Optical Engine and Laser Projection Device

Abstract

The present application discloses an optical engine and a laser projection device, belonging to the technical field of laser projection. The optical engine includes a light homogenizing component, an optical path component, a light valve component, and a lens component. Among them, the first reflector in the optical path component and the lens component can deflect the optical axes of the light homogenizing component and the lens component in the optical engine, so that the optical axis of the light homogenizing component is parallel to the second optical axis in the lens component, which can reduce the width of the optical engine, and further reduce the volume of the optical engine, and can solve the problem of the large volume of the optical engine in the related art, and can achieve the effect of reducing the volume of the optical engine.

Description

Technical Field

[0001] This application relates to the field of laser projection technology, and particularly to an optical engine and a laser projection device. Background Art

[0002] Laser projection display technology is a new type of projection display technology in the current market. Compared with light-emitting diode (LED) projection products, laser projection display technology has the characteristics of high picture contrast, clear imaging, bright colors, and higher brightness. These remarkable characteristics have gradually made laser projection display technology another mainstream development direction in the market.

[0003] An optical engine in the related art includes a light source, an optical path component, and a lens. The light beam emitted by the light source is directed towards the optical path component. The optical path component processes the beam and then directs it towards the lens.

[0004] However, the width of the optical engine in the related art is relatively large, which in turn leads to a relatively large volume of the optical engine. Summary of the Invention

[0005] Embodiments of this application provide an optical engine and a laser projection device. The technical solution is as follows:

[0006] According to one aspect of this application, an optical engine is provided. The optical engine includes: a light homogenizing component, an optical path component, a light valve component, and a lens component arranged in sequence along the optical path direction;

[0007] The light homogenizing component is used to direct the received light beam towards the optical path component. The optical path component includes a first reflector, and the first reflector is used to direct the received light beam towards the light valve component;

[0008] The lens component is used to receive the light beam exported by the light valve component along a first optical axis, and perform an optical path turning on the received light beam, transmit the light beam after the optical path turning along a second optical axis, and export it;

[0009] Wherein, the optical axis of the light homogenizing component is parallel to the second optical axis.

[0010] Optionally, the first reflector is used to receive the light beam transmitted along a first direction, and export the received light beam along a second direction, and the first direction and the second direction are perpendicular.

[0011] Optionally, the optical path component further includes a first lens, a second lens, a second reflector, and a third lens;

[0012] The first lens is used to receive the light beam emitted by the light homogenizing component, and direct the light beam towards the first reflector;

[0013] The second lens is configured to shape the light beam reflected by the first mirror and direct the light beam towards the second mirror;

[0014] The second mirror is configured to reflect the received light beam towards the third lens;

[0015] The third lens is configured to correct the received light beam and direct the received light beam towards the light valve assembly;

[0016] The light valve assembly includes a light valve and a prism unit;

[0017] The prism unit is configured to direct the light beam received from the third lens towards the light valve and export the light beam reflected by the light valve from the light valve assembly;

[0018] Wherein, the optical axis of the second lens is perpendicular to the optical axis of the first lens.

[0019] Optionally, a first plane determined by the optical axis of the first lens and the optical axis of the second lens is not coplanar with a second plane determined by the optical axis of the third lens and the first optical axis.

[0020] Optionally, the first plane is perpendicular to the second plane.

[0021] Optionally, both the second lens and the third lens are plano-convex spherical lenses.

[0022] Optionally, a surface of the third lens close to the prism unit is a plane, and a surface of the second lens away from the second mirror is a plane.

[0023] Optionally, the range of the angle between the optical axis of the third lens and the optical axis of the second lens is [90°, 110°].

[0024] Optionally, the transmission direction of the light beam exported by the light valve assembly is perpendicular to the second optical axis.

[0025] According to another aspect of the present application, a laser projection device is provided, and the laser projection device includes the above optical engine.

[0026] The beneficial effects brought by the technical solution provided by the embodiments of the present application at least include:

[0027] An optical engine is provided, which includes a light homogenizing component, an optical path component, a light valve component, and a lens component. Among them, the first mirror in the optical path component and the lens component can deflect the optical axes of the light homogenizing component and the lens component in the optical engine, so that the optical axis of the light homogenizing component is parallel to the second optical axis in the lens component, which can reduce the width of the optical engine, and further reduce the volume of the optical engine, and can solve the problem of the large volume of the optical engine in the related art, and can achieve the effect of reducing the volume of the optical engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0029] Figure 1 is a schematic structural diagram of an optical engine;

[0030] Figure 2 is a schematic structural diagram of an optical engine provided by an embodiment of the present application;

[0031] Figure 3 is Figure 2 a schematic structural diagram of the optical engine shown in one direction;

[0032] Figure 4 is Figure 2 a schematic structural diagram of the optical engine shown in another direction;

[0033] Figure 5 is Figure 4 a schematic partial structural diagram of the optical engine shown;

[0034] Figure 6 is a schematic partial structural diagram of another optical engine provided by an embodiment of the present application;

[0035] Figure 7 is a schematic structural diagram of a laser projection device provided by an embodiment of the present application;

[0036] Figure 8 is Figure 7 a schematic structural diagram of the light source component in the laser projection device shown.

[0037] Through the above drawings, the specific embodiments of the present application have been shown, and there will be more detailed descriptions later. These drawings and text descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] To make the objectives, technical solutions, and advantages of this application clearer, the following will further describe the embodiments of this application in detail with reference to the accompanying drawings.

[0039] Figure 1 It is a schematic structural diagram of an optical engine. The optical engine 10 includes a light source assembly 11, an illumination assembly 12, and a lens assembly 13. The light beam emitted by the light source assembly 11 is shaped by the illumination assembly 12 and then directed towards the lens assembly 13. The illumination assembly 12 includes a light valve. The plane where the optical axis of the light source assembly 11 is located is not parallel to the plane where the optical axis of the lens assembly 13 is located. The lens assembly 13 includes a lens group and a reflector. The light beam emitted by the illumination assembly 12 passes through the lens group, and then the transmitted lens group guides the light beam to the reflector, and the reflector reflects the light beam out of the lens assembly 13.

[0040] The optical axis of the light source assembly 11 is parallel to the x direction, and the length of the light source assembly 11 in the x direction is the width of the optical engine 10. The lengths of the optical path assembly 12 and the lens assembly 13 in the y direction are the length of the optical engine 10. The length of the lens assembly 13 in the z direction is the height of the optical engine 10.

[0041] Among them, the y direction is perpendicular to the z direction, and the direction where x is located is perpendicular to the plane determined by the y direction and the z direction. In Figure 1 the plane determined by the y direction and the z direction is a plane parallel to the paper surface, that is, the optical axis of the light source assembly 11 is perpendicular to the plane where the paper surface is located. The plane determined by the y direction and the z direction is the plane where the optical axis of the lens assembly 13 is located.

[0042] Since the length of the light source assembly 11 is relatively long, the width of the optical engine 10 is relatively long, and since the length of the lens assembly 13 in the y direction is relatively long, the length of the optical engine 10 is relatively long, resulting in a relatively large volume of the optical engine 10.

[0043] The embodiments of this application provide an optical engine and a laser projection device, which can solve the problems in the above related technologies.

[0044] As Figure 2 shown, Figure 2 It is a schematic structural diagram of an optical engine provided by an embodiment of this application. The optical engine 20 may include a light homogenizing assembly 21, an optical path assembly 22, a light valve assembly 24, and a lens assembly 23 arranged in sequence along the optical path direction. It should be noted that in order to facilitate the explanation of the positional relationship of each component in the optical engine 20 in the embodiments of this application, a three-dimensional coordinate system is introduced. Among them, the y1 direction is perpendicular to the z1 direction, the x1 direction is perpendicular to the plane determined by the y1 direction and the z1 direction, and the dimension of the optical engine 20 in the x1 direction can be referred to as the width of the optical engine 20.

[0045] AsFigure 3 As shown Figure 3 is Figure 2 a schematic structural diagram of the optical engine 20 in the first direction f1 (the direction parallel to the optical axis C1 of the light homogenizing component 21). The light homogenizing component 21 can be used to direct the received light beam to the optical path component 22. The optical path component 22 can include a first reflecting mirror 221. The first reflecting mirror 221 can be used to direct the received light beam to the light valve component 24.

[0046] The lens assembly 23 is used to receive the light beam exported by the light valve component 24 along the first optical axis C3, make a light path turn for the received light beam, transmit the light beam after the light path turn along the second optical axis C2, and export the lens assembly 23.

[0047] Wherein, the optical axis C1 of the light homogenizing component 21 is parallel to the second optical axis C2.

[0048] The first reflecting mirror 221 and the lens assembly 23 can be used to change the transmission direction of the light beam in the optical engine 20, and can make the optical axis C1 of the light homogenizing component 21 parallel to the second optical axis C2 in the lens assembly 23. That is, the optical axis C1 of the light homogenizing component 21 can be perpendicular to the x1 direction and parallel to the plane determined by the y1 direction and the z1 direction (in Figure 3 , the plane determined by the y1 direction and the z1 direction is parallel to the plane where the paper surface is located), and the size of the optical axis C1 of the light homogenizing component 21 in the x1 direction is reduced. That is, the width of the optical engine 20 in the x1 direction can be reduced. Furthermore, the volume of the optical engine 20 can be reduced. Figure 3 In

[0049] To sum up, the embodiment of the present application provides an optical engine including a light homogenizing component, an optical path component, a light valve component and a lens assembly. Among them, the first reflecting mirror and the lens assembly in the optical path component can deflect the optical axes of the light homogenizing component and the lens assembly in the optical engine, so that the optical axis of the light homogenizing component is parallel to the second optical axis in the lens assembly, the width of the optical engine can be reduced, and further the volume of the optical engine can be reduced, which can solve the problem of the large volume of the optical engine in the related art and can achieve the effect of reducing the volume of the optical engine.

[0050] Such as Figure 3As shown, in an alternative embodiment, the first mirror 221 is configured to receive a light beam transmitted along the first direction f1 and direct the received light beam along the second direction f2. The first direction f1 and the second direction f2 are perpendicular. In this way, the size of the light homogenizing component 21 in the second direction f2 can be reduced. Thereby, the length of the optical engine 20 in the second direction f2 can be reduced, and further, the volume of the optical engine 20 can be reduced. Among them, the first direction f1 and the y1 direction may be the same, and the second direction f2 and the z1 direction may be the same.

[0051] Further, as Figure 3 shown, the optical path component 22 may further include a first lens 222. The first lens 222 can be configured to receive the light beam emitted by the light homogenizing component 21 and direct the light beam towards the first mirror 221. The light homogenizing component 21 and the first lens 222 may share the same optical axis.

[0052] In an alternative example, the first lens 222 may be a positive meniscus lens. The positive meniscus lens includes two curved surfaces with similar radius of curvature and has a positive focal length. The first lens 222 can be used to converge the light beam and can also be used to correct field curvature. At this time, the light beam can be incident on the concave surface of the first lens 222.

[0053] As Figure 4 shown, Figure 4 is Figure 2 a schematic structural view of the optical engine shown looking along the optical axis of the light source component towards the optical engine. The optical path component 22 may further include a second lens 223. The second lens 223 can be configured to shape the received light beam. The second lens 223 can be used to converge the light beam emitted by the light source component 21.

[0054] Among them, as Figure 3 shown, the optical axis C4 of the second lens 223 is perpendicular to the optical axis C1 of the first lens 222 (in Figure 3 here, the optical axis C1 of the first lens 222 is parallel to the first direction f1). With such a setting, the size of the light homogenizing component 21 and the first lens 222 in the second direction f2 can be reduced, thereby reducing the overall size of the light homogenizing component 21 and the optical path component 22, and further reducing the size of the optical engine 20.

[0055] As Figure 4As shown, the optical path component 22 may further include a second reflector 224 and a third lens 225. The second reflector 224 can be used to receive the light beam emitted by the second lens 223 and reflect the received light beam towards the third lens 225. The second reflector 224 can fold the illumination optical path. On the one hand, it can meet the light input requirements of the light valve component 24. On the other hand, it can adjust the relative positional relationship between the optical path component 22 and the light valve component 24. It can make the light beam reflected by the first reflector in the optical path component 22 parallel to the light beam emitted by the light valve component 24, reduce the size of the optical engine 20 in the x1 direction, and optimize the volume of the optical engine 20.

[0056] The third lens 225 can be used to correct the received light beam and direct the received light beam towards the light valve component 24. The third lens 225 can be used to correct beam distortion, further converge the light beam, adjust the spot distribution, and balance the optical path of each field of view at the same time.

[0057] The light valve component 24 may include a light valve 241 and a prism unit 242. Among them, the light valve 241 can be a Digital Micromirror Device (DMD for short). The digital micromirror device can be regarded as an optical switch composed of many micromirrors, that is, the opening and closing of the optical switch is realized by rotating the micromirrors. The number of lenses is determined by the display resolution, and one small lens corresponds to one pixel. The micromirror is its smallest working unit and the key to affecting its performance. The volume of the micromirror is very small, but it still has a complex mechanical structure different from that of liquid crystals - each micromirror has an independent support frame and deflects positively or negatively by n degrees (n > 0) around the articulated skew axis. Two electrodes are arranged at the two corners of the micromirror, and the deflection of the micromirror can be controlled by voltage.

[0058] The micromirror works by reflecting light. When the micromirror is in the on state (i.e., the micromirror deflects +n degrees), that is, the incident angle of the incident light (light source) reaches n degrees, and the reflection angle also reaches n degrees (the sum of the two is 2n degrees). At this time, the energy of the light that the lens can receive is the largest. When the micromirror is biased towards the off state (i.e., the micromirror deflects -n degrees), the energy of the light received by the lens is the smallest and the brightness is the lowest.

[0059] The light valve can be a 0.47-inch digital micromirror device or a 0.66-inch digital micromirror device. It can also be a digital micromirror device of other sizes, and the embodiments of the present application do not limit this.

[0060] The digital micromirror device may include a chip and protective glass covering both sides of the chip. The protective glass can be used to prevent dust and moisture from entering the chip interior.

[0061] The prism unit 242 can be used to direct the light beam received from the third lens 225 to the light valve 241, and to direct the light beam reflected by the light valve 241 out of the light valve assembly 24. The prism unit 242 can be a total internal reflection (TIR) prism. Total internal reflection is an optical phenomenon in which when light passes through two media with different refractive indices, part of the light is refracted at the interface of the media and the rest is reflected. However, when the incident angle is larger than the critical angle (the light is away from the normal), the light will stop entering the other interface and be totally reflected inward. This phenomenon only occurs when light travels from an optically denser medium (a medium with a higher refractive index) to an optically less dense medium (a medium with a lower refractive index). When the incident angle is greater than the critical angle, since there is no refraction (the refracted light disappears) and only reflection occurs, it is called total internal reflection.

[0062] The prism unit 242 can include two prisms, which can be used to change the path of the light beam in the optical engine 20 and to separate the illumination light beam and the image light beam in the optical engine 20.

[0063] As Figure 5 shown, Figure 5 is Figure 4 a partial structural schematic diagram of the optical engine shown. The prism unit 242 can include a first prism 2421 surrounded by a first light incident surface D1, a reflection surface D2, and a light valve light incident surface D3, and a second prism 2422 surrounded by a second light incident surface D4, a light exit surface D5, and a bottom surface D6. The reflection surface D2 and the second light incident surface D4 can be oppositely arranged. The third lens 225 can be located outside the first light incident surface D1, the light valve 241 can be located outside the light valve light incident surface D3, and the lens assembly can be located outside the light exit surface D5.

[0064] The first light incident surface D1 can be used to receive the illumination light beam emitted by the third lens 225 and direct the illumination light beam to the reflection surface D2. The reflection surface D2 can be used to reflect the illumination light beam to the light valve light incident surface D3 so as to enter the light valve 241 through the light valve light incident surface D3. The light valve light incident surface D3 can be used to receive the image light beam processed by the light valve 241 and direct the image light beam to the reflection surface D2. The image light beam can pass through the reflection surface D2, the second light incident surface D4, and the light exit surface D5 to exit the prism unit 242 and enter the lens assembly.

[0065] As Figure 3 shown, in an alternative embodiment, the transmission direction of the light beam exported by the light valve assembly 24 is perpendicular to the second optical axis C2. In this way, the size of the lens assembly in the second direction f2 can be reduced, thereby the size of the optical engine 20 in the second direction f2 can be reduced, and further the volume of the optical engine 20 can be reduced.

[0066] AsFigure 3 As shown, in an alternative embodiment, the lens assembly 23 may include a third mirror 231, a first lens group 232, and a fourth mirror 233. The third mirror 231 may be configured to receive the light beam emitted by the light valve assembly 24 and direct the light beam towards the first lens group 232. The first lens group 232 may be configured to receive the light beam reflected by the third mirror 231 and direct the light beam towards the fourth mirror 233. The fourth mirror 233 may be configured to direct the light beam out of the lens assembly 23. The optical axis of the first lens group 232 is the second optical axis C2.

[0067] In an alternative example, the lens assembly 23 further includes a second lens group 234. The second lens group 234 is configured to receive the light beam emitted by the light valve assembly 24 and direct the light beam towards the third mirror 231. The optical axis of the second lens group 234 is the first optical axis C3.

[0068] Optionally, the turning angle of the lens assembly 23 is α, that is, α is the angle between the first optical axis C3 of the second lens group 234 and the second optical axis C2 of the first lens group 232. β is the angle between the normal of the first mirror 221 and the optical axis C1 of the first lens 222. α and β satisfy the following formula:

[0069] α + 2β = 180°;

[0070] That is, the optical axis C1 of the light homogenizing assembly 21 and the first lens 222 may be parallel to the second optical axis C2 of the first lens group 232 in the lens assembly 23, and the first optical axis C3 of the second lens group 234 may be parallel to the optical axis C4 of the second lens 223.

[0071] The first optical axis C3 of the second lens group 234 is perpendicular to the second optical axis C2 of the first lens group (in Figure 3 this case, the optical axis C2 where the first lens group is located is parallel to the first direction f1). With such a structure, the size of the lens assembly 23 in the second direction f2 can be reduced, thereby reducing the overall size of the lens assembly 23, and further reducing the volume of the optical engine 20.

[0072] Optionally, in the first lens group 232 of the lens assembly 23, the lenses arranged along the optical path direction are respectively the fourth lens and the fifth lens, which can be used for shaping the light and correcting aberrations. The fourth mirror 233 in the lens assembly 23 may be an aspherical mirror, which can be used for deflecting the light and correcting aberrations. In the second lens group 232 of the lens assembly 23, the lenses arranged along the optical path direction are respectively the sixth lens and the seventh lens, which can be used for shaping the light and correcting aberrations.

[0073] It should be noted that the lenses in the lens assembly in the embodiments of the present application may also be other types of lenses, and the lens assembly may also include other numbers of lenses. The embodiments of the present application do not limit this.

[0074] As shown Figure 5 in FIG. 2, the sixth lens 2341 in the lens assembly can be used to receive the light beam emitted from the light-emitting surface D5 of the prism unit 242, and the light-emitting surface D5 can be perpendicular to the optical axis C3 of the sixth lens 2341. The perpendicularity of the light-emitting surface D5 to the optical axis C3 of the sixth lens 2341 can make the imaging light beams at different positions emitted by the light valve 241 have equal travel distances between the light-emitting surface D5 and the sixth lens 2341, thereby improving the projection quality. Among them, the optical axis of the sixth lens 2341 is the first optical axis of the second lens group.

[0075] Optionally, the light-valve incident surface D3 of the first prism 2421 can be parallel to the light-emitting surface D5 of the second prism 2422. This can make the optical paths of the light beams emitted from different regions of the light valve 241 in the prism unit 242 the same, thereby improving the projection quality.

[0076] Optionally, the first plane determined by the optical axis of the first lens and the optical axis of the second lens (this first plane is the plane parallel to the Figure 3 paper surface shown in FIG. 2), and the second plane determined by the optical axis of the third lens and the first optical axis of the second lens group (this second plane is the plane parallel to the Figure 4 paper surface shown in FIG. 2) are not coplanar. The non-coplanarity of the first plane and the second plane can further reduce the size of the optical engine in the first direction f1.

[0077] Optionally, as shown Figure 3 in FIG. 3, the first plane is perpendicular to the second plane. In this way, the optical path assembly 22 and the light valve assembly 24 will not affect the size of the optical engine 20 in the first direction f1 (the direction parallel to the optical axis C1 where the first lens 222 is located), and the size of the optical engine 20 in the first direction f1 can be further reduced.

[0078] Optionally, as shown Figure 4 in FIG. 4, both the second lens 223 and the third lens 225 are plano-convex spherical lenses. Plano-convex spherical lenses are easier to process than aspherical lenses. This can reduce the manufacturing difficulty of the optical engine 20. Spherical lenses are abbreviated as spherical mirrors. A spherical lens is a lens whose cross-sectional curve of the curved surface is an arc, that is, an optical element composed of two coaxial refractive surfaces, usually made by grinding optical glass. The two refractive surfaces of most lenses are spherical surfaces, and one refractive surface of some lenses can be a plane. Lenses can be divided into two categories: convex lenses and concave lenses. The central part of a convex lens is thicker than the edge part, and the central part of a concave lens is thinner than the edge part. A convex lens can converge light rays and can be called a "converging lens". A concave lens can diverge light rays and can be called a "diverging lens". A single convex lens can form real images or virtual images, but a single concave lens can only form virtual images.

[0079] As shownFigure 4 As shown, in an alternative example, the surface of the third lens 225 close to the prism unit 242 is a flat surface, and the surface of the second lens 223 away from the second mirror 224 is a flat surface. The flat surfaces of the third lens 225 and the second lens 223 both face away from the second mirror 224. With such an arrangement, the third lens 225 and the second lens 223 can be used to correct aberration. The flat surface of the third lens 225 can be parallel to the light incident surface of the prism unit 242.

[0080] Optionally, the range of the angle e from the optical axis C5 of the third lens 225 to the optical axis C4 of the second lens 223 is [90°, 110°]. With such an arrangement, the third lens 225 can balance the field optical path and reduce the spot size of the light beam. The plane where the flat surface of the second lens 223 is located can be parallel to the plane where the display surface of the light valve 241 is located. In this way, the size of the optical path assembly 22 and the light valve assembly 24 in the second direction f2 can be further reduced, so that the size of the optical engine 20 in the second direction f2 can be reduced, and further the volume of the optical engine 20 can be reduced.

[0081] In an alternative implementation, as Figure 6 shown, Figure 6 is a schematic diagram of a partial structure of another optical engine provided by an embodiment of the present application. The flat surface of the third lens 225 can be glued to the light incident surface D1 of the prism unit 242, which can reduce the size of the space between the third lens 225 and the prism unit 242 and enable miniaturization of the optical engine.

[0082] Optionally, as Figure 6 shown, the optical engine provided by an embodiment of the present application may further include a galvanometer 226. The galvanometer 226 can be placed between the light valve 241 and the prism unit 242. The light valve 241 modulates the received light beam and directs it to the galvanometer 226. The galvanometer 226 processes the light beam emitted from the light valve 241 and directs it to the prism unit 242, and then through the prism unit 242 to the lens.

[0083] The galvanometer 226 may include an optical lens and a driving component. The driving component can drive the optical lens to swing continuously, and the optical lens can change the direction of the light beam accordingly.

[0084] Exemplarily, when the light beam incident on the galvanometer is a parallel light beam (i.e., the incident angles of each ray in the light beam are the same), after the optical lens in the galvanometer swings from one position to another position, the displacement distance of each pixel of the projection image corresponding to the image light beam is equal. This makes the offset amounts of each field in the projection lens to the projection screen consistent, so as to ensure high-resolution display of the visual picture. Among them, the offset amount of the field refers to the actual displacement distance of the field. The conversion from 2k or 3k resolution to 4k resolution can be achieved by the rotation of the galvanometer, reducing the system design difficulty.

[0085] After applying the galvanometer, the light valve with 2K resolution can also achieve 4K resolution when used in conjunction with the galvanometer. The light valve with 3k resolution can also achieve 4k resolution when used in conjunction with the galvanometer.

[0086] Optional, such as Figure 3 As shown, the light homogenization component 21 can be used to shape and homogenize the laser spot incident from the light source. Homogenization refers to the process of transforming a beam with uneven intensity distribution into a beam with uniform cross-sectional distribution. The light spot refers to the interference of these light beams to form bright spots or dark spots when the laser light source is used to illuminate a rough surface such as a screen or any other object that produces diffuse reflection or diffuse light transmission, resulting in a random granular intensity pattern.

[0087] The light homogenizing component may include a light pipe, which is a tubular device formed by splicing four flat reflective sheets, that is, a hollow light pipe. The light is reflected multiple times inside the light pipe to achieve the effect of homogenizing. The hollow light pipe is mainly composed of four optical elements. During assembly, a jig can be used to fix the four optical elements, and then a colloid for bonding is applied to the intersection of the optical elements to make the four optical elements join each other. Since the inner surface of the first hollow light pipe has a reflective layer, when the light beam emitted by the light source enters the first hollow light pipe through the light inlet of the first hollow light pipe, it is reflected multiple times by the reflective layer and then output from the light outlet of the first hollow light pipe, which can make the light brightness uniform. The inner wall of the first hollow light pipe can also be plated with a reflective material, such as silver, which can be used to conduct the light beam. The light pipe can also be a solid light pipe, and the light inlet and light outlet of the light pipe are rectangular with the same shape and area. The light beam enters from the light inlet of the light guide tube, and then exits from the light outlet of the light guide tube to the light valve, and the light beam is homogenized and the light spot is optimized in the process of passing through the light guide tube. The solid light guide tube can be made of quartz.

[0088] In addition, the light homogenization component may also include a compound eye lens, which is usually formed by a combination of a series of small lenses. Two rows of compound eye lens arrays are arranged in parallel to split the spot of the input laser beam, and then the split spots are accumulated through a subsequent focusing lens to achieve homogenization of the beam and optimization of the spot.

[0089] In an optical engine, the light homogenizing component may be at least one of a light guide or a fly-eye lens, which is not limited in the embodiments of the present application.

[0090] In summary, the embodiment of the present application provides an optical engine including a light homogenizing component, an optical path component, a light valve component, and a lens component. Among them, the first mirror in the optical path component and the lens component can deflect the optical axes of the light homogenizing component and the lens component in the optical engine, so that the optical axis of the light homogenizing component is parallel to the second optical axis in the lens component, which can reduce the width of the optical engine, and further reduce the volume of the optical engine, and can solve the problem of the large volume of the optical engine in the related art, and can achieve the effect of reducing the volume of the optical engine.

[0091] As Figure 7 shown, Figure 7 is a schematic structural diagram of a laser projection device provided by an embodiment of the present application. The laser projection device 30 includes a screen 31 and the optical engine 20 provided in any one of the above embodiments.

[0092] Among them, the center point of the screen 31 can be located on the optical axis of the light beam emitted by the optical engine 20, so that the display picture formed by the light beam emitted by the optical engine 20 on the screen 31 is centered, thus ensuring the picture display effect of the screen 31.

[0093] In the optical engine 20 provided by the embodiment of the present application, a first mirror is provided in the optical path component, and a second mirror is provided in the lens component. By deflecting the optical axes of the optical path component and the lens component in the optical engine 20 through the first mirror and the second mirror, the optical axis where the light homogenizing component and the first lens are located is parallel to the optical axis of the first lens group in the lens component, and further the volume of the optical engine 20 can be reduced.

[0094] Optionally, the optical axis of the first lens group in the lens component can be perpendicular to the screen.

[0095] As Figure 8 shown, Figure 8 is Figure 7 a schematic structural diagram of the light source component in the laser projection device shown. The optical engine may further include a light source component 26. The light homogenizing component in the optical engine can be a light guide tube 211. The light source component 26 may include a first laser 261, a second laser 262, and a third laser 263. Exemplarily, the first laser 261 can emit blue laser light, the second laser 262 can emit green laser light, and the third laser 263 can emit red laser light.

[0096] The light source assembly 26 may further include a first light combining lens 264 and a second light combining lens 265. The laser beam of the first color emitted by the first laser 261 and the laser beam of the second color emitted by the second laser 262 may be vertically arranged. The laser beam of the first color and the laser beam of the second color are combined by the first light combining lens 264. The light combining lens 264 may include reflective lenses with intervals. The reflective lenses may allow the laser beam of the first color to pass through directly while reflecting the laser beam of the second color. After the laser beam of the second color is reflected by the first light combining lens, it has the same propagation direction as the laser beam of the first color. The first light combining lens 264 may also be a dichroic mirror, which has the function of transmitting the laser beam of the first color and reflecting the laser beam of the second color.

[0097] The laser beam of the first color and the laser beam of the second color passing through the first light combining lens 264 are combined with the laser beam of the third color again by the second light combining lens 265, and finally the three-color laser beams are emitted in the same direction.

[0098] The light source assembly 26 may further include a beam reducing lens group 266, a rectangular mirror 267, and a condenser lens 268. The shaping lens group 266 may be used to reduce the beam of the laser emitted by the laser and direct the beam to the rectangular mirror 267. The rectangular mirror 267 may change the propagation direction of the beam and can reduce the size of the light source assembly in the length direction of the light guide tube 211.

[0099] Compared with the LED light source, the laser light source can reach a higher color gamut level. The light source unit in the embodiment of the present application may include a light converter, which receives the laser from the laser light source and converts the laser into visible light of various colors to be provided to the light homogenizing component.

[0100] The current solutions for projection devices are Digital Light Processing (DLP, in which the image signal needs to be digitally processed first and then the light is projected) and Liquid Crystal Display (LCD). Among them, LCD utilizes the electro-optical effect of liquid crystals. By controlling the transmittance and reflectance of liquid crystal cells through a circuit, images with different gray levels and colors are generated. The main imaging device of LCD is the liquid crystal panel, and the light on the red, green, and blue liquid crystal panels is transmitted through a lens and a reflector. The DLP working mode mixes colors by rotating a color wheel at high speed and finally transmits the light through a prism. However, both of these methods require the use of a bulb, and the bulb has a lifespan, and the picture brightness and color purity are relatively low.

[0101] In the laser projection device according to the embodiment of the present application, compared with the two projection devices of LCD and DLP, it has a longer working life, will not cause the screen brightness to dim due to long-term work, and has a relatively wide color gamut.

[0102] In summary, the embodiment of the present application provides a laser projection device. Among them, the first reflector and the lens assembly in the optical engine can deflect the optical axis of the light homogenizing assembly and the lens assembly in the optical engine, so that the optical axis of the light homogenizing assembly is parallel to the second optical axis in the lens assembly, which can reduce the width of the optical engine, and further reduce the volume of the optical engine, and can solve the problem of the large volume of the optical engine in the related art, and can achieve the effect of reducing the volume of the optical engine.

[0103] In the present application, the terms "first", "second", "third", "fourth", "fifth", "seventh" and "eighth" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0104] The above are only the optional embodiments of the present application, and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An optical engine, characterized in that, The optical engine includes a light homogenizing component, an optical path component, a light valve component, and a lens component that are sequentially arranged along the optical path direction; The light homogenizing component is used to direct the received light beam to the optical path component. The optical path component includes a first lens, a second lens, a first mirror, a second mirror, and a third lens. The first lens is used to receive the light beam emitted by the light homogenizing component and direct the light beam to the first mirror; The first mirror is used to direct the received light beam to the second lens. The second lens is used to shape the light beam reflected by the first mirror and direct the light beam to the second mirror; The second mirror is used to reflect the received light beam towards the third lens. The third lens is used to correct the received light beam and direct the received light beam to the light valve component; The lens component includes a second lens group, a third mirror, a first lens group, and a fourth mirror. The second lens group is used to receive the light beam exported by the light valve component and direct the light beam to the third mirror. The third mirror is used to reflect the received light beam towards the first lens group; The first lens group is used to receive the light beam reflected by the third mirror and direct the light beam reflected by the third mirror to the fourth mirror. The fourth mirror is used to export the light beam from the lens component. The optical axis of the second lens group is the first optical axis, the optical axis of the first lens group is the second optical axis, and the first optical axis is perpendicular to the second optical axis; Wherein, the straight line where the optical axis of the light homogenizing component is located coincides with the straight line where the optical axis of the first lens is located and is parallel to the second optical axis; The optical axis of the second lens is perpendicular to the optical axis of the first lens. The first plane determined by the optical axis of the first lens and the optical axis of the second lens is not coplanar with the second plane determined by the optical axis of the third lens and the first optical axis.

2. The optical engine according to claim 1, characterized in that, The first mirror is used to receive the light beam transmitted in the first direction and export the received light beam in the second direction, and the first direction is perpendicular to the second direction.

3. The optical engine according to claim 2, characterized in that, The light valve component includes a light valve and a prism unit; The prism unit is used to direct the light beam received from the third lens to the light valve and export the light beam reflected by the light valve from the light valve component.

4. The optical engine according to claim 1, characterized in that, The first plane is perpendicular to the second plane.

5. The optical engine according to claim 3, characterized in that, Both the second lens and the third lens are plano-convex spherical lenses.

6. The optical engine according to claim 5, characterized in that, The surface of the third lens close to the prism unit is a plane, and the surface of the second lens far from the second mirror is a plane.

7. The optical engine according to claim 1, characterized in that, The range of the angle from the optical axis of the third lens to the optical axis of the second lens is [90°, 110°].

8. The optical engine according to any one of claims 1 to 7, characterized in that, The transmission direction of the light beam exported by the light valve component is perpendicular to the second optical axis.

9. A laser projection device, characterized in that, An optical engine according to any one of claims 1 to 8 is included.

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