CN111142324A

CN111142324A - Fixed wavelength conversion device and projector using same

Info

Publication number: CN111142324A
Application number: CN201811308794.2A
Authority: CN
Inventors: 蔡锦盛; 云麒锥
Original assignee: Young Optics Inc
Current assignee: Young Optics Inc
Priority date: 2018-11-05
Filing date: 2018-11-05
Publication date: 2020-05-12

Abstract

A fixed wavelength conversion device comprises a substrate, a fluorescent material layer and a heat dissipation element, wherein the substrate is provided with a first reflecting surface, the fluorescent material layer is arranged on the first reflecting surface of the substrate, the heat dissipation element is connected to the substrate, and the substrate is fixed and can not rotate. The invention further provides a projector, which includes a first light source, a light splitting element and the fixed wavelength conversion device, wherein a first reflection surface of the fixed wavelength conversion device is disposed downstream of the first light source and the light splitting element. The invention further provides a projector, which includes a first light source, a substrate, a fluorescent material layer, a light splitting element, a base and a scattering element, wherein the fluorescent material layer is disposed on the substrate, the light splitting element is disposed between the first light source and an optical path of the fluorescent material layer, the fluorescent material layer is fixed in the base through the substrate, and the heat dissipation element is thermally connected to another surface of the substrate opposite to the fluorescent material layer.

Description

Fixed wavelength conversion device and projector using same

Technical Field

The present invention relates to a wavelength conversion device and a projector using the same, and more particularly, to a non-rotatable fixed wavelength conversion device applicable to a projector and a projector using the same.

Background

A color wheel or a fluorescent wheel is usually included in the conventional projection apparatus. The color wheel may be disposed on a transmission path of an illumination beam (illumination beam) transmitted by the projection apparatus. The color wheel is provided with a plurality of filter parts (filter parts) which are composed of a red filter part with uniform dichroism, a green filter part with uniform dichroism and a blue filter part with uniform dichroism. Such a color wheel design usually requires a motor to drive the color wheel to rotate, so that when the color wheel rotates to make the red filter portion, the green filter portion and the blue filter portion sequentially align with the illumination beam, the illumination beam is sequentially filtered into red light, green light and blue light, so that the projection apparatus can project a color display image. Moreover, the light receiving area of the color wheel or the fluorescent wheel is annular through the rotation of the color wheel or the fluorescent wheel, so that the light receiving area is effectively increased, and the problem that the surface of an element is damaged due to heat accumulation can be avoided.

However, the rotation of the color wheel or the fluorescent wheel inevitably causes vibration and noise problems, and the projection quality of the projection apparatus is limited by the service life of the driving motor and cannot be further extended.

Disclosure of Invention

Compared with the prior color wheel or fluorescent wheel, the embodiment of the invention provides a fixed wavelength conversion device which can be arranged statically during application and does not need to be driven by a motor, thereby avoiding the problems of vibration and noise generated by the conventional rotating mode, and further prolonging the service life of elements because the motor is not needed. In this embodiment, the fixed wavelength conversion device at least includes a substrate, a phosphor layer and a heat dissipation element, wherein the phosphor layer is disposed on the reflective surface of the substrate and can be excited by the short wavelength light to output a long wavelength light. The heat dissipation element is connected to the other side of the substrate opposite to the reflecting surface, and the substrate is fixed and can not rotate, so that the heat energy of the fluorescent material layer can be taken away, and the problem that the surface of the element is damaged due to heat accumulation caused by the fact that the fixing element can not rotate is avoided.

In another embodiment of the present invention, a projector is provided, which includes a fixed wavelength conversion device, wherein the fixed wavelength conversion device can be installed in a stationary manner without driving a motor, thereby avoiding the problems of vibration and noise caused by the conventional rotation method, and further prolonging the life of the components without the need of a motor. In this example, the projector includes a light source, a light splitting element, and a fixed wavelength conversion device. The fixed wavelength conversion device comprises a substrate, a fluorescent material layer and a heat dissipation element. The fluorescent material layer is arranged on the reflecting surface of the substrate. The reflecting surface is arranged on the downstream of the light source and the light path of the light splitting element. The heat dissipation element is connected to the substrate. Although the substrate is fixed and can not rotate, the heat dissipation element can carry away the heat energy of the fluorescent material layer, thereby avoiding the problem that the surface of the element is damaged due to the accumulation of heat of the fixing element.

Similarly, another embodiment of the invention provides another projector. The projector comprises a light source, a substrate, a fluorescent material layer, a light splitting element, a base and a heat dissipation element. The fluorescent material layer is arranged on the substrate. The fluorescent material layer is fixed in the base through the substrate. The heat dissipation element is connected to the other surface of the substrate opposite to the fluorescent material layer. Therefore, the heat dissipation performance of the projector can be enhanced through the heat dissipation element. Therefore, the problems of vibration and noise generated by the conventional rotation mode can be avoided, and the service life of the element can be further prolonged because a motor is not needed.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood, the present invention may be implemented in accordance with the content of the description, and in order to make the above and other objects, features, and advantages of the present invention more clearly understood, the following preferred embodiments are described in detail with reference to the accompanying drawings.

Drawings

Fig. 1 is a schematic view of a projector according to an embodiment of the invention.

Fig. 2 is a schematic view of a projector according to another embodiment of the invention.

FIG. 3A is a schematic diagram of one embodiment of the stationary wavelength conversion device of FIG. 1.

FIG. 3B is a schematic diagram of another embodiment of the stationary wavelength conversion device of FIG. 1.

FIG. 4 is a schematic diagram of a fixed wavelength conversion device according to another embodiment of the invention.

FIG. 5 is a schematic diagram of a fixed wavelength conversion device according to another embodiment of the invention.

Detailed Description

The projector of the embodiment of the invention provides a fixed wavelength conversion device which can avoid the problems of vibration, noise, limited service life and the like caused by a rotating mode. Moreover, the heat dissipation element can avoid the problem that the fluorescent material layer is overheated and burnt out due to the fact that the fluorescent powder layer cannot rotate and energy is excessively concentrated in a specific range. The following are further described in specific examples.

Referring to fig. 1-3B, fig. 1 is a schematic diagram of a projector 1 according to an embodiment of the invention, fig. 2 is a schematic diagram of a projector 2 according to another embodiment of the invention, fig. 3A is a schematic diagram of one implementation of the fixed wavelength conversion device 110 of fig. 1, and fig. 3B is a schematic diagram of another implementation of the fixed wavelength conversion device 110 of fig. 1. The projector 1 is divided into four parts according to the functions, including a light source, a light combination module, a light valve and a projection lens, wherein the light source provides illumination beams, and the light combination module combines the illumination beams and outputs the combined illumination beams to the light valve; the light valve can convert the illumination beam into an image beam, and the image beam is adjusted by the projection lens and output to an image plane, such as a screen.

As can be seen from the figure, in the embodiment, the projector 1 includes a fixed wavelength conversion device 110, a base 115, a light source 120, a light source 130, a light source 140, a light splitting element 150, a light splitting element 160, a prism 170, a light valve 180, and a projection lens 190. The fixed wavelength conversion device 110, the light source 120, the light source 130, and the light source 140 may be regarded as a part of a light source module, and the light splitting element 150, the light splitting element 160, the prism 170, and elements (not shown) therebetween may be regarded as a part of a light combining module. The following describes each element in an embodiment of the present invention.

As shown in fig. 3A and 3B, the fixed wavelength conversion device 110 can convert a shorter wavelength light beam incident thereto into a longer wavelength light beam. For example, incident light, such as UV light or blue light, may be converted into a green light beam or a red light beam. Referring to fig. 3A, in the present embodiment, the fixed wavelength conversion device 110 includes a substrate 111, a phosphor layer 112, a heat dissipation element 113, and an optical element group 114.

In the example of fig. 3A, the substrate 111 has a cylindrical outer contour and is in the shape of a bowl or cup with a central portion recessed. A reflection surface 111A (for example, referred to as a first reflection surface), a reflection surface 111B (for example, referred to as a second reflection surface) provided around the reflection surface 111A, and a reflection surface 111C (for example, referred to as a third reflection surface) provided around the reflection surface 111B are provided at an inner center portion of the substrate 111. The

reflective surfaces

111A, 111B, and 111C reflect the light beams. In the present embodiment, the reflection surface 111A is a circular plane, the reflection surface 111B is a curved solid surface, and the reflection surface 111C is annular. The three reflecting

surfaces

111A, 111B, and 111C are continuous surfaces, and the reflecting surface 111C is connected to the reflecting surface 111A via the reflecting surface 111B. In other words, in the present embodiment, the substrate 111 has an integral (ONE PIECE FORMED) structure. In the present embodiment, each of the

reflective surfaces

111A, 111B, and 111C of the substrate 111 may be formed by polishing, for example, by a machining process, or may be formed on the surface of the substrate 111 by a process such as coating, plating, and the like. The substrate 111 may be made of metal, ceramic (e.g., AlN or ZrO), plastic, or other polymer materials. If necessary, the inner surface of the substrate 111 may be a non-smooth surface with poor light reflectivity or a black light absorbing material coated on any or all of the

reflecting surfaces

111A, 111B, and 111C.

In contrast to the design of the substrate 111 in the previous embodiment, the design of the substrate set 111' is modified in another embodiment of the present invention, as shown in fig. 3B. In the present embodiment, the first substrate 1111 and the second substrate 1112 are similar to the substrate 111 of the previous embodiment in overall appearance, but the substrate group 111' is formed by combining a plurality of elements. In this embodiment, the first substrate 1111 and the second substrate 1112 can be assembled after being manufactured separately. As shown in fig. 3B, the first substrate 1111 is a reflective cup, and a recess 1111a is formed at an end portion thereof, in this embodiment, the recess 1111a of the first substrate 1111 is a through hole, but the first substrate 1111 may be a recessed blind hole if necessary. And the second substrate 1112 is disposed in the recess 1111 a. Because the substrates are manufactured separately, an interface is provided between the first substrate 1111 and the second substrate 1112 after assembly. After assembly, the first substrate 1111 and the second substrate 1112 may directly contact or maintain a gap therebetween. Furthermore, if necessary, the reflection portion may also be a separate element, such as a reflection ring, which has a third reflection surface 111C inside and is connected to the other end of the first substrate 1111, for a corresponding effect.

The fluorescent material layer 112, which is one of wavelength conversion material layers, converts the light beam into a light beam of a different wavelength. In the present embodiment, the phosphor layer 112 includes a phosphor and can convert a blue light beam into a green light beam, or convert a blue light beam into a red light beam. In addition, in the present embodiment, the Phosphor layer 112 includes ceramic Phosphor (Phosphor), but the Phosphor layer 112 may also be made of glass-mixed Phosphor (Phosphor in phosphors) or mixed Phosphor (Phosphor in glue) in whole or in part.

The heat dissipation member 113 may conduct heat and convect the heat to the outside. The heat dissipation element 113 is made of a material with good thermal conductivity, such as a metal, specifically copper or aluminum, for example, other elements that can be used for heat energy transmission or exchange, such as heat dissipation fins, thermoelectric cooler (TEC), heat pipes, heat spreader (VC), or a combination thereof.

The optical element set 114 can selectively diffuse or condense the light beam passing through and the total diopter can be equal to, greater than or less than zero. The optical element set 114 can be various optical lenses, prisms, beam splitters, polarizers, or light blocking/shielding elements capable of reflecting, absorbing part of the light or allowing at least part of the light to pass through. In this example, the optical element set 114 includes a biconcave lens with a negative single diopter.

Referring to fig. 3B, it can be seen that the phosphor layer 112 is disposed on the reflective surface 111A of the substrate 111, and can convert the incident light beam L11 (e.g. blue light) into a light beam L14 (e.g. green light) with different wavelengths, and the un-excited blue light is reflected by the reflective surface 111A to excite the phosphor in the phosphor layer 112 again. In another embodiment, the fluorescent material layer 112 may also extend to cover the reflective surface 111B or extend to cover the

reflective surfaces

111B and 111C to increase the possible conversion area of the light beam L14, further reducing the concentration of light and improving the heat dissipation performance.

The heat dissipation element 113 is thermally connected to the substrate 111 or the substrate 1112, for example, the heat dissipation element 113 is thermally connected to the other surface of the substrate 111 opposite to the fluorescent material layer 112. The heat dissipation element 113 can dissipate the heat conducted from the light beam L11 to the substrate 111 out of the fixed wavelength conversion device 110 through heat conduction, radiation, and heat convection. Although the substrate 111 is fixed and non-rotatable, the power of the light beam can be dispersed by increasing the surface quality of the phosphor layer 112, and the heat dissipation element 113 is used to conduct the heat of the substrate 111 to the outside, so as to prevent the phosphor layer 112 from being burned by the light beam L11. Since the substrate 111 is fixed, the conventional motor and the motor driving design can be omitted. Furthermore, when any part of the optical element set 114 is connected to the substrate 111, the two parts can be selectively sealed to form a sealed space, and the sealed space can have the function of preventing dust from entering, as illustrated in fig. 3A-5, which is an example, other materials or mechanisms such as glue, rings, etc. can be added between the optical element set 114 and the substrate 111 to extend the distance between the two parts and maintain the sealed state. Furthermore, there is no limit to the space between the optical element set 114 and the substrate 111, and the space between the two may be separately arranged.

The phosphor layer 112 and the heat sink 113 may be assembled with the first substrate 1111 after being disposed on the second substrate 1112, so as to improve the manufacturability and/or assembly of the fixed wavelength conversion device 110.

The optical element group 114 is disposed on the other side of the fluorescent material layer 112 opposite to the substrate 111, and the optical element group 114 is connected to the substrate 111. The optical element set 114 can expand the light beam L11 from the light source 120 to expand the illumination area incident on the phosphor layer 112, so as to reduce the power density per unit area and further avoid burning the phosphor layer 112. In this way, even if the substrate 111 is fixed and non-rotatable, the small-area spot irradiation is converted into the large-area surface irradiation by the optical element group 114, so as to prevent the fluorescent material layer 112 from being burned. Note that the stronger the light intensity of the fluorescent material layer 112, the higher the light conversion efficiency of the fluorescent material layer 112, but the more difficult the heat dissipation of the fluorescent material layer 112 is. Therefore, the design is preferably applied to a high-power light source system, which is more efficient.

The

light sources

120, 130, and 140 are, for example, packaged led modules, laser light sources, or other types of light sources. The

light sources

120, 130 and 140 of the embodiment of the invention are laser light sources. The

light sources

120, 130, and 140 may emit fixed single color light beams, such as a first color light beam L11, a second color light beam L12, and a third color light beam L13. The first color light beam L11, the second color light beam L12, and the third color light beam L13 are, for example, blue light beams, red light beams, and blue light beams, respectively, but the embodiment of the invention is not limited thereto. In addition, the power of the

light sources

120, 130 and 140 is between 20-200 watts, which has the basic effect; the benefit is better when the power is between 30 and 120 watts, and the benefit is better when the power is between 50 and 100 watts. The total power consumption of each light source in the projector 1 is more than 100, 200 and 500 watts and less than 1000 watts, respectively, which has good, better and better benefits. In this example, the power of each light source is about 95 watts, and the total power consumption of each light source of the projector 1 is 300 to 500 watts.

The

beam splitters

150 and 160 are optical elements provided with a light combining function, such as prisms, Dichroic mirrors (Dichroic mirrors), and Polarizing Beam Splitters (PBS). In this example, the

light splitting elements

150 and 160 are, for example, dichroic mirrors that allow light beams provided with a first wavelength to pass and reflect light beams provided with a second wavelength, wherein the first wavelength is different from the second wavelength. In the present embodiment, the light splitting element 150 allows green light to pass through but reflects blue light and red light, and the light splitting element 160 allows green light and red light to pass through but reflects blue light. However, the embodiments of the present invention are not limited thereto.

The PRISM 170 may be a total reflection PRISM (TIR PRISM) group or a total reflection inverse PRISM (RTIR PRISM) group. In the embodiment, in order to create the total reflection surface, an air gap is optionally disposed between the prisms. In other embodiments, the prism 170 may be replaced by an optical element such as a field lens or a mirror that directs light to the light valve 180.

The light valve 180 is a word with a wide application, and in the embodiment, the light valve 180 can convert the illumination light into an image light with a fixed pattern. Any one of a digital micro lens array (DMD), a Liquid Crystal Display (LCD) and a Liquid Crystal On Silicon (LCOS) panel can be used as the light valve according to the embodiment of the present invention, and in this case, the light valve 180 is a DMD.

The projection lens 190 may include a plurality of optical elements such as a lens, a prism, a diaphragm, etc., and the projection lens 190 may adjust the profile of the image light or correct the aberration of the image light, etc. and output the adjusted image light.

As shown in fig. 1, the fixed wavelength conversion device 110, the

light sources

120, 130, and 140, the

beam splitters

150 and 160, the prism 170, the light valve 180, and the projection lens 190 are disposed in the base 115. As shown in fig. 1, 3A and 3B, the light splitting element 150 is disposed between the light source 120 and the light path of the fluorescent material layer 112. The substrate 111 is disposed in the mount 115 such that the fluorescent material layer 112 disposed on the substrate 110 can be fixed in the mount 115 through the substrate 111.

The fixed wavelength conversion device 110 is disposed downstream of the light source 120 and the light splitting element 150 in the optical path. The light source 120 emits a light beam L11. The light beam L11 is reflected by the light splitting element 150 to the fixed wavelength conversion device 110. The fixed wavelength conversion device 110 may convert the light beam L11 into a light beam L14 of a different wavelength and reflect the light beam L14. The light beam L14 passes through the beam splitter 150, the beam splitter 160, the prism 170 and the light valve 180 in sequence. The light source 130 emits a light beam L12. The light beam L12 passes through the beam splitter 150, the beam splitter 160, the prism 170 and the light valve 180 in sequence. The light source 140 emits a light beam L13. The light beam L13 passes through the beam splitter 160, the prism 170 and the light valve 180 in sequence.

As shown in fig. 2, the projector 2 includes a fixed wavelength conversion device 110, a base 215, a light source 220 (e.g., a first light source), a light source 230, a light source 240, a light splitting element 250, a light splitting element 260, a prism 270, a light valve 280, and a projection lens 290. The base 215, the light source 220, the light source 230, the light source 240, the light splitting element 260, the prism 270, the light valve 280 and the projection lens 290 are similar to the base 115, the light source 120, the light source 130, the light source 140, the light splitting element 160, the prism 170, the light valve 180 and the projection lens 190, respectively, and therefore, the description thereof is omitted.

The fixed wavelength conversion device 110 is disposed downstream of the light source 220 and the light splitting element 250 in the optical path. The light source 220 emits a light beam L21. The light beam L11 passes through the light splitting element 250 to the fixed wavelength conversion device 110. The fixed wavelength conversion device 110 may convert the light beam L21 into a light beam L24 of a different wavelength and reflect the light beam L24. The light beam L24 is guided through the beam splitter 250, the beam splitter 260, the prism 270 and the light valve 280. The light source 230 emits a light beam L22. The light beam L22 is guided through the beam splitter 250, the beam splitter 260, the prism 270 and the light valve 280. The light source 240 emits a light beam L23. The light beam L23 is guided through the beam splitter 260, the prism 270 and the light valve 280.

Referring to fig. 4, a schematic diagram of a fixed wavelength conversion device 210 according to another embodiment of the invention is shown. The fixed wavelength conversion device 210 includes a substrate 211, a phosphor layer 212, a heat dissipation element 213, and an optical element group 214. The fixed wavelength conversion devices 110 of the

projectors

1 and 2 may be replaced with fixed wavelength conversion devices 210.

The heat dissipation element 213 and the optical element group 214 are similar to the heat dissipation element 113 and the optical element group 114, respectively.

The substrate 211 has a reflective surface 211A (e.g., a first reflective surface), a second reflective surface 211B (e.g., a second reflective surface), and a reflective surface 211C (e.g., a third reflective surface), wherein the reflective surface 211C is connected to the reflective surface 211A via the reflective surface 211B. In the present embodiment, the

reflective surfaces

211A and 211B are continuous surfaces, such as continuous curved surfaces, and the reflective surface 211C is annular. In addition, the reflective surface 211A and the reflective surface 211B can be connected smoothly, i.e., the tangential directions of the connection portions substantially overlap, but can also be connected in a turning manner.

As shown in fig. 4, the phosphor layer 212 is formed in conformity with the reflective surface 211A, and thus the phosphor layer 212 is also curved. In another embodiment, the phosphor layer 212 may also extend to cover the reflective surface 211B, or to cover the

reflective surfaces

211B and 211C.

Referring to fig. 5, a schematic diagram of a fixed wavelength conversion device 310 according to another embodiment of the invention is shown. The fixed wavelength conversion device 310 includes a substrate 311, a phosphor layer 312, a heat sink 313 and an optical element group 314. The fixed wavelength conversion devices 110 of the

projectors

1 and 2 may be replaced with fixed wavelength conversion devices 310.

The heat dissipation element 313 and the optical element group 314 are similar to the heat dissipation element 113 and the optical element group 114, respectively.

The substrate 311 has a reflective surface 311A (e.g., a first reflective surface), a second reflective surface 311B (e.g., a second reflective surface), and a reflective surface 311C (e.g., a third reflective surface), wherein the reflective surface 211C is connected to the reflective surface 311A via the reflective surface 211B. In this embodiment, the reflective surface 311A and the reflective surface 311B are continuous surfaces, and the reflective surface 311C has an annular shape. The reflecting surface 311A and the reflecting surface 311B are connected to be a continuous surface. In this embodiment, the substrate 311 further includes a substrate portion 3111 and a ring portion 3112, wherein the substrate 311 is provided with the reflective surface 311A and the reflective surface 311B, and the ring portion 3112 is provided with the reflective surface 311C. The annular portion 3112 is connected to the substrate portion 3111. The ring portion 3112 and the substrate portion 3111 may be manufactured separately and then joined by bonding, screwing, engaging, or the like. The annular portion 3112 and the substrate portion 3111 are separate, but in another embodiment, the annular portion 3112 and the substrate portion 3111 may be integrally formed.

As shown in fig. 5, the phosphor layer 312 conforms to the reflective surface 311A, and thus the phosphor layer 212 is also planar. In another embodiment, the phosphor layer 312 may also extend to cover the reflective surface 311B, or to cover the

reflective surfaces

311B and 311C.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A fixed wavelength conversion device, comprising:

a substrate, a fluorescent material layer and a heat dissipation element, wherein:

the substrate is provided with a first reflecting surface;

the fluorescent material layer is arranged on the first reflecting surface of the substrate; and

the heat dissipation element is connected to the substrate;

the base plate is fixed and non-rotatable.

2. A projector, comprising:

a first light source;

a light splitting element; and

the stationary wavelength conversion device according to claim 1, wherein said first reflective surface is disposed downstream of said first light source and said beam splitting element in the optical path.

3. A projector, comprising:

a first light source, a substrate, a fluorescent material layer, a light splitting element, a chassis and a heat dissipation element, wherein:

the fluorescent material layer is arranged on the substrate;

the light splitting element is arranged between the first light source and the optical path of the fluorescent material layer;

the fluorescent material layer is fixed in the base through the substrate; and

the heat dissipation element is thermally connected to the other surface of the substrate opposite to the fluorescent material layer.

4. The projector as claimed in claim 2 or 3, wherein the substrate further has a second reflective surface, the first reflective surface and the second reflective surface are continuous surfaces, and the second reflective surface turns toward the fluorescent material layer.

5. The projector as claimed in claim 4, wherein the substrate further has a third reflective surface, and the third reflective surface is connected to the first reflective surface via the second reflective surface.

6. The projector as claimed in claim 5, further comprising an optical element set disposed on the other side of the substrate opposite to the phosphor layer, the optical element set being connected to the substrate to define an enclosed space.

7. The projector of claim 2 or 3 further comprising a reflector cup, said reflector cup having a second reflective surface, said reflector cup having a recess, said recess having said substrate disposed therein.

8. The projector as defined in claim 7 wherein the reflector cup further comprises a third reflective surface disposed on an opposite side of the second reflective surface from the substrate, the third reflective surface being annular.

9. The projector as defined in claim 8 wherein the projector further comprises:

and the optical element group is arranged on the other side of the reflecting cup relative to the substrate and is connected with the reflecting cup to define a closed space.

10. The projector as defined in claim 7 wherein the projector further comprises a reflective ring attached to the other side of the reflective cup opposite the substrate, the reflective ring having a third reflective surface on an inner side thereof.