CN115453807A

CN115453807A - Light source module

Info

Publication number: CN115453807A
Application number: CN202111502539.3A
Authority: CN
Inventors: 胡嘉展
Original assignee: Delta Electronics Inc
Current assignee: Delta Electronics Inc
Priority date: 2021-06-08
Filing date: 2021-12-09
Publication date: 2022-12-09
Also published as: TWI788135B; TW202248739A

Abstract

A light source module comprises a light source, a fluorescent ring, a reflector and a driving device. The light source arrangement emits light. The fluorescent ring has an inner side. The reflector is configured to reflect light to form a spot on the inner side. The drive means is arranged to rotate the reflector such that the spot moves along a circular path on the inner side.

Description

Light source module

Technical Field

The present disclosure relates to a light source module, and more particularly, to a light source module for a projector.

Background

In recent years, optical projectors have been used in many fields, and the range of applications is expanding, for example, from consumer products to high-tech equipment. Various optical projectors are also widely used in schools, homes, and businesses to magnify and display a display pattern provided by a signal source on a projection screen.

For the light source configuration of an optical projector, it may be that the fluorescent material is driven to emit light by a solid-state laser light source. Therefore, the fluorescent material can be coated on the wheel disc, and the wheel disc is driven by the motor to rotate at a high speed, so that the energy of the laser light source received by the local fluorescent material in unit time is reduced, and the purpose of heat dissipation is achieved. However, as the brightness requirement of optical projectors increases, the heat dissipation requirement for fluorescent materials also becomes more severe.

Therefore, how to provide a light source module capable of solving the above problems has become one of the important research and development issues.

Disclosure of Invention

In view of the above, an objective of the present disclosure is to provide a light source module and a projector that can solve the above problems.

To achieve the above objective, according to one embodiment of the present disclosure, a light source module includes a light source, a fluorescent ring, a reflector, and a driving device. The light source arrangement emits light. The fluorescent ring has an inner side. The reflector is configured to reflect light to form a light spot on the inner side. The drive means is arranged to rotate the reflector such that the spot moves along a circular path on the inner side.

In one or more embodiments of the present disclosure, a fluorescent ring includes a ring body and a plurality of fluorescent blocks. The fluorescent blocks are arranged on the inner edge of the ring body along the annular path.

In one or more embodiments of the present disclosure, the ring body has a light-transmitting portion. The light-transmitting portion communicates the inner edge and the outer edge of the ring body and is arranged between the inner edge and the outer edge of the fluorescent block.

In one or more embodiments of the present disclosure, the fluorescent ring includes a ring body and a plurality of heat dissipation fins. The heat dissipation fins are arranged on the outer edge of the ring body.

In one or more embodiments of the present disclosure, the light source module further includes a housing. The shell is provided with a closed space. The reflector and the fluorescent block are positioned in the closed space.

In one or more embodiments of the present disclosure, the ring body forms a portion of the housing and has an upper opening and a lower opening that communicate. The shell further comprises a base and a light-transmitting cover body. The base covers the lower opening. The light-transmitting cover covers the upper opening and is optically coupled between the light source and the reflector.

In one or more embodiments of the present disclosure, the base is thermally connected to the ring body. The driving device is positioned in the closed space and arranged on the base.

In one or more embodiments of the present disclosure, the light source module further includes a dichroic mirror. The dichroic mirror is optically coupled between the light source and the reflector and is configured to reflect a portion of the light to the inner side to form another spot of light. The drive means is further arranged to rotate the dichroic mirror such that the further light spot moves along a further circular path on the inner side.

In one or more embodiments of the present disclosure, a fluorescent ring includes a ring body and a plurality of fluorescent blocks. The fluorescent blocks are arranged on the inner edge of the ring body along the other annular path.

In one or more embodiments of the present disclosure, the light spot and the other light spot are respectively located on opposite sides of the fluorescence ring.

To achieve the above objective, according to one embodiment of the present disclosure, a light source module includes a light source, a fluorescent ring, a reflector, a driving device, and a dichroic mirror. The light source is configured to emit excitation light in a first direction. The fluorescent ring has an inner side surface parallel to the first direction. The reflector is arranged in the center of the fluorescent ring and is obliquely arranged relative to the first direction. The reflector is configured to reflect the excitation light in a first direction and cause the excitation light to form a first spot on the inner side surface along a second direction. The drive device is configured to rotate the reflector such that the first spot moves along a circular path on the inner side. The dichroic mirror is disposed obliquely with respect to the first direction and is configured to transmit the excitation light and reflect the excited light. The first light spot is used for exciting the fluorescence ring and converting the fluorescence ring into excited light. The excited light can reach the dichroic mirror after being reflected by the reflector, and then leave the light source module after being reflected by the dichroic mirror.

In one or more embodiments of the present disclosure, the light source module further includes another dichroic mirror. The other dichroic mirror is disposed obliquely with respect to the first direction and is located in the center of the fluorescent ring and near the reflector. The other dichroic mirror is configured to reflect a portion of the excitation light to the inner side to form a second light spot and to transmit another portion of the excitation light to the reflector to form a first light spot. The driving device is configured to simultaneously rotate the other dichroic mirror and the reflector such that the first light spot and the second light spot move along different circular paths at different positions of the inner side surface simultaneously.

In one or more embodiments of the present disclosure, the fluorescent ring has two circles of fluorescent blocks corresponding to the first light spot and the second light spot, respectively. The two circles of fluorescent blocks are configured to convert the exciting light into different color lights respectively, and then the lights are reflected by the dichroic mirror to leave the light source module.

In summary, in the light source module of the present disclosure, the light generated by the light source is projected to the inner side surface of the stationary fluorescent ring along the annular path by the rotating reflector, so that different color lights can be generated by the fluorescent block of the fluorescent ring, and the color lights can be sequentially guided to the optical engine of the projector through the reflector and other optical components. Because the fluorescent ring is stationary, the fluorescent ring can be elastically extended to a heat dissipation structure (such as a heat dissipation fin, a heat sink, a heat pipe, a water cooling system, etc.) thermally connected to the fluorescent ring, and the heat generated by the light source on the fluorescent block can be conducted away faster than the conventional rotating fluorescent wheel. Therefore, the light source module can easily adopt a light source with higher power. Moreover, the rotating reflector can completely act in the closed space of the shell which is partially formed by the fluorescent ring, so that air dust can be effectively isolated, and the influence of the surfaces of the reflector and the fluorescent block on excitation efficiency due to pollution is avoided.

The foregoing is merely illustrative of the problems to be solved, solutions to problems, and effects produced by the present disclosure, and the details of which are set forth in the following description and the related drawings.

Drawings

In order to make the aforementioned and other objects, features, advantages and embodiments of the disclosure more comprehensible, the following description is given:

FIG. 1 is a schematic diagram illustrating a light source module and an optical engine in a projector according to an embodiment of the disclosure;

fig. 2 is a perspective view illustrating a partial assembly of the light source module in fig. 1;

fig. 3 is another perspective view illustrating a partial assembly of the light source module in fig. 1;

fig. 4 is a schematic diagram illustrating a light source module and an optical engine in a projector according to another embodiment of the disclosure.

The reference numbers illustrate:

100,100' projector

110: outer casing

200,200' light source module

210 light source

211 collimating lens

212a,212b,212c,212d, condenser lens

213a,213b and 213c dichroic mirrors

214 total reflection mirror

215 color adjusting wheel

216 integral column

220,220' light guide assembly

221,221' pipe fitting

222 reflector

223,223': lens

230,230' fluorescent ring

231,231' ring body

231a light transmission part

232,232a,232b,232c, 232'. Fluorescent block

233 transparent mirror

234 heat dissipation fins

240 drive device

241: motor

242 rotating shaft

250: base

251 stage

252 annular radiator

260 transparent cover

270,271 fan

280 optical sensor

A1 in a first direction

A2 the second direction

P, P' are light spots

S is a closed space

300 optical engine

Detailed Description

Embodiments of the present disclosure are disclosed in the drawings and, for purposes of explanation, numerous implementation details are set forth in the description below. It should be understood, however, that these implementation details are not to be interpreted as limiting the disclosure. That is, such implementation details are not necessary in some embodiments of the present disclosure. In addition, some conventional structures and components are shown in the drawings in a simplified schematic manner for the sake of simplifying the drawings.

Please refer to fig. 1. Fig. 1 is a schematic diagram illustrating a light source module 200 and an optical engine 300 in a projector 100 according to an embodiment of the disclosure. In the present embodiment, the projector 100 includes a light source module 200 and an optical engine 300. The light source module 200 is configured to generate different color lights. The optical engine 300 is configured to process the received color light into a projection image and project the projection image to a predetermined location (e.g., a projection screen).

Please refer to fig. 2 and fig. 3. Fig. 2 is a perspective view illustrating a partial assembly of the light source module 200 in fig. 1. Fig. 3 is another perspective view illustrating a partial assembly of the light source module 200 in fig. 1. As shown in fig. 1 to 3, in the present embodiment, the light source module 200 includes a plurality of light sources 210, a fluorescent ring 230, a reflector 222 and a driving device 240. The light source 210 is configured to emit excitation light in a first direction A1. The fluorescent ring 230 has an inner side. The inner side surface is parallel to the first direction A1. The reflector 222 is disposed in the center of the fluorescent ring 230 and is inclined with respect to the first direction A1. The reflector 222 is configured to reflect the excitation light in the first direction A1 and cause the excitation light to form a light spot P on the inner side surface along the second direction A2. The drive means 240 is arranged to rotate the reflector 222 such that the spot P moves along a circular path on the inner side. The first light spot is used to excite the fluorescence ring 230 and convert it into excited light.

As shown in fig. 1, in the present embodiment, the light source module 200 further includes a plurality of collimating lenses 211, condensing

lenses

212a and 212b, and a dichroic mirror 213a. The collimating lenses 211 are optically coupled with the light sources 210, respectively, to collimate the excitation light emitted by the light sources 210. The dichroic mirror 213a is disposed obliquely with respect to the first direction A1, and is configured to transmit excitation light and reflect the excited light converted by the fluorescence ring 230. After passing through the collimating lens 211, the excitation light emitted from the light source 210 passes through the

condenser lenses

212a and 212b and the dichroic mirror 213a in sequence and enters the reflector 222 through the upper opening of the fluorescent ring 230. In addition, the excited light converted by the fluorescence ring 230 can reach the dichroic mirror 213a after being reflected by the reflector 222, and then leave the light source module 200 after being reflected by the dichroic mirror 213a.

In some embodiments, the light source 210 is a blue semiconductor laser diode, for example, but the disclosure is not limited thereto.

As shown in fig. 2, in the present embodiment, the light source module 200 further includes a platform 251. The driving device 240 is disposed on the platform 251 and includes a motor 241 and a rotating shaft 242. The motor 241 is configured to rotate the shaft 242. The light source module 200 further includes a light guide element 220, wherein a reflector 222 is included in the light guide element 220. The light guide assembly 220 further includes a tube 221 and a plurality of lenses 223. The reflector 222 is obliquely disposed inside the pipe 221. The lens 223 is arranged and disposed at one end of the tube 221. The shaft 242 is connected to the tube 221, so that the motor 241 can rotate the light guide element 220 via the shaft 242. The reflector 222 disposed in the tube 221 is inclined at an angle of 45 degrees with respect to the rotation axis 242 of the rotation shaft 242, thereby horizontally reflecting the excitation light vertically incident from above.

In some embodiments, a fixing seat (not shown) for fixing the lens 223 may be disposed in the tube 221, or a positioning structure for fitting the lens 223 and the reflector 222 may be disposed on an inner wall of the tube 221.

In some embodiments, the light guiding element 220 may further include a balance block disposed at the other end of the tube 221 opposite to the lens 223, so that the center of gravity of the light guiding element 220 is located at the rotation axis of the rotation shaft 242. Therefore, the abrasion of the rotating shaft 242 due to the bias can be avoided, and the service life of the driving device 240 can be prolonged.

As shown in fig. 1 and 3, in the present embodiment, the fluorescent ring 230 includes a ring body 231, a plurality of fluorescent blocks 232 (specifically,

fluorescent blocks

232a,232b, and 232 c), and a transparent mirror 233. The fluorescent blocks 232a,232b,232c and the light-transmitting mirror 233 are arranged along a circular path at the inner edge of the ring body 231. The fluorescent blocks 232a,232b,232c are optical conversion elements and are configured to convert the excitation light horizontally reflected from the reflector 222 into different color lights, respectively. The colored light is collected by the lens 223 and then reflected by the reflector 222 along the original light path to leave the fluorescent ring 230.

In some embodiments, the

fluorescent blocks

232a,232b and 232c are three arc Glass fluorescent sheets (Phosphor in Glass), but the disclosure is not limited thereto, and in other embodiments, the fluorescent blocks may be formed by coating the fluorescent material on the ring body 231 and then sintering the coated fluorescent material. The glass fluorescent sheet has high heat resistance and high heat conduction characteristics of inorganic materials. In addition, the fluorescent powder excitation efficiency can be effectively improved by changing the refractive index of the glass.

As shown in fig. 1, in the present embodiment, the light source module 200 further includes a dichroic mirror 213b, a condensing lens 212c, a color adjustment wheel 215, and an integration rod 216. The color light exiting from the upper opening of the ring body 231 is reflected by the dichroic mirror 213a, and passes through the dichroic mirror 213b, the condensing lens 212c, the color adjustment wheel 215 and the integration rod 216 in sequence, and finally reaches the optical engine 300.

As shown in fig. 1 and 3, in the present embodiment, the ring body 231 has a light-transmitting portion 231a. The light-transmitting portion 231a communicates the inner edge and the outer edge of the ring body 231 and is arranged between two of the fluorescent blocks 232 (specifically, the

fluorescent blocks

232a,232 c). That is, the light-transmitting portion 231a is opposed to the light-transmitting mirror 233. As shown in fig. 1, when the light spot P moves to the transparent mirror 233, the excitation light sequentially passes through the transparent mirror 233 and the transparent portion 231a and leaves the fluorescence ring 230.

As shown in fig. 1, in the present embodiment, the light source module 200 further includes a plurality of condensing lenses 212d and a total reflection mirror 214. The excitation light leaving the fluorescent ring 230 through the light-transmitting portion 231a passes through the condensing lens 212d, is then reflected by the total reflection mirror 214 and the dichroic mirror 213b in sequence and guided to the color adjustment wheel 215, and then passes through the color adjustment wheel 215 and the integration rod 216 in sequence and reaches the optical engine 300. In summary, the excitation light emitted from the light source 210 may form a color light at one time and be reflected to the condensing lens 212c through the light path, and the excitation light may be transmitted to the condensing lens 212c through the light-transmitting portion 231a at another time. In other embodiments, the light-transmitting portion 231a may not be provided, and the excitation light may be supplemented in the optical path at the rear end, for example, a light source may be separately provided to be converged by the dichroic mirror 213 b.

As shown in fig. 3, in the present embodiment, the fluorescent ring 230 further includes a plurality of heat dissipation fins 234. The heat dissipation fins 234 are disposed on the outer edge of the ring body 231 and are configured to dissipate the heat generated by the light source 210 on the fluorescent block 232 to the air in a heat transfer manner.

As shown in fig. 1, in the present embodiment, the light source module 200 further includes a fan 270. The fan 270 may generate an air flow to rapidly remove heat from the heat sink fins 234.

As shown in fig. 1 to 3, in the present embodiment, the light source module 200 further includes an annular heat sink 252. The annular heat sink 252 is disposed between the platform 251 and the ring body 231 of the fluorescent ring 230, and is configured to rapidly conduct the heat generated by the light source 210 on the fluorescent block 232 from the ring body 231 to the platform 251 in a heat conduction manner.

In some embodiments, the annular heat sink 252 and the platform 251 may be combined to form a base 250 covering the lower opening of the ring body 231. In some embodiments, the base 250 is a unitary structure (i.e., the annular heat sink 252 is integrally formed with the platform 251).

In some embodiments, the material of at least one of the ring body 231, the annular heat sink 252, and the platform 251 of the fluorescent ring 230 comprises a metal, but the disclosure is not limited thereto.

With the above-described configuration, since the fluorescent ring 230 is stationary, the fluorescent ring 230 can be elastically expanded to thermally connect with a heat dissipation structure (such as heat dissipation fins, heat dissipation device, heat pipe, water cooling system, etc.), and the heat generated by the light source 210 on the fluorescent block 232 can be conducted away faster than the conventional rotating fluorescent wheel.

As shown in fig. 1, in the present embodiment, the light source module 200 further includes a light-transmitting cover 260. The light-transmitting cover 260 covers the upper opening of the ring body 231 and is optically coupled between the light source 210 and the reflector 222. Specifically, the light-transmitting cover 260 is located between the dichroic mirror 213a and the light guide 220. The ring body 231 of the fluorescent ring 230, the base 250 composed of the annular heat sink 252 and the platform 251, and the transparent cover 260 can form a housing with a closed space S. The light guide assembly 220, the fluorescent block 232 and the driving device 240 are located in the enclosed space S.

With the above-mentioned structure configuration, the rotating reflector 222 can completely operate in the enclosed space S, so that air dust can be effectively isolated, thereby preventing the surfaces of the reflector 222 and the fluorescent block 232 from being contaminated to affect the excitation efficiency.

As shown in fig. 1 and fig. 2, in the present embodiment, the light source module 200 further includes an optical sensor 280. The optical sensor 280 is disposed in the enclosed space S and configured to detect a rotation speed of the rotating shaft 242. Specifically, a mark may be formed on the surface of the rotating shaft 242, and the optical sensor 280 is used to sense the frequency or period of the mark, so as to know the actual rotating speed of the motor 241 and adjust and control the rotating speed.

Referring to fig. 4, a schematic diagram of a light source module 200 'and an optical engine 300 in a projector 100' according to another embodiment of the disclosure is shown. The embodiment is modified with respect to the fluorescent ring 230 in the embodiment shown in fig. 1, so that the descriptions of other similar components can refer to the related contents, and will not be repeated herein.

As shown in fig. 4, in the present embodiment, the light source module 200 'further includes another light guiding element 220'. The light guide assembly 220' includes a tube 221', a dichroic mirror 213c, and a plurality of lenses 223'. The light guide 220 'is located inside the inner side of the fluorescent ring 230' and fixed to a side of the light guide 220 away from the rotation shaft 242. The dichroic mirror 213c is disposed in the pipe 221 'obliquely to the first direction A1, and is located at the center of the fluorescent ring 230' and near the reflector 222. The lens 223 'is arranged and disposed at one end of the tube 221'. The motor 241 can simultaneously rotate the light guide assemblies 220,220' via the rotating shaft 242. The dichroic mirror 213c disposed inside the tube 221 'may be tilted at an angle of 45 degrees with respect to the rotation axis of the rotation shaft 242, so as to horizontally reflect a portion of the excitation light vertically incident from above to the inner side of the fluorescence ring 230' and allow another portion of the excitation light to pass through to the reflector 222 below (i.e., the dichroic mirror 213c is optically coupled between the light source 210 and the reflector 222). The excitation light reflected by the dichroic mirror 213c forms another light spot P 'on the inner side of the fluorescence ring 230', and the rotated light guide element 220 'moves the light spot P' along another circular path on the inner side. At this time, the light source module 200' forms two light spots P and P ' at different height positions on the inner side of the fluorescent ring 230' and moves along the circular path at the same time.

In addition, the fluorescence ring 230 'further comprises a plurality of fluorescence blocks 232'. The fluorescent blocks 232 'are arranged on the inner edge of the ring body 231' along the other annular path. In other words, the fluorescence ring 230 'of the present embodiment has two circles of fluorescence blocks 232 and 232'. The fluorescent block 232' is configured to convert the excitation light horizontally reflected by the dichroic mirror 213c into different color lights, respectively. The color light can be reflected by the dichroic mirror 213c along the primary light path and exit from the upper opening of the ring body 231'. The color light exiting from the upper opening of the ring body 231' is reflected by the dichroic mirror 213a, and passes through the dichroic mirror 213b, the condensing lens 212c, the color adjustment wheel 215 and the integration rod 216 in sequence, and finally reaches the optical engine 300.

In this embodiment, spots P and P 'are located on opposite sides of fluorescence ring 230', as shown in FIG. 4. Thus, the heat generated by the light source 210 on the fluorescent ring 230' can be more uniformly dispersed.

Compared to the embodiment shown in fig. 1, the fluorescent ring 230 'of the present embodiment does not include the transparent mirror 233, the ring body 231' does not include the transparent portion 231a, and the corresponding condensing lens 212d and the total reflection mirror 214 are also eliminated. In addition, the light source module 200 of the present embodiment further includes another fan 271. The two fans 270,271 are located on opposite sides of the fluorescent ring 230', and generate air flow to rapidly remove heat from the heat dissipating fins 234.

As will be apparent from the above detailed description of the embodiments of the present disclosure, in the light source module of the present disclosure, the light generated by the light source is projected to the inner side of the stationary fluorescent ring along the annular path by the rotating reflector, so that different color lights can be generated by the fluorescent blocks of the fluorescent ring, and the color lights can be sequentially guided to the optical engine of the projector through the reflector and other optical components. Because the fluorescent ring is stationary, the fluorescent ring can be elastically expanded to thermally connect with a heat dissipation structure (such as a heat dissipation fin, a heat sink, a heat pipe, a water cooling system, etc.), and the heat generated by the light source on the fluorescent block can be conducted away faster than the conventional rotating fluorescent wheel. Therefore, the light source module can easily adopt a light source with higher power. Moreover, the rotating reflector can completely act in the closed space of the shell which is partially formed by the fluorescent ring, so that air dust can be effectively isolated, and the influence on the excitation efficiency caused by the pollution of the surfaces of the reflector and the fluorescent block is avoided.

Although the present disclosure has been described with reference to specific embodiments, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the disclosure.

Claims

1. A light source module, comprising:

a light source configured to emit light;

a fluorescent ring having an inner side;

a reflector configured to reflect the light to form a light spot on the inner side; and

a drive device configured to rotate the reflector such that the spot moves along a circular path on the inner side surface.

2. The light source module of claim 1, wherein the fluorescent ring comprises:

a ring body; and

and the fluorescent blocks are arranged on the inner edge of the ring body along the annular path.

3. The light source module of claim 2, wherein the ring body has a light-transmitting portion that communicates between an inner edge and an outer edge of the ring body and is arranged between two of the plurality of phosphor blocks.

4. The light source module of claim 2, wherein the fluorescent ring comprises:

a ring body; and

and the plurality of radiating fins are arranged on the outer edge of the ring body.

5. The light source module of claim 2, further comprising a housing having an enclosed space, and the reflector and the plurality of phosphor blocks are located in the enclosed space.

6. The light source module of claim 5, wherein the ring body forms a portion of the housing and has communicating upper and lower openings, the housing further comprising:

a base covering the lower opening; and

and the light-transmitting cover body covers the upper opening and is optically coupled between the light source and the reflector.

7. The light source module of claim 6, wherein the base is thermally connected to the ring body, and the driving device is disposed on the base and located in the enclosed space.

8. The light source module of claim 1, further comprising a dichroic mirror optically coupled between the light source and the reflector and configured to reflect a portion of the light to the inner side to form another light spot, wherein the drive device is further configured to rotate the dichroic mirror such that the other light spot moves along another circular path on the inner side.

9. The light source module of claim 8, wherein the fluorescent ring comprises:

a ring body; and

a plurality of fluorescent blocks arranged along the other annular path at the inner edge of the ring body.

10. The light source module of claim 8, wherein the spot and the another spot are on opposite sides of the fluorescent ring.

11. A light source module, comprising:

a light source configured to emit excitation light in a first direction;

a fluorescent ring having an inner side surface parallel to the first direction;

a reflector disposed in the center of the fluorescent ring and tilted with respect to the first direction, the reflector configured to reflect the excitation light in the first direction and cause the excitation light to form a first spot on the inner side surface in a second direction;

drive means arranged to rotate said reflector such that said first spot moves along a circular path on said inner side; and

a dichroic mirror disposed obliquely with respect to the first direction and configured to transmit the excitation light and reflect an excited light,

the first light spot is used for exciting the fluorescence ring to be converted into the excited light, and the excited light can reach the dichroic mirror after being reflected by the reflector and then leaves the light source module after being reflected by the dichroic mirror.

12. The light source module of claim 11, further comprising another dichroic mirror disposed obliquely with respect to the first direction and centered on the fluorescence ring and proximate to the reflector, the another dichroic mirror configured to reflect a portion of the excitation light to the inner side to form a second light spot and transmit another portion of the excitation light to the reflector to form the first light spot, wherein the drive device is configured to simultaneously rotate the another dichroic mirror and the reflector such that the first light spot and the second light spot move along different circular paths at different positions of the inner side simultaneously.

13. The light source module of claim 12, wherein the fluorescent ring has two circles of fluorescent blocks corresponding to the first light spot and the second light spot, respectively, the two circles of fluorescent blocks being configured to convert the excitation light into different color lights, respectively, and then to be reflected by the dichroic mirror to exit the light source module.