TWI382269B - Projection apparatus - Google Patents

Description

Projection device

The present invention relates to a display device, and more particularly to a projection apparatus.

In general, the projection device projects the image generated by the light valve inside it onto the screen for viewing. If the infrared light source and the photodetector are used together, the projection device can simultaneously have image capturing or sensing. The ability to implement touch screen applications.

In detail, a projection device having a touch screen function usually has an optical engine, a plurality of charge coupled devices (CCDs), and an infrared light emitting system. The optical engine is adapted to provide an image beam, wherein the image beam is projected onto a screen on the object side to form an image frame. The infrared light emitting system is adapted to provide an infrared beam, wherein the infrared beam is transmitted toward the object side, and part of the infrared beam penetrates the screen. Therefore, when an object (for example, a finger) from the object side approaches the screen, a part of the infrared light beam passing through the screen is reflected by the object to form an object beam that is transmitted to the charge coupled element. In this way, the charge coupled device can detect the image of the object.

In a conventional projection device having a touch screen function, since the image beam and the infrared beam do not share the same transmission path and the transmission paths are independent of each other, the space of the optical engine, the charge coupled device, and the infrared light emitting system as a whole is made. The utilization rate is low, which makes it difficult to reduce the size of the projection device. In addition, since the transmission paths of these beams are independent of each other, the positions of the optical engine, the charge coupled device, and the infrared light emitting system are also difficult to correct.

Moreover, the infrared light beam emitted by the infrared light emitting system does not pass through the imaging lens and the beam shaping element, and thus cannot be uniformly projected on the screen, thus causing an infrared light beam in a certain area on the screen. The light intensity is higher, while the infrared beams in other areas have lower light intensities. Therefore, the conventional projection device must have a plurality of charge coupled elements, and the gain values of these charge coupled elements are different from each other. A charge-coupled component with a large gain value is used to detect a region of low light intensity on the screen, and a smaller gain value is used to detect a region with a higher light intensity.

In other words, if only one charge-coupled component is used, there is only one gain value, which results in imaging over-saturation on the charge-coupled component in the region where the light intensity is strong on the screen, and the region where the light intensity is weak on the charge-coupled component. The brightness of the image is too weak to be known. However, the use of multiple charge coupled components can cause the structure of the projection device to be too complex and bulky.

The present invention provides a projection apparatus capable of simultaneously providing a high-intensity image frame and a high-intensity invisible light beam, and can have a small volume.

An embodiment of the present invention provides a projection apparatus including an illumination system, a light valve, a reflective element, a wave plate, and a polarization splitting unit. The illumination system is adapted to provide an illumination beam, wherein the illumination beam comprises a visible beam and an invisible beam. The visible beam has a first polarization direction and the invisible beam has a second polarization direction. The light valve is disposed on the transmission path of the visible light beam and is adapted to convert the visible light beam into an image light beam, wherein the image light beam has a second polarization direction. The reflective element is disposed on the transmission path of the invisible beam and is adapted to reflect an invisible beam from the illumination system. The wave plate is disposed on the transmission path of the invisible light beam and is located between the illumination system and the reflective element, wherein the invisible light beam from the illumination system is sequentially reflected by the wave plate, reflected by the reflective element, and transmitted through the wave plate, and is reflected by the reflective element. And the invisible beam passing through the wave plate will have a first polarization direction. The polarization beam splitting unit is disposed on a transmission path of the illumination beam, the image beam, and the invisible beam from the wave plate. The polarization splitting unit transmits the visible light beam and the invisible light beam from the illumination system to the light valve and the wave plate, respectively, and transmits the image light beam from the light valve and the invisible light beam from the wave plate to an object side.

In an embodiment of the invention, the visible light beam having the first polarization direction can be reflected and transmitted by the polarization beam splitting unit to the light valve, and the invisible light beam having the second polarization direction can be transmitted to the wave plate through the polarization beam splitting unit. The invisible light beam from the wave plate having the first polarization direction can be reflected by the polarization beam splitting unit and transmitted to the object side. An image beam having a second polarization direction from the light valve can be transmitted to the object side through the polarization beam splitting unit.

In an embodiment of the invention, the visible light beam having the first polarization direction is transmitted through the polarization beam splitting unit to the light valve. The invisible light beam having the second polarization direction can be reflected by the polarization beam splitting unit and transmitted to the wave plate. An invisible light beam having a first polarization direction from the wave plate can be transmitted to the object side through the polarization beam splitting unit. The image beam from the light valve having the second polarization direction can be reflected by the polarization beam splitting unit and transmitted to the object side.

In an embodiment of the invention, the first polarization direction is substantially perpendicular to the second polarization direction. The wave plate is, for example, a quarter-wave plate. The polarization beam splitting unit is, for example, a wire grid type PBS. In an embodiment of the invention, the projection device may further include a first cymbal and a second cymbal. The first one bears the second one. The polarization beam splitting unit is a polarization beam splitting film, and the polarization beam splitting film is located at an interface between the first turn and the second turn.

In an embodiment of the invention, the projection device may further comprise a projection lens. The projection device is disposed on the transmission path of the image beam and the invisible beam, and is located between the polarization beam splitting unit and the object side. In an embodiment of the invention, the projection device may further include a portion of the penetrating partial reflector and a photodetector. The partially penetrating partial reflector is disposed on the transmission path of the image beam and the invisible beam, and is located between the projection lens and the polarization beam splitting unit. The partially penetrating partial reflector is adapted to transmit the image beam and a portion of the invisible beam to the object side. An object on the object side reflects at least a portion of the portion of the invisible beam that is transmitted to the object side to form an object beam. Partially penetrating the partial reflector allows a portion of the object beam from the object to be transmitted to the photodetector. The image beam from the polarization beam splitting unit and a portion of the invisible beam may be transmitted to the object side by partially penetrating the partial reflector. A portion of the object beam from the object can be reflected by the partially transmissive partial reflector to the photodetector. In an embodiment of the invention, the projection device may further comprise an imaging lens. The imaging lens is disposed on a transmission path of a part of the object beam from the partially penetrating partial reflector, and is located between the partially penetrating partial reflector and the photodetector.

In one embodiment of the invention, the photodetector is, for example, a charge coupled device (CCD) or a complementary metal oxide semiconductor sensor (CMOS sensor). The invisible beam is, for example, an infrared beam. The illumination system can include at least one visible light source, an invisible light source, and a light homogenizing element. The visible light source is adapted to provide a visible light beam. The invisible light source is adapted to provide an invisible beam. The light homogenizing element is disposed on a transmission path of the visible beam and the invisible beam. The visible beam and the invisible beam can be transmitted to the polarization beam splitting unit through the light homogenizing element.

In an embodiment of the invention, the projection device further includes a control unit, and the number of visible light sources is plural, and the visible light sources are a plurality of visible light sources having different illumination colors. The control unit is electrically connected to the invisible light source and the visible light source to drive the visible light sources to be sequentially extinguished, and to drive the invisible light source to continuously provide an invisible light beam. In an embodiment of the invention, the projection device may further comprise a dichroic mirror. The dichroic mirror is disposed on the visible beam and the invisible beam transmission path. The dichroic mirror is adapted to transmit an invisible light beam from the invisible light source and a visible light beam from the visible light source to the light homogenizing element. The light uniform element is, for example, an optical integration column or a lens array. The visible light source and the invisible light source are each, for example, a laser diode.

The projection device of the embodiment of the present invention provides a visible light beam having a first polarization direction and an invisible light beam having a second polarization direction, and uses a reflective element, a wave plate, and a polarization beam splitting unit to form an image beam having different polarization directions and See the beam so that the image beam and the invisible beam share part of the transmission path. Therefore, the space utilization of each component in the projection device is high, which enables the projection device to have a small volume. In addition, in the projection apparatus of the embodiment of the present invention, since the visible light beam and the invisible light beam do not pass through the light valve at the same time, but are respectively transmitted to the object side by the action of the light valve and the reflective element, the illumination system It is not necessary to alternate the visible beam with the invisible beam. In this way, the illumination system can increase the time of the visible light beam and the invisible light beam at any time interval, so that the brightness of the image projected by the projection device can be improved, and the intensity of the invisible light beam can be improved.

The above described features and advantages of the invention will be apparent from the following description.

The following description of the various embodiments is provided to illustrate the specific embodiments of the invention. The directional terms mentioned in the present invention, such as "upper", "lower", "front", "back", "left", "right", etc., are merely directions referring to the additional drawings. Therefore, the directional terminology used is for the purpose of illustration and not limitation.

First embodiment

1 is a schematic structural view of a projection apparatus according to a first embodiment of the present invention, and FIG. 2A is a schematic diagram of the illumination system illustrated in FIG. 1. Referring to FIG. 1 and FIG. 2A , the projection apparatus 100 of the embodiment includes an illumination system 110 , a light valve 120 , a reflective component 130 , a wave plate 140 , and a polarization splitting unit 150 . The illumination system 110 is adapted to provide an illumination beam 112, wherein the illumination beam 112 includes a visible beam 112a and an invisible beam 112b. Visible beam 112a has a first polarization direction P1 and non-visible beam 112b has a second polarization direction P2. The reflective element 130 is, for example, a mirror.

The infrared beam will be exemplified by the invisible beam 112b. In other embodiments, it may also be a wavelength range using other invisible light, such as far-infrared light.

In the present embodiment, the illumination system 110 includes at least one visible light source 114, an invisible light source 116, and a light homogenizing element 118. In particular, illumination system 110 can include a plurality of visible light sources 114 that emit different colors, as depicted in Figure 2A. The visible light source 114 is adapted to provide a visible light beam 112a, while the invisible light source 116 is adapted to provide an invisible light beam 112b. The light homogenizing element 118 is disposed on the transmission path of the visible light beam 112a and the invisible light beam 112b, wherein the visible light beam 112a and the invisible light beam 112b are transmitted to the polarization beam splitting unit 150 through the light uniformizing element 118, as shown in FIG.

The illumination system 110 of the present embodiment uses the visible light source 114 of three different wavelength ranges as an implementation example, such as a red light source, a green light source, and a blue light source, and is disposed on the transmission path of the visible beam 112a and the invisible beam 112b. A plurality of dichroic mirrors 119 are provided to pass the invisible light beam 112b from the invisible light source 116 to the visible light beam 112a from the visible light source 114 to the light homogenizing element 118. In other words, the present embodiment utilizes the beam splitter 119 to combine the visible light beam 112a and the invisible light beam 112b of three different wavelength ranges. In this embodiment, the projection device 100 further includes a control unit 192 electrically connected to the invisible light source 116 and the visible light source 114 to drive the visible light sources 114 to be sequentially extinguished, and to drive the invisible light source 116 continuously. See the beam. 2B is a diagram showing the turn-on time distribution of the visible light source and the invisible light source in FIG. 2A in one cycle time. As can be seen from FIG. 2B, the invisible light source 116 is continuously turned on in a cycle time, and the red light source, the green light source, and the blue light source are each turned on in a dedicated time interval during a period of time, and are not exclusive. Closed within the time interval.

In the present embodiment, the visible light source 114 and the invisible light source 116 are each, for example, a laser diode to provide a visible light beam 112a having a first polarization direction P1 and an invisible light beam 112b having a second polarization direction P2, respectively. In other possible embodiments, it is also possible to use a non-polarized light source, and then use a polarization conversion system (PCS) or a polarizer to make the light beam have the above-mentioned polarization. In the present embodiment, the light homogenizing element 118 is used, for example, to homogenize the visible light beam 112a and the invisible light beam 112b passing therethrough, wherein the light homogenizing element 118 can be an optical integrating column or a lens array.

Referring again to FIG. 1, the light valve 120 is disposed on the transmission path of the visible light beam 112a and is adapted to convert the visible light beam 112a into an image light beam 112c, wherein the image light beam 112c has a second polarization direction P2. In the present embodiment, the light valve 120 is, for example, a liquid-crystal-on-silicon panel (LCOS panel) or other suitable light valve.

The reflective element 130 is disposed on the transmission path of the invisible light beam 112b and is adapted to reflect the invisible light beam 112b from the illumination system 110; the wave plate 140 is disposed on the transmission path of the invisible light beam 112b and is located in the illumination system 110 and the reflective element 130. Between, wherein the invisible light beam 112b from the illumination system 110 passes through the wave plate 140, is reflected by the reflective element 130, passes through the wave plate 140 again, and is reflected by the reflective element 130 and passes through the invisible light beam 112b of the wave plate 140. There is a first polarization direction P1 as shown in FIG. In the present embodiment, the wave plate 140 is, for example, a quarter-wave plate.

The polarization beam splitting unit 150 is disposed on the transmission path of the illumination beam 112, the image beam 112c, and the invisible light beam 112b from the wave plate. The polarization splitting unit 150 transmits the visible light beam 112a and the invisible light beam 112b from the illumination system 110 to the light valve 120 and the wave plate 140, respectively, and causes the image light beam 112c from the light valve 120 and the invisible light beam from the wave plate 140. 112b is delivered to an object side as shown in FIG. In the present embodiment, the polarization beam splitting unit 150 is, for example, a wire grid type PBS. In detail, the polarization splitting unit 150 may reflect the light beam having the first polarization direction P1 and may pass the light beam having the second polarization direction P2 therethrough. In other words, the visible light beam 112a having the first polarization direction P1 is reflected and transmitted to the light valve 120 by the polarization beam splitting unit 150, and the invisible light beam 112b having the second polarization direction P2 is transmitted to the wave plate 140 through the polarization beam splitting unit 150. ,As shown in Figure 1.

In addition, since the polarization beam splitting unit 150 has an optical property that can reflect the light beam having the first polarization direction P1 and let the light beam having the second polarization direction P2 pass therethrough, the invisible from the wave plate 140 having the first polarization direction P1 The light beam 112b is reflected by the polarization beam splitting unit 150 and transmitted to the object side, and the image light beam 112c having the second polarization direction P2 from the light valve 140 passes through the polarization beam splitting unit 150 and is transmitted to the object side. In this embodiment, the first polarization direction P1 is substantially perpendicular to the second polarization direction P2, wherein the first polarization direction P1 may be S polarization and the second polarization direction P2 may be P polarization. Of course, in other possible implementations, the first polarization direction P1 may be P polarization, and the second polarization direction P2 may be S polarization, which is determined by the user's needs and design. For example, the first polarization direction P1 is S polarization, and the second polarization direction P2 is P polarization, but is not limited thereto.

Referring to FIG. 3, in another embodiment, the polarization splitting unit 150 of the projection device 100' adopts a polarization beam that can reflect a light beam having a second polarization direction P2 and can pass a light beam having a first polarization direction P1 therethrough. In the case of the plate, the positions of the light valve 120, the wave plate 140 and the reflection surface 130 are reversed to form a pattern as shown in FIG. As such, the visible light beam 112a from the illumination system 110 having the first polarization direction P1 will pass through the polarization beam splitting unit 150 and be transmitted to the light valve 120, while the invisible light beam from the illumination system 110 having the second polarization direction P2. 112b is reflected by the polarization beam splitting unit 150 and transmitted to the wave plate 140, as shown in FIG.

Similarly, since the polarization splitting unit 150 has an optical property that can reflect the light beam having the second polarization direction P2 and pass the light beam having the first polarization direction P1 therethrough, the first polarization direction P1 from the wave plate 140 is not available. See that the light beam 112b passes through the polarization beam splitting unit 150 and is transmitted to the object side, and the image light beam 112c from the light valve 120 having the second polarization direction P2 is reflected by the polarization beam splitting unit 150 and transmitted to the object side, as shown in FIG. Painted.

Referring to FIG. 1 and FIG. 3, it can be seen that the projection device 100, 100' can be based on the polarization direction of the visible beam 112a and the invisible beam 112b and the polarization splitting characteristic of the polarization beam splitting unit 150 (for example, the first polarization can be made). The light beam of the direction P1 passes, and the light beam of the second polarization direction P2 is reflected; or the light beam of the second polarization direction P2 is passed, and the light beam of the first polarization direction P1 is reflected, and the light valve 120, the wave can be The sheet 140 is designed differently from the reflective element 130, as illustrated in Figures 1 and 3. In addition, the optical beam 112c from the light valve 120 and the invisible light beam 112b from the wave plate 140 can be shared between the polarization beam splitting unit 150 and the object side, regardless of the optical design shown in FIGS. 1 and 3. The same delivery path.

Referring to FIG. 1 , in the embodiment, the projection device 100 further includes a projection lens 160 disposed on the transmission path of the image beam 112 c and the invisible beam 112 b and located between the polarization beam splitting unit 150 and the object side. In addition, the projection device 100 may further include a portion of the penetrating partial reflector 170 and a photodetector 180. The partially penetrating partial reflector 170 is disposed on the transmission path of the image beam 112c and the invisible beam 112b, and is located between the projection lens 160 and the polarization beam splitting unit 150, wherein the partially penetrating partial reflector 170 is adapted to enable the image beam 112c and A portion of the invisible light beam 112b is transmitted to the object side, and an object 60 (such as a finger) on the object side reflects at least a portion of the portion of the invisible light beam 112b transmitted to the object side to form an object beam 112d, wherein the object beam 112d The wavelengths used for the invisible beam 112b are shown in Figures 1 and 3. In addition, a portion of the object beam 112d from the object 60 is transmitted to the photodetector 180 by the partially transmissive partial reflector 170. In this embodiment, the partially penetrating partial reflector 170 is capable of reflecting part of the invisible light and is capable of allowing part of the invisible light to pass through, but is capable of transmitting visible light. Therefore, the image beam 112c and the partially invisible light beam 112b from the polarization beam splitting unit 150 are transmitted to the object side by partially penetrating the partial reflector 170, and the partial object beam 112d from the object 60 is partially penetrated by the partial reflector. 170 is reflected to photodetector 180.

In general, if the illumination system is to provide both a visible beam and an invisible beam, a time sequence can be used to sequentially provide the visible beam and the invisible beam. In other words, the visible light source and the invisible light source are sequentially extinguished to provide a visible beam and an invisible beam at different time intervals. However, if this method is used, the brightness of the image frame when the projection device is projected is lowered, because the visible light beam cannot be simultaneously provided when the invisible light beam is supplied, thereby shortening the irradiation time of the visible light beam. , thereby reducing the projection effect of the projection device. In addition, when the visible light beam is provided, the invisible light beam cannot be simultaneously provided, thereby reducing the sensitivity in image capturing or sensing.

In the projection apparatus 100 of the present embodiment, since the visible light beam 112a and the invisible light beam 112b do not simultaneously pass through the light valve, but are transmitted to the object side by the action of the light valve 120 and the reflective element 140, respectively, the illumination The system does not have to alternate the visible beam 112a with the invisible beam 112b. It can be seen from FIG. 2A that in the present embodiment, the visible light source 114 and the invisible light source 116 (as shown in FIG. 2B) can be simultaneously turned on without being alternately extinguished. In this way, the time during which the illumination system 110 emits the visible light beam 112a and the invisible light beam 112b can be increased in any time interval, so that the brightness of the image image projected by the projection device 100 can be improved, and the invisible light beam can be raised. Strength of. When the intensity of the invisible light beam is increased, the photodetector 180 also has a better effect in image capturing and sensing.

In addition, the projection lens 160 can be designed for the wavelength of the image beam 112c, the angle of the light cone, and the size of the light valve 120, so that the projection device 100 can be optimally designed according to the needs of the user when performing image projection. And make it have better display quality. In addition, the projection lens 160 may also be a shared lens when the projection device 100 performs image projection or image detection. For example, when the projection device 100 performs image projection, the image light beam 112c from the light valve 120 sequentially passes through the polarization beam splitting unit 150, the partially penetrating partial reflector 170, and the projection lens 160, and finally the projection lens 160. Projected onto a screen 70 on the object side to form an image frame.

In this embodiment, the projection apparatus further includes an imaging lens 190 disposed on the transmission path of the partial object beam 112d from the partially penetrating partial reflector 170, and located at the partially penetrating partial reflector 170 and the photodetector 180. between. Specifically, when the projection device 100 is performing image detection, a part of the object beam 112d from the object side of the object side sequentially passes through the projection lens 160, is partially reflected by the partial reflection reflector 170, and penetrates the imaging lens 190. It is passed to the photodetector 180. In addition, the imaging lens 190 can be designed for the wavelength of the object beam 112d, the size of the photodetector 180, and the cone angle of the detected object beam 112d, so that the projection device 100 can have better sensing quality when sensing the image. . In this embodiment, the photodetector 180 is, for example, a charge coupled device (CCD) or a complementary metal oxide semiconductor sensor (CMOS sensor).

In addition, in the embodiment, the projection device 100 can simultaneously perform image projection and image detection, and the object 60 is, for example, a user's finger. When the finger moves to any position in the image frame on the screen 70, the photodetector 180 can sense the image of the finger. The signal of the finger image can be transmitted to the computer electrically connected to the projection device 100, and the computer can determine the position of the finger image relative to the image frame. In this way, the user can operate the computer by moving the finger to a specific location on the screen 70. The screen 70 is, for example, an atomized planar structure on a light transmissive tabletop, and the projection device 100 projects the image frame onto the light transmissive desktop, and the user can operate the computer by moving the finger to a specific location on the desktop.

Since the projection apparatus 100 of the present embodiment simultaneously supplies the visible light beam and the invisible light beam having different polarization directions by the illumination system 110, and uses the polarization beam splitting unit 150 to perform combining and splitting, the image light beam 112c and the invisible light beam 112b. The transmission path between the polarization beam splitting unit 150 and the object side may be shared, and the image beam 112c, the invisible beam 112b and the object beam 112d may share a transmission path partially penetrating the partial reflector 170 to the object side, and thus the projection device 100 The space utilization of each component is better, so the volume of the projection device 100 can be effectively reduced.

Further, in the projection apparatus 100 of the present embodiment, since the invisible light beam 112b and the image light beam 112c are transmitted to the object side following the same transmission path, and are also refracted by the projection lens 160, the invisible light beam 112b can be uniformly It is illuminated on the screen 70. In addition, the object beam 112d and the invisible beam 112b are opposite in the direction of transmission between the partially penetrating partial reflector 170 and the object side, and the transmission path is overlapped, and the object beam 112d and the invisible beam 112b are subjected to the imaging lens 190 as well. The refraction of the screen 70 is uniform on the photodetector 180. Therefore, the projection device 100 only needs to detect the object beam 112d by using a gain value by a single photodetector 180. In this way, the plurality of photodetectors are not required as in the conventional projection device, and thus the projection device 100 of the embodiment can further have a small volume.

Second embodiment

4 is a schematic structural view of a projection apparatus according to a second embodiment of the present invention. Referring to FIG. 4, the projection device 200 of the present embodiment is similar to the projection device 100 of the previous embodiment, and the same components are denoted by the same symbols, but the difference is that the projection device 200 further includes a first frame 212 and a second portion.稜鏡214. The first 稜鏡 212 bears against the second 稜鏡 214, and the polarization splitting unit 150 is a polarizing beam splitting film, wherein the polarizing beam splitting film is located at the interface of the first 稜鏡 212 and the second 稜鏡 214, as shown in FIG. 4 .

In this embodiment, the visible light beam 112a and the invisible light beam 112b from the illumination system 110 first enter the first pupil 212, and then are polarized by the interface between the first pupil 212 and the second pupil 214. The visible light beam 112a is respectively transmitted to the visible light beam 112a having the first polarization direction P1, and the non-visible light beam 112b is, for example, the visible light beam 112b having the second polarization direction P2. Reference can be made to the first embodiment. In this embodiment, the polarizing beam splitting film can pass the light beam in the second polarization direction and can reflect the light beam in the first polarization direction as an example. However, the actual situation can also be determined according to the user's design, for example: polarization The spectroscopic film may also be a polarizing beam splitting film that passes a light beam that allows the first polarization direction to pass and that reflects the light beam in the second polarization direction.

Since the polarizing beam splitting film can pass the light beam of the second polarization direction and can reflect the light beam of the first polarization direction, the visible light beam 112a is reflected by the polarization beam splitting film and transmitted to the light valve 120, and the unvisible light beam 112b passes. The polarizing beam splitting film is transmitted to the wave plate 140 with the second germanium 214, as shown in FIG. Then, the polarization beam splitting film transmits the image beam 112c from the light valve 120 and the invisible light beam 112b from the wave plate to the object side, wherein the image beam 112c and the invisible beam 112b share the same between the polarization beam splitting film and the object side. The delivery path is shown in Figure 4.

In other words, the projection device 200 is only a method in which a polarizing beam splitting film is used in combination with a crucible to replace the grating polarizing beam splitter used in the projection device 100, and the optical principles utilized are the same as those used in the projection device 100. Therefore, the projection apparatus 200 similarly has the advantages mentioned by the above-described projection apparatus 100, and will not be described again here.

Third embodiment

FIG. 5 is a schematic structural view of a projection apparatus according to a third embodiment of the present invention. Referring to FIG. 5, the projection device 300 of the present embodiment is similar to the projection device 100 of the previous embodiment, and the same components are denoted by the same reference numerals, except that the projection device 300 does not use the partial penetration used by the projection device 100. The partial reflector 170, and the photodetector 180 is disposed only on the transmission path of the object beam 112d reflected by the object 60. In other words, if the illumination system 110, the light valve 120, the polarization splitting unit 150, the wave plate 140, the reflective element 130, and the lens 160 are regarded as an optical engine, the photodetector 180 can be disposed outside the optical engine to detect The position of the object 60 is measured.

In the present embodiment, since the image beam 112c and the invisible beam 112b share the same transmission path between the polarization beam splitting unit 150 and the object side, the light intensity distribution of the invisible light beam 112b projected onto the screen 70 can be compared. Evenly.

In summary, in the projection apparatus of the embodiment of the present invention, first, a visible light beam and an invisible light beam having different polarization directions are provided by an illumination system, wherein the illumination system utilizes a beam splitter to make the visible light beam and the invisible light beam At the same time, the same transmission path is shared to the polarization beam splitting unit, and the polarization splitting unit, the light valve, the wave plate and the reflection element are used for combining and splitting, so that the image beam and the invisible beam can share the transmission between the polarization beam splitting unit and the object side. The path, in turn, increases the space utilization of the components in the projection device, so that the volume of the projection device can be effectively reduced.

In addition, since the invisible beam and the image beam are transmitted to the object side following the same transmission path, and are also refracted by the projection lens, the invisible beam can be uniformly illuminated on the screen. Furthermore, the object beam and the invisible beam are opposite in direction of transmission between the partially penetrating partial reflector and the object side, and the transmission path is overlapped, and the object beam and the invisible beam are also refracted by the imaging lens, so the screen is in the light. The brightness on the detector is uniform, so the projection device only needs to use a gain value to detect the object beam by a single photodetector. In this way, the projection measuring device can further have a smaller volume and have better projection and image quality.

Furthermore, in the projection apparatus of the embodiment of the present invention, since the visible light beam and the invisible light beam do not simultaneously pass through the light valve, but are respectively transmitted to the object side by the action of the light valve and the reflective element, the illumination is performed. The system does not have to alternate between visible and invisible beams. In this way, the illumination system can increase the time of the visible light beam and the invisible light beam at any time interval, so that the brightness of the image projected by the projection device can be improved, and the intensity of the invisible light beam can be improved. When the intensity of the invisible beam is increased, the photodetector will also have better effects in image capturing and sensing.

While the invention has been described above in terms of a plurality of embodiments, which are not intended to limit the scope of the invention, the invention may be modified and modified without departing from the spirit and scope of the invention. Therefore, the scope of the invention is defined by the scope of the appended claims. In addition, any of the objects or advantages or features of the present invention are not required to be achieved by any embodiment or application of the invention. In addition, the abstract sections and headings are only used to assist in the search of patent documents and are not intended to limit the scope of the invention.

60. . . object

70. . . screen

100, 200, 300. . . Projection device

110. . . Lighting system

112. . . Illumination beam

112a. . . Visible beam

112b. . . Invisible beam

112c. . . Image beam

112d. . . Object beam

114. . . Visible light source

116. . . Invisible light source

118. . . Light homogenizing element

119. . . Beam splitter

120. . . Light valve

130. . . Reflective element

140. . . Wave plate

150. . . Polarization beam splitting unit

160. . . Projection lens

170. . . Partially penetrating partial reflector

180. . . Light detector

190. . . Imaging lens

192. . . control unit

212. . . First

214. . . Second

P1. . . First polarization direction

P2. . . Second polarization direction

1 is a schematic structural view of a projection apparatus according to a first embodiment of the present invention.

2A is a schematic diagram of the illumination system illustrated in FIG. 1.

2B is a diagram showing the turn-on time distribution of the visible light source and the invisible light source in FIG. 2A in one cycle time.

Fig. 3 is a view showing the configuration of a projection apparatus of a variation of the first embodiment of the present invention.

4 is a schematic structural view of a projection apparatus according to a second embodiment of the present invention.

FIG. 5 is a schematic structural view of a projection apparatus according to a third embodiment of the present invention.

60. . . object

70. . . screen

100. . . Projection device

110. . . Lighting system

112. . . Illumination beam

112a. . . Visible beam

112b. . . Invisible beam

112c. . . Image beam

112d. . . Object beam

120. . . Light valve

130. . . Reflective element

140. . . Wave plate

150. . . Polarization beam splitting unit

160. . . Projection lens

170. . . Partially penetrating partial reflector

180. . . Light detector

190. . . Imaging lens

P1. . . First polarization direction

P2. . . Second polarization direction

Claims (18)

A projection apparatus comprising: an illumination system adapted to provide an illumination beam, wherein the illumination beam comprises a visible beam and an invisible beam, the visible beam having a first polarization direction and the invisible beam having a second Polarization direction; a light valve disposed on the transmission path of the visible light beam and adapted to convert the visible light beam into an image light beam, wherein the image light beam has the second polarization direction; a reflective element disposed in the invisible light beam a transmission path adapted to reflect the invisible light beam from the illumination system; a wave plate disposed on the transmission path of the invisible light beam and located between the illumination system and the reflective element, wherein the illumination system is The invisible light beam passes through the wave plate, is reflected by the reflective element, and passes through the wave plate, wherein the invisible light beam reflected by the reflective element and passing through the wave plate has the first polarization direction; a polarization beam splitting unit disposed on the illumination beam, the image beam, and a transmission path of the invisible light beam from the wave plate, wherein The polarizing beam splitting unit transmits the visible light beam from the illumination system and the invisible light beam to the light valve and the wave plate, respectively, and causes the image beam from the light valve and the invisible light beam from the wave plate Pass to the side of the object. The projection device of claim 1, wherein the visible light beam having the first polarization direction is reflected by the polarization beam splitting unit and transmitted to the light valve, and the invisible light beam having the second polarization direction is Passing through the polarization beam splitting unit to be transmitted to the wave plate, and the invisible light beam from the wave plate having the first polarization direction is reflected by the polarization beam splitting unit and transmitted to the object side, and the light valve is from the light valve The image beam having the second polarization direction passes through the polarization beam splitting unit and is transmitted to the object side. The projection device of claim 1, wherein the visible light beam having the first polarization direction passes through the polarization beam splitting unit and is transmitted to the light valve, and the invisible light beam having the second polarization direction is Reflected by the polarization beam splitting unit and transmitted to the wave plate, the invisible light beam from the wave plate having the first polarization direction passes through the polarization beam splitting unit and is transmitted to the object side, and the light valve is from the light valve The image beam having the second polarization direction is reflected by the polarization beam splitting unit and transmitted to the object side. The projection device of claim 1, wherein the first polarization direction is substantially perpendicular to the second polarization direction. The projection device of claim 1, wherein the wave plate is a quarter wave plate. The projection device of claim 1, wherein the polarization splitting unit is a grid-shaped polarization beam splitter. The projection device of claim 1, further comprising a first cymbal and a second cymbal, the first cymbal bears against the second cymbal, and the polarizing beam splitting unit is a polarizing beam splitting film The polarizing beam splitting film is located at an interface between the first turn and the second turn. The projection device of claim 1, further comprising a projection lens disposed on the transmission path of the image beam and the invisible beam and located between the polarization beam splitting unit and the object side. The projection device of claim 8, further comprising: a portion of the transflective reflector disposed on the transmission path of the image beam and the invisible beam, and located between the projection lens and the polarization beam splitting unit The portion of the transflective reflector is adapted to transmit the image beam and a portion of the invisible beam to the object side, and an object on the object side transmits at least the portion of the invisible beam that is transmitted to the object side Partially reflecting to form an object beam; and a photodetector, wherein the portion penetrating the partial reflector causes a portion of the object beam from the object to be transmitted to the photodetector. The projection device of claim 9, wherein the image beam from the polarizing beam splitting unit and a portion of the invisible light beam are transmitted to the object side through the partially penetrating partial reflector, and the object is from the object. A portion of the object beam is reflected by the partially transmissive partial reflector to the photodetector. The projection device of claim 9, further comprising an imaging lens disposed on a transmission path of the partial object beam from the partially penetrating partial reflector, and located at the partially penetrating partial reflector and the Between the light detectors. The projection device of claim 9, wherein the photodetector is a charge coupled component or a complementary MOS sensing component. The projection device of claim 1, wherein the invisible light beam is an infrared light beam. The projection device of claim 1, wherein the illumination system comprises: at least one visible light source adapted to provide the visible light beam; an invisible light source adapted to provide the invisible light beam; and a light homogenizing element And disposed on the transmission path of the visible beam and the invisible beam, wherein the visible beam and the invisible beam are transmitted to the polarization beam splitting unit through the light homogenizing element. The projection device of claim 14, further comprising a dichroic mirror disposed on the transmission path of the visible light beam and the invisible light beam, wherein the dichroic mirror is adapted to enable the light from the invisible light source An invisible beam and the visible beam from the visible light source are delivered to the light homogenizing element. The projection device of claim 14, further comprising a control unit, wherein the at least one visible light source is a plurality of visible light sources having different illumination colors, and the control unit is electrically connected to the invisible light source and the visible light a light source to drive the visible light sources to be sequentially extinguished, and to drive the invisible light source to continuously provide the invisible light beam. The projection device of claim 14, wherein the light uniform element is a light integration column or a lens array. The projection device of claim 14, wherein the visible light source and the invisible light source are each a laser diode.