TWI402604B - Image projection system and a laser point detecting system therewith - Google Patents

Description

Image projection system and its spot detection system

The present invention relates to an image projection system, and more particularly to an image projection system that causes a plurality of screens to display laser spots and a spot detection system for use with the system.

In general briefing sessions, speakers often use projectors to project speech content on the screen and use laser pointers to correctly indicate where the speech is located. However, in large conferences, because there are a large number of people, if there is only one screen, only some people can see the speech briefing and cannot take care of all the audience or the audience. In order to solve this problem, two or more projectors are usually used to play the speech content in the prior art, so that the speech content is displayed on two or more screens to meet the large conference, so that the audience or The audience can see the speech on the screen.

Please refer to FIG. 1 , which is an architectural diagram of a conventional image projection system. For example, the conventional image projection system includes a computer host 100, an adapter device 102, a first projector 103, and a second projector 105. The computer host 100 is electrically connected to the first projector 103 and the second projector 105 through the switching device 102, so that the playing content in the computer host 100 can be simultaneously projected by the first projector 103 and the second projector 105. The first projector 103 projects the speech content on the first screen 104, and the second projector 105 projects the speech content on the second screen 106.

During the presentation, the presenter uses the laser pointer 107 to emit the laser light and displays a red spot 1071 on the first screen 104 to indicate the location of the speech content. The red spot 1071 is bright and clear and easy to recognize, making it easy for a viewer watching the first screen 104 to find the location of the content being spoken by the presenter. However, since the speaker can display the red spot on only one screen when using the laser pointer 107, the red spot cannot be displayed on all the screens, making it difficult for the viewer to view the screen other than the first screen 104. Follow up on the content of the speaker's presentation. In view of the above-mentioned shortcomings of the image projection system of the prior art, the inventors have developed the present invention in response to improvements in these disadvantages.

It is an object of the present invention to provide an image projection system that causes a plurality of screens to display laser spots.

It is still another object of the present invention to provide a spot detection system for use in the above image projection system.

The invention provides an image projection system, which comprises a computer host, an adapter device, a camera, a processor and two or more sets of projection systems. Each projection system includes a projector and a screen for projecting images by the projector. The host computer taps each projector through the switching device. The speaker uses a laser pointer to shoot the laser light and display a spot on the first screen. The camera described above is electrically connected to the first projection and captures an image projected by the first projector onto the first screen. The processor is connected between the camera and the switching device, and includes a spot positioning module and an image processing module. The spot positioning module receives the image from the camera and detects the position information of the spot on the first screen. The image processing module filters the image. The processor sends the position information of the spot and the filtered image to the switching device.

In a preferred embodiment of the invention, the image processing module includes a filter.

In a preferred embodiment of the present invention, the switching device includes an electrical connection determining module and a switching module, wherein the determining module is electrically connected to the processor, the switching module is coupled to the first projector, and Two projection electromechanical connections.

In a preferred embodiment of the present invention, each of the screens is a passive screen or an active screen, wherein the passive screen comprises a wall or a screen, and the active screen comprises a liquid crystal display or a monitor.

In a preferred embodiment of the present invention, each of the above screens is a liquid crystal display or a monitor, and the screen is electrically connected to the corresponding projector through a signal transmission interface.

In a preferred embodiment of the present invention, the first screen includes a function area to display a function icon, and the processor determines whether the position of the light spot on the first screen is located in the function area, and determines whether the light spot continues in the function area. Until a predetermined time.

In a preferred embodiment of the present invention, if the spot continues for a predetermined time in the function area, the processor transmits the position information to the host computer through the switching device, and the computer host determines the position information according to the light spot in the function area. Perform the corresponding function.

The invention also proposes another image projection system, which comprises a computer host, an adapter device, two or more sets of projection systems, two or more cameras and a processor. Each projection system includes a projector and a screen for projecting images by the projector. The host computer taps each projector through the switching device. The speaker uses a laser pointer to shoot the laser light and display a spot on the first screen. Each camera is mechanically coupled to a projection and captures the image that the projector projects onto the screen. The processor is connected to two or more cameras and is further connected to the adapter. The processor includes a spot positioning module and an image processing module, wherein the spot positioning module receives an image from the camera, detects position information of the spot on the first screen; and the image processing module filters the image. . The processor sends the position information of the spot and the filtered image to the switching device. The switching device comprises an electrical connection judging module and a switching module, wherein the judging module combines the image received from the processor with the speech content currently played by the computer host, and determines the position information and filtering received from the processor. The latter image is from the first camera; the switching device transfers the original speech content to the first projector connected to the first camera according to the determination result, and transfers the merged image to the projector other than the first projector. .

In addition, the present invention provides a light spot detection system for an image projection system, the image projection system including a computer host, an adapter device, and two or more sets of projection systems, wherein each projection system includes a A projector and a screen that projects images by the projector. The host computer is tapped to each projector through an adapter. The speaker uses the laser pointer to shoot the laser light and display a spot on the first screen. The spot detection system includes at least one camera and a processor, each camera being electrically connected to a projection and capturing an image projected by the projector onto the screen. The processor is coupled to the at least one camera and coupled to the switching device. The processor includes a spot positioning module and an image processing module. The spot positioning module receives images from the at least one camera and detects position information of the spot on the first screen. The image processing module filters the image, and the processor sends the position information of the spot and the filtered image to the adapter device.

In a preferred embodiment of the present invention, the switching device includes an electrical connection judging module and a switching module, wherein the judging module combines the image received from the processor with the speech content currently played by the computer host. And determining that the location information received from the processor and the filtered image are from the first camera, and the switching device transfers the original speech content to the first projector connected to the first camera according to the determination result, and divides the first projection The projector outside the machine transfers the merged image.

In a preferred embodiment of the invention, the image processing module includes a filter.

In a preferred embodiment of the present invention, the first screen includes a function area to display a function icon, and the processor determines whether the position of the light spot on the first screen is located in the function area, and determines whether the light spot continues in the function area. Until a predetermined time.

In a preferred embodiment of the present invention, if the spot continues for a predetermined time in the function area, the processor transmits the position information to the host computer through the switching device, and the computer host determines the position information according to the light spot in the function area. Perform the corresponding function.

The image projection system and the spot detection system thereof of the present invention detect the position of the spot by using a spot detection system connected to the projection system, and combine the spot information with the speech content and then transfer to the projector. Projection to display red spots on all screens. Therefore, the image projection system and the spot detection system thereof of the present invention are implemented in a large speech using a plurality of screens, and the speaker can display all the screens when the red light spot is displayed on only one screen using the laser pointer. This red spot allows viewers who watch all the screens to follow up on the content of the speaker's presentation.

The above and other objects, features and advantages of the present invention will become more <RTIgt;

Please refer to FIG. 2, which is a structural diagram of an image projection system according to a first preferred embodiment of the present invention. In the present embodiment, the presentation content is displayed on two screens as an example. The image projection system includes a computer host 10, an adapter device 20, a first projector 30, a first screen 31, a second projector 40, a second screen 41, a camera 50, a processor 60, and a laser pointer 70. The host computer 10 is electrically connected to the first projector 30 and the second projector 40 through the switching device 20, so that the playing content in the computer host 10 can be simultaneously projected by the first projector 30 and the second projector 40. . The first projector 30 projects the speech content on the first screen 31, and the second projector 40 projects the speech content on the second screen 41. In this embodiment, the first screen 31 and the second screen 41 may be passive screens, such as walls, screens, etc., which can be used to display images; the first screen 31 and the second screen 41 may also be active screens, such as liquid crystals. Display devices such as monitors and monitors. In the case of an active screen, the screen is electrically connected to the corresponding projector via a signal transmission interface.

The camera 50 is electrically connected to one of the projections and is used to capture a screen image corresponding to the projector. In the present embodiment, the camera 50 is connected to the first projector 30. The processor 60 is coupled between the camera 50 and the switching device 20. The laser pointer 70 emits laser light under the operation of the presenter and displays a red spot on the screen. In the present embodiment, the laser pointer 70 emits laser light under the operation of the presenter, and displays a red spot 71 on the first screen 31 for the speaker to indicate the speech content on the screen during the speech.

The switching device 20 includes a judging module 21 and a switching module 22 that are electrically connected to each other. The processor 60 includes a spot positioning module 61 and an image processing module 62 electrically connected to each other. The light spot positioning module 61, the image processing module 62, the determination module 21 and the switching module 22 are electrically connected in sequence, and the spot positioning module 61 is electrically connected to the camera 50, and the switching module 22 and the first projection are electrically connected. The machine 30 and the second projector 40 are electrically connected.

As shown in FIG. 2, the camera 50, the processor 60 and the determination module 21 described above constitute a spot detection system 11. Therefore, it can also be described that the image projection system of the present embodiment includes a computer host 10, a switching module 22, two or more sets of projection systems, and a spot detection system 11, wherein each set of projections The system includes a projector and a screen.

During the presentation, the host computer 10 outputs the speech content to the switching module 22 of the switching device 20, and the switching module 22 taps the speech content to the first projector 30. The first projector 30 projects the speech content onto the first screen 31. The presenter operates the laser pointer 70 during the presentation to display a red spot 71 on the first screen 31. The camera 50 captures the image on the first screen 31, that is, the content projected by the first projector 30, and transmits the captured image signal to the processor 60. After receiving the image signal from the camera 50, the spot positioning module 61 of the processor 60 recognizes the red spot 71 from the image and detects the position information of the red spot 71 on the first screen 31. The image processing module 62 filters the image signal to filter out the speech content and retain only the image of the red spot 71. For example, the image processing module 62 includes a filter to implement an image filtering function. The action of positioning the spot 71 by the spot positioning module 61 may be performed in succession or in synchronization with the action of filtering the image by the image processing module 62. Thereafter, the processor 60 transmits the position information of the spot 71 to the switching device 20.

The switching device 20 combines the position information of the light spot 71 received from the processor 60 with the speech content currently being played by the computer host 10, and acquires a speech content image with a red spot 71, and sends it to each projection. When the machine is projecting, the viewer can see the content position indicated by the laser pointer 70 by the viewer in front of each screen. In addition, in the present embodiment, the red spot 71 formed by the laser light emitted by the speaker using the laser pointer 70 is already present on the first screen 31. Therefore, the first projector 30 only needs to play the original speech content, and the transfer is performed. The device 20 does not need to send a speech content image with a red spot to the first projector 30.

In detail, in the present embodiment, the determination module 21 of the switching device 20 determines whether or not the aforementioned location information is received from the processor 60. If the determination module 21 determines that the location information is not received from the processor 60, the determination module 21 transmits the determination result to the control switching module 22, thereby controlling the switching module 22 to receive from the host computer. The original lecture content is provided directly to the second projector 40. From another point of view, once the judging module 21 receives the foregoing location information from the processor 60, the judging module 21 merges the received location information with the speech content currently played by the computer host 10, and merges The resulting speech content image with the red spot and the determination result are sent to the switching device 22. The switching device 22 transfers the original lecture content to the first projector 30 according to the received determination result, and transfers to each projector (in the present embodiment, the second projector 40) other than the first projector 30. The speech content image with the red spot obtained after the joining. In this way, the image displayed on the second screen 41 is the speech content with the red light spot emitted by the speaker using the laser pen 70. Therefore, the viewer in front of the second screen 41 can also see the same as the first screen 31. The speech content and the light point indicate the location.

In this embodiment, since only one projector is connected to the camera, the switching module 22 may default to connecting the camera to the first projector 30, and transfer the original speech content to the first projector 30 to the first projection. Each projector other than the machine 30 transfers the merged speech content image with a red spot. Therefore, the judging function in the judging module 21 can be omitted. If the image combining function is implemented by other circuits in the switching device 20 at the same time, the judging module 21 can be removed from the switching device 20. The switching module 22 directly determines how to transfer various images based on the location information transmitted by the processor 60. Further, in the present embodiment, two projectors are described as an example, but the number of projectors is not limited thereto, and two or more projectors may be used.

Please refer to FIG. 3 , which is a structural diagram of an image projection system according to a second preferred embodiment of the present invention. In the present embodiment, the presentation content is displayed on two screens as an example. The image projection system includes a computer host 10, a switching device 20, a first projector 30, a first screen 31, a second projector 40, a second screen 41, a first camera 51, a second camera 52, a processor 60, and a mine The indicator 70 is fired. The host computer 10 is electrically connected to the first projector 30 and the second projector 40 through the switching device 20, so that the playing content in the computer host 10 can be simultaneously projected by the first projector 30 and the second projector 40. The first projector 30 projects the speech content on the first screen 31, and the second projector 40 projects the speech content on the second screen 41. In this embodiment, the first screen 31 and the second screen 41 may be passive screens, such as walls, screens, etc., which can be used to display images; the first screen 31 and the second screen 41 may also be active screens, such as liquid crystals. Display devices such as monitors and monitors. In the case of an active screen, the screen is electrically connected to the corresponding projector via a signal transmission interface.

Each camera is electrically connected to one of the projectors and is used to capture images on the screen corresponding to the projector. In the present embodiment, the first camera 51 is connected to the first projector 30, and the second camera 52 is connected to the second projector 40. The first camera 51 and the second camera 52 are both electrically connected to the processor 60, and the processor 60 is further electrically connected to the switching device 20. The laser pointer 70 emits laser light under the operation of the presenter and displays a red spot on the screen. In the present embodiment, the laser pointer 70 emits laser light under the operation of the presenter, and displays a red spot 71 on the first screen 31 for the speaker to indicate the speech content on the screen during the speech.

The switching device 20 includes a judging module 21 and a switching module 22 that are electrically connected to each other. The processor 60 includes a spot positioning module 61 and an image processing module 62 electrically connected to each other. The light spot positioning module 61, the image processing module 62, the determination module 21 and the switching module 22 are electrically connected in sequence, and the spot positioning module 61 is electrically connected to the camera 50, and the switching module 22 and the first projection are electrically connected. The machine 30 and the second projector 40 are electrically connected.

From another point of view, the image projection system of the present embodiment can also be described as including a computer host 10, a switching module 22, two or more sets of projection systems, and a spot detection system, wherein Each projection system includes a projector and a screen. The spot detection system includes two or more cameras, a processor 60 and a determination module 21, and each camera is electrically connected to one of the projections. It is also used to capture images on the screen corresponding to this projector.

During the speech, the cameras 51 and 52 respectively capture the screens 31 and 41 in the absence of the red spot 71, but since the red spot 71 is not found, the switching module 22 in the switching device 20 will The speech content received by the computer host 10 is directly transferred to the first projector 30 and the second projector 40, whereby the first projector 30 projects the speech content on the first screen 31, and the second projector 40 will The speech content is projected on the second screen 41. When the presenter operates the laser pointer 70 to display a red spot 71 on the first screen 31 during the speech, the first camera 51 projects the image on the first screen 31, that is, the first projector 30. The content is captured, and the captured image signal is sent to the processor 60. After receiving the image signal from the first camera 51, the spot positioning module 61 of the processor 60 recognizes the red spot 71 from the image and detects the position information of the red spot 71 on the first screen 31. The image processing module 62 filters the image signal to filter out the content of the speech and retain only the image of the red spot 71. For example, the image processing module 62 includes a filter to implement an image filtering function. The action of positioning the spot 71 by the spot positioning module 61 may be performed in succession or in synchronization with the action of filtering the image by the image processing module 62. Thereafter, the processor 60 transmits the position information of the spot 71 and the filtered image to the switching device 20.

The switching device 20 combines the received image with the speech content currently played by the host computer 10 to obtain a speech content image with a red spot 71. If the speech content image with the red spot is sent to each projector for projection, the viewer can see the content position indicated by the laser pointer 70 by the viewer in front of each screen. In addition, in the present embodiment, the red spot 71 formed by the laser light emitted by the speaker using the laser pointer 70 is already present on the first screen 31. Therefore, the first projector 30 only needs to play the original speech content, and the transfer is performed. The device 20 does not need to send an image with a red spot to the first projector 30.

In detail, the determination module 21 of the switching device 20 combines the received image with the presentation content currently being played by the host computer 10, and determines which camera the received information received from the processor 60 is from. In the present embodiment, the determination result is that the first camera 51 captures the image projected by the first projector 30, and the determination module 21 transmits the combined image and the determination result to the switching device 22. The switching device 22 transfers the original lecture content to the first projector 30 according to the received determination result, and transfers to each projector (in the present embodiment, the second projector 40) other than the first projector 30. Engage the images behind. In this way, the image displayed on the second screen 41 is the speech content with the red light spot emitted by the speaker using the laser pen 70. Therefore, the viewer in front of the second screen 41 can also see the same as the first screen 31. The speech content and the light point indicate the location.

In the present embodiment, two sets of projection systems are taken as an example, but the number of projection systems is not limited thereto, and the projection system may be two or more, and similarly, the cameras are not limited to two, each set of projections. The system is connected to a camera, and each camera is electrically connected to the processor 60. In addition, the speaker can only use the laser pointer 70 to indicate the position of the speech content on one screen during the speech. Therefore, only the camera connected to the projector corresponding to the screen is photographed, and the other cameras have no shooting action, that is, the same Only one camera should be taken during the time.

In another embodiment, the image projection system of the present invention further has the function of, for example, when the presenter operates the laser pointer 70 to display a red spot 71 on the first screen 31 during the presentation. The first camera 51 captures the image on the first screen 31, that is, the content projected by the first projector 30, and transmits the captured image signal to the processor 60. The partial area is set as the function area 80 in the image on the first screen 31, and the icon representing the function button is displayed in the function area 80, such as turning the page forward, turning the page backward, enlarging the page, reducing the page, adjusting the volume, and the like. . After receiving the image signal from the first camera 51, the spot positioning module 61 of the processor 60 recognizes the red spot 71 from the image and detects the position information of the red spot 71 on the first screen 31, and It is further determined whether the position of the red spot 71 on the first screen 31 is within the functional area 80. If the position of the red spot 71 on the first screen 31 is outside the functional area 80, the next operation is the same as the above two embodiments.

If the position of the red spot 71 on the first screen 31 is within the functional area 80, the processor 60 further counts the time that the spot 71 continues within the functional area 80 if the spot 71 continues to reach a function within the functional area 80. The processor 60 transmits the location information to the switching device 20 for a predetermined time (e.g., 3 seconds). The switching device 20 transmits the position information of the light spot 71 received from the processor 60 to the computer host 10, and the computer host 10 performs a corresponding function according to the position information of the light spot 71 in the function area 80, such as turning the page forward, Scroll backwards, enlarge the page, zoom out, adjust the volume, or any action that can be set.

In short, in the present embodiment, the processor 60 of the image projection system further determines whether the spot 71 continues in the function area 80 for a predetermined time. If not, the other operations are the same as in the first and second embodiments. If the spot 71 continues to reach the predetermined time in the function area 80, the processor 60 transmits the position information to the computer host 10 through the switching device 20, and the computer host 10 performs corresponding operation according to the position information of the light spot 71 in the function area 80. The function. Therefore, when the speaker is operating, the function button icon in the function area 80 can be continuously indicated by the laser pointer 70 to realize the instantaneous remote control of switching of the playback content.

In summary, the image projection system and the spot detection system of the present invention detect the position of the spot by using a spot detection system connected to the projection system, and combine the spot information with the speech content. Connect to the projector for projection to display red spots on all screens. Therefore, the image projection system and the spot detection system thereof of the present invention are implemented in a large speech using a plurality of screens, and the speaker can display all the screens when the red light spot is displayed on only one screen using the laser pointer. This red spot allows viewers who watch all the screens to follow up on the content of the speaker's presentation.

While the present invention has been described in its preferred embodiments, the present invention is not intended to limit the invention, and the present invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the scope of the patent application.

100, 10. . . Computer host

102, 20. . . Adapter

103, 30. . . First projector

105, 40. . . Second projector

104, 31. . . First screen

106, 41. . . Second screen

107, 70. . . Laser pointer

1071, 71. . . light spot

11. . . Spot detection system

50. . . camera

51. . . First camera

52. . . Second camera

60. . . processor

61. . . Spot positioning module

62. . . Image processing module

twenty one. . . Judging module

twenty two. . . Switching module

80. . . Functional Area

1 is a block diagram of a conventional image projection system.

2 is a block diagram of an image projection system according to a first preferred embodiment of the present invention.

3 is a block diagram of an image projection system according to a second preferred embodiment of the present invention.

10. . . Computer host

11. . . Spot detection system

20. . . Adapter

twenty one. . . Judging module

twenty two. . . Switching module

30. . . First projector

40. . . Second projector

31. . . First screen

41. . . Second screen

50. . . camera

60. . . processor

61. . . Spot positioning module

62. . . Image processing module

70. . . Laser pointer

71. . . light spot

80. . . Functional Area

Claims (20)

An image projection system includes a computer host, an adapter device, and two or more sets of projection systems, wherein each projection system includes a projector and a screen projected by the projector, and the computer host passes the turn The pick-up device taps each projector, a laser pointer emits laser light and displays a light spot on a first screen, and the improvement is that the image projection system further includes a camera and a processor, and the camera and the first Projecting an electromechanical connection and capturing an image projected by the first projector onto the first screen, the processor being coupled between the camera and the switching device, the processor comprising a spot positioning module and an image processing a module, the spot positioning module receives an image from the camera, and detects position information of the spot on the first screen; the image processing module filters the image received by the spot positioning module; The device sends the spot information and the image obtained by filtering the position information of the first screen to the adapter device. The image projection system of claim 1, wherein the image processing module comprises a filter. The image projection system of claim 1, wherein the switching device comprises an electrical connection determining module and a switching module, wherein the determining module is electrically connected to the processor, and the switching module is Electrically coupled to the projection in each projection system. The image projection system of claim 1, wherein each of the screens is a passive screen or an active screen, the passive screen comprising a wall or a curtain, the active screen comprising a liquid crystal display or a monitor . The image projection system of claim 1, wherein the screen in each projection system is a liquid crystal display or a monitor, and the screen is electrically connected to the corresponding projector through a signal transmission interface. The image projection system of claim 1, wherein the screen in each projection system is a wall or a curtain. The image projection system of claim 1, wherein the first screen includes a function area to display a function icon, and the processor determines whether the position of the light spot on the first screen is located in the function area, and determines the light. Whether the point continues in the functional area for a predetermined time. The image projection system of claim 7, wherein if the spot continues to reach the predetermined time in the function area, the processor transmits the position information to the host computer through the switching device, and the computer host is according to the light spot. The location information in the function area performs the corresponding function. An image projection system includes a computer host, an adapter device, and two or more sets of projection systems, wherein each projection system includes a projector and a screen projected by the projector, and the computer host passes the turn The pick-up device taps each projector, a laser pointer emits laser light and displays a light spot on the first screen, and the improvement is that the image projection system further comprises two or more cameras and a processor, each of which The cameras are electrically connected to a corresponding one of the projectors and capture images projected by the projector to the screen. The processor is connected to the cameras and connected to the switching device. The processor includes a spot positioning module and An image processing module, the spot positioning module receives an image from one of the cameras, and detects position information of the spot on the screen; the image processing module filters the image; the processor uses the light The position information of the point and the filtered image are sent to the switching device together; the switching device includes an electrical connection determining module and a switching module, and the determining module will be The image received by the processor is merged with the speech content currently played by the host computer, and when it is determined that the position information of the spot received on the screen from the processor and the filtered image is from a first camera, The switching device transfers the speech content currently played by the computer host to a first projector connected to the first camera, and transfers the image obtained after the combining operation to the projector other than the first projector. The image projection system of claim 9, wherein the image processing module comprises a filter. The image projection system of claim 9, wherein the screen in each projection system is a passive screen or an active screen. The image projection system of claim 9, wherein the screen in each projection system is a liquid crystal display or a monitor, and the screen is electrically connected to the corresponding projector through a signal transmission interface. The image projection system of claim 9, wherein the screen in each projection system is a wall or a curtain. The image projection system of claim 9, wherein the first screen includes a function area to display a function icon, and the processor determines whether the position of the light spot on the first screen is located in the function area, and determines the light. Whether the point continues in the functional area for a predetermined time. The image projection system of claim 9, wherein if the spot continues to reach the predetermined time in the function area, the processor transmits the position information to the host computer through the switching device, and the computer host is in accordance with the light spot. The location information in the function area performs the corresponding function. A light spot detection system for an image projection system, the image projection system comprising a computer host, an adapter device and two or more sets of projection systems, wherein each projection system comprises a projector and is subjected to The projector projects an image of the screen, and the computer host taps the projectors through the switching device, a laser pointer emits the laser light and displays a light spot on the first screen; the spot detection system includes at least one a camera and a processor, each of the cameras being electrically coupled to a projection and capturing an image projected by the projector onto the screen; the processor being coupled to the at least one camera and coupled to the switching device, the processor including a a light spot positioning module and an image processing module, the processor receiving an image from the at least one camera, wherein the spot positioning module detects position information of the light spot on the first screen, and the image processing module The image is filtered; the processor sends the position information of the spot and the filtered image to the switching device. The optical spot detection system of claim 16, wherein the switching device comprises an electrical connection determining module and a switching module, and the converting device receives the image received from the processor and the The speech content currently played by the host computer is merged, and when the determining module determines that the position information received from the processor and the filtered image are from a first camera, the switching device is connected to the first camera. A projector transfers the speech content currently played by the computer host, and transfers the merged image to a projector other than the first projector. The spot detection system of claim 17, wherein the image processing module comprises a filter. The light spot detection system of claim 16, wherein the first screen includes a function area to display a function icon, and the processor determines whether the position of the light spot on the first screen is located in the function area, and It is judged whether the light spot continues in the functional area for a predetermined time. The spot detection system of claim 16, wherein if the spot continues to reach the predetermined time in the function area, the processor transmits the position information to the host computer through the switching device, and the computer host is based on the light. The location information in the function area performs the corresponding function.