Laser beam combining device and projector

Abstract

A laser beam combining device and a projector. 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 light outputted by the first laser assembly (10) and light outputted by the second laser assembly (20); 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 to each other; and blue light outputted by the first blue laser (120) and green light outputted by the second green laser (210) are combined by means of the first region (311), and green light outputted by the first green laser (110) and blue light outputted by the second blue laser (220) are combined by means of the second region (312). In the laser beam combining device and the projector, by providing the partitioned film (310), the blue light and green light of the first laser assembly (10) and the second laser assembly (20) are combined on the same partitioned film (310), thereby greatly reducing the etendue of the combined light.

Description

Laser beam combiner and projector

[0001] Cross-reference of related applications

[0002] This application claims priority to Chinese Utility Model Patent Application No. 202423229693X, filed on December 25, 2024, entitled "Laser Beam Combiner and Projector", the entire contents of which are incorporated herein by reference.

[0003] [Technical Field]

[0004] This application relates to the technical field of laser beam combining, specifically to a laser beam combining device and a projector.

[0005] [Background Technology]

[0006] Laser beam combining works by combining the outputs of multiple laser sources into a single beam. The goal of beam combining is not merely to multiply the output power, but also to maintain beam quality. Current beam combining methods involve spatially stacking two laser components, resulting in an optical spread of more than twice that of a single laser component. This increases the overall size of the optical system, requiring adjustments to accommodate the increased optical spread and impacting system efficiency.

[0007] [Summary of the Invention]

[0008] This application provides a laser beam combining device, comprising: a first laser component, the first laser component including a first green laser and a first blue laser; a second laser component, the second laser component including a second green laser and a second blue laser; and a beam combining structure, the beam combining structure being used to combine the light output from the first laser component and the light output from the second laser component; wherein, the beam combining structure includes a partitioned diaphragm, the partitioned diaphragm including a first region and a second region connected to each other, the blue light output from the first blue laser and the green light output from the second green laser being combined through the first region, and the green light output from the first green laser and the blue light output from the second blue laser being combined through the second region.

[0009] According to one embodiment of this application, the beam combining structure further includes a half-wave plate and a polarizing beam combiner. The first laser component further includes a first red laser, and the second laser component further includes a second red laser. The half-wave plate is located between the polarizing 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 polarizing beam combiner is configured to reflect S-polarized light and transmit P-polarized light. The polarized light is combined by the polarization combining mirror, whereby the P-polarized light output from the first red laser and the S-polarized light transmitted through the half-wave plate are combined; or, the red light output from both the first and second red lasers is S-polarized light, and the S-polarized light output from the second red laser is transmitted through the half-wave plate to form P-polarized light. The polarization combining mirror is configured to reflect P-polarized light and transmit S-polarized light, and the S-polarized light output from the first red laser and the P-polarized light transmitted through the half-wave plate are combined by the polarization combining mirror.

[0010] According to one embodiment of this application, the first region is covered with a green-reflecting, red-transmitting, and blue-transmitting film, which is configured to reflect green light and transmit red and blue light; the second region is covered with a blue-reflecting, red-transmitting, and green-transmitting film, which is configured to reflect blue light and transmit red and green light; the beam combining structure further includes a red-transmitting, blue-reflecting, and green-transmitting mirror, which is configured to transmit red light and reflect blue and green light; the beam combined by the polarizing beam combiner, the green light output by the first green laser, and the blue light output by the first blue laser are combined by the red-transmitting, blue-reflecting, and green-transmitting mirror; the beam combined by the red-transmitting, blue-reflecting, and green-transmitting mirror, the green light output by the second green laser, and the blue light output by the second blue laser are combined by the partitioned film.

[0011] According to one embodiment of this application, the beam combining structure further includes a first reflector, which is used to reflect the red light output by the first red laser to the polarizing beam combiner; the first laser component and the second laser component are respectively located on both sides of the beam combining structure, and the first reflector, the polarizing beam combiner, the red-transmitting and blue-green-reflecting mirror, and the partitioned diaphragm are arranged side by side in sequence.

[0012] According to one embodiment of this application, the center of the first reflector, the center of the polarizing beam combiner, the center of the red-transmitting and blue-green-reflecting mirror, and the center of the partitioned diaphragm are all located on the first axis.

[0013] According to one embodiment of this application, the first reflector, the polarizing beam combiner, the red-transmitting and blue-green-reflecting mirror, and the partitioned membrane all form a 45-degree angle with the first axis; the first reflector and the polarizing beam combiner are perpendicular, the polarizing beam combiner and the red-transmitting and blue-green-reflecting mirror are perpendicular, and the red-transmitting and blue-green-reflecting mirror and the partitioned membrane are perpendicular.

[0014] According to one embodiment of this application, the first region is covered with a green-reflecting and blue-transmitting film, which is configured to reflect green light and transmit blue light; the second region is covered with a blue-reflecting and green-transmitting film, which is configured to reflect blue light and transmit green light; the beam combining structure further includes a red-transmitting and blue-green-reflecting mirror, which is configured to transmit red light and reflect blue and green light, and the beam combining light from the polarizing beam combiner and the beam combining light from the partitioned film are combined by the red-transmitting and blue-green-reflecting mirror.

[0015] According to one embodiment of this application, the beam combining structure further includes a first reflector and a second reflector. The first reflector is used to reflect the red light output by the first red laser to the polarizing beam combiner, and the second reflector is used to reflect the green light output by the first green laser and the blue light output by the first blue laser to the partitioned diaphragm. The first laser component and the second laser component are located on the same side of the beam combining structure, and the first reflector, the polarizing beam combiner, and the red-transmitting and blue-green-reflecting mirror are arranged side by side in sequence. The partitioned diaphragm is located between the red-transmitting and blue-green-reflecting mirror and the second laser component.

[0016] According to one embodiment of this application, the center of the first reflector, the center of the polarizing beam combiner, and the center of the red-transmitting and blue-green-reflecting mirror are all located on the second axis; the center of the second reflector and the center of the partitioned diaphragm are both located on the third axis; the second axis and the third axis are arranged in parallel and spaced apart, and the first laser component and the second laser component are located on the side of the third axis away from the second axis.

[0017] According to one embodiment of this application, the first reflector, the polarizing beam combiner, and the red-transmitting and blue-green-reflecting mirror all form a 45-degree angle with the second axis; the second reflector and the partitioned diaphragm all form a 45-degree angle with the third axis; any two of the first reflector, the polarizing beam combiner, the red-transmitting and blue-green-reflecting mirror, the second reflector, and the partitioned diaphragm are parallel to each other.

[0018] According to one embodiment of this 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.

[0019] According to one embodiment of this application, the first green laser and the first blue laser are directly connected, and the second green laser and the second blue laser are directly connected; the first red laser is spaced apart from the first green laser and the first blue laser, and the second red laser is spaced apart from the second green laser and the second blue laser.

[0020] According to one embodiment of this application, the first red laser, the first green laser, and the first blue laser are arranged side by side in a direction perpendicular to the axis of the first red laser, and the directions of the light output by the three are the same; the second red laser, the second green laser, and the second blue laser are arranged side by side in a direction perpendicular to the axis of the second red laser, and the directions of the light output by the three are the same.

[0021] According to one embodiment of this application, the first region and the second region are located on opposite sides of the centerline of the partitioned membrane.

[0022] This application also provides a projector, which includes the laser beam combining device described in the above embodiments.

[0023] The laser beam combining device and projector provided in this application, by setting a first region and a second region connected on a partitioned membrane, enable the blue and green light output from the first laser component and the second laser component to be combined on the same partitioned membrane, greatly reducing the optical spread of the combined light. Reducing the optical spread helps to reduce the size of the optical system and improve the efficiency of the optical system.

[0024] [Attached Image Description]

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 is a schematic diagram of the structure of a laser beam combining device in the prior art;

[0027] Figure 2 is a structural schematic diagram of an embodiment of the laser beam combining device of this application;

[0028] Figure 3 is a schematic diagram of another embodiment of the laser beam combining device of this application;

[0029] Figure 4 is a schematic diagram of the partitioned diaphragm structure of the laser beam combining device shown in Figure 2;

[0030] Figure 5 is a structural schematic diagram of another embodiment of the laser beam combining device of this application;

[0031] Figure 6 is a structural schematic diagram of an embodiment of the projector of this application.

[0032]

Detailed Implementation Methods

[0033] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be particularly noted that the following embodiments are for illustrative purposes only and do not limit the scope of the application. Similarly, the following embodiments are only some, not all, embodiments of the present application, and all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of the present application.

[0034] The terms "first," "second," and "third" used in the embodiments of this application are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified. All directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationships and movement of components in a specific posture (as shown in the figures). If the specific posture changes, the directional indication will also change accordingly. The terms "comprising" and "having," and any variations thereof, in the embodiments of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or components inherent to these processes, methods, products, or devices.

[0035] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0036] Laser beam combining is a process of coupling multiple laser units into a single beam. In existing technologies, as shown in Figure 1, the light output from the third laser component 100 and the fourth laser component 200 of the laser beam combining device is combined by two beam combiners 300. The combined beam is output through spatial stacking, resulting in an optical spread of more than twice that of a single laser component. The spatial distribution of the beam spot (cross-sectional area) is 7.6mm*8mm. As the beam spot increases, the focal length of the lenses in the optical system also needs to increase accordingly, causing the overall optical system to grow larger with the increase in the optical spread of the combined beam. This necessitates adjustments to the optical system to accommodate the increased beam spot size, affecting the system's efficiency. Optical spread is an important concept in non-imaging optics, used to describe the geometric characteristics of a beam with a specific aperture angle and cross-sectional area.

[0037] This application provides a laser beam combining device, as shown in Figures 2 and 4. The laser beam combining device includes a first laser component 10, a second laser component 20, and a beam combining structure 30. The first laser component 10 includes a first green laser 110 and a first blue laser 120; the second laser component 20 includes a second green laser 210 and a second blue laser 220; the beam combining structure 30 is used to combine the light output from the first laser component 10 and the light output from the second laser component 20. The beam combining structure 30 includes a partitioned diaphragm 310, which includes a first region 311 and a second region 312 connected to each other. The blue light output from the first blue laser 120 and the green light output from the second green laser 210 are combined through the first region 311, and the green light output from the first green laser 110 and the blue light output from the second blue laser 220 are combined through the second region 312. The partitioned diaphragm 310 of this application, by setting a first region 311 and a second region 312 connected to each other, allows the blue light output by the first blue laser 120 and the green light output by the second green laser 210, as well as the green light output by the first green laser 110 and the blue light output by the second blue laser 220, to be combined on a single partitioned diaphragm 310. This greatly reduces the optical spread of the combined light, which is beneficial for reducing the size of the optical system and improving the efficiency of the optical system.

[0038] 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. Co-packaging is a technology that assembles multiple components together in the same package. Using co-packaging technology can reduce the size of laser components, simplify design, and improve reliability. In some embodiments, the co-packaging of the first green laser 110 and the first blue laser 120 indicates that the first green laser 110 and the first blue laser 120 are directly connected, and the co-packaging of the second green laser 210 and the second blue laser 220 indicates that the second green laser 210 and the second blue laser 220 are directly connected.

[0039] In some embodiments, as shown in FIG3, the first laser component 10 further includes a first red laser 130, and the second laser component 20 further includes 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 a single first laser component 10, and the second red laser 230, the second green laser 210, and the second blue laser 220 are integrated into a single second laser component 20.

[0040] In some embodiments, the first red laser 130 is spaced apart from the co-packaged first green laser 110 and first blue laser 120, and the second red laser 230 is spaced apart from the co-packaged second green laser 210 and second blue laser 220. Since the wavelength range of blue and green lasers is between 450-570 nanometers, while the wavelength of red light is approximately 630-750 nanometers, this wavelength difference leads to different propagation characteristics in optical systems. Furthermore, red light is more temperature-sensitive, making it difficult to achieve good coupling and focusing within the same package. Therefore, red lasers are generally not co-packaged with blue and green lasers.

[0041] In some embodiments, the lasers of the first laser assembly 10 and the second laser assembly 20 may be semiconductor lasers. In other embodiments, the lasers of the first laser assembly 10 and the second laser assembly 20 may also be other types of lasers such as solid-state lasers or gas lasers.

[0042] In some embodiments, a first red laser 130, a first green laser 110, and a first blue laser 120 are arranged side-by-side in a direction perpendicular to the axis of the first red laser 130, and the directions of their output light are the same; a second red laser 230, a second green laser 210, and a second blue laser 220 are arranged side-by-side in a direction perpendicular to the axis of the second red laser 230, and the directions of their output light are the same. Here, the axis of the first red laser 130 refers to the direction of its output light, and the axis of the second red laser 230 refers to the direction of its output light.

[0043] In some embodiments, the first laser component 10 and the second laser component 20 are located on opposite sides of the beam combining structure 30. The light output by the first laser component 10 and the light output by the second laser component 20 are in opposite directions. The space between the first red laser 130 and the first green laser 110 corresponds to the position of the second red laser 230. The space between the second red laser 230 and the second green laser 210 corresponds to the position of the fixedly connected first green laser 110 and first blue laser 120.

[0044] In some embodiments, the beam combining structure 30 further includes a half-wave plate 320 and a polarizing beam combiner 330. The half-wave plate 320 is located between the polarizing 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 through the half-wave plate 320 to form S-polarized light. The polarizing beam combiner 330 is configured to reflect S-polarized light and transmit P-polarized light. 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 polarizing beam combiner 330.

[0045] 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 through the half-wave plate 320 to form P-polarized light. The polarization combiner 330 is configured to reflect the P-polarized light and transmit the S-polarized light. 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 combiner 330.

[0046] The first laser component 10 and the second laser component 20 can be the same laser component, outputting red light with the same polarization state. Red light with the same polarization state is prone to interference when combined, leading to laser speckle. This application uses a half-wave plate 320 to convert the P-polarized light output from the second red laser 230 into S-polarized light. Since the S-polarized light and P-polarized light are orthogonally polarized, interference of coherent light can be effectively reduced, thereby reducing speckle formation. The optical spread of the combined red light is nearly half that of existing solutions, and the P-polarized and S-polarized red light each account for half of the total beam.

[0047] Specifically, the polarizing beam combiner 330 can reflect S-polarized light and transmit P-polarized light. The polarizing beam combiner 330 can be a polarizing beam combining prism or a thin-film polarizing beam splitter. The red light output from the second red laser 230 can pass through the half-wave plate 320 and be reflected by the polarizing beam combiner 330, while the red light output from the first red laser 130 can pass through the polarizing beam combiner 330, thereby achieving the combination of P-polarized light and S-polarized light.

[0048] In some embodiments, the beam combining structure 30 further includes a red-transmitting and blue-green-reflecting mirror 340, which is configured to transmit red light and reflect blue and green light. The beam combining light from the polarizing beam combiner 330, the green light output from the first green laser 110, and the blue light output from the first blue laser 120 are combined by the red-transmitting and blue-green-reflecting mirror 340.

[0049] Specifically, the red-transmitting and blue-green-reflecting mirror 340 can be an optical lens coated with a red-transmitting and blue-green-reflecting film. The combined light from the polarizing beam combiner 330 is red light, which can pass through the red-transmitting and blue-green-reflecting mirror 340. The green light output from the first green laser 110 and the blue light output from the first blue laser 120 can be reflected by the red-transmitting and blue-green-reflecting mirror 340.

[0050] In some embodiments, the first region 311 of the partitioned membrane 310 is covered with a green-reflecting, red-transmitting, and blue-transmitting film, which is configured to reflect green light and transmit red and blue light, and the second region 312 is covered with a blue-reflecting, red-transmitting, and green-reflecting film, which is configured to reflect blue light and transmit red and green light.

[0051] Specifically, the partitioned film 310 can be formed by optical coating on a glass substrate. Optical coating refers to the process of depositing one (or more) thin films of metal (or dielectric) onto the surface of optical components. The purpose of coating the surface of optical components is to achieve requirements such as reducing or increasing light reflection, beam splitting, color separation, filtering, and polarization. Commonly used coating methods include vacuum coating (a type of physical coating) and chemical coating. The coating materials for optical coatings can be metal oxides, such as silicon dioxide (SiO2), aluminum oxide (Al2O3), or titanium oxide (TiO2), or metal fluorides, such as magnesium fluoride (MgF2) or calcium fluoride (CaF2), or metals such as gold (Au), silver (Ag), and aluminum (Al).

[0052] In some embodiments, the method for forming the first region 311 and the second region 312 by the partitioned film 310 may be as follows: firstly, the first region 311 is covered by screen printing protective ink on one side of a glass substrate; then, a region coating is performed on the other side of the glass substrate (excluding the first region 311, i.e., the second region 312); after the coating is completed, the second region 312 is required to meet the corresponding optical requirements; then, the first region 311 is cleaned and the protective ink is removed; then, the second region 312 is covered by screen printing protective ink; a region coating is performed on the first region 311 on one side of the glass substrate; after the coating is completed, the second region 312 is cleaned and the protective ink is removed, so that different regions of the same glass substrate have different optical characteristics.

[0053] In some embodiments, the combined light from the red-transmitting and blue-green-reflecting mirror 340, the green light output from the second green laser 210, and the blue light output from the second blue laser 220 are combined by the partitioned diaphragm 310.

[0054] Specifically, the blue light output by the first blue laser 120 can be reflected by the red-transmitting and 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 and 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 through the red-transmitting and blue-green-reflecting mirror 340 can be transmitted through the partitioned diaphragm 310. Finally, the three-color lasers of the first laser component 10 and the second laser component 20 are combined through the partitioned diaphragm 310.

[0055] In some embodiments, the red light transmitted through the red-transmitting and blue-green-reflecting mirror 340 can pass through the middle of the partitioned membrane 310. The first region 311 and the second region 312 of the partitioned membrane 310 need to be tightly connected to avoid gaps in the connection affecting the transmission of red light.

[0056] In some embodiments, the partitioned membrane 310 can be divided in half into a first region 311 and a second region 312, and the areas of the first region 311 and the second region 312 can be the same. Here, dividing in half means dividing the partitioned membrane 310 into two equal parts, the first region 311 and the second region 312, along the midline.

[0057] In some embodiments, the beam combining structure 30 further includes a first reflector 350, which is used to reflect the red light output by the first red laser 130 to the polarizing beam combiner 330.

[0058] In some embodiments, the first reflecting mirror 350, the polarizing beam combiner 330, the red-transmitting and blue-green-reflecting mirror 340, and the partitioning diaphragm 310 are arranged side by side in sequence.

[0059] In some embodiments, the centers of the first reflector 350, the polarizing beam combiner 330, the red-transmitting and blue-green-reflecting mirror 340, and the partitioned diaphragm 310 are all located on the first axis 301 to reduce the volume of the beam combining structure 30. The lasers of the first laser assembly 10 and the second laser assembly 20 are respectively arranged side by side on both sides of the first axis 301 to reduce the volume of the laser beam combining device.

[0060] 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.

[0061] 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.

[0062] In some embodiments, as shown in FIG5, 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 a direction perpendicular to the axis of the first red laser 130, and the directions of the light output by the above lasers are the same.

[0063] In some embodiments, the first region 311 of the partitioned membrane 310 is covered with a green-reflecting and blue-transmitting film, which is configured to reflect green light and transmit blue light, and the second region 312 is covered with a blue-reflecting and green-transmitting film, which is configured to reflect blue light and transmit green light.

[0064] In some embodiments, the combined light from the polarizing combiner 330 and the combined light from the partitioned diaphragm 310 are combined by the red-transmitting and blue-green-reflecting mirror 340.

[0065] Specifically, the blue light output by the first blue laser 120 can be reflected by the first region 311 to the red-transmitting and blue-green-reflecting mirror 340, and then reflected by the red-transmitting and blue-green-reflecting mirror 340; the green light output by the first green laser 110 can be reflected by the second region 312 to the red-transmitting and blue-green-reflecting mirror 340, and then reflected by the red-transmitting and blue-green-reflecting mirror 340; the green light output by the second green laser 210 can be transmitted through the first region 311 to the red-transmitting and blue-green-reflecting mirror 340, and then reflected by the red-transmitting and blue-green-reflecting mirror 340; the blue light output by the second blue laser 220 can be transmitted through the second region 312 to the red-transmitting and blue-green-reflecting mirror 340, and then reflected by the red-transmitting and blue-green-reflecting mirror 340; finally, the red-transmitting and blue-green-reflecting mirror 340 achieves the beam combining of the three-color lasers of the first laser component 10 and the second laser component 20.

[0066] In some embodiments, the beam combining structure 30 further includes a first reflector 350 and a second reflector 360. The first reflector 350 is used to reflect the red light output by the first red laser 130 to the polarizing beam combiner 330, and the second reflector 360 is used to reflect the green light output by the first green laser 110 and the blue light output by the first blue laser 120 to the partitioned diaphragm 310.

[0067] In some embodiments, the first reflector 350, the polarizing beam combiner 330, and the red-transmitting and blue-green-reflecting mirror 340 are arranged side by side, and the second reflector 360 and the partitioning diaphragm 310 are arranged side by side.

[0068] In some embodiments, the centers of the first reflector 350, the polarizing beam combiner 330, and the red-transmitting blue-green mirror 340 are all located on the second axis 302, and the centers of the second reflector 360 and the partitioned diaphragm 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. The first laser component 10 and the second laser component 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.

[0069] Specifically, the angles between the first reflecting mirror 350, the polarizing beam combiner 330, the red-transmitting and blue-green-reflecting mirror 340 and the second axis 302 can all be 45 degrees, and the angles between the second reflecting mirror 360 and the partitioning diaphragm 310 and the third axis 303 can all be 45 degrees. Furthermore, any two of the first reflecting mirror 350, the polarizing beam combiner 330, the red-transmitting and blue-green-reflecting mirror 340, the second reflecting mirror 360, and the partitioning diaphragm 310 are parallel to each other. The first blue laser 120 and the first green laser 110 are co-packaged on the side of the second reflector 360 away from the second axis 302. The first red laser 130 and the first reflector 350 are oppositely disposed on both sides of the third axis 303. The second red laser 230 and the polarizing beam combiner 330 are oppositely disposed on both sides of the third axis 303. The half-wave plate 320 is disposed between the second red laser 230 and the polarizing beam combiner 330. The second green laser 210 and the second blue laser 220 are co-packaged on the side of the partitioned diaphragm 310 away from the red-transmitting and blue-green-reflecting mirror 340.

[0070] The blue light output from the first blue laser 120 is incident at a 45-degree angle on the second reflecting mirror 360, and is reflected sequentially by the second reflecting mirror 360, the first region 311, and the red-transmitting blue-green mirror 340; the green light output from the first green laser 110 is incident at a 45-degree angle on the second reflecting mirror 360, and is reflected sequentially by the second reflecting mirror 360, the second region 312, and the red-transmitting blue-green mirror 340; 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 reflected sequentially by the first reflecting mirror 350 and transmitted through the polarizing beam combiner 330. The first region 10 and the second region 20 are connected by a red-transmitting, blue-reflecting, and green-reflecting mirror 340. The red light output from the second red laser 230 is transmitted through a half-wave plate 320, incident at a 45-degree angle on a polarizing beam combiner 330, reflected by the polarizing beam combiner 330, and then transmitted through the red-transmitting, blue-reflecting, and green-reflecting mirror 340. The green light output from the second green laser 210 is incident at a 45-degree angle on a first region 311, transmitted through the first region 311, and reflected by the red-transmitting, blue-reflecting, and green-reflecting mirror 340. The blue light output from the second blue laser 220 is incident at a 45-degree angle on a second region 312, transmitted through the second region 312, and then reflected by the red-transmitting, blue-reflecting, and green-reflecting mirror 340. Through this optical path design, the light output from the first laser component 10 and the second laser component 20 is converged to the red-transmitting, blue-reflecting, and green-reflecting mirror 340, effectively reducing the optical spread of the combined beam formed by the red-transmitting, blue-reflecting, and green-reflecting mirror 340.

[0071] With the laser beam combining device described above, the spatial distribution of the beam spot formed by the red, green and blue light of the first laser component 10 and the second laser component 20 is 7mm*3.2mm, and the optical spread is reduced to 36.8% of that of the existing scheme.

[0072] This application also provides a projector, as shown in FIG6, which includes the laser beam combining device in the above embodiments.

[0073] In some embodiments, the projector further includes a housing 40, a speckle suppression system, a beam homogenizer, an optical valve, an imaging system, and a laser beam combiner housed within the housing 40. The combined beam emitted by the laser beam combiner is effectively suppressed by the speckle suppression system, homogenized by the beam homogenizer, and projected onto the optical valve. After transmission or reflection through the optical valve, the imaging system magnifies the light emitted by the optical valve to form a projected image.

[0074] The laser beam combining device and projector provided in this application, by setting a first region 311 and a second region 312 connected on the partitioned diaphragm 310, enable the green and blue light output by the first laser component 10 and the second laser component 20 to be combined on the same partitioned diaphragm. By setting a half-wave plate 320 and a polarizing beam combiner 330, the optical spread of the combined light formed by the red light of the first red laser 130 and the red light of the second red laser 230 is reduced by nearly half, and laser speckle can be effectively suppressed. By designing the optical path, the optical spread of the combined light after being combined by the laser beam combining device is greatly reduced, which is beneficial to improving the quality of the combined light, reducing the size of the optical system, and improving the efficiency of the optical system.

[0075] The above description is only a part of the embodiments of this application and does not limit the scope of protection of this application. Any equivalent device or equivalent process transformation made based on the content of this application specification and drawings, or direct or indirect application in other related technical fields, are similarly included in the patent protection scope of this application.

Claims

1. A laser beam combining device, characterized in that, include: A first laser assembly, comprising a first green laser and a first blue laser; The second laser assembly includes a second green laser and a second blue laser. A beam combining structure is provided, wherein the beam combining structure is used to combine the light output from the first laser component and the light output from the second laser component; wherein... The beam combining structure includes a partitioned diaphragm, which includes a first region and a second region connected to each other. The blue light output from the first blue laser and the green light output from the second green laser are combined through the first region, and the green light output from the first green laser and the blue light output from the second blue laser are combined through the second region.

2. The laser beam combining device according to claim 1, characterized in that, The beam combining structure further includes a half-wave plate and a polarizing beam combiner. The first laser component further includes a first red laser, and the second laser component further includes a second red laser. The half-wave plate is located between the polarizing beam combiner and the second red laser. The red light output by both the first and second red lasers is P-polarized. The P-polarized light output by the second red laser is transmitted through the half-wave plate to form S-polarized light. The polarization combiner is configured to reflect the S-polarized light and transmit the P-polarized light. The P-polarized light output by the first red laser and the S-polarized light transmitted through the half-wave plate are combined by the polarization combiner. 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 combining mirror is configured to reflect P-polarized light and transmit S-polarized light. The S-polarized light output by the first red laser and the P-polarized light transmitted through the half-wave plate are combined by the polarization combining mirror.

3. The laser beam combining device according to claim 2, characterized in that, The first region is covered with a green-reflecting, red-transmitting, and blue-transmitting film, which is configured to reflect green light and transmit red and blue light; the second region is covered with a blue-reflecting, red-transmitting, and green-transmitting film, which is configured to reflect blue light and transmit red and green light; the beam combining structure further includes a red-transmitting, blue-reflecting, and green-transmitting mirror, which is configured to transmit red light and reflect blue and green light; the beam combined by the polarizing beam combiner, the green light output from the first green laser, and the blue light output from the first blue laser are combined by the red-transmitting, blue-reflecting, and green-transmitting mirror; the beam combined by the red-transmitting, blue-reflecting, and green-transmitting mirror, the green light output from the second green laser, and the blue light output from the second blue laser are combined by the partitioned film.

4. The laser beam combining device according to claim 3, characterized in that, The beam combining structure further includes a first reflector, which is used to reflect the red light output by the first red laser to the polarizing beam combiner; the first laser component and the second laser component are respectively located on both sides of the beam combining structure, and the first reflector, the polarizing beam combiner, the red-transmitting and blue-green-reflecting mirror, and the partitioned diaphragm are arranged side by side in sequence.

5. The laser beam combining device according to claim 4, characterized in that, The center of the first reflector, the center of the polarizing beam combiner, the center of the red-transmitting and blue-green-reflecting mirror, and the center of the partitioned diaphragm are all located on the first axis.

6. The laser beam combining device according to claim 5, characterized in that, The first reflector, the polarizing beam combiner, the red-transmitting and blue-green-reflecting mirror, and the partitioned membrane all form a 45-degree angle with the first axis; the first reflector and the polarizing beam combiner are perpendicular, the polarizing beam combiner and the red-transmitting and blue-green-reflecting mirror are perpendicular, and the red-transmitting and blue-green-reflecting mirror and the partitioned membrane are perpendicular.

7. The laser beam combining device according to claim 2, characterized in that, The first region is covered with a green-reflecting and blue-transmitting film, which is configured to reflect green light and transmit blue light; the second region is covered with a blue-reflecting and green-transmitting film, which is configured to reflect blue light and transmit green light; the beam combining structure further includes a red-transmitting and blue-green-reflecting mirror, which is configured to transmit red light and reflect blue and green light, and the beam combined by the polarizing beam combiner and the beam combined by the partitioned film are combined by the red-transmitting and blue-green-reflecting mirror.

8. The laser beam combining device according to claim 7, characterized in that, The beam combining structure further includes a first reflector and a second reflector. The first reflector is used to reflect the red light output by the first red laser to the polarizing beam combiner, and the second reflector is used to reflect the green light output by the first green laser and the blue light output by the first blue laser to the partitioned diaphragm. The first laser component and the second laser component are located on the same side of the beam combining structure. The first reflector, the polarizing beam combiner, and the red-transmitting and blue-green-reflecting mirror are arranged side by side in sequence, and the partitioned diaphragm is located between the red-transmitting and blue-green-reflecting mirror and the second laser component.

9. The laser beam combining device according to claim 8, characterized in that, The center of the first reflector, the center of the polarizing beam combiner, and the center of the red-transmitting and blue-green-reflecting mirror are all located on the second axis; the center of the second reflector and the center of the partitioned diaphragm are both located on the third axis; the second axis and the third axis are arranged in parallel and spaced apart, and the first laser component and the second laser component are located on the side of the third axis away from the second axis.

10. The laser beam combining device according to claim 9, characterized in that, The first reflector, the polarizing beam combiner, and the red-transmitting and blue-green-reflecting mirror all form a 45-degree angle with the second axis; the second reflector and the partitioned diaphragm all form a 45-degree angle with the third axis; any two of the first reflector, the polarizing beam combiner, the red-transmitting and blue-green-reflecting mirror, the second reflector, and the partitioned diaphragm are parallel to each other.

11. The laser beam combining device according to claim 1, characterized in that, 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.

12. The laser beam combining device according to claim 2, characterized in that, The first green laser and the first blue laser are directly connected, and the second green laser and the second blue laser are directly connected; the first red laser is spaced apart from the first green laser and the first blue laser, and the second red laser is spaced apart from the second green laser and the second blue laser.

13. The laser beam combining device according to claim 2, characterized in that, The first red laser, the first green laser, and the first blue laser are arranged side by side in a direction perpendicular to the axis of the first red laser, and the direction of the light output by the three lasers is the same; the second red laser, the second green laser, and the second blue laser are arranged side by side in a direction perpendicular to the axis of the second red laser, and the direction of the light output by the three lasers is the same.

14. The laser beam combining device according to claim 1, characterized in that, The first region and the second region are located on opposite sides of the centerline of the partitioned membrane.

15. A projector, characterized in that, Includes the laser beam combining device according to any one of claims 1-14.

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