Lighting system and projection device

Abstract

A lighting system includes a first laser module, a first wavelength conversion element, a second laser module and a second wavelength conversion element. The first laser module emits a first laser beam. The first wavelength conversion element includes a first wavelength conversion region and a non-wavelength conversion region. The first wavelength conversion region is configured to convert the first laser beam into a first wavelength conversion beam. The second laser module emits a second laser beam. The second wavelength conversion element includes a second wavelength conversion region configured to convert the second laser beam into a second wavelength conversion beam. When an interface between the first wavelength conversion region and the non-wavelength conversion region of the first wavelength conversion element is located on a predetermined light path of the first laser beam, the first laser module is in an off state, and the second laser module is in an on state. A projection device is also provided. The lighting system and the projection device of the present application can effectively suppress color breakup and laser speckle phenomenon, and achieve good optical effect.

Description

Technical Field

[0001] This invention relates to an optical system and apparatus, and more particularly to an illumination system and projection apparatus. Background Technology

[0002] With the development of projection technology, users have increasingly higher demands for the image quality of projectors. Some projection devices use a laser light source combined with a phosphor wheel (wavelength conversion wheel) as the source of the illumination beam. However, in projection devices using a time-rotating phosphor wheel, the slow response speed of the phosphor wheel often leads to color breaking, which means that when the phosphor wheel rotates slowly, the frequency of color switching per unit time is low, causing the human eye to perceive rainbow patterns. However, if the phosphor wheel's rotation speed is increased to improve the color breaking problem, the noise generated by the phosphor wheel and its drive motor will become excessive.

[0003] Laser projectors primarily use red, green, and blue lasers as their light source. Due to their high color purity and ability to achieve high color gamut coverage, they have gradually entered the mainstream projector market. However, the high coherence of laser light sources often causes laser speckle to appear on the images projected by laser projectors.

[0004] The "Background Art" paragraph is only used to help understand the content of this invention. Therefore, the content disclosed in the "Background Art" paragraph may include some known technologies that are not known to those skilled in the art. The content disclosed in the "Background Art" paragraph does not mean that the content or the problems to be solved by one or more embodiments of this invention were known or understood by those skilled in the art prior to this application. Summary of the Invention

[0005] This invention provides a lighting system and projection device that can effectively suppress color cracking and laser speckle, and achieve good optical effects.

[0006] Other objects and advantages of the present invention can be further understood from the technical features disclosed herein.

[0007] To achieve one, some, or all of the above-mentioned objectives, or other objectives, one embodiment of the present invention provides an illumination system including a first laser module, a first wavelength conversion element, a second laser module, a second wavelength conversion element, and a light guide assembly. The first laser module emits a first laser beam. The first wavelength conversion element includes at least one first wavelength conversion region and at least one non-wavelength conversion region. The at least one first wavelength conversion region and the at least one non-wavelength conversion region are sequentially located on the optical path of the first laser beam, and the at least one first wavelength conversion region is used to convert the first laser beam into a first wavelength converted beam. The second laser module emits a second laser beam. The second wavelength conversion element includes a second wavelength conversion region located on the optical path of the second laser beam, and the second wavelength conversion region is used to convert the second laser beam into a second wavelength converted beam. When the boundary between the at least one first wavelength conversion region and the at least one non-wavelength conversion region of the first wavelength conversion element is located on a predetermined optical path of the first laser beam, the first laser module is in a closed state, and the second laser module is in an open state. The light guide assembly is disposed on the optical paths of the first wavelength conversion beam from the first wavelength conversion element and the second wavelength conversion beam from the second wavelength conversion element. The light guide assembly is used to filter the first wavelength conversion beam into a first color light and the second wavelength conversion beam into a second color light.

[0008] To achieve one or more of the above-mentioned objectives, or other objectives, one embodiment of the present invention provides a projection device, including the aforementioned illumination system, light valve, and projection lens. The light valve is disposed in the optical path of the illumination beam and is used to convert the illumination beam into an image beam, wherein the illumination beam includes at least one of a first color light, a second color light, and a first laser beam. The projection lens is disposed in the optical path of the image beam and is used to project the image beam outside the projection device.

[0009] Based on the above, the lighting system and projection device of the present invention have at least one of the following advantages: In the embodiments of the present invention, when the boundary between at least one first wavelength conversion region and at least one non-wavelength conversion region of the first wavelength conversion element is located on the predetermined optical path of the first laser beam, the first laser module is in a closed state, and the second laser module is in an open state. This avoids the first laser beam irradiating the boundary and generating unstable mixed-color light. Instead, the second laser beam provided by the second laser module forms a second color light through the second wavelength conversion element and the light guide assembly, allowing the light valve to open and receive the second color light. Therefore, by controlling the switching of the laser module, the switching frequency of the color beam received by the light valve per unit time is higher, and the lighting system and projection device of the present invention can achieve high brightness and good image quality. Furthermore, the combination of the laser module and the wavelength conversion element can effectively suppress laser speckle. Attached Figure Description

[0010] Figure 1A , Figure 1B , Figure 1C and Figure 1D These are schematic diagrams of the optical paths of a lighting system according to an embodiment of the present invention, when the first laser beam, the first color light, the second color light, and the third color light are transmitted to the light-monopolating element.

[0011] Figure 2 This is a schematic diagram of a projection device according to an embodiment of the present invention.

[0012] Figure 3 for Figure 2 A schematic diagram of the beam timing of the projection device.

[0013] Figure 4 for Figures 1A to 1D The spectra of the first and second laser beams, the spectrum of the third laser beam, the reflectance spectrum of the first dichroic mirror, and the reflectance spectrum of the second dichroic mirror are included.

[0014] Figure 5A , Figure 5B and Figure 5C for Figure 1A A front view schematic diagram of three variations of the first wavelength conversion element in the diagram.

[0015] Figure 6 To adopt Figure 5A A schematic diagram of the beam timing of the projection device of the first wavelength conversion element.

[0016] Figure 7A and Figure 7B for Figure 1A A front view schematic diagram of two other variations of the first wavelength conversion element and the second wavelength conversion element.

[0017] Figure 7C This is a schematic diagram of the optical path of a lighting system according to another embodiment of the present invention.

[0018] Figure 8A , Figure 8B , Figure 8C and Figure 8D The above are schematic diagrams of the optical paths of the lighting system according to another embodiment of the present invention when the first laser beam, the first color light, the second color light and the third color light are transmitted to the light homogenizing element.

[0019] Figure 9 To adopt Figures 8A to 8D A timing diagram of the projection device of the lighting system.

[0020] Figure 10 This is a schematic diagram of the optical path of a lighting system according to another embodiment of the present invention.

[0021] Figure 11 This is a schematic diagram of the optical path of a lighting system according to another embodiment of the present invention.

[0022] Figure 12 To adopt Figure 11 A schematic diagram of the beam timing of the projection device in the lighting system.

[0023] Explanation of reference numerals in the attached figures:

[0024] 50: Rotating substrate

[0025] 52: Central axis

[0026] 62: Laser Diode

[0027] 64: Reflector

[0028] 66: Photosynthetic element

[0029] 100, 100d, 100e, 100f: Lighting systems

[0030] 101: Illumination beam

[0031] 110: First laser module

[0032] 111: First laser beam

[0033] 120, 120a, 120b, 120c: First wavelength conversion element

[0034] 121: First wavelength conversion beam

[0035] 122: First wavelength conversion region

[0036] 123: Boundary

[0037] 124: Non-wavelength conversion region

[0038] 130: Second laser module

[0039] 131: Second laser beam

[0040] 140: Second wavelength conversion element

[0041] 141: Second wavelength conversion beam

[0042] 142: Second wavelength conversion region

[0043] 150: Light guide assembly

[0044] 152, 152', 152”: First dichroic mirror

[0045] 152a, 152a', 152a”: Part One

[0046] 152b, 152b', 152b”: Part Two

[0047] 154: Second Dichroic Mirror

[0048] 156: Third Dichroic Mirror

[0049] 160: Beam homogenizer

[0050] 170: Third laser module

[0051] 171, 173: Third laser beam

[0052] 172: First Sub-laser Module

[0053] 174: Second Sub-laser Module

[0054] 175: Fourth laser beam

[0055] 180: Diffuser element

[0056] 190: Fourth Dichroic Mirror

[0057] 200: Projection device

[0058] 210: Light valve

[0059] 211: Image Beam

[0060] 220: Projection lens

[0061] B, G, R, Y: Time period

[0062] C1: Primary color light

[0063] C2: Second color light

[0064] S1, S2: Light spots. Detailed Implementation

[0065] The foregoing descriptions and other technical contents, features, and effects of this invention will be clearly presented in the following detailed description of a preferred embodiment with reference to the accompanying drawings. The directional terms used in the following embodiments, such as up, down, left, right, front, or back, are merely for reference to the accompanying drawings. Therefore, the directional terms used are for illustrative purposes and not for limiting the invention.

[0066] Figure 1A , Figure 1B , Figure 1C and Figure 1D The diagram shows the optical path of a lighting system according to an embodiment of the present invention as the first laser beam, the first color light, the second color light, and the third color light are transmitted to the light-monopolating element. Please refer to... Figures 1A to 1DThe lighting system 100 of this embodiment includes a first laser module 110, a first wavelength conversion element 120, a second laser module 130, a second wavelength conversion element 140, and a light guide assembly 150. The first laser module 110 is used to emit a first laser beam 111 (shown in...). Figure 1A , Figure 1B and Figure 1D The first wavelength conversion element 120 includes at least one first wavelength conversion region 122 and at least one non-wavelength conversion region 124.

[0067] At least one first wavelength conversion region 122 and at least one non-wavelength conversion region 124 are sequentially located on the optical path of the first laser beam 111, and the first wavelength conversion element 120 is not located on the optical path of the second laser beam 131. At least one first wavelength conversion region 122 is used to convert the first laser beam 111 into a first wavelength-converted beam 121. The second laser module 130 is used to emit the second laser beam 131 (shown in...). Figure 1C The second wavelength conversion element 140 includes a second wavelength conversion region 142, which is located on the optical path of the second laser beam 131, while the second wavelength conversion element 140 is not located on the optical path of the first laser beam 111. The second wavelength conversion region 142 is used to convert the second laser beam 131 into a second wavelength converted beam 141. Figures 1A to 1D The two bottommost circular structures schematically illustrate frontal views of the first wavelength conversion element 120 and the second wavelength conversion element 140, respectively. The first wavelength conversion region 122 and the non-wavelength conversion region 124 of the first wavelength conversion element 120 are, for example, arranged in a ring, as are the second wavelength conversion region 142 of the second wavelength conversion element 140. The positions of the light spot S1 of the first laser beam 111 illuminating the first wavelength conversion element 120 and the light spot S2 of the second laser beam 131 emitted from the second laser module 130 illuminating the second wavelength conversion element 140 are also schematically shown.

[0068] The first wavelength conversion element 120 is, for example, a rotating wavelength conversion wheel, so that the first wavelength conversion region 122 and the non-wavelength conversion region 124 alternately enter the optical path of the first laser beam 111. In this embodiment, the second wavelength conversion element 140 is also, for example, a rotating wavelength conversion wheel, and the second laser beam 131 can irradiate the second wavelength conversion region 142. In this embodiment, as... Figure 1CAs shown, when the boundary 123 between at least one first wavelength conversion region 122 and at least one non-wavelength conversion region 124 of the first wavelength conversion element 120 is located on a predetermined optical path of the first laser beam 111, the first laser module 110 is in a closed state, and the second laser module 130 is in an open state. In one embodiment, when a portion of the first wavelength conversion region 122, the boundary 123, and a portion of the non-wavelength conversion region 124 are located on the predetermined optical path of the first laser beam 111, the first laser module 110 is in a closed state, and the second laser module 130 is in an open state. The aforementioned portion of the first wavelength conversion region 122 refers to the portion of the first wavelength conversion region 122 near the boundary 123, and the portion of the non-wavelength conversion region 124 refers to the portion of the non-wavelength conversion region 124 near the boundary 123.

[0069] A light guide assembly 150 is disposed on the optical paths of a first wavelength conversion beam 121 from a first wavelength conversion element 120 and a second wavelength conversion beam 141 from a second wavelength conversion element 140. The light guide assembly 150 is used to filter the first wavelength conversion beam 121 into a first color light C1 (the wavelength range of the first wavelength conversion beam 121 includes the wavelength range of the first color light C1), and to filter the second wavelength conversion beam 141 into a second color light C2 (the wavelength range of the second wavelength conversion beam 141 includes the wavelength range of the second color light C2). In this embodiment, the first laser beam 111 and the second laser beam 131 are, for example, blue laser beams, the first color light C1 is, for example, a green beam, and the second color light C2 is, for example, a red beam. The first wavelength conversion region 122 is, for example, a region coated with green or yellow phosphor, and the first wavelength conversion beam 121 is, for example, a yellow beam or a wider wavelength green beam, while the light guide assembly 150 filters the first wavelength conversion beam 121 into a purer (narrower wavelength) green beam. The second wavelength conversion region 142 is, for example, an area coated with yellow or red phosphor, and the second wavelength conversion beam 141 is, for example, a yellow beam or a wider band of red beam, while the light guide assembly 150 filters the second wavelength conversion beam 141 into a red beam or a narrower band of red beam.

[0070] In this embodiment, the light guide assembly 150 includes a first dichroic mirror 152 and a second dichroic mirror 154. The first dichroic mirror 152 is disposed between the first laser module 110 and the first wavelength conversion element 120, and is used to reflect a portion of the first wavelength conversion beam 121 to filter the first wavelength conversion beam 121 into a first color light C1. The second dichroic mirror 154 is disposed between the second laser module 130 and the second wavelength conversion element 140, and is used to reflect a portion of the second wavelength conversion beam 141 to filter the second wavelength conversion beam 141 into a second color light C2.

[0071] In this embodiment, the light guide assembly 150 further includes a third dichroic mirror 156, which is disposed between the first dichroic mirror 152 and the first laser module 110, and also between the first dichroic mirror 152 and the second dichroic mirror 154.

[0072] In one embodiment, the first wavelength conversion element 120 may be, for example, a reflective phosphor wheel, and the non-wavelength conversion region 124 of the first wavelength conversion element 120 is used to reflect the first laser beam 111 to the first dichroic mirror 152. Alternatively, in another embodiment, the first wavelength conversion element 120 may be, for example, a transmissive phosphor wheel, and the non-wavelength conversion region 124 is used to allow the first laser beam 111 to pass through, and it can be transmitted to the first dichroic mirror 152 along an optical path by means of a light guiding element (such as a reflector).

[0073] In this embodiment, a portion of the first laser beam 111 is reflected by the first dichroic mirror 152, and another portion of the first laser beam 111 penetrates the first dichroic mirror 152 and is then reflected by the third dichroic mirror 156. The first dichroic mirror 152 can be divided into a first part 152a and a second part 152b. The second part 152b is used to allow the first laser beam 111 from the first laser module 110 to pass through and to reflect the first wavelength conversion beam 121. The first part 152a is used to reflect the first wavelength conversion beam 121, to allow a portion (e.g., half) of the first laser beam 111 from the non-wavelength conversion region 124 to pass through, and to reflect another portion (e.g., the other half) of the first laser beam 111 from the non-wavelength conversion region 124. The first dichroic mirror 152 is used to allow the second color light C2 from the second dichroic mirror 154 to pass through.

[0074] In this embodiment, the illumination system 100 further includes a light-diffusing element 160, which is disposed on the light path of the first color light C1 reflected by the first dichroic mirror 152, on the light path of the second color light C2 reflected by the second dichroic mirror 154 and then passing through the first dichroic mirror 152, and on the light path of the first laser beam 111 reflected by the first dichroic mirror 152 and the third dichroic mirror 156. The light-diffusing element 160 is, for example, a light integrating column or a lens array, used to homogenize the light beam.

[0075] In one embodiment, the lighting system 100 further includes a third laser module 170 for providing a third laser beam 171, and a light guide component 150 is disposed on the light path of the third laser beam 171. The color of the third laser beam 171 corresponds to the color of the first color light C1 or the color of the second color light C2, thereby effectively increasing the light intensity of the first color light C1 or the second color light C2. Figures 1A to 1DIn this embodiment, the third laser beam 171 is a red laser. The third laser beam 171 emitted by the third laser module 170 passes through the second dichroic mirror 154, the third dichroic mirror 156 and the first dichroic mirror 152 in sequence and is transmitted to the light-diffusing element 160.

[0076] Figure 2 This is a schematic diagram of a projection device according to an embodiment of the present invention. Figure 3 for Figure 2 A schematic diagram of the beam timing of the projection device. Please refer to... Figures 1A to 1D , Figure 2 and Figure 3 The projection device 200 of this embodiment includes the aforementioned illumination system 100, light valve 210, and projection lens 220. The light valve 210 is disposed in the optical path of the illumination beam 101 and is used to convert the illumination beam 101 into an image beam 211. The illumination beam 101 includes at least one of a first color light C1, a second color light C2, and a first laser beam 111. That is, the first color light C1, the second color light C2, and the first laser beam 111 enter the homogenizing element 160 at multiple time intervals, are homogenized by the homogenizing element 160, and exit from the homogenizing element 160 to form the illumination beam 101 directed towards the light valve 210. The projection lens 220 is disposed in the optical path of the image beam 211 and is used to project the image beam 211 outside the projection device 200, for example, onto a screen or various types of imaging surfaces, to form a projected image. In this embodiment, the first color light C1 and the second color light C2 filtered by the first dichroic mirror 152 and the second dichroic mirror 154 have high color purity, which can improve the color purity of the green or red dots in the projected image.

[0077] In this embodiment, the light valve 210 is, for example, a digital micromirror device (DMD), a liquid-crystal-on-silicon panel (LCOS panel), or other suitable spatial light modulator, which can modulate the illumination beam 101 into an image beam 211. The projection lens 220 includes, for example, a combination of one or more optical lenses with refractive power, such as various combinations of non-planar lenses including biconcave lenses, biconvex lenses, concave-convex lenses, convex-concave lenses, plano-convex lenses, and plano-concave lenses. In one embodiment, the projection lens 220 may also include an optical reflective lens to reflectively project the image beam 211 from the light valve 210 onto the projection target. The embodiments of the present invention do not limit the type or form of the projection lens 220.

[0078] In this embodiment, as Figure 1DAs illustrated, when a portion of the first wavelength conversion region 122 is located on the optical path of the first laser beam 111 emitted by the first laser module 110, both the first laser module 110 and the second laser module 130 are in the on state, causing the first color light C1 and the second color light C2 from the light guide component 150 to be superimposed to form a third color light. In this embodiment, the third color light is, for example, a yellow beam.

[0079] In this embodiment, within a time period (e.g., during the time it takes for the first wavelength conversion element 120 to rotate 360 ​​degrees), the first color light C1, the third color light, the second color light C2, the first laser beam 111, and the second color light C2 from the light guide assembly 150 are sequentially transmitted to the light homogenizing element 160, which can be referred to as Figure 3 The timing diagram is shown below. In this embodiment, the first color light C1 is a green beam, represented by "G" in the timing diagram; the third color light is a yellow beam, represented by "Y" in the timing diagram; the second color light C2 is a red beam, represented by "R" in the timing diagram; and the first laser beam 111 is a blue beam, represented by "B" in the timing diagram.

[0080] Figure 3 The time sequence of the G period in the text corresponds to... Figure 1B In this state, the first laser module 110 is turned on, the first laser beam 111 irradiates the first wavelength conversion region 122, and the second laser module 130 is turned off.

[0081] Figure 3 The time sequence of the Y period in the text corresponds to... Figure 1D In this state, both the first laser module 110 and the second laser module 130 are turned on, and the first laser beam 111 and the second laser beam 131 irradiate the first wavelength conversion region 122 and the second wavelength conversion region 142, respectively. In one embodiment, the third laser module 170 may be turned on in the sequence corresponding to the Y time period.

[0082] Figure 3 The time sequence of the R period in the text corresponds to... Figure 1AAt this time, as the first wavelength conversion element 120 rotates, the boundary 123 between the first wavelength conversion region 122 and the non-wavelength conversion region 124 enters the predetermined optical path of the first laser beam 111. For example, when the R-period corresponds to a portion of the first wavelength conversion region 122, the boundary 123, and a portion of the non-wavelength conversion region 124 located on the predetermined optical path of the first laser beam 111, in order to prevent unstable mixed-color light from entering the light valve 210, this embodiment uses the method of turning off the first laser module 110 to avoid this problem. At this time, the second laser module 130 remains on, allowing the second color light C2 to be incident on the light valve 210. Therefore, the light valve 210 does not need to be closed at this time, and can continue to convert the illumination beam 101 into the image beam 211 without causing a loss of brightness. Therefore, the illumination system 100 and projection device 200 of this embodiment can achieve high brightness. In one embodiment, the third laser beam 171 can also be turned on in the sequence corresponding to the R-period, that is, the third laser beam 171 can be turned on in at least one of the R-period and the Y-period. In embodiments employing a third laser beam 171 as a light source, the period during which the third laser beam 171 is activated at least partially overlaps with the activation period of the second laser module 130. Figure 3 For example, the period when the third laser beam 171 is turned on completely overlaps with the period when the second laser module 130 is turned on.

[0083] Figure 3 The B time period in the text corresponds to Figure 1C At this time, the first laser module 110 is turned on, and the first laser beam 111 irradiates the non-wavelength conversion region 124.

[0084] In this embodiment, the first laser module 110 and the first wavelength conversion element 120 correspond to one of the R-time period and the G-time period. Figure 3 Taking time period G as an example, the first laser module 110 is turned on during time period G and time period B; by assigning the second laser module 130 and the second wavelength conversion element 140 to one of time periods R and G (Figure 7 takes time period R as an example), the second laser module 130 corresponding to time period R (or time period G) is turned on at the boundary time between time period G and time period B (or the boundary time between time period R and time period B).

[0085] Figure 4 for Figures 1A to 1DThe spectra of the first laser beam 111 and the second laser beam 131, the spectrum of the third laser beam 171, the reflectance spectrum of the first portion 152a of the first dichroic mirror 152, the reflectance spectrum of the first dichroic mirror 152 (first portion 152a and second portion 152b), and the reflectance spectrum of the second dichroic mirror 154 are included. In this embodiment, the transmittance of the third laser beam 171 to the light guide assembly 150 is greater than or equal to 90%. The spectral overlap area of ​​the first color light C1 and the second color light C2 is less than 15% of the spectral area of ​​either the first color light C1 or the second color light C2. Figure 4 In this embodiment, the spectra of the first laser beam 111 and the second laser beam 131 are taken as the same; however, in other embodiments, their spectra may be different. In this embodiment, the second portion 152b of the first dichroic mirror 152 is used to reflect beams with wavelengths from 491 nm to 582 nm (such as the first color light C1) and allow light of other wavelengths to pass through; the first portion 152a of the first dichroic mirror 152 is used to reflect beams with wavelengths from 491 nm to 582 nm (such as the first color light C1), allowing a portion (e.g., 50%) of beams with wavelengths from 435 nm to 485 nm (such as the first laser beam 111) to pass through, and reflecting another portion (e.g., another 50%) of beams with wavelengths from 435 nm to 485 nm, and allowing light of other wavelengths to pass through; the second dichroic mirror 154 is used to reflect beams with wavelengths from 583 nm to 636 nm (such as the second color light C2). The dominant wavelength of the third laser beam 171 is at least 636 nanometers, which is greater than or equal to the maximum wavelength of the beam that can be reflected by the second dichroic mirror 152.

[0086] In this embodiment, the lighting system 100 further includes a diffuser element 180, disposed on the optical path of the third laser beam 171 and located between the third laser module 170 and the light guide assembly 150. In this embodiment, the third laser beam 171 is, for example, a laser, and the diffuser element 180 can suppress the speckle phenomenon generated by the third laser beam 171. In this embodiment, the diffuser element 180 is, for example, a fixed element (such as a diffuser sheet) or a moving element (such as a diffuser wheel), both of which have the effect of suppressing speckle. In other embodiments, the lighting system 100 may not employ the third laser module 170 and the diffuser element 180.

[0087] In this embodiment, the excitation spectrum of the first wavelength conversion region 122 of the first wavelength conversion element 120 is different from the excitation spectrum of the second wavelength conversion region 142 of the second wavelength conversion element 140. The spectral overlap area of ​​the first wavelength conversion beam 121 and the second wavelength conversion beam 141 may, for example, be less than or equal to 15% of the spectral area of ​​either the first wavelength conversion beam 121 or the second wavelength conversion beam 141. For example, in this embodiment, the first wavelength conversion region 122 has green phosphor, while the second wavelength conversion region 142 has yellow phosphor. In other embodiments, the excitation spectrum of the first wavelength conversion region 122 of the first wavelength conversion element 120 is the same as the excitation spectrum of the second wavelength conversion region 142 of the second wavelength conversion element 140; for example, both the first wavelength conversion region 122 and the second wavelength conversion region 142 have yellow phosphor. In this embodiment, the second wavelength conversion element 120 is a moving element, such as a rotatable phosphor wheel. In other embodiments, the second wavelength conversion element 120 may also be a fixed element, such as a fluorescent element. The rotational speeds of the first wavelength conversion element 120 and the second wavelength conversion element 140 may be the same or different. In the lighting system 100 of this embodiment, the laser speckle phenomenon can be effectively suppressed by generating the first wavelength conversion beam 121 and the second wavelength conversion beam 141 by the first wavelength conversion element 120 and the second wavelength conversion element 140.

[0088] In this embodiment, the first laser module 110, the second laser module 130, and the third laser module 170 may each include multiple laser diodes 62, multiple reflectors 64, and multiple light combining elements 66. The light combining elements 66 and the reflectors 64 can combine the light emitted by the multiple laser diodes 62 into a single laser beam, such as a first laser beam 111, a second laser beam 131, or a third laser beam 171. In this way, the optical path volume can be reduced by translating or bending the optical paths of the first laser module 110, the second laser module 130, and the third laser module 170.

[0089] Figure 5A , Figure 5B and Figure 5C for Figure 1A A front view schematic diagram of three variations of the first wavelength conversion element. Please refer to... Figure 5A , Figure 5B and Figure 5C In these three embodiments, the first wavelength conversion elements 120a, 120b, and 120c each have a plurality of first wavelength conversion regions 122 and a plurality of non-wavelength conversion regions 124 arranged alternately, and there is a boundary 123 between adjacent first wavelength conversion regions 122 and non-wavelength conversion regions 124. Taking the first wavelength conversion element 120a as an example, its applicable timing diagram is as follows. Figure 6 The drawing shows that it is similar to Figure 3Compared to the timing diagram, the G, Y, R, B, R time periods are divided twice as many times within the range of a 360-degree rotation of the first wavelength conversion element 120a. In another embodiment, the Y time period can be omitted, and the time periods are sequentially G, Y, R, B, R, G, R, B, R. Figures 5A to 5C In this embodiment, when the rotational speed of the first wavelength conversion elements 120a, 120b, and 120c remains unchanged, the lighting system can achieve a higher color refresh rate by dividing the 360-degree rotation range into more than double the number of G, Y, R, B, and R time periods, effectively avoiding the problem of color distortion. Furthermore, since this operating principle does not require increasing the rotational speed of the first wavelength conversion elements 120a, 120b, and 120c, the problem of excessive motor noise can be effectively avoided.

[0090] Figure 7A and Figure 7B for Figure 1A A front view schematic diagram of two other variations of the first wavelength conversion element and the second wavelength conversion element. Please refer to... Figure 7A The first wavelength conversion element 120 and the second wavelength conversion element 140 are located on the same rotating substrate 50, and the distance from the first wavelength conversion element 120 to a central axis 52 of the rotating substrate 50 is not equal to the distance from the second wavelength conversion element 140 to the central axis 52 of the rotating substrate 50. Figure 7A In this case, the distance from the first wavelength conversion element 120 to the central axis 52 of the rotating substrate 50 is less than the distance from the second wavelength conversion element 140 to the central axis 52 of the rotating substrate 50. Figure 7B In this configuration, the distance from the first wavelength conversion element 120c to the central axis 52 of the rotating substrate 50 is greater than or equal to the distance from the second wavelength conversion element 140 to the central axis 52 of the rotating substrate 50. The first wavelength conversion element 120 and the second wavelength conversion element 140 can form concentric circles. Figure 7B The first wavelength conversion element 120c, the second wavelength conversion element 140, and the rotating substrate 50 can be applied to, for example... Figure 7C In lighting systems, and Figure 7C In the rotating substrate 50, the light spot S1 irradiating the first wavelength conversion element 120c and the light spot S2 irradiating the second wavelength conversion element 140 are located on opposite sides of the rotating substrate 50. On the reference plane of the rotating substrate 50, the central axis 52 is located between the light spot S1 and the light spot S2.

[0091] Figure 8A , Figure 8B , Figure 8C and Figure 8D These are schematic diagrams of the optical paths of a lighting system according to another embodiment of the present invention, showing the transmission of a first laser beam, a first color light, a second color light, and a third color light to a uniform light element. Figure 9 To adopt Figures 8A to 8D The timing diagram of the projection device in the lighting system. Please refer to... Figures 8A to 8D and Figure 9 The lighting system 100d in this embodiment is similar to Figures 1A to 1D The lighting system 100d of this embodiment has two main differences, as described below. In the lighting system 100d of this embodiment, the first wavelength conversion region 122 has yellow phosphor, the second wavelength conversion region 142 has green phosphor, the first dichroic mirror 152' filters the first wavelength conversion beam 121 into a red beam, that is, the first color light C1 is a red beam, and the second dichroic mirror 154 filters the second wavelength conversion beam 141 into a green beam, that is, the second color light C2 is a green beam. Specifically, the second part 152b' of the first dichroic mirror 152' can reflect red light while allowing light of other wavelengths to pass through, and the first part 152a' of the first dichroic mirror 152' can reflect red light, allow a portion (e.g., 50%) of blue light to pass through, and reflect another portion (e.g., another 50%) of blue light, while allowing light of other wavelengths to pass through. The timing diagram of the projection device is as follows. Figure 9 As illustrated, the incident light periods on the light valve 210 are sequentially R, Y, G, B, and G segments within a time period. The first laser module 110 is activated during the R and B segments; the second laser module 130 and the second wavelength conversion element 140 correspond to the G segment, and the second laser module 130 corresponding to the G segment is activated at the boundary between the R and B segments. The color of the third laser beam 171 can correspond to the color of the first color light C1, and the activation period of the third laser beam 171 at least partially overlaps with the activation period of the first laser module 110. Figure 9 Taking the period when the third laser beam 171 is turned on partially overlapping with the period when the first laser module 110 is turned on as an example, in Figure 9 The third laser beam 171 is only activated during the R and Y periods.

[0092] Figure 10 This is a schematic diagram of the optical path of a lighting system according to another embodiment of the present invention. Please refer to... Figure 10 The lighting system 100e in this embodiment and Figure 1ASimilar to the lighting system 100, the main difference lies in that, in the lighting system 100e of this embodiment, the third laser beam 171 emitted by the third laser module 170 is a green beam, and the period during which the third laser beam 171 is turned on at least partially overlaps with the period during which the first laser module 110 is turned on. Furthermore, the third laser beam 171 can penetrate the first dichroic mirror 152”. Compared to the first color light C1 reflected by the first dichroic mirror 152”, which is a green light with a relatively broad spectrum, the third laser beam 171 is a green light with a relatively narrow spectrum. The first dichroic mirror 152” has a lower reflectivity within the narrower wavelength range corresponding to the spectrum of the third laser beam 171, allowing the third laser beam 171 to penetrate the first dichroic mirror 152”. The green light wavelength range outside this narrower wavelength range has a high reflectivity to reflect the first color light C1. Specifically, the dominant wavelength of the third laser beam 171 (i.e., green light) emitted by the third laser module 170 is, for example, 525 nanometers. The coating spectral design of the first dichroic mirror 152”, the second dichroic mirror 154, and the third dichroic mirror 156 ensures that the transmission efficiency of the third laser beam 171 (i.e., green light) from the third laser module 170 is greater than or equal to 90%. In this embodiment, the spectral transmission and reflection range of the second part 152b” of the first dichroic mirror 152” is designed to reflect light in the 491 nm to 520 nm and 530 nm to 582 nm wavelength bands, while allowing light in the remaining wavelength bands to pass through. The reflection spectrum of the first part 152a” of the first dichroic mirror 152” for green light is the same as that of the second part 152b”, but it reflects a portion (e.g., 50%) of the blue light and allows another portion (e.g., the remaining 50%) of the blue light to pass through. In this embodiment, the third laser beam 171 is activated during both the G and Y time periods, or only during the G time period.

[0093] Figure 11 This is a schematic diagram of the optical path of a lighting system according to another embodiment of the present invention. Figure 12 To adopt Figure 11 A beam timing diagram of the projection device in the lighting system. Please refer to... Figure 11 and Figure 12The lighting system 100f of this embodiment is similar to the lighting system 100 of FIG. 1, with the main differences as described below. In the lighting system 100f of this embodiment, the third laser module 170f is used to provide a third laser beam 173 and a fourth laser beam 175. For example, the third laser module 170f includes a first sub-laser module 172 and a second sub-laser module 174, used to provide the third laser beam 173 and the fourth laser beam 175, respectively. The color of the third laser beam 173 corresponds to the color of the first color light C1, and the color of the fourth laser beam 175 corresponds to the color of the second color light C2. In this embodiment, the third laser beam 173 is, for example, a green beam, and the fourth laser beam 175 is, for example, a red beam. In this embodiment, the transmittance of the third laser beam 173 to the light guide component 150 is greater than or equal to 90%, and the transmittance of the fourth laser beam 175 to the light guide component 150 is greater than or equal to 90%. In this embodiment, the period during which the fourth laser beam 175 is activated at least partially overlaps with the activation period of the second laser module 130, and the period during which the third laser beam 173 is activated at least partially overlaps with the activation period of the first laser module 110. In this embodiment, the illumination system 100f may include a fourth dichroic mirror 190, which merges the optical paths of the fourth laser beam 175 and the third laser beam 173. For example, the fourth dichroic mirror 190 is used to reflect green light and to allow red light to pass through, thus merging the optical paths of red and green light. In this embodiment, the fourth laser beam 175 is activated corresponding to both the R and Y periods, or only during the R period.

[0094] The diffusion element 180 can be configured on the optical path of the third laser beam 173 and the fourth laser beam 175, and is located between the third laser module 170f and the light guide assembly 150. The diffusion element can be a fixed element or a moving element.

[0095] In summary, the lighting system and projection device of the embodiments of the present invention have at least one of the following advantages: In the embodiments of the present invention, when the boundary between at least one first wavelength conversion region and at least one non-wavelength conversion region of the first wavelength conversion element is located on the predetermined optical path of the first laser beam, the first laser module is in a closed state, and the second laser module is in an open state. This avoids the first laser beam irradiating the boundary and generating unstable mixed-color light. Instead, the second laser beam provided by the second laser module forms a second color light through the second wavelength conversion element and the light guide assembly, allowing the light valve to open and receive the second color light. Therefore, by controlling the switching of the laser module, the switching frequency of the color beam received by the light valve per unit time is higher, and the lighting system and projection device of the embodiments of the present invention can achieve high brightness and good image quality. Furthermore, the combination of the laser module and the wavelength conversion element can effectively suppress laser speckle.

[0096] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the invention. Any simple equivalent changes and modifications made in accordance with the claims and description of the invention are still within the scope of this patent. Furthermore, no embodiment or claim of the present invention needs to achieve all the objectives, advantages, or features disclosed in the invention. In addition, the abstract and title are only used to assist in patent document retrieval and are not intended to limit the scope of the invention. Moreover, the terms "first," "second," etc., mentioned in this specification or claims are only used to name elements or distinguish different embodiments or scopes, and are not used to limit the upper or lower limit of the number of elements.

Claims

1. A lighting system, characterized in that, The lighting system includes a first laser module, a first wavelength conversion element, a second laser module, and a second wavelength conversion element, wherein: The first laser module is used to emit a first laser beam; The first wavelength conversion element includes at least one first wavelength conversion region and at least one non-wavelength conversion region, wherein the at least one first wavelength conversion region and the at least one non-wavelength conversion region are located sequentially on the optical path of the first laser beam, and the at least one first wavelength conversion region is used to convert the first laser beam into a first wavelength conversion beam. The second laser module is used to emit a second laser beam; The second wavelength conversion element includes a second wavelength conversion region located on the optical path of the second laser beam. The second wavelength conversion region is used to convert the second laser beam into a second wavelength converted beam. The first laser module is in a closed state and the second laser module is in an open state when the boundary between the at least one first wavelength conversion region and the at least one non-wavelength conversion region of the first wavelength conversion element is located on a predetermined optical path of the first laser beam. The light guide component is disposed on the optical paths of the first wavelength conversion beam from the first wavelength conversion element and the second wavelength conversion beam from the second wavelength conversion element. The light guide component is used to filter the first wavelength conversion beam into a first color light and to filter the second wavelength conversion beam into a second color light.

2. The lighting system according to claim 1, characterized in that, When a portion of the first wavelength conversion region is located on the optical path of the first laser beam emitted by the first laser module, both the first laser module and the second laser module are in the on state, so that the first color light from the light guide component and the second color light are superimposed to form the third color light.

3. The lighting system according to claim 2, characterized in that, The lighting system further includes a light-diffusing element, wherein within a time period, the first color light, the third color light, the second color light, the first laser beam, and the second color light from the light guide assembly are sequentially transmitted to the light-diffusing element.

4. The lighting system according to claim 1, characterized in that, The light guide assembly includes a first dichroic mirror and a second dichroic mirror, wherein: The first dichroic mirror is disposed between the first laser module and the first wavelength conversion element, and is used to reflect a portion of the first wavelength conversion beam to filter the first wavelength conversion beam into the first color light, and to transmit the first color light to the homogenizing element; and The second dichroic mirror is disposed between the second laser module and the second wavelength conversion element, and is used to reflect part of the second wavelength conversion beam to filter the second wavelength conversion beam into the second color light, and to transmit the second color light to the homogenizing element.

5. The lighting system according to claim 4, characterized in that, The light guide assembly further includes a third dichroic mirror, which is disposed between the first dichroic mirror and the first laser module. The non-wavelength conversion region of the first wavelength conversion element is used to reflect the first laser beam to the first dichroic mirror. A portion of the first laser beam is reflected by the first dichroic mirror, and another portion of the first laser beam penetrates the first dichroic mirror and is then reflected by the third dichroic mirror.

6. The lighting system according to claim 1, characterized in that, The lighting system further includes a third laser module for providing at least one of a third laser beam and a fourth laser beam, and the light guide component is disposed on the light path of the third laser beam and the fourth laser beam, wherein the color of the third laser beam corresponds to the color of the first color light, and the color of the fourth laser beam corresponds to the color of the second color light.

7. The lighting system according to claim 6, characterized in that, The third laser beam has a transmittance of 90% or more to the light guide component, and the fourth laser beam has a transmittance of 90% or more to the light guide component.

8. The lighting system according to claim 6, characterized in that, The period during which the fourth laser beam is activated at least partially overlaps with the period during which the second laser module is activated.

9. The lighting system according to claim 6, characterized in that, The period during which the third laser beam is activated at least partially overlaps with the period during which the first laser module is activated.

10. The lighting system according to claim 6, characterized in that, The lighting system further includes a diffusion element disposed on the optical path of at least one of the third laser beam and the fourth laser beam, and located between the third laser module and the light guide assembly.

11. The lighting system according to claim 10, characterized in that, The diffusion element can be a stationary element or a moving element.

12. The lighting system according to claim 1, characterized in that, The spectral overlap area between the first color light and the second color light is less than 15% of the spectral area of ​​either the first color light or the second color light.

13. The lighting system according to claim 1, characterized in that, The lighting system further includes a third laser module for providing a third laser beam, and the light guide assembly is disposed on the light path of the third laser beam, wherein the color of the third laser beam corresponds to the color of the first color light or the color of the second color light.

14. The lighting system according to claim 1, characterized in that, The excitation spectrum of the first wavelength conversion region of the first wavelength conversion element is the same as the excitation spectrum of the second wavelength conversion region of the second wavelength conversion element.

15. The lighting system according to claim 1, characterized in that, The excitation spectrum of the first wavelength conversion region of the first wavelength conversion element is different from the excitation spectrum of the second wavelength conversion region of the second wavelength conversion element.

16. The lighting system according to claim 1, characterized in that, The second wavelength conversion element is a fixed element or a moving element.

17. The lighting system according to claim 1, characterized in that, The first wavelength conversion element and the second wavelength conversion element may rotate at the same or different speeds.

18. The lighting system according to claim 1, characterized in that, The first wavelength conversion element and the second wavelength conversion element are located on the same rotating substrate, and the distance from the first wavelength conversion element to the central axis of the rotating substrate is not equal to the distance from the second wavelength conversion element to the central axis of the rotating substrate.

19. A projection device, characterized in that, The projection device includes an illumination system, a light valve, and a projection lens, wherein: The lighting system includes a first laser module, a first wavelength conversion element, a second laser module, and a second wavelength conversion element, wherein: The first laser module is used to emit a first laser beam; The first wavelength conversion element includes at least one first wavelength conversion region and at least one non-wavelength conversion region, wherein the at least one first wavelength conversion region and the at least one non-wavelength conversion region are located sequentially on the optical path of the first laser beam, and the at least one first wavelength conversion region is used to convert the first laser beam into a first wavelength conversion beam. The second laser module is used to emit a second laser beam; The second wavelength conversion element includes a second wavelength conversion region located on the optical path of the second laser beam. The second wavelength conversion region is used to convert the second laser beam into a second wavelength-converted beam. The first laser module is in a closed state and the second laser module is in an open state when the boundary between the at least one first wavelength conversion region and the at least one non-wavelength conversion region of the first wavelength conversion element is located on a predetermined optical path of the first laser beam. The light guide component is disposed on the optical paths of the first wavelength conversion beam from the first wavelength conversion element and the second wavelength conversion beam from the second wavelength conversion element. The light guide component is used to filter the first wavelength conversion beam into a first color light and to filter the second wavelength conversion beam into a second color light. The light valve is disposed on the optical path of the illumination beam and is used to convert the illumination beam into an image beam, wherein the illumination beam includes at least one of the first color light, the second color light, and the first laser beam; and The projection lens is positioned on the optical path of the image beam and is used to project the image beam outside the projection device.

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