WO2022017144A1 - Laser light source and laser projection device - Google Patents

Abstract

Disclosed are a laser light source (10) and a laser projection device (00). The laser light source (10) comprises a laser (120) which at least emits a blue laser and a red laser; and a first lens (1041), a first diffusion portion (105) and a second lens (1042) that are sequentially arranged in a light emergence direction of the light source (10), wherein the first lens (1041) is configured for converging at least the blue laser and the red laser to the first diffusion portion (105), the first diffusion portion (105) is configured for expanding the divergence angles of at least the blue laser and the red laser and then emitting the expanded blue laser and red laser to the second lens (1042), the second lens (1042) is configured for converging at least the blue laser and the red laser that are in a divergent state, the focal point of the second lens (1042) is located between the first lens (1041) and the second lens (1042), the first diffusion portion (105) is located at a focal plane of the second lens (1042), and the size of a light spot emergent from the second lens (1042) is smaller than that of a light spot incident on the incident side of the first lens (1041).

Description

Laser light source and laser projection equipment

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of the Chinese patent application with the application number 202010706291.1 and the invention title "Laser Light Source and Laser Projection Equipment" filed with the China Patent Office on July 21, 2020, the entire contents of which are incorporated into this application by reference.

technical field

The present application relates to the field of projection technology, and in particular, to a laser light source and a laser projection device.

Background technique

With the development of display technology, the requirements for the display effect of the projection screen of the laser projection device are getting higher and higher.

The laser light source has the advantages of good monochromaticity, high brightness and long life, and is an ideal light source. As the power of laser devices increases to meet the requirements of industrial applications, lasers are gradually used as light sources for illumination. For example, in recent years, lasers have been used as projection light sources in projection equipment, gradually replacing mercury lamp illumination. Compared with LED light sources, lasers also have the advantages of small etendue and high brightness.

Lasers are divided into blue lasers, red lasers and green lasers according to the type of light emission, which emit blue lasers, red lasers and green lasers respectively. Among them, blue lasers were the first to be industrially applied, and red and green lasers were limited by the reason for their power increase (such as less than 1W luminous power, low brightness), and could not be applied for a long time before. Most of the laser projection light sources are mixed laser light sources of monochromatic laser (blue laser) and fluorescence, and fluorescence is excited by blue laser.

A solid-state laser is essentially a PN junction semiconductor, as shown in Figure 1-1. The schematic diagram of the laser light-emitting chip. Between the P-type semiconductor and the N-type semiconductor is the active layer, also known as the active region. The oscillation of the resonator in the active region will cause lasers of different wavelengths to be emitted from the front cavity surface. Specifically, as shown in Figure 1-2, the laser beam is emitted in a radial beam from the light-emitting point. The axis diverges faster and the angle is larger, and the slow axis diverges relatively slowly and the angle is smaller, so that the shape of the laser beam is elliptical.

Among them, blue laser and green laser can be generated by using gallium arsenide luminescent material, and red laser can be generated by using gallium nitride luminescent material. Due to the different light-emitting mechanisms of the luminescent materials, the red laser has a low luminous efficiency and a high thermal conversion rate in the process of generating various color lasers. The luminous efficiency of the blue laser and the green laser is relatively high, and the corresponding chip can meet the luminous demand by setting a luminous point. In order to meet the requirements of luminous power, as shown in Figure 1-3, the red laser chip usually sets multiple luminous points, such as X1, X2, to increase the luminous power, which also causes the size of the red laser beam to be relatively large. At the same time, due to the different luminescence mechanisms of the luminescent materials, the divergence speed of the fast and slow axes of the red laser is greater than that of the blue laser and the green laser.

The package structure of the chip is usually the same in appearance. Therefore, even under the same package structure, due to the different degrees of divergence of the fast and slow axes, the red laser is more effective than the laser beam emitted by the blue and green lasers when applied. The divergence angle of the red laser is large, the degree of diffusion is large, and the spot size of the red laser will also be larger, which will affect the color coincidence of the red laser and other color lasers.

SUMMARY OF THE INVENTION

An aspect of the embodiments of the present application provides a laser light source, including a laser, at least emitting a blue laser and a red laser;

The first lens, the first diffuser and the second lens are arranged in sequence along the light emitting direction of the light source, and the first lens is used for condensing the blue laser and the red laser to the first diffuser;

The first diffusing part is used to expand the divergence angles of the blue laser and the red laser and then shoot toward the second lens;

The second lens is used to converge the divergent blue laser and red laser,

The focal point of the second lens is located between the first lens and the second lens, the first diffuser is located at the focal plane of the second lens, and the size of the light spot emitted by the second lens is smaller than the size of the light spot incident on the incident side of the first lens. size.

And, another aspect of the embodiments of the present application also provides a laser projection device, including:

In the laser light source, light valve and lens of the above embodiment, the laser light source is used to emit light to the light valve, the light valve is used to modulate the incident light and then shoot it towards the lens, and the lens is used to project the incident light.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present application more clearly, the following briefly introduces the drawings that are used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

Figure 1-1 is a schematic diagram of a related art laser light-emitting chip;

Figure 1-2 is a schematic diagram of the principle of the related art laser light-emitting chip emitting light beam;

Figures 1-3 are schematic diagrams of the principle structure of a red laser light-emitting chip in the related art;

FIG. 2 is a schematic structural diagram of a laser projection device according to an embodiment of the present application;

3-1 is a schematic diagram of an optical path of a laser light source according to an embodiment of the present application;

3-2 is a schematic diagram of an optical path of another laser light source provided by an embodiment of the present application;

3-3 is a schematic diagram of an optical path of another laser light source provided by an embodiment of the present application;

3-4 are schematic diagrams of optical paths of still another laser light source according to an embodiment of the present application;

FIG. 4 is a schematic plan view of a diffuser component provided by an embodiment of the present application;

5 is a schematic structural diagram of a laser used in an embodiment of the application;

6 is a schematic structural diagram of a laser light source according to an embodiment of the present application;

7 is a schematic diagram of an optical path of a laser projection device provided by an embodiment of the present application;

8 is a schematic diagram of an optical path of another laser projection device provided by an embodiment of the present application;

9 is a schematic diagram of a partial optical path of a laser projection device provided by an embodiment of the present application;

FIG. 10 is a schematic structural diagram of another laser projection device provided by an embodiment of the present application.

detailed description

In order to make the objectives, technical solutions and advantages of the present application clearer, the embodiments of the present application will be further described in detail below with reference to the accompanying drawings.

Throughout the specification and claims, the term "comprising" is to be interpreted in an open, inclusive sense, ie, "including, but not limited to," unless the context requires otherwise. In the description of the specification, the terms "one embodiment," "some embodiments," "exemplary embodiments," "example," "specific Specific features, structures, materials or characteristics are included in at least one embodiment or example of the present disclosure. Schematic representations of the above terms do not necessarily refer to the same embodiment or example. In addition, the specific features, structures, materials or characteristics described may be included in any one or more embodiments or examples in any suitable manner.

Hereinafter, the terms "first" and "second" are only used for descriptive purposes, and should not be construed as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, a feature defined as "first" or "second" may expressly or implicitly include one or more of that feature. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.

First, the technical solution of the present application is applied to a laser projection device. Figure 2 shows an example of the structure of a laser projection device. First, according to the example of the laser projection device shown in FIG. 2 , the structure and working process of the laser projection device of this embodiment will be described.

As shown in FIG. 2 , the laser projection device 00 includes a whole casing 011 and a base 012 . The whole casing 011 and the base 012 form an accommodating space, and in the accommodating space, it also includes a light source assembled on the base 012 10, the optical machine 20, and the lens 30, these three parts constitute the optical engine part, and are connected in sequence along the beam propagation direction. Each of the three major parts is packaged with a corresponding casing to support the optical components and make each optical part meet certain sealing or airtight requirements.

A plurality of circuit boards 40 are also included in the accommodating space formed by the whole casing 011 and the base 012 . The plurality of circuit boards 40 are parallel to each other, and are vertically arranged on the base 012 on the inner side of the whole casing 011 .

In a specific implementation, see FIG. 2 , wherein the optical machine 20 and the lens 30 are connected and arranged along the first direction of the whole machine. For example, the first direction may be the width direction of the whole machine, or according to the usage mode, the first direction Opposite to the viewing direction of the user, the connection direction of the light source 10 and the optical engine 20 is perpendicular to the first direction, so that the optical engine part composed of the light source 10, the optical engine 20 and the lens 30 is connected in an "L" shape. The optomechanical is located at the corner of the "L" shape. As a result, the optical axis is turned 90 degrees, so that the length of the optical path in one direction is compressed.

Referring to FIG. 2 , the laser projection apparatus 00 further includes a plurality of circuit boards 40 , and the plurality of circuit boards 40 are arranged vertically with respect to the bottom plate 102 and along the inner side of the whole casing 011 . In the drawings, only a part of the whole casing 011 is schematically represented. Specifically, a plurality of circuit boards 40 are arranged in parallel with each other, and are arranged close to the inner side of the whole machine casing 011. Generally, the whole machine casing 011 is a cover body including a top cover. part.

The plurality of circuit boards 40 include a power supply board, also called a power board, which is used to provide power for multiple modules of the device; a display board, which is mainly used to control the imaging of the projection system, which is a DLP system in this embodiment, such as a DMD chip signal. The generation of the light source timing signal and the output of the PWM brightness dimming signal; the signal transmission board, also known as the TV board, is mainly used to decode the video signal to form an image signal and transmit it to the display board for further image processing.

The above-mentioned light source 10 is a laser light source, and a laser can be used to emit at least red laser light and blue laser light. For the sake of simplicity, the following example takes the laser emitting red laser and blue laser as an example for description.

In an example, as shown in 3-1, a schematic diagram of a laser light source according to an embodiment of the present application. As shown in FIG. 3-1, the laser light source includes a laser 120, which emits at least blue laser and red laser, and the laser 120 can be two groups of lasers that emit different colors. The first lens 1041 , the first diffuser 105 and the second lens 1042 are sequentially arranged along the light emitting direction of the light source. The first lens 1041 is specifically a convex lens, and is used for condensing the above-mentioned at least color laser light and red laser light to the first diffusion part 105 .

The first diffusing part 105 , specifically a diffusing sheet, is used to expand the divergence angles of at least the blue laser and the red laser, and then radiate toward the second lens 1042 . For example, when the first diffuser 105 is a diffuser with a uniform diffusion angle, the degree of divergence of the transmitted red laser and blue laser is basically the same. For example, in the red laser and blue laser The original divergence angle is changed or increased by 5 degrees, so that the range of the divergence angle of the red laser and the blue laser has been expanded. In terms of the change of the fast axis divergence angle, the original fast axis divergence angle of the red laser beam is 30 degrees, and the original fast axis divergence angle of the blue laser beam is 15 degrees, then after passing through the first diffuser 105, the red laser beam fast axis The divergence angle increases by 5 degrees to 35 degrees, and the fast axis divergence angle of the blue laser beam also increases by 5 degrees to 20 degrees. Although the difference between the two divergence angles remains basically unchanged, the divergence angle The degree of difference is changed from 100% ((30-15)/15) to 75% ((35-20)/20), and the difference is reduced, so that when the red laser beam and the blue laser beam are combined, the two If the degree of divergence is close, the degree of coincidence of the light spots will also increase.

The second lens 1042, specifically, a convex lens, is used for converging the above-mentioned blue laser and red laser in a diverging state, compressing the divergence angle of the red laser and the blue laser, and reducing the size of the beam spot.

The focal point of the second lens 1042 is located between the first lens 1041 and the second lens 1042, and the first diffuser 105 is located at the focal plane of the second lens 1042. In this way, the first diffuser 105 is equivalent to being located in the second lens 1042. For a surface light source at the focal plane, a partial area of the first diffuser 105 can be regarded as a point light source located at the focal position of the second lens 1042 . Regardless of the size of the second lens, when the light beam emitted from this part, which is regarded as a point light source, irradiates the second lens 1042, according to the imaging principle, the light beam at any angle emitted by the point light source will be converged by the second lens 1042. Straight out into a parallel beam. When the light beams of the surface light source parts other than the point light source area are incident on the second lens 1042, they will also be converged to a certain extent.

Therefore, the size of the light spot of at least the blue laser and the red laser converged by the second lens 1042 is smaller than the size of the light spot after being converged by the first lens 1041 and before entering the first diffuser 105 . After the laser beam passes through the first lens 1041, the first diffuser 105 and the second lens 1042 in sequence, the laser beam spots with different degrees of divergence and different colors, such as red laser and blue laser, have divergence angles at this time. It has been enlarged, and the difference in the degree of divergence has also been reduced, so that the degree of coincidence during light combining is improved, which is beneficial to reduce the color cast of the combined light spot, and the spot size of different color laser beams is reduced.

And, Figures 3-2 illustrate another embodiment of a laser light source. In the laser light source shown in FIG. 3-2 , the first lens 1041 and the second lens 1042 are both convex lenses, and their focal points overlap, and the overlapped focal point is located between the first lens 1041 and the second lens 1042 .

The first diffuser 105 is located at the focal point. Optionally, the optical axes of the first lens 1041 and the second lens 1042 may be collinear.

In this way, the first lens 1041 can condense the light incident from the laser 120 to its focal point, so the first lens 1041 can condense the light emitted by the laser 120 to the first diffuser 105. It should be noted that although the first diffuser 105 In terms of structure, it can be a sheet-like structure such as a diffuser, but according to optical principles, it can be regarded as a point light source here. The first diffusing part 105 is used to expand the divergence angle of the incident light rays and then send them to the second lens 1042 . The second lens 1042 receives light beams with multiple divergence angles from the focal point and collimates them into parallel light beams. Since the first diffuser 105 is located at the focal point of the first lens, the light beams incident on the first lens 1041 will converge here to form a point light source, and the focal point is also the focal point of the second lens 1042. According to the optical imaging In principle, the light beam emitted from here will be collimated into a parallel light beam by the second lens 1042 no matter what angle is incident on the second lens 1042 (assuming that the size of the second lens is not considered). In this way, the first diffusing part 105 can be set to have a large divergence angle, and even after the red laser and blue laser are diverged to a large extent, they can still be output as parallel beams, so the red laser can be output to a large extent. The laser and blue laser are diffused and homogenized to reduce the difference in the degree of divergence of different color beams.

The light emitted by the light source to the first lens 1041 may be parallel to the optical axis of the first lens 1041 , or substantially parallel to the optical axis (that is, the included angle between the light and the optical axis is smaller than a certain angle threshold). Since the convex lens can focus light parallel to the optical axis at the focal point, and the convex lens can change the light incident from its focal point into light parallel to the optical axis. Therefore, the light emitted by the light source can be concentrated at its focal point after passing through the first mirror 1041, and the light can be re-emitted to the second lens 1042, and become parallel light through the second lens 1042, so that the first lens 1041 and the second lens 1042 can form a beam reduction system to reduce beams incident on the first lens. The spot area on the first lens 1041 is larger than the spot area on the second lens 1042 . That is, the area of the spot formed by the light emitted from the light source on the first lens 1041 is larger than the area of the spot formed by the light emitted from the first diffuser 105 on the second lens 1042 .

In the embodiment of the present application, since the light rays converge at the focal point and then continue to be transmitted to the second lens 1042 , the spot area on the first lens 1041 is larger than the spot area on the second lens 1042 . That is to say, the lens group composed of the first lens 1041 and the second lens 1042 can condense the input light beam to ensure that more light is emitted to the subsequent optical components for forming a projection image, and to ensure that the utilization rate of light is high.

In the above embodiment of the laser light source shown in FIG. 3-1 or FIG. 3-2 , the first diffuser 105 can be a diffuser in a moving state, such as a moving diffuser, which can rotate or vibrate.

Moreover, in the above embodiments of the laser light source, the ratio of the spot area on the incident side of the first lens 1041 to the spot area on the exit side of the second lens 1042 ranges from 1.5 to 3.

And, in the above embodiments of the laser light source, the focal length of the first lens 1041 is greater than the focal length of the second lens 1042 .

And, in the above embodiments of the laser light source, the laser 120 also emits green laser light. Among them, the red laser, the blue laser, and the green laser can be sequentially emitted in sequence.

And, as an improvement of the above examples of multiple laser light sources, FIG. 3-3 shows an optical schematic diagram of still another laser light source.

As shown in FIG. 3-3 , the first diffusion part 105 is in a moving state and is driven by the first driving structure 107 . And, the example of the laser light source further includes a second diffusing part 109 , which is disposed in the path where the laser light emitted by the light source enters the first lens 1041 , that is, between the laser 120 and the first lens 1041 .

The second diffusion part 109 may be a fixed diffusion sheet.

And, FIG. 3-4 also shows another example of a laser light source. Different from the example shown in FIG. 3-3 above, the laser light source also has a second diffusing part 106, and the second diffusing part 106 is driven by the second The structure 108 performs a driving motion. The second diffuser 106 is disposed behind the second lens 1042 and is located in the exit path of the parallel light beam.

It should be noted that, in the laser light source shown in FIGS. 3-4 , the second diffuser 106 may also be a fixed diffuser.

Also, in the laser light sources of the above examples, the divergence angle of the second diffusing portion 106 or 109 is smaller than the divergence angle of the first diffusing portion 105 .

The divergence angle of the first diffusion part 105 may range from 5 degrees to 16 degrees.

And, in the laser light sources of the above examples, as an improvement, the first diffusing part 105 may have multiple sub-regions, as shown in FIG. 4 , taking two sub-regions as an example. The first partition 1051 may be used to transmit through the red laser light, and the second partition 1052 may be used to transmit through the blue laser light or the green laser light. In addition, the diffusion angle of the first sub-area 1051 is smaller than the diffusion angle of the second sub-area 1052. For example, the diffusion angle of the first sub-area 1051 to the light is 6 degrees, and the diffusion angle of the second sub-area 1052 to the light is 9 degrees. After the red laser with a divergence angle of 30 degrees passes through the first partition 1051, the divergence angle increases to 36 degrees, while the divergence angle of the blue laser or green laser with an original divergence angle of 15 degrees increases to 24 degrees, so the difference between the two is It is 50%. By setting different divergence angles, the light with a smaller original divergence angle can be diverged to a greater extent, which can further reduce the difference in divergence degrees of laser beams of different colors, thereby helping to improve the color of the combined light spot. Coincidence degree.

In one example, the laser 120 may be an MCL type laser, such as the structure shown in FIG. 5 . Among them, there can be at least three groups of MCL lasers, emitting red lasers, blue lasers, and green lasers respectively. Each group of lasers can have the structure shown in FIG. Alternatively, the laser 120 is a group of MCL-type lasers, including multiple light-emitting chips arranged in rows and columns, respectively emitting red laser, blue laser, and green laser. Specifically, referring to FIG. 5 again, the laser may include a first light emitting area 2001, a second light emitting area 2002, and a third light emitting area 2003 disposed on the same substrate, wherein the first light emitting area, the second light emitting area, and the third light emitting area The regions are arranged adjacently in sequence, and the area of the third light emitting region is larger than that of the first light emitting region and the second light emitting region.

In a specific implementation, the first light-emitting region may emit blue laser light, the second light-emitting region may emit green laser light, and the third light-emitting region may emit red laser light.

As shown in FIG. 5 , the above three light-emitting regions are located on the same laser package component, that is, the light-emitting chips of the three-color laser are arranged in an array and packaged in a module. For example, the MCL laser used in this example is a 4×5 light-emitting device. array. The laser assembly includes a substrate 2010, a plurality of light-emitting chips are packaged on the substrate 2010, and a collimating lens group 2012 is further provided at the position of the light-emitting surface of the laser assembly. The light-emitting surface of the laser component has multiple light-emitting areas, and the light beams emitted from different light-emitting areas have different colors. One row glows green, one glows blue, and the remaining two glow red. The above-mentioned laser assembly encapsulates the three-color light-emitting chips together, and has a small volume, which is beneficial to reduce the volume of the light source device.

It should be noted that the laser components in this example are not limited to the above-mentioned 4X5 array, and can also be other array arrangements, such as 3X5 array or 2X7 array, as long as it can emit three-color laser beams.

FIG. 6 shows a specific structure of a laser 120 . As shown in FIG. 6 , a plurality of light-combining lenses 1201 , 1202 , 1203 are arranged corresponding to different light-emitting areas of the MCL laser, all of which are used to refract the light beams emitted from the corresponding light-emitting areas by 90 degrees and then radiate toward the light-emitting port of the light source. The multiple light-combining lenses are arranged in sequence toward the light exit of the laser light source, and at least one light-combining lens can transmit the light beams of the corresponding colors from other light-emitting areas, combine the reflected light beams, and emit in the direction of the light exit of the laser light source. . Specifically, the first light combining lens 1201 is used to receive the light beam emitted by the first light emitting area, the second light combining lens 1202 is used to receive the light beam emitted by the second light output area, and the third light combining lens 1203 is used to receive the third light output area. emitted beam. The difference between the light receiving surfaces of the first light combining lens 1201, the second light combining mirror 1202 and the third light combining mirror 1203 and the first color laser beam, the second color laser beam and the third color laser beam emitted from the light emitting area of the laser assembly 110. The included angle between them can be set to 45°±2°, wherein the first light combining lens 1201 is a reflective mirror, the second light combining lens 1202 and the third light combining lens 12033 are all dichroic mirrors. The first light-combining lens 1201 , the second light-combining lens 1202 and the third light-combining lens 1203 are arranged parallel to each other.

The first light-combining lens 1201 is a reflecting mirror for reflecting the laser beam of the first color. The second light combining lens 1202 is used to reflect the laser beam of the second color and transmit the laser beam of the first color, and is a dichroic mirror. The third light combining lens 1203 is used to reflect the laser beam of the third color and transmit the laser beam of the first color and the second color. The third light combining lens 1203 is a dichroic mirror.

Wherein, the spot size of the first color laser beam and the second color laser beam is smaller than the spot size of the third color laser beam, and the beam angle of the first color laser beam and the second color laser beam and the angle of the third color laser beam Specifically, the parallelism of the first color laser beam and the second color laser beam is smaller than that of the third color laser beam, that is, the divergence angle of the third color laser beam is greater than that of the first color laser beam and the second color laser beam. The divergence angle of the color laser beam.

The third color laser is red laser, and the first color laser and the second color laser are blue laser and green laser.

It can be known from the above example that among the light beams emitted by the laser 120, the size of the red laser beam is larger than that of the blue laser and the green laser.

And, when the light beam emitted by the above-mentioned laser 120 is collected by a light collecting device, such as a light rod, for example, the light spot distribution measured on the light entrance surface of the light rod will show a relatively obvious color boundary phenomenon between the inner and outer circles, for example, the converged light spot is approximately a circle. The outermost circle is red, and the inner circle is purple, blue and other different concentric circles. The above phenomenon shows that the three-color laser beams have the phenomenon of spot boundary and uneven color distribution of combined light. And this phenomenon will lead to the degradation of the projected image quality.

Through the laser light source scheme of the above example, the first diffuser is located at the focal point of the second lens and between the first lens and the second lens, especially when the focal points of the first lens and the second lens are coincident, the first diffuser A wide range of divergence angles can be set in the part to spread the incident laser beam to a large extent, so that the homogenization effect of the laser beam is good. The second lens converges or is in a collimated state. Specifically, the part of the light source incident on the first diffuser and located at the focal point of the second lens can be regarded as a point light source, and the part of the light beam exiting through the first diffuser can be The two lenses are collimated into parallel or nearly parallel beams, and the part of the beam that is not incident at the focal position forms a surface light source at the focal plane. This part of the light source can still be compressed by the second lens to converge the beam divergence angle.

In this way, through the above-mentioned scheme of the laser light source, the original laser beams with different divergence angles and different colors can be diverged at a larger angle, but the improvement rates of the divergence angles are different, so that the laser beams of different colors pass through the first diffuser. The difference of the divergence angle of the beam can be reduced, the coincidence of the combined light spot can be improved, the phenomenon of color circle and color cast can be reduced or avoided, and the picture quality of the projected image can be improved.

The following embodiments of the present application provide a laser projection device, and the display effect of the projection screen of the laser projection device can be better. In addition, the laser projection apparatus can also be easily miniaturized.

FIG. 7 is a schematic structural diagram of a laser projection device provided by an embodiment of the present application. As shown in FIG. 7 , the laser projection device 00 includes: a laser 120, a light valve 103 and a lens 30. The laser 120 is used to emit light to the light valve 103, and the light valve 103 is used to modulate the incident light and then shoot it toward the lens 30, The lens 30 is used to project the incident light.

The laser projection apparatus 00 further includes: a first lens 1041 , a first diffuser 105 , a second lens 1042 and a light homogenizing member 101 located in the optical path between the laser 120 and the light valve 103 . For example, the first lens 1041 , the first diffuser 105 , the second lens 1042 and the light homogenizing member 101 may be sequentially arranged along the light exit direction of the laser 120 (the x direction in FIG. 7 ). Preferably, in the optical path of the laser projection apparatus in this example, the focal points of the first lens 1041 and the second lens 1042 are coincident, and the coincident focal points are located between the first lens 1041 and the second lens 1042 . The first diffuser 105 is located at the focal point. Optionally, the optical axes of the first lens 1041 and the second lens 1042 may be collinear. And, both the first lens 1041 and the second lens 1042 are convex lenses.

The first lens 1041 can condense the light incident from the laser 120 to its focal point, so the first lens 1041 can condense the light emitted by the laser 120 to the first diffusing part 105, which is used for diffusing the incident light After the angle is enlarged, it shoots toward the second lens 1042 . The second lens 1042 is used to send the incident light to the light homogenizing part 101 , and the light homogenizing part 101 is used to homogenize the incident light and then shoot it to the tube valve 103 . The first lens 1041 and the second lens 1042 can form a beam reduction system to reduce the beam incident on the first lens, so the spot area on the first lens 1041 is larger than that on the second lens 1042 . That is, the area of the light spot formed on the first lens 1041 by the light emitted from the light source is larger than the area of the light spot formed by the light emitted from the first diffuser 105 on the second lens 1042 .

Optionally, the light emitted by the light source to the first lens 1041 may be parallel to the optical axis of the first lens 1041, or substantially parallel to the optical axis (ie, the angle between the light and the optical axis is smaller than a certain angle threshold). Since the convex lens can focus light parallel to the optical axis at the focal point, and the convex lens can change the light incident from its focal point into light parallel to the optical axis. Therefore, after passing through the first lens 1041 , the light emitted by the light source can be converged at its focal point, and the light can be re-emitted to the second lens 1042 and become parallel light through the second lens 1042 . At this time, the laser 120 may not include a condensing lens, or replace the condensing lens with a collimating lens, so as to ensure that the light emitted by the light source to the optical machine is parallel light or approximately parallel light.

In the embodiment of the present application, since the light rays converge at the focal point and then continue to be transmitted to the second lens 1042 , the spot area on the first lens 1041 is larger than the spot area on the second lens 1042 . That is, the lens group composed of the first lens 1041 and the second lens 1042 can condense the input light beam to ensure that more light is directed to the uniform light component for forming a projection image, and to ensure a high utilization rate of the light.

In the embodiment of the present application, the first diffusing part is located at the focal point of the first lens and the second lens, so even if the diffusing angle of the first diffusing part can be set to be larger, it can be ensured that the light emitted from the first diffusing part can be regarded as The point light source is emitted toward the second lens, and becomes approximately parallel light. In this way, the laser projection device can reduce the divergence degree of laser beams of different colors and originally have different divergence angles on the basis of not affecting the beam shrinking of light and ensuring the utilization rate of light. At the same time, by expanding the divergence angle of the light emitted by the light source, the homogenization of the laser beam can be improved, thereby reducing the speckle effect of the laser projection equipment and improving the display effect of the projection screen of the laser projection equipment. In addition, since the loss of the light radiating to the homogenizing part is less, the light utilization rate of the homogenizing part can be guaranteed to be high.

In addition, in the embodiment of the present application, the first diffuser is located at the focal point of the first lens and the second lens. Even if the diffusion angle of the first diffuser is relatively large, it will not affect the constriction of the light by the first lens and the second lens. , so the diffusion angle of the first diffusion part can be larger, ensuring a better effect of eliminating the speckle effect.

It should be noted that, when the focal points of the first lens and the second lens do not coincide, and the first diffuser is located at the focal plane of the second lens, it can also have the effect of greatly changing the degree of divergence of the laser beam. , which is different from the case where the focal points of the first lens and the second lens overlap, when the focal points of the two overlap, the light entrance or exit of the first diffuser can be regarded as a point light source. The diffusion angle of the laser beam is diffused and the divergence angle of the laser beam is changed, it can still be collimated into a parallel beam by the second lens, and the incident side of the first lens is also a parallel beam. In this way, for the first lens and the second lens For an optical system composed of two lenses, the incident light and the outgoing light are both parallel beams, and the outgoing spot size is reduced, which can simultaneously achieve the purpose of beam reduction. The above description is also applicable to the case of the aforementioned embodiments of the laser light source.

And, in the embodiment of the present application, the first diffuser is arranged between the first lens and the second lens, and the optical processing of beam divergence and beam reduction is performed at the same time, and there is no need to separately set the position for setting the first diffuser. The components in the device are compactly arranged, so the speckle effect can be reduced and the volume of the laser projection device can be kept small.

To sum up, in the laser projection device provided by the embodiments of the present application, the first lens, the first diffuser, the second lens and the light homogenizing component are sequentially arranged on the optical path between the light source and the light valve. The focal points of the first lens and the second lens overlap, and the spot area on the first lens is larger than that on the second lens. The first lens and the second lens can condense the light emitted by the light source to ensure that more light is emitted. It is directed to the uniform light component to form a projection screen to ensure a high utilization rate of light. And since the first diffuser is located at the coincident focal point, the light beam can be regarded as a point light source after the light beam converges here. Any beam angle emitted to the lens can be collimated into a parallel beam by the lens. Therefore, the first diffuser can be set to a larger divergence angle to diffuse the incident laser beam to a greater extent, so that the laser beam is evenly distributed. The laser beam after being diffused by a large angle can still be condensed into a collimated state by the second lens after it is emitted to the second lens.

On the other hand, the spot size of the laser beam collimated by the second lens is reduced, so that the beam reduction of the laser beam is realized, thereby facilitating the utilization of the rear optical lens. In the above technical solution, there is no need to additionally set a special optical path position for the first diffuser, but it is located between the two original lenses, which can reduce the beam, improve the coincidence of the light spots of different colors, and dissipate the multiplicity of the spots. effect without increasing the length of the optical path.

Therefore, the laser projection equipment can reduce the divergence difference of laser beams of different colors and different divergence angles by expanding the divergence angle of the light emitted by the light source without affecting the beam shrinkage and ensuring that the light utilization rate and the optical path length do not increase. , improve the coincidence of the combined light, reduce the color shift, and at the same time, it also homogenizes the light beam through a larger angle of diffusion, thereby reducing the speckle effect of the laser projection equipment and improving the display effect of the projection screen of the laser projection equipment.

Optionally, the orthographic projection area of the first lens 1041 on a plane perpendicular to its optical axis is greater than the orthographic projection area of the second lens 1042 on the plane, that is, the size of the first lens 1041 is larger than that of the second lens 1042 , the aperture of the first lens 1041 is larger than the aperture of the second lens 1042 . The light spot formed by the light on the second lens 1042 can be smaller than the light spot formed by the light on the first lens 1041, so the size of the first lens 1041 can be made larger than the size of the second lens 1042, avoiding setting a larger second lens 1042 This results in a waste of convex lenses.

Optionally, the light incident center of the first diffuser 105 may coincide with the focal points of the first lens 1041 and the second lens 1042 . The first diffusing portion 105 may be perpendicular to the arrangement direction of the first lens 1041 and the second lens 1042 (ie, the x direction in FIG. 7 ), that is, the first diffusing portion 105 is located between the first lens 1041 and the second lens 1042 . At the focal plane where the lenses 1042 coincide. Optionally, the diffusion angle of the first diffusion part 105 ranges from 5 degrees to 16 degrees.

The laser 120 in this embodiment of the present application may emit laser light of at least two colors, or may also emit laser light of three colors. When the light emitted by the light source is a laser, the laser projection equipment will produce speckle effect, so it is necessary to set a diffuser to reduce the speckle effect. Optionally, the at least two colors of laser light may include: laser light with a first divergence angle and laser light with a second divergence angle, where the first divergence angle is greater than the second divergence angle. Exemplarily, the at least two color lasers may include: red laser, green laser and blue laser, wherein the divergence angle of the red laser is greater than the divergence angle of the blue laser and the green laser, so the red laser is the laser with the first divergence angle , the green laser and the blue laser are the lasers of the second divergence angle.

Based on the laser 120 , as shown in FIG. 4 , in the embodiment of the present application, the first diffusion part 105 may include a first diffusion region and a second diffusion region, and the diffusion angle of the first diffusion region is smaller than the diffusion angle of the second diffusion region. The laser light with the first divergence angle may be directed toward the first diffusion area, and the laser light with the second divergence angle may be directed toward the second diffusion area. Because the divergence angle of the laser light directed to the first diffusion region is greater than the divergence angle of the laser light directed to the second diffusion region, and the diffusion angle of the first diffusion region is smaller than that of the second diffusion region. In this way, the difference between the laser beams with different divergence angles emitted from the first diffusing part 105 can be reduced, the coincidence degree of the combined light spots of the multi-color laser beams can be improved, the boundary phenomenon of the combined light spots can be avoided, and it can also be used for The uniformity of the projected laser light reduces the speckle effect and further improves the display effect of the projected image.

In this embodiment of the present application, the homogenizing component 101 may include a fly-eye lens. The homogenization effect of the fly-eye lens on the light is better, and the homogenization effect of the fly-eye lens on the light is independent of its thickness, so the use of a thinner fly-eye lens can ensure a better homogenization effect on the light, which further ensures the laser projection equipment. miniaturization.

Optionally, the fly-eye lens has a better homogenization effect on parallel light, and the light radiating toward the fly-eye lens may be parallel light or approximately parallel light. Optionally, the optical axes of the first lens 1041, the second lens 1042 and the fly-eye lens may be collinear. It should be noted that, in the embodiment of the present application, a beam reduction system is arranged between the light source and the fly-eye lens to reduce the light spot incident to the fly-eye lens, so that the size of the fly-eye lens can be smaller. Since the cost of the fly-eye lens is relatively high, the cost of the fly-eye lens can be saved, thereby saving the manufacturing cost of the laser projection equipment.

Please continue to refer to FIG. 7 , the fly-eye lens may include a plurality of lens units Y. As shown in FIG. For example, the plurality of lens units Y may be arranged in an array. The fly-eye lens can satisfy at least one of the following:

The orthographic projection area of the fly-eye lens on the plane perpendicular to the optical axis of the fly-eye lens ranges from 144 square millimeters to 265 square millimeters;

The orthographic projection of the fly-eye lens on a plane perpendicular to the optical axis of the fly-eye lens is a rectangle, and the aspect ratio of the rectangle ranges from 1.6 to 2;

The maximum distance range of the two ends of the lens unit Y in the direction perpendicular to the optical axis is 0.5 mm to 1.5 mm;

And, the light transmittance of the fly's eye lens ranges from 98% to 99%.

It should be noted that FIG. 7 only shows six lens units Y in the fly-eye lens. Optionally, the number of the lens units Y in the fly-eye lens can be set according to the shape and size of the lens unit Y and the size of the fly-eye lens. For example, the number of lens units Y in the fly-eye lens may also be 10, 20, 50 or even more, which is not limited in the embodiment of the present application.

For example, the orthographic projection of the fly-eye lens on a plane perpendicular to the optical axis of the fly-eye lens (that is, a plane perpendicular to the x-direction) can be a quadrilateral. If the quadrilateral is a square, the side length of the square can be 12 mm. ~ 25 mm. Optionally, the orthographic projection of the fly-eye lens on the plane may also be in other shapes, such as a rectangle, a circle, or an ellipse, which is not limited in this embodiment of the present application.

For another example, the orthographic projection of the lens unit Y on a plane perpendicular to the optical axis of the fly-eye lens may be a circle, an ellipse, a quadrangle, a hexagon, or other shapes. If the orthographic projection of the lens unit Y on the plane is a circle, the distance between the two ends of the lens unit Y in the direction perpendicular to the optical axis is the diameter of the circle. If the orthographic projection of the lens unit Y on the plane is an ellipse, the maximum distance between the two ends of the lens unit Y in the direction perpendicular to the optical axis is the long axis of the ellipse. If the orthographic projection of the lens unit Y on the plane is a rectangle, the maximum distance between the two ends of the lens unit Y in the direction perpendicular to the optical axis is the length of the rectangle. If the orthographic projection of the lens unit Y on the plane is a hexagon, the maximum distance between the two ends of the lens unit Y in the direction perpendicular to the optical axis is the length of the longest diagonal of the rectangle.

Since the light spot on the fly-eye lens has an object-image relationship with the light spot on the light valve 103, the aspect ratio of the light spot on the fly-eye lens is the same as that of the light spot at the light valve 103, so the fly-eye lens can be designed according to the light valve 103. . For example, the aspect ratio of the orthographic projection of the fly-eye lens on a plane perpendicular to its optical axis is the same as the aspect ratio of the light valve 103 , for example, the aspect ratio ranges from 1.6 to 2.

In the related art, a light pipe is used as a light homogenizing component, the loss of light in the process of transmission in the light pipe is relatively high, and the light transmittance of the light pipe is relatively low. In addition, the light guide is in the shape of a long strip, the size of the light entrance of the light guide is small, and the light incident angle of the light guide is small. For example, the center of the light entrance of the light pipe can be located on the optical axis of the condensing lens, and the light can enter the light pipe only when the angle between the light emitted by the condensing lens and the optical axis of the condensing lens is within the range of the incident angle of the light pipe. . Usually, the incident light angle of the light pipe is less than 23 degrees, and the light emitted by the converging lens contains more light rays with an angle greater than 23 degrees from the optical axis. These light rays will be wasted, so more light emitted by the light source is wasted. The utilization of the emitted light is low.

However, in the embodiment of the present application, the light transmittance of the fly-eye lens can reach 98%-99%, and the light transmittance of the fly-eye lens is greater than that of the light pipe, so the loss of light in the uniform light process can be reduced. In addition, the size of the fly-eye lens can be larger than the size of the light entrance of the light guide, and the light emitted by the light source can be more directed to the fly-eye lens, and then uniformly emitted by the fly-eye lens, so the utilization rate of the light emitted by the light source is high, and the light loss Less, the light efficiency of the optomechanical is higher.

FIG. 8 is a schematic structural diagram of another laser projection device provided by an embodiment of the present application. As shown in FIG. 8 , the laser projection apparatus 00 may further include: a second diffusing part 106 , the second diffusing part 106 is located between the second lens 1042 and the light homogenizing member 101 . Optionally, the diffusion angle of the second diffusion part 106 may be smaller than the diffusion angle of the first diffusion part 105 . For example, the range of the diffusion angle of the second diffusion part 106 is 1 degree to 6 degrees. Optionally, the second diffusion part 106 can be fixedly arranged. Optionally, the second diffusing part 106 may also be located in the optical path before the light emitted by the laser 120 enters the first lens 1041, for example, the second diffusing part 106 may also be located between the laser 120 and the first lens 1041, which is implemented in this application. The example does not illustrate this approach.

In the embodiment of the present application, on the basis of disposing the first diffusing part 105 , a second diffusing part 106 may be further disposed to further assist the first diffusing part 105 to diffuse and homogenize light, and further reduce the speckle effect of the laser projection device. In addition, since the second diffusing portion 106 is close to the light homogenizing member 101, and the light passing through the second diffusing portion 106 is transmitted according to its exit angle, the diffusing angle of the second diffusing portion 106 is made smaller, thereby avoiding passing through the second diffusing portion 106. Due to the large divergence angle, the light of 106 is projected to the outside of the homogenizing member 101, resulting in the waste of light. In addition, due to the constriction of the light by the lens group 104, the light spot directed to the second diffuser 106 is small, and the area of the second diffuser 106 can also be small, thereby further reducing the manufacturing cost of the optical machine.

Optionally, please continue to refer to FIG. 8 , the laser projection apparatus 00 may further include: a first driving structure 107 and/or a second driving structure 108 . FIG. 8 illustrates by taking the laser projection apparatus including the first driving structure 107 and the second driving structure 108 as an example for illustration. The first driving structure 107 is used to drive the diffuser (eg, the first diffuser 105 and the second diffuser 106 ) between the light source and the homogenizing member 101 to move in a target direction, and the target direction intersects the light source and the homogenizing member 101 The arrangement direction (that is, the x-direction). For example, the target direction is perpendicular to the x direction, for example, the target direction may be the y direction, or the target direction is perpendicular to both the x direction and the y direction (ie, the direction perpendicular to the paper surface). The second driving structure 108 is used for driving the diffuser to rotate about an axial direction parallel to the arrangement direction of the light source and the light homogenizing member 101 (ie, the x-direction).

The diffusion sheet includes microstructures with different diffusion angles arranged according to a certain rule. For example, the microstructures may be structures similar to micro-convex lenses. When the diffuser is in motion, the light can be directed to different positions of the diffuser at different times, so that the divergence angles of the light at different times are different, and the speckles of different shapes and positions formed by the laser projection equipment according to the projection of the light can be scattered and superimposed, and then Users can not see obvious speckle, which plays a better role in eliminating speckle.

It should be noted that, in the first diffusion part 105 and the second diffusion part 106, only one diffusion sheet can be driven by the at least one driving structure, or the two diffusion sheets can also be driven by the at least one driving structure. When moving downward, the two diffusion sheets may move in the same manner or in different manners, which are not limited in the embodiment of the present application. By way of example, FIG. 8 illustrates the movement of the first diffusion part 105 under the driving of the first driving structure 107 and the movement of the second diffusion part 106 under the driving of the second driving structure 108 as an example.

Optionally, please continue to refer to FIG. 7 and FIG. 8 , the laser projection apparatus 00 may further include: an illumination mirror group 102 located between the light homogenizing component 101 and the light valve 103 . The illumination lens group 102 may include: a third convex lens T3, a reflection sheet F, a fourth convex lens T4 and a total internal reflection prism L. The light emitted by the homogenizing member 101 can be directed to the reflection sheet F through the third convex lens T3, the reflection sheet F can reflect the incident light to the fourth convex lens T4, and the fourth convex lens T4 can converge the incident light to the total internal reflection prism L. , the total internal reflection prism L reflects the incident light to the light valve 103 . It should be noted that, for the introduction of the illuminating mirror group 102, reference may be made to the related introduction to the illuminating mirror group 0023 in FIG. 1 .

It should be noted that, in the related art, the light emitted by the light guide needs to pass through at least two lenses before being directed to the reflection sheet. In the embodiment of the present application, the beam reduction system composed of the first lens and the second lens can emit parallel light, and the light emitted by the fly-eye lens has a high degree of collimation, so it can only pass through a light-receiving convex lens (that is, the first Tri-convex lens) narrows the divergence angle of the light, so that the light that meets the modulation requirements of the light valve can be obtained, and then the light is directed to the reflective sheet, the fourth convex lens and the light valve in sequence. Since the number of light-receiving lenses between the homogenizing component and the reflective sheet is reduced in the embodiments of the present application, the volume of the laser projection device can be further ensured to be small, and the miniaturization of the laser projection device is facilitated.

FIG. 9 is a schematic diagram of a partial structure of a laser projection device provided by an embodiment of the present application, and only a partial structure and a light valve in the illumination mirror group are illustrated. The illumination mirror group 102 and the light valve 103 shown in FIG. 9 may be the left side view of the illumination mirror group 102 and the light valve 103 in FIG. 7 or FIG. 8 , and the illumination mirror group 102 and the light valve 103 in FIG. 7 or FIG. The top view of the illumination mirror group 102 and the light valve 103 is shown rotated 90 degrees clockwise. As shown in FIG. 9 , the total internal reflection prism L in the illumination mirror group 102 may include two triangular prisms (respectively a first prism L1 and a second prism L2 ), and the second prism L2 may be located at the first prism L1 away from the light valve 103 side. There may be an air gap between the two surfaces of the first prism L1 and the second prism L2 that are close to each other, and then the two triangular prisms may form a total internal reflection prism to ensure that the light incident on the first prism L1 can be close to the second prism L1. Total reflection occurs on the side surface of the second prism L2 , and then the first prism L1 is emitted to the light valve 103 . The light valve 103 can reflect the light, so that the light passes through the first prism L1 and the second prism L2 in sequence and then goes toward the lens. Optionally, the light path of the light in the illuminating mirror group 102 may also be referred to as an illuminating light path.

Optionally, the light valve in the embodiment of the present application may be adapted and modified according to the different projection architectures of the laser projection device. For example, the light valve may be a liquid crystal on silicon (Liquid Crystal on Silicon, LCOS), a liquid crystal display (Liquid Crystal Display, LCD) or a digital micromirror device (Digital Micromirror Device, DMD). The embodiments of the present application illustrate that the laser projection device adopts a digital light processing (Digital Light Processing, DLP) architecture, and the light valve is a DMD as an example for explanation. Exemplarily, the DMD includes a plurality of tiny reflective sheets (not shown in the figure), each reflective sheet can be regarded as a pixel, and the light reflected by each reflective sheet can be used to display a pixel in the projection image. The reflective sheet can be in two states. In the first state, the reflective sheet can reflect the incident light to the lens, and in the second state, the reflective sheet can reflect the incident light to the outside of the lens, so as to realize the light and dark display of the pixels. For example, when the reflection sheet is rotated by plus 17 degrees or plus 12 degrees from the initial state, the reflection sheet can be in the first state, and when the reflection sheet is rotated by minus 17 degrees or minus 12 degrees from the initial state, the reflection sheet can be in the second state. For example, if the light valve shown in FIG. 8 represents a reflection sheet, the reflection sheet may be in the first state at this time, and the initial state of the reflection sheet may be that the reflection sheet is parallel to the side surface of the first prism L1 that is close to it. status. For example, the angle rotated clockwise from the initial state is a positive angle, and the angle rotated counterclockwise from the initial state is a negative angle. In this way, the state of each reflection sheet in the DMD can be adjusted, so that the laser projection equipment can project corresponding projection images.

To sum up, in the laser projection device provided by the above embodiments of the present application, the first lens, the first diffuser, the second lens and the light homogenizing component are sequentially arranged on the optical path between the light source and the light valve. Preferably, the focal points of the first lens and the second lens coincide, and the spot area on the first lens is larger than the spot area on the second lens, and the first lens and the second lens can condense the light emitted by the light source to ensure that the light More light is directed to the uniform light component to form a projection screen, ensuring a high utilization rate of light. And since the first diffuser is located at the coincident focal point, on the one hand, according to the principle of beam convergence imaging, the light at the focal point (convergence imaging point) can in principle be regarded as a point light source exiting the lens at any beam angle, and can be regarded as a point light source. The lens is collimated into a parallel beam. Therefore, the first diffuser can be set with a larger divergence angle, which can diffuse the incident laser beam to a greater extent, reduce the difference in the degree of divergence of laser beams of different colors, and make the laser beam The homogenization effect is good, and the laser beam diffused by a large angle can still be condensed into a collimated state by the second lens after it is emitted to the second lens.

Due to the large-angle diffusion, the homogenization effect of the laser beam is improved, and it is also beneficial to improve the speckle effect.

On the other hand, the spot size of the laser beam collimated by the second lens is reduced, so that the beam reduction of the laser beam is realized, thereby facilitating the utilization of the rear optical lens. In the above technical solution, there is no need to additionally set a special optical path position for the first diffuser, but it is located between the original two lenses, which can reduce the beam, reduce the divergence difference of laser beams of different colors, and dissipate the speckle. Multiple functions without increasing the length of the optical path, which is beneficial to the miniaturization of the light source structure.

FIG. 10 is a schematic structural diagram of another optical engine of a laser projection device provided by an embodiment of the present application. FIG. 10 may be an overall appearance diagram of an optical engine of a laser projection device, and the appearance diagram may be an overall appearance diagram of an optical engine of a laser projection device of any optional structure in the foregoing embodiments. As shown in FIG. 10 , the laser projection device includes: a light source 10 , an optical machine 20 and a lens 30 . The light source 10 is used to emit light to the optical machine 20, and the optical machine 20 is used to modulate the incident light and then send it to the lens 30, and the lens 30 is used to project the incident light. For example, the light source 10 may include any embodiment of the laser light source which may be any of the above-mentioned Figs. 3-1 to 3-4 and their modifications. Alternatively, the optical engine optical path may be the above-mentioned laser projection optical path system shown in FIG. 7 or 8 and its improved type, and has the beneficial effects of the above-mentioned laser light source or laser projection optical path, which will not be repeated here.

The term "and/or" in this application is only an association relationship to describe associated objects, which means that there can be three kinds of relationships, for example, A and/or B, which can mean that A exists alone, A and B exist at the same time, independently There are three cases of B. In addition, the character "/" in this document generally indicates that the related objects are an "or" relationship. In this application, the term "at least one of A, B and C" means that seven relationships can exist, which can mean: A alone exists, B alone exists, C alone exists, A and B exist simultaneously, A and C exist simultaneously, and There are C and B, and there are seven cases of A, B, and C at the same time. In the embodiments of the present application, the terms "first" and "second" are only used for description purposes, and cannot be understood as indicating or implying relative importance. The term "plurality" refers to two or more, unless expressly limited otherwise.

The above descriptions are only 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 principles of the present application shall be included in the protection of the present application. within the range.

Claims (16)

1. A laser light source, characterized in that, comprising:

   Lasers, at least emitting blue and red lasers;

   a first lens, a first diffuser and a second lens arranged in sequence along the light emitting direction of the light source, the first lens is used for converging the blue laser and the red laser to the first diffuser;

   The first diffusing part is used for expanding the divergence angles of at least the blue laser and the red laser and then shooting toward the second lens;

   The second lens is used for converging at least the blue laser light and the red laser light in a diverging state,

   The focal point of the second lens is located between the first lens and the second lens, the first diffuser is located at the focal plane of the second lens, and the light spot emitted by the second lens The size is smaller than the size of the light spot incident on the incident side of the first lens.
2. The laser light source according to claim 1, wherein,

   The range of the diffusion angle of the first diffusion portion is 5 degrees to 16 degrees.
3. The laser light source according to claim 1, wherein,

   Both the first lens and the second lens are convex lenses, and the focal points of the two are coincident.
4. The laser light source according to claim 1, wherein,

   The first diffuser is a moving diffuser.
5. The laser light source according to claim 1, wherein,

   The optical axes of the first lens and the second lens are coincident, and the ratio of the spot area on the incident side of the first lens to the spot area on the exit side of the second lens ranges from 1.5 to 3.
6. The laser light source according to claim 1, wherein,

   The focal length of the first lens is greater than the focal length of the second lens.
7. The laser light source according to claim 1, wherein,

   The laser also emits green laser light.
8. The laser light source according to any one of claims 1-7, characterized in that,

   A second diffuser is also arranged between the laser and the first lens,

   Alternatively, a second diffuser is further provided behind the second lens.
9. The laser light source according to claim 8, wherein:

   The second diffuser is a fixed diffuser.
10. The laser light source according to claim 8, wherein:

    The divergence angle of the second diffuser is smaller than the divergence angle of the first diffuser.
11. The laser light source according to any one of claims 1-7, characterized in that,

    The first diffusion part has at least two subsections, wherein the red laser light is transmitted through the first subsection, and the blue laser light is transmitted through the second subsection, and the diffusion angle of the first subsection is smaller than the diffusion angle of the second subsection.
12. The laser light source according to claim 7, wherein,

    The laser is an MCL-type laser, and the MCL-type lasers are at least three groups, respectively emitting red laser, blue laser, and green laser;

    The MCL lasers are a group, including multiple light-emitting chips arranged in rows and columns, respectively emitting red lasers, blue lasers, and green lasers.
13. A laser projection device, characterized in that it includes:

    A laser light source, a light valve and a lens, the laser light source is used to emit light to the light valve, the light valve is used to modulate the incident light and then shoot it towards the lens, and the lens is used to transmit the incident light to the lens. Projection; the laser light source is the laser light source described in any one of claims 1-12.
14. The laser projection device according to claim 13, wherein the laser projection device further comprises: a uniform light component;

    The light emitted by the laser light source is directed to the light homogenizing component, and the light homogenizing component is used for homogenizing the incident light and then emitting it to the light valve through the illuminating mirror group.
15. The laser projection device according to claim 14, wherein the uniform light component comprises a fly-eye lens,

    The fly-eye lens satisfies at least one of the following:

    The orthographic projection area of the fly-eye lens on a plane perpendicular to the optical axis of the fly-eye lens ranges from 144 square millimeters to 265 square millimeters;

    The orthographic projection of the fly-eye lens on a plane perpendicular to the optical axis of the fly-eye lens is a rectangle, and the aspect ratio of the rectangle ranges from 1.6 to 2;

    And, the maximum distance of the two ends of the lens unit in the direction perpendicular to the optical axis ranges from 0.5 mm to 1.5 mm.
16. The laser projection apparatus according to claim 13, wherein,

    The illuminating mirror group includes a third convex lens, a reflection sheet, a fourth convex lens and a total internal reflection prism, and the light emitted by the uniform light component is directed to the reflection sheet through the third convex lens, and the reflection sheet is used to convert the light into the reflection sheet. The incident light is reflected to the fourth convex lens, and the fourth convex lens is used for condensing the incident light to the total internal reflection prism, and the total internal reflection prism is used for reflecting the incident light to the light valve.

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