Projection equipment and projection system

Abstract

The invention provides projection equipment and a projection system, and the projection equipment comprises a lens unit, the lens unit comprises a housing and a lens group arranged in the housing, the lens group comprises a rear group lens group, the rear group lens group comprises a rear group lens and a rear group lens barrel, the rear group lens is installed in the rear group lens barrel, and the rear group lens barrel is provided with an installation part matched with the housing; the lighting unit comprises a lighting shell; the heat balance unit is located between the lighting shell and the rear group lens cone, the heat balance unit comprises a first elastic piece and a heat conduction ring, the first elastic piece and the heat conduction ring are arranged on the rear group lens cone in a sleeving mode, and the inner edge of the heat conduction ring is connected with the side wall of the rear group lens cone in a sleeving mode. According to the invention, temperature balance of the whole system is realized, and the problem of thermal out-of-focus caused by too high temperature of the rear lens group is solved.

Description

Technical Field

[0001] The present invention relates to the field of projection technology, and in particular to a projection device and a projection system. Background Art

[0002] The projection system mainly includes the projection equipment and the projection screen. In the precision projection equipment, with the demand for miniaturization and low-cost strategic route of projection equipment products, the lens, as a key part of the projection equipment engine, will also be designed in the direction of miniaturization and low cost.

[0003] At present, projection equipment generally includes a lens unit and an illumination unit. The illumination optical path and other components in the illumination unit can provide light as a light source. The lens unit can focus the emitted light on the projection screen through refraction between different lenses, thereby displaying a normal picture. Considering the requirement of low cost, the lens barrel is generally made of plastic material. Since the thermal conductivity of plastic is much lower than that of metal lens barrel, the temperature of the entire rear lens barrel and the internal lenses will rise.

[0004] However, with existing projection equipment, as the temperature rises, the distance between the last lens in the rear group and the flange surface will increase or decrease. Adapting the original lighting system will certainly result in a decrease or increase in the back focus, leading to thermal focus shift and poor picture resolution. Summary of the invention

[0005] The main purpose of the present invention is to provide a projection device and a projection system to achieve temperature balance of the entire system and solve the problem of thermal focus deviation caused by excessive temperature of the rear group lens assembly.

[0006] To achieve the above object, in a first aspect, the present invention provides a projection device, comprising:

[0007] A lens unit, the lens unit comprises a housing and a lens group arranged in the housing, the lens group comprises a rear group lens group, the rear group lens group comprises a rear group lens and a rear group lens barrel, the rear group lens is installed in the rear group lens barrel, and the rear group lens barrel has a mounting portion adapted to the housing;

[0008] A lighting unit, the lighting unit comprising a lighting housing;

[0009] A thermal balance unit is located between the lighting housing and the rear group lens barrel. The thermal balance unit includes a first elastic member and a heat-conducting ring. Both the first elastic member and the heat-conducting ring are sleeved on the rear group lens barrel. The inner edge of the heat-conducting ring is sleeved on the side wall of the rear group lens barrel. The heat-conducting ring has a first side wall facing the lighting housing and a second side wall away from the lighting housing. The first side wall and the lighting housing are in abutment with each other for heat conduction. The first elastic member is in abutment between the end face of the mounting portion and the second side wall. The first elastic member is retractable in the direction of light incidence to establish a heat-conducting connection between the mounting portion and the lighting housing.

[0010] The beneficial effects of the present invention are as follows: Through the setting of the thermal balance unit, the temperature of the rear group lens barrel can be effectively transferred to the lighting housing, achieving temperature balance of the entire system. Through the setting of the added first elastic member, it is ensured that the mounting portion can always transfer the heat of the rear group to the heat conduction ring through the first elastic member. Among them, the temperature of the rear group is transferred to the end face portion of the first elastic member through the mounting portion, and then the first elastic member transfers the temperature to the heat conduction ring through the other end face. The heat conduction ring is in contact with the lighting housing, so that the heat is fully thermally balanced with the lighting housing, ultimately solving the problem of thermal defocus caused by too high temperature of the rear group lens group.

[0011] On the basis of the above technical solutions, the present invention can be further improved as follows.

[0012] In some alternative embodiments, the distance between the end face of the mounting portion and the end face of the lighting housing is ≤ 1 mm;

[0013] The thickness range of the first elastic member is 0.05 mm - 0.1 mm.

[0014] In some alternative embodiments, the first elastic member includes a first heat conduction portion and a second heat conduction portion. The first heat conduction portion abuts against the end face of the mounting portion, and the second heat conduction portion abuts against the second side wall. The first elastic member is used to transfer the heat between the rear group lens barrel and the heat conduction ring.

[0015] In some alternative embodiments, the first elastic member further includes a telescopic portion. The telescopic portion is located between the first heat conduction portion and the second heat conduction portion, and the opposite ends of the telescopic portion are respectively connected to the first heat conduction portion and the second heat conduction portion.

[0016] In some alternative embodiments, the cross-section of the first elastic member is annular. When the second side wall of the heat conduction ring and the end face of the mounting portion are mutually extruded, the first elastic member deforms.

[0017] In some alternative embodiments, the thermal balance unit further includes a second elastic member. The second elastic member is disposed on the flange surface of the housing and faces the first elastic member. The first elastic member is located between the second elastic member and the heat conduction ring;

[0018] The second elastic member has elasticity along the incident direction of the light and is used to tightly abut against the heat conduction ring on the end face of the lighting housing.

[0019] In some alternative embodiments, the second elastic member is an annular member. The second elastic member has a bent portion formed by surrounding the center of the second elastic member, and the distances between the various parts of the bent portion and the wall surface of the heat conduction ring are different.

[0020] In some alternative embodiments, the thermal balance unit further includes a snap ring. A slot is provided on the rear group lens barrel, and the snap ring is clamped in the slot;

[0021] Along the radial direction of the rear lens barrel, at least part of the snap ring protrudes from the notch of the card slot and is used to fix the heat conduction ring.

[0022] In a second aspect, the present invention further provides a projection device, including:

[0023] A lens unit, which includes a housing, rear group lenses disposed inside the housing, and a rear lens barrel. The rear group lenses are installed inside the rear lens barrel, and the rear lens barrel has a mounting portion adapted to the housing;

[0024] An illumination unit, which includes an illumination housing;

[0025] A heat balance unit, which is located between the end face of the illumination housing and the rear lens barrel. The heat balance unit includes a first elastic member and a heat conduction ring. The first elastic member abuts between the end face of the mounting portion and the wall surface of the heat conduction ring. The inner edge of the heat conduction ring is sleeved with the side wall of the rear lens barrel and is used to transfer the heat between the rear lens barrel and the illumination housing.

[0026] In a third aspect, the present invention further provides a projection system, including a projection screen and a projection device. The projection device is used to project a projection image onto the projection screen.

[0027] The projection device and projection system provided by the present invention, the projection system includes a projection screen and a projection device, and the projection device is used to project a projection image onto the projection screen. Among them, the projection device includes: a lens unit, the lens unit includes a housing and a lens group disposed inside the housing, the lens group includes a rear group lens group, the rear group lens group includes rear group lenses and a rear lens barrel, the rear group lenses are installed inside the rear lens barrel, and the rear lens barrel has a mounting portion adapted to the housing; an illumination unit, the illumination unit includes an illumination housing; a heat balance unit, the heat balance unit is located between the illumination housing and the rear lens barrel, the heat balance unit includes a first elastic member and a heat conduction ring, both the first elastic member and the heat conduction ring are sleeved on the rear lens barrel, the inner edge of the heat conduction ring is sleeved with the side wall of the rear lens barrel, and the heat conduction ring has a first side wall facing the illumination housing and a second side wall facing away from the illumination housing, the first side wall abuts against the illumination housing for heat conduction; the first elastic member abuts between the end face of the mounting portion and the second side wall, and the first elastic member is telescopic in the light incident direction to conduct heat between the mounting portion and the illumination housing.

[0028] Through the setting of the heat balance unit, the temperature of the rear lens barrel can be effectively transferred to the illumination housing to achieve the temperature balance of the entire system. Through the setting of the added first elastic member, it is ensured that the mounting portion can always transfer the heat of the rear group to the heat conduction ring through the first elastic member. Among them, the temperature of the rear group is transferred to the end face part of the first elastic member through the mounting portion, and then the first elastic member transfers the temperature to the heat conduction ring through the other end face. The heat conduction ring is in contact with the illumination housing, so that the heat is fully balanced with the illumination housing, and finally the problem of thermal defocus caused by the too high temperature of the rear group lens group is solved. Brief Description of the Drawings

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0030] Figure 1 It is a cross-sectional view of a lens unit in a projection device provided by the prior art;

[0031] Figure 2 It is a cross-sectional view of a projection device provided by the prior art;

[0032] Figure 3 It is a schematic structural diagram of a projection device provided by an embodiment of the present application;

[0033] Figure 4 It is an exploded view of a first projection device provided by an embodiment of the present application;

[0034] Figure 5 It is a partial cross-sectional view of a first projection device in an exploded state provided by an embodiment of the present application;

[0035] Figure 6 It is a partial cross-sectional view of a first projection device provided by an embodiment of the present application;

[0036] Figure 7 It is a schematic structural diagram of a first elastic member in a first projection device provided by an embodiment of the present application;

[0037] Figure 8 It is a partial structural schematic diagram of a first elastic member in a first projection device provided by an embodiment of the present application;

[0038] Figure 9 It is an exploded view of a second projection device provided by an embodiment of the present application;

[0039] Figure 10 It is a partial cross-sectional view of a second projection device in an exploded state provided by an embodiment of the present application;

[0040] Figure 11 It is a partial cross-sectional view of a second projection device provided by an embodiment of the present application;

[0041] Figure 12 It is an exploded view of a third projection device provided by an embodiment of the present application;

[0042] Figure 13 It is a partial cross-sectional view of a third projection device in an exploded state provided by an embodiment of the present application;

[0043] Figure 14 It is a partial sectional view of the third projection device provided by the embodiment of the present application;

[0044] Figure 15 It is a partial sectional view of the exploded state of the fourth projection device provided by the embodiment of the present application;

[0045] Figure 16 It is a partial sectional view of the fourth projection device provided by the embodiment of the present application.

[0046] Explanation of reference numerals:

[0047] 100 - Projection device;

[0048] 110 - Lens unit;

[0049] 111 - Housing;

[0050] 112 - Rear lens group;

[0051] 1121 - Rear lens element;

[0052] 1122 - Rear lens barrel;

[0053] 11221 - Mounting part;

[0054] 120 - Lighting unit;

[0055] 121 - Lighting housing;

[0056] 130 - Thermal balance unit;

[0057] 131 - First elastic member;

[0058] 1311 - First heat conducting part;

[0059] 1312 - Second heat conducting part;

[0060] 1313 - Telescopic part;

[0061] 132 - Second elastic member;

[0062] 133 - Heat conducting ring;

[0063] 134 - Snap ring. Detailed implementation manners

[0064] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without any creative work belong to the scope of protection of the present invention. All other embodiments obtained belong to the scope of protection of the present invention. Without conflict, the following embodiments and the features in the embodiments may be combined with each other.

[0065] In the present invention, unless otherwise clearly specified and defined, terms such as "installed", "connected", "coupled", "fixed", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two components or the interaction relationship between two components, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0066] In the present invention, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over", and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath", and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0067] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0068] Figure 1 It is a cross-sectional view of a lens unit in a projection device provided by the prior art. Figure 2A cross-sectional view of a projection device provided by the prior art. Currently, projection devices generally include a lens unit and an illumination unit. In the illumination unit, devices such as the illumination optical path can provide light as a light source. In the lens unit, through refraction between different lenses, the outgoing light can be focused on the projection screen, thereby displaying a normal image. Considering the requirement of low cost, generally, the lens barrel is made of plastic material. Since the thermal conductivity coefficient of plastic is much lower than that of a metal lens barrel, the temperature of the entire rear group lens barrel and the internal lenses increases. However, in existing projection devices, as the temperature rises, the distance between the last lens of the rear group and the flange surface increases or decreases (shown as L1 in the figure), and when adapting to the original illumination system, the back focus will decrease or increase (shown as L2 in the figure), resulting in the occurrence of thermal defocus phenomenon, thereby deteriorating the image resolution.

[0069] In order to overcome the defects in the prior art, the projection device and projection system provided by the present invention, through the setting of the thermal balance unit, can effectively transfer the temperature of the rear group lens barrel to the illumination housing, realizing the temperature balance of the entire system. Through the setting of the added first elastic member, it is ensured that the installation part can always transfer the heat of the rear group to the heat conduction ring through the first elastic member. Among them, the temperature of the rear group is transferred to the end face part of the first elastic member through the installation part, and then the first elastic member transfers the temperature to the heat conduction ring through the other end face. The heat conduction ring is in contact with the illumination housing, so that the heat is fully thermally balanced with the illumination housing, ultimately solving the problem of thermal defocus caused by the too high temperature of the rear group lens group.

[0070] The content of the present invention will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can understand the content of the present invention more clearly and in detail.

[0071] It should be noted that in order to solve the design of different thermal balance schemes for systems on different platforms, and to achieve a stable balance state between the temperature of the rear group lens barrel 1122 and the temperature of the illumination housing 121, so as to keep the back focus within the effective range all the time, the following schemes are designed respectively:

[0072] Scheme 1:

[0073] Figure 3 A structural schematic diagram of the projection device provided by an embodiment of the present application. Figure 4 An exploded view of the first projection device provided by an embodiment of the present application. Figure 5 A partial cross-sectional view of the first projection device provided by an embodiment of the present application in an exploded state. Figure 6 A partial cross-sectional view of the first projection device provided by an embodiment of the present application. Figure 7 A structural schematic diagram of the first elastic member in the first projection device provided by an embodiment of the present application. Figure 8 A partial structural schematic diagram of the first elastic member in the first projection device provided by an embodiment of the present application.

[0074] As Figures 3 to 8 shown, an embodiment of the present application provides a projection device 100, including:

[0075] A lens unit 110, the lens unit 110 includes a housing 111 and a lens group disposed in the housing 111. The lens group includes a rear group lens group 112. The rear group lens group 112 includes rear group lens elements 1121 and a rear group lens barrel 1122. The rear group lens elements 1121 are installed in the rear group lens barrel 1122, and the rear group lens barrel 1122 has a mounting portion 11221 adapted to the housing 111;

[0076] A lighting unit 120, the lighting unit 120 includes a lighting housing 121;

[0077] A thermal balance unit 130, the thermal balance unit 130 is located between the lighting housing 121 and the rear group lens barrel 1122. The thermal balance unit 130 includes a first elastic member 131 and a heat conducting ring 133. Both the first elastic member 131 and the heat conducting ring 133 are sleeved on the rear group lens barrel 1122. The inner edge of the heat conducting ring 133 is sleeved with the side wall of the rear group lens barrel 1122, and the heat conducting ring 133 has a first side wall facing the lighting housing 121 and a second side wall facing away from the lighting housing 121. The first side wall is in thermal contact with the lighting housing 121; the first elastic member 131 abuts between the end face of the mounting portion 11221 and the second side wall. The first elastic member 131 is telescopic in the light incident direction to conduct heat between the mounting portion 11221 and the lighting housing 121.

[0078] Through the above arrangement, that is, through the arrangement of the thermal balance unit 130, the temperature of the rear group lens barrel 1122 can be effectively transferred to the lighting housing 121 to achieve temperature balance of the entire system. Through the arrangement of the added first elastic member 131, it is ensured that the mounting portion 11221 can always transfer the heat of the rear group to the heat conducting ring 133 through the first elastic member 131. Among them, the temperature of the rear group is transferred to the end face part of the first elastic member 131 through the mounting portion 11221, and then the first elastic member 131 transfers the temperature to the heat conducting ring 133 through the other end face. The heat conducting ring 133 is in contact with the lighting housing 121, so that the heat is fully thermally balanced with the lighting housing 121, and finally the problem of thermal defocus caused by the too high temperature of the rear group lens group 112 is solved.

[0079] The following will detail the structures of each part of the projection device 100:

[0080] Due to the need of optical design, the lens elements in the lens unit 110 are usually divided into multiple groups. For example, the lens elements can be divided into a front group and a rear group, or divided into a front group, a middle group and a rear group, etc. Each group usually includes multiple lenses, such as spherical or aspherical lenses.

[0081] The lens group may include a rear lens group 112 and a front lens group. The front lens group is outside the housing 111 of the projection device 100, and the rear lens group 112 is disposed at the end of the front lens group.

[0082] It should be noted that the housing 111 is used to mount the lens group, and the accommodation space of the housing 111 is slightly larger than the external dimensions of the lens group.

[0083] In some examples, the housing 111 may be a metal part, and its material may include one or more of copper, iron, aluminum, tin, and lead.

[0084] In other examples, the housing 111 may be made of plastic.

[0085] It should be noted that the specific material of the housing 111 is not overly limited in the embodiments of the present application.

[0086] Of course, during production and manufacturing, on the premise of ensuring strength, the housing 111 can also be made of steel plates, plastics, or composite materials.

[0087] Correspondingly, the rear lens barrel 1122 is used to mount and accommodate the rear lens group 1121. When the rear lens group 1121 is installed into the rear lens barrel 1122, they form an integral body and are then installed into the housing 111.

[0088] In some examples, the rear lens barrel 1122 and the lighting housing 121 may have the same material as the housing 111 or may be different. Specifically, it can be adjusted according to the actual situation.

[0089] In some examples, the rear lens barrel 1122 and the lighting housing 121 may be metal parts, and their materials may include one or more of copper, iron, aluminum, tin, and lead.

[0090] In other examples, the rear lens barrel 1122 and the lighting housing 121 may be made of plastic.

[0091] Of course, during production and manufacturing, on the premise of ensuring strength, the rear lens barrel 1122 and the lighting housing 121 can also be made of steel plates, plastics, or composite materials.

[0092] It should be noted that the projection device 100 can generally be a laser TV, a projector or other device capable of image projection. In order to realize the projection of the picture, the projection device 100 also includes an optical unit, which includes a digital micromirror device (DMD) and a lighting light path in the front lighting unit 120. The lighting light path can be used as a light source to provide light; and the digital micromirror device is full of micro light valves or light path switches, so it can be used to open and close the light path, so that the light emitted by the lighting light path is selectively passed, thereby forming an image.

[0093] In order to perform operations such as focusing and zooming on the light emitted from the optical unit so that a normal display image is projected on the projection screen, the projection device 100 further includes a lens unit 110. The lens unit 110 includes multiple groups of lenses, each of which includes one or more lenses, so that the light emitted from the optical unit can be focused on the projection screen through refraction between different lenses, thereby displaying a normal image. In order to fix the lenses, the lens unit 110 further includes at least two lens barrels, so that multiple lenses can be fixed in each lens barrel at a preset interval, so as to realize imaging through the refraction of light by the lenses.

[0094] It should be noted that, since the rear group lens barrel 1122 usually partially extends into the interior of the lighting unit 120, the outer wall of the rear group lens barrel 1122 that extends into the interior of the lighting unit 120 can be connected to the thermal balance unit 130, and the thermal balance unit 130 is further connected to the lighting housing 121 of the lighting unit 120. In this way, the heat of the lighting housing 121 can be transferred to the rear group lens barrel 1122 through the thermal balance unit 130, or the heat of the rear group lens barrel 1122 can be transferred to the lighting housing 121 through the thermal balance unit 130, thereby achieving temperature balance of the entire system.

[0095] Specifically, the front lens group is usually located at the front end of the lens group, that is, far away from the lighting unit 120, and the rear lens group 112 is located at the rear end of the lens group, that is, close to one end of the lighting unit 120. The front lens group and the rear lens group 112 can move forward and backward along the axis of the lens group, that is, the optical axis direction, to change the relative distance between the lenses in the front lens group and the lenses in the rear lens group 112, thereby completing the focusing function.

[0096] Among them, since the rear lens group 112 is arranged close to the lighting unit 120, on the one hand, the lenses in the rear lens group 112 are greatly affected by light and heat up quickly; on the other hand, the rear lens group 112 is close to the lighting unit 120, and at least part of it is shielded by the lighting unit 120, and its own heat is difficult to dissipate. Therefore, by connecting the heat balance unit 130 and the rear lens group 112, the heat between the lighting housing 121 and the rear lens barrel 1122 can be balanced, avoiding heat accumulation and ensuring the normal imaging of the lens.

[0097] It should be noted that the lighting housing 121 can transfer heat to the first side wall of the heat conducting ring 133 through the heat conducting ring 133, and the first side wall of the heat conducting ring 133 transfers the heat to the second side wall of the heat conducting ring 133. Then, through the first elastic member 131, the heat can be transferred to the mounting portion 11221; correspondingly, the heat of the rear lens barrel 1122 can be transferred to the first elastic member 131, and the heat can be transferred to the second side wall of the heat conducting ring 133 through the first elastic member 131. The second side wall of the heat conducting ring 133 transfers the heat to the first side wall of the heat conducting ring 133, and then the heat can be transferred to the lighting housing 121 to balance the heat between the lighting housing 121 and the rear lens barrel 1122.

[0098] As Figures 4 to 8 shown, in some alternative embodiments, the distance between the end face of the mounting portion 11221 and the end face of the lighting housing 121 is ≤ 1 mm. For details, please refer to Figure 6 , where A represents the dimension between the end face of the mounting portion 11221 and the end face of the lighting housing 121 in this solution.

[0099] The thickness range of the first elastic member 131 is 0.05 mm - 0.1 mm.

[0100] It should be noted that the setting of the distance between the end face of the mounting portion 11221 and the end face of the lighting housing 121 can meet the requirements of the small size of the projection device 100. Furthermore, in the case of a small size, through the setting of the first elastic member 131, better heat balance can be achieved.

[0101] In addition, it should be noted that the material of the first elastic member 131 can be selected as metal for easy heat conduction. In some examples, the material of the first elastic member 131 is copper.

[0102] In some embodiments, the design of the thickness range of the first elastic member 131 can meet the heat transfer between the rear lens barrel 1122 and the heat conducting ring 133 while meeting the requirement of not transferring torque to the mounting portion 11221.

[0103] As Figures 4 to 8As shown, in some alternative embodiments, the first elastic member 131 includes a first heat-conducting portion 1311 and a second heat-conducting portion 1312. The first heat-conducting portion 1311 abuts against the end face of the mounting portion 11221, and the second heat-conducting portion 1312 abuts against the second side wall. The first elastic member 131 is used to transfer heat between the rear group lens barrel 1122 and the heat-conducting ring 133.

[0104] It should be noted that the inner edge of the heat-conducting ring 133 can be dimensionally matched with the side wall of the rear group lens barrel 1122, so that the inner edge of the heat-conducting ring 133 will fit against the side wall of the rear group lens barrel 1122. Therefore, good contact can be achieved between the side wall of the rear group lens barrel 1122 and the heat-conducting ring 133, enabling the heat on the rear group lens barrel 1122 to be efficiently transferred to the heat-conducting ring 133.

[0105] Secondly, due to tolerance issues, there is a gap between the mounting portion 11221 on the side wall of the rear group lens barrel 1122 and the heat-conducting ring 133. To ensure the heat transfer effect, the first elastic member 131 is located in this gap. The first heat-conducting portion 1311 and the second heat-conducting portion 1312 are respectively located on opposite sides of the first elastic member 131. The first heat-conducting portion 1311 abuts against the end face of the mounting portion 11221, and the second heat-conducting portion 1312 abuts against the second side wall, facilitating the transfer of heat on the rear group lens barrel 1122.

[0106] The heat-conducting ring 133 usually extends radially outward, and the outward-extending portion can be connected to the lighting housing 121 of the lighting unit 120 and transfer the heat from the rear group lens barrel 1122 to the lighting housing 121. In this way, the heat-conducting ring 133 serves as a heat transfer medium to achieve the heat transfer process between the rear group lens barrel 1122 and the lighting housing 121, effectively dissipating the heat of the rear group lens barrel 1122.

[0107] It should be noted that the heat-conducting area of the first heat-conducting portion 1311 can be smaller than that of the second heat-conducting portion 1312. The temperature of the rear group is transferred to the small heat-conducting end face presented by the first heat-conducting portion 1311 of the first elastic member 131 through the mounting portion 11221. Then, the first elastic member 131 transfers the temperature to the heat-conducting ring 133 through the large heat-conducting end face presented by the second heat-conducting portion 1312. The heat-conducting ring 133 is in contact with the lighting housing 121, so that the heat is fully thermally balanced with the lighting housing 121.

[0108] Of course, the heat conduction area of the first heat conduction part 1311 can be larger than that of the second heat conduction part 1312. The temperature of the rear group is transmitted to the large heat conduction end face presented by the first heat conduction part 1311 of the first elastic part 131 through the installation part 11221. Then, the first elastic part 131 transmits the temperature to the heat conduction ring 133 through the small heat conduction end face presented by the second heat conduction part 1312. The heat conduction ring 133 is in contact with the lighting housing 121, so that heat and the lighting housing 121 are fully thermally balanced.

[0109] Correspondingly, the heat conduction area of the first heat conduction part 1311 can be equal to that of the second heat conduction part 1312. The specific size of the heat conduction area and the specific dimensions can be adjusted according to the actual situation and will not be limited too much here.

[0110] In some alternative embodiments, the first elastic part 131 further includes a telescopic part 1313. The telescopic part 1313 is located between the first heat conduction part 1311 and the second heat conduction part 1312, and the opposite ends of the telescopic part 1313 are respectively connected to the first heat conduction part 1311 and the second heat conduction part 1312.

[0111] It should be noted that the design of the telescopic part 1313 facilitates the better close contact of the first heat conduction part 1311 of the first elastic part 131 with the end face of the installation part 11221, and the better close contact of the second heat conduction part 1312 with the second side wall of the heat conduction ring 133, so as to better transfer the heat between the installation part 11221 and the heat conduction ring 133.

[0112] In some alternative embodiments, the first heat conduction part 1311, the telescopic part 1313 and the second heat conduction part 1312 are integrally formed, which can ensure that the first heat conduction part 1311, the telescopic part 1313 and the second heat conduction part 1312 are integrally formed and manufactured and are inseparable from each other. On the one hand, it can reduce the number of parts used, lower the assembly difficulty and the requirements for assembly accuracy, eliminate the welding connection process of the first heat conduction part 1311, the telescopic part 1313 and the second heat conduction part 1312, and improve the assembly efficiency; on the other hand, it can improve the overall stiffness of the first elastic part 131, reduce the possibility of loosening between the first heat conduction part 1311, the telescopic part 1313 and the second heat conduction part 1312, and has relatively high structural strength.

[0113] It should be noted that, in some embodiments, the first heat-conducting part 1311, the telescopic part 1313 and the second heat-conducting part 1312 are connected by an integrated connection method. In other embodiments, the first heat-conducting part 1311, the telescopic part 1313 and the second heat-conducting part 1312 can also be connected by other connection methods. As long as the connection method can fix the first heat-conducting part 1311, the telescopic part 1313 and the second heat-conducting part 1312, the purpose of this embodiment can be achieved. Here, the connection method of the first heat-conducting part 1311, the telescopic part 1313 and the second heat-conducting part 1312 is not limited.

[0114] In some optional embodiments, the cross-section of the first elastic member 131 is annular, and when the second side wall of the heat conductive ring 133 and the end surface of the mounting portion 11221 are pressed against each other, the first elastic member 131 is deformed.

[0115] It should be noted that the first elastic member 131 can be an integral member with a circular cross-section, which is convenient for being sleeved on the side wall of the rear group lens barrel 1122. The first elastic member 131 is a metal plate-like body, which can undergo a certain elastic deformation when subjected to force.

[0116] Through the deformation of the first elastic member 131 , the rear lens barrel 1122 , the first elastic member 131 , the heat-conducting ring 133 and the lighting housing 121 are effectively in contact with each other, thereby ensuring a thermal balance effect.

[0117] like Figures 4 to 8 As shown, in some optional embodiments, the heat balance unit 130 further includes a second elastic member 132, which is disposed on the flange surface of the housing 111 and faces the first elastic member 131, and the first elastic member 131 is located between the second elastic member 132 and the heat conductive ring 133;

[0118] The second elastic member 132 has elastic force along the incident direction of the light, and is used to press the heat-conducting ring 133 abutting against the end surface of the lighting housing 121 .

[0119] It should be noted that the second elastic member 132 is arranged on the flange surface of the shell 111 and has elastic force along the incident direction of the light. Part of the second elastic member 132 is exposed on the outside of the flange surface of the shell 111 along the incident direction of the light, and abuts against the first elastic member 131, thereby pressing the heat-conducting ring 133 abutting against the end face of the lighting shell 121, so that the first side wall of the heat-conducting ring 133 is completely tightly attached to the lighting shell 121 to fully conduct heat.

[0120] In some embodiments, the second elastic member 132 is bent and installed on the flange surface of the shell 111 , that is, along the incident direction of the light, part of the second elastic member 132 is located inside the shell 111 , and another part of the second elastic member 132 is located outside the shell 111 .

[0121] In some optional embodiments, the second elastic member 132 is an annular member, and the second elastic member 132 has a bending portion, which is formed around the center of the second elastic member 132, and the distances between each part of the bending portion and the wall of the heat conductive ring 133 are different.

[0122] It should be noted that such a configuration can enable the bent portion of the second elastic member 132 to better squeeze the first side wall of the heat-conducting ring 133 , so that the second side wall of the heat-conducting ring 133 is completely in close contact with the lighting housing 121 for sufficient heat conduction.

[0123] like Figures 4 to 8 As shown, in some optional embodiments, the thermal balance unit 130 further includes a clamping spring 134, and a clamping slot is provided on the rear group lens barrel 1122, and the clamping spring 134 is clamped in the clamping slot;

[0124] Along the radial direction of the rear lens group barrel 1122 , at least a portion of the clamping spring 134 protrudes from the clamping slot and is used to fix the heat conducting ring 133 .

[0125] It should be noted that the arrangement of the retaining spring 134 can better fix the heat-conducting ring 133 to ensure the stability of the heat-conducting ring 133 being sleeved on the side wall of the rear lens group barrel 1122 .

[0126] In some embodiments, the snap spring 134 is in the shape of a thin sheet and may be in the shape of a semi-ring.

[0127] Option 2:

[0128] Figure 9 An exploded view of a second projection device provided in an embodiment of the present application, Figure 10 A partial cross-sectional view of the second projection device in an exploded state provided in an embodiment of the present application, Figure 11 A partial cross-sectional view of a second projection device provided in an embodiment of the present application.

[0129] It should be noted that if Figures 9 to 11 As shown, when the temperature of the rear mirror group 112 is high, and there is insufficient gap between the rear mirror group 112 and the lighting housing 121, and the rear mirror group 112 cannot be glued, Scheme 1 and Scheme 2 can be adopted, among which Scheme 1 is the specific scheme mentioned above and will not be described in detail here.

[0130] Solution 2 uses the inner circumferential direction for heat conduction contact. Considering the insufficient space for contacting the heat conduction position and the small volume of the heat conduction ring 133, the heat conduction effect of Solution 1 is better than that of Solution 2.

[0131] The reasons are as follows: In Solution 1, the setting of the first elastic member 131 is added to ensure that the installation part 11221 can always transfer the heat of the rear group to the heat conduction ring 133 through the first elastic member 131. The temperature of the rear group is transferred to the end face part of the first elastic member 131 through the installation part 11221, and then the first elastic member 131 transfers the temperature to the heat conduction ring 133 through the other end face. The heat conduction ring 133 contacts the lighting housing 121, so that the heat and the lighting housing 121 are fully thermally balanced, finally solving the problem of thermal defocus caused by the too high temperature of the rear group lens unit 112.

[0132] Therefore, when the temperature of the rear group lens unit 112 is relatively high, the gap between the rear group lens unit 112 and the lighting housing 121 is insufficient, and the rear group lens unit 112 cannot reduce the glue, the heat conduction effect of Solution 1 is better than that of Solution 2.

[0133] Figure 12 It is an exploded view of the third projection device provided by the embodiment of the present application. Figure 13 It is a partial sectional view of the third projection device in an exploded state provided by the embodiment of the present application. Figure 14 It is a partial sectional view of the third projection device provided by the embodiment of the present application.

[0134] When the temperature of the rear group lens unit 112 is relatively high and the gap between the rear group lens unit 112 and the lighting housing 121 is sufficient, for Solution 3, as Figures 12 to 14 shown, when the temperature of the rear group lens unit 112 is relatively high, the gap between the rear group lens unit 112 and the lighting housing 121 is sufficient and the rear group lens unit 112 can perform glue reduction and avoidance, Solution 3 can be adopted. Among them, Figure 14 in, B represents the distance between the end face of the installation part 11221 in Solution 3 and the end face of the lighting housing 121.

[0135] Figure 15 It is a partial sectional view of the fourth projection device in an exploded state provided by the embodiment of the present application. Figure 16 It is a partial sectional view of the fourth projection device provided by the embodiment of the present application.

[0136] For Solution 4, as Figure 15 and Figure 16 shown, when the position of the rear group lens unit 112 cannot perform glue reduction and avoidance or the defocus amount is not large, Solution 4 can be adopted. Among them, Figure 16 in, B represents the distance between the end face of the installation part 11221 in Solution 4 and the end face of the lighting housing 121. The distance between the end face of the installation part 11221 in Solution 3 and the end face of the lighting housing 121 is the same as that in Solution 4.

[0137] Therefore, when the temperature of the rear lens group 112 is relatively high, there is enough clearance between the rear lens group 112 and the lighting housing 121, and the rear lens group 112 can be reduced in size to avoid the gap, the advantage of Scheme 4 over Scheme 3 is that the heat-conducting contact position is closer to the rear lens group assembly support surface and the relatively sensitive position, which can more effectively solve the problem of large lens focus deviation.

[0138] The projection device provided in the embodiment of the present application includes: a lens unit, the lens unit includes a shell and a lens group arranged in the shell, the lens group includes a rear group lens group, the rear group lens group includes a rear group lens and a rear group lens barrel, the rear group lens is installed in the rear group lens barrel, and the rear group lens barrel has a mounting portion adapted to the shell; an illumination unit, the illumination unit includes an illumination shell; a thermal balance unit, the thermal balance unit is located between the illumination shell and the rear group lens barrel, the thermal balance unit includes a first elastic member and a heat-conducting ring, the first elastic member and the heat-conducting ring are both sleeved on the rear group lens barrel, the inner edge of the heat-conducting ring is sleeved with the side wall of the rear group lens barrel, and the heat-conducting ring has a first side wall facing the illumination shell and a second side wall away from the illumination shell, the first side wall and the illumination shell are in abutment with each other for heat conduction; the first elastic member is in abutment between the end face of the mounting portion and the second side wall, and the first elastic member is retractable in the incident direction of light to establish a heat-conducting connection between the mounting portion and the illumination shell.

[0139] By setting the heat balance unit, the temperature of the rear group lens barrel can be effectively transferred to the lighting housing to achieve temperature balance of the entire system. By setting the added first elastic member, it is ensured that the mounting portion can always transfer the heat of the rear group to the heat-conducting ring through the first elastic member, wherein the temperature of the rear group is transferred to the end face of the first elastic member through the mounting portion, and then the first elastic member transfers the temperature to the heat-conducting ring through the other end face. The heat-conducting ring contacts the lighting housing, so that the heat is fully thermally balanced with the lighting housing, and finally the problem of thermal run-of-focus caused by excessive temperature of the rear group lens group is solved.

[0140] In addition, if Figures 4 to 12 As shown, the embodiment of the present application further provides a projection device 100, including:

[0141] The lens unit 110 includes a housing 111, a rear lens group 1121 and a rear lens group barrel 1122 disposed in the housing 111, the rear lens group 1121 is installed in the rear lens group barrel 1122, and the rear lens group barrel 1122 has a mounting portion 11221 adapted to the housing 111;

[0142] The lighting unit 120 includes a lighting housing 121;

[0143] The thermal balance unit 130 is located between the end face of the lighting housing 121 and the rear group lens barrel 1122. The thermal balance unit 130 includes a first elastic member 131 and a heat conducting ring 133. The first elastic member 131 abuts between the end face of the mounting portion 11221 and the wall surface of the heat conducting ring 133. The inner edge of the heat conducting ring 133 is sleeved with the side wall of the rear group lens barrel 1122, and is used for transferring the heat between the rear group lens barrel 1122 and the lighting housing 121.

[0144] The projection device 100 provided by the embodiment of the present application can effectively transfer the temperature of the rear group lens barrel to the lighting housing, realize the temperature balance of the entire system, and finally solve the problem of thermal defocus caused by the too high temperature of the rear group lens group.

[0145] In addition, the embodiment of the present application also provides a projection system, including a projection screen and the above-mentioned projection device 100. The projection device 100 is used for projecting a projection image onto the projection screen.

[0146] The projection screen includes a display film, and the front surface of the display film is the projection light receiving surface.

[0147] It should be noted that the display film usually can be composed of a hard layer, a Fresnel structure layer, a projection layer, etc., has a certain strength and stiffness, and can have a certain perpendicularity in the vertical free hanging state so that the display film looks flat. However, due to still having a certain softness, without support or being interfered by external forces, the display film still cannot meet the flatness requirements for display. If the screen is not flat, it will cause deformation, blurring, uneven brightness, or other deterioration problems when the laser projection image is displayed.

[0148] In order to flatten the display film, in some alternative embodiments, the display film includes a film body and a connecting cloth that are adhered to each other.

[0149] Generally, the film body is made of a hard and straight material, and the connecting cloth generally has characteristics such as non-elastic, ultra-thin, dense, and high strength. When the connecting cloth and the film body are adhered, an integral structure can be formed between the two, so as to facilitate the transmission of force and enable the film body to be stretched following the deformation of the connecting cloth.

[0150] Specifically, the connecting cloth can generally be a soft cloth. In this way, the connecting cloth can better transmit the acting force when being stretched, and has relatively stable properties and can adapt to a relatively wide range of environments.

[0151] In the projection system of this embodiment, the projection device 100 can be various existing projectors, such as laser projectors. The projection device 100 can project a projection image onto the display film of the projection screen, so that the display film can display the projection image for people to watch. Among them, the specific structure, working principle, and functions of the projection device 100 have been described in detail in the foregoing Embodiment 1, and will not be elaborated here.

[0152] Through the setting of the thermal balance unit, the temperature of the rear group lens barrel can be effectively transferred to the illumination housing to achieve the temperature balance of the entire system. Through the setting of the added first elastic member, it is ensured that the installation part can always transfer the heat of the rear group to the heat conduction ring through the first elastic member. Among them, the temperature of the rear group is transferred to the end face part of the first elastic member through the installation part, and then the first elastic member transfers the temperature to the heat conduction ring through the other end face. The heat conduction ring is in contact with the illumination housing, so that the heat can be fully thermally balanced with the illumination housing, finally solving the problem of thermal defocus caused by the too high temperature of the rear group lens group.

[0153] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0154] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, "a plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0155] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A projection device, characterized in that, it includes: a lens unit, the lens unit includes a housing and a lens group disposed in the housing, the lens group includes a rear lens group, the rear lens group includes rear lens elements and a rear lens barrel, the rear lens elements are installed in the rear lens barrel, and the rear lens barrel has a mounting portion adapted to the housing; a lighting unit, the lighting unit includes a lighting housing; a thermal balance unit, the thermal balance unit is located between the lighting housing and the rear lens barrel, the thermal balance unit includes a first elastic member and a heat conducting ring, both the first elastic member and the heat conducting ring are sleeved on the rear lens barrel, the inner edge of the heat conducting ring is sleeved with the side wall of the rear lens barrel, and the heat conducting ring has a first side wall facing the lighting housing and a second side wall facing away from the lighting housing, the first side wall is in thermal contact with the lighting housing; the first elastic member is abutted between the end face of the mounting portion and the second side wall, and the first elastic member is telescopic in the light incident direction to conduct heat between the mounting portion and the lighting housing.

2. The projection device according to claim 1, characterized in that, the distance between the end face of the mounting portion and the end face of the lighting housing ≤ 1 mm; the thickness range of the first elastic member is 0.05 mm - 0.1 mm.

3. The projection device according to claim 1, characterized in that, the first elastic member includes a first heat conducting portion and a second heat conducting portion, the first heat conducting portion abuts against the end face of the mounting portion, the second heat conducting portion abuts against the second side wall, and the first elastic member is used to transfer heat between the rear lens barrel and the heat conducting ring.

4. The projection device according to claim 3, characterized in that, the first elastic member further includes a telescopic portion, the telescopic portion is located between the first heat conducting portion and the second heat conducting portion, and the opposite ends of the telescopic portion are respectively connected to the first heat conducting portion and the second heat conducting portion.

5. The projection device according to any one of claims 1 - 4, characterized in that, the cross section of the first elastic member is circular ring-shaped, and when the second side wall of the heat conducting ring and the end face of the mounting portion are mutually extruded, the first elastic member deforms.

6. The projection device according to any one of claims 1 - 4, characterized in that, the thermal balance unit further includes a second elastic member, the second elastic member is disposed on the flange surface of the housing and faces the first elastic member, and the first elastic member is located between the second elastic member and the heat conducting ring; the second elastic member has an elastic force along the light incident direction and is used to tightly abut against the heat conducting ring on the end face of the lighting housing.

7. The projection device according to claim 6, characterized in that, the second elastic member is a ring-shaped member, the second elastic member has a bent portion, the bent portion is formed by surrounding around the center of the second elastic member, and the distances between the respective parts of the bent portion and the wall surface of the heat conducting ring are different.

8. The projection device according to any one of claims 1 - 4, characterized in that, The thermal balance unit further includes a circlip, a clamping groove is provided on the rear group lens barrel, and the circlip is clamped in the clamping groove; Along the radial direction of the rear group lens barrel, at least part of the circlip protrudes from the notch of the clamping groove and is used to fix the heat conduction ring.

9. A projection device, characterized in that, it includes: a lens unit, the lens unit includes a housing, rear group lenses and a rear group lens barrel arranged in the housing, the rear group lenses are installed in the rear group lens barrel, and the rear group lens barrel has a mounting portion adapted to the housing; a lighting unit, the lighting unit includes a lighting housing; a thermal balance unit, the thermal balance unit is located between the end face of the lighting housing and the rear group lens barrel, the thermal balance unit includes a first elastic member and a heat conduction ring, the first elastic member abuts between the end face of the mounting portion and the wall surface of the heat conduction ring, and the inner edge of the heat conduction ring is sleeved with the side wall of the rear group lens barrel for transferring heat between the rear group lens barrel and the lighting housing.

10. A projection system, characterized in that, it includes a projection screen and the projection device according to any one of claims 1-9, and the projection device is used to project a projection image onto the projection screen.

Images