Laser beam combining device and projector

Abstract

The utility model relates to a laser beam combining device and a projector, the laser beam combining device comprises a first laser assembly, a second laser assembly and a beam combining structure, and the first laser assembly comprises a first green laser and a first blue laser; the second laser assembly comprises a second green laser and a second blue laser; the beam combining structure is used for combining light output by the first laser assembly and light output by the second laser assembly, the beam combining structure comprises a partition diaphragm, the partition diaphragm comprises a first area and a second area which are connected, and blue light output by the first blue light laser device and green light output by the second green light laser device are combined through the first area and then output through the second area; and green light output by the first green light laser and blue light output by the second blue light laser are combined through the second area. According to the invention, by arranging the partition diaphragm, the blue light and the green light of the first laser assembly and the second laser assembly are combined on the same partition diaphragm, so that the optical expansion amount of the combined light is greatly reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of laser beam combination, in particular to a laser beam combination device and a projector. BACKGROUND

[0002] The principle of laser beam combination is to combine the outputs of multiple laser light sources into a single output beam. The purpose of beam combination is not only to simply increase the output power, but also to maintain the beam quality of the output beam. In the existing beam combination method, two laser components output through spatial stacking, resulting in the optical etendue of the combined light of the two laser components being more than twice that of a single laser component. The overall optical system volume increases with the increase of the optical etendue, and the optical system needs to be adjusted to adapt to the increase of the optical etendue of the combined light, affecting the efficiency of the optical system. CONTENT OF THE UTILITY MODEL

[0003] The embodiment of the present application provides a laser beam combination device, which comprises: a first laser component, the first laser component comprising a first green laser and a first blue laser; a second laser component, the second laser component comprising a second green laser and a second blue laser; a beam combination structure, the beam combination structure being used for combining the light output by the first laser component and the light output by the second laser component; wherein the beam combination structure comprises a partition film, the partition film comprising a first region and a second region connected to each other, blue light output by the first blue laser and green light output by the second green laser are combined through the first region, and green light output by the first green laser and blue light output by the second blue laser are combined through the second region.

[0004] According to an embodiment of the present application, the beam combination structure further comprises a half-wave plate and a polarization beam combiner, the first laser component further comprises a first red laser, the second laser component further comprises a second red laser, and the half-wave plate is located between the polarization beam combiner and the second red laser; the red light output by the first red laser and the second red laser is all P-polarized light, the P-polarized light output by the second red laser is transmitted through the half-wave plate to form S-polarized light, the polarization beam combiner is configured to reflect S-polarized light and transmit P-polarized light, and the P-polarized light output by the first red laser and the S-polarized light transmitted by the half-wave plate are combined through the polarization beam combiner, or the red light output by the first red laser and the second red laser is all S-polarized light, the S-polarized light output by the second red laser is transmitted through the half-wave plate to form P-polarized light, the polarization beam combiner is configured to reflect P-polarized light and transmit S-polarized light, and the S-polarized light output by the first red laser and the P-polarized light transmitted by the half-wave plate are combined through the polarization beam combiner.

[0005] According to an embodiment of the present application, the first area is covered with a green light reflecting and red and blue light transmitting film configured to reflect green light and transmit red and blue light; the second area is covered with a blue light reflecting and red and green light transmitting film configured to reflect blue light and transmit red and green light; the beam combining structure further comprises a red light transmitting and blue and green light reflecting mirror configured to transmit red light and reflect blue and green light, and the polarized light combining mirror combined light, the green light output by the first green light laser, and the blue light output by the first blue light laser are combined by the red light transmitting and blue and green light reflecting mirror; the polarized light combining mirror combined light, the green light output by the second green light laser, and the blue light output by the second blue light laser are combined by the partition film.

[0006] According to an embodiment of the present application, the beam combining structure further comprises a first mirror for reflecting the red light output by the first red light laser to the polarized light combining mirror; the first laser assembly and the second laser assembly are located on two sides of the beam combining structure, and the first mirror, the polarized light combining mirror, the red light transmitting and blue and green light reflecting mirror, and the partition film are arranged side by side in sequence.

[0007] According to an embodiment of the present application, the center of the first mirror, the center of the polarized light combining mirror, the center of the red light transmitting and blue and green light reflecting mirror, and the center of the partition film are located on a first axis, and the first mirror, the polarized light combining mirror, the red light transmitting and blue and green light reflecting mirror, and the partition film form a 45-degree angle with the first axis.

[0008] According to an embodiment of the present application, the first area is covered with a green light reflecting and blue light transmitting film configured to reflect green light and transmit blue light; the second area is covered with a blue light reflecting and green light transmitting film configured to reflect blue light and transmit green light; the beam combining structure further comprises a red light transmitting and blue and green light reflecting mirror configured to transmit red light and reflect blue and green light, and the polarized light combining mirror combined light and the partition film combined light are combined by the red light transmitting and blue and green light reflecting mirror.

[0009] According to an embodiment of the present application, the beam combining structure further comprises a first mirror for reflecting the red light output by the first red light laser to the polarized light combining mirror, and a second mirror for reflecting the green light output by the first green light laser and the blue light output by the first blue light laser to the partition film; the first laser assembly and the second laser assembly are located on the same side of the beam combining structure, the first mirror, the polarized light combining mirror, and the red light transmitting and blue and green light reflecting mirror are arranged side by side in sequence, and the partition film is located between the red light transmitting and blue and green light reflecting mirror and the second laser assembly.

[0010] According to an embodiment of the present application, the center of the first reflector, the center of the polarization combiner, and the center of the red-transmitting blue-green reflecting mirror are all located on a second axis; the center of the second reflector and the center of the partitioned film are both located on a third axis; the second axis and the third axis are arranged in parallel and at intervals, and the first laser assembly and the second laser assembly are arranged on a side of the third axis away from the second axis; the first reflector, the polarization combiner, and the red-transmitting blue-green reflecting mirror all form a 45-degree angle with the second axis; and the second reflector and the partitioned film both form a 45-degree angle with the third axis.

[0011] According to an embodiment of the present application, the first green laser and the first blue laser are fixedly connected, and the second green laser and the second blue laser are fixedly connected.

[0012] The present application further provides a projector, which comprises the laser beam combining device described in the above embodiments.

[0013] The laser beam combining device and the projector provided by the present application can combine the blue light and the green light output by the first laser assembly and the second laser assembly on the same partitioned film by arranging the first region and the second region connected on the partitioned film, so that the optical etendue of the combined light is greatly reduced. Reducing the optical etendue is beneficial to reducing the volume of the optical system and improving the use efficiency of the optical system. BRIEF DESCRIPTION OF DRAWINGS

[0014] 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 effort.

[0015] Figure 1 is a structural schematic diagram of a laser beam combining device in the prior art;

[0016] Figure 2 is a structural schematic diagram of an embodiment of the laser beam combining device of the present application;

[0017] Figure 3 is a structural schematic diagram of another embodiment of the laser beam combining device of the present application;

[0018] Figure 4 is Figure 2 a structural schematic diagram of a partitioned film of the laser beam combining device shown in FIG. 8;

[0019] Figure 5 is a structural schematic diagram of still another embodiment of the laser beam combining device of the present application;

[0020] Figure 6 Figure 1 is a schematic diagram of an embodiment of a projector of the present application. DETAILED DESCRIPTION

[0021] The present application will be further described by examples with reference to the drawings accompanying. It is particularly pointed out that the following examples are only for illustrating the present application, but not for limiting the scope of the present application. Similarly, the following examples are only part of the embodiments of the present application, but not all the embodiments of the present application, all other embodiments obtained by those skilled in the art without doing creative work are within the scope of the present application.

[0022] The terms "first", "second", "third" in the embodiments of the present application are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second", "third" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited. All directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only for explaining the relative position relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), if the certain posture changes, the directional indications also change accordingly. The terms "include" and "have" and any variations thereof in the embodiments of the present application are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or components inherent to the process, method, product or device.

[0023] Reference to "embodiments" in this document means that the specific features, structures or properties described in connection with the embodiments can be included in at least one embodiment of the present application. The phrase appears at various places in the specification does not necessarily mean the same embodiment, nor is it independent or alternative to other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0024] Laser beam combining is a process of coupling multiple single unit laser beams into one beam. In the existing technical solutions, such as Figure 1As shown, the third laser assembly 100 and the fourth laser assembly 200 of the laser beam combining device output light to be combined by two light combining plates 300 respectively, and the combined light is output by a spatial stacking mode, resulting in that the optical etendue of the combined light of the third laser assembly 100 and the fourth laser assembly 200 is more than twice of a laser assembly, the spatial distribution of the spot (cross-sectional area) of the combined light is 7.6mm*8mm, the spot of the combined light is enlarged, the focal length of the lenses in the optical system also needs to be correspondingly lengthened, so that the overall optical system is enlarged with the increase of the optical etendue of the combined light, and the optical system needs to be adjusted to adapt to the increase of the spot of the combined light, affecting the efficiency of the optical system. The optical etendue is an important concept in non-imaging optics, which is used to describe the geometric characteristics of a light beam with a certain aperture angle and cross-sectional area.

[0025] The embodiment of the present application provides a laser beam combining device, as shown in Figure 2 and Figure 4 As shown, the laser beam combining device comprises a first laser assembly 10, a second laser assembly 20 and a beam combining structure 30, the first laser assembly 10 comprises a first green laser 110 and a first blue laser 120; the second laser assembly 20 comprises a second green laser 210 and a second blue laser 220; the beam combining structure 30 is used for combining the light output by the first laser assembly 10 and the light output by the second laser assembly 20, and the beam combining structure 30 comprises a partitioned film 310, the partitioned film 310 comprises a first region 311 and a second region 312 connected with each other, the blue light output by the first blue laser 120 and the green light output by the second green laser 210 are combined through the first region 311, and the green light output by the first green laser 110 and the blue light output by the second blue laser 220 are combined through the second region 312. The partitioned film 310 of the present application is provided with the first region 311 and the second region 312 connected with each other, so that the blue light output by the first blue laser 120 and the green light output by the second green laser 210, and the green light output by the first green laser 110 and the blue light output by the second blue laser 220 can be combined on one partitioned film 310, which greatly reduces the optical etendue of the combined light, is conducive to reducing the volume of the optical system, and improves the use efficiency of the optical system.

[0026] In some embodiments, the first green laser 110 and the first blue laser 120 are fixedly connected, and the second green laser 210 and the second blue laser 220 are fixedly connected. Specifically, the first green laser 110 and the first blue laser 120 are co-packaged, and the second green laser 210 and the second blue laser 220 are co-packaged. The co-packaging (Co-packaged) is a technology of assembling multiple components in the same package, and the use of the co-packaging technology can reduce the size of the laser assembly, simplify the design and improve the reliability.

[0027] In some embodiments, as shown in FIG. 1, the first laser assembly 10 further comprises a first red laser 130, and the second laser assembly 20 further comprises a second red laser 230. The first red laser 130 is fixed relative to the first green laser 110 and the first blue laser 120, and the second red laser 230 is fixed relative to the second green laser 210 and the second blue laser 220. Specifically, the first red laser 130, the first green laser 110, and the first blue laser 120 are integrated into the first laser assembly 10, and the second red laser 230, the second green laser 210, and the second blue laser 220 are integrated into the second laser assembly 20. Figure 3

[0028] In some embodiments, the first red laser 130 is spaced apart from the co-packaged first green laser 110 and the first blue laser 120, and the second red laser 230 is spaced apart from the co-packaged second green laser 210 and the second blue laser 220. Since the wavelength range of blue-green lasers is between 450-570 nanometers, and the wavelength of red light is about 630-750 nanometers. This wavelength difference results in different propagation characteristics in the optical system, and red light is sensitive to temperature, making it difficult to achieve good coupling and focusing in the same package. Therefore, red light is generally not co-packaged with blue-green lasers.

[0029] In some embodiments, the lasers of the first laser assembly 10 and the second laser assembly 20 can be semiconductor lasers. In other embodiments, the lasers of the first laser assembly 10 and the second laser assembly 20 can also be solid-state lasers or other types of lasers such as gas lasers.

[0030] In some embodiments, the first red laser 130, the first green laser 110, and the first blue laser 120 are arranged in sequence and side by side, and the directions of the light output by the three lasers are the same. The second red laser 230, the second green laser 210, and the second blue laser 220 are arranged in sequence and side by side, and the directions of the light output by the three lasers are the same.

[0031] In some embodiments, the first laser assembly 10 and the second laser assembly 20 are respectively located on the two sides of the beam combining structure 30, the directions of the light output by the first laser assembly 10 and the second laser assembly 20 are opposite, the spacing space between the first red laser 130 and the first green laser 110 corresponds to the position of the second red laser 230, and the spacing space between the second red laser 230 and the second green laser 210 corresponds to the positions of the first green laser 110 and the first blue laser 120 which are fixedly connected.

[0032] ​In some embodiments, the beam combining structure 30 further comprises a half-wave plate 320 and a polarization beam combiner 330, the half-wave plate 320 is located between the polarization beam combiner 330 and the second red laser 230, the red light output by the first red laser 130 and the second red laser 230 is P-polarized light, the P-polarized light output by the second red laser 230 is transmitted by the half-wave plate 320 to form S-polarized light, the polarization beam combiner 330 is configured to reflect S-polarized light and transmit P-polarized light, and the P-polarized light output by the first red laser 130 and the S-polarized light transmitted by the half-wave plate 320 are combined by the polarization beam combiner 330.

[0033] In some other embodiments, the red light output by the first red laser 130 and the second red laser 230 is S-polarized light, the S-polarized light output by the second red laser 230 is transmitted by the half-wave plate 320 to form P-polarized light, and the polarization beam combiner 330 is configured to reflect P-polarized light and transmit S-polarized light, and the S-polarized light output by the first red laser 130 and the P-polarized light transmitted by the half-wave plate 320 are combined by the polarization beam combiner 330.

[0034] The first laser assembly 10 and the second laser assembly 20 can be the same laser assembly, and the red light of the same polarization state is easy to interfere when combined, and then laser speckle occurs. The present application converts the P-polarized light output by the second red laser 230 into S-polarized light by arranging the half-wave plate 320, and since the S-polarized light and the P-polarized light are orthogonal in polarization, the interference of coherent light can be effectively reduced, thereby reducing the formation of speckle. The optical expansion of the combined red light is nearly half of that of the prior art, and the P-polarized light and the S-polarized light of the red light each accounts for half of the proportion.

[0035] Specifically, the polarization beam combiner 330 can reflect S-polarized light and transmit P-polarized light, and the polarization beam combiner 330 can be a polarization beam combining prism or a thin film type polarization beam splitter. The red light output by the second red laser 230 can pass through the half-wave plate 320 and be reflected by the polarization beam combiner 330, and the red light output by the first red laser 130 can be transmitted by the polarization beam combiner 330 to achieve the combination of P-polarized light and S-polarized light.

[0036] In some embodiments, the beam combining structure 30 further comprises a red-transmitting blue-green reflecting mirror 340, the red-transmitting blue-green reflecting mirror 340 is configured to transmit red light and reflect blue light and green light, and the combined light of the polarization beam combiner 330, the green light output by the first green laser 110, and the blue light output by the first blue laser 120 are combined by the red-transmitting blue-green reflecting mirror 340.

[0037] Specifically, the red-transmitting blue-green-reflecting mirror 340 can be an optical lens coated with a red-transmitting blue-green-reflecting film. The combined light of the polarization-combining mirror 330 is red light, which can be transmitted by the red-transmitting blue-green-reflecting mirror 340. The green light output by the first green laser 110 and the blue light output by the first blue laser 120 can be reflected by the red-transmitting blue-green-reflecting mirror 340.

[0038] In some embodiments, the first area 311 of the partitioned film 310 is coated with a green-reflecting red-blue-transmitting film configured to reflect green light and transmit red light and blue light. The second area 312 is coated with a blue-reflecting red-green-transmitting film configured to reflect blue light and transmit red light and green light.

[0039] Specifically, the partitioned film 310 can be formed by optical coating on a glass substrate. Optical coating refers to a process of coating a layer (or multiple layers) of metal (or dielectric) film on the surface of an optical part. The purpose of coating the surface of the optical part is to achieve the requirements of reducing or increasing light reflection, beam splitting, color separation, light filtering, polarization, etc. Common coating methods include vacuum coating (one of physical coating methods) and chemical coating. The coating material of optical coating can be metal oxides such as silicon dioxide (SiO2), aluminum oxide (Al2O3), or titanium oxide (TiO2), etc. It can also be metal fluorides such as magnesium fluoride (MgF2) or calcium fluoride (CaF2), etc. It can also be gold (Au), silver (Ag), aluminum (Al), etc.

[0040] In some embodiments, the method of forming the first area 311 and the second area 312 of the partitioned film 310 can be as follows. First, the first area 311 is covered by silk-screening protective ink on one side of the glass substrate. Then, the area coating is performed on the single side of the glass substrate except the first area 311 (i.e., the second area 312). After the coating is completed, the second area 312 is required to meet the corresponding optical requirements. Then, the first area 311 is cleaned and the protective ink is removed. Next, the second area 312 is covered by silk-screening protective ink, and the area coating is performed on the first area 311 of the single side of the glass substrate. After the coating is completed, the second area 312 is cleaned and the protective ink is removed. As a result, the same glass substrate has different optical properties in different areas.

[0041] In some embodiments, the combined light of the red-transmitting blue-green-reflecting mirror 340, the green light output by the second green laser 210, and the blue light output by the second blue laser 220 are combined by the partitioned film 310.

[0042] Specifically, the blue light output by the first blue laser 120 can be reflected by the red-transmitting blue-green-reflecting mirror 340 and transmitted through the first region 311, the green light output by the first green laser 110 can be reflected by the red-transmitting blue-green-reflecting mirror 340 and transmitted through the second region 312, the green light output by the second green laser 210 can be reflected by the first region 311, the blue light output by the second blue laser 220 can be reflected by the second region 312, the red light transmitted by the red-transmitting blue-green-reflecting mirror 340 can be transmitted through the partition film 310, and finally the three-color laser beams of the first laser assembly 10 and the second laser assembly 20 are combined through the partition film 310.

[0043] In some embodiments, the red light transmitted by the red-transmitting blue-green-reflecting mirror 340 can be transmitted through the middle of the partition film 310, and the first region 311 and the second region 312 of the partition film 310 need to be tightly connected to avoid the influence of the connection gap on the transmission of the red light.

[0044] In some embodiments, the partition film 310 can be divided into the first region 311 and the second region 312, and the areas of the first region 311 and the second region 312 can be the same.

[0045] In some embodiments, the beam combining structure 30 further comprises a first reflecting mirror 350, which is used to reflect the red light output by the first red laser 130 to the polarization combining mirror 330.

[0046] In some embodiments, the first reflecting mirror 350, the polarization combining mirror 330, the red-transmitting blue-green-reflecting mirror 340, and the partition film 310 are arranged side by side in sequence.

[0047] In some embodiments, the center of the first reflecting mirror 350, the center of the polarization combining mirror 330, the center of the red-transmitting blue-green-reflecting mirror 340, and the center of the partition film 310 are all located on the first axis 301, so as to reduce the volume of the beam combining structure 30. The lasers of the first laser assembly 10 and the lasers of the second laser assembly 20 are arranged side by side on both sides of the first axis 301, so as to reduce the volume of the laser beam combining device.

[0048] Specifically, the angles between the first reflecting mirror 350, the polarizing beam combiner 330, the red-transmitting and blue-green-reflecting mirror 340, the partitioning diaphragm 310, and the first axis 301 can all be 45 degrees. Further, the first reflecting mirror 350 and the polarizing beam combiner 330 are perpendicular, the polarizing beam combiner 330 and the red-transmitting and blue-green-reflecting mirror 340 are perpendicular, and the red-transmitting and blue-green-reflecting mirror 340 and the partitioning diaphragm 310 are perpendicular. The first red laser 130 is located on the side of the first reflector 350 away from the second laser assembly 20. The second red laser 230 is located on the side of the polarizing beam combiner 330 away from the first laser assembly 10. The half-wave plate 320 is disposed between the polarizing beam combiner 330 and the second red laser 230. The first green laser 110 and the first blue laser 120, which are co-encapsulated, are located on the side of the red-transmitting and blue-green-reflecting mirror 340 away from the second laser assembly 20. The second green laser 210 is located on the side of the first region 311 away from the first laser assembly 10. The second blue laser 220 is located on the side of the second region 312 away from the first laser assembly 10.

[0049] The red light output from the first red laser 130 is incident at a 45-degree angle on the first reflecting mirror 350, and is subsequently reflected by the first reflecting mirror 350, transmitted through the polarizing beam combiner 330, transmitted through the red-transmitting-blue-green mirror 340, and transmitted through the partitioned film 310. The green light output from the first green laser 110 is incident at a 45-degree angle on the red-transmitting-blue-green mirror 340, and is subsequently reflected by the red-transmitting-blue-green mirror 340 and transmitted through the second region 312. The blue light output from the first blue laser 120 is incident at a 45-degree angle on the red-transmitting-blue-green mirror 340, and is subsequently reflected by the red-transmitting-blue-green mirror 340 and transmitted through the second region 312. The first region 311 transmits the red light output from the second red laser 230 through the half-wave plate 320, and then incident at a 45-degree angle on the polarizing beam combiner 330. The light is then reflected by the polarizing beam combiner 330, transmitted through the red-transmitting, blue-green-reflecting mirror 340, and transmitted through the partitioned diaphragm 310. The green light output from the second green laser 210 is incident at a 45-degree angle on the first region 311 and reflected by it. The blue light output from the second blue laser 220 is incident at a 45-degree angle on the second region 312 and reflected by it. Through this optical path design, the light output from the first laser assembly 10 and the second laser assembly 20 is converged onto the partitioned diaphragm 310, effectively reducing the optical spread of the combined beam formed by the partitioned diaphragm 310.

[0050] In some embodiments, such as Figure 5 As shown, the first laser component 10 and the second laser component 20 are located on the same side of the beam combining structure 30. The first blue laser 120, the first green laser 110, the first red laser 130, the second red laser 230, the second green laser 210 and the second blue laser 220 are arranged side by side in sequence, and the directions of the light output by the above lasers are the same.

[0051] In some embodiments, the first region 311 of the partitioned film 310 is covered with a reverse green and blue light transmitting film configured to reflect green light and transmit blue light, and the second region 312 is covered with a reverse blue and green light transmitting film configured to reflect blue light and transmit green light.

[0052] In some embodiments, the combined light of the polarization combiner 330 and the combined light of the partitioned film 310 are combined by the red light transmitting and blue-green light reflecting mirror 340.

[0053] Specifically, the blue light output by the first blue light laser 120 can be reflected by the first region 311 to the red light transmitting and blue-green light reflecting mirror 340 and reflected by the red light transmitting and blue-green light reflecting mirror 340; the green light output by the first green light laser 110 can be reflected by the second region 312 to the red light transmitting and blue-green light reflecting mirror 340 and reflected by the red light transmitting and blue-green light reflecting mirror 340; the green light output by the second green light laser 210 can be transmitted by the first region 311 to the red light transmitting and blue-green light reflecting mirror 340 and reflected by the red light transmitting and blue-green light reflecting mirror 340; the blue light output by the second blue light laser 220 can be transmitted by the second region 312 to the red light transmitting and blue-green light reflecting mirror 340 and reflected by the red light transmitting and blue-green light reflecting mirror 340; finally, the red light transmitting and blue-green light reflecting mirror 340 is used to combine the three-color laser beams of the first laser assembly 10 and the second laser assembly 20.

[0054] In some embodiments, the combining structure 30 further comprises a first mirror 350 and a second mirror 360, the first mirror 350 is used to reflect the red light output by the first red light laser 130 to the polarization combiner 330, and the second mirror 360 is used to reflect the green light output by the first green light laser 110 and the blue light output by the first blue light laser 120 to the partitioned film 310.

[0055] In some embodiments, the first mirror 350, the polarization combiner 330, and the red light transmitting and blue-green light reflecting mirror 340 are arranged side by side in sequence, and the second mirror 360 and the partitioned film 310 are arranged side by side.

[0056] In some embodiments, the center of the first mirror 350, the center of the polarization combiner 330, and the center of the red light transmitting and blue-green light reflecting mirror 340 are all located on the second axis 302, the center of the second mirror 360 and the center of the partitioned film 310 are all located on the third axis 303, the second axis 302 and the third axis 303 are arranged in parallel and spaced apart, and the first laser assembly 10 and the second laser assembly 20 are arranged side by side on the side of the third axis 303 away from the second axis 302, so as to reduce the volume of the laser beam combining device.

[0057] Specifically, the included angle between the first mirror 350, the polarization combining mirror 330, the red-transmitting blue-green-reflection mirror 340 and the second axis 302 can all be 45 degrees, and the included angle between the second mirror 360 and the partition film 310 and the third axis 303 can all be 45 degrees. Further, any two of the first mirror 350, the polarization combining mirror 330, the red-transmitting blue-green-reflection mirror 340, the second mirror 360 and the partition film 310 are parallel to each other. The first blue laser 120 and the first green laser 110 of the co-packaged first laser assembly are located on the side of the second mirror 360 away from the second axis 302, the first red laser 130 and the first mirror 350 are oppositely arranged on both sides of the third axis 303, the second red laser 230 and the polarization combining mirror 330 are oppositely arranged on both sides of the third axis 303, the half-wave plate 320 is arranged between the second red laser 230 and the polarization combining mirror 330, and the second green laser 210 and the second blue laser 220 of the co-packaged second laser assembly are arranged on the side of the partition film 310 away from the red-transmitting blue-green-reflection mirror 340.

[0058] The blue light output by the first blue laser 120 is incident on the second mirror 360 at an angle of 45 degrees, and is reflected by the second mirror 360, the first region 311 and the red-transmitting blue-green-reflection mirror 340 in sequence. The green light output by the first green laser 110 is incident on the second mirror 360 at an angle of 45 degrees, and is reflected by the second mirror 360, the second region 312 and the red-transmitting blue-green-reflection mirror 340 in sequence. The red light output by the first red laser 130 is incident on the first mirror 350 at an angle of 45 degrees, and is reflected by the first mirror 350, transmitted by the polarization combining mirror 330 and transmitted by the red-transmitting blue-green-reflection mirror 340 in sequence. The red light output by the second red laser 230 is transmitted by the half-wave plate 320, and is incident on the polarization combining mirror 330 at an angle of 45 degrees, and is reflected by the polarization combining mirror 330 and transmitted by the red-transmitting blue-green-reflection mirror 340 in sequence. The green light output by the second green laser 210 is transmitted by the first region 311, and is reflected by the red-transmitting blue-green-reflection mirror 340. The blue light output by the second blue laser 220 is transmitted by the second region 312, and is reflected by the red-transmitting blue-green-reflection mirror 340. Through the above optical path design, the light output by the first laser assembly 10 and the second laser assembly 20 is converged to the red-transmitting blue-green-reflection mirror 340, and the optical etendue of the combined light formed by the red-transmitting blue-green-reflection mirror 340 can be effectively reduced.

[0059] Through the above laser beam combining device, the spatial distribution of the spot of the combined light formed by the red light, the green light and the blue light of the first laser assembly 10 and the second laser assembly 20 is 7mm*3.2mm, and the optical etendue is reduced to 36.8% of the existing scheme.

[0060] The embodiment of the present application also provides a projector, which comprises the laser beam combining device. Figure 6As shown, the projector comprises the laser beam combining device in the above-described embodiments.

[0061] In some embodiments, the projector further comprises a housing 40, a speckle suppression system, a light homogenizing device, a light valve, an imaging system, and the laser beam combining device is arranged in the housing 40, the combined light emitted by the laser beam combining device passes through the speckle suppression system, the speckle of the laser light is effectively suppressed, passes through the light homogenizing device, and is projected to the light valve, and the imaging system amplifies the light valve to form a projection image.

[0062] The laser beam combining device and the projector provided by the application, by arranging the first region 311 and the second region 312 connected to each other on the partition film 310, the green light and the blue light output by the first laser assembly 10 and the second laser assembly 20 can be combined on the same partition film, by arranging the half-wave plate 320 and the polarization light combiner 330, the optical expansion of the combined light formed by the red light of the first red light laser 130 and the red light of the second red light laser 230 is reduced by nearly half, and the laser speckle can be effectively suppressed, by designing the light path, the optical expansion of the combined light combined by the laser beam combining device is greatly reduced, which is beneficial to improve the quality of the combined light, reduce the volume of the optical system, and improve the efficiency of the optical system.

[0063] The above only describes some embodiments of the application, and does not limit the protection scope of the application, and any equivalent device or equivalent flow conversion using the content of the specification and the drawings, or directly or indirectly applied to other related technical fields, are also included in the patent protection scope of the application.

Claims

1. A laser beam combining apparatus, characterized by, The application relates to a laser module. The laser module comprises: a first laser assembly comprising a first green laser and a first blue laser; a second laser assembly comprising a second green laser and a second blue laser; a beam combining structure for combining the light output by the first laser assembly and the light output by the second laser assembly; wherein 2. The laser beam combining apparatus of claim 1, wherein, the beam combining structure comprises a partitioned film comprising a first region and a second region connected to each other, the blue light output by the first blue laser and the green light output by the second green laser are combined through the first region, and the green light output by the first green laser and the blue light output by the second blue laser are combined through the second region. The beam combining structure further comprises a half-wave plate and a polarization beam combiner, the first laser assembly further comprises a first red laser, and the second laser assembly further comprises a second red laser, the half-wave plate is located between the polarization beam combiner and the second red laser; the red light output by the first red laser and the second red laser is P-polarized light, the P-polarized light output by the second red laser is transmitted through the half-wave plate to form S-polarized light, the polarization beam combiner is configured to reflect S-polarized light and transmit P-polarized light, and the P-polarized light output by the first red laser and the S-polarized light transmitted by the half-wave plate are combined through the polarization beam combiner, or 3. The laser beam combining apparatus of claim 2, wherein, the red light output by the first red laser and the second red laser is S-polarized light, the S-polarized light output by the second red laser is transmitted through the half-wave plate to form P-polarized light, the polarization beam combiner is configured to reflect P-polarized light and transmit S-polarized light, and the S-polarized light output by the first red laser and the P-polarized light transmitted by the half-wave plate are combined through the polarization beam combiner.

4. The laser beam combining apparatus of claim 3, wherein The first region is covered with a green-reflection red-transmission blue film configured to reflect green light and transmit red light and blue light, the second region is covered with a blue-reflection red-transmission green film configured to reflect blue light and transmit red light and green light, the beam combining structure further comprises a red-transmission blue-reflection green mirror configured to transmit red light and reflect blue light and green light, and the combined light of the polarization beam combiner, the green light output by the first green laser and the blue light output by the first blue laser are combined through the red-transmission blue-reflection green mirror, and the combined light of the red-transmission blue-reflection green mirror, the green light output by the second green laser and the blue light output by the second blue laser are combined through the partitioned film. The beam combining structure further comprises a first mirror for reflecting the red light output by the first red laser to the polarization beam combiner, the first laser assembly and the second laser assembly are located on two sides of the beam combining structure respectively, and the first mirror, the polarization beam combiner, the red-transmission blue-reflection green mirror and the partitioned film are arranged side by side in sequence.

5. The laser beam combining apparatus of claim 4, wherein, The center of the first mirror, the center of the polarization combiner, the center of the red-transmitting blue-reflection mirror, and the center of the partition film are located on the first axis; the first mirror, the polarization combiner, the red-transmitting blue-reflection mirror, and the partition film form a 45-degree angle with the first axis.

6. The laser beam combining apparatus of claim 2, wherein, The first region is covered with a green-reflection blue-transmission film configured to reflect green light and transmit blue light; the second region is covered with a blue-reflection green-transmission film configured to reflect blue light and transmit green light; the beam combining structure further comprises a red-transmitting blue-reflection mirror configured to transmit red light and reflect blue light and green light, and the beam combined by the polarization combiner and the beam combined by the partition film are combined by the red-transmitting blue-reflection mirror.

7. The laser beam combining apparatus of claim 6, wherein, The beam combining structure further comprises a first mirror for reflecting the red light output by the first red laser to the polarization combiner and a second mirror for reflecting the green light output by the first green laser and the blue light output by the first blue laser to the partition film; the first laser assembly and the second laser assembly are located on the same side of the beam combining structure, the first mirror, the polarization combiner, and the red-transmitting blue-reflection mirror are arranged side by side in sequence, and the partition film is located between the red-transmitting blue-reflection mirror and the second laser assembly.

8. The laser beam combining apparatus of claim 7, wherein, The center of the first mirror, the center of the polarization combiner, and the center of the red-transmitting blue-reflection mirror are located on the second axis; the center of the second mirror and the center of the partition film are located on the third axis; the second axis and the third axis are arranged in parallel and spaced apart, the first laser assembly and the second laser assembly are located on the side of the third axis away from the second axis; the first mirror, the polarization combiner, and the red-transmitting blue-reflection mirror form a 45-degree angle with the second axis; the second mirror and the partition film form a 45-degree angle with the third axis.

9. The laser beam combining apparatus of claim 1, wherein, The first green laser and the first blue laser are fixedly connected, and the second green laser and the second blue laser are fixedly connected.

10. A projector characterized by comprising: The laser beam combining device comprises the laser beam combining device according to any one of claims 1-9.

Images