CN111343442B

CN111343442B - Laser projection method and apparatus

Info

Publication number: CN111343442B
Application number: CN202010156634.1A
Authority: CN
Inventors: 李旭亮; 李泽广
Original assignee: Qingdao Hisense Laser Display Co Ltd
Current assignee: Qingdao Hisense Laser Display Co Ltd
Priority date: 2020-03-09
Filing date: 2020-03-09
Publication date: 2022-09-06
Anticipated expiration: 2040-03-09
Also published as: CN111343442A; CN115767055A; CN115720262A

Abstract

The application discloses a laser projection method and device, and belongs to the field of laser projection. The method comprises the following steps: receiving an image signal of a projected image; determining 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; and controlling the light valve to turn according to the color of the light irradiated to the light valve by the light source 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. Due to the fact that the color light generated by the light source can be increased and the color light generated by the increased light source is fused into the displayed projection image, the brightness of the displayed image is improved.

Description

Laser projection method and apparatus

Technical Field

The present disclosure relates to the field of laser projection, and in particular, to a laser projection method and apparatus.

Background

Currently, laser projection devices may include drive circuitry, a blue laser, a fluorescent wheel (or also referred to as a color filter wheel), a light valve, and a projection lens. In the process of projection display of an image to be projected, blue laser emitted by the blue laser is irradiated onto different areas of the fluorescent wheel in a time sequence, so that three color lights are generated, and the three color lights can comprise blue light, red light and green light. The driving circuit can receive an image signal of an image to be projected, which is sent by a front-end device (such as a computer), and the image signal comprises a red value, a green value and a blue value of each pixel in the image to be projected. The driving circuit can then control the light valve to flip according to the color of the light irradiated to the light valve by the light source and the red value, the green value and the blue value of the pixel. The light valve can modulate the light of each color into an image beam and transmit the image beam to the projection lens, thereby realizing the display of an image.

However, since only three color lights are projected to realize the display of the image, the luminance of the displayed image is low.

Disclosure of Invention

The embodiment of the disclosure provides a laser projection method and device, which can solve the problem that the brightness of a displayed image is low because only three-color light is projected to realize the display of the image in the related art. The technical scheme is as follows:

in one aspect, a laser projection method is provided, which is applied to a driving circuit of a laser projection apparatus, and the laser projection apparatus further includes: a light source and a light valve, the method comprising:

receiving an image signal of a projected image, wherein the image signal comprises a first color initial value, a second color initial value and a third color initial value of each pixel in the projected image;

determining a first color target value, a second color target value, a third color target value and a fourth color target value for each of the pixels based on a first color initial value, a second color initial value and a third color initial value for the pixel, wherein a 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 a sum of the first color initial value, the second color initial value and the third color initial value;

and controlling the light valve to turn according to the color of the light irradiated to the light valve by the light source 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.

Optionally, the determining the first color target value, the second color target value, the third color target value and the 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 the pixel includes:

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;

wherein the target conditions include one or more of the following conditions:

a 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 the 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 the color upper limit values.

Optionally, the 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:

respectively detecting whether the first color initial value is larger than a first threshold value and whether the second color initial value is larger than a second threshold value;

if the first color initial value is larger than the first threshold value, and the second color initial value is smaller than or equal to the second threshold value; 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, and comparing 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;

wherein the first ratio is a ratio of the first color initial value to the second color initial value, the second ratio is a ratio of the first threshold to the second threshold, and 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.

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

determining that the first color target value is equal to the color lower limit value;

determining that the fourth color target value is equal to a product of a fourth ratio, which is a ratio of the first color initial value to the first threshold value, and the color upper limit value;

determining that the second color target value is equal to a product of a fifth ratio and the color upper limit value, where the fifth ratio is a ratio of a first difference and a second difference, the first difference is a difference between the second color initial value and a product of the fourth ratio and the second threshold value, and the second difference is a difference between the color upper limit value and the second threshold value.

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

determining that the second color target value is equal to the color lower limit value;

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

determining that the first color target value is equal to a product of a seventh ratio and the color upper limit value, where the seventh ratio is a ratio of a third difference and a fourth difference, the third difference is a difference between the first color initial value and a product of the sixth ratio and the first threshold value, and the fourth difference is a difference between the color upper limit value and the first threshold value.

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

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 as the color upper limit value;

determining that the first color target value is equal to a product of an eighth ratio and the color upper limit value, where the eighth ratio is a ratio of a difference between the first color initial value and the first threshold value and a fourth difference, and the fourth difference is a difference between the color upper limit value and the first threshold value;

determining that the second color target value is equal to a product of a ninth ratio and the color upper limit value, where the ninth ratio is a ratio of a difference between the second color initial value and the second threshold value and a second difference, and the second difference is a difference between the color upper limit value and the second threshold value.

Optionally, if the first color initial value, the second color initial value, and the third color initial value satisfy the target condition, the method further includes:

if a target color initial value of 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, determining that a color target value corresponding to the target color initial value is equal to the color upper limit value, and determining that other color target values except the color target value corresponding to the target color initial value are equal to the color lower limit values;

if the first color initial value, the second color initial value, and the third color initial value are 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 values.

In another aspect, a laser projection apparatus is provided, which includes: a driving circuit, a light source and a light valve;

the driving circuit is used for receiving an image signal of a projected image, wherein the image signal comprises a first color initial value, a second color initial value and a third color initial value of each pixel in the projected image;

the driving circuit is 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 each of the pixels according to the first color initial value, the second color initial value and the third color initial value of the pixel, wherein a 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 a sum of the first color initial value, the second color initial value and the third color initial value;

the driving circuit is further configured to control the light valve to flip according to the color of the light irradiated to the light valve by the light source, 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.

Optionally, the driving circuit is further configured to:

wherein the target conditions include one or more of the following conditions:

Optionally, the driving circuit is further configured to:

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 larger than the first threshold value, and the second color initial value is smaller than or equal to the second threshold value; or the first color initial value is less than or equal to the first threshold value, and the second color initial value is greater than the second threshold value; 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, and comparing the first ratio with the second ratio;

if the first ratio is equal to the second ratio, determining that the first color target value is equal to the color lower limit value, determining that the second color target value is 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 beneficial effects brought by the technical scheme provided by the embodiment of the disclosure at least comprise:

the disclosed embodiments provide a laser projection method and apparatus, which may 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 in a projected image according to a first color initial value, a second color initial value, and a third color initial value of the pixel. And controlling the light valve to turn over according to the color of the light irradiated to the light valve by the light source 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 disclosure determines the color target value corresponding to the four color lights according to the color initial values of the three colors of each pixel in the projected image by increasing the color lights generated by the light source, and controls the light valve to turn over according to the color target value corresponding to the four color lights, so that the increased color lights are merged into the displayed projected image.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a laser projection apparatus provided in an embodiment of the present disclosure;

FIG. 2 is a schematic structural diagram of another laser projection apparatus provided in the embodiments of the present disclosure;

fig. 3 is a flowchart of a laser projection method provided by an embodiment of the present disclosure;

FIG. 4 is a flow chart of another laser projection method provided by embodiments of the present disclosure;

fig. 5 is 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 according to an embodiment of the present disclosure.

Detailed Description

To make the objects, technical solutions and advantages of the present disclosure more apparent, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

Fig. 1 and fig. 2 are schematic structural diagrams of a laser projection apparatus provided in an embodiment of the present disclosure. As shown in fig. 1 and 2, the laser projection apparatus may include a driving circuit 10, a light source 20, and a light valve 30.

The driving circuit 10 may be a Digital Light Processing (DLP) driving chip. The light source 20 may be a laser light source, which may comprise a blue laser, for example. 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).

Referring to fig. 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 to generate three colors of light (the three colors of light may include yellow fluorescent light, green fluorescent light, and blue laser), which are sequentially irradiated onto the light valve 30 through the color filter wheel 90 to generate four colors of light.

Fig. 3 is a flowchart of a laser projection method provided by an embodiment of the present disclosure. The laser projection method may be applied to the driving circuit 10 of the laser projection apparatus shown in fig. 1 and 2, which may further include a light source 20 and a light valve 30. As shown in fig. 3, the method may include:

step 301, receiving an image signal of a projected image.

Wherein the image signal may include a first color initial value, a second color initial value, and a third color initial value for 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.

Alternatively, 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 denoted by R, the second color initial value may be denoted by G, and the third color initial value may be denoted 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.

Referring to fig. 1, the driving circuit 10 may be connected to a front-end device 00, when the laser projection device performs projection display on the projection image, the front-end device 00 may transmit an image signal of the projection image to the driving circuit 10, and accordingly, the driving circuit 10 may receive the image signal of the projection image transmitted by the front-end device 00. Optionally, the front-end device 00 may be a computer.

Step 302, determining 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.

Alternatively, the fourth color may be yellow. The first color target value may be denoted by R1, the second color target value may be denoted by G1, the third color target value may be denoted by B1, and the fourth color target value may be denoted by Y1.

Step 303, controlling the light valve to turn over according to the color of the light irradiated to the light valve by the light source 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.

In the embodiment of the disclosure, when the color of the light irradiated to the light valve by the light source is the first color, the driving circuit 10 may control the light valve to flip according to the first color target value of each pixel. The first color may be red, that is, the light irradiated to the light valve 30 by the light source 20 is red fluorescent light or red laser light. 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 to the light valve 30 by the light source 20 is red.

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

When the color of the light irradiated to the light valve by the light source 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. Alternatively, the second color may be green, that is, the light source 20 irradiates the light valve 30 with green fluorescent light or green laser, and 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 light source 20 irradiates the light valve 30 with green color.

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

When the color of the light irradiated to the light valve by the light source 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. Alternatively, the third color may be blue, that is, the light source 20 irradiates the light valve 30 with blue laser, and 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 light source 20 irradiates the light valve 30 with blue color.

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

When the color of the light irradiated to the light valve by the light source 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. Alternatively, the fourth color may be yellow, that is, the light source 20 irradiates the light valve 30 with yellow light, and after determining the fourth color target value, when the color of the light source 20 irradiates the light valve 30 with yellow, the driving circuit 10 controls the light valve 30 to invert according to the fourth color target value B1 of each pixel.

The flipping time of the light valve 30 is positively correlated to 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 to the size of the fourth color target value Y1.

In summary, the embodiments of the present disclosure provide a laser projection method that may 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 in a projected image according to a first color initial value, a second color initial value, and a third color initial value of the pixel. And controlling the light valve to turn over according to the color of the light irradiated to the light valve by the light source 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 disclosure determines the color target value corresponding to the four color lights according to the color initial values of the three colors of each pixel in the projected image by increasing the color lights generated by the light source, and controls the light valve to turn over according to the color target value corresponding to the four color lights, so that the increased color lights are merged into the displayed projected image.

Fig. 4 is a flowchart of another laser projection method provided by the embodiments of the present disclosure. The laser projection method may be applied to the driving circuit 10 of the laser projection apparatus shown in fig. 1 and 2, which may further include a light source 20 and a light valve 30. As shown in fig. 4, the method may include:

step 401, receiving an image signal of a projected image.

Wherein 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. Alternatively, 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.

The first color is red, the second color is green, and the third color is blue. The first color initial value may be denoted by R, the second color initial value may be denoted by G, and the third color initial value may be denoted 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.

Referring to fig. 1, the driving circuit 10 may be connected to a front-end device 00, when the laser projection device performs projection display on the projection image, the front-end device 00 may transmit an image signal of the projection image to the driving circuit 10, and accordingly, the driving circuit 10 may receive the image signal of the projection image transmitted by the front-end device 00. For example, the front-end device may be a computer.

Step 402, detecting whether the first color initial value, the second color initial value and the third color initial value meet the target condition.

In the embodiment of the present disclosure, after receiving an image signal of a projected image, the driving circuit 10 may 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 satisfy a target condition, and if the first color initial value R, the second color initial value G, and the third color initial value B do not satisfy the target condition, which indicates that a color presented in the projected image by the pixel is not a pure color, 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 satisfy the target condition, indicating that the color presented by the pixel in the projection image is a pure color, step 405 and step 406 may be executed.

Wherein the target conditions may include one or more of the following conditions:

(1) and a 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 the other color initial values except the target color initial value are color lower limit values. Alternatively, the color upper limit value K1 may be 255, and the color lower limit value K2 may be 0.

For example, if the target color value is a first color initial value R, i.e., 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 projection image is 100% pure red.

If the target color value is the second color initial value G, i.e., the second color initial value G may 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.

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

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

For example, if the first color initial value R of the 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 of the pixel appearing in the projection image is 100% pure white.

Step 403 determines that the third color target value is equal to the third color initial value.

In the present disclosed embodiment, the drive circuit 10 may determine that the third color target value B1 is equal to the third color initial value B, B1 ═ B, after determining that the first color initial value R, the second color initial value G, and the third color initial value B do not satisfy the target condition. For example, if the third color initial value B is 200, it may be determined that the third color target value B1 is 200.

Step 404 determines a first color target value, a second color target value and a fourth color target value based on the first color initial value and the second color initial value.

In the embodiment of the present disclosure, the driving circuit 10 may 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 after determining that the first color initial value R, the second color initial value G and the third color initial value B do not satisfy the target condition. Wherein the fourth color may be yellow and the fourth color value may be represented by Y1. Since the red and green lights are mixed to be yellow light, the color target value of the red fluorescence and the color target value of the green light can be expressed by the color target value of the yellow light. The red light may be red fluorescence or red laser light. The green light may be green fluorescence or green laser. The yellow light may be yellow fluorescence.

Optionally, as shown in fig. 5, this step 404 may include:

step 4041, it is detected whether the first color initial value is greater than a first threshold, and whether the second color initial value is greater than a second threshold, respectively.

In the embodiment of the present disclosure, the driving circuit 10 may detect whether 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, respectively, after determining that the first color initial value R, the second color initial value G, and the third color initial value B do not satisfy the target condition. If the first color initial value R is greater than the first threshold X1, and the second color initial value G is less than or equal to the second threshold X2. Alternatively, the first color initial value R is equal to or less than the first threshold value X1, and the second color initial value G is greater than the second threshold value X2. Alternatively, if 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, 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, step 4047 may be executed.

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 indicates a limit value of an initial color value of red light that can be expressed as a color target value of yellow light. The second threshold value X2 represents a limit value of an initial color value of green light that can be expressed by the color target value of yellow light.

For example, the first threshold X1 may be 141.7 and the second threshold X2 may be 115.9.

Step 4042, compare the first ratio to the second ratio.

The drive circuit may compare the first ratio N1 with the second ratio N2 upon determining 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 either. If the first ratio N1 is equal to the second ratio N2, indicating 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, step 4043 may be executed. If the first ratio N1 is smaller 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. Step 4044 may be performed. If the first ratio N1 is greater than the second ratio N2, indicating that the target value of the yellow color is able to fully express the second initial color value G, but unable to fully express the first initial color value R, step 4045 may be executed.

Wherein the first ratio N1 may be a first ratioRatio of initial color value R to initial second color value G, i.e.

The second ratio N2 is the ratio of the first threshold X1 and the second threshold X2, i.e. the ratio

For example, if the first threshold value X1 is 141.7 and the second threshold value X2 is 115.9, then

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

In the present disclosed embodiment, the drive circuit 10, when determining that the first ratio N1 is equal to the second ratio N2, may determine that the color target value of the yellow light may fully express the first color initial value R and the second color initial value G, and thus may determine that the first color target value R1 is equal to the color lower limit value K2, the R1 is equal to K2, the second color target value G1 is equal to the color lower limit value K2, the G1 is equal to K2, and the fourth color target value Y1 is equal to the third ratio N3 × color upper limit value K1, the Y1 is equal to N3 × K1.

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

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 X1 is 141.7, the second threshold X2 is 115.9, the color upper limit value K1 is 255, and the color lower limit value K2 is 0, the first ratio is

The second ratio

The third ratio

Since N1 is N2, the driving circuit 10 may determine that the first color target value R1 is 0, the second color target value G1 is 0, and the fourth color target value Y1 is N3 × 255 is 0.1 × 255 is 25.5. 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.

In the embodiment of the present disclosure, after determining that the first ratio N1 is smaller than the second ratio N2, the driving circuit 10 may determine that the color target value of the yellow light may fully express the first color initial value R, but may not fully express the second color initial value G. The drive circuit 10 may thus determine that the first color target value R1 is equal to the color lower limit value K2, the R1 being equal to 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, the Y1 being equal to N4 × K1, 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, the G1 being equal to N5 × K1.

Wherein the fourth ratio N4 is a ratio of the first color initial value R to a first threshold X1

The fifth ratio N5 is a ratio of a first difference d1 to a second difference d2, the first difference d1 is a difference between the second color initial value G and a product of a fourth ratio N4 and a second threshold X2, the second difference d2 is a difference between the color upper limit value K1 and the second threshold X2, and the third ratio N5 is a ratio of a first difference d1 to a second difference d2

The second difference d2 is a limit value of an initial color value of red light that can be expressed by a color target value of red light.

For example, assume that the initial value R of the first color is 100, and the second color isThe initial color value G is 120, the first threshold value X1 is 141.7, the second threshold value X2 is 115.9, the upper color limit value is 255, and the lower color limit value is 0, the driving circuit 10 can determine the first ratio

The second ratio

The fourth ratio

The fifth ratio

Since the first ratio N1-0.83 is smaller than the second ratio N2-1.2226, the drive circuit 10 may determine that the first color target value R1-0, determine that the fourth color target value Y1-N4 × 255-0.7057 × 255-180, and determine that the second color target value G1-N5 × K1-0.2747 × 255-70.

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.

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 may determine that the color target value of the yellow light may completely express the second color initial value G, but may not completely express the first color initial value R, determine that the second color target value G1 is the color lower limit value K2, where G1 is K2, determine that the fourth color target value Y1 is equal to the product of the sixth ratio N6 and the color upper limit value K1, determine that Y1 is N6 × K1, determine that the first color target value R1 is equal to the product of the seventh ratio N7 and the color upper limit value K1, and determine that R1 is N7 × K1.

Wherein the sixth ratio N6 is the ratio of the second color initial value G to the second threshold X2

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 X1, the fourth difference d4 is the difference between the color upper limit value K1 and the first threshold X1, and the fourth difference d4 is the difference between the color upper limit value K1 and the first threshold X1

Wherein the fourth difference value is a limit value of the initial value of the color of the green light that can be expressed by the color target value of the green light.

For example, assuming that the first color initial value R is 130, the second color initial value G is 100, the first threshold X1 is 141.7, the second threshold X2 is 115.9, the color upper limit value is 255, and the color lower limit value is 0, the driving circuit 10 may determine the first ratio

The second ratio

The sixth ratio

The seventh ratio

Since the first ratio N1-1.3 is greater than the second ratio N2-1.2226, the driving circuit 10 may 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.

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.

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 may determine 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 may determine that the fourth color target value Y1 is equal to the color upper limit value K1, where Y1 is equal to K1. It is determined that the first color target value R1 is equal to the product of the eighth ratio N8 and the color upper limit value K1, where R1 is N8 × K1. And determines that the second color target value G1 is equal to the product of the ninth ratio N9 and the color upper limit value K1, G1 — N9 × K1.

Wherein the eighth ratio N8 is a ratio of a difference between the first color initial value R and the first threshold X1 to a fourth difference d4

The ninth ratio N9 is the ratio of the difference between the second color initial value G and the second threshold X2 to the second difference d2

For example, assuming that the first color initial value R is 150, the second color initial value G is 120, the first threshold X1 is 141.7, the second threshold X2 is 115.9, the color upper limit value K1 is 255, and the color lower limit value K2 is 0, the eighth ratio is

The ninth ratio

Since the first color initial value R-150 is greater than the second color initial value G-120, the driving circuit 10 may 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.

In the disclosed embodiment, after color blending, 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.

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 may determine that the first color target value R1 is 19, the second color target value G1 is 2, the third color target value B1 is 200, and the fourth color target value Y1 is 255 by executing the above steps 403 and 404, that the R1+ G1+ B1+ Y1 is 19+2+200+255 is 476, that the R + G + B is 150+120+200 + 470, and that the R1+ G1+ B1+ Y1> R + G + B because the 476 is greater than 470.

Step 405 determines that the target color value corresponding to the target color initial value is equal to the upper color limit value, and determines that the target color values other than the target color value corresponding to the target color initial value are equal to the lower color limit value.

In the embodiment of the present disclosure, if it is determined that a target color initial value among the first, second, and third color initial values R, G, and B is a color upper limit value, and the other color initial values than the target color initial value are color lower limit values, the drive circuit 10 may determine that a color target value corresponding to the target color initial value is equal to the color upper limit value K1, and determine that color target values other than 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 may be any one of the first color initial value R, the second color initial value G, and the third color initial value B.

For example, it is assumed 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 drive circuit 10 may determine that the first color target value R1 is 255, that the second color target value G1 is 0, that the third color target value B1 is 0, and that the fourth color target value Y1 is 0.

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

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

In the embodiment of the present disclosure, if the color presented by the pixel in the projection image is pure red, pure green or pure blue, 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.

Step 406, determining 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.

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, the driving circuit 10 may determine that the first color target value R1 is equal to the color upper limit value K1, and the R1 is equal to K1. It is determined that the second color target value G1 is equal to the color upper limit value K1, G1 being K1. It is determined that the third color target value B1 is equal to the color upper limit value K1, B1 being K1. And determines that the fourth color target value Y1 is equal to the color upper limit value K1, Y1 being K1.

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

If the color of the pixel in the projection 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 larger than the sum of the first color initial value, the second color initial value and the third color initial value.

Step 407, controlling the light valve to turn according to the color of the light irradiated to the light valve by the light source, 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.

In the embodiment of the present disclosure, the driving circuit 10 may control the light valve to flip according to the color of the light irradiated to the light valve by the light source, 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.

Alternatively, when the color of the light irradiated to the light valve by the light source is the first color, the driving circuit 10 may control the light valve to flip according to the first color target value of each pixel, where the first color is red, that is, the light irradiated to the light valve 30 by the light source 20 is red fluorescence r or red laser r. Referring to fig. 1, after determining the first color target value R1 for each pixel in the projected image, the driving circuit 10 may send a driving signal to the light valve 30, which may carry the first color target value R1 for each pixel. When the color of the light irradiated to the light valve 30 by the light source 20 is the first color, the light valve 30 may be inverted according to the first color target value R1 of each pixel.

The turning time of the light valve 30 is positively correlated to the size of 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 to the size of the first color target value R1. That is, the larger the first color target value R1 is, the longer the turning time of the light valve 30 is, and accordingly, the higher the illumination intensity of the red fluorescent light R or the red laser light R finally projected to the projection screen is. The turning time of the light valve 30 is controlled by the first color target value R1 to control the illumination intensity of the red fluorescent light R or the red laser R finally projected onto the projection screen, and further control the display intensity of the red component of each pixel in the projection image finally projected onto the projection screen.

The light valve 30 has a plurality of mirrors integrated thereon, each mirror corresponding to a pixel in the projected image, the plurality of mirrors projecting the same color of light at the same time. After the light source irradiates the light valve, each lens may be flipped according to the first color target value R1 of the corresponding pixel, so as to project the red fluorescent light R or the red laser light R of the corresponding pixel onto the projection screen.

Referring to fig. 1 and 2, the laser projection apparatus 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 bar 100, a lens assembly 110, a Total Internal Reflection (TIR) lens 120, a projection lens 130, and a projection screen 140.

The laser driving assembly 40 is connected to the light source 20, and the light source 20 is a blue laser. The reflective assembly 70 may include a first mirror 701, a second mirror 702, and a third mirror 703. The light combining element 60 may be a dichroic sheet. The light bar 100 may also be referred to as a light pipe.

In the embodiment of the present disclosure, the driving circuit 10 may output an enable signal EN and a current control signal corresponding to the projected image after receiving the image signal of the projected image, and transmit the enable signal and the current control signal to the laser driving assembly 40. The current control signal may be a Pulse Width Modulation (PWM) signal. The laser drive component 40 may provide a corresponding drive current to the blue laser to which it is connected in response to the received enable signal EN and the current control signal. The blue laser may be driven to emit light by a drive current provided by the laser drive assembly 40.

Referring to fig. 2, the blue laser emitted from the light source 20 (i.e., blue laser) is condensed by the beam shaping assembly 50, reflected by the light combining assembly 60, and projected to the yellow phosphor region of the fluorescent wheel 80 to excite yellow fluorescence. The yellow fluorescent light is reflected by the metal substrate of the fluorescent wheel 80, passes through the light combining assembly 60 again, and is filtered by the color filter wheel 90 to generate red fluorescent light r. The red fluorescent light r is homogenized by the light bar 100 and shaped by the lens assembly 110 to enter the TIR lens 120. The red fluorescent light R is totally reflected by the TIR lens 120 and then illuminates the light valve 30, the light valve 30 is turned over according to the first color target value R1 of each pixel to reflect the red fluorescent light R, and then the red fluorescent light R passes through the TIR lens 120 again and is projected onto the projection screen 140 through the projection lens 140.

Alternatively, when the color of the light irradiated to the light valve by the light source 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. 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. Referring to fig. 1, the driving circuit 10, after determining the second color target value G1, may send a driving signal to the light valve 30, where the driving signal may carry the second color target value G1 for 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 inverted according to the second color target value G1 of each pixel.

The flipping time of the light valve 30 is positively correlated to the second color target value G1, and the illumination intensity of the green fluorescent light or the green laser finally projected onto the projection screen is positively correlated to the second color target value G1. That is, the larger the second color target value G1, the longer the light valve 30 is flipped over, and accordingly, the higher the illumination intensity of the green fluorescence G or the green laser G finally projected onto the projection screen. That is, the turning time of the light valve 30 is controlled by the second color target value G1 to control the illumination intensity of the green fluorescent light G or the green laser light G finally projected onto the projection screen, and further control the display intensity of the green component of each pixel in the projection image finally projected onto the projection screen.

Alternatively, after the light source irradiates the light valve, each mirror may be flipped according to the second color target value G1 of the corresponding pixel, so as to project the green fluorescence G or the green laser G of the corresponding pixel onto the projection screen.

Referring to fig. 1 and 2, the blue laser emitted from the light source 20 (blue laser) is condensed by the beam shaping assembly 50, reflected by the light combining assembly 60, and projected to the green phosphor region of the fluorescent wheel 80 to excite green fluorescence. The green fluorescence is reflected by the metal substrate of the fluorescent wheel 80, passes through the light combining assembly 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 bar 100 and shaped by the lens assembly 110 into the TIR lens 120. The green fluorescence g is totally reflected by the TIR lens 120 and then irradiated to the light valve 30. The light valve 30 is turned over according to the second color target value G1 of each pixel to reflect the green fluorescence G, and then the green fluorescence G is transmitted through the TIR lens 120 again and projected onto the projection screen 140 through the projection lens 130.

Alternatively, when the color of the light irradiated to the light valve by the light source 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, i.e. the light irradiated to the light valve 30 by the light source 20 is blue laser b. The driving circuit 10, after determining the third color target value B1, may send a driving signal to the light valve 30, which may carry the second color target value B1 for each pixel. When the color of the light irradiated to the light valve 30 by the light source 20 is the third color, the light valve 30 may be inverted according to the third color target value B1 of each pixel.

The turning time of the light valve 30 is positively correlated to the third color target value B1, and the illumination intensity of the blue laser finally projected onto the projection screen is positively correlated to the third color target value B1. I.e., the larger the third color target value B1, the longer the turning time of the light valve 30, and accordingly, the higher the illumination intensity of the blue laser finally projected onto the projection screen. The turning duration of the light valve 30 is controlled by the third color target value B1 to control the illumination intensity of the blue laser finally projected onto the projection screen, and further control the display intensity of the blue component of each pixel in the projection image finally projected onto the projection screen.

Alternatively, after the light source 20 irradiates the light valve 30, each mirror 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.

Referring to fig. 1 and 2, the blue laser emitted from the light source 20 (blue laser) is condensed by the beam shaping assembly 50, reflected by the light combining assembly 60, transmitted through the transparent region 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 assembly 60 again, and passes through the transparent region of the color filter wheel 90 to generate the blue laser b. The blue laser b is homogenized by the optical rod 100, shaped by the lens assembly 110 and enters the TIR lens 120. The blue laser B is totally reflected by the TIR lens 120 and then illuminates the light valve 30, and the light valve 30 is turned according to the third color target value B1 of each pixel to reflect the blue laser B. Then, the blue laser b passes through the TIR lens 120 again and is projected onto the projection screen 140 through the projection lens 130.

Alternatively, when the color of the light irradiated to the light valve by the light source is a fourth color, the driving circuit 10 may control the light valve to flip according to a fourth color target value of each pixel. The fourth color is yellow, i.e. the light irradiated to the light valve 30 by the light source 20 is yellow fluorescence y. Referring to fig. 1, the driving circuit 10, after determining the fourth color target value Y1, may send a driving signal to the light valve 30, where the driving signal may carry the fourth color target value Y1 for each pixel. When the color of the light irradiated to the light valve 30 by the light source 20 is the fourth color, the light valve 30 may be inverted according to the fourth color target value Y1 of each pixel.

The turning time of the light valve 30 is positively correlated to the size of the fourth color target value Y1, and the illumination intensity of the yellow fluorescent light finally projected onto the projection screen is positively correlated to the size of the fourth color target value Y1. That is, the larger the fourth color target value Y1, the longer the light valve 30 is flipped over, and accordingly, the higher the illumination intensity of the yellow fluorescent light finally projected to the projection screen. That is, the turning time of the light valve 30 is controlled by the fourth color target value Y1 to control the illumination intensity of the yellow fluorescent light finally projected onto the projection screen, and further control the display intensity of the red component and the green component of each pixel in the projection image finally projected onto the projection screen.

Alternatively, after the light source 20 irradiates the light valve 30, each mirror may be inverted 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.

Referring to fig. 1 and 2, the blue laser emitted from the light source 20 (blue laser) is condensed by the beam shaping component 50, reflected by the light combining component 60, and projected to the yellow phosphor region of the fluorescent wheel 80 to excite yellow fluorescence. The yellow fluorescent light is reflected by the metal substrate of the fluorescent wheel 80, passes through the light combining component 60 again, and generates yellow fluorescent light y through the transparent region of the color filter wheel 90. The yellow fluorescent light y is homogenized by the light bar 100 and shaped by the lens assembly 110 into the TIR lens 120. The yellow fluorescent light Y is totally reflected by the TIR lens 120 and then illuminates the light valve 30, the light valve 30 is turned over according to the fourth color target value Y1 of each pixel to reflect the yellow fluorescent light Y, and then the yellow fluorescent light Y is transmitted through the TIR lens 120 again and projected onto the projection screen 140 through the projection lens 130.

The red fluorescence r, the green fluorescence g, the blue laser b and the yellow fluorescence y are projected onto the projection screen 140 through the projection lens 130 in a time sequence, so as to display the projection image on the projection screen 140.

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 value of the three colors of each pixel in the projection image, and the turning duration of the light valve is controlled according to the color target value corresponding to the four color light, so as to control the accumulated time of the light source input into the projection lens, implement three color pairing of the four color light and the image, and thus fuse the increased color light into the displayed projection image.

In the disclosed embodiment, assuming that the frequency of the fluorescent wheel 80 and the color filter wheel 90 is H Hertz (HZ), one period is T, which is

The rotation angle of the fluorescent wheel 80 and the color filter wheel 90 in one cycle is Y. The maximum angle that the fluorescent wheel 80 and the color filter wheel 90 can rotate when the light source 20 generates the red fluorescent light r through the fluorescent wheel 80 and the color filter wheel 90 in one cycle is the first angle y 1. When the red fluorescence is irradiated to the light valve 30, the maximum flip duration of the light valve 30 is T1

It follows that the light valve 30, when flipped according to the first color target value R1, has a flipping duration t1, which is

Wherein, the maximum flipping duration T1 of the light valve 30 is positively correlated to the magnitude of the first angle y 1.

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 projection image, and is reduced proportionally according to the gray scale, the first angle y1 may be 80, and the illumination intensity of the projection screen of the red fluorescence is the highest.

When the light source 20 generates the green fluorescence g through the fluorescent wheel 80 and the color filter wheel 90 in one period, 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 is irradiated to the light valve 30, the maximum turning time of the light valve 30 is T2, and the light valve 30 is turned over for the maximum time period

It follows that the light valve 30, when flipped according to the second color target value G1, has a flipping duration t2, which is

Wherein, the maximum flipping time period T2 of the light valve 30 is positively correlated to the magnitude of the second angle y 2.

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 projection image, and is reduced proportionally according to the gray scale, the second angle y2 may be 120, and the illumination intensity of the green fluorescence projected to the projection screen is the highest.

When the light source 20 generates the blue laser b through the fluorescent wheel 80 and the color filter wheel 90 in one period, the maximum angle that the fluorescent wheel 80 and the color filter wheel 90 can rotate is a third angle y3, when the blue laser b is irradiated to the light valve 30, the maximum flip time of the light valve 30 is T3, and the light valve 30 is turned over for a predetermined time period

It follows that the light valve 30, when flipped according to the third color target value B1, has a flipping duration t3, which is

T3. Wherein, the maximum flipping time period T3 of the light valve 30 is positively correlated to the third angle y 3.

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, when the pixel appears in the projection image as 100% pure blue, the third angle y3 may be 60 according to the gray scale reduction ratio.

When the light source 20 generates the yellow fluorescent light y through the fluorescent wheel 80 and the color filter wheel 90 in one period, the maximum angle that the fluorescent wheel 80 and the color filter wheel 90 can rotate is a fourth angle y4, when the yellow fluorescent light y is irradiated to the light valve 30, the maximum turning time length of the light valve 30 is T4, and the light valve 30 is turned over for a predetermined time period

It is thus obtained that the light valve 30, when flipped over according to the fourth color target value Y1, has a flipping duration t4

The maximum flipping time T4 of the light valve 30 is positively correlated to the fourth angle y 4.

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 projection image, and is reduced proportionally according to the gray scale, the fourth angle y4 may be 100.

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

For example, it is assumed that the frequency H of the fluorescent wheel and the color filter wheel is 120HZ, i.e., T is 8.33 milliseconds (ms), the rotation angle of one period of the fluorescent wheel 80 and the color filter wheel 90 is Y is 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.

If the first color target value R1 is equal to 0, the maximum flipping time of the light valve 30 when the red fluorescence R is irradiated to the light valve 30

It follows that the light valve 30, when flipped according to the first color target value R1, has a flipping period of time

If the second color target value G1 is 70, the maximum flipping time of the light valve 30 when the green fluorescence G is irradiated to the light valve 30 is equal to

It follows that the light valve 30, when flipped according to the second color target value G1, has a flipping period of time

2.78＝0.76ms。

If the third color target value B1 is 200, the maximum turning time of the light valve 30 when the blue laser B is irradiated to the light valve 30 is set as

It follows that the light valve 30, when flipped according to the third color target value B1, has a flipping period of time

1.39＝1.09ms。

If the fourth color target value Y1 is 200, when the yellow fluorescence Y is irradiated to the light valve 30, the maximum flipping time of the light valve 30 is equal to

It follows that the light valve 30, when flipped according to the fourth color target value Y1, has a flipping period of time

2.31＝1.63ms。

Note that, the first threshold value X1 is equal to the product of a tenth ratio value N10 and a color upper limit value K1, where X1 is N10 × K1. The second threshold X2 is equal to the product of the eleventh ratio N11 and the color upper limit value K1, where X2 is N11 × K1.

Wherein the tenth ratio N10 is a 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

For example, assume 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 is 255. The first threshold value

The second threshold value

It should be noted that, in the step 403, the third color target value B1 may also be equal to

K. In the first above-mentioned step 4044, the fourth color target value Y1 may also be equal to

In step 4045, the fourth color target value Y1 may be equal to

It should be noted that the order of the steps of the laser projection method provided by the embodiment of the present disclosure may be appropriately adjusted, and the steps may also be deleted according to the situation. For example, step 402 and step 404 may be deleted as appropriate, or step 405 and step 406 may be deleted as appropriate, or any of step 405 and step 406 may be deleted as appropriate, or steps 4041 to 4046 may be deleted. Any method that can be easily conceived by one skilled in the art within the technical scope of the present disclosure shall be covered within the protection scope of the present disclosure, and thus, the detailed description thereof shall not be repeated.

Referring to fig. 1 and 2, the laser projection apparatus includes: drive circuitry, a light source, and a light valve. A driving circuit 10 for receiving 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.

The driving circuit 10 is 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 a 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 a sum of the first color initial value, the second color initial value and the third color initial value.

The driving circuit 10 is further configured to control the light valve to flip according to the color of the light irradiated to the light valve by the light source, 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.

Optionally, the driving circuit 10 is further configured to:

and 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.

A first color target value, a second color target value, and a fourth color target value are determined based on the first color initial value and the second color initial value.

Wherein the target conditions include one or more of the following conditions:

a target color initial value of the first color initial value, the second color initial value and the third color initial value is a color upper limit value, and the 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 color upper limit values.

Optionally, the driving circuit 10 is further configured to:

whether the first color initial value is larger than a first threshold value and whether the second color initial value is larger than a second threshold value are detected respectively.

If the first color initial value is larger than the first threshold value and the second color initial value is smaller than or equal to the second threshold value; or the first color initial value is less than or equal to a first threshold value, and the second color initial value is greater than a second threshold value; or the first color initial value is less than or equal to a first threshold value, the second color initial value is less than or equal to a second threshold value, and the first ratio and the second ratio are compared.

the first ratio is a ratio of the first color initial value to the second color initial value, the second ratio is a ratio of the first threshold value to the second threshold value, and the third ratio is a ratio of the first color initial value to the first threshold value, or the third ratio is a ratio of the second color initial value to the second threshold value.

Optionally, the driving circuit 10 is further configured to:

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.

Determining that the fourth color target value is equal to a product of a fourth ratio, which is a ratio of the first color initial value to the first threshold value, and the color upper limit value.

Determining that the second color target value is equal to a product of a fifth ratio and the color upper limit value, the fifth ratio being a ratio of a first difference value and a second difference value, the first difference value being a difference value between the second color initial value and a product of a fourth ratio and a second threshold value, the second difference value being a difference value between the color upper limit value and the second threshold value.

Optionally, the driving circuit 10 is further configured to:

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.

It is determined that the fourth color target value is equal to a product of a sixth ratio, which is a ratio of the second color initial value to the second threshold value, and the color upper limit value.

Determining that the first color target value is equal to a product of a seventh ratio and a color upper limit value, the seventh ratio being a ratio of a third difference and a fourth difference, the third difference being a difference between the first color initial value and a product of a sixth ratio and the first threshold value, and the fourth difference being a difference between the color upper limit value and the first threshold value.

Optionally, the driving circuit 10 is further configured to:

after detecting whether the first color initial value is greater than the first threshold and 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 as the color upper limit.

Determining that the first color target value is equal to a product of an eighth ratio and a color upper limit value, wherein the eighth ratio is a ratio of a difference value between the first color initial value and the first threshold value and a fourth difference value, and the fourth difference value is a difference value between the color upper limit value and the first threshold value.

Determining that the second color target value is equal to a product of a ninth ratio and a color upper limit value, wherein the ninth ratio is a ratio of a difference between the second color initial value and the second threshold value and a second difference, and the second difference is a difference between the color upper limit value and the second threshold value.

Optionally, the driving circuit 10 is further configured to:

when the first color initial value, the second color initial value and the third color initial value satisfy the target condition, if a target color initial value of 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, determining that a color target value corresponding to the target color initial value is equal to the color upper limit value, and determining 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.

And if the first color initial value, the second color initial value and the third color initial value are all color upper limit values, determining 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 values.

In summary, the embodiments of the present disclosure provide a laser projection apparatus that can 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 in a projected image according to a first color initial value, a second color initial value, and a third color initial value of the pixel. And controlling the light valve to turn over according to the color of the light irradiated to the light valve by the light source 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 disclosure determines the color target value corresponding to the four color lights according to the color initial values of the three colors of each pixel in the projected image by increasing the color lights generated by the light source, and controls the light valve to turn over according to the color target value corresponding to the four color lights, so that the increased color lights are merged into the displayed projected image.

The above description is intended to be exemplary only and not to limit the present disclosure, and any modification, equivalent replacement, or improvement made without departing from the spirit and scope of the present disclosure is to be considered as the same as the present disclosure.

Claims

1. A laser projection method, applied to a driving circuit of a laser projection apparatus, the laser projection apparatus further comprising: a light source and a light valve, the method comprising:

controlling the light valve to turn according to the color of the light irradiated to the light valve by the light source 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;

determining a first color target value, a second color target value, a third color target value and a fourth color target value of each of the pixels according to the first color initial value, the second color initial value and the third color initial value of the pixel, including:

wherein the target conditions include one or more of the following conditions:

the first color initial value, the second color initial value and the third color initial value are the color upper limit values;

the determining the first, second and fourth color target values from first and second color initial values of the pixel comprises:

2. The method of claim 1, wherein after comparing the first ratio to the second ratio, if the first ratio is less than the second ratio, the method further comprises:

determining that the second color target value is equal to a product of a fifth ratio and the color upper limit value, the fifth ratio being a ratio of a first difference and a second difference, the first difference being a difference between the second color initial value and a product of the fourth ratio and the second threshold value, and the second difference being a difference between the color upper limit value and the second threshold value.

3. The method of claim 1, wherein after comparing the first ratio to the second ratio, if the first ratio is greater than the second ratio, the method further comprises:

determining that the first color target value is equal to a product of a seventh ratio and the color upper limit value, the seventh ratio being a ratio of a third difference and a fourth difference, the third difference being a difference between the first color initial value and a product of the sixth ratio and the first threshold value, and the fourth difference being a difference between the color upper limit value and the first threshold value.

4. The method according to claim 1, wherein after detecting whether the first color initial value is greater than a first threshold value and the second color initial value is greater than a second threshold value, respectively, the method further comprises:

determining that the first color target value is equal to a product of an eighth ratio and the color upper limit value, wherein the eighth ratio is a ratio of a difference between the first color initial value and the first threshold value and a fourth difference, and the fourth difference is a difference between the color upper limit value and the first threshold value;

determining that the second color target value is equal to a product of a ninth ratio and the color upper limit value, where the ninth ratio is a ratio of a difference between the second color initial value and the second threshold value to a second difference, and the second difference is a difference between the color upper limit value and the second threshold value.

5. The method according to any one of claims 1 to 4, wherein if the first color initial value, the second color initial value, and the third color initial value satisfy the target condition, the method further comprises:

6. A laser projection device, characterized in that the laser projection device comprises: a driving circuit, a light source and a light valve;

the driving circuit is further configured to control the light valve to flip according to the color of the light irradiated to the light valve by the light source, 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 drive circuit is further configured to:

wherein the target conditions include one or more of the following conditions:

the drive circuit is further configured to: