CN113625523B

CN113625523B - Laser device and laser projection system

Info

Publication number: CN113625523B
Application number: CN202110949509.0A
Authority: CN
Inventors: 颜珂
Original assignee: Qingdao Hisense Laser Display Co Ltd
Current assignee: Qingdao Hisense Laser Display Co Ltd
Priority date: 2021-08-18
Filing date: 2021-08-18
Publication date: 2022-11-04
Anticipated expiration: 2041-08-18
Also published as: CN113625523A

Abstract

The invention discloses a laser and a laser projection system. The diffractive optical element shapes the laser beam emitted by the laser chip component, so that the laser beam emitted by the laser can be shaped and homogenized according to actual needs, components such as a light guide pipe and a diffusion sheet do not need to be arranged in the projection system, energy loss caused by the light guide pipe is avoided, the structural design of the projection system is effectively simplified, and the miniaturization design is favorably realized.

Description

Laser device and laser projection system

Technical Field

The invention relates to the technical field of projection display, in particular to a laser and a laser projection system.

Background

The laser projection display technology is also called a laser projection technology or a laser display technology, and is a technology for performing projection display using laser light as a light source. The laser projection can truly reproduce rich and bright colors of an objective world and provide more shocking expressive force. The color gamut coverage rate of the display screen can reach more than 90% of the color space which can be identified by human eyes, and is more than twice of the traditional display color gamut coverage rate.

At present, a laser projection system usually has an illumination system disposed on the light-emitting side of a laser light source for shaping and homogenizing. The illumination system is usually realized by using a light guide, but a lot of energy loss occurs when the light emitted from the laser light source is irradiated into a narrow light guide. To achieve a certain uniformity, the light guide needs to be made longer, usually more than 30mm, thus resulting in a long length of the whole optical engine and not realizing a smaller volume.

Disclosure of Invention

In some embodiments of the invention, a laser includes a plurality of laser chip assemblies, and a diffractive optical element positioned on an exit side of the laser chip assemblies. The diffractive optical element shapes the laser beam emitted by the laser chip component, so that the laser beam emitted by the laser can be shaped and homogenized according to actual needs, components such as a light guide pipe and a diffusion sheet do not need to be arranged in the projection system, energy loss caused by the light guide pipe is avoided, the structural design of the projection system is effectively simplified, and the miniaturization design is favorably realized.

In some embodiments of the present invention, the diffractive optical element includes a plurality of diffractive units, each of which is distributed in a two-dimensional matrix. Wherein, the diffraction unit is a step-shaped structure formed by a plurality of layers of microstructures, and the size of one layer of microstructure is 10 nm-100 μm. The diffraction optical element adopts a micro-nano etching process to form diffraction units which are distributed in two dimensions, each diffraction unit can have specific appearance, size, refractive index and the like, and the laser wave front phase distribution can be finely regulated and controlled. The laser beam is diffracted after passing through each diffraction unit, and generates interference at a certain distance to form specific light intensity distribution.

In some embodiments of the invention, laser spots emitted by the laser chip assembly are shaped into rectangular spots with uniform intensity distribution and set size after passing through the diffractive optical element, so that the illumination requirement in the projection system is met.

In some embodiments of the present invention, the laser further includes a case, the laser chip assembly and the reflector located at the light exit side of the laser chip assembly are disposed in the case, and the diffractive optical element is located at the light exit side of the reflector. The light emitting position can be adjusted by adjusting the reflector through the mode that the reflector reflects the light emitted by the laser chip component, so that higher precision is achieved.

In some embodiments of the invention, the laser chip assembly comprises a red laser chip assembly, a green laser chip assembly and a blue laser chip assembly. Accordingly, the diffractive optical element includes a first diffractive optical element, a second diffractive optical element, and a third diffractive optical element. The first diffractive optical element is positioned on the light-emitting side of the red laser chip component and is used for shaping the red laser beam; the second diffractive optical element is positioned on the light-emitting side of the green laser chip component and is used for shaping the green laser beam; and the third diffractive optical element is positioned on the light-emitting side of the blue laser chip component and is used for shaping the blue laser beam. Therefore, laser beams with different colors are shaped into rectangular light spots with uniform energy distribution.

In some embodiments of the invention, the laser further comprises a sealing glass forming a hermetic seal with the package. The diffractive optical element is located on the side of the sealing glass facing away from the laser chip assembly. Therefore, the packaging structure of the laser does not need to be changed, and the diffraction optical element is arranged after the laser is packaged.

In some embodiments of the invention, the diffractive optical element is disposed on a side of the sealing glass facing the laser chip assembly. The diffractive optical element is packaged in the laser, so that the protective effect on the diffractive optical element can be achieved, the service life of the diffractive optical element can be prolonged, and the intensity distribution of the emergent laser beams of the laser is uniform.

In some embodiments of the invention, the diffractive optical element is located on a side of the annular side wall of the envelope facing away from the base, the diffractive optical element forming an enclosed space with the envelope. The diffraction optical element is adopted to replace sealing glass, so that the diffraction element and the tube shell form a sealing structure, and the laser chip assembly is packaged, thereby simplifying the structural design.

In some embodiments of the present invention, a fresnel structure is disposed on a surface of the diffractive optical element on a side facing the laser chip assembly, and a plurality of diffractive elements are formed on a surface of the diffractive optical element on a side facing away from the laser chip assembly. The Fresnel structure is used for collimating emergent light of the laser chip assembly; the diffraction unit is used for shaping the incident laser beam. Thereby omitting the collimating lens and making the structure of the laser more compact.

In some embodiments of the present invention, the projection system includes any one of the above lasers, a light combining component located on the light emitting side of the laser, a reflecting component located on the light emitting side of the light combining component, a light valve modulating component located on the reflecting light path of the reflecting component, and a projection lens located on the light emitting side of the light valve modulating component.

In some embodiments of the present invention, the light beam emitted from the laser is a rectangular light spot with uniform intensity distribution, when the intensity distribution and divergence angle of the laser beam emitted from the laser meet the use requirements of the light valve modulation component, the light combining component is directly adopted to simply combine the laser beams with different colors emitted from the laser and then emit the combined laser beam to the reflection component, the reflection component reflects the light to the light valve modulation component at a proper angle, the light is modulated by the light valve modulation component and then emitted to the projection lens, the projection lens forms an image to project the image on the projection screen or a set position, and a viewer can view a display picture by viewing the projection screen.

In some embodiments of the present invention, the projection system includes at least two lasers as described above, the light combining component is located at an intersection of emergent lights of the lasers, and is configured to combine emergent light beams of the lasers, the light emitting side of the light combining component is further provided with the reflection component, the reflection path of the reflection component is provided with the light valve modulation component, and the light emitting side of the light valve modulation component is provided with the projection lens. All be provided with diffractive optical element in above-mentioned arbitrary laser instrument, diffractive optical element carries out the plastic to the laser beam of laser chip subassembly outgoing to can carry out the plastic homogenization with the laser beam of laser instrument outgoing according to actual need, thereby no longer need set up parts such as light pipe, diffusion piece in projection system, avoid because the energy loss that the light pipe caused, effectively simplify projection system's structural design, be favorable to realizing miniaturized design.

In some embodiments of the present invention, the projection system further comprises an illumination lens group positioned between the light combining component and the reflecting component. The illumination lens group is used for shaping and homogenizing the light beam incident to the light valve modulation component, so that the use requirement of the light valve modulation component is met.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments of the present invention will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of a light spot intensity curve provided by an embodiment of the invention;

fig. 2 is a schematic structural diagram of a laser according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a tube housing provided in an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a diffractive optical element according to an embodiment of the present invention;

fig. 5 is one of schematic light spots before and after a laser beam passes through a diffraction element according to an embodiment of the present invention;

fig. 6 is a second schematic diagram of light spots before and after the laser beam passes through the diffraction element according to the embodiment of the present invention;

fig. 7 is a second schematic structural diagram of a laser according to an embodiment of the present invention;

fig. 8 is a third schematic structural diagram of a laser according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of a projection system according to an embodiment of the present invention;

FIG. 10 is a second schematic diagram of a projection system according to an embodiment of the present invention;

fig. 11 is a third schematic structural diagram of a projection system according to an embodiment of the invention.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, the present invention is further described with reference to the accompanying drawings and examples. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus their repetitive description will be omitted. The words expressing the position and direction described in the present invention are illustrated in the accompanying drawings, but may be changed as required and still be within the scope of the present invention. The drawings of the present invention are for illustrative purposes only and do not represent true scale.

The projection display is a method or an apparatus for controlling a light source by plane image information, enlarging and displaying an image on a projection screen using an optical system and a projection space. With the development of projection display technology, projection display is gradually applied to the fields of business activities, conference exhibition, scientific education, military command, traffic management, centralized monitoring, advertising entertainment and the like, and the advantages of large display picture size, clear display and the like are also suitable for the requirement of large-screen display.

A commonly used projection system is a Digital Light Processing (DLP) architecture, and a Digital Micromirror Device (DMD) is used as a core Device, light emitted from a projection Light source is incident on the DMD to generate an image, and then the emergent Light of the image generated by the DMD is incident on a projection lens, and is imaged by the projection lens and finally received by a projection screen.

The projection light source can adopt an MCL laser, and the MCL laser has high integration level and is beneficial to the miniaturization development of the laser light source. The MCL laser generally includes a plurality of laser chips, and may include three laser chips of three tricolor light at the same time, so that the emission of the tricolor light may be realized by using one MCL laser.

Fig. 1 is a schematic diagram of a spot intensity curve according to an embodiment of the present invention.

At present, in full-color laser display, because the light energy emitted by a single laser chip is distributed in a gaussian manner, as shown in fig. 1 (a), the gaussian distribution shows a tendency that the light intensity at the central position is relatively high, and the light intensity at the edge position is reduced sharply, which cannot meet the requirement of uniform illumination.

In order to realize uniform illumination, it is necessary to convert its emergent laser light into a rectangular spot, as shown in fig. 1 (b). The light intensity of the rectangular light spots at each position is uniform, and the illumination requirement in a projection system is met.

In order to homogenize the light intensity of the laser beam, a diffusion sheet may be disposed on the light exit side of the laser to homogenize the beam, but in practice, the diffusion sheet is used to homogenize the beam, and the spot intensity becomes as shown in fig. 1 (c), the center brightness is high, and the edge brightness is low. If the light intensity is to be more uniform, the diffusion angle needs to be increased, which results in a large loss of edge energy.

In addition, in the projection system, it is necessary to provide a light-homogenizing member such as a light guide to homogenize light, but a large amount of energy loss occurs when light emitted from the laser light source is incident on a narrow light guide. To achieve a certain uniformity, the light guide needs to be made longer, usually more than 30mm, thus resulting in a long length of the whole optical engine and not realizing a smaller volume.

In view of this, embodiments of the present invention provide a laser and a projection system, which can effectively homogenize intensity distribution of a laser beam, omit the function of a light guide, and realize a small-volume design of the projection system.

Fig. 2 is a schematic structural diagram of a laser according to an embodiment of the present invention.

As shown in fig. 2, the laser includes: package 100, a plurality of laser chip assemblies 200, a mirror 300, a sealing glass 400, a collimating lens 500, and a diffractive optical element 600.

Fig. 3 is a schematic structural diagram of a tube shell according to an embodiment of the present invention.

As shown in fig. 3, the package 100 is used for accommodating the laser chip assembly 200 and packaging the laser chip assembly 200. The case 100 includes a bottom plate 101 and a ring-shaped sidewall 102 above the bottom plate, and the bottom plate 101 and the ring-shaped sidewall 102 form an accommodating space. The bottom plate 101 and the annular sidewall 102 may be made of the same material, for example, a material such as oxygen-free copper or a metal. The bottom plate 101 and the annular sidewall 102 may be fabricated separately and then welded to form an accommodating space.

A plurality of laser chip assemblies 200 are fixed to the bottom plate 101 of the package. The laser chip assembly 200 includes a laser chip 201 and a heat sink 202. The laser Chip 201 and the heat sink 202 are soldered by a high-precision eutectic soldering machine to form a laser Chip assembly, which is also called a Cos (Chip on subassembly, cos for short). The heat sink 202 is used for dissipating heat of the laser chip 201, and may be made of a metal material, which is not limited herein.

As shown in fig. 2 and 3, a plurality of mirrors 300 are located within the envelope 100. One reflector 300 corresponds to at least one laser chip assembly 200, and the reflector 300 is located at the light-emitting side of the corresponding laser chip assembly 200 and is used for receiving the light emitted from the corresponding laser chip assembly 200 and reflecting the light towards a set direction.

The reflector 300 is used for deflecting the outgoing light of the laser chip assembly 200, and an angle between a reflection surface of the reflector 300 and the outgoing direction of the laser chip assembly 200 may be 45 ° in general. The embodiment of the invention adopts the light path design, and the light emitting position can be adjusted by adjusting the reflector 300 in the form of reflecting the light emitted by the laser chip component 200 through the reflector 300, so that higher precision is achieved.

The laser also comprises a cover plate which is not shown in the figure, and a metal frame is arranged around the cover plate and used for welding with the tube shell, and particularly the cover plate can be welded on the tube shell by using a parallel seal welding technology. In which the sealing glass 400 is fixed on the cover plate by a green paste.

The collimating lens 500 is located on a side of the sealing glass 400 away from the package 100, and in specific implementation, the collimating lens 500 may be an aspheric lens, and the aspheric collimating lens 500 is adjusted in collimation by controlling an alignment process, and is fixed on the cover plate by a UV glue.

The laser beam emitted by the laser chip assembly 200 is gaussian distributed, so that the requirement of uniform intensity distribution required by a projection system is not met. In view of this, the embodiment of the present invention further provides the diffractive optical element 600 on the light-emitting side of the laser chip assembly 200, and specifically, the diffractive optical element 600 may be disposed on the light-emitting side of the reflector 300. The diffractive optical element can shape the laser beam emitted by the laser chip component 200, so that the energy distribution of the shaped laser beam is uniform, the light spots in Gaussian distribution are shaped into rectangular light spots with uniform energy distribution, and the illumination requirement of the projection system is met.

Fig. 4 is a schematic structural diagram of a diffractive optical element according to an embodiment of the present invention.

As shown in fig. 4, specifically, a Diffractive Optical Element (DOE) 600 includes a plurality of diffraction cells 60, and each diffraction cell 60 is distributed in a two-dimensional matrix. Wherein, the diffraction unit 60 is a step-shaped structure composed of a plurality of layers of microstructures, and the size of one layer of microstructures is 10 nm-100 μm.

The DOE (600) is formed by adopting a micro-nano etching process to form diffraction units 60 which are distributed in two dimensions, each diffraction unit 60 can have specific appearance, size, refractive index and the like, and the laser wave front phase distribution can be finely regulated and controlled. The laser beam is diffracted after passing through each diffraction unit 60 and interferes at a certain distance to form a specific light intensity distribution.

Fig. 5 is a schematic diagram of a light spot before and after a laser beam passes through a diffraction element according to an embodiment of the present invention.

As shown in fig. 5, by special design of each diffraction unit in the DOE (600), the laser beam can be made to be a rectangular spot after passing through the DOE (600). The energy distribution of the rectangular light spots is more uniform, and the illumination requirement in the projection system can be met.

Laser beam through set up diffraction optical element in the laser instrument and carry out the plastic to the laser chip subassembly outgoing to can carry out the plastic homogenization with the laser beam of laser instrument outgoing according to actual need, thereby no longer need set up parts such as light pipe, diffusion piece in projection system, avoid because the energy loss that the light pipe caused, effectively simplify projection system's structural design, be favorable to realizing miniaturized design.

As shown in fig. 2, the laser provided by the embodiment of the present invention may adopt an MCL laser. The laser chip assemblies 200 in the laser are arranged in an array. Wherein, the laser chip assembly can comprise a red laser chip assembly 201, a green laser chip assembly 202 and a blue laser chip assembly 203; each red light laser chip component 201 is arranged in an array to form a red light laser chip component array, each green light laser chip component 202 is arranged in an array to form a green light laser chip component array, and each blue light laser chip component 203 is arranged in an array to form a blue light laser chip component array. For example, the red laser chip assemblies 201 may form a 2 × 4 array of red laser chip assemblies, the green laser chip assemblies 202 may form a 1 × 4 array of green laser chip assemblies, and the blue laser chip assemblies 203 may form a 1 × 4 array of blue laser chip assemblies, so that two rows of red laser chip assemblies 201, one row of green laser chip assemblies 202, and one row of blue laser chip assemblies 203 are sequentially arranged to form a 4 × 4 array of laser chip assemblies.

Accordingly, the diffractive optical element 600 may include a first diffractive optical element 6001, a second diffractive optical element 602, and a third diffractive optical element 603; the first diffractive optical element 601 is located on the light-emitting side of the red laser chip module array, the second diffractive optical element 602 is located on the light-emitting side of the green laser chip module array, and the third diffractive optical element 603 is located on the light-emitting side of the blue laser chip module array.

The first diffractive optical element 601 is used for shaping the laser beam emitted by the red laser chip assembly, the second diffractive optical element 602 is used for shaping the laser beam emitted by the green laser chip assembly, and the third diffractive optical element 603 is used for shaping the laser beam emitted by the blue laser chip assembly.

Fig. 6 is a second schematic diagram of a light spot before and after the laser beam passes through the diffraction element according to the embodiment of the present invention.

As shown in fig. 6, the laser beam emitted from the red laser chip assembly 201 is gaussian-distributed spots 201x shown on the left side, the laser beam emitted from the green laser chip assembly 202 is gaussian-distributed spots 202x shown on the left side, and the laser beam emitted from the blue laser chip assembly 203 is gaussian-distributed spots 203x shown on the left side. After the laser beam emitted by the red laser chip assembly 201 is shaped by the first diffractive optical element 601, a rectangular light spot 201y with uniform intensity distribution shown on the right side can be formed; after the laser beam emitted from the green laser chip assembly 202 is shaped by the second diffractive optical element 602, a rectangular spot 202y with uniform intensity distribution as shown on the right side can be formed; after the laser beam emitted from the blue laser chip assembly 203 is shaped by the third diffractive optical element 603, a rectangular spot 203y having a uniform intensity distribution as shown on the right side can be formed. Therefore, the corresponding diffractive optical elements are sequentially arranged on the light emergent side of the laser chip component array of each color, and the emergent laser beams of the laser chip components can be shaped into rectangular light spots with uniform intensity distribution and set sizes. Therefore, emergent light of the laser can meet the illumination requirement of the projection system.

The sizes and the divergence angles of the red light spot, the green light spot and the blue light spot can be different, the red light spot, the green light spot and the blue light spot can be respectively designed according to a specific light combining light path, an illumination light path and the required optical expansion of the projection system, and the parameters of the first diffraction optical unit, the second diffraction optical unit and the third diffraction optical unit can be correspondingly adjusted to meet the requirements of practical application without limitation.

In specific implementation, the laser chip components in the laser may be arranged according to other rules, and at this time, only the parameters of the diffraction unit need to be adjusted according to the requirements of the emitted rectangular light spot, so that the specific diffractive optical element corresponds to the specific diffractive optical element. The embodiment of the invention does not limit the specific arrangement structure of the laser chip components and the specific parameters of the diffractive optical element.

In some embodiments, as shown in fig. 2, the diffractive optical element 600 may be disposed on a side of the sealing glass 400 facing away from the laser chip assembly 200. Therefore, the packaging structure of the laser does not need to be changed, and the diffraction optical element is arranged after the laser is packaged.

Fig. 7 is a second schematic structural diagram of a laser according to an embodiment of the present invention.

As shown in fig. 7, in some embodiments, the diffractive optical element 600 may also be disposed on the side of the sealing glass 400 facing the laser chip assembly 200. The diffractive optical element 600 is packaged in the laser, so that the diffractive optical element 600 can be protected, the service life of the diffractive optical element 600 can be prolonged, and the intensity distribution of the laser beam emitted by the laser is uniform.

Fig. 8 is a third schematic structural diagram of a laser according to an embodiment of the present invention.

In some embodiments, as shown in fig. 8, diffractive optical element 600 is located on the side of the annular sidewall 102 of the cartridge facing away from base 101, diffractive optical element 600 forming an enclosed space with cartridge 100. The laser chip module 200 is packaged using the diffractive optical element 600 instead of the sealing glass so that the diffractive element 600 and the package form a sealed structure, whereby the structural design can be simplified.

In some embodiments, as shown in fig. 8, a fresnel structure f may be further provided on a surface of the diffractive optical element 600 on a side facing the laser chip assembly 200, and a plurality of diffractive units may be formed on a surface of the diffractive optical element 600 on a side facing away from the laser chip assembly 200. The Fresnel structure f is used for collimating emergent light of the laser chip assembly 200; the diffraction unit is used for shaping the incident laser beam.

With the diffractive optical element 600 shown in fig. 8, there is no need to additionally provide a collimating lens, and the fresnel structure f on the side of the diffractive optical element 600 facing the laser chip assembly 200 can act as a collimating lens to collimate the light. Through setting up fresnel structure f and diffraction unit at two surfaces of diffraction optical element, both can carry out the collimation to the light, can carry out the plastic to laser beam again for the structure of laser instrument is compacter.

In another aspect, an embodiment of the invention provides a projection system. Fig. 9 is a schematic structural diagram of a projection system according to an embodiment of the present invention.

As shown in fig. 9, the projection system includes any one of the above lasers 1, a light combining component 2 located on the light emitting side of the laser 1, a reflecting component 3 located on the light emitting side of the light combining component 2, a light valve modulating component 4 located on the reflected light path of the reflecting component 3, and a projection lens 5 located on the light emitting side of the light valve modulating component 4.

The emergent light of the laser provided by the embodiment of the invention is a rectangular light spot with uniform intensity distribution, when the intensity distribution and the divergence angle of the laser beam emitted by the laser meet the use requirements of the light valve modulation part 4, the light combining component 2 can be directly adopted to simply combine the laser beams with different colors emitted by the laser and then emit the laser beams to the reflection component 3, the reflection component 3 reflects the light to the light valve modulation part 4 at a proper angle, the light is modulated by the light valve modulation part 4 and then emitted to the projection lens 5, and the projection lens 5 forms an image so as to project the image on a projection screen or a set position, so that a viewer can view a display picture by viewing the projection screen.

The laser provided by the embodiment of the invention is provided with the diffractive optical element which shapes the laser beam emitted by the laser chip component, so that the laser beam emitted by the laser can be shaped and homogenized according to actual needs, components such as a light guide pipe, a diffusion sheet and the like do not need to be arranged in a projection system, the energy loss caused by the light guide pipe is avoided, the structural design of the projection system is effectively simplified, and the miniaturization design is favorably realized.

Specifically, as shown in fig. 9, when the laser 1 includes a red laser chip assembly, a green laser chip assembly, and a blue laser chip assembly, the light combining assembly 2 may include a reflecting mirror 21, a first light combining mirror 22, and a second light combining mirror 23.

Wherein, the reflector 21 is located at the light-emitting side of the blue laser chip assembly; the first light combining mirror 22 is positioned at the intersection of the emergent light of the reflector 21 and the emergent light of the green laser chip assembly; the second light combining lens 23 is located at the intersection of the emergent light of the first light combining lens 22 and the emergent light of the red laser chip assembly.

The reflector 21 is used for reflecting the blue laser beam emitted by the blue laser chip component to the first light-combining mirror 22; the first light combining mirror 22 is used for transmitting the blue laser beam emitted by the blue laser chip assembly and reflecting the green laser beam emitted by the green laser chip assembly; the second light combining mirror 23 is used for transmitting blue laser beams and green laser beams emitted by the blue laser chip assembly and the green laser chip assembly and reflecting red laser beams emitted by the green laser chip assembly. Thereby combining the red, green and blue laser beams and emitting the combined beam from the second combining mirror 23 side.

The reflection assembly 3 may be disposed on the light exit side of the second combiner 23. The reflecting member 3 may be, for example, a total reflection prism. In general, the reflection assembly 3 may include two total reflection prisms disposed opposite to each other, and when the laser beam is incident to one of the total reflection prisms at a set angle, the incident angle satisfies a total reflection condition of the total reflection prism, and the total reflection prism may reflect all the light toward the light valve modulation component 4. The light is modulated by the light valve modulation part 4 and then emitted to the total reflection prism again, and at the moment, the light can be smoothly emitted without meeting the total reflection condition; and the modulated light can be vertically incident on the projection lens 5 through the refraction effect of another total reflection prism on the light.

In addition, the reflection assembly 4 may also adopt a mirror, and after the laser beam is incident on the mirror at a set angle, the mirror reflects the light to the light valve modulation component 4 in a direction satisfying the incident angle of the light valve modulation component 4. The light valve modulating section 4 modulates light and emits the modulated light to the projection lens.

The light valve modulation part 4 can adopt a DMD (digital micromirror device), the DMD is a reflection-type light valve device, the surface of the DMD comprises thousands of tiny reflectors, each tiny reflector can be independently driven to deflect, and reflected light enters the projection lens 5 by controlling the deflection angle of the DMD, so that light is modulated.

The outgoing light modulated by the light valve modulation component 4 needs to be imaged through the projection lens 5 to project an image on a projection screen or a set position, and a viewer can view a display picture by viewing the projection screen.

Fig. 10 is a second schematic structural diagram of a projection system according to an embodiment of the invention.

As shown in FIG. 10, in some embodiments, the projection system further includes an illumination lens group 6 positioned between the light combining component 2 and the reflective component 3. The illumination lens group 6 is used for shaping and homogenizing the light beam incident to the light valve modulation component 4, so as to meet the use requirement of the light valve modulation component 4.

Fig. 11 is a third schematic structural diagram of a projection system according to an embodiment of the present invention.

As shown in fig. 11, in some embodiments, the projection system may include at least two of the above-mentioned lasers, and in addition, the projection system further includes a light combining assembly 2 located at an emergent light junction of the lasers, where the light combining assembly 2 is configured to combine emergent light beams of the lasers.

For example, as shown in fig. 11, the projection system includes a first laser 1a and a second laser 1b; wherein the first laser 1a and the second laser 1b may be two lasers with the same structure. The first laser 1a and the second laser 1b may each include a red laser chip assembly, a green laser chip assembly, and a blue laser chip assembly. In the two lasers, the arrangement rule of the three laser chip components may be the same.

The laser projection system further includes: and the light combining component 2 is positioned at the intersection of the emergent beams of the first laser 1a and the second laser 1b, and is used for combining the emergent beams of the first laser 1a and the second laser 1 b.

The light combining component 2 may include a first light combining mirror 22 and a second light combining mirror 23. The first beam combiner 22 is used for transmitting the red laser beam and reflecting the green and blue laser beams; the second beam combiner 23 is used for transmitting the green and blue laser beams and reflecting the red laser beam, so as to combine the laser beams with different colors emitted by the two lasers.

Besides, the light beam after the light combination can be directly incident to the reflection assembly 3 so that the light valve modulation component 4 modulates the incident light, or an illumination lens group 6 can be arranged between the light combination assembly 2 and the reflection assembly 3 so as to further shape and homogenize the laser beam.

All be provided with diffractive optical element in above-mentioned arbitrary laser instrument, diffractive optical element carries out the plastic to the laser beam of laser chip subassembly outgoing to can carry out the plastic homogenization with the laser beam of laser instrument outgoing according to actual need, thereby no longer need set up parts such as light pipe, diffusion piece in projection system, avoid because the energy loss that the light pipe caused, effectively simplify projection system's structural design, be favorable to realizing miniaturized design.

According to a first inventive concept, a laser includes a plurality of laser chip assemblies, and a diffractive optical element located at a light exit side of the laser chip assemblies. The diffractive optical element shapes the laser beam of laser chip subassembly outgoing to can carry out the plastic homogenization with the laser beam of laser instrument outgoing according to actual need, thereby no longer need set up parts such as light pipe, diffusion piece in projection system, avoid because the energy loss that the light pipe caused, effectively simplify projection system's structural design, be favorable to realizing miniaturized design.

According to the second inventive concept, the diffractive optical element includes a plurality of diffraction cells, each of which is distributed in a two-dimensional matrix. Wherein, the diffraction unit is a step-shaped structure formed by a plurality of layers of microstructures, and the size of one layer of microstructure is 10 nm-100 μm. The diffraction optical element adopts a micro-nano etching process to form diffraction units which are distributed in two dimensions, each diffraction unit can have specific appearance, size, refractive index and the like, and the laser wave front phase distribution can be finely regulated and controlled. The laser beam is diffracted after passing through each diffraction unit, and generates interference at a certain distance to form specific light intensity distribution.

According to the third inventive concept, the laser spot emitted by the laser chip assembly is shaped into the rectangular spot with uniform intensity distribution and set size after passing through the diffractive optical element, so that the illumination requirement in the projection system is met.

According to a fourth inventive concept, the laser further includes a case, the laser chip assembly and the reflecting mirror located on the light exit side of the laser chip assembly are disposed in the case, and the diffractive optical element is located on the light exit side of the reflecting mirror. The light-emitting position can be adjusted by adjusting the reflector through the light-emitting form of the laser chip component reflected by the reflector, so that higher precision is achieved.

According to a fifth inventive concept, a laser chip assembly includes a red laser chip assembly, a green laser chip assembly, and a blue laser chip assembly. Accordingly, the diffractive optical element includes a first diffractive optical element, a second diffractive optical element, and a third diffractive optical element. The first diffractive optical element is positioned on the light-emitting side of the red laser chip component and is used for shaping the red laser beam; the second diffractive optical element is positioned on the light-emitting side of the green laser chip component and is used for shaping the green laser beam; and the third diffractive optical element is positioned on the light-emitting side of the blue laser chip component and is used for shaping the blue laser beam. Therefore, laser beams with different colors are shaped into rectangular light spots with uniform energy distribution.

According to a sixth inventive concept, the laser further includes a sealing glass forming a sealing structure with the package. The diffractive optical element is located on the side of the sealing glass facing away from the laser chip assembly. Therefore, the packaging structure of the laser does not need to be changed, and the diffraction optical element is arranged after the laser is packaged.

According to the seventh inventive concept, the diffractive optical element is disposed on a side of the sealing glass facing the laser chip assembly. The diffractive optical element is packaged in the laser, so that the protective effect on the diffractive optical element can be achieved, the service life of the diffractive optical element can be prolonged, and the intensity distribution of the emergent laser beams of the laser is uniform.

According to an eighth inventive concept, the diffractive optical element is located on a side of the annular side wall of the tube housing facing away from the base plate, the diffractive optical element forming an enclosed space with the tube housing. The diffraction optical element is adopted to replace sealing glass, so that the diffraction element and the tube shell form a sealing structure, and the laser chip assembly is packaged, thereby simplifying the structural design.

According to the ninth inventive concept, a fresnel structure is provided on a surface of the diffractive optical element on a side facing the laser chip assembly, and a plurality of diffraction cells are formed on a surface of the diffractive optical element on a side facing away from the laser chip assembly. The Fresnel structure is used for collimating emergent light of the laser chip assembly; the diffraction unit is used for shaping the incident laser beam. Thereby omitting the collimating lens and making the structure of the laser more compact.

According to a tenth inventive concept, a projection system includes any one of the above lasers, a light combining component located at a light emitting side of the laser, a reflecting component located at the light emitting side of the light combining component, a light valve modulating component located on a reflecting light path of the reflecting component, and a projection lens located at the light emitting side of the light valve modulating component.

According to the eleventh invention, the light beam emitted from the laser is a rectangular light spot with uniform intensity distribution, when the intensity distribution and divergence angle of the laser beam emitted from the laser meet the use requirements of the light valve modulation component, the light beam with different colors emitted from the laser is simply combined by the light combining component and then is emitted to the reflection component, the reflection component reflects the light to the light valve modulation component at a proper angle, the light is modulated by the light valve modulation component and then is emitted to the projection lens, the projection lens forms an image to project the image on the projection screen or a set position, and a viewer can view a display picture by viewing the projection screen.

According to a twelfth inventive concept, the projection system comprises at least two lasers, the light combining assembly is located at the intersection of the emergent light of the lasers and used for combining the emergent light beams of the lasers, the light emergent side of the light combining assembly is further provided with the reflection assembly, the reflection path of the reflection assembly is provided with the light valve modulation component, and the light emergent side of the light valve modulation component is provided with the projection lens. All be provided with diffractive optical element in above-mentioned arbitrary laser instrument, diffractive optical element carries out the plastic to the laser beam of laser chip subassembly outgoing to can carry out the plastic homogenization with the laser beam of laser instrument outgoing according to actual need, thereby no longer need set up parts such as light pipe, diffusion piece in projection system, avoid because the energy loss that the light pipe caused, effectively simplify projection system's structural design, be favorable to realizing miniaturized design.

According to a thirteenth inventive concept, the projection system further comprises an illumination lens group located between the light combining component and the reflecting component. The illumination lens group is used for shaping and homogenizing the light beam incident to the light valve modulation component, so that the use requirement of the light valve modulation component is met.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A laser, comprising:

a pipe shell; the pipe shell comprises a bottom plate and an annular side wall positioned on the bottom plate, and an accommodating space is formed by the bottom plate and the annular side wall;

the laser chip assemblies are fixed on the bottom plate of the tube shell; and

a diffractive optical element located on a light exit side of the laser chip assembly; the diffraction optical element is used for shaping the laser beam emitted by the laser chip component;

the diffractive optical element is positioned on one side, away from the bottom plate, of the annular side wall of the tube shell to form a closed space with the tube shell, the surface, facing the laser chip assembly, of the diffractive optical element is provided with a Fresnel structure, and the surface, away from the laser chip assembly, of the diffractive optical element is provided with a plurality of diffraction units; the Fresnel structure is used for collimating emergent light of the laser chip assembly; the diffraction unit is used for shaping the incident laser beam.

2. The laser of claim 1, wherein each of said diffraction cells is distributed in a two-dimensional matrix;

the diffraction unit is a stepped structure formed by a plurality of layers of microstructures.

3. The laser of claim 2, wherein a layer of the microstructures has a dimension of 10nm to 100 μm.

4. The laser of claim 1, further comprising:

a plurality of mirrors located within the envelope; one reflector corresponds to at least one laser chip assembly, and the reflector is positioned on the light emergent side of the corresponding laser chip assembly and used for receiving the reflection of the emergent light of the corresponding laser chip assembly to a set direction;

the diffractive optical element is located on a light exit side of the mirror.

5. The laser of any of claims 1-4, wherein the laser chip assembly comprises a red laser chip assembly, a green laser chip assembly, and a blue laser chip assembly; the red laser chip assemblies are arranged in an array to form a red laser chip assembly array, the green laser chip assemblies are arranged in an array to form a green laser chip assembly array, and the blue laser chip assemblies are arranged in an array to form a blue laser chip assembly array;

the diffractive optical element includes a first diffractive optical element, a second diffractive optical element, and a third diffractive optical element; the first diffractive optical element is located on the light-emitting side of the red light laser chip component array, the second diffractive optical element is located on the light-emitting side of the green light laser chip component array, and the third diffractive optical element is located on the light-emitting side of the blue light laser chip component array.

6. A laser projection system, comprising at least one laser according to any one of claims 1 to 5, a light combining component located at the light emitting side of the laser, a reflecting component located at the light emitting side of the light combining component, a light valve modulating component located on the reflected light path of the reflecting component, and a projection lens located at the light emitting side of the light valve modulating component.

7. The laser projection system of claim 6, further comprising: and the illumination lens group is positioned between the light combining component and the reflecting component.