CN115407601A

CN115407601A - Projection screen and projection system

Info

Publication number: CN115407601A
Application number: CN202211238192.0A
Authority: CN
Inventors: 张益民; 陈智超; 罗坚; 胡世加
Original assignee: Chengdu Amrith Technology Co ltd
Current assignee: Chengdu Amrith Technology Co ltd
Priority date: 2022-10-11
Filing date: 2022-10-11
Publication date: 2022-11-29

Abstract

The application discloses projection screen and projection system relates to the projection display field, and projection screen has a rolling axis direction, includes: the device comprises a diaphragm, a protective film, a first winding mechanism and a second winding mechanism; the membrane is flexible, and one side of the membrane is an imaging display side; the protective film is rollable; the first winding mechanism is connected with one end of the diaphragm and one end of the protective film and controls winding/unwinding of the diaphragm and the protective film; the second winding mechanism is connected with the other end of the protective film and controls the winding/unwinding of the protective film; when the membrane is rolled, the protective film is covered on the membrane, the first rolling mechanism rolls the protective film, and the second rolling mechanism rolls the protective film; when the diaphragm is unreeled, the first reeling mechanism unreels the protection film, and the second reeling mechanism reels the protection film. This application has many times and receives and unreel the operation, the advantage of difficult fish tail.

Description

Projection screen and projection system

Technical Field

The application relates to the technical field of projection display, in particular to a projection screen and a projection system.

Background

In the prior art, in order to realize the curling function of the projection screen, people usually use a film which can be curled and has the imaging display function to manufacture the projection screen. Although the crimping function of the projection screen reduces the difficulty of transportation, storage and home installation of the projection screen, the corresponding problem is also brought, in the production, manufacturing and using processes, people can perform rolling and unreeling operations on the projection screen with the crimping function for many times, and in the rolling and unreeling processes, the imaging display surface of the projection screen is easily scratched, and the imaging display effect is influenced.

Disclosure of Invention

The application provides a projection screen can effectively solve among the prior art projection screen and carry out rolling many times, unreel the operation at rolling/unreel in-process, and the problem that projection screen's formation of image display surface is easily by the fish tail.

The technical scheme of the projection screen provided by the application is as follows:

a projection screen having a winding axis orientation, comprising: the device comprises a diaphragm, a protective film, a first winding mechanism and a second winding mechanism;

the membrane is flexible, and one side of the membrane is an imaging display side;

the protective film is rollable;

the first winding mechanism is connected with one end of the diaphragm and one end of the protective film and controls winding/unwinding of the diaphragm and the protective film;

the second winding mechanism is connected with the other end of the protective film and controls the winding/unwinding of the protective film;

when the membrane is rolled, the protective film is covered on the membrane, the first rolling mechanism rolls the protective film, and the second rolling mechanism rolls the protective film;

when the diaphragm is unreeled, the first reeling mechanism unreels the protection film, and the second reeling mechanism reels the protection film.

In the technical scheme of this application, set up the protection film, the protection diaphragm avoids rolling/unreeling the in-process, the formation of image display surface of diaphragm is by the fish tail, guarantees projection screen's formation of image display effect.

According to the technical scheme, the membrane and the protective film are wound/unwound through a first winding mechanism, and the protective film is wound/unwound through a second winding mechanism; specifically, when the membrane is rolled, the protective film is covered on the membrane, the first rolling mechanism rolls the protective film, and the second rolling mechanism rolls the protective film to protect the membrane and prevent the membrane from being scratched; when the imaging display is needed, the first winding mechanism unreels the protective film, and the second winding mechanism winds the protective film, so that the imaging display surface of the diaphragm is not affected by the protective film in the imaging display process, and the imaging display effect of the projection screen is ensured.

As an optional implementation manner, the first winding mechanism includes a first winding shaft, and the first winding shaft is connected with one end of the membrane and one end of the protective film;

the second winding mechanism comprises a second winding shaft, and the second winding shaft is connected with the other end of the protective film.

In an optional embodiment, the first winding mechanism includes a first winding shaft, the first winding shaft is connected to the membrane and the protective film, and the membrane and the protective film can be wound/unwound by controlling the first winding shaft; the second winding mechanism comprises a second winding shaft, the second winding shaft is connected with the other end of the protective film, the first winding shaft is used for realizing the unwinding of the protective film when the protective film is wound, and the first winding shaft is used for realizing the winding of the protective film when the protective film is unwound.

As an optional implementation manner, the first winding mechanism further includes a first driving mechanism, which drives the first winding shaft to move;

the second winding mechanism further comprises a second driving mechanism which drives the second winding shaft to move.

In an optional implementation manner, a first driving mechanism is arranged in the first winding mechanism, and the first driving mechanism provides a driving force for the first winding shaft to drive the first winding shaft to move, so that the film and the protective film are wound/unwound; the second driving mechanism is arranged in the second winding mechanism and used for providing driving force for the second winding shaft to drive the second winding shaft to move, when the first winding shaft is right, unwinding of the protective film is achieved, and when the first winding shaft is right, winding of the protective film is achieved.

As an alternative embodiment, the projection screen further comprises a stiffening component disposed on an opposite side of the membrane from the imaging display surface.

In an alternative embodiment, a reinforcing component is arranged on the opposite side of the imaging display surface of the membrane, so that the flatness of the membrane after being rolled and unfolded is improved.

As an optional implementation manner, the reinforcing component includes a plurality of reinforcing structures, the reinforcing structures are in a strip shape, and the extending direction of the reinforcing structures is consistent with the rolling axis direction.

In an alternative embodiment, the reinforcement assembly comprises several reinforcement structures, that is, there may be a plurality of reinforcement structures in the reinforcement assembly; the arrangement of the reinforcing structure provides a supporting force for the membrane to be rolled and unfolded, and the flatness of the membrane is improved; the reinforced structure is set to be in a long strip shape, the extending direction of the reinforced structure is consistent with the rolling axis direction, namely, the extending direction of the reinforced structure is parallel to the rolling axis direction, and resistance cannot be caused to rolling of the membrane through the arrangement mode.

Because use first rolling axle to the diaphragm when rolling, for first rolling axle, the diaphragm can be rolled into a plurality of layers, use the layer of adjacent first rolling axle as the first layer, the diaphragm can form certain clearance with first rolling axle surface in the first layer, resume the rolling again, this clearance can receive extrusion deformation, every layer that the clearance corresponds promptly can all receive extrusion deformation, thereby lead to the diaphragm to warp, especially the diaphragm of first layer clearance department warp most seriously, after the diaphragm expandes, a plurality of indentures can appear on the diaphragm, cause the serious deformation of display image, very big influence is watched and is experienced.

As an optional embodiment, in the winding axis direction, a first protrusion is arranged on the surface of the first winding shaft, and the extending direction of the first protrusion is consistent with the winding axis direction; along being perpendicular to rolling axis direction, the first arch surpasss the first maximum distance on rolling axle surface is not less than 90% of the thickness sum of diaphragm and protection film, and is not more than 1.1 times of the thickness sum of diaphragm and protection film for in the diaphragm rolling process, first arch with first rolling axle with the clearance phase-match that the diaphragm formed, effectively support the diaphragm in the diaphragm rolling process, make the diaphragm is difficult to the extrusion deformation in the rolling process, guarantee the image display effect after the diaphragm expandes.

As an alternative embodiment, the first projection is removable.

In an alternative embodiment, the first protrusion is detachable, that is, the first protrusion may be provided on the first winding shaft by bonding or the like.

As an alternative embodiment, the size of the area of the first projection on the surface of the first winding shaft is less than or equal to 50% of the size of the area of the first winding shaft.

In an optional implementation mode, the area size of the first bulge on the surface of the first winding shaft is set to be less than or equal to 50%, the first bulge is prevented from being too large, the area size of the first bulge on the surface of the first winding shaft is controlled to be smaller than or equal to 50%, the membrane is prevented from being locally extruded and deformed in the winding process, the risk of new indentation is reduced, the flatness of the membrane after unwinding is enhanced, and the image display effect of the membrane after unwinding is ensured.

As an optional embodiment, in the winding axis direction, a second protrusion is arranged on the surface of the second winding shaft, and the extending direction of the second protrusion is consistent with the winding axis; along the direction perpendicular to the winding axis, the maximum distance of the second protrusion beyond the surface of the second winding shaft is not less than 70% of the thickness of the protective film and is not more than 1.3 times of the thickness of the protective film.

In an optional embodiment, when the membrane is rolled, the protective film is covered on the membrane, the first rolling mechanism rolls the protective film, and the second rolling mechanism rolls the protective film; when imaging display is needed, the first winding mechanism unwinds the protective film, and the second winding mechanism winds the protective film; that is, the flatness of the film after being developed may be affected by the protective film exhibiting an indentation or the like. Arranging a second bulge on the surface of the second winding shaft in the winding axis direction, wherein the extending direction of the second bulge is consistent with the winding axis; along the perpendicular to rolling axis direction, the distance that the second arch surpassed second rolling axle surface is not less than 70% of the thickness of protection film, and is not more than 1.3 times of the thickness of protection film, makes second winding mechanism is in the rolling during the protection film, the second arch with first rolling axle with clearance phase-match between the protection film effectively supports the protection film, avoids the protection film is local by extrusion deformation, reduces the risk that new indentation produced, and then reduces to the influence of the diaphragm expandes back planarization, guarantees the formation of image display effect after the diaphragm is unreeled.

In addition, the application also provides a projection system, which comprises the projection screen and a projection device for projecting image light to the projection screen.

The projection system has the advantages of high image display smoothness and good imaging display effect.

The construction of the present application and other objects and advantages thereof will be apparent from the following detailed description taken in conjunction with the accompanying drawings.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.

Fig. 1 is a schematic diagram illustrating connection relationships between components of a projection screen according to a first embodiment of the present application;

fig. 2 is a schematic view illustrating a rolling state of a film sheet according to a first embodiment of the present application;

fig. 3 is a schematic diagram illustrating a film unwinding state according to a first embodiment of the present application;

fig. 4 is a first cross-sectional view illustrating relative positions of a first winding mechanism and a second winding mechanism according to a first embodiment of the present application;

fig. 5 is a schematic sectional view of the relative positions of the first winding mechanism and the second winding mechanism in the first embodiment of the present application;

fig. 6 is a schematic cross-sectional view showing relative positions of the first winding mechanism and the second winding mechanism according to the first embodiment of the present application;

fig. 7 is a cross-sectional view of the relative positions of the first winding mechanism and the second winding mechanism in the first embodiment of the present application;

FIG. 8 is a schematic view of a first winding mechanism according to a first embodiment of the present application;

FIG. 9 is a schematic view of a second winding mechanism according to a first embodiment of the present application;

fig. 10 is a first schematic view of a first winding mechanism according to a first embodiment of the present application;

fig. 11 is a second schematic view of the first winding mechanism according to the first embodiment of the present application;

FIG. 12 is another schematic view of FIG. 11;

FIG. 13 is a third schematic view of the first winding mechanism in the first embodiment of the present application;

FIG. 14 is a diagram showing the positional relationship between the reinforcing member and the diaphragm according to the second embodiment of the present application;

fig. 15 is a schematic diagram illustrating a film unwinding state according to a second embodiment of the present application;

FIG. 16 is a schematic view of a projection screen according to a third embodiment of the present application;

FIG. 17 is a schematic view of a projection screen according to a fourth embodiment of the present application;

FIG. 18 is a schematic cross-sectional view of a projection screen according to an embodiment of the present application after being rolled;

FIG. 19 is a schematic view of a fifth embodiment of the present application after the first projection has been peeled off the first take-up reel;

FIG. 20 is a first schematic view showing the combination of the first protrusion and the first take-up reel according to the fifth embodiment of the present application;

FIG. 21 is a second schematic view showing combination of first protrusions and a first take-up reel according to a fifth embodiment of the present application;

FIG. 22 is a schematic view of a fifth embodiment of the present application showing a first protrusion and an associated parameter indication;

FIG. 23 is a schematic view of a fifth embodiment of the present application after the second protrusion is peeled off from the second wind-up reel;

fig. 24 is a first schematic view of a fifth embodiment of the present application showing a second protrusion combined with a second winding shaft;

FIG. 25 is a second drawing showing the combination of the second projection and the second take-up reel in accordance with the fifth embodiment of the present application;

FIG. 26 is a schematic view of a fifth embodiment of the present application showing a second protrusion and associated parameter identifiers;

fig. 27 is a projection system according to a sixth embodiment of the present application.

Wherein, the reference numbers in the figures mean:

1000-projection screen; 110-a membrane; 120-protective film; 130-a first winding mechanism; 1301-a first winding shaft; 1302-a first drive mechanism; 13021-first handle; 13022-first coupling; 13023-first drive motor; 13024-first controller; 1303 — first projection; 140-a second winding mechanism; 1401-a second take-up reel; 1402-a second drive mechanism; 1403-second projection; 150-a reinforcement component; 1501-a reinforcing structure; 160-a cross bar; 170-a housing; 180-a lifting mechanism; 2000 — projection system; 210-a projection device; t-image light; 3000-support surface; 300-first gap.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application without making any creative effort belong to the protection scope of the present application.

In the description of the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the feature. In the description of the present application, "a number" means at least one, such as one, two, three, etc., unless specifically limited otherwise.

In this application, unless expressly stated or limited otherwise, the terms "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral combinations thereof; they may be directly connected or indirectly connected through intervening media, or they may be interconnected within two elements or in a relationship where two elements interact with each other unless otherwise specifically limited. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In the description of the present application, it is to be understood that the terms "upper", "lower", "left", "right", and the like, if any, refer to orientations or positional relationships based on those shown in the drawings, and are used merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the present application.

Example one

Fig. 1 is a schematic diagram illustrating a connection relationship between components of a projection screen according to a first embodiment of the present application, and fig. 2 is a schematic diagram illustrating a rolling state of a film in the first embodiment of the present application; fig. 3 is a schematic diagram illustrating an unwinding state of a film in an embodiment of the present application.

As shown in fig. 1, a projection screen 1000 having a winding axis direction, hereinafter denoted as x-axis, includes a film 110, a protection film 120, a first winding mechanism 130, and a second winding mechanism 140; the film 110 is flexible, so that the projection screen 1000 can be rolled and unwound conveniently, and one surface of the film 110 is an imaging display surface; the protection film 120 is also rollable, and is also convenient for rolling and unrolling the projection screen 1000; the first winding mechanism 130 is connected to one end of the diaphragm 110 and one end of the protection film 120, and is configured to control winding/unwinding of the diaphragm 110 and the protection film 120; the second winding mechanism 140 is connected to the other end of the protection film 120, and controls winding/unwinding of the protection film 120.

It should be further added that the first winding mechanism 130 controls winding/unwinding of the film 110 and the protection film 120, that is, the first winding mechanism 130 has a winding axis direction; the second winding mechanism 140 controls winding/unwinding of the protective film 120, that is, the second winding mechanism 140 has a winding axis direction; since the whole projection screen 1000 has a rolling axis direction x axis, the rolling axis direction of the first rolling mechanism 130 and the rolling axis direction of the second rolling mechanism 140 are consistent with the rolling axis direction x axis of the projection screen 1000.

It should be further added that the film 110 may be a common projection screen such as a white plastic screen, a metal screen, a glass bead screen, etc., or an optical film such as a fresnel optical screen, a linear grating screen, a photon screen, etc., and is used for image display regardless of whether the film is a functional structure layer (e.g., a diffuse reflection functional layer of the white plastic screen, a metal directional reflection layer of the metal screen, etc.) or a multi-layer functional structure layer (e.g., a diffusion layer, a color layer, a fresnel lens layer, a reflection layer of the linear grating screen, a light absorption layer, a grating structure layer, etc.), and regardless of which the film belongs to, in a multiple winding and unwinding process, there is still a problem that an image display surface of the film is easily scratched, which affects an image display effect, and therefore, the technical solution of the embodiment of the present application may be applied to solve the above problem.

Further, the material of the protective film 120 may be a flexible film material such as polyurethane, polyethylene, polypropylene, polyamide, polypropylene, polystyrene, styrene, silicone, TPU, polyvinyl chloride, neoprene, ethylene-propylene rubber, plasticized polyolefin, chlorosulfonated polyethylene, chlorinated polyethylene, butylene rubber, thermoplastic synthetic rubber, epichlorohydrin rubber, etc., so that a buffer isolation layer can be formed when the membrane 110 is wound/unwound to prevent the microstructure, burr, foreign matter, etc. from scratching the imaging display surface of the membrane; in addition, after the membrane 110 is unreeled, the stretchable protective film 120 is easily stretched, so as to reduce the tension on the membrane 110 and avoid the unevenness of the projection screen.

As shown in fig. 2, when the film is rolled, the first rolling mechanism 130 rolls the film 110, the first rolling mechanism 130 also rolls the protection film 120, and meanwhile, the second rolling mechanism 140 rolls the protection film 120, that is, when the first rolling mechanism 130 rolls the film 110, taking the x axis in the rolling axis direction as the axis, the film 110 and the protection film 120 are both rolled, and the film 110 and the protection film 120 are rolled together at intervals, that is, each roll of the film 110 is wound, and each adjacent roll of the film is the protection film 120, so reciprocating, the protection film 120 always protects the film 110, and the film 110 is prevented from being scratched during the rolling process, the film 110 is completely protected, and further, the imaging display effect of the projection screen 1000 is ensured.

As shown in fig. 3, when the film sheet 110 is unwound, the first winding mechanism 130 unwinds the film sheet 110, the first winding mechanism 130 also unwinds the protective film 120, and meanwhile, the second winding mechanism 140 winds the protective film 120, that is, when the first winding mechanism 130 unwinds the film sheet 110, the protective film 120 is in an unwinding state relative to the first winding mechanism 130 and is in a winding state relative to the second winding mechanism 140. Because the film 110 is in the winding state, each winding of the film 110 is performed, and each adjacent winding is the protection film 120, when the film 110 is in the unwinding state, each winding of the film 110 is performed, and each winding of the film 110 is performed, each protection film 120 still protects the film 110 until the film 110 and the protection film 120 are separated from each other, and the film 110 is in the completely unwinding state. In the whole unreeling process, the membrane 110 is protected by the protective film 120, so that the membrane 110 is not easily scratched in the unreeling process; in addition, the unwound film 110 avoids interference of the protective film 120 in the imaging display process, thereby ensuring the imaging display effect of the projection screen.

In the embodiment of the application, the unwinding/winding of the diaphragm 110 and the protection film 120 is realized through the arrangement of the first winding mechanism 130, the unwinding/winding of the protection film 120 is realized through the arrangement of the second winding mechanism 140, the protection film 120 always plays its function in the winding/unwinding operations for multiple times, the diaphragm 110 is protected, and the problem that the imaging display surface of the projection screen 1000 is easily scratched when the projection screen 1000 performs the winding/unwinding operations for multiple times in the winding/unwinding process in the prior art is effectively solved; meanwhile, when the projection screen 1000 performs image display, the interference of the protective film 120 on the image display effect is avoided.

When the first winding mechanism 130 is used to wind/unwind the film 110 and the protective film 120, and the second winding mechanism 140 is used to wind/unwind the protective film 120, only the winding axis direction of the first winding mechanism 130 and the winding axis direction of the second winding mechanism 140 need to be consistent with the x axis of the winding axis direction of the projection screen 1000, so that the position of the second winding mechanism 140 is not uniquely fixed.

Fig. 4 to 7 are schematic cross-sectional views of four relative positions of the first winding mechanism and the second winding mechanism according to the first embodiment of the present application.

As shown in fig. 4, the second winding mechanism 140 is located above the first winding mechanism 130; as shown in fig. 5, the second winding mechanism 140 may be located below the first winding mechanism 130; as shown in fig. 6, the second winding mechanism 140 may be located at the left side of the first winding mechanism 130; as shown in fig. 7, the second winding mechanism 140 may be located on the right side of the first winding mechanism 130. As can be seen from fig. 4 to 7, the winding axis directions of the first winding mechanism 130 and the second winding mechanism 140 are consistent no matter where the second winding mechanism 140 is located relative to the first winding mechanism 130.

Specifically, fig. 8 is a schematic view of a first winding mechanism according to the first embodiment of the present application; fig. 9 is a schematic view of a second winding mechanism according to the first embodiment of the present application.

As shown in fig. 8, the first winding mechanism 130 includes a first winding shaft 1301 and a first driving mechanism 1302, the first winding shaft 1301 is connected to one end of the film 110 and one end of the protective film 120, and the first driving mechanism 1302 provides a driving force for the first winding shaft 1301 to drive the first winding shaft 1301 to move. As shown in fig. 9, the second winding mechanism 140 includes a second winding shaft 1401 and a second driving mechanism 1402, the second winding shaft 1401 is connected to the other end of the protective film 120, and the second driving mechanism 1402 provides a driving force for the second winding shaft 1401 to drive the second winding shaft 1401 to move.

It can be known that, when the first winding mechanism 130 only includes the first winding shaft 1301, that is, the first winding mechanism 130 is the first winding shaft 1301, the movement of the first winding shaft 1301 directly depends on manual driving; similarly, when the second winding mechanism 140 only includes the second winding shaft 1401, that is, the second winding mechanism 140 is the second winding shaft 1401, the movement of the second winding shaft 1401 also depends on manual driving directly.

As shown in fig. 8, the main body of the first winding shaft 1301 is a cylinder structure, the extending direction of the arc surface of the cylinder structure is consistent with the x axis in the winding axis direction, and two shafts are arranged at two ends of the cylinder structure in the extending direction, so that the first winding shaft 1301 is limited. Similarly, as shown in fig. 9, the main body of the second winding shaft 1401 is a cylinder structure, the extending direction of the arc surface of the cylinder structure is consistent with the x axis in the winding axis direction, and two shafts are arranged at two ends of the cylinder structure in the extending direction, so that the second winding shaft 1401 is limited.

It is further explained that the unwinding/winding of the film 110 and the protective film 120 by the first winding shaft 1301 and the unwinding/winding of the protective film 120 by the second winding shaft 1401 solve the problems of the winding/unwinding of the film 110 and the protective film 120 and the easy scratching of the imaging display surface of the film 110 which is repeatedly wound/unwound during the production, manufacture and use processes, but the shape and structure of the first winding shaft 1301 are not limited to the shape shown in fig. 8, and the shape and structure of the second winding shaft 1401 are not limited to the shape shown in fig. 9. When the first winding shaft 1301 and the second winding shaft 1401 are of other structures, the above problem can be solved. Compared with other structures, the main body of the first winding shaft 1301 is in a cylindrical structure, and the main body of the second winding shaft 1401 is in a cylindrical structure, so that the processing and manufacturing are facilitated.

Further, fig. 10 is a first schematic view of a first winding mechanism according to a first embodiment of the present application; fig. 11 is a second schematic view of the first winding mechanism according to the first embodiment of the present application; FIG. 12 is another schematic view of FIG. 11; fig. 13 is a third schematic view of the first winding mechanism according to the first embodiment of the present application.

As shown in fig. 10, the first winding mechanism 130 includes a first winding shaft 1301 and a first handle 13021, where the first handle 13021 is one of the first driving mechanisms 1302, that is, the first handle 13021 is one specific example of the first driving mechanism 1302. Specifically, the first handle 13021 and the first winding shaft 1301 are connected in series, and the first winding shaft 1301 can be driven by rotating the first handle 13021, so as to wind/unwind the film 110 and the protective film 120; when the first handle 13021 provides a winding driving force for the first winding shaft 1301, the second winding shaft 1401 unwinds; when the first handle 13021 provides unwinding force to the first winding shaft 1301, the second winding shaft 140 winds, that is, the rotation directions of the first winding shaft 1301 and the second winding shaft 1401 are opposite. Similarly, the second winding mechanism 130 may also adopt such a combination (the same as the combination of the first winding mechanism 130 in fig. 10, which is not shown here) to wind/unwind the protective film 120, so as to achieve the purpose that the rotation directions of the first winding shaft 1301 and the second winding shaft 1401 are opposite.

As shown in fig. 11, the first winding mechanism 130 includes a first winding shaft 1301, a first handle 13021, and a first coupler 13022, the first winding shaft 1301 and the first handle 13021 are connected in series through the first coupler 13022, and the first winding shaft 1301 is driven by manually driving or otherwise rotating the first handle 13021, so as to wind/unwind the film 110 and the protective film 120.

As shown in fig. 12, on the basis of fig. 11, a first handle 13021 can be arranged on a supporting surface 3000, and by means of the supporting surface 3000, the situation that the first handle 13021 is connected with the first winding shaft 1301 and separated when the driving force is provided is avoided.

As shown in fig. 13, the first winding mechanism 130 includes a first winding shaft 1301, a first coupling 13022, a first driving motor 13023, and a first controller 13024, the first winding shaft 1301 and the first driving motor 13023 are connected in series through the first coupling 13022, the first controller 13024 controls the first driving motor 13023 in a wireless or wired manner, and specifically, the first controller 13024 controls the start, stop, reverse rotation, forward rotation, rotation speed and the like of the first driving motor 13023 to control the first winding shaft 1301, thereby further realizing the winding and unwinding operations of the first winding shaft 1301 on the film 110 and the protective film 120. Here, the first driving motors 13023 select an appropriate number according to the different types and types of the selected motors, so as to realize the winding/unwinding functions of the first winding shaft 1301 on the membrane 110 and the protective film 120, and no transition arrangement is needed, thereby avoiding resource waste.

It should be noted that the second rolling mechanism 140 may also be configured as the above combination of the first rolling mechanism 130, but it should be noted that when the first rolling mechanism 130 rolls the film 110 and the protective film 120, the second rolling mechanism 140 rolls the protective film 120; when the first winding mechanism 130 winds, the second winding mechanism 140 winds the protective film 120, that is, the rotation directions of the first winding shaft 1301 and the second winding shaft 1401 are opposite, that is, the driving force provided by the first driving mechanism 1302 to the first winding shaft 1301 and the driving force provided by the second driving mechanism 1402 to the second winding shaft 1401 are opposite.

Example two

FIG. 14 is a diagram showing a positional relationship between a reinforcing member and a diaphragm according to a second embodiment of the present application; fig. 15 is a schematic view illustrating a film unwinding state in the second embodiment of the present application. In addition to the first embodiment, the projection screen 1000 further includes a reinforcing member 150, and the reinforcing member 150 is disposed on the opposite side of the imaging display surface of the diaphragm 110.

As shown in fig. 14, a reinforcing member 150 is provided on the opposite side of the image display surface of the film 110 to improve the flatness of the rolled film 110 after it is rolled.

Specifically, the reinforcing component 150 includes several reinforcing structures 1501, that is, the reinforcing structures 1501 may be multiple; the arrangement of the reinforcing structure 1501 provides a supporting force for the membrane 110 to be rolled and then unfolded, and improves the flatness of the membrane 110; the reinforcing structure 1501 is arranged in a long strip shape, and the extending direction of the reinforcing structure 1501 is consistent with the x axis in the rolling axis direction, that is, the extending direction of the reinforcing structure 1501 is consistent with the x axis, and this arrangement mode does not provide resistance to rolling of the membrane 110; use perpendicular to rolling axis direction as the y axle, reinforced structure 1501 is used for providing diaphragm 110 at the bending strength of x axle, y axle for expand again after the rolling of diaphragm 110, level and smooth non-deformable, and then make formation of image display image non-deformable, whole picture is level and smooth.

Further, after the projection screen 1000 is hung or supported, the reinforcing structure 1501 can provide an acting force resisting deformation of the diaphragm 110 for the diaphragm 110, so that the diaphragm 110 is more flat, and flatness of the whole projection screen 1000 is further ensured.

Specifically, the reinforcing structure 1501 may be a triangular prism structure, and the cross-sectional shape in the y-axis is a triangle; the reinforcing structure 1501 may be an arc-shaped columnar structure, with the cross-sectional shape in the y-axis being an arc; the reinforcing structure 1501 may also be a rectangular parallelepiped structure, with a rectangular cross-section in the y-axis; the reinforcing structure 1501 may also be a trapezoidal pillar structure, a cross-sectional shape in the y-axis is trapezoidal, and so on, which are not listed here. The cross-sectional shape of the reinforcing member 150 in the y-axis may be a combination of any one of the above cross-sectional shapes arranged adjacently or at intervals, a combination of any two of the above cross-sectional shapes arranged adjacently or at intervals, or a combination of three or more of the above cross-sectional shapes.

By providing the reinforcing structure 1501 with the cross-sectional shape as described above, the bending strength of the reinforcing structure 1501 is enhanced, and the dependence of the reinforcing structure 1501 on the material itself is reduced, for example, when the material of the reinforcing structure 1501 is selected, the bending strength of the material itself is no longer required to be greater than the bending strength of the membrane 110, so that the material selection range of the reinforcing structure 1501 is widened, and the material selection has more universal applicability. Specifically, the reinforced structure 1501 can be selected from non-metallic materials such as PET, PC, PMMA, paper, and can also be selected from common metallic materials such as aluminum and copper, so that the implementation is more convenient, and the practicability is higher.

In order to enhance the bending strength of the reinforcing component 150, it is preferable that the reinforcing structure 1501 is a triangular prism structure, the cross-sectional shape of the y-axis is a triangle, the stability of the triangle is high, the bending strength of the reinforcing structure 1501 can be improved, and the bending strength of the whole reinforcing component 150 can be improved, and the size of the reinforcing structure 1501 can be changed by adjusting the vertex angle and the side length of the triangle, so that the manufacturing difficulty of the reinforcing component 150 and the projection screen 1000 is reduced.

As shown in fig. 15, the first winding mechanism 130 is connected to one end of the film 110 and one end of the protection film 120, when the first winding mechanism 130 unwinds the film 110 and the protection film 120, the reinforcing element 150 unwinds along with unwinding of the film 110, the second winding mechanism 140 winds the protection film 120, and the reinforcing element 150 provides an acting force for resisting deformation of the film 110 for the film 110, so that the film 110 is smoother, and flatness of the whole projection screen 1000 is further ensured.

When the first winding mechanism 130 winds the membrane 110 and the protection film 120, the reinforcing component 150 is also wound along with the winding of the membrane 110, the x axis in the winding axis direction is taken as an axis, the membrane 110, the reinforcing component 150 and the protection film 120 are all curled, and the membrane 110, the reinforcing component 150 and the protection film 120 are curled together at intervals, that is, each winding circle of the membrane 110 is adjacent to one another, the adjacent circles of the membrane 110 are the reinforcing component 150 and then are the protection film 120, the imaging display surfaces of the reinforcing component 150 and the membrane 110 are not in contact all the time, and the protection film 120 is repeated in this way, so that the membrane 110 is protected all the time by the protection film 120, the membrane 110 is prevented from being scratched in the winding process, the membrane 110 is completely protected, and the imaging display effect of the projection screen 1000 is further ensured.

Further, a cross bar 160 may be disposed at an end of the film 110 away from the first rolling mechanism 130, and when the projection screen 1000 is used for hanging, a certain pulling force may be generated on the projection screen 1000 by the weight of the cross bar 160, so as to further flatten the projection screen 1000. That is, the cross bar 160 may have various shapes, such as a cylindrical shape, a rectangular parallelepiped shape, etc., and it is mainly required to have a certain weight and a certain size to improve the installation flatness of the projection screen 1000, that is, the installation flatness of the projection screen 1000 can be improved by adjusting the weight and the size of the cross bar 160.

It is further noted that the cross bar 160 is connected to the membrane 110 by any one of clamping, gluing, or nailing.

EXAMPLE III

Fig. 16 is a schematic view of a projection screen according to a third embodiment of the present application. On the basis of the second embodiment, a casing 170 is provided, and the casing 170 is used for accommodating the rolled projection screen 1000 and is applied to a hanging screen.

Specifically, the wall surface is used as the mounting surface, the mounting position of the cabinet 170 is used as the upper end, and the rail 160 of the unreeled projection screen 1000 is used as the lower end. The size of the casing 170 is larger than the size of the projection screen 1000 after being rolled by other structures except the cross bar 160, and a space for the protective film 120 to be rolled by the first rolling shaft 1301 and the second rolling shaft 1401 is reserved; the two ends of the casing 170 are provided with holes, so that the projection screen 1000 can be conveniently installed and fixed on a wall surface; the housing 170 is provided with an opening to facilitate the entrance and exit of the diaphragm 110 and the reinforcement member 150; the opening of the housing 170 is slightly smaller than the size of the cross bar 160.

That is to say, when the image display is not needed, the projection screen 1000 is rolled, the first rolling shaft 1301 rolls the protective film 120 and the diaphragm 110 at the same time, the second rolling shaft 1401 rolls the protective film 120, and the cross bar 160 is used for rolling and blocking, and plays a limiting function, that is, the cross bar 160 is rolled in place immediately after abutting against the casing 170, and other structures of the rolled projection screen 1000 are located in the casing 170 except for the limiting cross bar 160, so that the attractiveness of the rolled projection screen 1000 is enhanced. When the image display is needed, the projection screen 1000 is unreeled, the first reeling shaft 1301 simultaneously unreels the protective film 120 and the diaphragm 110, and the second reeling shaft 1401 reels the protective film 120, and as the cross rod 201 has a certain weight, the image display surface of the diaphragm 110 can be quickly lowered to a set position from the casing 170, and the reeling and unreeling processes of the protective film 120 are all completed in the casing 170, so that the attractiveness of the projection screen 1000 is ensured.

Example four

Fig. 17 is a schematic view of a projection screen according to a fourth embodiment of the present application. The difference from the third embodiment is that the projection screen 1000 is additionally provided with a lifting mechanism 180, and the lifting mechanism is applied to lifting the screen.

Specifically, with reference to the horizontal plane, when the image display is not required, the projection screen 1000 is rolled and located at the horizontal plane, when the image display is required, the uppermost end of the projection screen 1000 is far away from the horizontal plane, the housing 170 is located at the horizontal plane, i.e., the bottom, and the cross bar 160 is located at the uppermost end, i.e., the top, of the projection screen 1000. The size of the casing 170 is larger than the size of the projection screen 1000 after being rolled by other structures except the cross bar 160, and a space for the protective film 120 to be rolled by the first rolling shaft 1301 and the second rolling shaft 1401 is reserved; the housing 170 is provided with an opening for facilitating the entrance and exit of the diaphragm 110 and the reinforcement member 150; the opening of the housing 170 is slightly smaller than the dimension of the cross bar 160.

That is to say, when the image display is not needed, the projection screen 1000 is rolled, the first rolling shaft 1301 rolls the protective film 120 and the diaphragm 110 at the same time, the second rolling shaft 1401 rolls the protective film 120, and the cross bar 160 is used for rolling and clamping, so as to perform a limiting function, that is, the cross bar 160 is rolled in place immediately after abutting against the casing 170, and other structures of the rolled projection screen 1000 except the limited cross bar 160 are all located on the casing 170, so that the aesthetic property of the rolled projection screen 1000 is enhanced. When the image display is needed, the projection screen 1000 is unreeled, the first reeling shaft 1301 simultaneously unreels the protective film 120 and the diaphragm 110, the second reeling shaft 1401 reels the protective film 120, the image display surface of the diaphragm 110 is lifted from the casing 170 to reach the size of the viewing picture under the action of the lifting mechanism 180, the reeling and unreeling processes of the protective film 120 are all completed in the casing 170, and the attractiveness of the projection screen 1000 is guaranteed.

At this time, the rail 160 is connected to the elevating mechanism 180, and transmits the supporting force to the entire projection screen 1000, so that the projection screen 1000 is maintained flat.

As a supplementary description, the lifting mechanism 180 may be a crank arm type, a column type, a scissor type, or other structures, which are not illustrated herein. The control method of the elevating mechanism 180 may be manual control or electric control.

EXAMPLE five

Fig. 18 is a schematic cross-sectional view of a projection screen according to an embodiment of the present application after being rolled. The first winding shaft 1301 is used for winding the diaphragm 110, and it can be seen that, relative to the first winding shaft 1301, the diaphragm 110 is wound into a plurality of layers, and a first gap 300 is formed between the diaphragm 110 and the surface of the first winding shaft 1301 in the first layer by using the first winding shaft 1301 as a first layer, and then the winding is continued, and the gap 300 is extruded and deformed, that is, each layer corresponding to the first gap 300 is extruded and deformed, so that the diaphragm 110 is deformed, especially the diaphragm 110 of the first layer corresponding to the first gap 300 is deformed most seriously, after the diaphragm 110 is unfolded, the diaphragm 110 has a plurality of indentations, which are deformation difficult to reverse, so that the displayed image is deformed seriously, and the viewing experience is greatly influenced.

In order to solve the problem of local indentations on the diaphragm 110, the fifth embodiment of the present application provides the following solution.

Since the shape of the first winding shaft 1301 is different and the shape of the first gap 300 is also different, in order to better describe the technical solution of the embodiment, the first winding shaft 1301 is taken as a cylindrical structure for example to be explained in detail.

Fig. 19 is a schematic view of a fifth embodiment of the present application after the first protrusion is peeled from the first wind-up shaft; fig. 20 is a first schematic view illustrating combination of a first protrusion and a first winding shaft according to a fifth embodiment of the present application; fig. 21 is a second schematic view illustrating the combination of the first protrusions and the first winding shaft according to the fifth embodiment of the present application; fig. 22 is a schematic view of a first bump and a related parameter mark in the fifth embodiment of the present application.

On rolling axis direction is the x axle, set up first arch 1303 on the surface of first rolling axle 1301, the extending direction of first arch 1303 is unanimous with the x axle, because first rolling axle 1301 is the cylinder structure, then first arch 1303 is the arc arch, make in the rolling process of diaphragm 110, first arch 1303 and first clearance 300 phase-match, effectively support diaphragm 110 at rolling diaphragm 110 in-process, make diaphragm 110 be difficult to the extrusion deformation, thereby solved in the first embodiment after projection screen curls and expands again, many indentation problems that run through appear along projection screen 1000 rolling axis direction is the x axle, guarantee the image display effect after diaphragm 110 expands.

The first surface of the first protrusion 1303 contacts and is tangent to the circumferential surface of the first winding shaft 1301, the second surface of the first protrusion 1303 is called a surface opposite to the first surface of the first protrusion 1303, one end of the second surface of the first protrusion 1303 is overlapped with one end of the first surface of the first protrusion 1303, which is called an overlapping point, and then the first protrusion is gradually separated, the perpendicular distance between the second surface of the first protrusion 1303 and the first surface of the first protrusion 1303 is gradually increased, the farthest end of the first protrusion 133 from the overlapping point is taken as a y-axis, the distance of the first protrusion 1303 beyond the surface of the first winding shaft 1301 is H, the thickness of the film 110 is L, and the thickness of the protective film 120 is P.

Selecting 1-10 projection screen samples in the fifth embodiment of the application, setting that the H of each sample is different, and setting that other performance parameters are identical, respectively performing winding and unwinding operations for 200 times, 1000 times and 5000 times (the winding and unwinding operations for 1 time include complete winding and unwinding operations), finally unwinding and unwinding, and recording the appearance change condition of the projection screen, wherein the specific recording result is shown in table 1.

TABLE 1 variation of appearance of projection screen

As can be seen from the test data in table 1, when H is too small, a larger first gap 300 is formed between the first protrusion 1303, the first winding shaft 1301 and the diaphragm 110, and after the diaphragm 110 is wound, the diaphragm 110 in the first gap 300 is extruded and deformed again, and an indentation still exists; when H is too large, a larger first gap 300 is also formed between the first protrusion 1303, the first winding shaft 1301 and the film 110, and after the film 110 is wound, the film 110 at the first gap 300 is extruded and deformed again, and the indentation still exists.

Therefore, the following conditions are satisfied by the settings H, L, and P: (L + P) x (1-10%) ≦ H ≦ L + P) x (1 + 10%), i.e., along the y-axis, the maximum distance H of the first protrusion 1303 beyond the surface of the first winding shaft 1301 is not less than 90% of the sum of the thickness L of the film sheet 110 and the thickness P of the protective film 120 and is not more than 1.1 times the sum of the thickness L of the film sheet 110 and the thickness P of the protective film 120; in this scope, first arch 1303 and first clearance 300 phase-match can effectively support diaphragm 110 at diaphragm 110 rolling in-process for diaphragm 110 is difficult to extrusion deformation in the rolling in-process, is difficult for producing the indentation, guarantees the image display effect after diaphragm 110 expandes.

Further, the first protrusion 1303 is arranged on the surface of the first winding shaft 1301, and the first protrusion 1303 is detachably connected with the first winding shaft 1301, that is, the first protrusion 1303 is detachable, for example, the first protrusion 1303 may be adhered to the surface of the first winding shaft 1301, may be arranged on the surface of the first winding shaft 1301 by means of nut locking, and may be locked to the surface of the first winding shaft 1301 by means of a buckle, in short, the first protrusion 1303 and the first winding shaft 1301 are two independent blocks, and may be in a column shape by means of movable connection. Thus, when the first bumps 1303 are needed, the first bumps 1303 are arranged on the surface of the first winding shaft 1301, and when the first bumps 1303 are not needed, the first bumps 1303 can be separated from the surface of the first winding shaft 1301; when the size of the projection screen 1000 is different, the first winding shaft does not need to be replaced, the projection screen with different sizes can be adapted only by replacing the first protrusion 1303, and the cost can be saved for the product series with more projection screens.

Further, the first protrusions 1303 may also be directly welded to the surface of the first winding shaft 1301, or may also be directly formed integrally with the first winding shaft 1301. Thus, when the first winding shaft 1301 is used, the first protrusions 1303 and the first winding shaft 1301 do not need to be installed, and the winding shaft can be used directly, so that the first winding shaft 1301 can be used more conveniently.

Further, the area size of the first protrusions 1303 on the surface of the first winding shaft 1301 is less than or equal to 50% of the area size of the first winding shaft 1301, and when the area size of the first protrusions 1303 on the surface of the first winding shaft 1301 exceeds 50% of the area size of the first winding shaft 1301, a sudden height change is easily generated on the circumferential surface of the first winding shaft 1301, so that the problem that an indentation is generated after the membrane 110 is curled is solved, therefore, the first protrusions 1303 are prevented from being too large, the area size of the first protrusions 1303 on the surface of the first winding shaft 1301 is controlled, the local extrusion deformation of the membrane 110 in the winding process is avoided, the risk of generating a new indentation is reduced, the flatness of the membrane 110 after being unwound is enhanced, and the image display effect of the membrane 110 after being unwound is ensured.

When the membrane 110 is rolled, the protective film 120 covers the membrane 110, the first rolling shaft 1301 rolls the protective film 120, and the second rolling shaft 1401 rolls the protective film 120; when imaging display is needed, the first winding shaft 1301 winds the protective film 120, and the second winding shaft 1401 winds the protective film 120; that is, when the protective film 120 has a certain thickness, the flatness of the film 110 after being stretched may be affected by the indentation of the protective film 120. To solve the occurrence of avoiding such a possibility, a second projection is provided on the second take-up reel 1401. In order to better explain the technical solution of the embodiment, the second winding shaft 1401 is taken as a cylindrical structure as an example for detailed explanation.

Fig. 23 is a schematic view of a fifth embodiment of the present application after a second protrusion is peeled from a second wind-up shaft; fig. 24 is a first schematic view illustrating a combination of a second protrusion and a second winding shaft according to a fifth embodiment of the present application; fig. 25 is a second schematic view illustrating a combination of a second protrusion and a second winding shaft according to a fifth embodiment of the present application; fig. 26 is a schematic diagram of a second protrusion and a related parameter identifier according to a fifth embodiment of the present application.

On rolling axis direction is the x axle, set up second arch 1403 on the surface of second rolling axle 1401, the extending direction of second arch 1403 is unanimous with the x axle, because second rolling axle 1401 is the cylinder structure, then second arch 1403 is the arc arch, makes second rolling axle 1401 in the in-process of rolling protection film 120, and second arch 1403 effectively supports protection film 120, makes protection film 120 be difficult to extrusion deformation, thereby avoids situations such as indentation appear in protection film 120, reduces the influence to the planarization after diaphragm 110 expandes.

The second protrusion 1403 also has two surfaces relative to the circumferential surface of the second winding shaft 1401, the first surface of the second protrusion 1403 is in contact with and tangent to the circumferential surface of the second winding shaft 1401, the second surface of the second protrusion 1403 is called a surface opposite to the first surface of the second protrusion 1403, one end of the second surface of the second protrusion 1403 is overlapped with one end of the first surface of the second protrusion 1403 and is a coincident point, then the second protrusion 1403 is gradually separated, the vertical distance from the second surface of the second protrusion 1403 to the first surface of the second protrusion 1403 is gradually increased, the farthest end of the second protrusion 1403 from the coincident point is recorded, and the distance from the second protrusion 1403 to the surface of the second winding shaft 1401 is D along the direction perpendicular to the winding axis, namely the y axis.

When D is too small, a larger second gap is formed between the second protrusion 1403, the second winding shaft 1401 and the film 110, and after the protective film 120 is wound, the protective film 120 at the second gap is extruded and deformed again, and the indentation still exists; when D is too large, a larger second gap is formed between the second protrusion 1403, the second winding shaft 1401 and the film 110, and after the protective film 120 is wound, the protective film 120 at the second gap is again deformed by extrusion, and the indentation still exists.

Therefore, the relationship between D and P satisfies the following condition: d is more than or equal to 0.7P and less than or equal to 1.3P, namely along the y axis, the maximum distance D of the second projection 1403 exceeding the surface of the second winding shaft 1401 is not less than 70 percent of the thickness P of the protective film 120 and is not more than 1.1 times of the thickness P of the protective film 120; in this range, the second protrusion 1403 is matched with the second gap, and in the process of winding the protective film 120 by the second winding shaft 1401, the second protrusion 1403 can effectively support the protective film 120, so that the protective film 120 is not easily extruded and deformed in the winding process, and is not easily indented, thereby ensuring the image display effect of the expanded membrane 110.

Further, a second protrusion 1403 is arranged on the surface of the second winding shaft 1401, and the second protrusion 1403 and the second winding shaft 1401 are detachably connected, that is, the second protrusion 1403 is detachable, for example, the second protrusion 1403 can be adhered to the surface of the second winding shaft 1401, can be arranged on the surface of the second winding shaft 1401 by means of nut locking, and can be locked to the surface of the second winding shaft 1401 by means of buckle locking, in short, the second protrusion 1403 and the second winding shaft 1401 are two independent blocks, and can be columnar together by means of movable connection. In this way, when the second projection 1403 is required, the second projection 1403 is provided on the surface of the second winding shaft 1401, and when the second projection 1403 is not required, it can be separated from the surface of the second winding shaft 1401; when the size of the projection screen 1000 is different, the second winding shaft 1401 does not need to be replaced, and the projection screen with different sizes can be adapted only by replacing the second protrusion 1403, so that the cost can be saved for product series with more projection screens.

Further, the second protrusion 1403 may also be directly welded to the surface of the second winding shaft 1401, or may also be directly integrally formed with the second winding shaft 1401. Thus, when the second winding shaft 1401 is used, the second projection 1403 and the second winding shaft 1401 do not need to be installed, and the second winding shaft 1401 can be used directly, so that the second winding shaft 1401 is more convenient to use.

EXAMPLE six

Fig. 27 is a projection system according to a sixth embodiment of the present application. The projection system 2000 includes the projection screen 1000 and the projection device 210 according to any one of the first to fifth embodiments, the projection device 210 projects the image light T onto the projection screen 1000, and the image light T is imaged to the visible area of the viewer through the projection screen 1000 and received by the viewer. The specific structure and the winding and unwinding process of the projection screen 1000 are described in detail in the foregoing, and are not repeated here. The projection system is high in image display smoothness and good in imaging display effect.

The projector 1200 may be any one of a long-focus projector, a short-focus projector, and an ultra-short-focus projector; the projector light source can be a laser light source and an LED light source, and the laser light source can be a monochromatic laser, a bicolor laser or a tricolor laser.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A projection screen having a winding axis direction, comprising: the device comprises a diaphragm, a protective film, a first winding mechanism and a second winding mechanism;

the membrane is rollable, and one surface of the membrane is an imaging display surface;

the protective film is rollable;

the second winding mechanism is connected with the other end of the protective film and controls the winding/unwinding of the protective film; when the membrane is rolled, the protective film is covered on the membrane, the first rolling mechanism rolls the protective film, and the second rolling mechanism unreels the protective film;

when the membrane is unreeled, the first reeling mechanism unreels the protection film, and the second reeling mechanism reels the protection film.

2. The projection screen of claim 1, wherein the first winding mechanism comprises a first winding shaft, and the first winding shaft is connected with one end of the membrane and one end of the protective film;

3. The projection screen of claim 2, wherein the first winding mechanism further comprises a first driving mechanism for driving the first winding shaft to move;

4. The projection screen of claim 1 further comprising a stiffening assembly disposed opposite the imaging display surface of the membrane.

5. The projection screen of claim 4 wherein the reinforcement assembly comprises a plurality of reinforcing structures, the reinforcing structures being elongated and extending in a direction that is substantially aligned with the roll axis.

6. The projection screen of claim 2 wherein the first winding shaft surface is provided with first protrusions in the winding axis direction, and the extending direction of the first protrusions is consistent with the winding axis direction; the maximum distance of the first bulge exceeding the surface of the first winding shaft along the direction perpendicular to the winding axis is not less than 90% of the sum of the thicknesses of the membrane and the protective film and not more than 1.1 times of the sum of the thicknesses of the membrane and the protective film.

7. The projection screen of claim 6 wherein the first projection is removable.

8. The projection screen of claim 6 wherein the first projection has an area dimension on the surface of the first take up reel that is less than or equal to 50% of the area dimension of the first take up reel.

9. The projection screen of claim 2 wherein the second take-up shaft surface is provided with second protrusions in the take-up axis direction, the second protrusions extending in the same direction as the take-up axis; the maximum distance of the second protrusion beyond the surface of the second winding shaft along the direction perpendicular to the winding axis is not less than 70% of the thickness of the protective film and not more than 1.3 times of the thickness of the protective film.

10. A projection system comprising a projection screen according to any one of claims 1 to 9 and a projection device for projecting image light onto the projection screen.