JP2008070694A - Projection system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection system capable of restraining influence by an object arranged in front of a display surface to image display. <P>SOLUTION: The projection system has a projection engine part 20 which projects light in accordance with an image signal, and a housing 11 in which the projection engine part 20 is housed. The housing 11 is attached to the periphery of a screen 12 equipped with the display surface S on which light from the projection engine part 20 is made incident, and the projection engine part 20 makes the light made incident on the display surface S advance along the display surface S. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a projection system, and more particularly to a technology of a projection system used for presentations and the like.

  Conventionally, projectors are widely used not only for viewing images but also for other purposes such as presentations. The projector is desired to be able to display an image effectively at an installation position according to the purpose. For example, Patent Document 1 proposes a technique for performing effective image display with simple settings even when the installation position of the projector is changed.

JP 2006-121231 A

  Many of the front projection projectors that have been widely used in the past are installed at a position away from the screen or the like to some extent in order to secure a projection distance. In order not to make a shadow on the image displayed on the screen or the like, it is necessary to consider that an obstacle does not enter the optical path from the projector to the screen. For example, when a presentation is performed using a front projection type projector, the presenter needs to stand at a position that does not block the projection light. As the position where the projection light is supplied is further away from the screen, there are more restrictions on the presenter's standing position. If there are many scenes in which part of the image is missing due to the shadow of the presenter, the effect of the presentation may be halved. In such a case, it is difficult for the technique of Patent Document 1 to reduce the influence on the image display exerted by placing an object in front of the display surface. The present invention has been made in view of the above, and an object of the present invention is to provide a projection system capable of reducing the influence on image display exerted by an object placed in front of a display surface. .

  In order to solve the above-described problems and achieve the object, according to the present invention, the projector includes a projection engine unit that projects light according to an image signal, and a housing that houses the projection engine unit. Is provided in the vicinity of the display surface on which light from the projection engine unit is incident, and the projection engine unit provides light that is incident on the display surface in a direction along the display surface. be able to.

  To advance the light in the direction along the display surface means to increase the angle formed by the normal line of the display surface and the light beam and to advance the light laid along the display surface. Since the light incident on the display surface is advanced in the direction along the display surface, the light can be projected from a position on the extension of the display surface and close to the display surface. The housing can be attached to a wall surface provided with a screen or the like having a display surface. Since light travels in the direction along the display surface from the extension of the display surface, even if an object is placed in front of the display surface, light from the projection engine unit is blocked unless a certain space near the display surface is blocked. There is nothing. Therefore, for example, the presenter can determine the standing position with a high degree of freedom in front of the display surface, and the frequency at which a part of the image is missing due to the shadow of the presenter can be greatly reduced. Thereby, it is possible to obtain a projection system capable of reducing the influence on the image display due to the thing placed in front of the display surface.

  Moreover, as a preferable aspect of the present invention, it is desirable to have an attachment portion for attaching the housing around the display surface. By providing the attachment portion, it is possible to make it possible to easily attach and remove the housing around the display surface.

  As a preferred aspect of the present invention, it is desirable that the projection engine unit allows light to travel in a region having a width substantially the same as the width of the housing and the mounting unit in the direction of the normal line of the display surface. Thereby, in the structure which attached the housing | casing to the periphery of the display surface, light can be incident on a display surface.

  Further, as a preferred aspect of the present invention, the casing can be attached to either the left side or the right side of the display surface, and the projection engine unit has a position where the casing is attached toward the display surface. It is desirable to flip the image upside down depending on whether it is the left side or the right side. By enabling the image to be turned upside down, an image corresponding to an image signal can be displayed regardless of whether the housing is placed on the left side or the right side of the display surface. Accordingly, an image can be displayed by appropriately attaching a housing to either the left side or the right side of the display surface according to the purpose.

  Moreover, as a preferable aspect of the present invention, it is desirable to have a correction unit that corrects an image by adjusting light from the projection engine unit. Thereby, an accurate image can be displayed regardless of the installation state of the housing.

  As a preferred aspect of the present invention, it is desirable that the correction unit includes a drive mechanism for performing at least one of movement and rotation of the projection engine unit. Thereby, the light from the projection engine unit can be adjusted.

  Moreover, as a preferable aspect of the present invention, it is desirable to have a screen having a display surface. Thereby, an image can be displayed by a projection system including a screen and a housing provided around the screen.

  As a preferred aspect of the present invention, it is desirable that the screen has an angle conversion unit that converts the angle of light from the projection engine unit. Thereby, it is possible to adjust the light from the projection engine unit to efficiently travel toward the observer.

  Moreover, as a preferable aspect of the present invention, it is desirable to provide an antireflection part that is provided between the angle conversion parts and reduces reflection of light. Thereby, reflection of external light can be reduced and a high-contrast image can be obtained. Since the light from the projection engine unit travels in the direction along the display surface, a wide area for providing the antireflection unit can be secured.

  As a preferred aspect of the present invention, the projection engine unit includes a projection lens, a first mirror that turns back the light from the projection lens by reflection, a second mirror that widens the light from the first mirror by reflection, It is desirable to provide. Thereby, light can be accurately advanced in the direction along the display surface.

  As a preferred aspect of the present invention, it is desirable that the projection engine unit includes a spatial light modulation device that modulates light according to an image signal. Thereby, the light according to an image signal can be projected.

  As a preferred aspect of the present invention, it is desirable that the projection engine unit includes a scanning unit that scans light according to an image signal in a two-dimensional direction. Thereby, the light according to an image signal can be advanced in the direction along a display surface, and an image can be displayed.

  Moreover, as a preferable aspect of the present invention, it is desirable to have a shielding portion that covers a space in which light that enters the display surface from the housing travels. By covering the space where the light before diffusion proceeds with the shielding portion, it is possible to prevent a situation such as a face entering a portion where the light intensity is concentrated.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

  FIG. 1 shows a front configuration of a projection system 10 according to a first embodiment of the present invention. FIG. 2 shows a top configuration of the projection system 10. The projection system 10 is used for presentation by the presenter P. The projection system 10 includes a housing 11 and a screen 12. The casing 11 houses a projection engine unit described later. The screen 12 includes a display surface S on which light from the projection engine unit is incident. As shown in FIG. 1, the casing 11 is attached to the left side toward the display surface S around the screen 12. The position of the casing 11 in the vertical direction substantially coincides with the central portion of the screen 12 in the vertical direction.

  As shown in FIG. 2, the casing 11 and the screen 12 are provided on a common wall surface W. The housing 11 is attached to the wall surface W by the attachment portion 13. The attachment unit 13 attaches the housing 11 to the periphery of the screen 12 in the wall surface W. For example, the attachment unit 13 includes a wall surface side member fixed to the wall surface W and a housing side member fixed to the housing 11. When using this attachment part 13, the housing | casing 11 can be attached to the predetermined position of the wall surface W by fitting a housing | casing side member to a wall surface side member. By using the attachment portion 13, it is possible to make it possible to easily attach and remove the housing 11 around the display surface S. The display surface S and the wall surface W of the screen 12 are substantially parallel. The light emitted from the housing 11 travels in the right direction where the screen 12 is disposed with respect to the housing 11. Note that the housing 11 may be attached to the screen 12 itself by the attaching portion 13. In this case, a part of the screen 12 becomes the display surface S. The entire surface of the screen 12 may not be the display surface S, and a part of the screen 12 may be the display surface S in this way.

  FIG. 3 shows a cross-sectional configuration of the projection system 10. The cross section shown in FIG. 3 is a surface along the horizontal direction and substantially orthogonal to the wall surface W. The projection engine unit 20 projects light according to the image signal. The projection engine unit 20 is housed in the housing 11. The projection engine unit 20 includes an optical engine 21, a projection lens 22, a first mirror 23, and a second mirror 24.

  FIG. 4 shows a schematic configuration of the optical engine 21. The red (R) light LED 31 </ b> R that is a solid light source is a light source unit that supplies R light. The R light from the R light LED 31R is collimated by the collimator lens 32 and then enters the R light spatial light modulator 33R. The spatial light modulator 33R for R light is a transmissive liquid crystal display device that modulates R light according to an image signal. The R light modulated by the R light spatial light modulator 33R is incident on a cross dichroic prism 34 which is a color synthesis optical system.

  The green (G) light LED 31G, which is a solid light source, is a light source unit that supplies G light. The G light from the G light LED 31G is collimated by the collimator lens 32 and then enters the G light spatial light modulator 33G. The spatial light modulator 33G for G light is a transmissive liquid crystal display device that modulates G light according to an image signal. The G light modulated by the G light spatial light modulator 33G enters the cross dichroic prism 34 from a side different from the R light.

  The blue (B) light LED 31 </ b> B that is a solid light source is a light source unit that supplies B light. The B light from the B light LED 31B is collimated by the collimator lens 32 and then enters the B light spatial light modulator 33B. The B light spatial light modulation device 33B is a transmissive liquid crystal display device that modulates B light according to an image signal. The B light modulated by the B light spatial light modulator 33B enters the cross dichroic prism 34 from a side different from the R light and the G light. The optical engine 21 may use a homogenizing optical system that uniformizes the intensity distribution of the light beam, such as a rod integrator or a fly-eye lens.

  The cross dichroic prism 34 has two dichroic films 35 and 36 arranged so as to be substantially orthogonal to each other. The first dichroic film 35 reflects R light and transmits G light and B light. The second dichroic film 36 reflects B light and transmits R light and G light. The cross dichroic prism 34 combines the R light, G light, and B light incident from different sides and emits the light toward the projection lens 22. The projection lens 22 projects the light synthesized by the cross dichroic prism 34.

  As the transmissive liquid crystal display device, for example, a high temperature polysilicon TFT liquid crystal panel (HTPS) can be used. The optical engine 21 is not limited to the case where a transmissive liquid crystal display device is used as the spatial light modulator. As the spatial light modulator, a reflective liquid crystal display (Liquid Crystal On Silicon; LCOS), DMD (Digital Micromirror Device), GLV (Grating Light Valve), or the like may be used. Further, the present invention is not limited to the case where the spatial light modulation device provided for each color light is used, and may be configured to perform modulation by a color sequential method that sequentially supplies each color light to the common spatial light modulation device. The optical engine 21 is not limited to the case where an LED is used as the light source unit. As the light source unit, for example, a solid light source other than the LED, or a lamp such as an ultrahigh pressure mercury lamp may be used.

  Returning to FIG. 3, the first mirror 23 is provided at a position facing the projection lens 22 and the second mirror 24. The first mirror 23 folds the light from the projection lens 22 in the direction of the second mirror 24 by reflection. The first mirror 23 has a substantially flat planar shape. The first mirror 23 can be configured by forming a reflective film on a parallel plate. As the reflective film, a highly reflective member layer, for example, a metal member layer such as aluminum, a dielectric multilayer film, or the like can be used. Further, a protective film having a transparent member may be formed on the reflective film.

  The second mirror 24 is a position facing the first mirror 23, and is formed on the surface on the opposite side of the inner surface of the housing 11 from the wall surface W side. The second mirror 24 widens the light from the first mirror 23 mainly in the vertical direction by reflection. Further, the second mirror 24 bends the light from the first mirror 23 and advances it in the direction of the emitting portion 25. The second mirror 24 has an aspheric curved surface. The second mirror 24 can be configured, for example, by forming a reflective film on a substrate having a resin member or the like. By making the second mirror 24 into a curved surface shape, it is possible to simultaneously perform bending and widening of light. By widening the light with the second mirror 24 as well as the projection lens 22, the projection lens 22 can be made smaller than when the light is widened only with the projection lens 22. The shape of the second mirror 24 may be appropriately changed so that the distortion of the image can be corrected.

  An emission unit 25 is provided on the surface of the housing 11 on the screen 12 side. The emitting unit 25 emits light from the projection engine unit 20 in the direction of the screen 12. The emission unit 25 includes an opening provided in the housing 11. The emission part 25 is good also as covering opening with a transparent member. The projection engine unit 20 is not limited to being completely housed in the housing 11. A part of the projection engine unit 20, for example, the second mirror 24 may be disposed so as to protrude from the emission unit 25 to the outside of the housing 11.

  The projection engine unit 20 emits light in the right direction (see FIG. 2) on the side where the screen 12 is provided when viewed from the emission unit 25. Thereby, the light from the projection engine unit 20 is allowed to enter the screen 12 efficiently by causing the light to travel directly from the projection engine unit 20 toward the screen 12.

  The projection engine unit 20 advances light in a region having a width substantially the same as the width d of the housing 11 and the mounting unit 13 in the direction of the normal line N of the display surface S. Thereby, light can be incident on the display surface S in the configuration in which the housing 11 is arranged around the screen 12. The projection engine unit 20 advances light incident on the display surface S in a direction along the display surface S. To advance the light in the direction along the display surface S means to increase the angle formed between the normal line N of the display surface S and the light beam and to advance the light laid along the display surface S. Specifically, “promotes light laid along the display surface S” means that the angle α formed between the light ray L0 incident on the center of the display surface S and the normal N of the display surface S is 45 degrees or more. Desirably, it is less than 90 degrees.

  By advancing the light from the projection engine unit 20 in the direction along the display surface S, even if the presenter P enters the front of the screen 12 as shown in FIG. 2, the projection is performed as long as a certain space near the display surface S is not obstructed. The light from the engine unit 20 is not obstructed. Therefore, the presenter P can determine the standing position with a high degree of freedom in front of the screen 12, and the frequency at which part of the image is missing due to the shadow of the presenter P can be greatly reduced. The restriction on the standing position of the presenter P is further reduced as the distance from the projection engine unit 20 increases. Therefore, it is desirable that the presenting position of the presenter P is mainly on the right side of the center of the screen 12. However, the standing position of the presenter P may be any position as long as the light from the projection engine unit 20 is not blocked.

  FIG. 5 illustrates the optical system of the projection system 10. In FIG. 5, in order to represent the optical axis AX as a straight line, illustration of the light bending in the first mirror 23 is omitted. The optical engine 21, the projection lens 22, the second mirror 24, and the screen 12 all constitute a so-called coaxial optical system having a common optical axis AX. Further, the optical engine 21, the projection lens 22, the second mirror 24, and the screen 12 constitute a so-called shift optical system in which the light from the optical engine 21 is shifted from the optical axis AX to travel to a specific side. With this configuration, light travels in the direction along the display surface S from the second mirror 24 on the screen 12.

  By employing a coaxial optical system, it is possible to adopt a normal coaxial system design method. Therefore, it is possible to realize an optical system with a small number of man-hours for designing the optical system and with few aberrations. The second mirror 24 can have a shape that is substantially rotationally symmetric with respect to the optical axis AX, for example, a shape obtained by cutting out a portion other than the apex portion of the conical shape. By making the second mirror 24 into a shape that is substantially rotationally symmetric with respect to the optical axis AX, the optical axis of the second mirror 24 and the optical axis of another configuration can be easily matched. Since the second mirror 24 has an asymmetrical aspherical shape, it can be processed by a simple method such as a lathe. Therefore, the second mirror 24 can be manufactured easily and with high accuracy.

  The projection system 10 employs an ultra-wide-angle optical system that uses the projection lens 22 and the second mirror 24 so that the angle of view θ is at least 150 degrees, for example, 160 degrees. Furthermore, by using a shift optical system that uses only a part of the range of angles that has been made super wide, it is possible to align the traveling direction of light. Assuming that the angle formed by the normal line N of the display surface S and the incident light beam is the incident angle, the light having the minimum incident angle α1 on the screen 12 is incident on the display surface S closest to the optical axis AX. The light having the maximum incident angle α2 on the screen 12 is incident on the display surface S at a position farthest from the optical axis AX. In this embodiment, for example, the minimum incident angle α1 on the display surface S is 70 degrees and the maximum incident angle α2 is 80 degrees. By adopting the shift optical system, the angle difference of the light incident on the display surface S can be within about 10 degrees.

  The projection system 10 can display an image both in the case of FIG. 1 in which the housing 11 is disposed on the left side of the screen 12 and in the case of FIG. 6 in which the housing 11 is disposed on the right side of the screen 12. The housing 11 can be attached to either the left side or the right side toward the display surface S by the attachment portion 13. Also in the case illustrated in FIG. 6, the position of the casing 11 in the vertical direction substantially coincides with the central portion of the screen 12 in the vertical direction, as in the case illustrated in FIG. 1.

  The light emitted from the housing 11 travels leftward with respect to the housing 11 where the screen 12 is disposed. The projection engine unit 20 flips the image upside down depending on whether the position where the housing 11 is attached is the left side or the right side toward the display surface S. The image can be inverted upside down by, for example, reading the video data in the reverse order. By enabling the image to be turned upside down, an image corresponding to the image signal can be displayed regardless of whether the housing 11 is placed on the left side or the right side of the display surface S. Accordingly, the image can be displayed by appropriately attaching the housing 11 to either the left side or the right side of the display surface S according to the purpose.

  The setting as to whether the position of the casing 11 is the left side or the right side of the display surface S can be switched by, for example, operating a switch or a remote controller provided in the casing 11. As described above, the setting can be switched manually, or the setting can be switched automatically by detecting the orientation of the housing 11. As a configuration for detecting the orientation of the housing 11, for example, a gravity sensor or the like can be used.

  FIG. 7 shows a cross-sectional configuration of the main part of the screen 12. The screen 12 includes a substrate 41 and a Fresnel lens 42. The substrate 41 is a parallel plate. The Fresnel lens 42 is an angle conversion unit that converts the angle of light from the projection engine unit 20 (see FIG. 3), and is provided on the display surface S side of the screen 12. Note that the substrate 12 may be omitted from the screen 12.

  The Fresnel lens 42 has a plurality of prism portions 43. The prism portion 43 has a triangular cross-sectional configuration. A reflecting portion 45 is provided on the surface of the prism portion 43. The reflection unit 45 reflects the projection light L1 from the projection engine unit 20 in the direction of the observer. As the reflecting portion 45, for example, a metal film having minute irregularities can be used. By using a metal film having minute irregularities, the reflection unit 45 reflects and diffuses the projection light L1. By reflecting and diffusing the projection light L1 toward the viewer, it is possible to display a bright image with good viewing angle characteristics. By forming the reflection portions 45 on the two surfaces of the prism portion 43, the projection light L1 is reflected in the direction of the observer regardless of whether the projection light L1 enters from the left side of the screen 12 or the right side. Can be made.

  Since the traveling direction of the projection light L1 incident on the screen 12 can be made uniform, the prism portions 43 can be configured to have surfaces with substantially the same inclination. By making it possible to form the prism portion 43 having substantially the same inclined surfaces, the processing of the Fresnel lens 42 can be facilitated. Thereby, the manufacturing cost of the screen 12 can be reduced. By aligning the traveling direction of the projection light L1 incident on the screen 12, the luminance distribution can be made uniform. In addition, since the projection light L1 traveling in the direction along the screen 12 is reflected by the prism portion 43, it is possible to provide an interval between the prism portions 43.

  An antireflection part 44 is provided between the prism parts 43. The antireflection unit 44 reduces light reflection. The antireflection part 44 can be configured by applying a light absorbing member, for example. By absorbing the external light L2 with the antireflection part 44 formed of a light absorbing member, the reflection of the external light L2 can be reduced. As the light absorbing member, for example, a resin member containing a coloring material can be used. Moreover, you may use the absorber which absorbs the light of a specific wavelength range as a light absorbing member. By providing the antireflection part 44, reflection of the external light L2 can be reduced and a high-contrast image can be obtained. Since the projection light L1 travels in the direction along the screen 12, a wide area for providing the antireflection portion 44 can be secured.

  FIG. 8 shows a planar configuration of the Fresnel lens 42. The prism portion 43 has a longitudinal direction in the vertical direction and is arranged in parallel in the horizontal direction with the antireflection portion 44 interposed therebetween. Thereby, even if the housing | casing 11 is attached to any of the left side of the screen 12, and the right side, the light from the projection engine part 20 can be advanced to an observer's direction. The Fresnel lens 42 is not limited to a configuration in which prism portions 43 having a longitudinal direction in the vertical direction are arranged in parallel in the horizontal direction. For example, the Fresnel lens 42 may have a structure in which prismatic prism portions having a quadrangular pyramid shape are arranged in parallel in a two-dimensional direction. The prism portions may be arranged concentrically in addition to being arranged in parallel in the horizontal direction. If a sufficiently bright image can be displayed, a general-purpose screen that does not have an angle conversion unit may be used.

  Since the projection system 10 advances light in the direction along the display surface S from the extension of the display surface S, even if an object is placed in front of the display surface S, it does not obstruct a certain space near the display surface S. The light from the projection engine unit 20 is not hindered. Therefore, the presenter P (see FIG. 2) can determine the standing position with a high degree of freedom in front of the display surface S, and the frequency at which a part of the image is missing due to the shadow of the presenter P can be greatly reduced. Thereby, there exists an effect that the influence on the image display by the thing being arranged in front of the display surface S can be reduced. The projection system 10 is useful when used for presentation in a classroom or a conference room, for example. In addition, the projection system 10 may be used for image viewing or the like. When the projection system 10 is used, since the influence on the image display by the observer in front of the screen 12 can be reduced, comfortable image viewing can be performed.

  In order to prevent projection light from being interrupted by an observer or the like, a conventional projector may be installed at a position higher than the observer as a ceiling suspension or the like. Compared with the case of using a ceiling-suspended projector, the projector system 10 according to the present invention has advantages such as that it is possible to reduce the installation effort, facilitate the arrangement of the cord, and facilitate maintenance such as lamp replacement. . Further, the projection system 10 of the present invention is easier to attach and detach the housing 11 than in the case of a fixed type such as a conventional ceiling-suspended type. Therefore, a safe storage place every time the projection system 10 is used. It is possible to store the housing 11 in the housing. By making the housing 11 storable, effects such as theft prevention and tampering prevention can also be achieved. Note that the projection system 10 is not limited to the configuration including the specific screen 12. The projection system 10 may display an image by combining an arbitrary display surface and the housing 11.

  The projection system 10 is not limited to the case where the housing 11 can be attached to either the left side or the right side of the screen 12. For example, the housing 11 may be attached only to a specific position around the screen 12. In this case, the position where the housing 11 is attached is not limited to the left side or the right side of the screen 12, and may be the upper side or the lower side of the screen 12.

  FIG. 9 shows a configuration of a projection system 50 according to the second embodiment of the present invention. The projection system 50 according to the present embodiment includes a drive mechanism 52 that is a correction unit. The same parts as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted. The projection engine unit 20 is stored in a projection engine storage unit 51 in the housing 11. The drive mechanism 52 is provided between the housing 11 and the projection engine storage unit 51.

  The drive mechanism 52 adjusts the light from the projection engine unit 20 by moving and rotating the projection engine unit 20 together with the projection engine storage unit 51. The projection system 50 can optimize the position and inclination of the projection engine unit 20 by measuring the distance between the display surface S and the end surface of the housing 11 and the direction and inclination of the housing 11 and inputting them to the operation unit, for example. This is done automatically by the drive mechanism 52. In addition, the position and inclination of the projection engine unit 20 may be directly adjustable by a user operation. The drive mechanism 52 corrects the image by adjusting the light from the projection engine unit 20. Thereby, an accurate image can be displayed regardless of the installation state of the housing 11.

  The drive mechanism 52 is not limited to one that moves and rotates the projection engine unit 20, and may be any mechanism that performs at least one of movement and rotation of the projection engine unit 20. The correction unit may use not only the driving mechanism 52 that moves and rotates the projection engine unit 20 but also a mechanism for adjusting elements of the projection engine unit 20, for example, the position and inclination of the second mirror 24. Furthermore, when the correction of the image is insufficient only by the adjustment using the adjustment mechanism, the correction unit may correct the image by appropriately converting the image signal.

  FIG. 10 shows a configuration of a projection system 60 according to the third embodiment of the present invention. The projection system 60 of this embodiment includes a first scanning unit 65 and a second scanning unit 66 that are scanning units. The same parts as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted. The projection engine 67 includes an R light laser 61R, a G light laser 61G, and a B light laser 61B. The R light laser 61R is a light source unit that supplies R light that is laser light. The G light laser 61G is a light source unit that supplies G light, which is laser light. The B light laser 61B is a light source unit that supplies B light, which is laser light. Each of the color light lasers 61R, 61G, and 61B supplies laser light modulated in accordance with an image signal.

  The first dichroic mirror 62 transmits R light and reflects G light. The second dichroic mirror 63 transmits R light and G light and reflects B light. The R light from the R light laser 61 </ b> R passes through the first dichroic mirror 62 and the second dichroic mirror 63 and then enters the first scanning unit 65. The G light from the G light laser 61 </ b> G is incident on the first dichroic mirror 62 after the optical path is bent by the reflection mirror 64. The G light incident on the first dichroic mirror 62 is reflected by the first dichroic mirror 62 and then enters the second dichroic mirror 63. The G light incident on the second dichroic mirror 63 passes through the second dichroic mirror 63 and then enters the first scanning unit 65. The B light from the B light laser 61 </ b> B is reflected by the second dichroic mirror 63 and then enters the first scanning unit 65. The configuration for causing the laser beams from the lasers 61R, 61G, and 61B to enter the first scanning unit 65 is not limited to that of the present embodiment, and may be changed as appropriate.

  The first scanning unit 65 scans each color light in the horizontal direction. The second scanning unit 66 scans each color light from the first scanning unit 65 in the vertical direction. The first scanning unit 65 and the second scanning unit 66 are scanning units that scan light according to an image signal in a two-dimensional direction. As the 1st scanning part 65 and the 2nd scanning part 66, the mirror formed so that rotation was possible, for example, a MEMS mirror, a galvanometer mirror, etc. can be used. Further, one of the first scanning unit 65 and the second scanning unit 66 may be a polygon mirror. The scanning unit is not limited to the configuration including the first scanning unit 65 and the second scanning unit 66, and may be configured to scan each color light in a two-dimensional direction using a single mirror or the like.

  The projection system 60 can achieve a small size, high resolution, and high light utilization efficiency by adopting a configuration in which laser light is scanned by a scanning unit. As in the first embodiment, the laser intensity can be effectively dispersed by diffusing light with the Fresnel lens 42 (see FIG. 7). Also in the case of the present embodiment, as in the case of the first embodiment, it is possible to reduce the influence on the image display due to the object being arranged in front of the display surface S. In addition, when using a scanning part, there exists an advantage that the area | region to which the light according to an image signal is scanned can be changed easily. For this reason, the housing 11 may be disposed at any position around the screen 12, for example, at a position near the corner of the screen 12.

  FIG. 11 shows a configuration of a projection system 70 according to Embodiment 4 of the present invention. The projection system 70 includes a shielding part 71. The same parts as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted. The shielding unit 71 covers a space in which light that enters the display surface S of the screen 12 from the housing 11 travels. The shielding part 71 is a parallel plate and is arranged obliquely along the optical path of the light from the emitting part 25.

  The light passing between the housing 11 and the screen 12 is light before entering the display surface S, and is in a state before being sufficiently diffused. By covering the space where the light before diffusion travels with the shielding portion 71, it is possible to prevent a situation such as a face entering the space where the light intensity is concentrated. In the conventional configuration in which the projector is installed at a position away from the screen, it is extremely difficult to shield the space in which light travels before entering the display surface. On the other hand, if it is the structure which advances the light from the projection engine part 20 in the direction along the display surface S, the space where the light before entering into the screen 12 advances can be shielded easily.

  The shielding part 71 is only required to be able to prevent entry into a space where the intensity of light is concentrated, and may be composed of either a transparent member or a non-transparent member. The shielding part 71 should just be the structure which covers the range where the intensity | strength of light concentrates on the output part 25 as a center. For this reason, the shielding part 71 can be comprised with the width | variety below the dimension of the screen 12 about the depth direction of FIG. The shielding unit 71 may be appropriately modified so as to surround a space in which light before diffusion proceeds.

  As described above, the projection system according to the present invention is particularly useful when used for presentations.

The figure which shows the front structure of the projection system which concerns on Example 1 of this invention. The figure which shows the upper surface structure of a projection system. The figure which shows the cross-sectional structure of a projection system. The figure which shows schematic structure of an optical engine. The figure explaining the optical system of a projection system. The figure explaining the aspect which arrange | positions a housing | casing on the right side of a screen. The figure which shows the principal part cross-section structure of a screen. The figure which shows the plane structure of a Fresnel lens. The figure which shows the structure of the projection system which concerns on Example 2 of this invention. The figure which shows the structure of the projection system which concerns on Example 3 of this invention. The figure which shows the structure of the projection system which concerns on Example 4 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Projection system, 11 Case, 12 Screen, S Display surface, 13 Mounting part, W Wall surface, 20 Projection engine part, 21 Optical engine, 22 Projection lens, 23 1st mirror, 24 2nd mirror, 25 Output part, N Normal, 31R R light LED, 31G G light LED, 31B B light LED, 32 collimator lens, 33R R light spatial light modulation device, 33G G light spatial light modulation device, 33B B light spatial light modulation Device, 34 Cross dichroic prism, 35 First dichroic film, 36 Second dichroic film, 41 Substrate, 42 Fresnel lens, 43 Prism unit, 44 Antireflection unit, 45 Reflection unit, 50 Projection system, 51 Projection engine storage unit, 52 Drive mechanism, 60 projection system, 61 R R laser, 61 G G laser, 61 B B laser, 62 first dichroic mirror, 63 second dichroic mirror, 64 reflecting mirror, 65 first scanning unit, 66 second scanning unit, 67 projection engine unit 70 projection system 71 shield

Claims (13)

A projection engine unit that projects light according to an image signal;
A housing that houses the projection engine unit,
The casing is attached to the periphery of a display surface on which light from the projection engine unit is incident,
The projection engine unit causes light incident on the display surface to travel in a direction along the display surface.   The projection system according to claim 1, further comprising an attachment portion for attaching the casing to the periphery of the display surface.   The projection system according to claim 2, wherein the projection engine unit causes light to travel in a region having a width substantially the same as a width of the housing and the mounting unit in a direction of a normal line of the display surface. . The housing can be attached to either the left side or the right side toward the display surface,
4. The projection engine unit according to claim 1, wherein the projection engine unit flips the image upside down depending on whether the position where the housing is attached is the left side or the right side of the display surface. The projection system according to one item.   The projection system according to claim 1, further comprising a correction unit that corrects an image by adjusting light from the projection engine unit.   The projection system according to claim 5, wherein the correction unit includes a drive mechanism for performing at least one of movement and rotation of the projection engine unit.   The projection system according to claim 1, further comprising a screen having the display surface.   The projection system according to claim 7, wherein the screen includes an angle conversion unit that converts an angle of light from the projection engine unit.   The projection system according to claim 8, further comprising an antireflection portion that is provided between the angle conversion portions and reduces reflection of light.   The projection engine unit includes a projection lens, a first mirror that turns back light from the projection lens by reflection, and a second mirror that widens the light from the first mirror by reflection. The projection system as described in any one of Claims 1-9.   The projection system according to claim 1, wherein the projection engine unit includes a spatial light modulation device that modulates light according to the image signal.   The projection system according to claim 1, wherein the projection engine unit includes a scanning unit that scans light according to the image signal in a two-dimensional direction.   The projection system according to claim 1, further comprising a shielding portion that covers a space in which light incident from the housing to the display surface travels.

Images