Projection screen device and projection system
By introducing a synchronous winding structure and edge strip winding structure into the projection screen device, the stress concentration problem caused by the structural concave and convexity of the projection screen is solved, the formation of tube embossment is avoided, and the display quality and use are improved. Lifespan and space savings are achieved.
Patent Information
- Application Number
- CN202421145954.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-21
- Publication Date
- 2025-01-07
- Estimated Expiration
- 2034-05-21
AI Technical Summary
The projection screen is under the coiled state due to stress concentration due to the concave and convex structure, and periodic stripe-like indentation (tube embossing) is prone to occur after long-term use, which affects the viewing experience, especially in high requirements such as polymer materials or light-resistant curtains. The display quality is more obvious.
Design a projection screen device, by setting a synchronous winding structure between the screen and the edge strip, using the edge strip winding structure to rotate and space adjacent layered curtains when the screen winds, to avoid the embossment formed by extrusion. And rotate the outer edge bars simultaneously when the screen is expanded to ensure that the edge bars do not affect the appearance of the screen.
It effectively avoids the squeezing between the screen layers to form periodic tube embossing, improves the display quality and service life of the projection screen, and saves space when not in use.
Smart Images
Figure CN222319280U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of projection display technology, and in particular to a projection screen device and a projection system including the projection screen device. Background Art
[0002] The lifting projection screen can be used in homes, meeting rooms, cars, etc. When the projection screen is not in use, it will be rolled up onto the reel, thus saving space.
[0003] However, due to some structural bumps on the reel, when the projection screen is rolled up, the rolled-up multi-layer projection screen squeezes each other and produces stress concentration at uneven locations. Over a long period of time, the molecular chains in the projection screen will deform. Coupled with the influence of some other factors, there is a certain probability that the surface of the projection screen will appear as follows after a long period of rolling up: Figure 1 The periodic stripe-like indentations shown ( Figure 1 The horizontal white indentation shown, hereinafter referred to as "tube embossing"), affects the viewing experience.
[0004] The formation of tube embossing is affected by many factors, such as the properties of the projection screen material itself (elastic modulus, surface hardness, etc.), the thickness of the projection screen, the diameter of the reel, the reel reeling force, the size of the uneven part on the reel, and the time of reeling. Among them, tube embossing is more likely to appear in projection screens with polymer materials as the substrate, but it is less common in projection screens with fabric as the substrate (fabric is wrinkle-resistant). At the same time, the general white screen is close to the Lambertian body, which is less affected by the viewing angle, and the difference in the picture is not obvious when the surface is deformed. For projection screens that pursue higher display quality, such as anti-glare screens, because of the use of designs such as adding microstructures and using metal coatings, the viewing effect is greatly affected by the viewing angle, and the difference in the picture is more obvious after the surface is deformed, so it is more sensitive to tube embossing. Utility Model Content
[0005] In a first aspect, the present application provides a projection screen device, comprising: a screen having a display surface, the display surface being used to display an image when receiving projection light; a side strip having a first end and a second end, the first end being fixed to the screen; a screen rolling structure, the end of the screen to which the side strip is fixed being fixed to the screen rolling structure, the screen rolling structure being used to synchronously roll up or extend outward the screen and the side strip, when the screen and the side strip are in a rolled-up state, two adjacent layers of the screen are separated by the side strip; and a side strip rolling structure, the second end of the side strip being fixed to the side strip rolling structure, the side strip rolling structure being used to extend the side strip when the screen rolling structure rolls up the side strip, and being used to roll up the side strip when the screen rolling structure extends the side strip.
[0006] In at least one embodiment of the present application, the side strip rolling structure includes two bases and a rotating shaft rotatably connected between the two bases; the second end of the side strip is fixedly connected to the rotating shaft.
[0007] In at least one embodiment of the present application, the side strip rolling structure is a passive structure, which is used to rotate under the drive of the screen rolling structure to roll up or extend the side strip.
[0008] In at least one embodiment of the present application, the edge strip rolling structure further includes an elastic member, one end of the elastic member is fixed to one of the bases, and the other end is fixed to the rotating shaft; when the rotating shaft rotates, the elastic member stores or releases elastic potential energy.
[0009] In at least one embodiment of the present application, the side strip rolling structure is an active structure, which is used to rotate synchronously with the screen rolling structure to roll up or extend the side strip.
[0010] In at least one embodiment of the present application, the side strip rolling structure further includes a motor, one end of the motor is fixed to one of the bases, and the other end is fixed to the rotating shaft; the motor is used to drive the rotating shaft to rotate to roll up or release the side strip.
[0011] In at least one embodiment of the present application, the projection screen device includes two side strips, and the second ends of the two side strips are wound around the rotating shaft at intervals.
[0012] In at least one embodiment of the present application, the projection screen device includes two side strip rolling structures, and the two side strips are respectively wound on the rotating shafts of the two side strip rolling structures.
[0013] In at least one embodiment of the present application, the first end of the side strip is fixed to the display surface of the screen.
[0014] A second aspect of the present application provides a projection system, comprising: any one of the above-mentioned projection screen devices; and a projector, used to project projection light onto the display surface of the projection screen device so that the display surface displays a projection image.
[0015] In the above-mentioned projection screen device and projection system, in the first aspect, the projection screen device includes a screen, side strips and a screen rolling structure. Since the side strips are fixed to the screen, the screen rolling structure is used to synchronously roll up or release the screen and side strips. Therefore, when the screen is in a rolled-up state, the side strips are also in a rolled-up state, so that the screen and the side strips are staggered and rolled up; that is, each two adjacent layers of the screen are separated by the side strips; this can effectively improve the problem of periodic tube embossing formed by extrusion between the screen layers. In the second aspect, the projection screen device also includes a side strip rolling structure, and the side strip rolling structure is used to roll up or release the side strips. When the screen rolling structure rolls up the side strips, the side strip rolling structure can synchronously rotate the side strips to release the side strips, so that the side strips are rolled up in the screen rolling structure to separate the adjacent stacked curtains. When the screen rolling structure releases the side strips, the side strip rolling structure can synchronously rotate to roll up the side strips to prevent the side strips from affecting the appearance of the screen. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 The figure is a schematic diagram of the structure of the projection screen producing tube embossing state in the prior art.
[0017] Figure 2 It is a front perspective schematic diagram of a projection screen device according to an embodiment of the present application.
[0018] Figure 3 It is a side perspective schematic diagram of a projection screen device according to an embodiment of the present application.
[0019] Figure 4 for Figure 1 Schematic diagram of the structure when the middle screen and the side strips are rolled up by the screen rolling structure.
[0020] Figure 5 This is a three-dimensional structural diagram of the side strip rolling structure and the side strip according to an embodiment of the present application.
[0021] Figure 6 for Figure 5 Exploded view of the middle side strip rolling structure and side strips.
[0022] Figure 7 This is a three-dimensional structural diagram of the side strip rolling structure and the side strip of the first modified embodiment of the present application.
[0023] Figure 8 for Figure 7 Exploded view of the middle side strip rolling structure and side strips.
[0024] Fig. 9 This is a three-dimensional structural diagram of the side strip rolling structure and the side strip according to the second modified embodiment of the present application.
[0025] Fig.10 This is a three-dimensional structural diagram of the side strip rolling structure and the side strip according to the third modified embodiment of the present application.
[0026] Fig.11 for Fig.10 A local enlarged structural diagram.
[0027] Fig.12 Schematic diagram of the structure of the projection system according to an embodiment of the present application.
[0028] Main component symbols
[0029] Projection screen device 1
[0030] Housing 10
[0031] Storage space 11
[0032] Screen 20
[0033] Curtain 21, A, B
[0034] Display surface 211
[0035] Non-display surface 212
[0036] Counterweight 22
[0037] Support 23
[0038] Edge strip 30
[0039] First end 31
[0040] Second end 32
[0041] Screen rolling structure 40
[0042] Shaft 41
[0043] Motor 42
[0044] Edge strip rolling structure 50
[0045] Base 51, 52
[0046] Shaft 53
[0047] Elastic member 54
[0048] Motor 55
[0049] Synchronous parts 56
[0050] Projector 2
[0051] Projection system 100
[0052] The following specific implementation methods will further illustrate the present application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION
[0053] The embodiment of the present application provides a projection screen device and a projection system including the projection screen device. The projection screen device includes a screen, side strips, a screen rolling structure and a side strip rolling structure. The present application mainly fixes the side strips to the screen and the side strip rolling structure respectively, so that the screen rolling structure can synchronously roll up or unfold (or put out) the screen and the side strips. Therefore, when the screen rolling structure rolls up the screen and the side strips, each two adjacent layers of the screen are separated by the side strips, which is conducive to avoiding the screen parts from being squeezed to form tube embossing; when the screen rolling structure puts the screen and the side strips out, the side strip rolling structure can roll up the side strips to avoid affecting the appearance of the screen.
[0054] The projection screen device of the embodiment of the present application can be used in places such as homes, meeting rooms, and cars. When in use, the screen is unfolded to receive projection light to display images. When not in use, the screen is rolled up by the screen rolling structure, thereby saving space.
[0055] Please also read Figure 2 and Figure 3 The projection screen device 1 of this embodiment includes a housing 10, a screen 20, two side strips 30, a screen rolling structure 40 and a side strip rolling structure 50. The housing 10 is formed with a storage space 11, and the two side strips 30, the screen rolling structure 40 and the side strip rolling structure 50 are located in the storage space 11. The screen 20 is partially located in the storage space 11.
[0056] One end (referred to as the fixed end) of the screen 20 is fixed to the screen rolling structure 40, and the other end is a free end. Each side strip 30 includes a first end 31 and a second end 32 opposite to each other. The first ends 31 of the two side strips 30 are fixed to the screen 20, and the second ends 32 are fixed to the side strip rolling structure 50. The screen rolling structure 40 is used to roll up or unfold the two side strips 30 of the screen 20, and the side strip rolling structure 50 is used to roll up or unfold the two side strips 30. The screen rolling structure 40 and the side strip rolling structure 50 roll up the side strips 30 in opposite directions, and the directions of unfolding the side strips 30 are also opposite.
[0057] When the projection screen device 1 is not in use, the screen 20 is partially stored in the storage space 11. When the screen rolling structure 40 unfolds the screen 20, the screen 20 gradually extends out of the storage space 11 through an opening (not shown) on the housing 10, and the free end gradually moves away from the housing 10. When the screen rolling structure 40 rolls up the screen 20, the screen 20 is gradually partially stored in the storage space 11 through the opening (the free end remains outside the storage space 11).
[0058] The screen 20 includes a curtain 21 and a counterweight 22 fixedly connected to the curtain 21. The counterweight 22 is in the shape of a long strip and is fixed to the free end of the curtain 21. The screen 20 is in a rolled-up state (see FIG. Figure 4), the curtain 21 is located in the storage space 11, and the counterweight 22 is located outside the storage space 11. When the screen 20 is in the unfolded state (such as Figure 2 and Figure 3 In the state shown in the figure, most of the screen 21 is located outside the storage space 11, and the fixed end and the part close to the fixed end are still located in the storage space 11 and are wound on the screen rolling structure 40, which can improve the firmness of the fixing of the screen 21 and the flatness of the screen 21 after it is unfolded. The overall weight of the screen 21 is relatively light, and the counterweight 22 is used to keep the screen 21 in a relatively flat hanging state when the screen 20 is in the unfolded state, which is conducive to improving the display quality of the projected image displayed on the screen 21.
[0059] The curtain 21 has a display surface 211 and a non-display surface 212 located on the back side of the display surface 211. The display surface 211 is used to display the projected image when receiving the projection light. The screen 20 also includes a support member 23 fixedly attached to the non-display surface 212. The support member 23 is synchronously rolled up or unfolded with the curtain 21. Since the curtain 21 is a flexible structure, the support member 23 is used to support the curtain 21, which is conducive to keeping the curtain 21 flat. And the support member 23 is located on the non-display surface 212, which does not affect the image displayed by the curtain 21. The support member 23 can be strip-shaped, X-shaped, etc.
[0060] In this embodiment, the two side strips 30 have basically the same structure and function. The thickness of the two side strips 30 is 10 to 100 μm (including the end values), and the material can be a rollable material such as a polymer material, a fabric, a metal foil / tape, etc. Each side strip 30 has a first end 31 and a second end 32. In this embodiment, the first end 31 of each side strip 30 is fixedly connected to the display surface 211 of the curtain 21, and is fixedly connected to one end of the curtain 21 connected to the screen rolling structure 40. The second end 32 of each side strip 30 is wound around the side strip rolling structure 50. In other embodiments of the present application, each side strip 30 can also be fixedly connected to the non-display surface 211 of the curtain 21, and is fixedly connected to one end of the curtain 21 connected to the screen rolling structure 40.
[0061] The screen rolling structure 40 and the side strip rolling structure 50 both roll up the screen 20 and the side strip 30 in a rotating manner. Figure 4 ( Figure 4The middle arrow indicates the moving direction of the screen cloth 21 and the side strips 30 during the process of rolling up the screen cloth 21 and the side strips 30 by the screen rolling structure 40. In this embodiment, the screen 20 and the two side strips 30 are rolled up synchronously during the clockwise rotation of the screen rolling structure 40. At this time, the side strip rolling structure 50 rotates clockwise synchronously with the screen rolling structure 40 to release the two side strips 30. When the screen rolling structure 40 rotates counterclockwise, the screen 20 and the two side strips 30 are released synchronously. At this time, the side strip rolling structure 50 rotates counterclockwise synchronously with the screen rolling structure 40 to roll up the two side strips 30. That is, the screen rolling structure 40 and the side strip rolling structure 50 keep rotating synchronously in the same direction, so that the screen 20 and the two side strips 30 are synchronously rolled up and released by the screen rolling structure 40, and the two side strips 30 are rolled up by the side strip rolling structure 50 after being released by the screen rolling structure 40.
[0062] Depend on Figure 4 It can be seen that when the screen 20 and the two side strips 30 are rolled up in the screen rolling structure 40, the curtain cloth 21 and the two side strips 30 are stacked into multiple layers in the circumferential direction of the screen rolling structure 40. Moreover, there is a side strip 30 between every two adjacent layers of curtain cloth 21. That is, every two adjacent layers of curtain cloth 21 are separated by the side strip 30. For example Figure 3 The two adjacent layers of curtains A and B are separated by edge strips 30.
[0063] In this embodiment, when the screen 20 and the two side strips 30 are rolled up in the screen rolling structure 40, the two side strips 30 are in physical contact with the screen 21, and there is no colloid. Therefore, when the screen rolling structure 40 releases the screen 21 and the side strips 30, the screen 21 and the side strips 30 are naturally separated. In this embodiment of the application, by fixing the two side strips 30 on the screen 21, it is helpful to avoid the adjacent stacked screens 21 from squeezing each other to produce periodic tube embossing.
[0064] Please also read Figure 5 and Figure 6 In this embodiment, the edge strip rolling structure 50 is a passive structure, including two bases 51 and 52, a hollow rotating shaft 53 and an elastic member 54. The rotating shaft 53 is rotatably connected between the two bases 51 and 52, and one end of the elastic member 54 is fixedly connected to one of the bases 51, and the other end is fixedly connected to the rotating shaft 53 and is located inside the rotating shaft 53. When the rotating shaft 53 rotates, the elastic member 54 stores or releases elastic potential energy. In this embodiment, the elastic member 54 is a spring.
[0065] In this embodiment, when the screen rolling structure 40 rotates to roll up the curtain 21 and the side strip 30, since the side strip 30 is respectively fixedly connected to the curtain 21 and the rotating shaft 53 in the side strip rolling structure 50, the screen rolling structure 40 rotates to drive the curtain 21 to rotate, and a pulling force is synchronously applied to the side strip 30, and a pressure is further applied to the rotating shaft 53, which synchronously drives the rotating shaft 53 to rotate. At this time, the elastic member 54 in the side strip rolling structure 50 stores elastic potential energy. When the screen rolling structure 40 rotates to release the curtain 21 and the side strip 30, since the side strip 30 is respectively fixedly connected to the curtain 21 and the rotating shaft 53 in the side strip rolling structure 50, the screen rolling structure 40 rotates to drive the curtain 21 to rotate, and the curtain 21 and the side strip 30 are synchronously released. At this time, the elastic member 54 releases the elastic potential energy, and the rotating shaft 53 rotates to roll up the side strip 30 released by the screen rolling structure 40.
[0066] In this embodiment, since the side strip rolling structure 50 is a passive structure, it needs to rotate synchronously under the drive of the screen rolling structure 40, so it is necessary to keep the force of the side strip rolling structure 50 on the side strip 30 smaller than the force of the screen rolling structure 40 on the side strip. That is, when the screen rolling structure 40 drives the curtain 21 to rotate and simultaneously applies a pulling force to the side strip 30, the pulling force must be large enough to overcome the force of the elastic force of the elastic member 54 on the side strip 30, so that the screen rolling structure 40 can pull the side strip 30 out of the side strip rolling structure 50 and release the rolled state.
[0067] Please also read Figure 7 and Figure 8 In the first modified embodiment of the present application, the projection screen device 1 includes two side strip rolling structures 50 as in the above-mentioned embodiment. The two side strip rolling structures 50 are independently arranged at intervals from each other and have basically the same structure and function. Each side strip rolling structure 50 includes two bases 51 and 52, a hollow rotating shaft 53 and an elastic member 54. The two side strips 30 are respectively wound on the rotating shaft 53 of a corresponding side strip rolling structure 50. The axes of the rotating shafts 53 in the two side strip rolling structures 50 coincide.
[0068] The bases 51 and 52, the hollow shaft 53 and the elastic member 54 in the first modified embodiment are Figure 5-Figure 6 The difference is that the sum of the lengths of the two rotating shafts 53 in the first modified embodiment is less than Figure 5-Figure 6 The length of the rotating shaft 53 in. Figure 5-Figure 6 The length of the rotating shaft 53 (i.e., the dimension from the base 51 to the base 52) is greater than the width of the screen 21 (perpendicular to the rolling direction or the unfolding direction of the screen 21). In the first modified embodiment, the lengths of the two rotating shafts 53 are respectively less than the width of the screen 21. Therefore, the structure in the first modified embodiment is conducive to saving space and is suitable for projection screen devices with limited space in the housing 10.
[0069] See also Fig. 9 In the second modified embodiment of the present application, the side strip rolling structure 50 is an active structure, including two bases 51 and 52, a rotating shaft 53 and a motor 55. The rotating shaft 53 is rotatably connected between the two bases 51 and 52, and one end of the motor 55 is fixedly connected to one of the bases 51, and the other end is connected to the rotating shaft 53. The motor 55 is used to drive the rotating shaft 53 and the screen rolling structure 40 to rotate synchronously in the same direction.
[0070] In the above-mentioned embodiments, the housing 10 can be fixed to a structure such as a wall, and the screen rolling structure 40 releases the screen 21 from top to bottom.
[0071] Please also read Fig.10 and Fig.11 In the third modified embodiment of the present application, the screen rolling structure 40 extends the screen 21 from bottom to top. That is, when the projection screen device 1 is idle, the screen 21 is rolled up in the screen rolling structure 40, and when the screen rolling structure 40 extends the screen 21, the screen 21 can be gradually unfolded upward (away from the ground) with the assistance of the support member 23.
[0072] In the third modified embodiment, the side strip rolling structure 50 further includes a synchronous member 56. One end of the synchronous member 56 is fixedly connected to the screen rolling structure 40, and the other end is fixedly connected to the rotating shaft 53, so that the rotating shaft 53 can rotate synchronously with the screen rolling structure 40. In this embodiment, the synchronous member 56 is a synchronous belt. In at least one modified embodiment, the synchronous member 56 can also be a gear assembly.
[0073] In other embodiments of the present application, according to the needs of actual usage scenarios, the screen rolling structure 40 can release the screen 21 from other directions, such as from left to right or from left to right.
[0074] In any of the above embodiments, the screen rolling structure 40 is an active structure, including a rotating shaft 41 and a motor 42 for driving the rotating shaft to rotate. In the above third modified embodiment, the synchronous member 56 can be fixed on the motor 42 of the screen rolling structure 40.
[0075] In the above-mentioned embodiments of the present application, in the first aspect, the projection screen device 1 includes a screen 20, a side strip 30 and a screen rolling structure 40. Since the side strip 30 is fixed to the screen 20, the screen rolling structure 40 is used to synchronously roll up or extend the screen 20 and the side strip 30. Therefore, when the screen 20 is in a rolled-up state, the side strip 30 is also in a rolled-up state, thereby realizing staggered rolling of the screen 20 and the side strip 30; that is, each two adjacent layers of the screen 20 are separated by the side strip 30; this can effectively improve the problem of periodic tube embossing formed by extrusion between the layers of the screen 20.
[0076] In a second aspect, the projection screen device 1 further includes a side strip rolling structure 50, which is used to roll up or release the side strip 30. When the screen rolling structure 40 rolls up the side strip 30, the side strip rolling structure 50 can be rotated synchronously to release the side strip 30, so that the side strip 30 is rolled up in the screen rolling structure 40 to separate adjacent stacked curtains 21. When the screen rolling structure 40 releases the side strip 30, the side strip rolling structure 50 can be rotated synchronously to roll up the side strip 30, so that the side strip 30 is always stored inside the housing 10 (kept wound on the screen rolling structure 40 and / or the side strip rolling structure 50), which inevitably affects the appearance of the screen 20.
[0077] See also Fig.12 The projection system 100 of the embodiment of the present application includes the projection screen device 1 and the projector 2 in any of the above embodiments. The projector 2 is located on the side of the display surface 211 of the screen 21, and is used to emit projection light toward the display surface 211. The display surface 211 of the screen 21 displays the projection image when receiving the projection light. In this embodiment, the area of the display region P of the projection image is smaller than the area of the display surface 211, so as to facilitate the complete display of the projection image.
[0078] The projection system 100 of the embodiment of the present application can achieve the beneficial effects of the projection screen device 1 in any of the above embodiments, which will not be described in detail.
[0079] Those skilled in the art should recognize that the above implementation modes are only used to illustrate the present application, and are not used as limitations on the present application. As long as they are within the spirit and scope of the present application, appropriate changes and modifications to the above embodiments are within the scope of protection claimed in the present application.
Claims
1. A projection screen device, characterized in that: include: a screen having a display surface for displaying an image when receiving projection light; A side strip having a first end and a second end, wherein the first end is fixed to the screen; A screen rolling structure, wherein one end of the screen to which the side strip is fixed is fixed to the screen rolling structure, and the screen rolling structure is used to synchronously roll up or release the screen and the side strip. When the screen and the side strip are in a rolled-up state, two adjacent layers of the screen are separated by the side strip; as well as A side strip rolling structure, wherein the second end of the side strip is fixed to the side strip rolling structure, and the side strip rolling structure is used to place the side strip outside when the screen rolling structure rolls up the side strip, and is used to roll up the side strip when the screen rolling structure places the side strip outside.
2. The projection screen device according to claim 1, characterized in that The edge strip rolling structure includes two bases and a rotating shaft rotatably connected between the two bases; The second end of the side strip is fixedly connected to the rotating shaft.
3. The projection screen device according to claim 2, characterized in that The side strip rolling structure is a passive structure, which is used to rotate under the drive of the screen rolling structure to roll up or release the side strip.
4. The projection screen device according to claim 3, characterized in that The edge strip rolling structure further comprises an elastic member, one end of which is fixed to one of the bases, and the other end of which is fixed to the rotating shaft; The elastic member stores or releases elastic potential energy when the rotating shaft rotates.
5. The projection screen device according to claim 2, characterized in that The side strip rolling structure is an active structure, which is used to rotate synchronously with the screen rolling structure to roll up or release the side strip.
6. The projection screen device according to claim 5, characterized in that The edge strip winding structure further includes a motor, one end of which is fixed to one of the bases, and the other end of which is fixed to the rotating shaft; The motor is used to drive the rotating shaft to rotate so as to reel in or unroll the side strip.
7. The projection screen device according to any one of claims 2 to 6, characterized in that: The projection screen device comprises two side strips, and the second ends of the two side strips are wound around the rotating shaft at intervals.
8. The projection screen device according to claim 7, characterized in that The projection screen device comprises two side strip rolling structures, and the two side strips are respectively wound on the rotating shafts of the two side strip rolling structures.
9. The projection screen device according to claim 1, characterized in that The first end of the side strip is fixed to the display surface of the screen.
10. A projection system, characterized in that: include: The projection screen device according to any one of claims 1 to 9; as well as The projector is used for projecting projection light onto the display surface of the projection screen device so that the display surface displays a projection image.