Laser light source device and projection device

Abstract

The present application discloses a laser light source device, belonging to the field of laser display. The laser light source device includes: a laser array, an optical conduction component, and a fly-eye lens. The fly-eye lens includes a plurality of rectangular lenses arranged in an array. The fast axis direction of the laser is parallel to the short side of the rectangular lens in the fly-eye lens, and the slow axis direction of the laser is parallel to the long side of the rectangular lens in the fly-eye lens. Moreover, the sine value of the divergence angle of the fast axis of the laser is greater than the sine value of the aperture angle of the long side of the rectangular lens, and the sine value of the divergence angle of the slow axis of the laser is greater than the sine value of the aperture angle of the short side of the rectangular lens. Associating the parameters of the laser with those of the fly-eye lens facilitates the realization of the light homogenization function through the fly-eye lens. Compared with an optical duct, the fly-eye lens has a smaller size in the optical path direction, and thus the size of the laser light source device is also smaller. This solves the problem of the excessively large volume of the laser light source device in the related art and achieves the effect of reducing the volume of the laser light source device.

Description

Technical Field

[0001] This application relates to the field of laser display, and particularly to a laser light source device and a projection device. Background Art

[0002] With the continuous pursuit of picture colors by people, laser projection with advantages such as a large imaging picture, high spectral brightness, and a wide display color gamut has been developed. Among them, a three-color semiconductor laser is used as a laser light source and applied to laser projection technology.

[0003] Currently, there is a laser light source device, which includes a laser array, an optical conduction component, and an optical duct arranged in sequence along the optical path. The laser array emits green, blue, and red light. The three-color light is combined by the optical conduction component, and then is homogenized by the optical duct. The homogenized laser is emitted from one end of the optical duct.

[0004] However, in the above laser light source device, the path of the laser optical path is long, resulting in a large volume of the laser light source device. Summary of the Invention

[0005] An embodiment of this application provides a laser light source device, and the technical solution is as follows:

[0006] According to the first aspect of this application, a laser light source device is provided. The device includes a laser array, an optical conduction component, and a compound eye lens arranged in sequence along the optical path direction. The compound eye lens includes a plurality of rectangular lenses arranged in an array;

[0007] The laser array includes a plurality of lasers arranged in an array. The fast axis direction of the laser is parallel to the short side of the rectangular lens in the compound eye lens, and the slow axis direction of the laser is parallel to the long side of the rectangular lens in the compound eye lens. Moreover, the sine value of the divergence angle of the fast axis of the laser is greater than the sine value of the aperture angle of the long side of the rectangular lens, and the sine value of the divergence angle of the slow axis of the laser is greater than the sine value of the aperture angle of the short side of the rectangular lens.

[0008] Optionally, the laser array includes a plurality of lasers, the compound eye lens includes a plurality of the rectangular lenses arranged in an array, and the spot area of the laser is greater than the area of the rectangular lens.

[0009] Optionally, the spot area of the laser is greater than three times the area of the rectangular lens.

[0010] Optionally, the sine value of the divergence angle of the fast axis of the laser is greater than the sine value of the divergence angle of the slow axis of the laser.

[0011] Optionally, the optical conduction component includes a stepped mirror, and the stepped mirror includes a reflecting mirror and a dichroic sheet.

[0012] Optionally, the laser light source device further includes a collimating mirror, and the collimating mirror is located between the laser array and the light conduction component.

[0013] Optionally, the laser light source device further includes a diffusion component, and the diffusion component is located between the light conduction component and the fly-eye lens. The diffusion component includes a diffusion wheel or a diffusion sheet.

[0014] Optionally, the laser light source device further includes a beam reduction system, and the beam reduction system is located between the light conduction system and the fly-eye lens.

[0015] Optionally, the laser light source device further includes the diffusion component and the beam reduction system.

[0016] According to a second aspect of the present application, a projection device is provided. The projection device includes any one of the laser light source devices described above.

[0017] The beneficial effects brought by the technical solution provided in the embodiments of the present application at least include:

[0018] A laser light source device and a projection device are provided. The laser light source device can be used in a projection device. The laser light source device includes a laser array, a light conduction component, and a fly-eye lens. The laser array includes a plurality of lasers arranged in an array. The fly-eye lens includes a plurality of rectangular lenses. The sine value of the divergence angle of the fast axis of the laser is greater than the sine value of the aperture angle of the long side of the rectangular lens, and the sine value of the divergence angle of the slow axis of the laser is greater than the sine value of the aperture angle of the short side of the rectangular lens. In this way, the parameters of the laser are associated with the parameters of the fly-eye lens, which facilitates the realization of the uniform light function through the fly-eye lens. And compared with the light guide tube, since the size of the fly-eye lens in the optical path direction is smaller, the size of the laser light source device will also be smaller. This solves the problem of the too large volume of the laser light source device in the related art and achieves the effect of reducing the volume of the laser light source device. Description of the Drawings

[0019] 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.

[0020] Figure 1 is a schematic structural diagram of a laser light source device provided by an embodiment of the present application;

[0021] Figure 2 is Figure 1 a schematic structural diagram of the laser array of the laser light source device shown in the figure;

[0022] Figure 3 is Figure 1 A schematic structural diagram of the fly-eye lens of the laser light source device shown;

[0023] Figure 4 An optical path diagram of the laser light source device provided by an embodiment of the present application;

[0024] Figure 5 is Figure 1 A schematic structural diagram of a beam reducing system in the laser light source device shown;

[0025] Figure 6 is Figure 1 A schematic structural diagram of a fly-eye lens in the laser light source device shown;

[0026] Figure 7 A schematic structural diagram of a projection device shown in an embodiment of the present application.

[0027] Through the above-mentioned drawings, the specific embodiments of the present application have been shown, and there will be more detailed descriptions hereinafter. 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. Specific Embodiments

[0028] To make the purpose, 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 drawings.

[0029] Figure 1 A schematic structural diagram of a laser light source device provided by an embodiment of the present application, as Figure 1 shown, the laser light source device 1 includes a laser array 11, an optical conduction component 12, and a fly-eye lens 13 arranged in sequence along the optical path direction. The fly-eye lens 13 includes a plurality of rectangular lenses arranged in an array. The laser array 11 emits a beam, and the optical conduction component 12 is used to receive the beam emitted by the laser array 11 and direct it to the fly-eye lens 13.

[0030] The laser array 11 includes a plurality of lasers arranged in an array. The fast axis direction of the laser is parallel to the short side of the rectangular lens in the fly-eye lens 13, and the slow axis direction of the laser is parallel to the long side of the rectangular lens in the fly-eye lens 13. Moreover, the sine value sinα1 of the divergence angle of the fast axis of the laser is greater than the sine value sinβ1 of the aperture angle β1 of the long side of the rectangular lens, that is, sinα1 > sinβ1; the sine value sinα2 of the divergence angle α2 of the slow axis of the laser is greater than the sine value sinβ2 of the aperture angle β2 of the short side of the rectangular lens, that is, sinα2 > sinβ2.

[0031] Among them, the direction of the optical vector with a slow propagation speed in the laser is called the slow axis of the laser, and the direction of the optical vector with a fast propagation speed in the laser is called the fast axis of the laser. Figure 2 is Figure 1 a schematic structural diagram of the laser array of the laser light source device shown, as Figure 2 shown, in the laser array of the laser light source device provided in the embodiment of the present application, the fast axis direction of the laser is f1, and the slow axis direction is f2.

[0032] In addition, the divergence angle of the laser is used to measure the speed at which the light beam diverges outward from the beam waist (the beam waist refers to the position where the beam radius is the smallest in the beam propagation direction, and the beam radius at this position is called the beam waist radius). The divergence angle of the laser can be measured by measuring the beam defocusing degree, that is, by using a beam analyzer to measure the beam radius at different positions, and then obtaining the divergence angle of the laser.

[0033] Figure 3 is Figure 1 a schematic structural diagram of the fly-eye lens of the laser light source device shown, as Figure 3 shown, the fly-eye lens 13 includes a plurality of rectangular lenses 131 arranged in an array.

[0034] The fly-eye lens divides the light beam into N (the value of N is the number of rectangular lenses in the fly-eye lens) channels through each rectangular lens, and the light beam in each channel independently illuminates the entire object surface, that is, the illumination of the object surface is the superposition of the illumination of each channel, so the uniformity of the illuminated object surface is greatly improved.

[0035] In the application of the fly-eye lens, two columns of fly-eye lens arrays are arranged in parallel. The focal points of the rectangular lenses in the first column of fly-eye lens arrays coincide with the centers of the corresponding rectangular lenses in the second column of fly-eye lens arrays, and the optical axes of the two columns of fly-eye lenses are parallel to each other, so that the spot of the input laser beam can be segmented, and then the segmented spots are accumulated through the subsequent focusing lens, so as to realize the homogenization of the light beam and the optimization of the spot.

[0036] In addition, the volume of the fly-eye lens as a light homogenizing device is small, so the volume of the laser light source device can be correspondingly reduced, and further the volume of the projection device using the laser light source device can be reduced, making the overall projection device thinner, lighter and more beautiful, and the user experience is better.

[0037] In summary, the embodiment of the present application provides a laser light source device, which includes a laser array, an optical conduction component, and a fly-eye lens. The laser array includes a plurality of lasers arranged in an array, and the fly-eye lens includes a plurality of rectangular lenses. The sine value of the divergence angle of the fast axis of the laser is greater than the sine value of the aperture angle of the long side of the rectangular lens, and the sine value of the divergence angle of the slow axis is greater than the sine value of the aperture angle of the short side of the rectangular lens. In this way, the parameters of the laser are associated with the parameters of the fly-eye lens, which facilitates the realization of the light homogenization function through the fly-eye lens. Moreover, compared with the light guide tube, since the size of the fly-eye lens in the optical path direction is smaller, the size of the laser light source device is also smaller. This solves the problem of the too large volume of the laser light source device in the related art and achieves the effect of reducing the volume of the laser light source device.

[0038] Optionally, please refer to Figure 2 and Figure 3 , the laser array 11 includes a plurality of lasers 111, and the fly-eye lens 13 includes a plurality of rectangular lenses 131 arranged in an array. The spot area of the laser 111 is larger than the area of the rectangular lens 131. As Figure 3 shown, the rectangular lenses 131 in the fly-eye lens 13 are evenly arranged, and each rectangular lens 131 has a long side a and a short side b. Therefore, the area S1 of the rectangular lens 131 = a·b; at the same time, in the embodiment of the present application, the spot area S2 of the laser 111 is larger than the area S1 of the rectangular lens 131, that is, S2 > S1. With such a structure, the spot of the laser passes through the rectangular lenses in the plurality of fly-eye lenses, so that the spot can be divided as many times as possible to meet the light homogenization requirements of the laser beam.

[0039] Optionally, the spot area S2 of the laser is larger than three times the area S1 of the rectangular lens, that is, S2 > 3S1. With such a structure, the spot of the laser can pass through at least three rectangular lenses, so that the spot of the laser is divided into multiple parts by the rectangular lenses in the fly-eye lens, and then the divided spots are superimposed by the subsequent focusing lens to realize the homogenization of the beam.

[0040] Optionally, the sine value sinα1 of the divergence angle of the fast axis of the laser is greater than the sine value sinα2 of the divergence angle of the slow axis of the laser. Among them, the range of the divergence angle of the fast axis of the beam output by the array laser can be 40 degrees to 90 degrees, and the divergence angle of the slow axis can be 10 degrees.

[0041] In addition, please refer to Figure 2, the laser array 11 includes lasers 111 for emitting three - color lasers, namely a red laser 111a for emitting red laser, a blue laser 111b for emitting blue laser, and a green laser 111c for emitting green laser. The red laser emitted by the red laser 111a can have a wavelength ranging from 638 nm to 650 nm. The wavelength of the laser refers to the wavelength of the output laser of the laser. The laser wavelength range of the blue laser 111b can be from 445 nm to 450 nm, and the laser wavelength range of the green laser 111c can be from 532 nm to 556 nm.

[0042] Exemplarily, as Figure 2 shown, the laser 111 includes two groups of red lasers 111a, one group of blue lasers 111b, and one group of green lasers 111c. In one embodiment, the arrangement of the lasers within the laser is such that seven lasers are arranged in a row, and a total of four rows are arranged. The first row is arranged with green lasers 111c, the second row is arranged with blue lasers 111b, and the third row and the fourth row are arranged with red lasers 111a.

[0043] Meanwhile, the fast - axis direction f1 of the laser 111 is parallel to the column direction of the laser 111, and the slow - axis direction f2 is parallel to the row direction of the laser 111.

[0044] In addition, the red laser, blue laser, and green laser emitted by the red laser 111a, blue laser 111b, and green laser 111c are called primary color lights, and their English representations are R (Red), B (Blue), and G (Green) respectively. All colors in nature can be obtained by changing the frequency and intensity of the primary color lights and then combining them. In addition, when the red laser, blue laser, and green laser are mixed in equal proportions, white light can be formed.

[0045] Optionally, the sine value sinβ1 of the aperture angle β1 of the long side of the rectangular lens is greater than the sine value sinβ2 of the aperture angle β2 of the short side of the rectangular lens.

[0046] Optionally, please refer to Figure 4 , Figure 4 is the optical path diagram of the laser light source device provided by the embodiment of the present application. The light - conducting component 12 includes a stepped mirror 121. The stepped mirror 121 includes a reflector 1211 and a dichroic sheet 1212. The reflector 1211 is located between the green laser 111c and the fly - eye lens 13. The reflector 1211 is used to turn the optical path and direct the green laser emitted by the green laser 111c to the dichroic sheet 1212.

[0047] In the embodiment of the present application, the dichroic sheet 1212 includes a first dichroic sheet 1212a and a second dichroic sheet 1212b, as Figure 4As shown, the first dichroic sheet 1212a is located between the blue laser 111b and the fly-eye lens 13, and the second dichroic sheet 1212b is located between the two groups of red lasers 111a and the fly-eye lens 13.

[0048] Among them, the dichroic sheet, also known as a light combining mirror, is a color filter that can selectively transmit a certain color of light and reflect other colors of light. The dichroic sheet has a high transmittance for the transmitted light (the transmittance is as high as 97%) and a high reflection efficiency for the reflected light (the reflection efficiency is greater than 99%), and at the same time has the advantages of small absorption, less scattering, less laser loss, and no distinction between film surfaces.

[0049] The first dichroic sheet 1212a is used to reflect the blue laser emitted by the blue laser 111b and transmit the green laser emitted by the green laser 111c; the second dichroic sheet 1212b is used to reflect the red laser emitted by the red laser 111a and transmit the blue laser and the green laser emitted by the first dichroic sheet 1212a.

[0050] In addition, as Figure 4 shown, the blue laser reflected by the first dichroic sheet 1212a and the green laser transmitted are co-directional, and this direction y is perpendicular to the laser 111 emission direction x. Similarly, the red laser reflected by the second dichroic sheet 1212b and the green laser and the blue laser transmitted are co-directional, and this direction y is perpendicular to the laser 111 emission direction x. With such a structure, the red laser, blue laser, and green laser emitted by the laser are combined by the light conduction component 12. At the same time, the light conduction component 12 also turns the laser light path, shortening the distance of the laser light path in the direction parallel to the laser 111 emission direction, making the arrangement of the components in the laser light source device relatively compact and the space utilization rate relatively high. In this way, the volume of the laser light source device can be reduced and the system weight can be reduced to meet the requirements of miniaturization of the laser light source device.

[0051] Optionally, as Figure 4 shown, the mirror 1211 in the light conduction component 12 can be placed at 45 degrees. That is, when the green laser emitted by the green laser 111c enters the mirror 1211, the incident angle is 45 degrees.

[0052] Optionally, the dichroic sheet 1212 in the laser light source device shown in the embodiments of the present application can be a 45-degree dichroic sheet, that is, the dichroic sheet is placed at a 45-degree angle with the laser 111 emission direction x.

[0053] Optionally, please refer to Figure 1, the laser light source device 1 further includes a collimating mirror 14, and the collimating mirror 14 is located between the laser array 11 and the optical conduction component 12. The laser array 11 emits a three-color light beam, and this light beam is incident on the collimating mirror 14. The collimating mirror 14 is used to collimate the laser beam in the optical path and form parallel outgoing laser light. Due to the characteristics of the laser itself, the intensity distribution of the laser beam emitted by the laser array 11 may be uneven, for example, there may be bright spots or stripes of various shapes. Through the parallel outgoing effect of the collimating mirror 14, a parallel laser beam can be formed, and then the optical path can be turned and the three-color lasers can be combined through the optical conduction component 12. With such a structure, the spatial coherence of the laser beam is reduced and laser speckle is suppressed.

[0054] Optionally, the laser light source device 1 further includes a diffusing component 15, and the diffusing component 15 is located between the optical conduction component 12 and the fly-eye lens 13. The diffusing component 15 includes a diffusing wheel or a diffusing sheet. Since the light source is a pure three-color laser light source, laser speckle phenomenon will occur (the laser speckle phenomenon refers to that the surface of an object illuminated by a laser presents a granular structure). The laser has high coherence. Therefore, when the laser is reflected from the surface of an object, the vibrations of each point on the object to the observation point are coherent, and the light field at the observation point is the superposition of coherent sub-waves emitted from each point on the rough surface. Also, because the roughness of the rough surface is greater than the laser wavelength, the phases of the sub-lasers emitted from each point of the object reaching the observation point are in a randomly distributed state, and coherent superposition generates a speckle pattern, and the intensity of the speckle pattern is randomly distributed. In the embodiment of the present application, the diffusing component 15 can be a diffusing wheel or a diffusing sheet, which is used to perform light homogenization processing on the three-color laser to reduce the uneven distribution of the laser spot energy.

[0055] When the diffusing wheel is working, it rotates along its axis at a certain frequency. The rotating diffusing wheel can generate some random phases for the laser beam in space, so as to interfere with the coherence of the laser. Thus, the phenomenon of uneven distribution of the laser spot is reduced.

[0056] Optionally, the laser light source device 1 further includes a beam reduction system 16, and the beam reduction system 16 is located between the optical conduction system 12 and the fly-eye lens 13. If the spot size of the laser emitted by the laser 111 is too large, the laser emitted by the laser 111 can be beam-reduced to improve the diffusion efficiency. Figure 5 is Figure 1 The structural schematic diagram of a beam reduction system in the shown laser light source device, as Figure 5As shown, the beam narrowing system 16 at least includes a set of lens group structures 161. The lens group structure 161 includes a concave lens 1611 and a convex lens 1612, and the optical axes of the concave lens 1611 and the convex lens 1612 coincide. Among them, the convex lens 1612 is used to receive an incident light beam whose incident direction is parallel to the optical axis of the convex lens 1612, converge the incident light beam and reflect it to the concave lens 1611; the concave lens 1611 diverges the received light beam and emits the light beam along a direction parallel to the concave lens 1611. With such a structure, the convex lens converges the light beam with a larger aperture and emits it to the concave lens, and the concave lens diverges the light beam to form an outgoing light beam with a smaller aperture, so as to achieve the effect of narrowing the light beam.

[0057] Optionally, the laser light source device 1 further includes a diffusion component 15 and a beam narrowing system 16. In one implementation, the laser light source device can include both the diffusion component 15 and the beam narrowing system 16 at the same time. Among them, the beam narrowing system 16 is located between the diffusion component 15 and the light conduction component 12.

[0058] Optionally, please refer to Figure 4 , the laser light source device 1 further includes a half-wave plate 17. The half-wave plate 17 is located between the two sets of red lasers 111a and the second dichroic sheet 1212b, and the plane of the half-wave plate 17 is perpendicular to the direction of the light beam emitted by the red laser 111a. The half-wave plate can change the polarization direction of the laser polarized light, thereby improving the light processing consistency of the projection optical system and the projection screen for the three-color laser, and further solving the color cast problems such as "color spots" or "color blocks" in the three-color laser projection picture.

[0059] Figure 6 is Figure 1 a schematic structural diagram of a fly-eye lens in the laser light source device shown. As Figure 4 and Figure 6 shown, the fly-eye lens 13 includes a first fly-eye lens 131 and a second fly-eye lens 132 arranged in parallel. The first fly-eye lens 131 is used to receive the light beam emitted by the light conduction component 12, and the second fly-eye lens 132 is used to emit the homogenized light beam. Among them, the number of rectangular lenses on the first fly-eye lens 131 and the second fly-eye lens 132 is equal and they correspond one by one.

[0060] As Figure 6As shown, the light beam vertically enters the first compound eye lens 131 along the y direction and forms a parallel light beam parallel to the optical axis. After passing through the first compound eye lens 131, the light beam is focused at the center of the second compound eye lens 132. That is, the first compound eye lens 131 forms multiple light source images from the light source for illumination. Each rectangular lens of the second compound eye lens 132 overlaps and images the corresponding rectangular lens on the first compound eye lens 131. The subsequent condenser lens focuses the light spot emitted from the second compound eye lens 132 on the display screen. With such a structure, the first row of compound eye lenses 131 divides the entire wide light beam of the light source into multiple thin light beams. Due to the mutual superposition of the thin light beams in the symmetric positions, the minute non-uniformities within each thin light beam range are compensated, so that the light energy within the entire aperture is effectively and uniformly utilized, realizing the homogenization of the light beam.

[0061] Optionally, the first compound eye lens can be integrally formed with the second compound eye lens through a substrate. Among them, the substrate material can be a glass material or other light-transmitting materials. The first compound eye lens is located on one side of the substrate, and the second compound eye lens is located on the other side of the substrate. With such a structure, it is not only convenient for installation, but also can save the space occupied by the compound eye lens, further reducing the volume of the laser light source device and making its shape more beautiful.

[0062] In summary, the embodiment of the present application provides a laser light source device, which includes a laser array, an optical conduction component, and a compound eye lens. The laser array includes multiple lasers arranged in an array, and the compound eye lens includes multiple rectangular lenses. The sine value of the divergence angle of the fast axis of the laser is greater than the sine value of the aperture angle of the long side of the rectangular lens, and the sine value of the divergence angle of the slow axis of the laser is greater than the sine value of the aperture angle of the short side of the rectangular lens. In this way, the parameters of the laser are associated with the parameters of the compound eye lens, which is convenient for realizing the function of light homogenization through the compound eye lens. And compared with the light guide tube, since the size of the compound eye lens in the optical path direction is smaller, the size of the laser light source device will also be smaller. It solves the problem of the too large volume of the laser light source device in the related art and achieves the effect of reducing the volume of the laser light source device.

[0063] In addition, the embodiment of the present application also provides a projection device. Please refer to Figure 7 , Figure 7 which is a schematic structural diagram of a projection device shown in the embodiment of the present application. The projection device may include a reflecting mirror 2, a light valve 3, a total reflection prism 4, a galvanometer 5, a lens assembly 6, a screen 7, and the laser light source device 1 provided in the above embodiment.

[0064] Among them, the laser light source device 1, the reflector 2, the light valve 3, the total reflection prism 4, the galvanometer 5 and the lens assembly 6 are arranged in sequence along the light path direction. The laser light source device 1 is used to provide an illumination light beam, the reflector 2 is used to turn the light beam provided by the laser light source device 1, the total reflection prism 4 is used to receive the light beam derived from the reflector 2 and guide it to the light valve 3, the light valve 3 is used to receive the light beam and modulate it to form an image beam, and then cooperate with the galvanometer 5 and the total reflection prism 4 to guide the light beam to the lens assembly 6, the lens assembly 6 is used to receive the image beam and correct and amplify the image beam and then project it onto the screen 7. The galvanometer 5 is located between the total reflection prism 4 and the lens assembly 6, the total reflection prism 4 is used to direct the image beam modulated by the light valve 3 to the galvanometer 5, the galvanometer 5 vibrates at a preset frequency, so that the light beams passing through the galvanometer 5 are misaligned and superimposed and enter the lens assembly 6.

[0065] Among them, the light valve (English: digital micromirror device, referred to as DMD) is a digital micromirror element that can digitally modulate light. At the same time, the light valve can include an array of multiple high-speed digital light-reflecting micromirrors, which corresponds to the light in the projected image. When these micromirrors work together with digital signals, light sources and projection lenses, the image can be truly restored.

[0066] The micro-electrodes under each micro-mirror are activated by digital signals, and the micro-electrodes push the mirror surface of the micro-mirror toward or away from the light source. When the mirror surface of the micro-mirror faces the light source (that is, the micro-mirror is in the on state), a white pixel will be reflected to the screen in the projection device through the lens assembly. When the mirror surface of the micro-mirror avoids the light source (that is, the micro-mirror is in the off state), the position of the micro-mirror pixel on the screen will appear dark. Therefore, the multiple small reflectors in the light valve correspond to one pixel one by one, and the number of reflectors determines the display resolution of the light valve. For example, for a 4K resolution light valve, the micro-mirror array arrangement can be 4096*2160.

[0067] At the same time, the opening and closing speed of the micromirror can be 5000 times / second (that is, the micromirror in the light valve can rotate thousands of times in one second). Therefore, by exchanging the opening and closing time of each micromirror, different levels of grayscale can be generated. For example: the time when the micromirror is turned on is greater than the time when it is closed, the lighter the grayscale pixel generated; the time when the micromirror is closed is greater than the time when it is turned on, the darker the grayscale pixel generated.

[0068] In addition, during the operation of the light valve, the micromirrors reflect light by rotating, and the rotation of each micromirror is controlled by a microelectrode located under each micromirror. At the same time, each micromirror reflects only one color during one rotation. For example, the micromirror projecting a purple pixel is only responsible for projecting red and blue light (the combination of red light and blue light is purple light) onto the screen, and the micromirror projecting an orange pixel is only responsible for reflecting red and green light in proportion on the screen (the proportion of red light is higher and the proportion of green light is lower). Since the opening and closing speed of the micromirror surface is fast, the light is projected onto the screen through the lens assembly, and the human visual organ mixes the rapidly flashing three-color light together. Due to the persistence of vision, a clear image can be seen on the screen.

[0069] Among them, the light valve 2 can be of 2K resolution, 3K resolution or higher resolution, and the embodiments of the present application do not limit this.

[0070] The total internal reflection (English name: total internal reflection; abbreviation: TIR) prism 4 is located between the galvanometer 5 and the light valve 3. The total internal reflection prism 4 is used to change the light beam emitted by the light valve 2 into a parallel beam to improve the smoothness of the final image formed on the screen 7. As Figure 7 shown, the laser beam emitted by the laser in the laser light source device 1 enters the total internal reflection prism 4 after the optical path is turned by the reflecting mirror 2. The total internal reflection prism 4 can direct the light beam to the light valve 3. After receiving the light beam, the light valve 3 modulates it to form an image light beam. This part of the light beam enters the total internal reflection prism 4 again, and then forms parallel light through the total internal reflection prism 4. The parallel light is incident on the galvanometer 5 and then emitted from the galvanometer 5 to the lens assembly 6, and then forms an image on the screen 7.

[0071] Among them, the reflecting mirror 2 is used to turn the path of the laser beam emitted by the laser light source device 1. Optionally, the reflecting mirror 2 can be placed at an angle of 45 degrees to the direction of the laser emission. With such a structure, the optical path of the laser emitted by the laser light source device 1 is turned by 90 degrees, which can shorten the length of the optical path in the laser emission direction and further reduce the volume of the projection device.

[0072] Among them, the total internal reflection prism 6 can be a prism with a right-angled triangle cross-section, or a prism with a right-angled triangle cross-section glued to a compensation prism. The embodiments of the present application do not limit this.

[0073] At the same time, when the total internal reflection prism is used for illumination, the total internal reflection function is realized in the illumination optical path, and the light incident on the prism can be totally reflected onto the light valve; when the total internal reflection prism is used in an ultra-short focal length lens system, the total internal reflection prism can be used as a flat glass to well control the influence of dust on the imaging quality of the system.

[0074] In addition, the galvanometer 3 may include an optical lens and a driving component. The driving component may drive the optical lens to continuously swing around a preset rotation axis, and the optical lens may accordingly change the direction of the light beam. Among them, the optical lens may be a flat glass or a reflector.

[0075] Exemplarily, when the light beam incident on the galvanometer is a parallel light beam (i.e., the incident angle of each ray in the light beam is 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, so that the offset amount from each field of view in the projection lens to the projection screen is consistent, which can ensure the high-resolution display of the visual picture. Among them, the offset amount of the field of view refers to the actual displacement distance of the field of view. Therefore, if the light beam emitted from the galvanometer is parallel light, the 2K or 3K resolution can be converted to 4K resolution through the high-frequency vibration of the galvanometer. With such a structure, the system design difficulty can be reduced.

[0076] After the galvanometer is applied, the combination of the 2K resolution light valve and the galvanometer can also achieve 4K resolution. The combination of the 4K resolution light valve and the galvanometer can also achieve 8K resolution. While improving the resolution, the overall size of the machine can also be taken into account.

[0077] Optionally, the flatness of the galvanometer is less than 3 fringes, and the irregularity is less than 1 / 2 fringe. Flatness refers to the deviation of the macroscopic concavo-convex height of the substrate relative to the ideal plane. The measured actual surface is compared with the ideal plane, and the linear distance between the two is the flatness error value; or by measuring the relative height differences of several points on the actual surface and then converting to the flatness error value expressed in linear values. The measurement method of the flatness error can refer to the related technology, and the embodiments of the present application do not limit it here. The flatness of the reflector used in the present application is less than 3 fringes, and the irregularity is less than 1 / 2 fringe. The specific flatness is not limited in the embodiments of the present application here.

[0078] In summary, the embodiments of the present application provide a projection device, which includes a light valve, a galvanometer, a lens assembly, a screen, and the laser light source device provided in Embodiment 1. The laser light source device includes a laser array, a light conduction component, and a fly-eye lens. The sine value of the divergence angle of the fast axis of the laser is greater than the sine value of the aperture angle of the long side of the rectangular lens, and the sine value of the divergence angle of the slow axis of the laser is greater than the sine value of the aperture angle of the short side of the rectangular lens. In this way, the parameters of the laser are associated with the parameters of the fly-eye lens, which is convenient to achieve the function of light homogenization through the fly-eye lens. And compared with the light guide tube, since the size of the fly-eye lens in the optical path direction is smaller, the size of the laser light source device will also be smaller, which further reduces the volume of the projection device and makes its appearance thin, light, and beautiful. It solves the problem that the volume of the laser light source device is too large in the related technology and achieves the effect of reducing the volume of the laser light source device.

[0079] In this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The term "plurality" means two or more, unless otherwise clearly defined.

[0080] The above are only optional embodiments of this application and are not intended to limit this application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of this application shall be included within the protection scope of this application.

Claims

1. A laser light source device, characterized in that, The laser light source device includes a laser array, an optical conduction component, and a fly-eye lens arranged in sequence along the optical path direction. The fly-eye lens includes a plurality of rectangular lenses arranged in an array. The laser array includes a plurality of lasers arranged in an array. The fast axis direction of the laser is parallel to the short side of the rectangular lens in the fly-eye lens, and the slow axis direction of the laser is parallel to the long side of the rectangular lens in the fly-eye lens. Moreover, the sine value of the divergence angle of the fast axis of the laser is greater than the sine value of the aperture angle of the long side of the rectangular lens, and the sine value of the divergence angle of the slow axis of the laser is greater than the sine value of the aperture angle of the short side of the rectangular lens. Among them, the laser array includes a plurality of lasers for emitting three-color lasers. The red laser, blue laser, and green laser emitted by the lasers are combined by the optical conduction component and directed to the fly-eye lens.

2. The laser light source device according to claim 1, wherein, The fly-eye lens includes a plurality of the rectangular lenses arranged in an array, and the spot area of the laser is larger than the area of the rectangular lens.

3. The laser light source device according to claim 2, wherein The spot area of the laser is larger than three times the area of the rectangular lens.

4. The laser light source device according to claim 2, characterized in that, The sine value of the divergence angle of the fast axis of the laser is greater than the sine value of the divergence angle of the slow axis of the laser.

5. The laser light source device according to claim 3, characterized in that, The optical conduction component includes a stepped mirror, and the stepped mirror includes a reflecting mirror and a dichroic sheet.

6. The laser light source device according to claim 5, characterized in that, The laser light source device further includes a collimating mirror, and the collimating mirror is located between the laser array and the optical conduction component.

7. The laser light source device according to claim 6, characterized in that, The laser light source device further includes a diffusion component, and the diffusion component is located between the optical conduction component and the fly-eye lens. The diffusion component includes a diffusion wheel or a diffusion sheet.

8. The laser light source device according to claim 7, characterized in that, The laser light source device further includes a beam reduction system, and the beam reduction system is located between the optical conduction system and the fly-eye lens.

9. The laser light source device according to claim 7, wherein, The laser light source device further includes the diffusion component and the beam reduction system.

10. A projection device, characterized in that, The projection device includes the laser light source device according to any one of claims 1-9.

Images