Laser, laser light source, and laser projection device

Abstract

The application discloses a laser, a laser light source and a laser projection device, and belongs to the projection display field.The laser comprises a substrate and a plurality of laser units arranged in an array on the substrate.In the application, the laser comprises two rows of laser units, one row of red light laser units for emitting red laser, and the other row of green light laser units for emitting green laser and blue light laser units for emitting blue laser.Under the premise of ensuring the brightness of the laser beam emitted by the laser, the number of laser units in the laser is reduced.Thus, the overall volume of the laser can be effectively reduced, and the volume of the laser projection device integrated with the laser is small.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of projection display, in particular to a laser, a laser light source and a laser projection device. BACKGROUND

[0002] With the development of optoelectronic technology, the requirements for the projection picture of the laser projection device are getting higher and higher. At present, in order to ensure the display brightness of the projection picture, a laser is usually used to provide illumination for the laser projection device. The laser beam emitted by the laser has the advantages of good monochromaticity and high brightness, and is a relatively ideal light source.

[0003] At present, the light emitted by the laser projection device is usually provided by a laser. As shown in Figure 1 and Figure 2 , a structure diagram of a laser provided in the related art is shown in Figure 1 , and a distribution diagram of a laser unit in the laser shown in Figure 2 is shown in Figure 1 . The laser includes a row of light emitting chips for emitting blue laser, a row of light emitting chips for emitting green laser and two rows of light emitting chips for emitting red laser. In the example, the number of light emitting chips for emitting laser of different colors in each row is seven.

[0004] However, the number of laser chips in the current laser is relatively large, which leads to a large overall volume of the laser, and further leads to a large volume of the laser projection device. SUMMARY

[0005] Embodiments of the present application provide a laser, a laser light source and a laser projection device. The problem of large overall volume of the laser in the prior art can be solved, and the technical solution is as follows:

[0006] On the one hand, a laser is provided, and the laser includes:

[0007] a substrate, and a plurality of arrayed laser units on the substrate;

[0008] wherein the plurality of laser units are arranged in two rows, each laser unit in one row of laser units is a red laser unit for emitting red laser; a part of laser units in the other row of laser units are green laser units for emitting green laser, and the other part of laser units are blue laser units for emitting blue laser, and the two laser units located at the end in the other row of laser units are the blue laser units.

[0009] On the other hand, a laser light source is provided, and the laser light source includes: a laser, a light combining mirror group, a shaping mirror group, a lens assembly and a light pipe. The laser is the laser given in the above.

[0010] The light combiner is located at the light emitting side of the laser, and the arrangement direction of the laser and the light combiner is perpendicular to the arrangement direction of the light combiner, the shaping mirror group, the lens assembly and the light guide pipe.

[0011] The laser is configured to emit three colors of laser light to the light combiner.

[0012] The light combiner is configured to guide the three colors of laser light to the shaping mirror group after the three colors of laser light are combined.

[0013] The shaping mirror group is configured to shape the combined laser light beam, so that the width of the light spot of the shaped laser light beam in the slow axis direction of the laser is less than the width of the light spot of the unshaped laser light beam in the slow axis direction.

[0014] The shaping mirror group is further configured to guide the shaped laser light beam to the lens assembly, and the lens assembly is configured to adjust the laser light beam and guide the adjusted laser light beam to the light guide pipe.

[0015] In another aspect, a laser projection device is provided, which includes a laser light source, a light valve and a projection lens. The laser light source is the laser light source given in the above.

[0016] The technical solutions provided by the embodiments of the present application have at least the following beneficial effects:

[0017] A laser includes a substrate and a plurality of laser units arranged in an array on the substrate. In the present application, the laser includes two rows of laser units, one row of red laser units for emitting red laser light, and another row of green laser units for emitting green laser light and blue laser units for emitting blue laser light. Under the premise of ensuring the brightness of the laser light beam emitted by the laser, the number of laser units in the laser is reduced. In this way, the overall volume of the laser can be effectively reduced, thereby making the volume of the laser projection device integrated with the laser smaller. In addition, when the end of the laser unit containing the blue laser unit and the green laser unit is a blue laser unit, the perception effect of the human eye for the combined laser light of the three colors can be effectively balanced, and the display effect of the laser projection device integrated with the laser is effectively improved. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0019] Figure 1 is a structural schematic diagram of a laser provided by the related art;

[0020] Figure 2 is Figure 1 is a distribution schematic diagram of a laser unit in the laser shown in

[0021] Figure 3 is a structural schematic diagram of a laser provided by an embodiment of the present application;

[0022] Figure 4 is Figure 3 is a distribution schematic diagram of a laser unit in the laser shown in

[0023] Figure 5 is a distribution schematic diagram of another laser unit provided by an embodiment of the present application;

[0024] Figure 6 is a structural schematic diagram of another laser provided by an embodiment of the present application;

[0025] Figure 7 is a partial structural schematic diagram of a laser light source provided by an embodiment of the present application;

[0026] Figure 8 is an effect diagram of shaping of a laser beam by a shaping lens group provided by an embodiment of the present application;

[0027] Figure 9 is Figure 7 is a top view of the laser light source shown in

[0028] Figure 10 is a structural schematic diagram of another laser light source provided by an embodiment of the present application;

[0029] Figure 11 is a structural schematic diagram of still another laser light source provided by an embodiment of the present application;

[0030] Figure 12 is a partial structural schematic diagram of still another laser light source provided by an embodiment of the present application;

[0031] Figure 13 is a structural schematic diagram of a laser projection device provided by an embodiment of the present application.

[0032] The above-described drawings have shown the explicit embodiments of the present application, and the following will have a more detailed description. These drawings and the written description are not intended to limit the scope of the concept of the present application by any means, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0033] For the purpose, technical solutions and advantages of the present application to be clearer, the embodiments of the present application will be described in further detail below with reference to the drawings.

[0034] Please refer to Figure 3 and Figure 4 , Figure 3 is a structural schematic diagram of a laser provided by an embodiment of the present application, Figure 4 is Figure 3 a distribution schematic diagram of laser units in the laser shown in FIG. 1. The laser 000 can include a substrate 100 and a plurality of laser units 200 arranged in an array on the substrate. The plurality of laser units 200 can be integrated in the laser 000 in an array arrangement, and the plurality of laser units 200 can be arranged in two rows in the laser 000. In the two rows of laser units 200, each laser unit 200 in one row of laser units 200 can be a red laser unit for emitting red laser light; some laser units 200 in the other row of laser units 200 can be green laser units for emitting green laser light, and the other laser units 200 can be blue laser units for emitting blue laser light. Moreover, the two laser units 200 at the ends in the row of laser units for emitting green laser light and blue laser light are both blue laser units for emitting blue laser light.

[0035] In the present application, the light emitting power range of the red laser unit can be 24W-56W, the light emitting power range of the blue laser unit can be 48W-115W, and the light emitting power range of the green laser unit can be 12W-28W. For example, the light emitting power of the red laser unit is 48W, the light emitting power of the blue laser unit is 82W, and the light emitting power of the green laser unit is 24W.

[0036] In the embodiment of the present application, when the laser 000 includes one row of red laser units for emitting red laser light, one row of green laser units for emitting green laser light, and blue laser units for emitting blue laser light, the number of laser units 200 in the laser 000 can be reduced while ensuring the brightness of the laser beam emitted by the laser 000. In this way, the overall volume of the laser 000 can be effectively reduced, and thus the volume of the laser projection device integrated with the laser 000 is relatively small.

[0037] In addition, in the subsequent light collection process using the light pipe, the light collection of the light pipe has a certain angle, resulting in a large loss of laser at the end of each row of the laser 000 when guiding the light pipe. Since the human eye has a smaller perception function for blue laser than for green laser, when the end of the laser unit 200 containing the blue laser unit and the green laser unit is a blue laser unit, the perception effect of the human eye after combining the three colors of laser light can be effectively balanced, and the display effect of the laser projection device integrated with the laser 000 can be effectively improved. In this application, the laser 000 used to emit three-color laser light can use an MCL-type laser.

[0038] In summary, the laser provided by the embodiments of the present application includes a substrate and a plurality of laser units arranged in an array on the substrate. In this application, the laser includes two rows of laser units, one row of red laser units for emitting red laser light, and another row of green laser units for emitting green laser light and blue laser units for emitting blue laser light. Under the premise of ensuring the brightness of the laser beam emitted by the laser, the number of laser units in the laser is reduced. In this way, the overall volume of the laser can be effectively reduced, thereby making the volume of the laser projection device integrated with the laser smaller. In addition, when the end of the laser unit containing the blue laser unit and the green laser unit is a blue laser unit, the perception effect of the human eye after combining the three colors of laser light can be effectively balanced, and the display effect of the laser projection device integrated with the laser can be effectively improved.

[0039] In the embodiments of the present application, please refer to Figure 5 , Figure 5 is another distribution diagram of a laser unit provided by the embodiments of the present application. The distance d between the two adjacent laser units 200 in each row of laser units 200 in the laser 000 can be 1.3 mm to 3 mm. For example, the distance between the two adjacent laser units 200 in each row of laser units 200 can be 1.5 mm. In this way, the distance between the two adjacent laser units 200 in each row of laser units 200 is small, that is, the overall volume of the laser 000 can be further effectively reduced.

[0040] Optionally, in the row of laser units 200 for emitting green laser light and blue laser light, at least one blue laser unit 200a can be arranged between the two blue laser units 200a at the end. And the at least one blue laser unit 200a can be arranged between the two green laser units 200b for emitting green laser light. In this way, the blue laser units 200a and the green laser units 200b are arranged alternately, which can effectively improve the uniformity of the light beam after the subsequent combination of the blue laser, the green laser and the red laser through the light combiner.

[0041] It should be noted that the speckle effect is usually generated when the laser is used as the light source of the projection device for projection display in the related art. The speckle effect refers to that two beams of laser emitted by the coherent light source are scattered after irradiating a rough object (such as the screen of the projection device), and then the two beams of laser generate interference in space, and finally the granular bright and dark spots appear on the screen. Two adjacent light emitting chips in the laser that emit the laser with the same wavelength and constant phase are the coherent light source. The speckle effect makes the display effect of the projection image poor, and the un-focused bright and dark spots in the flickering state are seen by the human eye, and dizziness is easily generated after long time watching, and the user experience is poor.

[0042] In the embodiment of the present application, in the red light laser unit 200c in which all the red light laser units in a row emit red laser, the central wavelength of the red laser emitted by the red light laser unit 200c can increase in turn along the direction from both sides to the middle. In this way, for the two adjacent light emitting chips whose central wavelengths of the emitted laser are in the same wavelength range, the central wavelengths of the laser emitted by the two light emitting chips are different, so the two light emitting chips are not coherent light sources. Therefore, the laser emitted by the two light emitting chips is difficult to generate interference, and thus the speckle effect when the laser is used as the light source of the projection device for projection display can be reduced, the projection image is prevented from being distorted, the display effect of the projection image is improved, and the dizziness generated by the human eye when watching is avoided. In addition, the red light laser unit 200c that emits red laser with a shorter central wavelength is sensitive to temperature changes and has a large amount of heat. The red light laser unit 200c that emits red laser with a shorter central wavelength is arranged at the end of the row of laser units. Therefore, the heat emitted by the laser unit can be effectively dissipated to the external environment, and the influence on other laser units is avoided as much as possible.

[0043] Optionally, the red light laser unit 200c in which all the red light laser units in a row emit red laser can include at least one first red light laser unit c1 located in the central region of the row of red light laser units 200c, and at least two second red light laser units c2 located on both sides of the at least one first red light laser unit c1. The central wavelength of each first red light laser unit c1 located in the central region can be the same. In the at least two second red light laser units c2 located on both sides of the at least one first red light laser unit c1, the central wavelengths of the two second red light laser units c2 with the same distance from the central region can be the same. For example, the red light laser unit 200c in which all the red light laser units in a row emit red laser can include four second red light laser units c2, i.e., the second red light laser unit c21 and the second red light laser unit c22. For example, the central wavelength of the first red light laser unit c1 can be 647 nanometers, the central wavelength of the second red light laser unit c21 is 643 nanometers, and the central wavelength of the second red light laser unit c22 is 639 nanometers.

[0044] In the embodiments of the present application, refer to Figure 6 , Figure 6 is another structure diagram of a laser provided by the embodiments of the present application. The laser 000 can also include three first conductive pins 300 and one second conductive pin 400 on the substrate 100. The three first conductive pins 300 on the substrate 100 can be connected with the first end of the plurality of red light laser units 200c in series, the first end of the plurality of green light laser units 200b in series and the first end of the plurality of blue light laser units 200a in series respectively. The second conductive pin 400 can be connected with the second end of the plurality of red light laser units 200c in series, the second end of the plurality of green light laser units 200b in series and the second end of the plurality of blue light laser units 200a in series simultaneously. Among them, one of the first conductive pin 300 and the second conductive pin 400 can be a positive pin, and the other can be a negative pin. In the present application, when the first conductive pin 300 is a positive pin and the second conductive pin 400 is a negative pin, the three first conductive pins 300 are connected with the first end of the plurality of red light laser units 200c in series, the first end of the plurality of green light laser units 200b in series and the first end of the plurality of blue light laser units 200a in series respectively. The second conductive pin 400 is connected with the second end of the plurality of red light laser units 200c in series, the second end of the plurality of green light laser units 200b in series and the second end of the plurality of blue light laser units 200a in series simultaneously. That is, the plurality of red light laser units 200c in series, the plurality of green light laser units 200b in series and the plurality of blue light laser units 200a in series share one negative pin, for example, (R, G, B)-, R+, G+, B+. When the first conductive pin 300 is a negative pin and the second conductive pin 400 is a positive pin, the three first conductive pins 300 are connected with the first end of the plurality of red light laser units 200c in series, the first end of the plurality of green light laser units 200b in series and the first end of the plurality of blue light laser units 200a in series respectively. The second conductive pin 400 is connected with the second end of the plurality of red light laser units 200c in series, the second end of the plurality of green light laser units 200b in series and the second end of the plurality of blue light laser units 200a in series simultaneously. That is, the plurality of red light laser units 200c in series, the plurality of green light laser units 200b in series and the plurality of blue light laser units 200a in series share one positive pin, for example, (R, G, B)+, R-, G-, B-, which is not limited by the embodiments of the present application. In this way, the laser 000 shares the positive pin or the negative pin, thereby reducing the manufacturing cost of the laser 000 and simplifying the packaging process of the laser 000.

[0045] The red laser unit 200c, the green laser unit 200b and the blue laser unit 200a are connected with one end of the first conductive pin 300 and the second conductive pin 400, which are used for transmitting signals for emitting different color laser units 200 to emit light, and the other end of the first conductive pin 300 and the second conductive pin 400 extends to the outside of the substrate 100. Among them, the first conductive pin 300 and the second conductive pin 400 are also used to connect with the circuit board (not shown in the figure) in the laser projection device, so as to turn on the laser unit 200 and the circuit board, so that the light emitting chip of the laser unit 200 emits light.

[0046] Optionally, each of the plurality of laser units 200 can include one light emitting chip, that is, the laser 000 can include a plurality of light emitting chips arranged in an array. Each row of light emitting chips in the plurality of light emitting chips is used to emit laser of different colors. In this application, the laser 000 includes light emitting chips arranged in two rows and seven columns, wherein one row of light emitting chips is used to emit red laser, and one row of light emitting chips is used to emit green laser and blue laser. For example, the number of red laser units 200c can be seven, the number of green laser units 200b can be four, and the number of blue laser units 200a can be three. In other possible implementations, the plurality of light emitting chips can also be arranged in other arrangements, which are not limited in the embodiments of the present application.

[0047] In summary, the laser provided by the embodiments of the present application includes: a substrate, and a plurality of laser units arranged in an array on the substrate. In this application, the laser includes two rows of laser units, one row of red laser units for emitting red laser, and another row of green laser units for emitting green laser and blue laser units for emitting blue laser. On the premise of ensuring the brightness of the laser beam emitted by the laser, the number of laser units in the laser is reduced. In this way, the overall volume of the laser can be effectively reduced, and the volume of the laser projection device integrated with the laser is also small. In addition, when the end of the laser unit containing the blue laser unit and the green laser unit is the blue laser unit, the perception effect of the human eye to the combined light of the three colors of laser can be effectively balanced, and the display effect of the laser projection device integrated with the laser is effectively improved.

[0048] Generally, the multiple laser units of the laser in the laser light source emit laser beams to the light combiner, and the shape of the light spot formed after the laser beams reflected by the light combiner and combined is generally rectangular, and the width of the light spot in the slow axis direction of the laser (i.e., the size of the long side of the light spot) is greater than the width in the fast axis direction of the laser (i.e., the size of the short side of the light spot). For example, the ratio between the size of the long side of the light spot formed after the laser beams are combined and the size of the short side is 3:1.

[0049] According to the calculation formula of the optical etendue in the optical principle, the calculation formula of the etendue of the illumination of the laser projection device is:

[0050] π×S×(SinQ) 2 ;

[0051] wherein S is the area of the light receiving surface of the light valve in the laser projection device, here, the light receiving surface of the light valve is generally rectangular, and therefore, the area S of the light receiving surface of the light valve can be represented by the product of the width H1 of the long side and the width H2 of the short side of the light receiving surface; Q is the exit angle of the laser beam after passing through the projection lens in the laser projection device, and after the type of the projection lens is determined, the value of the F# of the projection lens is determined, and therefore, the exit angle Q of the laser beam after passing through the projection lens can be determined according to the F# of the projection lens, wherein the relationship between F# and Q is as follows: Q=1 / 2F#.

[0052] That is, the calculation formula of the etendue of the illumination of the laser projection device is:

[0053] π×H1×H2×Sin 2 (1 / 2F#);

[0054] According to the above formula, after the type of the light valve and the type of the projection lens are determined, the etendue of the illumination of the laser projection device is determined, and the corresponding Lagrangian invariant of the long side and the short side is determined. However, since the size of the long side of the light spot formed after the laser beams emitted by the laser and combined by the light combiner is greater than the size of the short side, the exit angle of the laser beam in the long side direction of the light spot to the light guide pipe is greater than the exit angle in the short side direction of the light spot. In this way, the Lagrangian invariant of at least one of the long side and the short side of the light spot does not meet the requirements.

[0055] For example, the formula of the Lagrangian invariant is as follows:

[0056] n×SinQ×Y=n'×SinQ'×Y';

[0057] Wherein, n and n' are the refractive index of the transmission medium, in the laser projection device, n and n' can be the refractive index of air, therefore, n = n'; Q is the exit angle of the laser beam through the projection lens in the laser projection device; Y is the image height of the imaging object; Q' is the incident angle of the laser beam to the projection lens, since the laser beam in the laser light source is emitted from the light pipe and then reflected multiple times to the projection lens, therefore, Q' can be represented by the exit angle of the light pipe; Y' is the object height of the imaging object.

[0058] Since the aspect ratio of the imaging picture after the laser beam passes through the projection lens is the same as the aspect ratio of the light-receiving surface of the light valve. Therefore, according to the formula of the Lagrange invariant, the expression of the long side of the light spot after exiting through the projection lens can be: n x Sin(1 / 2F#) x H1, and the expression of the short side of the light spot after exiting through the projection lens can be: n x Sin(1 / 2F#) x H2. And the expression of the long side of the light spot when it is incident to the projection lens can be: n' x Sin(Q1') x d1, and the expression of the short side of the light spot when it is incident to the projection lens can be: n' x Sin(Q2') x d2. Wherein, d1 is the size of the long side of the light spot formed after the laser beams are combined, d2 is the size of the short side of the light spot formed after the laser beams are combined; Q1' is the exit angle of the laser beam incident to the light pipe 03 in the long side direction of the light spot, Q2' is the exit angle of the laser beam incident to the light pipe in the short side direction of the light spot.

[0059] In order to ensure that the laser projection device has high light output efficiency, it is usually necessary to make the long side of the light spot satisfy the Lagrange invariant. That is, it is necessary to ensure that k x Sin(1 / 2F#) x H1 = Sin(Q1') x d1. Wherein, k is a constant.

[0060] Q1' and Q2' in the above expression satisfy the following relationship:

[0061]

[0062] Wherein, D1 is the width of the long side of the light pipe, D2 is the width of the short side of the light pipe, and F is the focal length of the light pipe. In the laser light source, the light valve needs to correspond to the light pipe. That is, the aspect ratio of the light pipe needs to be approximately the same as the aspect ratio of the light-receiving surface of the light valve. Thus, according to the above relationship, it can be concluded that the ratio between Q1' and Q2' is approximately equal to H1: H2.

[0063] As can be seen from the above, since the size of the long side of the spot formed after the laser beams are combined is greater than the size of the short side, when k x Sin(1 / 2F#) x H1 = Sin(Q1') x d1, k x Sin(1 / 2F#) x H2 > Sin(Q2') x d2. In this way, the expansion amount of the laser beams in the short side direction of the spot is relatively large, and the transmission efficiency of the light valve in the laser light source to the laser beams emitted by the laser is relatively low.

[0064] Please refer to Figure 7 , Figure 7 is a partial structure diagram of a laser light source provided by an embodiment of the present application. The laser light source 00 can include a laser 000, a light-combining lens group 001, a shaping lens group 002, a lens assembly 003, and a light guide pipe 004. The laser 000 can be a blue laser, a green laser, and a red laser. Figure 3 、 Figure 5 or Figure 6 laser light source.

[0065] The light-combining lens group 001 can be located on the light-emitting side of the laser 000, and the arrangement direction (such as the Y-axis direction in Figure 7 ) of the laser 000 and the light-combining lens group 001 is perpendicular to the arrangement direction (such as the X-axis direction in Figure 7 ) of the light-combining lens group 001, the shaping lens group 002, the lens assembly 003, and the light guide pipe 004.

[0066] Among them, the laser 000 in the laser light source 00 can be used to emit three colors of laser light to the light-combining lens group 001. For example, the three colors of laser light can include blue laser light, green laser light, and red laser light. It should be noted that the embodiments in the present application are all illustratively described taking the laser 000 emitting three colors of laser light including blue laser light, green laser light, and red laser light at the same time as an example.

[0067] In the present application, after the laser beam emitted by the laser 000 is incident on the light-combining lens group 001, the light-combining lens group 001 reflects the laser beam to the shaping lens group 002. After the shaping lens group 002 shapes the laser beam, the laser beam is guided to the lens assembly 003. The lens assembly 003 is used to adjust the received laser beam, and the adjusted laser beam is guided to the light guide pipe 004. In this way, the laser light source 000 can shape the laser beam combined by the light-combining lens group 001 through the shaping lens group 002, so that the width of the shaped laser beam spot in the slow axis direction of the laser is small, and the difference between the width of the shaped laser beam spot in the slow axis direction of the laser and the width of the shaped laser beam spot in the fast axis direction of the laser (i.e., the size of the short side of the spot) is small. In this way, the expansion loss of the laser beam in the short side direction of the spot can be effectively reduced, and the transmission efficiency of the light valve in the laser light source to the laser beam emitted by the laser 000 is improved.

[0068] In the embodiment of the present application, the width of the laser beam spot in the slow axis direction of the laser after the shaping lens group 002 shapes the laser beam can be equal to the width of the laser beam spot in the fast axis direction of the laser after the shaping lens group 002 shapes the laser beam. That is, the ratio between the width of the laser beam spot in the slow axis direction of the laser after the shaping lens group 002 shapes the laser beam and the width of the laser beam spot in the fast axis direction of the laser after the shaping lens group 002 shapes the laser beam can be 1. For example, when k x Sin(1 / 2F#) x H1 = Sin(Q1') x d1, since the value of d1:d2 is 1, k x Sin(1 / 2F#) x H2 = Sin(Q2') x d2 can be satisfied. In this way, the expansion loss of the laser beam in the short side direction of the spot can be further effectively reduced, and the transmission efficiency of the light valve in the laser light source to the laser beam emitted by the laser is further improved.

[0069] The light guide pipe 004 in the present application is a rectangular tubular device spliced by four plane reflecting sheets, that is, a hollow light guide pipe. Light is reflected multiple times inside the light guide pipe 004 to achieve the effect of uniform light. The light guide pipe can also be a solid light guide pipe. The light inlet and the light outlet of the light guide pipe 004 are rectangular with consistent shape and area. The light beam enters the light inlet of the light guide pipe 004 and is emitted from the light outlet of the light guide pipe 004 to the light valve assembly. The light beam homogenization and spot optimization are completed during the process in the light guide pipe 004.

[0070] Beam homogenization refers to transforming an inhomogeneous intensity distribution of a light beam into a uniform cross-sectional distribution of the light beam. Speckle refers to the random granular intensity pattern that occurs when laser light sources are used to illuminate a rough surface such as a screen or any other object that produces diffuse reflection or diffused transmission of light, and the light beams interfere to form bright or dark spots.

[0071] Optionally, please refer to Figure 9 , Figure 9 is Figure 7 a top view of a laser light source. The shaping mirror group 002 in the laser light source 00 can have a first cylindrical surface A and a second cylindrical surface B. The first cylindrical surface A can be closer to the light combining mirror group 001 relative to the second cylindrical surface B.

[0072] The shaping mirror group 002 can be configured to converge the combined laser beams in the slow axis direction of the laser light through the first cylindrical surface A, and the shaping mirror group 002 can also be configured to collimate the converged laser beams through the second cylindrical surface B to obtain the laser beams reshaped by the shaping mirror group 300.

[0073] In the embodiments of the present application, please refer to Figure 9 and Figure 10 , Figure 10 is a structural diagram of another laser light source provided by the embodiments of the present application. The shaping mirror group 002 in the laser light source 00 can include two cylindrical lenses. For example, the two cylindrical lenses can be a first cylindrical lens 0021 and a second cylindrical lens 0022. Among them, the first cylindrical lens 0021 is the cylindrical lens closer to the light combining mirror group 001 among the two cylindrical lenses, and the second cylindrical lens 0022 is the cylindrical lens closer to the light guide pipe 004 among the two cylindrical lenses.

[0074] The arrangement direction of the first cylindrical lens 0021 and the second cylindrical lens 0022 (such as the X-axis direction in Figure 7 ) can be perpendicular to the arrangement direction of the laser 000 and the light combining mirror group 001 (such as the Y-axis direction in Figure 7 ), and the first cylindrical lens 0021 closer to the light combining mirror group 001 among the two cylindrical lenses in the shaping mirror group 002 can have a first cylindrical surface A, and the second cylindrical lens 0022 closer to the light guide pipe among the two cylindrical lenses can have a second cylindrical surface B.

[0075] Among them, please refer to Figure 9 and Figure 10The light-incident surface of the first cylindrical lens 0021, i.e., the first cylindrical arc surface A, can be a cylindrical convex surface, and the light-exit surface of the first cylindrical lens 0021 can be a plane; the light-incident surface of the second cylindrical lens 0022, i.e., the second cylindrical arc surface B, can be a cylindrical concave surface, and the light-exit surface of the second cylindrical lens 0022 can be a plane. Thus, when the laser beam passes through the first cylindrical lens 0021, the first cylindrical lens 0021 can converge the laser beam in the slow axis direction, ensuring that the width of the combined laser beam spot in the slow axis direction is shaped to be the same as the width of the combined laser beam spot in the fast axis direction. The second cylindrical lens 0022 can collimate the laser beam emitted from the first cylindrical lens 0021 and guide it to the light guide 004.

[0076] The laser source 00 may also include: a plane mirror 005, which may be located between two cylindrical lenses. The plane mirror 005 may be used to adjust the direction of the laser beam emitted from the cylindrical lens that is closer to the beam combiner 001 to the cylindrical lens that is closer to the light guide 004.

[0077] It should be noted that when the space inside the projection device is small, such as along the central axis of the combining lens group 001 ( Figure 10 When the X-axis direction of the lens assembly cannot simultaneously accommodate the shaping mirror group 002 and the lens assembly 003, the positions of the shaping mirror group 002 and the lens assembly 003 can be adjusted. Then, under the action of the plane mirror 005, the direction of the laser beam emitted from the cylindrical lens in the shaping mirror group 002 near the beam combining mirror group 001 is adjusted to face the cylindrical lens in the shaping mirror group 002 near the light guide 004. After the laser beam is shaped by the cylindrical lens, it is guided to the lens assembly 003.

[0078] In this embodiment of the application, the light combining mirror assembly 001 may include: along Figure 10 A first lens 0011 and a second lens 0012 are arranged sequentially along the X-axis. On a plane parallel to the light-emitting surface of the first cylindrical lens 0021, the orthographic projections of the first lens 0011 and the second lens 0012 at least partially overlap. Thus, a laser 000 emits a laser beam towards the first lens 0011 and the second lens 0012. This laser beam may include three colors of laser light (e.g., blue, green, and red). For example, the laser 000 may emit blue and green laser light towards the first lens 0011, and the first lens 0011 may reflect the blue and green laser light towards the orthopedic lens assembly 002; the laser 000 may also emit red laser light towards the second lens 0012, and the second lens 0012 may reflect the red laser light towards the orthopedic lens assembly 002.

[0079] For example, the first lens 0011 in the light combination lens set 001 can be a mirror for reflecting all colors of laser light, or can be a dichroic plate for reflecting green laser light and blue laser light and transmitting other colors of laser light; the second lens 0012 in the light combination lens set 001 can be a dichroic plate for reflecting red laser light and transmitting other colors of laser light.

[0080] Optionally, please refer to Figure 11 , Figure 11 is another structure diagram of a laser light source provided by an embodiment of the present application. The laser light source 00 can further include a diffusion plate 006. The diffusion plate 006 can be located between the shaping assembly 002 and the lens assembly 003. The laser light beam emitted from the shaping assembly 300 can be emitted to the diffusion plate 006 along the X-axis direction in the middle, and the diffusion plate 006 can homogenize the incident laser light beam and then emit it to the lens assembly 003. Figure 10

[0081] Since the light source is a pure three-color laser light source, speckle is a unique phenomenon of laser light. In order to obtain a higher display quality of the projected image, further speckle elimination processing is required for the three-color laser light. In the present application, a diffusion wheel 007, i.e., a rotating diffusion plate, is further arranged between the lens assembly 003 and the light guide pipe 004. The diffusion wheel can diffuse the converging light beam, increase the divergence angle of the light beam, and increase the random phase. In this way, since the homogenizing diffusion plate 006 is arranged in the front light path, the laser light beam is homogenized after passing through the homogenizing diffusion plate 006, is converged by the lens assembly 003, and is incident to the diffusion wheel 007. The laser light beam first passes through a static diffusion plate 006 and then passes through a moving diffusion plate 007. In this way, on the basis of the homogenization of the light beam by the static diffusion plate 006, the laser light beam is again diffused and homogenized, which can enhance the homogenization effect of the laser light beam, reduce the energy proportion of the light beam near the optical axis of the laser light beam, and thus reduce the coherence degree of the laser light beam. The speckle phenomenon of the projected image can be greatly improved.

[0082] In the embodiment of the present application, the polarization polarity of the blue laser light and the green laser light emitted by the laser 000 is opposite to the polarization polarity of the red laser light. For example, the blue laser light and the green laser light are S-polarized light, and the red laser light is P-polarized light. For this reason, please refer to Figure 12 , Figure 12 ​This is a partial structural schematic diagram of another laser source provided in an embodiment of this application. The laser source 00 may further include a half-wave plate 008. The half-wave plate 008 can be located between the laser 000 and the first lens 0011. The half-wave plate 008 can be used to convert the incident blue and green laser light from S-polarized light to P-polarized light before directing it towards the first lens 0011, so that the polarization directions of the blue and green laser light entering the light guide 004 are the same as the polarization direction of the red laser. In this way, using laser light with a uniform polarization direction to form a projected image can avoid the problem of color blocks in the projected image caused by the different transmission and reflection efficiencies of optical lenses for different polarized light.

[0083] In the embodiments provided above, by setting half-wave plates in the light output paths of the blue and green lasers, and setting half-wave plates of corresponding wavelengths for the blue and green lasers respectively, the polarization directions of the blue and green lasers can be changed by 90 degrees. In this example, the polarization direction changes from S-polarization to P-polarization, which is consistent with the polarization direction of the red laser. Thus, when the blue and green lasers, which are now P-polarized, are reflected into the human eye through the same optical imaging system and projection screen, the transmittance of the P-polarized blue and green lasers in the optical lens is comparable to that of the P-polarized red laser. The consistency of the light processing is close, and the difference in reflectivity of the projection screen to the three primary colors is also reduced. The consistency of the light processing of the three primary colors in the entire projection system is improved, which can fundamentally eliminate the color deviation phenomenon of "color spots" and "color blocks" in local areas of the projected image and improve the display quality of the projected image.

[0084] Furthermore, since the transmittance of optical lenses in an optical system for P-polarized light is usually greater than that for S-polarized light, and the reflectance of the projection screen used in this example for P-polarized light is also greater than that for S-polarized light, by converting the blue and green lasers of S-polarized light into P-polarized light, so that the red, green, and blue lasers are all P-light, the light transmission efficiency of the projection beam in the entire system can be improved, the brightness of the entire projection screen can be increased, and the quality of the projection screen can be improved.

[0085] In summary, the laser provided by the embodiment of the present application comprises a substrate and a plurality of laser units arranged in an array on the substrate. In the present application, the laser comprises two rows of laser units, one row of red laser units for emitting red laser, and the other row of green laser units for emitting green laser and blue laser units for emitting blue laser. Under the premise of ensuring the brightness of the laser beam emitted by the laser, the number of laser units in the laser is reduced. In this way, the overall volume of the laser can be effectively reduced, thereby making the volume of the laser projection device smaller. In addition, the end of the laser units containing the blue laser units and the green laser units is a blue laser unit. In this way, the perception effect of the human eye after the three colors of laser light are combined can be effectively improved.

[0086] Figure 13 is a structural schematic diagram of a laser projection device provided by the embodiment of the present application. The laser projection device can comprise a laser light source 000, a lens group 001, a prism group 002, a light valve 003 and a projection lens 004. The laser light source 000 can be Figure 7 、 Figure 10 、 Figure 11 or Figure 12 the laser light source shown in the figure. Figure 11 The laser projection device comprises Figure 11 The laser light source 000 shown in the figure is taken as an example for description.

[0087] The lens group 001 can be located on the side of the light guide pipe 004 away from the light combination mirror group 001, and the prism group 002 and the light valve 003 can be located on the side of the lens group 001 away from the light guide pipe 004. Among them, the lens group 001 can be used to guide the laser beam emitted from the light guide pipe 004 to the prism group 002, and the prism group 002 can comprise a total internal reflection (English: Total Internal Reflection prism, abbreviated as: TIR) prism. The prism group 002 can be used to guide the laser beam to the light valve 003, and the light valve 003 can be used to modulate the laser beam and then guide it to the projection lens 004.

[0088] For example, the light valve 003 can comprise a plurality of reflective sheets (not shown in the figure), each reflective sheet can be used to form a pixel in the projection picture, and the light valve 003 can make the reflective sheet corresponding to the pixel which needs to be displayed in a bright state to reflect the laser to the projection lens 004 according to the image to be displayed, so as to realize the modulation of the laser beam. For example, the light valve 003 can be a digital micromirror device (English: Digital Micromirror Device; abbreviated as: DMD).

[0089] The laser beam emitted from the laser 000 can be along Figure 13The laser light emitted by the laser light source 00 can be shaped by the shaping lens group 002, so that the width of the light spot of the shaped laser light beam in the slow axis direction of the laser light is smaller, and the difference between the width of the light spot of the shaped laser light beam in the slow axis direction of the laser light and the width of the light spot of the shaped laser light beam in the fast axis direction of the laser light is smaller. In this way, the expansion loss of the laser light beam in the short side direction of the light spot can be effectively reduced. Further, the interference of the laser light used for projection is weak, which can weaken the speckle effect of the laser projection device during projection display, avoid the projection image from being distorted, improve the display effect of the projection image, and avoid the dizziness of the human eye during viewing.

[0090] In the embodiments of the present application, the shaping lens group 002 is arranged in the laser light source 00, so that the laser light source can shape the light beam combined by the light combining lens group 001 through the shaping lens group 002. The width of the light spot of the shaped laser light beam in the slow axis direction of the laser light is smaller, and the difference between the width of the light spot of the shaped laser light beam in the slow axis direction of the laser light and the width of the light spot of the shaped laser light beam in the fast axis direction of the laser light is smaller. In this way, the expansion loss of the laser light beam in the short side direction of the light spot can be effectively reduced. Further, the interference of the laser light used for projection is weak, which can weaken the speckle effect of the laser projection device during projection display, avoid the projection image from being distorted, improve the display effect of the projection image, and avoid the dizziness of the human eye during viewing.

[0091] In the present application, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance. The term "a plurality of" refers to two or more, unless otherwise explicitly limited.

[0092] The above description is only optional embodiments of the present application, and does not limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A laser characterized by, The laser device comprises: a substrate and a plurality of laser units arranged in an array on the substrate; wherein the plurality of laser units are arranged in two rows, each laser unit in one row is a red laser unit for emitting red laser light, and each laser unit in the other row is a green laser unit for emitting green laser light or a blue laser unit for emitting blue laser light, and the two end laser units in the other row are both blue laser units, at least one blue laser unit is arranged between the two end blue laser units, and the at least one blue laser unit is arranged between two green laser units. The laser device further comprises three first conductive pins and one second conductive pin on the substrate; the light emitting power ranges of the red laser units, the green laser units and the blue laser units are all different, the plurality of red laser units are connected in series, the plurality of green laser units are connected in series, and the plurality of blue laser units are connected in series. The three first conductive pins are respectively connected to the first ends of the plurality of red laser units connected in series, the first ends of the plurality of green laser units connected in series, and the first ends of the plurality of blue laser units connected in series. The one second conductive pin is connected to the second ends of the plurality of red laser units connected in series, the second ends of the plurality of green laser units connected in series, and the second ends of the plurality of blue laser units connected in series. One of the first conductive pins and the second conductive pin is a positive pin, and the other is a negative pin.

2. The laser of claim 1, wherein, In one row of the red laser units, the central wavelengths of the red laser light emitted by the red laser units gradually increase from both sides to the middle.

3. The laser of claim 2, wherein, In one row of the red laser units, there are at least one first red laser unit in a central region and at least two second red laser units on both sides of the at least one first red laser unit. The central wavelengths of the first red laser units are all the same, and the central wavelengths of the two second red laser units with the same distance from the central region are the same.

4. The laser of any of claims 1 to 3, wherein, The number of the red laser units is seven, the number of the green laser units is four, and the number of the blue laser units is three.

5. A laser light source, characterized by, The laser device, the light combining lens group, the light shaping lens group, the lens assembly, and the light guide pipe of any one of claims 1 to 4; The light combining lens group is located on the light emitting side of the laser device, and the arrangement direction of the laser device and the light combining lens group is perpendicular to the arrangement direction of the light combining lens group, the light shaping lens group, the lens assembly, and the light guide pipe; The laser device is used to emit three colors of laser light to the light combining lens group; The light combining lens group is used to combine the three colors of laser light and then guide the combined laser light to the light shaping lens group; The light shaping lens group is used to shape the combined laser light beam, so that the width of the light spot of the shaped laser light beam in the slow axis direction of the laser light is less than the width of the light spot of the unshaped laser light beam in the slow axis direction. ​ The shaping mirror group is also used for guiding the shaped laser beam to the lens assembly, the lens assembly is used for adjusting the laser beam and guiding the adjusted laser beam to the light guide pipe.

6. The laser light source according to claim 5, characterized by The shaping mirror group has a first cylindrical surface and a second cylindrical surface, the first cylindrical surface is closer to the light combination mirror group than the second cylindrical surface; The shaping mirror group is used for converging the combined laser beam in the slow axis direction through the first cylindrical surface, and is also used for collimating the converged laser beam through the second cylindrical surface to obtain the shaped laser beam.

7. The laser light source according to claim 6, characterized by The shaping mirror group comprises two cylindrical lenses, the arrangement direction of the two cylindrical lenses is perpendicular to the arrangement direction of the laser and the light combination mirror group, and the cylindrical lens closer to the light combination mirror group of the two cylindrical lenses has the first cylindrical surface, and the cylindrical lens closer to the light guide pipe of the two cylindrical lenses has the second cylindrical surface; The laser light source further comprises a plane mirror, the plane mirror is located between the two cylindrical lenses, and the plane mirror is used for adjusting the direction of the laser beam emitted by the cylindrical lens closer to the light combination mirror group of the two cylindrical lenses to be towards the cylindrical lens closer to the light guide pipe of the two cylindrical lenses.

8. A laser projection device, comprising: Comprise: The laser light source, the light valve and the projection lens according to any one of claims 5 to 7.

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