Projection apparatus and phosphor wheel thereof

A phosphor wheel and a projection apparatus with the phosphor wheel are disclosed. A phosphor wheel includes a driving motor, a temperature interference element, a substrate and at least one light wavelength converting layer. The driving motor includes a motor body and a rotating member. The motor body drives the rotating member to rotate relative to the motor body along a rotation axis. The temperature interference element is connected with the rotating member and the substrate. The motor body drives the rotating member to rotate the temperature interference element and the substrate relative to the motor body. The substrate includes a first surface and a second surface disposed opposite to each other. The second surface is located between the first surface and the rotating member. The light wavelength converting layer is disposed on the first surface of the substrate.

CROSS-REFERENCE TO RELATED APPLICATION

THIS APPLICATION CLAIMS THE PRIORITY BENEFIT OF CHINA APPLICATION CN201821346900.1 FILED ON 2018 Aug. 21. THE ENTIRETY OF THE ABOVE-MENTIONED PATENT APPLICATION IS HEREBY INCORPORATED BY REFERENCE HEREIN AND MADE A PART OF THIS SPECIFICATION.

FIELD OF THE INVENTION

The invention relates to a projection apparatus and a phosphor wheel thereof, and more particularly to a projection apparatus and a phosphor wheel thereof including a temperature interference element.

BACKGROUND OF THE INVENTION

A projection apparatus is a device that projects an image onto a projection screen for presentation to a user. In order to achieve sufficient output brightness, the illumination system of the projection apparatus usually uses a laser light source and concentrates the generated laser on the phosphor layer of the phosphor wheel to generate sufficient fluorescence intensity output.

However, since heat is generated when the phosphor is irradiated by the laser to excite the fluorescence and the heat is easily conducted to the driving motor of the phosphor wheel, the driving motor may be damaged or have a reduced life by heat. Therefore, how to overcome the damage generated by the phosphor layer to the driving motor of the phosphor wheel is a focus of attention of those in the field.

The information disclosed in this “BACKGROUND OF THE INVENTION” section is only for enhancement understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Furthermore, the information disclosed in this “BACKGROUND OF THE INVENTION” section does not mean that one or more problems to be solved by one or more embodiments of the invention were acknowledged by a person of ordinary skill in the art.

SUMMARY OF THE INVENTION

The invention provides a phosphor wheel, which can reduce the damage of the heat generated by the light wavelength converting layer to the driving motor.

The invention further provides a projection apparatus, which can reduce the damage of the heat generated by the light wavelength converting layer to the driving motor.

Other objectives and advantages of the invention can be further illustrated by the technical features broadly embodied and described as follows.

In order to achieve one or a part or all of the above or other objectives, an embodiment of the invention provides a phosphor wheel, which includes a driving motor, a temperature interference element, a substrate and at least one light wavelength converting layer. The driving motor includes a motor body and a rotating member. The motor body drives the rotating member to rotate relative to the motor body along a rotation axis. The temperature interference element is disposed on the rotating member. The substrate is disposed on the temperature interference element. The temperature interference element is connected with the rotating member and the substrate. The motor body drives the rotating member to rotate the temperature interference element and the substrate relative to the motor body. The substrate includes a first surface and a second surface disposed opposite to each other. The second surface is located between the first surface and the rotating member. The light wavelength converting layer is disposed on the first surface of the substrate. The light wavelength converting layer is for converting an exciting beam incident on the light wavelength converting layer into a converted beam. The temperature interference element includes at least one spoiler.

In order to achieve one or a part or all of the above or other objectives, an embodiment of the invention provides a projection apparatus, which includes an illumination system, a light valve and a projection lens. The illumination system is for providing an illumination beam. The light valve is disposed on a transmission path of the illumination beam to convert the illumination beam into an image beam. The projection lens is disposed on a transmission path of the image beam. The illumination system includes an exciting light source and the aforementioned phosphor wheel. The exciting light source is for providing an exciting beam. The phosphor wheel is disposed on a transmission path of the exciting beam. The at least one light wavelength converting layer of the phosphor wheel is for converting the exciting beam into the converted beam. The illumination system includes the converted beam and the exciting beam.

In order to achieve one or a part or all of the above or other objectives, an embodiment of the invention provides a phosphor wheel, which includes a driving motor, a temperature interference element, a substrate and at least one light wavelength converting layer. The driving motor includes a motor body and a rotating member. The motor body drives the rotating member to rotate relative to the motor body along a rotation axis. The temperature interference element is disposed on the rotating member. The substrate is disposed on the temperature interference element. The temperature interference element is connected with the rotating member and the substrate. The motor body drives the rotating member to rotate the temperature interference element and the substrate relative to the motor body. The substrate includes a first surface and a second surface disposed opposite to each other. The second surface is located between the first surface and the rotating member. The at least one light wavelength converting layer is disposed on the first surface of the substrate. The light wavelength converting layer is for converting an exciting beam incident on the light wavelength converting layer into a converted beam. The substrate is disposed to surround the temperature interference element.

In order to achieve one or a part or all of the above or other objectives, an embodiment of the invention provides a projection apparatus, which includes an illumination system, a light valve and a projection lens. The illumination system is for providing an illumination beam. The light valve is disposed on a transmission path of the illumination beam to convert the illumination beam into an image beam. The projection lens is disposed on a transmission path of the image beam. The illumination system includes an exciting light source and the aforementioned phosphor wheel. The exciting light source is for providing an exciting beam. The phosphor wheel is disposed on a transmission path of the exciting beam. The at least one light wavelength converting layer of the phosphor wheel is for converting the exciting beam into the converted beam. The substrate is disposed to surround the temperature interference element.

The projection apparatus and the phosphor wheel thereof of the embodiment of the invention can reduce the impact of the heat generated by the light wavelength converting layer on the driving motor by providing a temperature interference element between the driving motor and the substrate, thereby preventing the driving motor from being damaged or having a reduced life by heat.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Refer toFIG.1.FIG.1is a schematic view of a projection apparatus according to an embodiment of the invention. The projection apparatus1includes an illumination system L, a light valve V and a projection lens P. The illumination system L is for providing an illumination beam IL. The light valve V is disposed on a transmission path of the illumination beam IL to convert the illumination beam IL into an image beam IM. The projection lens P is disposed on a transmission path of the image beam IM. The illumination system L includes an exciting light source E and a phosphor wheel10. The exciting light source E is for providing an exciting beam IE. The phosphor wheel10is disposed on a transmission path of the exciting beam IE. A light wavelength converting layer (not shown inFIG.1) of the phosphor wheel10is for converting the exciting beam IE into a converted beam (not shown inFIG.1), and the illumination beam IL may include the converted beam and the exciting beam IE. In addition, the image beam IM may become a projection beam IP after being projected by the projection lens P, and thereby forming an image frame on a projection surface.

The exciting light source E is, for example, a laser diode. In other embodiments, the exciting light source E is, for example, a light emitting diode (LED). In addition, the number of light sources is not limited in the invention. A single light source may be used if the light intensity thereof is strong enough, or, an array of exciting light sources E formed by a plurality of light sources may be used, and the invention is not limited thereto. The light valve V may be realized, for example, by a liquid crystal panel, a digital micro-mirror device (DMD), or a liquid crystal on silicon (LCoS) panel, and the invention is not limited thereto.

Refer toFIGS.2A-2C.FIGS.2A-2Care schematic views of the phosphor wheel10shown inFIG.1. Specifically,FIG.2Ais a perspective view of the phosphor wheel10from a viewing angle,FIG.2Bis a perspective view of the phosphor wheel10from another viewing angle, andFIG.2Cis a side view of the phosphor wheel10. As shown inFIG.2A, the phosphor wheel10of the embodiment includes a driving motor11, a temperature interference element13and a substrate15. As shown inFIG.2B, the phosphor wheel10further includes light wavelength converting layers1551and1553. The driving motor11includes a motor body111and a rotating member113. The motor body111drives the rotating member113to rotate relative to the motor body111along a rotation axis A (as shown inFIG.2C). The temperature interference element13is disposed on the rotating member113. The substrate15is disposed on the temperature interference element13, and the temperature interference element13is located between the substrate15and the motor body111on the rotation axis A. The motor body111drives the rotating member113along the rotation axis A to drive the temperature interference element13and the substrate15to rotate relative to the motor body111. In the embodiment, the area of the third surface131of the temperature interference element13is larger than 1.5 times the contact area of the rotating member113of the driving motor11and the third surface131, so as to effectively block the heat transferred from the substrate15to the motor11, but the invention is not limited thereto.

The substrate15includes a first surface151and a second surface153that are disposed opposite to each other. As shown inFIG.2C, the normal direction1511of the first surface151is parallel to the rotation axis A. The second surface153is located between the first surface151and the rotating member113. The light wavelength converting layers1551and1553are disposed on the first surface151of the substrate15. TakingFIG.2Bas an example, the light wavelength converting layers1551and1553are for converting the incident exciting beam IE into the converted beam IL1. When the motor body111drives the rotating member113to rotate the substrate15relative to the motor body111, the exciting beam IE incident on the phosphor wheel10can be irradiated on the light wavelength converting layers1551and1553in turn, and the converted beam IL1can be reflected by the substrate15. Thus, as shown inFIG.1, the illumination beam IL may include the converted beam IL1. Heat is generated when the light wavelength converting layer1551or1553converts the incident exciting beam IE into the converted beam IL1.

In addition, other optical elements such as a lens (not shown) may be disposed on the transmission path of the converted beam IL1for causing the converted beam IL1reflected by the phosphor wheel10to have a better light collecting effect.

In the embodiment, the temperature interference element13of the phosphor wheel10is exemplified by a heat insulating element, but the invention is not limited thereto. In other embodiments of the invention, the temperature interference element may be a heat dissipating element. In the embodiment, the temperature interference element13may, for example, include a material having a thermal conductivity k of less than 1 W/mK, such as a plastic or non-metal material. By the arrangement of the temperature interference element13having the heat insulating effect, the temperature interference element13can block the heat conduction between the substrate15and the driving motor11and reduce the degree of heat generated by the light wavelength converting layers1551and1553to the driving motor11, thereby preventing the driving motor11from being damaged or having a reduced life by heat.

In addition, the substrate15may be, for example, a heat dissipating element. The substrate15may, for example, include a material having a thermal conductivity k greater than 10 W/mK. By the arrangement of the substrate15having the heat dissipating effect, the heat generated on the light wavelength converting layer1551or1553can be conducted by the substrate15to reduce the amount of heat accumulated on the light wavelength converting layer1551or1553, and thereby reducing the possibility that the light wavelength converting layer1551or1553is damaged by heat and achieving the effect of heat dissipation.

Specifically, the temperature interference element13includes a third surface131and a fourth surface133that are disposed opposite to each other. The third surface131is located between the fourth surface133and the rotating member113, and the fourth surface133is located between the third surface131and the second surface153of the substrate15. In the embodiment, the area of the fourth surface133of the temperature interference element13is smaller than the area of the second surface153of the substrate15, but the invention is not limited thereto.

In addition, the temperature interference element13may further include, for example, at least one spoiler135. The spoiler135is disposed on the third surface131and protrudes from the third surface131. When the driving motor11drives the temperature interference element13and the substrate15to rotate, the spoiler135can move the air to generate an air flow to generate a heat dissipating effect, and thereby greatly reducing the impact of the heat generated by the optical wavelength converting layer1551or1553to the driving motor11. The structure and form of the spoiler135shown inFIG.2Aare merely illustrative and are not intended to limit the invention. The spoiler135is a protruding member, or the spoiler135is a recessing portion.

In the embodiment, the phosphor wheel10may further include, for example, an adhesive layer171. The adhesive layer171is disposed between the temperature interference element13and the rotating member113of the driving motor11, so that the temperature interference element13can be bonded to the rotating member113. The temperature interference element13is fixed to the rotating member113by the adhesion/gluing force of the adhesive layer171. The adhesive layer171may include, for example, a material having a lower thermal conductivity (k less than 1 W/mK) and a better heat insulating effect, so as to reduce the degree of the heat generated by the light wavelength converting layer1551or1553to the driving motor11. The adhesive layer171may include, for example, a silicone material, and the thickness of the adhesive layer171may be, for example, between 0.05 mm and 0.4 mm.

In addition, the substrate15may further include, for example, an optical zone157. The optical zone157is, for example, an aperture or provided with a light transmissive element (glass sheet). Beam can penetrate to the second surface153from the first surface151, that is, the optical zone157is for allowing the beam to penetrate the substrate15. When the substrate15is rotated relative to the motor body111, the exciting beam IE incident on the phosphor wheel10can be irradiated on the light wavelength converting layers1551,1553and the optical zone157in turns, so that a portion of the exciting beam IE can penetrate the phosphor wheel10. In other embodiments of the invention, the optical zone157may, for example, also be provided with a reflective element or a transflective element (not shown) so that a portion of the exciting beam IE may be reflected by or penetrate the phosphor wheel10.

The embodiment is exemplified by that the phosphor wheel10includes two light wavelength converting layers1551and1553; however, the number of light wavelength converting layers included in the phosphor wheel is not limited in the invention. The shape, size and position of the light wavelength converting layers1551and1553on the first surface151shown inFIG.2Bare only an example, and the structure and form of the motor body111and the rotating member113shown inFIG.2Aare also only an example, and the invention is not limited thereto.

FIG.3is a schematic view of a phosphor wheel according to another embodiment of the invention. Referring toFIG.3, in the embodiment, the phosphor wheel20includes a driving motor11, a temperature interference element13and a substrate15. The phosphor wheel20of the embodiment has a structure and function similar to the phosphor wheel10shown inFIGS.2A-2C. The main difference between this embodiment and the embodiment shown inFIGS.2A-2Cis: the phosphor wheel20further includes an adhesive layer173. The adhesive layer173is disposed between the temperature interference element13and the substrate15, so that the substrate15is bonded to the temperature interference element13. The adhesive layer173may include, for example, a material having a lower thermal conductivity (k less than 1 W/mK) and a better heat insulating effect, so as to reduce the degree of the heat generated by the light wavelength converting layer (not shown inFIG.3) to the driving motor11. The adhesive layer173may include, for example, a silicone material, and the thickness of the adhesive layer173may be, for example, between 0.05 mm and 0.4 mm.

FIG.4is a schematic view of a phosphor wheel according to another embodiment of the invention. Referring toFIG.4, in the embodiment, the phosphor wheel30includes a driving motor11, a temperature interference element13aand a substrate15. The phosphor wheel30of the embodiment has a structure and function similar to the phosphor wheel10shown inFIGS.2A-2C. The main difference between this embodiment and the embodiment shown inFIGS.2A-2Cis: the phosphor wheel30further includes an adhesive layer173a. The adhesive layer173ais disposed between the temperature interference element13aand the substrate15, so that the substrate15is bonded to the temperature interference element13a. The temperature interference element13aincludes a third surface131aand a fourth surface133athat are disposed opposite to each other. The third surface131ais located between the fourth surface133aand the rotating member113. The third surface131aand the fourth surface133aeach include a central region136aadjacent to the rotating member113and a peripheral region134aaway from the rotating member113, and the peripheral region134asurrounds the central region136a. In the embodiment, for example, the fourth surface133aincludes a central region136aadjacent to the rotating member113and a peripheral region134aaway from the rotating member113, and the peripheral region134asurrounds the central region136a. The adhesive layer173ais disposed between the peripheral region134aof the temperature interference element13aand the substrate15. Since the adhesive layer173ais disposed in the peripheral region134aof the temperature interference element13a, there is an air gap between the temperature interference element13aand the substrate15that does not include the adhesive layer173a, and air is present in the air gap. Thus, the degree of heat generated by the light wavelength converting layer (not shown inFIG.4) conducted to the driving motor11is further reduced. Therefore, the peripheral region134ais defined as a region including the adhesive layer173a, in other words, the central region136ais not provided with the adhesive layer173a. Further, the adhesive layer173amay be disposed in the entire peripheral region134ato bond the peripheral region134aof the temperature interference element13aand the region corresponding to the second surface153of the substrate15.

In addition, in the embodiment, the area and shape of the fourth surface133aof the temperature interference element13aare the same as those of the second surface153of the substrate15, but the invention is not limited thereto.

Further, in the embodiment, the adhesive layer173amay include, for example, a plurality of adhesive blocks1731a. The adhesive blocks1731aare disposed to be spaced from each between the peripheral region134aof the temperature interference element13aand the substrate15. The adhesive blocks1731amay, for example, have a predetermined distance from one another, such that there may be an air gap between the adhesive blocks1731a, wherein the air gaps allow air to flow. When the driving motor11drives the temperature interference element13aand the substrate15to rotate, the air gaps can effectively allow the heat dissipating airflow to flow, so that the heat generated by the substrate15can be taken away from the phosphor wheel30, and thereby achieving the heat dissipating effect and greatly reducing the impact of the heat generated by the light wavelength converting layer to the driving motor11. In the embodiment, the material included in the adhesive layer173amay be the same as or similar to the adhesive layer171or173of the phosphor wheel20, and no redundant detail is to be given herein.

In addition, the temperature interference element13amay further include, for example, at least one spoiler135a. The spoiler135ais disposed on the third surface131aand protrudes from the third surface131a. In other embodiments, the spoiler135ais disposed on the third surface131aand recessed on the third surface131a, or, a spoiler135aprotruding from the third surface131aand a spoiler135arecessing on the third surface131amay be both disposed on the same temperature interference element13a, but the invention is not limited thereto. In the embodiment, the spoiler135ais disposed, for example, in the peripheral region134aof the temperature interference element13a, but the invention is not limited thereto. The spoiler135acan generate heat dissipation when the driving motor11drives the temperature interference element13aand the substrate15to rotate. In addition, the temperature interference element13amay further include, for example, at least one heat dissipating hole137a. The heat dissipating hole137ais disposed in the central regions136aof the third surface131aand the fourth surface133a. The heat dissipating holes137apenetrates to the fourth surface133afrom the third surface131a. The heat dissipating hole137ais for allowing the airflow to penetrate the temperature interference element13a. The heat dissipating hole137acan generate heat dissipation when the driving motor11drives the temperature interference element13aand the substrate15to rotate.

In addition, in the embodiment, the temperature interference element13aof the phosphor wheel30is exemplified by a heat insulating member. The temperature interference element13amay, for example, include a material having a lower thermal conductivity. By the arrangement of the temperature interference element13ahaving a heat insulating effect, the temperature interference element13acan block heat conduction between the substrate15and the driving motor11.

FIG.5is a schematic view of a phosphor wheel according to another embodiment of the invention. Referring toFIG.5, in the embodiment, the phosphor wheel40includes a driving motor11, a temperature interference element13band a substrate15. The phosphor wheel40of the embodiment has a structure and function similar to the phosphor wheel30shown inFIG.4. The main difference between this embodiment and the embodiment shown inFIG.4is: the temperature interference element13bis exemplified by a heat dissipating element. The temperature interference element13bmay, for example, include a material having a thermal conductivity k greater than 10 W/mK, such as a metal. By the arrangement of the temperature interference element13bhaving a heat dissipating effect, the temperature interference element13bcan conduct the heat from the substrate15. The temperature interference element13bcan generate heat dissipation when the driving motor11drives the temperature interference element13band the substrate15to rotate. Further, by the arrangements of the spoiler135bin the peripheral region134bof the temperature interference element13band the heat dissipating hole137bin the central region136bof the temperature interference element13a, the heat from the substrate15to the temperature interference element13bis transferred to air by heat convection caused by the rotation of the temperature interference element13b.

In the embodiment, the structures of the third surface131b, the fourth surface133b, the central region136b, the peripheral region134b, the spoiler135b, and the heat dissipating hole137bof the temperature interference element13bare similar to those of the third surface131a, the fourth surface133a, the central region136a, the peripheral region134a, the spoiler135a, and the heat dissipating holes137aof the temperature interference element13ashown inFIG.4, and no redundant detail is to be given herein.

FIGS.6A-6Bare schematic views of a phosphor wheel according to another embodiment of the invention. Specifically,FIG.6Ais a perspective view of the phosphor wheel50, andFIG.6Bis a schematic cross-sectional view of the phosphor wheel50ofFIG.6Aat the rotation axis A when viewed in the direction D. Referring to FIGS.6A-6B, the phosphor wheel50includes a driving motor11a, a temperature interference element13cand a substrate15a. The driving motor11aincludes a motor body111aand a rotating member113a. The substrate15aincludes a first surface151aand a second surface153a. The substrate15amay, for example, include a structure similar to the aforementioned spoiler and heat dissipating hole, and the embodiment is exemplified by the heat dissipating hole. The temperature interference element13cincludes a first bonding structure1391and a second bonding structure1393. The temperature interference element13cis bonded to the rotating member113aby the first bonding structure1391, and the temperature interference element13cis bonded to the substrate15aby the second bonding structure1393. As such, the temperature interference element13cis fixed to the rotating member113a, the substrate15ais fixed to the temperature interference element13c, and the temperature interference element13cis rotated along the rotation axis A.

In the embodiment, the temperature interference element13cof the phosphor wheel50is exemplified by a heat insulating element. The temperature interference element13cmay, for example, include a material having a lower thermal conductivity. By the arrangement of the temperature interference element13chaving the heat insulating effect, the temperature interference element13ccan block the heat conduction between the substrate15and the driving motor11aand reduce the impact of the heat generated by the light wavelength converting layer (not shown inFIGS.6A and6B) to the driving motor11a, thereby preventing the driving motor11afrom being damaged or having a reduced life by heat. The effects and functions of the driving motor11aand the substrate15aare similar to those of the driving motor11and the substrate15described inFIGS.2A-2C, and no redundant detail is to be given herein.

Specifically, the rotating member113aincludes a convex portion1131and a flat portion1133. The surface of the convex portion1131of the rotary member113ahas a predetermined distance S from the second surface153aof the substrate15ain the direction of the rotation axis A, and the temperature interference element13cis a heat insulating member. As such, the impact of the heat generated by the light wavelength converting layer on the driving motor11acan be effectively reduced.

In addition, the phosphor wheel50may further include, for example, an adhesive layer175. The adhesive layer175is disposed between the second bonding structure1393and the substrate15a, so that the substrate15acan be bonded to the temperature interference element13c. The adhesive layer175may include, for example, a material having a lower thermal conductivity (k less than 1 W/mK) and a better heat insulating effect (e.g., a silica gel material), which can reduce the heat conduction from the light wavelength converting layer to the driving motor11a.

In the embodiment, the structure of the temperature interference element13cis exemplified by a hollow cylinder, and the first bonding structure1391and the second bonding structure1393are disposed at the two ends of the temperature interference element13crespectively. The substrate15ais disposed to surround the second bonding structure1393of the temperature interference element13c, and the first bonding structure1391is disposed to surround the convex portion1131of the rotating member113aand attach the planar portion1133of the rotating member113a, but the invention is not limited thereto. The structure and form of the first bonding structure1391and the second bonding structure1393of the temperature interference element13cshown inFIGS.6A-6Bare merely illustrative and are not intended to limit the invention. The structure and form of the first bonding structure1391are not limited as long as that the temperature interference component13cand the rotating member113acan be bonded, and the structure and form of the second bonding structure1393are not limited as long as that the temperature interference component13cand the substrate15acan be bonded. The rotating member113amay include a structure for bonding with the first bonding structure1391, and the substrate15amay include a structure for bonding with the second bonding structure1393.

FIG.7is a schematic cross-sectional view of a phosphor wheel according to another embodiment of the invention. Referring toFIG.7, in the embodiment, the phosphor wheel60includes a driving motor11b, a temperature interference element13dand a substrate15b. The driving motor11bincludes a motor body111band a rotating member113b. The substrate15bincludes a first surface151band a second surface153b. The phosphor wheel60of the embodiment has a structure and function similar to the phosphor wheel50shown inFIGS.6A-6B. The main difference between this embodiment and the embodiment shown inFIGS.6A-6Bis: the convex portion1131of the rotating member113bpenetrates the central hole159of the substrate15b. The temperature interference element13dis disposed to surround the convex portion1131of the rotating member113band is located at the convex portion1131and the periphery of the center hole159. By the arrangement of the convex portion1131of the rotating member113band the center hole159of the substrate15b, the temperature interference element13dis fixed to the rotating member113band the substrate15bis fixed to the temperature interference element13d. Further, the temperature interference element13ddoes not contact the flat portion1133of the rotating member113b, thus, the contact area is reduced and the heat conducted from the substrate15bto the driving motor11bcan be reduced.

In the embodiment, the temperature interference element13dof the phosphor wheel50is exemplified by a heat insulating element. The temperature interference element13dmay, for example, include a material having a lower thermal conductivity. By the arrangement of the temperature interference element13dhaving the heat insulating effect, the temperature interference element13dcan block the heat conduction between the substrate15band the driving motor11band reduce the impact of the heat generated by the light wavelength converting layer (not shown inFIG.7) to the driving motor11b, thereby preventing the driving motor11bfrom being damaged or having a reduced life by heat. The effects and functions of the driving motor11band the substrate15bare similar to those of the driving motor11and the substrate15described inFIGS.2A-2C, and no redundant detail is to be given herein. The structure and form of the convex portion1131of the rotating member113b, the flat portion1133of the rotating member113b, the central hole159of the substrate15b, and the temperature interference element13dshown inFIG.7are merely illustrative and are not intended to limit the invention.

In summary, the temperature interference element in the embodiment of the invention has a thickness range of at least greater than 0.2 mm and less than 10 mm, and the thermal conductivity k of the temperature interference element is less than 1 W/mK or t greater than 10 W/mK. In detail, when the temperature interference element has a thickness rang of at least greater than 0.2 mm and less than 10 mm and the thermal conductivity k of the temperature interference element is less than 1 W/mK, the product of the two ranges, for example, less than 0.01 (W/K). Therefore, the heat transferred from the substrate to the driving motor can be effectively blocked by the combination of the thickness and the thermal conductivity of the temperature interference element. Further, when the temperature interference element has a thickness range of at least greater than 0.2 mm and less than 10 mm and the thermal conductivity k of the temperature interference element is greater than 10 W/mK, the product of the two ranges, for example, at least greater than 0.002. Therefore, the heat transferred from the substrate to the temperature interference element can be effectively blocked by the combination of the thickness and the thermal conductivity of the temperature interference element.

The projection apparatus and the phosphor wheel thereof of the embodiment of the invention can reduce the impact of the heat generated by the light wavelength converting layer on the driving motor by providing a temperature interference element between the driving motor and the substrate, thereby preventing the driving motor from being damaged or having a reduced life by heat.