WO2022141947A1

WO2022141947A1 - Optical projection machine and control method therefor, and projection device

Info

Publication number: WO2022141947A1
Application number: PCT/CN2021/087226
Authority: WO
Inventors: 卢增祥
Original assignee: 亿信科技发展有限公司
Priority date: 2020-12-31
Filing date: 2021-04-14
Publication date: 2022-07-07
Also published as: CN112817203B; CN112817203A

Abstract

An optical projection machine and a control method therefor, and a projection device. The optical projection machine comprises a display module (101) and a projection lens (102), wherein the projection lens (102) is arranged on a light-emission side of the display module (101); and the optical projection machine is parallel to and does not overlap with an optical axis (pp') of the projection lens (102) by means of configuring a central axis (oo') of the display module (101). During the projection process of the optical projection machine, each display pixel in the display module (101) corresponds to a display scanning path on a projection screen, each display scanning path corresponds to a plurality of scanning projection pixels, and the display scanning paths cover initial projection pixels and scanning projection pixels.

Description

Projector light machine and its control method, projection equipment

The present disclosure claims the priority of a Chinese patent application with application number 202011626148.8 filed with the Chinese Patent Office on December 31, 2020, the entire contents of which are incorporated herein by reference.

technical field

The embodiments of the present application relate to the technical field of projection equipment, for example, to a projector light machine, a control method thereof, and a projection equipment.

Background technique

In related technologies, most projectors use DLP (Digital Light Processing, digital light processing) technology or liquid crystal projection technology, wherein DLP technology is a digital micromirror device DMD (Digital Micromirror Device, digital micromirror mirror) developed by Texas Instruments. ) chip as an imaging device, a projection technology that realizes the projected image by adjusting the reflected light. The color effect of the DLP projector depends on the color wheel and the movement of the DMD chip. The single-chip DLP projection system adopts a reflective structure, especially in the low-end Among the products, the single-chip DLP projection system is slightly inferior to the three-primary-color mixed LCD (Liquid Crystal Display, liquid crystal display) projector in terms of image color reproduction, and the colors are not bright enough and vivid, and the color gamut is not enough. The basic principle of liquid crystal projection is to use the LCD liquid crystal module to modulate the color light emitted by the light source and projected onto the screen. In order to accurately project the color of the image, it is necessary to separate the color of the light source into three colors: R, G, and B. They are combined into one and projected on the screen using a projection lens, with low resolution and insufficient brightness.

In both cases, the pixels do not emit light, and the projection is performed by means of another light source illumination, that is, the projection light source and pixelization are realized in two parts, which will waste a lot of light energy in the re-graphic process, and the energy utilization rate is low.

There is also a laser scanning projector in the related art, such as microvision (laser micro projector), which uses strong laser fast and slow axis scanning projection, and the color and brightness are relatively good, but strong laser scanning will bring security problems, long time Scanning a little will cause the projection screen to be burnt out due to overheating, or cause damage to the human eye when looking directly at it.

SUMMARY OF THE INVENTION

The present application provides a light projector, a control method thereof, and a projection device, so as to realize high-brightness image projection during the projection process, and will not cause damage to human eyes when looking directly.

The embodiment of the first aspect of the present application proposes a light projector, including a display module and a projection lens, the projection lens is arranged on the light exit side of the display module, and the central axis of the display module is connected to the light of the projection lens. The axes are parallel and do not overlap;

The display module includes a plurality of display pixels, and each of the display pixels corresponds to an initial projection pixel on the projection screen. During the projection process of the light projector, the display module is configured to perform a scanning motion, and each of the display pixels corresponds to an initial projection pixel on the projection screen. The display pixels correspond to a display scan path on the projection screen, each of the display scan paths corresponds to a plurality of scan projection pixels, and the display scan paths cover the initial projection pixels and the scan projection pixels;

The plurality of display pixels include a first display pixel and a second display pixel. During the scanning motion of the display module, the direction of the first display pixel pointing to the second display pixel does not change.

The embodiment of the second aspect of the present application provides a control method for a light projector, which is applied to the light projector, including:

Controlling the display state of the display pixels according to the projection requirements; wherein, the display state includes the lighting time and display brightness of the display pixels;

During the projection process of the light projector, the display module is controlled to perform a scanning motion.

The embodiment of the third aspect of the present application provides a projection device, including at least two of the projectors; the projection device further includes:

an image acquisition unit configured to acquire projection images of at least two of the light projectors;

The control unit is configured to adjust the outgoing image of each of the light projectors according to the projected images of at least two of the light projectors.

Description of drawings

1 is a schematic structural diagram of a light projector proposed by an embodiment of the present application;

Fig. 2 is the projection image of the light projector proposed by the embodiment of the present application;

3 is a projection image of a light projector proposed by an embodiment of the present application;

4 is a projection image of a light projector proposed by another embodiment of the present application;

5 is a projection image of a light projector proposed by another embodiment of the present application;

6 is a schematic structural diagram of a light projector proposed by another embodiment of the present application;

7 is a schematic structural diagram of a light projector proposed by a specific embodiment of the present application;

8 is a schematic structural diagram of a light projector proposed by another embodiment of the present application;

9 is a schematic structural diagram of a light projector proposed by another specific embodiment of the present application;

10 is a flowchart of a control method of a light projector proposed by an embodiment of the present application;

11 is a projection image of a light projector in the control method of a light projector proposed by an embodiment of the present application;

12 is a projection image of a light projector in a method for controlling a light projector proposed by an embodiment of the present application;

13 is a projection image of a light projector in a method for controlling a light projector proposed by another embodiment of the present application;

FIG. 14 is a block diagram of a projection device proposed by an embodiment of the present application;

FIG. 15 is a projection image of a projection device proposed by an embodiment of the present application;

FIG. 16 is an optical path diagram of a projection device proposed by a specific embodiment of the present application.

Detailed ways

The present application will be described below with reference to the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present application. In addition, it should be noted that, for the convenience of description, the drawings only show some but not all the structures related to the present application.

FIG. 1 is a schematic structural diagram of an optical projector proposed by an embodiment of the present application. As shown in FIG. 1 , the projector includes a display module 101 and a projection lens 102. The projection lens 102 is disposed on the light-emitting side of the display module 101, and the central axis oo' of the display module 101 is parallel to the optical axis pp' of the projection lens 102. and do not overlap;

The display module 101 includes a plurality of display pixels, and each display pixel corresponds to an initial projection pixel on the projection screen 103. During the projection process of the light projector, the display module 101 scans and moves, and each display pixel corresponds to an initial projection pixel on the projection screen 103. Display scan paths, each display scan path corresponds to multiple scan projection pixels, and the display scan path covers the initial projection pixels and the scan projection pixels;

During the scanning motion of the display module 101 , the direction of the first display pixel in the display module 101 pointing to the second display pixel remains unchanged, and the first display pixel and the second display pixel are any two display pixels in the display module 101 .

It should be noted that the central axis oo' of the display module 101 is parallel to and does not overlap with the optical axis pp' of the projection lens 102, wherein, as shown in FIG. 1, the distance between oo' and pp' is H, which is understandable Yes, the value of H is greater than 0.

In the related art, the display module 101 includes a plurality of display pixels, and the aperture ratio of the plurality of display pixels is not 100%, and there is a gap between adjacent display pixels. The luminous surface is proportionally enlarged, resulting in too large pixel pitch of the picture and reduced resolution. The display module 101 performs a scanning motion, so that the display pixels of the display module 101 can correspond to a display scanning path on the projection screen 103, and each display scanning path corresponds to a plurality of scanning projection pixels, and the display scanning path covers the initial projection pixel and the scanning projection pixel. . Therefore, the display scanning path fills the interval between adjacent projected pixels, so that the resolution of the projected image is improved and the image quality is improved.

The value of H is greater than 0, which can ensure that the display pixels located on the central axis oo' in the display module 101 can also correspond to a display scanning path on the projection screen 103 during the projection process of the light projector to fill the gap between the projection pixels Therefore, when the display module 101 performs a scanning motion, each display pixel in the display module 101 can fill the spaced area between the projection pixels, thereby increasing the resolution and brightness of the projection image.

According to an embodiment of the present application, the scanning motion of the display module 101 includes at least one of linear scanning motion, circular scanning motion, elliptical scanning motion, figure-8 scanning motion and Lissajous figure scanning motion.

It can be understood that, during the above-mentioned scanning movement of the display module 101, the display scanning path of each display pixel in the display module 101 on the projection screen 103 is the image formed by the movement. For example, as shown in FIG. 2 , when the scanning motion of the display module 101 is linear scanning motion (eg, linear fast and slow axis scanning), the display scanning path of each display pixel on the projection screen 103 is, for example, a zigzag shape. When the scanning motion of the display module 101 is a circular scanning motion, the display scanning path of each display pixel on the projection screen 103 is a circle. It can be known that, when the scanning motion mode of the display module 101 is an elliptical scanning motion, the display scanning path of each display pixel on the projection screen 103 is an ellipse. When the scanning motion mode of the display module 101 is the 8-figure scanning motion, the display scanning path of each display pixel on the projection screen 103 is 8-figure. When the scanning motion of the display module 101 is a Lissajous figure scanning motion, the display scanning path of each display pixel on the projection screen 103 is a Lissajous figure.

In one embodiment, the arrangement of display pixels in the display module 101 may be an m*n array arrangement.

The following description will be given by taking an example that the display pixel arrangement in the display module 101 is an m*n array arrangement (where m=3, n=5), and the scanning motion is a circular scanning motion.

During the circular scanning motion of the display module 101 , the direction in which the first display pixel in the display module 101 points to the second display pixel remains unchanged, and the first display pixel and the second display pixel are any two display pixels in the display module 101 .

FIG. 3 is a projected image of a light projector proposed by an embodiment of the present application. As shown in FIG. 3, the circular scanning radius of the display module 101 is the distance H between the central axis oo' and the optical axis pp', wherein the direction of the first display pixel in the display module 101 pointing to the second display pixel is unchanged. The first projection pixel A in FIG. 3 is the first projection pixel A corresponding to the first display pixel when the display module 101 does not perform scanning motion, that is, the initial projection pixel position corresponding to the first display pixel. The second projection pixel B is the second projection pixel B corresponding to the second display pixel when the display module 101 does not perform scanning motion, that is, the initial projection pixel position corresponding to the second display pixel. That is to say, the display module 101 takes the optical axis pp' of the projection lens as the central axis and the radius is H to perform a translational circular motion. The display scanning path of the second display pixel in the display module 101 on the projection screen 103 is a circle with a radius of H, which is the curve 2, the display scanning path of the third display pixel on the projection screen 103 is the curve 1, and the fourth display pixel is the curve 1. The display scanning path on the projection screen 103 is curve 3, wherein the display scanning path of the third display pixel on the projection screen 103 covers part of the display scanning path curve 2 of the second display pixel on the projection screen 103, in other words, The partial curve 2 of the display scan path of the second display pixel on the projection screen 103 fills the area curve 1 defined by the display scan path of the third display pixel on the projection screen 103, so that the interval between the display pixels in the display module 101 is During the scanning motion of the display module 101, it is filled by the display scanning path of each other display pixel, thereby improving the resolution of the projected image.

It can be understood that, the larger the radius H of the display scanning path of the display module 101 is, the more the display scanning path of each display pixel is multiplexed. That is to say, the larger the radius H, the longer the perimeter of the display scanning path of each display pixel, and the longer the arc length of the display scanning path passing through the area except the initial position of each projected pixel, which contributes to filling the limited area of the display scanning path. The larger it is, the greater the contribution to the filling of the space between adjacent pixels. 4 is a projection image of the optical projector proposed by another embodiment of the present application; FIG. 5 is a projected image of the optical projector proposed by another embodiment of the present application. As shown in FIGS. 3 to 5 , the radius H1 of the circular scanning motion performed by the display module 101 in FIG. 4 is smaller than the radius H of the circular scanning motion performed by the display module 101 in FIG. 3 , and the radius H2 of the circular scanning motion performed by the display module 101 in FIG. 5 It is larger than the radius H of the circular scanning motion of the display module 101 in FIG. 3 . It can be seen from Figures 3 to 5 that the fifth and fourth curves both contribute to the interval between adjacent projected pixels, but the contribution is small, and the second curve fills the area defined by the first curve, The third curve does not fill the area defined by the first curve. Obviously, the contribution of the second curve and the first curve to the interval filling between adjacent projected pixels is greater than that of the fifth curve and the fourth curve in Figure 4. Space fill contribution between adjacent projected pixels. The contribution of the seventh curve and the eighth curve to the space filling between adjacent projected pixels is greater than the contribution of the second curve and the first curve to the space filling between adjacent projected pixels in FIG. 3 . In other words, the larger the radius H, the larger the contribution to the gap filling between adjacent projected pixels. The more pixels each display pixel forms on the projection screen, the more it contributes to filling the gap between adjacent projection pixels, that is, the more times it is multiplexed.

In the following example, the circular motion is still used as an example.

According to an embodiment of the present application, FIG. 6 is a schematic structural diagram of a light projector proposed by another embodiment of the present application. As shown in FIG. 6 , the display module 101 includes a display panel 1011; the central axis of the display panel 1011 is parallel to the optical axis of the projection lens 102 and does not overlap;

During the projection process of the light projector, the display panel 1011 moves.

According to an embodiment of the present application, the display panel 1011 includes a micro light emitting diode display panel, or a vertical cavity surface emitting laser display panel, or a quantum dot display panel.

It should be noted that the display panel 1011 is provided with a plurality of display pixels, the central axis qq' of the display panel 1011 makes a circular motion around the optical axis pp' of the projection lens 102, and the display panel 1011 includes a miniature light-emitting diode display panel, or a vertical cavity surface A laser-emitting display panel, or a quantum dot display panel, the display pixels included in the aforementioned display panel 1011 have high brightness, and the display panel 1011 performs a circular scanning motion, and the imaging trajectory of the display pixels on the display panel 1011 on the projection screen 103 is also a circle. , the imaging track can fill the interval between adjacent pixels, so that after the display pixels of the display panel 1011 pass through the projection lens 102, the image on the projection screen 103 also has high brightness, and will not hurt when the human eye looks directly human eye.

Taking the miniature LED display panel 1011 as an example, the resolution of the display panel 1011 is K*K, and the resolution of the two display panels 1011 is 2K*K, because the distance between the display pixels on the edge of the display panel and the edge of the display panel may not be able to be determined. For complete coverage, L pixels need to be subtracted, and finally, the resolution of the projection image of the display panel 1011 on the projection screen 103 is (2K-L)*N; (K-L)*N.

The value of L can be determined according to the distance between the central axis qq' of the display panel 1011 and the optical axis pp' of the projection lens 102. The difference between the central axis qq' of the display panel 1011 and the optical axis pp' of the projection lens 102 The larger the distance between the display pixels, the larger the area covered by the distance between the display pixels on the edge of the display panel and the edge of the display panel, and the smaller the value of L is. On the contrary, the central axis qq' of the display panel 1011 and the optical axis pp of the projector lens The smaller the space between ', the smaller the area covered by the interval between the display pixels at the edge of the display panel and the edge of the display panel, and the larger the value of L. In addition, the value of N satisfies the relationship N=π*D/P, where D is the diameter of the circular scanning motion of the central axis qq' of the display panel 1011 around the optical axis pp' of the projection lens 102, and P is the distance between adjacent display pixels. interval size.

In one embodiment, when K=192, L=30, and N=7, the final resolution of the projection image of the display panel 1101 on the projection screen 103 is 2478*1134. Among them, (384-30)*7=2478, (192-30)*7=1134. Among them, 7 is also the reciprocal of the aperture ratio of the display pixel of the display panel 1011, the size of the display pixel is 22um, the size of the light emitting surface of the display pixel is 3um*3um, and the aperture ratio of the display pixel is 3/22=13.6%. Therefore, the smaller the aperture ratio of the display pixels, the higher the resolution of the projected image projected onto the projection screen 103 and the better the image quality.

It can be understood that FIG. 7 is a schematic structural diagram of a light projector proposed by a specific embodiment of the present application. As shown in FIG. 7, in the actual installation process, the display panel 1011 can be installed on the gear or bearing 105, the motor 104 can be used to drive the display panel 1011 fixed on the gear or bearing 105 to move through the transmission device, or other In this way, the display panel 1011 is driven to perform a scanning motion. The movement of the display panel 1011 can accelerate the heat dissipation of the display panel 1011 .

According to an embodiment of the present application, FIG. 8 is a schematic structural diagram of a light projector proposed by another embodiment of the present application. As shown in FIG. 8, the display module 101 includes a display panel 1011 and a scanning lens 1012; the optical axis rr' of the scanning lens 1012 is parallel to and does not overlap with the optical axis pp' of the projection lens 103;

During the projection process of the light projector, the display panel 1011 is fixed, and the scanning lens 1012 scans and moves.

It should be noted that, in this embodiment, the central axis of the display panel 1011 may coincide with the optical axis of the projection lens 103 , so that the projection lens 102 can capture the light emitted from the display panel 1011 in a maximum range. The optical axis rr' of the scanning lens 1012 and the optical axis pp' of the projection lens 102 can be parallel and do not overlap, so as to ensure that the display scanning path of each display pixel in the display panel 1011 on the projection screen 103 can be filled with other display pixels. The area defined by the scanning path is displayed on the projection screen 103 to improve the resolution and brightness of the displayed image.

9 is a schematic structural diagram of a light projector proposed by another specific embodiment of the present application. As shown in FIG. 9, the scanning lens 1012 is installed on the hollow rotating shaft 110, the hollow rotating shaft 110 is installed on the fixed bearing 109, the motor 108 drives the gear or the transmission belt 107 to drive the hollow rotating shaft 110 to rotate, and then drives the scanning lens 1012 to move, The optical center of the scanning lens 1012 performs a circular scanning motion around the optical axis pp' of the projection lens 103, the direction between any two points on the scanning lens 1012 remains unchanged, and the display scanning path of the display pixels of the display panel 1011 on the projection screen 103 Therefore, the display scanning path of each display pixel on the projection screen 103 can cover the initial projection pixel and the scanning projection pixel, which improves the resolution and brightness of the projection image.

It can be understood that, when the hollow rotating shaft 110 rotates, a small fan blade can be installed on the edge of the hollow rotating shaft 110, and then the display panel 1011 can be dissipated during the scanning process of the scanning lens 1012.

According to an embodiment of the present application, the scanning lens 1012 is disposed in the optical path between the display panel 1011 and the projection lens 102;

Alternatively, the projection lens 102 includes a plurality of projection lenses, and the scanning lens 1012 is disposed in the optical path between any two adjacent projection lenses.

That is to say, the scanning lens 1012 may be provided separately, or may be integrated in the projection lens 102 .

According to an embodiment of the present application, the scanning lens 1012 includes a plurality of sub-scanning lenses arranged in an array.

To sum up, according to the light projector proposed in the embodiments of the present application, by setting the central axis of the display module and the optical axis of the projection lens to be parallel and not overlapping, each display pixel in the display module corresponds to an initial Projection pixel, in the projection process of the projector, each display pixel in the display module corresponds to a display scanning path on the projection screen, each display scanning path corresponds to a plurality of scanning projection pixels, and the display scanning path covers the initial projection pixel and the scanning path. Projection pixels. Thus, the resolution and image brightness of the projected image can be improved.

FIG. 10 is a flowchart of a control method for a light projector proposed by an embodiment of the present application. As shown in FIG. 10 , the light projector to which the control method of the light projector is applied includes:

S101, according to projection requirements, control the display state of the display pixels; the display state includes the lighting time and display brightness of the display pixels;

S102, the display module includes a plurality of display pixels, each display pixel corresponds to an initial projection pixel on the projection screen, during the projection process of the light projector, the display module performs a scanning motion, and each display pixel corresponds to a display pixel on the projection screen Scanning paths, each display scanning path corresponds to a plurality of scanning projection pixels, and the display scanning path covers the initial projection pixels and the scanning projection pixels.

Among them, the display module performs a scanning motion, and the circular motion is still taken as an example for description.

It can be known that the projection requirement refers to the projection image to be finally presented by the light projector on the projection screen. The display state of each display pixel in the display module is controlled according to the projection image to be finally presented on the projection screen, wherein the display state includes the lighting time and display brightness of the display pixel. Finally, the projection image to be presented on the projection screen will be pre-stored in the display module in advance.

For example, the final projection images to be displayed on the projection screen are triangles and rectangles in sequence, that is, after the display pixels in the display module pass through the projection lens, the final images formed on the projection screen are triangles and rectangles in sequence, then, first of all The display pixels in the display module at the position corresponding to the triangular image are controlled to light up, and then the display pixels in the display module at the position corresponding to the rectangular image are controlled to light up.

FIG. 11 is a projection image of a light projector in the control method of a light projector proposed by an embodiment of the present application; FIG. 12 is a projected image of a light projector in the control method of a light projector proposed by an embodiment of the present application. As shown in Figures 11 to 12, the black dots in Figure 11 are the imaging points of each display pixel of the display module on the projection screen when the display module does not perform scanning motion. In order to improve the resolution of the display screen, the display module is controlled to perform scanning motion , each display pixel corresponds to a display scan path on the projection screen, and each display scan path covers an area other than the initial projection position. Therefore, during the scanning motion of the display module, the spaced areas between adjacent pixels, such as the area F and the area G, are passed by the display scanning paths of other display pixels, so that the area F and the area G are lit up, and further, the display is improved. The resolution and brightness of the screen.

The projection requirement may be to light up an area surrounded by image points formed by the original display module without scanning motion on the screen. The following description will be given by taking the projection demand as an example that the area G is lit up. It can be understood that the fact that the area G is lit means that the area G is completely filled by the display scanning paths of other display pixels. In FIG. 12 , only three display scanning paths, namely, the curve 11, the curve 12, and the curve 13, pass through the area G. , which is only used as an example for illustration. During the actual operation, it can be adjusted according to the distance between the image points, the circular radius of the scanning motion of the display module, etc., so that the area G is completely filled by the display scanning paths of other display pixels.

It should be noted that when the projection requirement is only when the area G is lit, the display module only controls the display pixels whose display scanning path enters the area G to light up during the scanning motion, and controls the display pixels to turn off after the display scanning path passes through the area G. .

The following is a detailed description of how the area G is illuminated.

According to an embodiment of the present application, in the scanning motion stage of the display module, any point on the display scanning path is filled with initial projection pixels and/or scanning projection pixels;

The scanning motion stage of the display module includes N sub-scanning stages, and the area defined by the display scanning path includes N display frames; N≥2 and N is an integer;

According to projection requirements, controlling the display status of the display module includes:

In the first sub-scanning stage, controlling the first type of display pixels corresponding to the first display frame to light up;

In the ith sub-scanning stage, the ith type display pixel corresponding to the ith display frame is controlled to light up; 1<i≤N and i is an integer;

In the Nth sub-scanning stage, the Nth type display pixels corresponding to the Nth display frame are controlled to light up.

When the radius of the circular scanning motion of the display module is larger, the more display scanning paths pass through the area G. In order to avoid display flickering, the area G can be lit in frames. For example, after the display module performs a circular motion to scan and rotate the preset angle, the area G is completely illuminated, and the preset angle can be divided into two, three or four angles, that is, the scanning movement stage of the display module is divided into two , three or four sub-scanning stages, the area G includes N display frames. The following takes three sub-scanning stages as an example for description.

It can be understood that the scanning stage of the display module is divided into three sub-scanning stages, and the imaging interval G is divided into three sub-scanning regions. In the first sub-scanning stage, the first type of display pixels corresponding to the first display frame are controlled. In the second sub-scanning stage, control the second-type display pixels corresponding to the second display frame to light up; in the third sub-scanning stage, control the third-type display pixels corresponding to the third display frame to light up.

For example, when the display module moves 120 degrees, the display scanning path of the display pixels can completely fill the pixel interval area G, and the positions of the scanning coverage points in the pixel interval area G will be distributed in 0-120 degrees, according to the movement angle of the display module. Differentiate the coverage points. Some points are covered at 0-40 degrees, some points are covered at 41-80 degrees, and some points are covered at 81-120 degrees. The number of times covered in each angle area may be once, two or three times, etc. When a point is covered only at 0-40 degrees, the lighting time of the point can only be covered when the display module circularly moves 0-40 degrees, and when a point is covered at other scanning angles other than 0-40 degrees ( Such as 41-80 degrees), at this time, you can choose an angle area to light up according to the amount of information of the two frames. When a point is covered by all three angle areas, one angle area can be randomly selected. In this way, all the points in the imaging interval area G can be divided into three frames according to the angle. In actual display, the information displayed in the three frames is a picture of one frame, thereby realizing frame-by-frame display and preventing flickering.

It should be noted that the display state of the display module can be controlled according to the rotation angle of the motor. The rotation angle of the motor corresponds to the scanning stage of the display module. When the motor rotates the first angle, the first type of display pixels corresponding to the first display frame of the control display module are turned on, and when the motor rotates at the second angle, the second type of display pixels corresponding to the second display frame of the display module are controlled to light up, When the motor rotates at a third angle, the third type of display pixels corresponding to the third display frame of the display module are controlled to light up. Among them, the rotation speed of the motor is 20 revolutions/S, and the display module rotates 120 degrees to display a complete picture, then it can display the picture display frame rate of 60 frames/S, and the complete display screen of 120 degrees is divided into 40 degrees. For one display frame, there can be a display frame rate of 180 frames/S.

According to an embodiment of the present application, any point on the display scan path corresponding to each display frame is lit once.

It can be understood that during the scanning motion of the display module, the imaging interval area G is divided into three sub-scanning areas. In the first sub-scanning stage, the first type of display pixels corresponding to the first display frame are controlled to light up; In the second sub-scanning stage, the second-type display pixels corresponding to the second display frame are controlled to light up; in the third sub-scanning stage, the third-type display pixels corresponding to the third display frame are controlled to light up. Wherein, when the first type of display pixel corresponding to the first display frame is turned on, and when the second type of display pixel corresponding to the second display frame is turned on, the two possible lighting positions may overlap. Taking the 11th curve, the 12th curve and the 13th curve in FIG. 11 as an example, in the first sub-scanning stage, the 11th curve first passes through the region G, then the 13th curve passes through the region G, and finally the 12th curve passes through the region G. When the 11th curve passes through the area G, the point a in the figure is illuminated, and when the thirteenth curve passes through the area G, the point a in the figure is also illuminated. When the curve 11 passes through the area G, the point b in the figure is lit, and when the curve 12 passes through the area G, the point b in the figure is also lit, and other points are also lit twice, not one by one here. enumerate. In this way, the brightness of point a, the brightness of point b, and the brightness of other repeated points are brighter than the brightness of other points in the region G, resulting in inconsistent display brightness.

Therefore, in order to ensure uniform brightness of the dots at each position in the area G, only the dots at each point position in the area G are controlled to be lit once. Still taking Fig. 11 as an example, the number of times that each other point in area G is lit is 1 time, therefore, point a and point b and other repeatedly lit points should also be lit only once. That is to say, when curve 11 passes through point a, it lights up, then curve 13 goes out when it passes point a, lights up when curve 11 passes through point b, then goes out when curve 12 passes through point b, and vice versa, when curve 11 passes through point a If it is off, then the curve 13 will light up when it passes through point a, the curve 11 will go out when it passes through point b, and then the curve 12 will light up when it passes through point b. In this way, the display brightness of each point in the area G is guaranteed to be uniform.

According to an embodiment of the present application, the display pixels include a first display pixel and a second display pixel, and each display pixel corresponds to a projection pixel on the projection screen;

During the projection process of the light projector, the display module performs a scanning motion, each display pixel corresponds to a display scanning path on the projection screen, each display scanning path corresponds to a plurality of scanning projection pixels, and the display scanning path covers the initial projection pixel and scanning Projected pixels, including:

During the projection process of the light projector, the display module performs a scanning motion to control the lighting time of the first display pixel and the second display pixel. The first display pixel corresponds to the first display scanning path on the projection screen, and the first display scanning path Overlaps the projection pixels of the plurality of second display pixels on the projection screen.

It should be noted that FIG. 13 is a projection image of a light projector in a method for controlling a light projector proposed by another embodiment of the present application. As shown in FIG. 13 , the display pixel includes a first display pixel and a plurality of second display pixels, wherein the first display pixel is the first display pixel, the plurality of second display pixels are the second to eighth display pixels, and the second display pixel is the second display pixel. The projected pixels from the eighth display pixel on the projection screen overlap with the first display scan path corresponding to the first display pixel on the projection screen, in other words, the projected pixels of the second to eighth display pixels on the projection screen Both are on the first display scanning path corresponding to the first display pixels on the projection screen.

That is to say, during the scanning motion of the display module, the display pixels corresponding to the other seven projection pixels on the display path of the first display pixel are simultaneously lit. Therefore, under the same brightness, the refresh frequency of the display module can be reduced, the projection resolution and brightness can be kept unchanged, and the power consumption of the display module can be reduced.

To sum up, according to the control method of the light projector proposed in the embodiment of the present application, the display state of the display pixels is controlled according to the projection requirements, and during the projection process of the light projector, each display pixel in the display module is projected during the projection process. The screen corresponds to a display scanning path, each display scanning path corresponds to a plurality of scanning projection pixels, and the display scanning path covers the initial projection pixels and the scanning projection pixels so that the projection image has high resolution and high brightness.

FIG. 14 is a block diagram of a projection device proposed by an embodiment of the present application. As shown in Figure 14, the projection device includes at least two projectors; the projection device further includes:

The image acquisition unit 113 is configured to acquire projection images of at least two projectors;

The control unit 114 is configured to adjust the outgoing image of each light projector according to the projected images of the at least two light projectors.

The following description will be given by taking two light projectors as an example, that is, the projection device includes a first light projector 111 , a second light projector 112 , an image acquisition unit 113 and a control unit 114 .

The first light projector 111 , the second light projector 112 and the image acquisition unit 113 are respectively connected to the control unit 114 , and the control unit 114 adjusts the first light projector 111 and the second light projector according to the images collected by the image acquisition unit 113 The outgoing image of the machine 112 .

According to an embodiment of the present application, the image acquisition unit 113 includes a camera or a camera.

The brightness and resolution of the projector are very important parameters. In this application, because it is a scanning imaging projection, the resolution can be very high. Because the brightness of the MicroLED chip is as high as 10 million nits, the brightness of the picture projected on the screen meets the needs of normal viewing. When it needs to be displayed in a brighter occasion, the application can superimpose multiple projectors to increase the projection brightness. Or when two or more chips are scanned and imaged overlapping, controlling the lighting state of the pixels of the display panel and the rotation state of the motor can realize the stepless doubling of the projection brightness or the projection area without losing the resolution, and realize the ultra-high brightness projection.

The following will introduce the superimposed display of multiple projectors to increase the projection brightness, and the superimposed display of multiple projectors to increase the projection area.

According to an embodiment of the present application, the projection images of the at least two light projectors completely overlap;

The control unit 114 is configured to adjust the synchronous projection display of the at least two light projectors according to the projected images of the at least two light projectors.

Taking two projectors as an example, the first projection image emitted by the first projector 111 completely overlaps with the second projection image emitted by the second projector 112, and the image acquisition unit 113 captures the first projection image and the second projection. image, when the first projection image and the second projection image do not completely overlap, the control unit 114 readjusts the first projection image and the second projection image emitted by the first projection light machine 111 according to the difference between the first projection image and the second projection image. Two second projection images output by the light projector 112 . It can be known that the second projection image emitted by the second projector 112 can only be adjusted based on the first projected image, or the first projected image emitted by the first projector 111 can be adjusted based on the second projected image. , it is also possible to adjust the first projection image emitted by the first projector 111 and the second projection image emitted by the second projector 112 at the same time based on the virtual reference, so that the first projection image and the second projection image are completely overlapped. , thereby increasing the brightness of the projected image.

When multiple projectors are superimposed and displayed, it is necessary to establish a signal synchronization control mechanism among the multiple projectors, so that the scanning motion state of the multiple projectors can maintain a fixed phase difference, so as to ensure that the frames of the multiple projectors can be synchronized. , so you need to set the correction time for each frame during display. For example, if the motor rotates 115 degrees to project a frame, the time for the motor to rotate 120 degrees will be set for one frame, and the extra time for the motor to rotate 5 degrees is reserved for the motor. Rotational state correction and/or display state correction of display pixels. In order to ensure the synchronous display quality of multiple projectors, the image acquisition unit 113 can be set to detect the projection quality and feedback the signal when multiple projectors are synchronously projected. When there is a deviation, a signal will be transmitted to the control unit 114 in time, and the control unit 114 will adjust the outgoing image of the projector according to the received signal. In the present application, scanning projection enables the projector to have super high resolution, which is the basis for superimposed display. Only super high display resolution can ensure that pixels of different projectors can be superimposed correspondingly during superposition. The image acquisition unit 113 can also provide a projection correction signal to the control unit 114 to non-linearly correct the projection image surface according to the display condition of the projection surface.

According to an embodiment of the present application, the projected image edges of at least two light projectors overlap;

The control unit 114 is configured to adjust the spliced projection display of the at least two light projectors according to the projected images of the at least two light projectors.

FIG. 15 is a projection image of a projection device proposed by an embodiment of the present application. As shown in Figure 15, the splicing of multiple projectors realizes the plan to increase the projection area. The projection display splicing and projection fusion technology are relatively mature, but most of these technologies are realized by the superposition of the projection area, which will lose the projection light to a certain extent. In this application, the splicing is realized without losing the resolution of the projector, and it is realized by superimposing the area where the edges are not completely scanned in the scanning scheme. Taking four projectors as an example, four projectors are used for projection. The projection area of the projector has a partially overlapping area, which is the splicing area 116 shown in the figure below, and this area 116 is the edge area of the projector. According to the aforementioned scanning and display principle, there may be incomplete scanning coverage at the edge of a single projector. When splicing, the incomplete coverage areas of adjacent projectors overlap each other to form an overlapping area, and the overlapping of scanning to form a splicing area can form a complete coverage, and finally realize the splicing display without wasting the edge area of the projector scanning. Thus, the projected display area is increased.

According to a specific embodiment of the present application, the data shown in Table 1 is the data of the projection lens of the projector, the equivalent focal length of which is 21mm-23.1mm, and the projection size at 2m is 53 inches. At this time, the display panel is far from the projector. The distance is about 21.2mm. A scanning lens is added in front of the projection lens. When the scanning lens is installed, its optical axis is at a certain distance from the optical axis of the projection lens, that is, the polarized axis of the scanning lens is installed. Taking the lens focal length of 30mm as an example, it is calculated according to the formula for calculating the equivalent focal length of the lens combination.

Where f1 is the equivalent focal length of the projection lens, f2 is the focal length of the scanning lens mounted on the polarizing axis, and s is the distance between them.

When f1=21mm, f2=30mm, s=10mm, f combination=15.36mm can be calculated, according to the calculation formula of the viewing angle of the projector

where k is the diagonal of the display panel, f is the focal length of the projection lens, and FOV is the display angle of view. When k is constant, FOV is negatively correlated with f. In this application, the combination of f < f1, that is, the angle of view of the combined lens will be larger than the original The lens angle of view, that is, the projection angle of view of the original projection lens is expanded, and the projection area at 2m will be larger than the original 53 inches. In this application, the distance between the projection lens and the scanning projection is 10 mm, so when selecting the projection lens, it is necessary to select appropriate parameters so that a lens can be added between the display panel and the projection lens.

Table 1 Data of the projection lens of the projector

FIG. 16 is an optical path diagram of a projection device proposed by a specific embodiment of the present application. FIG. 16 is an example of using the above-mentioned projection lens 102, and the scanning lens 1012 is located between the display panel 1011 and the projection lens 102. It can be seen from FIG. 16 that the angle of view when the scanning lens 1012 and the projection lens 102 are installed coaxially is more than off-axis. The viewing angle of the installation is small and the display pixel projection position changes.

To sum up, according to the projection device proposed in the embodiments of the present application, the projection images of at least two light projectors are collected by the image acquisition unit, and the control unit adjusts the output of each light projector according to the projection images of the at least two light projectors image, so that the image projected by the projection device has high resolution and high brightness.

Claims

A light projector includes a display module and a projection lens, the projection lens is disposed on the light-emitting side of the display module, and the central axis of the display module is parallel to and does not overlap with the optical axis of the projection lens;

The display module includes a plurality of display pixels, and each of the display pixels corresponds to an initial projection pixel on the projection screen. During the projection process of the light projector, the display module is configured to perform a scanning motion, and each of the display pixels corresponds to an initial projection pixel on the projection screen. The display pixels correspond to a display scan path on the projection screen, each of the display scan paths corresponds to a plurality of scan projection pixels, and the display scan paths cover the initial projection pixels and the scan projection pixels; and The plurality of display pixels include a first display pixel and a second display pixel. During the scanning motion of the display module, the direction of the first display pixel pointing to the second display pixel does not change.
The light projector according to claim 1, wherein the display module comprises a display panel; the central axis of the display panel is parallel to the optical axis of the projection lens and does not overlap;

During projection by the light projector, the display panel is configured to move.
The projector according to claim 1, wherein the display module comprises a display panel and a scanning lens; the optical axis of the scanning lens is parallel to and does not overlap with the optical axis of the projection lens;

During the projection process of the light projector, the display panel is fixed, and the scanning lens is configured to perform a scanning motion.
The light projector according to claim 3, wherein the scanning lens is arranged in an optical path between the display panel and the projection lens;

Alternatively, the projection lens includes a plurality of projection lenses, and the scanning lens is disposed in the optical path between any two adjacent projection lenses.
The projector according to claim 3, wherein the scanning lens comprises a plurality of sub-scanning lenses, and a plurality of the sub-scanning lenses are arranged in an array.
The optical projector according to claim 2 or 3, wherein the display panel comprises a micro light emitting diode display panel, a vertical cavity surface emitting laser display panel, or a quantum dot display panel.
The light projector according to claim 1, wherein the scanning motion of the display module comprises at least one of linear scanning motion, circular scanning motion, elliptical scanning motion, figure 8 scanning motion and Lissajous figure scanning motion .
A control method of a light projector, applied to the light projector described in any one of claims 1-7, comprising:

controlling the display state of the display pixels according to the projection requirements; wherein, the display state includes the lighting time and display brightness of the display pixels;

During the projection process of the light projector, the display module is controlled to perform a scanning motion.
The control method of the light projector according to claim 8, wherein,

According to projection requirements, the steps of controlling the display state of the display module include:

In the first sub-scanning stage, controlling the first type of display pixels corresponding to the first display frame to light up;

In the Nth sub-scanning stage, the Nth type display pixels corresponding to the Nth display frame are controlled to light up, where N≧2 and N is an integer.
The control method for a light projector according to claim 9, further comprising: lighting any point on the display scanning path corresponding to each display frame once.
The control method of the light projector according to claim 8, wherein, during the projection process of the light projector, the step of controlling the display module to perform a scanning motion comprises: during the projection process of the light projector , control the display module to perform a scanning motion, and control the lighting time of the first display pixel and the second display pixel, so that the first display scanning path and a plurality of the second display pixels are on the projection screen The projection pixels overlap, wherein the first display pixel corresponds to the first display scan path on the projection screen.
A projection device, comprising at least two light projectors according to any one of claims 1-7, the projection device further comprising:

an image acquisition unit configured to acquire projection images of at least two of the light projectors;

The control unit is configured to adjust the outgoing image of each of the light projectors according to the projected images of at least two of the light projectors.
The projection apparatus of claim 12, wherein the projection images of at least two of the light projectors completely overlap;

The control unit is configured to adjust the synchronous projection display of at least two of the light projectors according to the projected images of the at least two light projectors.
The projection apparatus of claim 12, wherein the projected image edges of at least two of the light projectors overlap;

The control unit is configured to adjust the spliced projection display of the at least two light projectors according to the projection images of the at least two light projectors.
The projection apparatus of claim 12, wherein the image acquisition unit comprises a camera or a camera.