and the fourth color target value Y1=0.

[0130] If the target color value is the third color initial value B, the driving circuit 10 may determine the third color target value B1=255, the first color target value R1=0, the second color target value G1=0, and the fourth color target value Y1=0.

[0131] In an embodiment of the present disclosure, if the color presented by a pixel in the projected image is pure red, pure green or pure blue, then the sum of the first color target value, the second color target value, the third color target value and the fourth color target value is equal to the sum of the first color initial value, the second color initial value and the third color initial value.

[0132] Step 406: Determine whether the first color target value, the second color target value, the third color target value, and the fourth color target value are all equal to the color upper limit value.

[0133] In the embodiment of the present disclosure, if it is determined that the first color initial value R, the second color initial value G, and the third color initial value B are all the color upper limit value K1, then the driving circuit 10 can determine that the first color target value R1 is equal to the color upper limit value K1, and R1=K1. Determine that the second color target value G1 is equal to the color upper limit value K1, and G1=K1. Determine that the third color target value B1 is equal to the color upper limit value K1, and B1=K1. And determine that the fourth color target value Y1 is equal to the color upper limit value K1, and Y1=K1.

[0134] For example, assuming that the color upper limit value K1 is 255, the first color initial value R, the second color initial value G and the third color initial value B are all the color upper limit value K1, then the driving circuit 10 can determine the first color target value R1=255, determine the second color target value G1=255, determine the third color target value B1=255, and determine the fourth color target value Y1=255.

[0135] Among them, if the color presented by the pixel in the projected image is pure white, the sum of the first color target value, the second color target value, the third color target value and the fourth color target value is greater than the sum of the first color initial value, the second color initial value and the third color initial value.

[0136] Step 407 : Control the light valve to flip according to the color of the light irradiated from the light source to the light valve, and the first color target value, the second color target value, the third color target value, and the fourth color target value of the pixel.

[0137] In the disclosed embodiment, the driving circuit 10 can control the flipping of the light valve according to the color of the light irradiated from the light source to the light valve, and the first color target value, the second color target value, the third color target value and the fourth color target value of the pixel.

[0138] Optionally, when the color of the light irradiated from the light source to the light valve is a first color, the driving circuit 10 can control the light valve to flip according to the first color target value of each pixel, and the first color is red, that is, the light irradiated from the light source 20 to the light valve 30 is red fluorescence r or red laser r. Figure 1After determining the first color target value R1 of each pixel in the projected image, the driving circuit 10 may send a driving signal to the light valve 30, and the driving signal may carry the first color target value R1 of each pixel. When the color of the light irradiated from the light source 20 to the light valve 30 is the first color, the light valve 30 may be flipped according to the first color target value R1 of each pixel.

[0139] The flipping time of the light valve 30 is positively correlated with the magnitude of the first color target value R1, and the illumination intensity of the red fluorescent light or the red laser light finally projected onto the projection screen is positively correlated with the magnitude of the first color target value R1. That is, the larger the first color target value R1, the longer the flipping time of the light valve 30, and accordingly, the higher the illumination intensity of the red fluorescent light r or the red laser light r finally projected onto the projection screen. By controlling the flipping time of the light valve 30 through the first color target value R1, the illumination intensity of the red fluorescent light r or the red laser light r finally projected onto the projection screen is controlled, thereby controlling the display intensity of the red component of each pixel in the projection image finally projected onto the projection screen.

[0140] The light valve 30 is integrated with multiple lenses, each lens corresponds to a pixel in the projected image, and the multiple lenses project the same color of light at the same time. When the light source irradiates the light valve, each lens can be flipped according to the first color target value R1 of the corresponding pixel, so as to project the red fluorescence r or red laser r of the corresponding pixel onto the projection screen.

[0141] refer to Figure 1 and Figure 2 The laser projection device may further include a laser driving assembly 40 connected to the driving assembly 10, a beam shaping assembly 50, a light combining assembly 60, a reflection assembly 70, a fluorescent wheel 80, a color filter wheel 90, a light rod 100, a lens assembly 110, a total internal reflection (TIR) ​​lens 120, a projection lens 130 and a projection screen 140.

[0142] The laser driving assembly 40 is connected to the light source 20, and the light source 20 is a blue laser. The reflecting assembly 70 may include a first reflecting mirror 701, a second reflecting mirror 702 and a third reflecting mirror 703. The light combining assembly 60 may be a dichroic film. The light rod 100 may also be called a light guide.

[0143] In the embodiment of the present disclosure, after receiving the image signal of the projected image, the driving circuit 10 can output an enable signal EN and a current control signal corresponding to the projected image, and transmit the enable signal and the current control signal to the laser driving component 40. Among them, the current control signal can be a pulse width modulation (PWM) signal. The laser driving component 40 can respond to the received enable signal EN and current control signal to provide a corresponding driving current to the blue laser connected thereto. The blue laser can emit light under the driving current provided by the laser driving component 40.

[0144] refer to Figure 2 The blue laser emitted by the light source 20 (i.e., the blue laser) is focused by the beam shaping component 50, reflected by the light combining component 60, and projected to the yellow phosphor area of ​​the fluorescent wheel 80 to stimulate yellow fluorescence. After being reflected by the metal substrate of the fluorescent wheel 80, the yellow fluorescence passes through the light combining component 60 again, and is filtered by the color filter wheel 90 to generate red fluorescence r. The red fluorescence r is homogenized by the light rod 100, and enters the TIR lens 120 after being shaped by the lens component 110. The red fluorescence r is irradiated to the light valve 30 after being totally reflected by the TIR lens 120. The light valve 30 is flipped according to the first color target value R1 of each pixel to reflect the red fluorescence r. After that, the red fluorescence r passes through the TIR lens 120 again, and is projected onto the projection screen 140 through the projection lens 140.

[0145] Optionally, when the color of the light irradiated to the light valve by the light source is a second color, the driving circuit 10 can control the light valve to flip according to the second color target value of each pixel. The second color is green, that is, the light irradiated to the light valve 30 by the light source 20 is green fluorescence g or green laser g. Figure 1 After determining the second color target value G1, the driving circuit 10 may send a driving signal to the light valve 30, and the driving signal may carry the second color target value G1 of each pixel. When the color of the light irradiated to the light valve 30 by the light source 20 is the second color, the light valve 30 may be flipped according to the second color target value G1 of each pixel.

[0146] The flipping time of the light valve 30 is positively correlated with the magnitude of the second color target value G1, and the illumination intensity of the green fluorescence or green laser finally projected onto the projection screen is positively correlated with the magnitude of the second color target value G1. That is, the larger the second color target value G1 is, the longer the flipping time of the light valve 30 is, and accordingly, the higher the illumination intensity of the green fluorescence g or green laser g finally projected onto the projection screen is. That is, by controlling the flipping time of the light valve 30 by the second color target value G1, the illumination intensity of the green fluorescence g or green laser g finally projected onto the projection screen is controlled, thereby controlling the display intensity of the green component of each pixel in the projection image finally projected onto the projection screen.

[0147] Optionally, when the light source irradiates the light valve, each lens may be flipped according to the second color target value G1 of the corresponding pixel, so as to project the green fluorescence g or green laser g of the corresponding pixel onto the projection screen.

[0148] refer to Figure 1 and Figure 2 The blue laser emitted by the light source 20 (blue laser) is focused by the beam shaping component 50, and after being reflected by the light combining component 60, it is projected onto the green phosphor area of ​​the fluorescent wheel 80 to stimulate green fluorescence. The green fluorescence is reflected by the metal substrate of the fluorescent wheel 80, passes through the light combining component 60 again, and is filtered by the color filter wheel 90 to generate green fluorescence g. The green fluorescence g is homogenized by the light rod 100, and enters the TIR lens 120 after being shaped by the lens component 110. The green fluorescence g is irradiated to the light valve 30 after being totally reflected by the TIR lens 120. The light valve 30 is flipped according to the second color target value G1 of each pixel to reflect the green fluorescence g. After that, the green fluorescence g passes through the TIR lens 120 again and is projected onto the projection screen 140 through the projection lens 130.

[0149] Optionally, when the color of the light irradiated from the light source to the light valve is the third color, the driving circuit 10 may control the light valve to flip according to the third color target value of each pixel. The third color is blue, that is, the light irradiated from the light source 20 to the light valve 30 is blue laser b. After determining the third color target value B1, the driving circuit 10 may send a driving signal to the light valve 30, and the driving signal may carry the second color target value B1 of each pixel. When the color of the light irradiated from the light source 20 to the light valve 30 is the third color, the light valve 30 may flip according to the third color target value B1 of each pixel.

[0150] The flipping time of the light valve 30 is positively correlated with the size of the third color target value B1, and the illumination intensity of the blue laser finally projected onto the projection screen is positively correlated with the size of the third color target value B1. That is, the larger the third color target value B1 is, the longer the flipping time of the light valve 30 is, and accordingly, the higher the illumination intensity of the blue laser finally projected onto the projection screen is. By controlling the flipping time of the light valve 30 through the third color target value B1, the illumination intensity of the blue laser finally projected onto the projection screen is controlled, and thus the display intensity of the blue component of each pixel in the projection image finally projected onto the projection screen is controlled.

[0151] Optionally, after the light source 20 irradiates the light valve 30 , each lens may be flipped according to the third color target value B1 of the corresponding pixel, so as to project the blue laser of the corresponding pixel onto the projection screen.

[0152] refer to Figure 1 and Figure 2 The blue laser emitted by the light source 20 (blue laser) is focused by the beam shaping component 50, reflected by the light combining component 60, passed through the transparent area of ​​the fluorescent wheel 80, reflected by the first reflector 701, the second reflector 702 and the third reflector 703 in sequence, reflected by the light combining component 60 again, and generated blue laser b by the transparent area of ​​the color filter wheel 90. The blue laser b is homogenized by the light rod 100, shaped by the lens component 110, and enters the TIR lens 120. The blue laser b is totally reflected by the TIR lens 120 and irradiated to the light valve 30, which flips according to the third color target value B1 of each pixel to reflect the blue laser b. After that, the blue laser b passes through the TIR lens 120 again and is projected onto the projection screen 140 through the projection lens 130.

[0153] Optionally, when the color of the light irradiated from the light source to the light valve is the fourth color, the driving circuit 10 can control the light valve to flip according to the fourth color target value of each pixel. The fourth color is yellow, that is, the light irradiated from the light source 20 to the light valve 30 is yellow fluorescence y. Figure 1 After determining the fourth color target value Y1, the driving circuit 10 may send a driving signal to the light valve 30, and the driving signal may carry the fourth color target value Y1 of each pixel. When the color of the light irradiated by the light source 20 to the light valve 30 is the fourth color, the light valve 30 may be flipped according to the fourth color target value Y1 of each pixel.

[0154] The flipping time of the light valve 30 is positively correlated with the size of the fourth color target value Y1, and the illumination intensity of the yellow fluorescence finally projected onto the projection screen is positively correlated with the size of the fourth color target value Y1. That is, the larger the fourth color target value Y1 is, the longer the flipping time of the light valve 30 is, and accordingly, the higher the illumination intensity of the yellow fluorescence finally projected onto the projection screen is. That is, by controlling the flipping time of the light valve 30 by the fourth color target value Y1, the illumination intensity of the yellow fluorescence finally projected onto the projection screen is controlled, and then the display intensity of the red component and the green component of each pixel in the projection image finally projected onto the projection screen is controlled.

[0155] Optionally, after the light source 20 irradiates the light valve 30 , each lens may be flipped according to the fourth color target value Y1 of the corresponding pixel, so as to project the yellow fluorescence y of the corresponding pixel onto the projection screen.

[0156] refer to Figure 1 and Figure 2 The blue laser emitted by the light source 20 (blue laser) is focused by the beam shaping component 50, reflected by the light combining component 60, and projected to the yellow phosphor area of ​​the fluorescent wheel 80 to stimulate yellow fluorescence. The yellow fluorescence is reflected by the metal substrate of the fluorescent wheel 80, passes through the light combining component 60 again, and generates yellow fluorescence y through the transparent area of ​​the color filter wheel 90. The yellow fluorescence y is homogenized by the light rod 100 and shaped by the lens component 110 before entering the TIR lens 120. The yellow fluorescence y is totally reflected by the TIR lens 120 and irradiated to the light valve 30. The light valve 30 flips according to the fourth color target value Y1 of each pixel to reflect the yellow fluorescence y. After that, the yellow fluorescence y passes through the TIR lens 120 again and is projected onto the projection screen 140 through the projection lens 130.

[0157] The red fluorescent light r, the green fluorescent light g, the blue laser light b and the yellow fluorescent light y are sequentially projected onto the projection screen 140 through the projection lens 130 , so that the projection image is displayed on the projection screen 140 .

[0158] In the embodiment of the present disclosure, by increasing the color light generated by the light source, the color target value corresponding to the four-color light is determined according to the color initial values ​​of the three colors of each pixel in the projected image, and the flipping duration of the light valve is controlled according to the color target value corresponding to the four-color light to control the cumulative time of the light source input into the projection lens, thereby realizing the use of the four-color light and the three colors of the image, thereby integrating the increased color light into the displayed projection image.

[0159] In the embodiment of the present disclosure, assuming that the frequency of the fluorescent wheel 80 and the color filter wheel 90 is H Hertz (HZ), then one cycle is T, where T= The rotation angle of the fluorescent wheel 80 and the color filter wheel 90 in one cycle is Y. When the light source 20 passes through the fluorescent wheel 80 and the color filter wheel 90 to generate red fluorescence r in one cycle, the maximum angle that the fluorescent wheel 80 and the color filter wheel 90 can rotate is the first angle y1. When the red fluorescence irradiates the light valve 30, the maximum flipping time of the light valve 30 is T1, and T1= It can be obtained that when the light valve 30 is flipped according to the first color target value R1, its flipping time is t1, and t1= × T1. The maximum flipping time T1 of the light valve 30 is positively correlated with the first angle y1.

[0160] For example, when the first color initial value R of a pixel in the image signal is 255, the second color initial value G is 0, and the third color initial value B is 0, that is, the pixel appears to be 100% pure red in the projected image, and the grayscale ratio is reduced year on year. The first angle y1 can be 80, at which time the light intensity of the red fluorescent light projected onto the projection screen is the highest.

[0161] When the light source 20 generates green fluorescence g through the fluorescent wheel 80 and the color filter wheel 90 in one cycle, the maximum angle that the fluorescent wheel 80 and the color filter wheel 90 can rotate is the second angle y2. When the green fluorescence g irradiates the light valve 30, the maximum flipping time of the light valve 30 is T2, where T2= It can be obtained that when the light valve 30 is flipped according to the second color target value G1, its flipping time is t2, where t2= × T2. The maximum flipping time T2 of the light valve 30 is positively correlated with the second angle y2.

[0162] For example, when the first color initial value R of a pixel in the image signal is 0, the second color initial value G is 255, and the third color initial value B is 0, that is, the pixel appears to be 100% pure green in the projected image, and the grayscale ratio is reduced year on year. The second angle y2 can be 120, at which time the light intensity of the green fluorescent light projected onto the projection screen is the highest.

[0163] When the light source 20 generates the blue laser b through the fluorescent wheel 80 and the color filter wheel 90 in one cycle, the maximum angle that the fluorescent wheel 80 and the color filter wheel 90 can rotate is the third angle y3. When the blue laser b irradiates the light valve 30, the maximum flipping time of the light valve 30 is T3, where T3= It can be obtained that when the light valve 30 is flipped according to the third color target value B1, its flipping time is t3, where t3= × T3. The maximum flipping time T3 of the light valve 30 is positively correlated with the third angle y3.

[0164] For example, when the first color initial value R of a pixel in the image signal is 0, the second color initial value G is 0, and the third color initial value B is 255, that is, the pixel appears to be 100% pure blue in the projected image, and the third angle y3 can be 60 degrees according to the grayscale ratio.

[0165] When the light source 20 generates yellow fluorescence y through the fluorescent wheel 80 and the color filter wheel 90 in one cycle, the maximum angle that the fluorescent wheel 80 and the color filter wheel 90 can rotate is the fourth angle y4. When the yellow fluorescence y irradiates the light valve 30, the maximum flipping time of the light valve 30 is T4, where T4= It can be obtained that when the light valve 30 is flipped according to the fourth color target value Y1, its flipping time is t4, and t4= ×T4. The maximum flipping time T4 of the light valve 30 is positively correlated with the fourth angle y4.

[0166] For example, when the first color initial value R of a pixel in the image signal is 255, the second color initial value G is 255, and the third color initial value B is 255, that is, the pixel appears to be 100% pure white in the projected image, and the fourth angle y4 can be 100 according to the grayscale ratio.

[0167] In the embodiment of the present disclosure, the first angle, the second angle, the third angle and the fourth angle can be set according to the material of the phosphor on the phosphor wheel and specific design requirements.

[0168] For example, assuming that the frequency of the fluorescent wheel and the color filter wheel is H=120HZ, that is, T=8.33 milliseconds (ms), the rotation angle of the fluorescent wheel 80 and the color filter wheel 90 in one cycle is Y=360 degrees, the first angle y1 is 80, the second angle y2 is 120, the third angle y3 is 60, the fourth angle y4 is 100, and the color upper limit value K1 is 255.

[0169] If the first color target value R1=0, when the red fluorescence r irradiates the light valve 30, the maximum flipping time T1 of the light valve 30= = ×8.33=1.85ms. It can be obtained that when the light valve 30 is flipped according to the first color target value R1, its flipping time is t1= ×T1= ×1.85=0ms.

[0170] If the second color target value G1=70, when the green fluorescence g irradiates the light valve 30, the maximum flipping time of the light valve 30 is T2= = ×8.33=2.78ms. It can be obtained that when the light valve 30 is flipped according to the second color target value G1, its flipping time is t2= ×T2= ×2.78=0.76ms.

[0171] If the third color target value B1=200, when the blue laser b irradiates the light valve 30, the maximum flipping time of the light valve 30 is T3= = ×8.33=1.39ms. It can be obtained that when the light valve 30 is flipped according to the third color target value B1, its flipping time is t3= ×T3= ×1.39=1.09ms.

[0172] If the fourth color target value Y1=200, when the yellow fluorescence y irradiates the light valve 30, the maximum flipping time of the light valve 30 is T4= = ×8.33=2.31ms. It can be obtained that when the light valve 30 is flipped according to the fourth color target value Y1, its flipping time is t4= ×T4= ×2.31=1.63ms.

[0173] It should be noted that the first threshold X1 is equal to the product of the tenth ratio N10 and the color upper limit K1, X1=N10×K1. The second threshold X2 is equal to the product of the eleventh ratio N11 and the color upper limit K1, X2=N11×K1.

[0174] The tenth ratio N10 is the ratio of the fourth angle y4 to the sum of the first angle y1 and the fourth angle y4. The eleventh ratio N11 is the ratio of the fourth angle y4 to the sum of the second angle y2 and the fourth angle y4, and N11= .

[0175] For example, assuming that the first angle y1 is 80, the second angle y2 is 120, the fourth angle y4 is 100, and the color upper limit value K1=255. Then the first threshold X1= ×255= ×255=141.7. The second threshold value X2= ×255= ×255=115.9.

[0176] It should be noted that in the above step 403, the third color target value B1 can also be equal to × K. In the first step 4044, the fourth color target value Y1 can also be equal to × K1. In the above step 4045, the fourth color target value Y1 can also be equal to ×K1.

[0177] It should be noted that the order of the steps of the laser projection method provided in the embodiment of the present disclosure can be appropriately adjusted, and the steps can also be deleted according to the situation. For example, step 402 and step 404 can be deleted according to the situation, or step 405 and step 406 can be deleted according to the situation, or any step of step 405 and step 406 can be deleted according to the situation, or step 4041 to step 4046 can be deleted. Any technician familiar with the technical field can easily think of a method of change within the technical scope disclosed in the present disclosure, which should be covered within the scope of protection of the present disclosure, so it will not be repeated.

[0178] In summary, the embodiment of the present disclosure provides a laser projection method, which can determine the first color target value, the second color target value, the third color target value and the fourth color target value of each pixel in the projected image according to the first color initial value, the second color initial value and the third color initial value of each pixel. And control the flipping of the light valve according to the color of the light irradiated by the light source to the light valve, and the first color target value, the second color target value, the third color target value and the fourth color target value of the pixel. The embodiment of the present disclosure increases the color light generated by the light source, determines the color target value corresponding to the four-color light according to the color initial values ​​of the three colors of each pixel in the projected image, and controls the flipping of the light valve according to the color target values ​​corresponding to the four-color light, thereby integrating the increased color light into the displayed projected image, which improves the brightness of the displayed image compared to the related art of only projecting three-color light to realize the display of the image.

[0179] refer to Figure 1 and Figure 2 The laser projection device includes: a driving circuit, a light source and a light valve. The driving circuit 10 is used to receive an image signal of a projected image, the image signal including a first color initial value, a second color initial value and a third color initial value of each pixel in the projected image.

[0180] The driving circuit 10 is also used to determine the first color target value, the second color target value, the third color target value and the fourth color target value of the pixel according to the first color initial value, the second color initial value and the third color initial value of each pixel, wherein the sum of the first color target value, the second color target value, the third color target value and the fourth color target value is greater than or equal to the sum of the first color initial value, the second color initial value and the third color initial value.

[0181] The driving circuit 10 is also used to control the flipping of the light valve according to the color of the light irradiated from the light source to the light valve, and the first color target value, the second color target value, the third color target value and the fourth color target value of the pixel.

[0182] Optionally, the driving circuit 10 is further used for:

[0183] If the first color initial value, the second color initial value, and the third color initial value do not satisfy the target condition, it is determined that the third color target value is equal to the third color initial value.

[0184] A first color target value, a second color target value, and a fourth color target value are determined according to the first color initial value and the second color initial value.

[0185] The target condition includes one or more of the following conditions:

[0186] The target color initial value among the first color initial value, the second color initial value and the third color initial value is the color upper limit value, and the other color initial values ​​except the target color initial value are the color lower limit values;

[0187] The first color initial value, the second color initial value, and the third color initial value are all color upper limit values.

[0188] Optionally, the driving circuit 10 is further used for:

[0189] It is respectively detected whether the first color initial value is greater than a first threshold value and whether the second color initial value is greater than a second threshold value.

[0190] If the initial value of the first color is greater than the first threshold and the initial value of the second color is less than or equal to the second threshold; or, the initial value of the first color is less than or equal to the first threshold and the initial value of the second color is greater than the second threshold; or, the initial value of the first color is less than or equal to the first threshold and the initial value of the second color is less than or equal to the second threshold, compare the first ratio with the second ratio.

[0191] If the first ratio is equal to the second ratio, the first color target value and the second color target value are both equal to the color lower limit value, and the fourth color target value is equal to the product of the third ratio and the color upper limit value;

[0192] Among them, the first ratio is the ratio of the first color initial value to the second color initial value, the second ratio is the ratio of the first threshold to the second threshold, the third ratio is the ratio of the first color initial value to the first threshold, or the third ratio is the ratio of the second color initial value to the second threshold.

[0193] Optionally, the driving circuit 10 is further used for:

[0194] After comparing the first ratio with the second ratio, if the first ratio is smaller than the second ratio, it is determined that the first color target value is equal to the color lower limit value.

[0195] The fourth color target value is determined to be equal to the product of a fourth ratio and the color upper limit value, and the fourth ratio is the ratio of the first color initial value to the first threshold value.

[0196] Determine that the second color target value is equal to the product of the fifth ratio and the color upper limit value, the fifth ratio is the ratio of the first difference to the second difference, the first difference is the difference between the second color initial value and the product of the fourth ratio and the second threshold value, and the second difference is the difference between the color upper limit value and the second threshold value.

[0197] Optionally, the driving circuit 10 is further used for:

[0198] After comparing the first ratio with the second ratio, if the first ratio is greater than the second ratio, it is determined that the second color target value is equal to the color lower limit value.

[0199] The fourth color target value is determined to be equal to the product of a sixth ratio and the color upper limit value, where the sixth ratio is the ratio of the second color initial value to the second threshold value.

[0200] Determine that the first color target value is equal to the product of the seventh ratio and the color upper limit value, the seventh ratio is the ratio of the third difference to the fourth difference, the third difference is the difference between the first color initial value and the product of the sixth ratio and the first threshold value, and the fourth difference is the difference between the color upper limit value and the first threshold value.

[0201] Optionally, the driving circuit 10 is further used for:

[0202] After respectively detecting whether the first color initial value is greater than the first threshold and whether the second color initial value is greater than the second threshold, if the first color initial value is greater than the first threshold and the second color initial value is greater than the second threshold, the fourth color target value is determined to be the color upper limit value.

[0203] Determine that the first color target value is equal to the product of the eighth ratio and the color upper limit value, the eighth ratio is the ratio of the difference between the first color initial value and the first threshold value to the fourth difference, and the fourth difference is the difference between the color upper limit value and the first threshold value.

[0204] Determine that the second color target value is equal to the product of the ninth ratio and the color upper limit value, the ninth ratio is the ratio of the difference between the second color initial value and the second threshold value to the second difference, and the second difference is the difference between the color upper limit value and the second threshold value.

[0205] Optionally, the driving circuit 10 is further used for:

[0206] When the first color initial value, the second color initial value and the third color initial value meet the target conditions, if the target color initial value among the first color initial value, the second color initial value and the third color initial value is the color upper limit value, and other color initial values ​​except the target color initial value are the color lower limit values, it is determined that the color target value corresponding to the target color initial value is equal to the color upper limit value, and it is determined that other color target values ​​except the color target value corresponding to the target color initial value are equal to the color lower limit value.

[0207] If the first color initial value, the second color initial value and the third color initial value are all color upper limit values, it is determined that the first color target value, the second color target value, the third color target value and the fourth color target value are all equal to the color upper limit value.

[0208] In summary, the embodiment of the present disclosure provides a laser projection device, which can determine the first color target value, the second color target value, the third color target value and the fourth color target value of each pixel in the projected image according to the first color initial value, the second color initial value and the third color initial value of each pixel. And control the flipping of the light valve according to the color of the light irradiated by the light source to the light valve, and the first color target value, the second color target value, the third color target value and the fourth color target value of the pixel. The embodiment of the present disclosure increases the color light generated by the light source, determines the color target value corresponding to the four-color light according to the color initial values ​​of the three colors of each pixel in the projected image, and controls the flipping of the light valve according to the color target values ​​corresponding to the four-color light, thereby integrating the increased color light into the displayed projected image, which improves the brightness of the displayed image compared to the related art of only projecting three-color light to realize the display of the image.

[0209] The above description is only an optional embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A laser projection device, characterized in that: include: A light source, wherein the light source is a blue laser; A fluorescent wheel, wherein the blue laser generated by the light source sequentially irradiates three different areas of the fluorescent wheel to generate yellow fluorescence, green fluorescence and blue laser; A color filter wheel, wherein the yellow fluorescence, green fluorescence and blue laser light sequentially pass through the color filter wheel to generate four-color light, wherein the four-color light includes red fluorescence, yellow fluorescence, green fluorescence and blue laser; A driving circuit, configured to receive an image signal of a projected image, the image signal comprising a first color initial value, a second color initial value and a third color initial value of each pixel in the projected image; and further configured to determine a first color target value, a second color target value, a third color target value and a fourth color target value of the pixel according to the first color initial value, the second color initial value and the third color initial value of each pixel, wherein the fourth color target value is determined by the first color initial value and the second color initial value; the first color is red, the second color is green, the third color is blue, and the fourth color is yellow; wherein the sum of the first color target value, the second color target value, the third color target value and the fourth color target value is greater than or equal to the sum of the first color initial value, the second color initial value and the third color initial value; and a light valve, the light valve being used to sequentially receive the illumination of the light of the first color, the second color, the third color and the fourth color, and being controlled to flip by the driving circuit according to the corresponding color target value; Wherein, the driving circuit is also used for: If the first color initial value, the second color initial value, and the third color initial value do not meet the target condition, determining that the third color target value is equal to the third color initial value; Determining the first color target value, the second color target value, and the fourth color target value according to the first color initial value and the second color initial value; The target conditions include one or more of the following conditions: The target color initial value among the first color initial value, the second color initial value and the third color initial value is a color upper limit value, and other color initial values ​​except the target color initial value are color lower limit values; The first color initial value, the second color initial value and the third color initial value are all the color upper limit values; And, the driving circuit is further used for: respectively detecting whether the first color initial value is greater than a first threshold value, and whether the second color initial value is greater than a second threshold value; If the first color initial value is greater than the first threshold, and the second color initial value is less than or equal to the second threshold; or, the first color initial value is less than or equal to the first threshold, and the second color initial value is greater than the second threshold; or, the first color initial value is less than or equal to the first threshold, and the second color initial value is less than or equal to the second threshold, compare the first ratio with the second ratio; If the first ratio is equal to the second ratio, determining that the first color target value and the second color target value are both equal to the color lower limit value, and determining that the fourth color target value is equal to the product of the third ratio and the color upper limit value; The first ratio is the ratio of the first color initial value to the second color initial value, and the second ratio is the ratio of the first threshold to the second threshold. The third ratio is a ratio of the first color initial value to the first threshold, or the third ratio is a ratio of the second color initial value to the second threshold.

2. The laser projection device according to claim 1, characterized in that: If the color presented by the pixel in the projected image is one of the first color, the second color, and the third color, then the sum of the first color target value, the second color target value, the third color target value, and the fourth color target value is equal to the sum of the first color initial value, the second color initial value, and the third color initial value.

3. The laser projection device according to claim 1, characterized in that: If the color presented by the pixel in the projected image is pure white, the sum of the first color target value, the second color target value, the third color target value and the fourth color target value is greater than the sum of the first color initial value, the second color initial value and the third color initial value.

4. The laser projection device according to claim 1, characterized in that: When the light source passes through the fluorescent wheel and the color filter wheel to generate yellow fluorescence, red fluorescence, and green fluorescence respectively in one cycle, the maximum angles that the fluorescent wheel and the color filter wheel can rotate are the fourth angle y4, the first angle y1, and the second angle y2 respectively. The first threshold value X1= *K1, the second threshold value X2= *K1, where K1 is the upper limit of the color.

5. The laser projection device according to claim 4, characterized in that: The first threshold value X1 and the second threshold value X2 are fixed values ​​pre-stored in the driving circuit. The first threshold value X1 represents the limit value of the initial color value of red light that can be expressed by the color target value of yellow light, and the second threshold value X2 represents the limit value of the initial color value of green light that can be expressed by the color target value of yellow light.

6. The laser projection device according to any one of claims 1 to 5, characterized in that: The driving circuit is a digital light processing driving chip, The driving signal sent by the driving circuit to the light valve carries the first color target value, the second color target value, the third color target value and the fourth color target value of each pixel. The light valve is a DMD, including a plurality of lenses, each lens corresponding to a pixel in the projected image, and each lens is flipped according to the color target value of the corresponding pixel. The flipping time of the light valve is positively correlated with the size of the corresponding color target value.

7. The laser projection device according to any one of claims 1 to 6, characterized in that: The laser projection device also includes: the driving circuit is also used to output an enable signal and a current control signal corresponding to the projection image after receiving the image signal of the projection image, and transmit the enable signal and the current control signal to the laser driving component, and the laser driving component is used to respond to the received enable signal and current control signal to provide a corresponding driving current to the blue laser connected thereto.

Images