Projection system

Abstract

The application provides a projection system. The projection system comprises: a first laser emitting a first excitation light, a second laser emitting a second excitation light, the wavelength bands of the first excitation light and the second excitation light are different and coherent; a light combining device is located on the light emitting side of the laser; the first excitation light and the second excitation light are incident on a static fluorescent device through the light combining device; the projection system comprises multiple frames of projection images; a first primary color time sequence is that only the first laser emits the first excitation light, the first excitation light is incident on the static fluorescent device to output the first primary color; a second primary color time sequence is that only the second laser emits the second excitation light, the second excitation light is incident on the static fluorescent device to output the second primary color; and a third primary color time sequence is that the first laser and the second laser emit light at the same time, the first excitation light and the second excitation light are incident on the static fluorescent device at the same time to output the third primary color. The application solves the problems of large volume and limited display color gamut of the projection system in the prior art.

Description

Technical Field

[0001] This invention relates to the field of optical technology, and more specifically, to a projection system. Background Technology

[0002] In current laser projection architectures, the projection system typically uses a monochromatic blue laser combined with a phosphor wheel to generate a three-color light source. The timing of the light is controlled by the angle of the phosphor wheel's sector, which introduces structural errors and makes white balance adjustment difficult. The sector angle tolerance of the phosphor wheel itself leads to errors in the proportions of the RGB colors, resulting in deviations in the white field's color points and increasing the difficulty of ensuring consistency. The usual approach is to adjust the current to correct the white field color points, but compared to three-color LEDs or three-color lasers, the final consistency of the adjusted white field color points is relatively poor.

[0003] Meanwhile, the projection system incorporates a phosphor wheel. Due to the phosphor wheel's large outer diameter, the overall size of the optical engine increases, leading to a larger overall projector size. In practical applications, after the phosphor wheel is excited by a monochromatic laser, a color wheel is also used for color filtering, further increasing the size. Furthermore, using a single laser for excitation limits the final color gamut, thus limiting the richness of colors that can be represented.

[0004] In other words, existing projection systems suffer from large size and limited color gamut. Summary of the Invention

[0005] The main objective of this invention is to provide a projection system that solves the problems of large size and limited color gamut in existing projection systems.

[0006] To achieve the above objectives, the present invention provides a projection system comprising: a laser, including a first laser and a second laser, wherein the first laser emits a first excitation light and the second laser emits a second excitation light, the wavelengths of the first excitation light and the second excitation light do not overlap, and the first excitation light and the second excitation light interfere with each other; a beam combiner located on the light-emitting side of the laser; and a static phosphor device, wherein the first excitation light and the second excitation light are incident on the static phosphor device after passing through the beam combiner; the projection system includes multiple projected images, each projected image including a first primary color timing sequence, a second primary color timing sequence, and a third primary color timing sequence; the first primary color timing sequence is that only the first laser emits the first excitation light, and the first excitation light is incident on the static phosphor device to output the first primary color; the second primary color timing sequence is that only the second laser emits the second excitation light, and the second excitation light is incident on the static phosphor device to output the second primary color; and the third primary color timing sequence is that both the first laser and the second laser emit light, and the first excitation light and the second excitation light are simultaneously incident on the static phosphor device to output the third primary color.

[0007] Furthermore, there is a phase difference between the first excitation light and the second excitation light.

[0008] Furthermore, the wavelength of one of the first and second excitation lights is at least twice the wavelength of the other.

[0009] Furthermore, the optical axis of the first laser and the optical axis of the second laser intersect on the beam combining device, and the beam combining device is used to reflect one of the first excitation light and the second excitation light, and to transmit the other of the first excitation light and the second excitation light.

[0010] Furthermore, the first excitation light is violet light, the second excitation light is blue light, the first primary color is green light, the second primary color is blue light, and the third primary color is red light.

[0011] Furthermore, the difference between the spectral bandwidth of the first excitation light and the spectral bandwidth of the second excitation light is greater than or equal to 70 nm.

[0012] Furthermore, the spectral bandwidth of the first excitation light is greater than or equal to 200 nm and less than or equal to 350 nm; and / or the spectral bandwidth of the second excitation light is greater than or equal to 400 nm and less than or equal to 500 nm.

[0013] Furthermore, the projection system also includes a beam splitter. The first excitation light is violet light, and the second excitation light is blue light. The beam splitter is used to split the blue light into two beams, one of which is used to excite the phosphor of the static phosphor device to form a fourth primary color.

[0014] Furthermore, the static phosphor device has a variety of phosphors, and different types of phosphors are used to absorb excitation light of different wavelengths. The multiple phosphors include at least a first phosphor and a second phosphor, and the spectral bandwidth range of the first phosphor is different from that of the second phosphor.

[0015] Furthermore, the first phosphor is a red phosphor, the material of which includes Y2O3:Eu; and / or the second phosphor is a green phosphor, the material of which includes β-thionol and LuAG:Ce.

[0016] According to the technical solution of this invention, the projection system includes a laser, a beam combiner, and a static phosphor device. The laser includes a first laser and a second laser. The first laser emits a first excitation light, and the second laser emits a second excitation light. The wavelengths of the first and second excitation lights do not overlap, and they interfere with each other. The beam combiner is located on the light-emitting side of the laser. The first and second excitation lights are incident on the static phosphor device after passing through the beam combiner. The projection system includes multiple frames of projected images. Each frame of projected image includes a first primary color timing sequence, a second primary color timing sequence, and a third primary color timing sequence. The first primary color timing sequence is that only the first laser emits the first excitation light, and the first excitation light is incident on the static phosphor device to output the first primary color. The second primary color timing sequence is that only the second laser emits the second excitation light, and the second excitation light is incident on the static phosphor device to output the second primary color. The third primary color timing sequence is that both the first and second lasers emit light, and the first and second excitation lights are simultaneously incident on the static phosphor device to output the third primary color.

[0017] This application employs a first laser and a second laser to emit excitation light in different wavelengths. The wavelengths of the first and second excitation lights are designed to be non-overlapping, and they interfere with each other. This allows the first and second excitation lights to create a multiphoton excitation effect on various phosphors in the static phosphor device. Especially when the two interfering excitation lights act simultaneously, a higher energy level can be achieved, resulting in a wider color gamut and richer displayed colors. Simultaneous excitation with two lasers allows for control of the RGB three-color timing sequence in the subsequent optical path system, ensuring a more accurate and consistent white point in the final mixed light. Furthermore, this application uses a static phosphor device instead of a rotating phosphor wheel, avoiding the size increase associated with a dynamic phosphor wheel and contributing to the miniaturization of the projection system. By rationally setting the on / off times of the first, second, and third primary color timing sequences, control of the RGB three-color timing sequence in the subsequent optical path system can be achieved, resulting in a more accurate and consistent white point in the final mixed light. Attached Figure Description

[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0019] Figure 1 A schematic diagram of the optical path of a projection system according to an optional embodiment of the present invention is shown;

[0020] Figure 2 A schematic diagram of the energy level transitions of a projection system according to an alternative embodiment of the present invention is shown;

[0021] Figure 3A schematic diagram of coherent light wave superposition in the prior art is shown;

[0022] Figure 4 A schematic diagram of an optional superposition of two coherent light waves according to the present invention is shown;

[0023] Figure 5 A schematic diagram of another optional superposition of two coherent light waves according to the present invention is shown;

[0024] Figure 6 The spectral bandwidth diagrams of two excitation lights in an alternative embodiment of the present invention are shown;

[0025] Figure 7 A color gamut diagram of a projection system in the prior art is shown;

[0026] Figure 8 A color gamut diagram of a projection system according to an alternative embodiment of the present invention is shown;

[0027] Figure 9 The spectrum of a static fluorescent device excited by violet light according to an optional embodiment of the present invention is shown.

[0028] Figure 10 The spectrum of a blue light-excited static fluorescent device according to an optional embodiment of the present invention is shown.

[0029] Figure 11 The diagram shows the spectrum of a static fluorescent device simultaneously excited by blue and violet light according to an alternative embodiment of the present invention.

[0030] The above figures include the following reference numerals:

[0031] 10. First laser; 20. Second laser; 30. Combiner; 40. Static phosphor. Detailed Implementation

[0032] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0033] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0034] In this invention, unless otherwise stated, directional terms such as "upper," "lower," "top," and "bottom" are generally used in relation to the direction shown in the accompanying drawings, or in relation to the vertical, perpendicular, or gravitational direction of the component itself; similarly, for ease of understanding and description, "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0035] To address the problems of large size and limited color gamut in existing projection systems, this invention provides a projection system.

[0036] like Figures 1 to 11 As shown, the projection system includes a laser, a beam combiner 30, and a static phosphor device 40. The laser includes a first laser 10 and a second laser 20. The first laser 10 emits a first excitation light, and the second laser 20 emits a second excitation light. The wavelengths of the first excitation light and the second excitation light do not overlap, and they interfere with each other. The beam combiner 30 is located on the light-emitting side of the laser. The first excitation light and the second excitation light are incident on the static phosphor device 40 after passing through the beam combiner 30. The projection system includes multiple projected images, each of which includes a first primary color timing sequence, a second primary color timing sequence, and a third primary color timing sequence. In the first primary color timing sequence, only the first laser 10 emits a first excitation light, which is incident on the static fluorescent device 40 to output the first primary color. In the second primary color timing sequence, only the second laser 20 emits a second excitation light, which is incident on the static fluorescent device 40 to output the second primary color. In the third primary color timing sequence, both the first laser 10 and the second laser 20 emit light, and the first and second excitation lights are simultaneously incident on the static fluorescent device 40 to output the third primary color.

[0037] This application employs a first laser 10 and a second laser 20 to emit excitation light in different wavelengths. The wavelengths of the first and second excitation lights are designed to be non-overlapping, and they interfere with each other. This allows the first and second excitation lights to create a multiphoton excitation effect on various phosphors in the static phosphor device 40. Especially when the two interfering excitation lights act simultaneously, a higher energy level can be achieved, resulting in a wider color gamut and richer displayed colors. Simultaneous excitation with two lasers enables control over the RGB three-color timing sequence in the subsequent optical path system, ensuring a more accurate and consistent white point in the final mixed light. Furthermore, this application uses a static phosphor device 40 instead of a rotating phosphor wheel, avoiding the size increase associated with a dynamic phosphor wheel and facilitating the miniaturization of the projection system. By controlling the on / off times of the projection system in the aforementioned three primary color timing sequences, control over the RGB three-color timing sequence in the subsequent optical path system can be achieved. Adjusting and recording the timing sequence for each machine ensures a more accurate and consistent white point in the final mixed light.

[0038] It should be noted that the aforementioned static fluorescent device 40 is a static, non-rotating fluorescent device.

[0039] Specifically, the interference between the first and second excitation beams is achieved by adjusting the phase of the emitted light from the two lasers, creating a phase difference between the two beams, thus enabling constructive interference. This results in higher energy and a wider color gamut when the two beams are superimposed.

[0040] When the interference between the first and second excitation beams is adjusted, a multiphoton excitation effect can be achieved on the phosphor in the static fluorescent device 40. Under the combined action of the two coherent beams, the phosphor can reach a higher energy level. For example... Figure 2 As shown, in typical single-photon excitation, the absorption of a photon causes an electron in the material to transition from one energy level to another, producing light emission or other electronic excitation effects. In multiphoton excitation, multiple photons are required, with a sufficiently high total energy, to excite an electron to transition to a higher energy level, thereby generating light when it transitions back to the ground state. This is the theoretical basis of the light-emitting system provided in this patent, and this phenomenon can serve as the foundation for achieving the effect of forming multiple light sources through fluorescence excitation of several light sources.

[0041] Furthermore, due to the coherence properties of light waves, any two light waves of the same wavelength and phase can superimpose, depending on the interference patterns of different light waves. Ordinary interference theory uses two light waves of the same frequency for demonstration. (Refer to...) Figure 3 1 and 2 represent two light waves of the same frequency, while 0 represents the effect of the two light waves being superimposed. Based on different understandings of interference, the interference of light waves mentioned above can be described as the superposition of light waves. Since any two light waves can be superimposed, in the description of multiphoton interference, it is not necessary to achieve a state of interference at the same frequency. Instead, a superposition state is achieved after two light waves of different wavelengths control their phases to form a phase difference. After superposition, the energy of the two light waves will be higher at a certain time, thus exciting the phosphor photons. (Reference) Figure 4 When green and blue light are superimposed, the red light can be seen as a superimposed state of light waves. During some periods after superposition, the energy exceeds that of the original green light waves, thus allowing for differentiation.

[0042] Of course, there are many combinations of wavelength and phase settings to achieve superimposed peaks with higher energy, for example... Figure 5As shown in the diagram, after setting two wavelengths to interfere, the superimposed waveform shown in the image below will be produced. The peak energy of the superimposed waveform will exceed the amplitude of the original wavelength, thus possessing higher energy for fluorescence excitation. Therefore, the combination of wavelength and phase can be selected according to requirements. Furthermore, the concept of coherence needs further understanding. It is explained as follows: the coherence of two light waves means that there is a certain relatively stable phase relationship between them, causing them to interfere at certain positions and times. This coherence indicates that the wave characteristics of light waves are coordinated in space and time, enabling them to produce ordered interference patterns.

[0043] Specifically, the wavelength of one of the first excitation light and the second excitation light is at least twice the wavelength of the other. Since the spectral bandwidth used to excite the phosphor needs to be a wide range, it is necessary to set a difference space between the spectral bandwidth ranges of the two excitation lights involved in the phase interference, so that the spectral bandwidth ranges of the two excitation lights involved in the phase interference cannot be too close.

[0044] In specific embodiments of this application, the light source combinations that can be formed include: a first laser 10 emitting a first excitation light, a second laser 20 emitting a second excitation light, the first laser 10 emitting the first excitation light to excite the phosphor, the second laser 20 emitting the second excitation light to excite the phosphor, and the first laser 10 and the second laser 20 emitting light simultaneously to excite the phosphor, thereby enabling this application to use two lasers to achieve five light source combinations.

[0045] According to the basic principle of fluorescence excitation, longer-wavelength light must be excited by shorter-wavelength light of higher energy. Therefore, the light that excites the phosphor will have a longer wavelength than the light emitted by the laser. Thus, in practical applications, the first laser 10 and the second laser 20 are typically selected in the blue or ultraviolet light bands to excite longer-wavelength visible light such as red and green light. Preferably, the first laser 10 emits ultraviolet light, and the second laser 20 emits blue light.

[0046] Specifically, the difference between the spectral bandwidth of the first excitation light and the spectral bandwidth of the second excitation light is greater than or equal to 70 nm. Since the spectral bandwidth of the lasers used to excite phosphors is currently a relatively wide range, it is necessary to set a difference range between the spectral bandwidths of the two excitation lights.

[0047] In this embodiment, the first excitation light is violet light, and the spectral bandwidth of the first excitation light is greater than or equal to 200 nm and less than or equal to 350 nm, preferably greater than or equal to 300 nm and less than or equal to 350 nm; the second excitation light is blue light, and the spectral bandwidth of the second excitation light is greater than or equal to 400 nm and less than or equal to 500 nm. By reasonably selecting the spectral bandwidths of the two excitation lights, the spectra of the two excitation lights are not too close, which helps to ensure that the spectral bandwidth of the laser excitation of the phosphor is a relatively wide range.

[0048] Specifically, the optical axis of the first laser 10 and the optical axis of the second laser 20 intersect on the beam combining device 30, and the beam combining device 30 is used to reflect one of the first excitation light and the second excitation light, and transmit the other of the first excitation light and the second excitation light. In a specific embodiment of this application, the beam combining device 30 is a beam combining lens. The first laser 10 emits violet light, the second laser 20 emits blue light, the line connecting the first laser 10 to the beam combining lens is perpendicular to the line connecting the beam combining lens to the static fluorescence device 40, the second laser 20 is located on the side of the beam combining lens away from the static fluorescence device 40, and the line connecting the second laser 20 to the beam combining lens is on the same straight line as the line connecting the static fluorescence device 40 to the beam combining lens. The beam combining lens is used to reflect violet light and transmit blue light.

[0049] In a preferred embodiment of this application, a wavelength of 225 nm ultraviolet light is selected as the emission spectrum of the first laser 10, and a wavelength of 450 nm blue light is selected as the emission spectrum of the second laser 20. That is, the first excitation light is 225 nm ultraviolet light, and the second excitation light is 450 nm blue light. The spectral value of the second excitation light is twice that of the first excitation light. This simple multiple relationship of wavelengths is more conducive to the wave coherence of light. In practical applications, the phase of the light from the first laser 10 and the second laser 20 is adjusted so that the first and second excitation lights undergo constructive interference when they reach the static phosphor device 40, forming an energy superposition to excite the phosphor. The blue light can directly enter the projection system of the subsequent optical path and be used for color mixing as blue visible light. The phosphor in the 225 nm ultraviolet static phosphor device 40 forms green light, which then enters the projection system of the subsequent optical path and is used for color mixing as green visible light. 450nm blue light and 225nm violet light together excite the phosphor to produce red light, which enters the projection system in the subsequent optical path and is mixed as red visible light.

[0050] Specifically, the first primary color timing is as follows: only the first laser 10 emits the first excitation light, which excites the phosphor on the static phosphor device 40 to output the first primary color; the second primary color timing is as follows: only the second laser 20 emits the second excitation light, which passes through the static phosphor device 40 to output the second primary color; the third primary color timing is as follows: both the first laser 10 and the second laser 20 emit light, and the first and second excitation lights simultaneously excite the phosphor on the static phosphor device 40 to output the third primary color. When the first excitation light is violet light with a wavelength of 225nm and the second excitation light is blue light with a wavelength of 450nm, the first primary color is green, the second primary color is blue, and the third primary color is red.

[0051] Therefore, by controlling the on / off times of the projection system in the aforementioned three primary color sequences, the RGB three-color sequences in the subsequent optical path system can be controlled. Adjusting and recording the sequence for each machine allows for more accurate and consistent white color points in the final mixed light. Furthermore, since the linear phosphor wheel angle partitioning is not required, the static phosphor device 40 of this application can be functionally achieved using only a static phosphor sheet, provided heat dissipation is adequate, further reducing the size of the projection system.

[0052] Based on the above embodiments, a light combining system forming four color light sources can be further optimized. The light source portion still uses 450nm blue light and 225nm ultraviolet light, as in the previous embodiment, and still illuminates the static phosphor device 40. The difference lies in adding a beam splitter with a certain transmittance to split the 450nm blue light into two beams: one beam is used directly, and the other is used to excite the phosphor in the static phosphor device 40. For example, the arrangement and excitation sequence are as follows: the 225nm ultraviolet light excites the 500nm cyan light alone; the 450nm blue light portion provides direct illumination; the 450nm blue light portion excites the red light; and the 225nm ultraviolet light and 450nm blue light together excite the green light. This forms an effective light source with four wavelengths: blue, cyan, green, and red, achieving a wider color gamut.

[0053] In the concept of color gamut, current projection and display methods on color coordinate diagrams mostly use three-color displays, for reference... Figure 7 On a color coordinate system, there are three reference monochromatic color coordinates. Colors within a defined range can be created by mixing the colors of three light sources at different intensities; this range is called the color gamut. The color gamut determines the richness of colors a projector or monitor can display. In the color mixing scenarios using the four effective light sources mentioned above, adding a cyan light source further expands the color gamut, resulting in richer displayed colors. (See reference...) Figure 8 .

[0054] In summary, in the above embodiments, two lasers are actually used. Of course, in the optional embodiments of this application, the number of lasers can be increased to achieve more types of light source colors.

[0055] Specifically, the static fluorescent device 40 has a variety of phosphors, and the different phosphors are used to absorb the excitation light of different wavelengths. The multiple phosphors include at least a first phosphor and a second phosphor, and the spectral bandwidth range of the first phosphor is different from that of the second phosphor.

[0056] In a specific embodiment of this application, the static phosphor device 40 includes a first phosphor, a second phosphor, and a binder. The first phosphor is a red phosphor, and the material of the red phosphor includes Y2O3:Eu; the red phosphor accounts for 1%-20% of the total content; Reference Figure 9 Irradiating a red phosphor with 250nm violet light can produce 615nm red light. The second phosphor is a green phosphor, whose materials include β-thionyl ether and LuAG:Ce. The green phosphor accounts for 20%–50% of the total composition. (Reference) Figure 10 When 450nm blue light illuminates a green phosphor, it can produce 540nm green light. (Reference) Figure 11 Simultaneous illumination of red and green phosphors with 250nm violet light and 450nm blue light can produce yellow or white light. The binder can be organic or inorganic, and accounts for 30%-60% of the total composition.

[0057] Obviously, the embodiments described above are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0058] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0059] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0060] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A projection system, characterized in that, include: The laser includes a first laser (10) and a second laser (20), wherein the first laser (10) emits a first excitation light and the second laser (20) emits a second excitation light, wherein the wavelengths of the first excitation light and the second excitation light do not overlap and the first excitation light and the second excitation light interfere with each other; A light combining device (30) is located on the light-emitting side of the laser; The static fluorescent device (40) is formed by the first excitation light and the second excitation light passing through the light combining device (30) and then incident on the static fluorescent device (40). The projection system includes multiple frames of projected images, and each frame of the projected image includes a first primary color timing sequence, a second primary color timing sequence, and a third primary color timing sequence. The first primary color timing is that only the first laser (10) emits the first excitation light, and the first excitation light is incident on the static fluorescent device (40) to output the first primary color; The second primary color timing is that only the second laser (20) emits the second excitation light, and the second excitation light is incident on the static fluorescent device (40) to output the second primary color; The third primary color timing is such that both the first laser (10) and the second laser (20) emit light, and the first excitation light and the second excitation light are simultaneously incident on the static fluorescent device (40) to output the third primary color.

2. The projection system according to claim 1, characterized in that, There is a phase difference between the first excitation light and the second excitation light.

3. The projection system according to claim 1, characterized in that, The wavelength of one of the first excitation light and the second excitation light is at least twice the wavelength of the other.

4. The projection system according to claim 1, characterized in that, The optical axis of the first laser (10) intersects the optical axis of the second laser (20) on the beam combining device (30), and the beam combining device (30) is used to reflect one of the first excitation light and the second excitation light, and to transmit the other of the first excitation light and the second excitation light.

5. The projection system according to claim 1, characterized in that, The first excitation light is violet light, and the second excitation light is blue light. The first primary color is green light; The second primary color is blue light; The third primary color is red light.

6. The projection system according to claim 1, characterized in that, The difference between the spectral bandwidth of the first excitation light and the spectral bandwidth of the second excitation light is greater than or equal to 70 nm.

7. The projection system according to claim 1, characterized in that, The spectral bandwidth of the first excitation light is greater than or equal to 200 nm and less than or equal to 350 nm; and / or the spectral bandwidth of the second excitation light is greater than or equal to 400 nm and less than or equal to 500 nm.

8. The projection system according to claim 5, characterized in that, The projection system further includes a beam splitter, wherein the first excitation light is violet light and the second excitation light is blue light. The beam splitter is used to split the blue light into two beams, one of which is used to excite the phosphor of the static fluorescent device (40) to form a fourth primary color.

9. The projection system according to claim 1, characterized in that, The static fluorescent device (40) has a variety of phosphors, and different types of phosphors are used to absorb excitation light of different wavelengths. The various phosphors include at least a first phosphor and a second phosphor, and the spectral bandwidth range of the first phosphor is different from that of the second phosphor.

10. The projection system according to claim 9, characterized in that, The first phosphor is a red phosphor, and the material of the red phosphor includes Y2O3:Eu; and / or The second phosphor is a green phosphor, and the material of the green phosphor includes one of β-thionol and LuAG:Ce.

Images