JP6418916B2 - Rear projection image display device - Google Patents

Description

  The present invention relates to a rear projection video display device, and more particularly to a transmission screen holding structure of a multi-vision rear projection video display device in which a plurality of rear projection video display devices are arranged to form a large screen. .

  In recent years, large screen displays have attracted attention for various monitoring system applications or shopping mall signage applications. As a method for constructing a large screen, multi-vision in which a plurality of rear projection video display devices, liquid crystal display devices, or the like are combined vertically and horizontally is common. A rear projection type video display device is a device that generally projects video light from a projection device from the back of a transmissive screen and displays an image on the transmissive screen.

  As a conventional rear projection image display device for multivision, for example, there is a device disclosed in Patent Document 1. A rear projection image display device described in Patent Document 1 includes a transmission screen configured by superimposing two sheet-like members having transparency, and a support member that supports a rear edge of the transmission screen. And a projection unit that projects an image toward the back of the transmissive screen. The two sheet-like members constituting the transmissive screen are connected to each other by attaching an adhesive sheet to the entire side surface of the two sheet-like members of the transmissive screen.

  Here, the two sheet-like members constituting the transmissive screen are a Fresnel lens that converts light from the light source into substantially parallel light, and a lenticular lens for the purpose of securing a viewing angle by image formation and diffusion. The second adhesive tape is attached to the entire circumference over the side surface of the transmission screen connected by the first adhesive tape and a part of the side surface of the screen support member.

  In a large-screen monitoring system using multivision, multiple rear-projection image display devices are connected in the vertical and horizontal directions to display a large screen image, but the joint width between the screen screens, that is, the image is not displayed. It is necessary to make the region as small as possible, and in the screen holding structure in each rear projection type image display device, a structure having high holding strength while reducing the joint width is required.

  In the rear projection type image display device described in Patent Document 1, in order to reduce the joint width, a screen support member having a light shielding function is provided so as to protrude forward from the screen support frame, and a resin-made Fresnel lens. A notch-shaped portion is formed on the outer peripheral end surface of the screen so as to be flush with the tip of the screen support member. In a state where the cut-out shape portion of the Fresnel lens and the tip portion of the screen support member are fitted, the screen support member is integrally fixed to the screen support member with an adhesive tape together with the lenticular lens.

  Further, in the rear projection type image display device described in Patent Document 2, the first adhesive sheet is disposed so as to extend over the entire side surfaces of the Fresnel lens and the lenticular lens, and the Fresnel lens and the lenticular lens are further formed thereon. A second pressure-sensitive adhesive sheet is disposed across the side surface and part of the side surface of the screen support member so as to extend over the entire circumference. That is, the lenticular lens is fixed to the Fresnel lens and the screen support member with two types of adhesive sheets. The integrated Fresnel lens and lenticular lens are further held on the screen support member by a biasing fitting, and the screen support member is attached to a metal screen support frame. As a result, the transmission type screen composed of the Fresnel lens and the lenticular lens is integrally held, and a narrow joint width is realized at low cost while ensuring the holding strength.

  Further, in the rear projection type image display device described in Patent Document 3, a member having a T-shaped cross section is inserted between each end surface of the lenticular lens and the Fresnel lens, thereby bonding with higher adhesive strength than the adhesive tape. The agent is fixed.

JP 2006-98535 A JP 2006-259229 A JP 2007-127950 A

  In the rear projection type image display device described in Patent Document 1, the Fresnel lens and the lenticular lens are fixed to the screen support member by the same adhesive tape on the outer peripheral end surface. Therefore, when the Fresnel lens and lenticular lens expand or contract due to environmental changes such as temperature or humidity during transportation or warehouse storage, stress concentrates on the outer periphery of the lenticular lens and the lenticular lens, and adhesion There is a problem that a warp change appears in each central part that is not performed, and problems such as separation occur.

  Although the Fresnel lens and lenticular lens are held on the same side with the same adhesive tape, the side surface has a very small area. Therefore, the Fresnel lens and the lenticular lens adhere to each other due to the difference in expansion or contraction between the Fresnel lens and the lenticular lens. There were problems such as tape floating or peeling. Furthermore, since it is held only by the adhesive force of the adhesive tape, there is a problem that the screen falls due to the weight of the lenticular lens, although it is slight.

  In the rear projection type image display device described in Patent Document 2, the linear expansion coefficient of the resin used for the transmissive screen is usually larger than the linear expansion coefficient of the metal support frame. Therefore, when the transmissive screen warps or changes in dimensions due to environmental changes such as temperature or humidity during transportation or warehouse storage, the transmissive screen and the metal support frame that holds the screen expand. In addition, there is a problem in that warping or separation occurs in the transmission screen due to a difference in shrinkage.

  Although the Fresnel lens and lenticular lens are held on the same side with the same adhesive tape, the side surface has a very small area. Therefore, the Fresnel lens and the lenticular lens adhere to each other due to the difference in expansion or contraction between the Fresnel lens and the lenticular lens. There were problems such as tape floating or peeling.

  In the rear projection type image display device described in Patent Document 3, since a gap is formed between the lenticular lens and the Fresnel lens at the outer peripheral portion, the focus is slightly increased or the image is distorted in the peripheral portion of the transmissive screen. There was a problem of doing.

  Therefore, the present invention suppresses the occurrence of warping, bending, or expansion / contraction from the screen due to environmental changes, stably holding the screen, and preventing the occurrence of image defects on the screen. An object is to provide a video display device.

A rear projection type video display apparatus according to the present invention is a rear projection type video display apparatus that projects an image projected from a projection unit from the rear side of a transmissive screen, the transmissive screen comprising a front side screen sheet and a rear side. A screen holding member that is configured by superimposing a side screen sheet and is fixed to an edge of the back side screen sheet, a screen support frame that supports the transmission screen via the screen holding member, and An adhesive that fixes the edge of the back side screen sheet and the front end surface of the screen holding member is pasted from the side of the back side screen sheet to the front side of the screen holding member. Adhesive tape and from the side surface portion of the front screen sheet to the rear side surface portion of the screen holding member And a adhesive sheet affixed so as to straddle the adhesive tape, the adhesive sheet has a slipping property without being adhered against the adhesive tape, the back side screen sheet said screen held by the adhesive tape The front screen sheet is fixed to the screen holding member by the adhesive sheet straddling the adhesive tape.

According to the present invention, the adhesive sheet is for the adhesive tape has a slipping property without being adhered, the rear side screen sheet is fixed to the screen holding member by an adhesive tape, the front-side screen sheet straddle the adhesive tape bonding It is fixed to the screen holding member by the sheet.

  Therefore, when an environmental change such as temperature or humidity occurs during transportation or warehouse storage, the screen sheet on the back side and the screen sheet on the front side can be expanded and contracted separately. It is suppressed and the occurrence of separation is also suppressed. In addition, in the adhesive tape and adhesive sheet fixing portions to which the respective screen sheets are fixed, the occurrence of the floating and peeling of the adhesive tape and the adhesive sheet can be suppressed.

  As described above, it is possible to stably hold the transmission screen by suppressing warpage, bending, or expansion / contraction of the transmission screen due to the environmental change, and further, the front screen sheet and the rear surface side. Since it is not a structure in which a gap is provided between the screen sheet and the screen, a defective portion of an image is not generated on the transmissive screen.

It is a perspective view which shows schematic structure of the rear projection type video display apparatus which concerns on embodiment. It is a perspective view which shows schematic structure of the multivision which consists of a some rear projection type video display apparatus. FIG. 3 is a cross-sectional view taken along line S1-S1 or S2-S2 of FIG. It is an enlarged view which shows the cross-sectional structure of the transmission type screen holding structure of FIG. FIG. 4 is an enlarged view showing a state in which a lenticular lens is extended due to a temperature change in the cross-sectional configuration of the transmission screen holding structure of FIG.

<Embodiment>
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a schematic configuration of a rear projection type image display apparatus 10 according to the embodiment. As shown in FIG. 1, the rear projection type image display device 10 includes a housing 1, a transmission screen 2, a projection unit 3, a screen holding member 4 and a screen support frame 5, and is projected from the projection unit 3. This is a device for projecting an image to be projected from the back surface of the transmissive screen 2.

  As shown in FIGS. 3 to 5 to be described later, the transmission screen 2 is configured by superposing a lenticular lens 22 (front side screen sheet) and a Fresnel lens 21 (rear side screen sheet). In addition, description of each component of the rear projection type image display apparatus 10 will be described later.

  Next, multivision will be described. FIG. 2 is a perspective view showing a schematic configuration of multivision including a plurality (four) of rear projection image display devices 10. As shown in FIG. 2, the multi-vision is configured by combining two rear projection image display devices 10 in the vertical direction and two in the horizontal direction, for example. A screen interval (hereinafter referred to as “joint width”) WA between two rear projection image display devices 10 arranged in the horizontal direction WA, and between two rear projection image display devices 10 arranged in the vertical direction. In order to make the joint width WB in the vertical direction as small as possible, each casing 1 and each screen support frame 5 has a skeleton formed of a metal frame having a relatively small linear expansion coefficient. Further, each transmissive screen 2 made of resin is manufactured by NC processing to suppress dimensional variations, and has elasticity with respect to the screen holding member 4 that holds each transmissive screen 2. As a result, when the environment changes, the expansion / contraction, warpage, and deflection change of the resin-type transmission screen having a relatively large linear expansion coefficient with respect to the metal screen support frame 5 having a relatively small linear expansion coefficient. It is configured to absorb.

  Although details will be described later with reference to FIG. 4, the rear projection display 10 further includes an adhesive 13, a single-sided adhesive heat-resistant tape 11 (adhesive tape), and a thermal adhesive resin sheet 12 (adhesive sheet), and has a thickness. The joint width is suppressed by holding the Fresnel lens 21 and the lenticular lens 22 constituting the transmission screen 2 with the 80 μm single-sided adhesive heat-resistant tape 11 and the thermoadhesive resin sheet 12 having a thickness of 110 μm.

  Next, the transmission screen holding structure of the rear projection type image display device 10 will be described. 3 is a cross-sectional view taken along line S1-S1 or S2-S2 of FIG. 2, FIG. 4 is an enlarged view showing a cross-sectional configuration of the transmission screen holding structure of FIG. 3, and FIG. FIG. 5 is an enlarged view showing a state in which a lenticular lens 22 is extended due to a temperature change in the cross-sectional configuration of the transmission screen holding structure. 3, 4, and 5, the projection light 300 that is an image projected from the projection unit 3 is illustrated.

  As shown in FIG. 3, the screen holding member 4 is fixed to an edge portion on the back side of the Fresnel lens 21. The screen support frame 5 is a member that supports the transmission screen 2 via the screen holding member 4, and is fixed to the back side of the screen holding member 4 with a fixing member 6 such as a screw.

  As shown in FIGS. 3 and 4, the Fresnel lens 21 is made of an acrylic resin such as polymethyl methacrylate (PMMA) or methyl methacrylate / styrene copolymer (MS). The screen holding member 4 is made of the same type of acrylic resin having a linear expansion coefficient equivalent to that of the Fresnel lens 21.

  The single-sided adhesive heat-resistant tape 11 is formed by applying an acrylic pressure-sensitive adhesive on the adhesive side of a polytetrafluoroethylene (PTFE) resin base material having a heat-resistant temperature of 200 ° C. or higher, High adhesiveness with the Fresnel lens 21 made of acrylic resin is ensured. On the contrary, the non-sticking surface side is characterized by non-adhesiveness (non-adhesiveness) and high slipperiness due to the polytetrafluoroethylene (PTFE) base material.

  The Fresnel lens 21 is firmly fixed at the edge portion by the front end portion (front side front end surface) of the screen holding member 4 and the adhesive 13, and the side surface portion 21 a of the Fresnel lens 21 and the screen are fixed by the single-sided adhesive heat-resistant tape 11. The front side surface portion 4a of the holding member 4 is fixed in an auxiliary manner. Thereby, the Fresnel lens 21 and the screen holding member 4 are more firmly integrated with redundancy. Here, the adhesive 13 is a solvent-type adhesive.

  Like the Fresnel lens 21, the lenticular lens 22 is made of an acrylic resin such as polymethyl methacrylate (PMMA) or methyl methacrylate / styrene copolymer (MS). The thermoadhesive resin sheet 12 is an epoxy resin impregnated thermosetting type adhesive sheet. The thermal adhesive resin sheet 12 includes a front portion and a rear portion, more specifically, a bonding portion 12a provided at a position corresponding to the side surface portion 22a of the lenticular lens 22 and the rear side surface portion 4b of the screen holding member 4. I have.

  At the side surface portion 22 a of the lenticular lens 22, the thermoadhesive resin sheet 12 is firmly bonded, and the thermoadhesive resin sheet 12 is firmly attached to the rear side surface portion 4 b of the screen holding member 4 so as to straddle the single-sided adhesive heat-resistant tape 11. It is glued. Here, the thermal adhesive resin sheet 12 straddles the single-sided adhesive heat-resistant tape 11, but is not bonded to the single-sided adhesive heat-resistant tape 11. The heat-bonding resin sheet 12 is heated and pressed at 120 ° C. to 150 ° C. for a predetermined time by a heater such as an iron, so that both side surfaces 22a of the acrylic lenticular lens 22 and the rear side of the screen holding member 4 are used. The side part 4b is firmly bonded. However, the heat-adhesive resin sheet 12 is not bonded to the single-sided adhesive heat-resistant tape 11 made of polytetrafluoroethylene (PTFE) having high heat resistance, which auxiliaryly fixes the Fresnel lens 21 and the screen holding member 4. To ensure slipperiness.

  In this manner, the side surface portion 21a of the Fresnel lens 21 made of acrylic resin and the side surface portion 22a of the lenticular lens 22 are separately firmly fixed and supported by the screen holding member 4 also made of acrylic resin. ing. As a result, even if an environmental change such as temperature or humidity occurs during transportation or warehouse storage, the Fresnel lens 21 is firmly supported at a position close to the screen holding member 4, but the fixing portion thereof is partially It is difficult to apply excessive stress. In addition, since the expansion and contraction of the Fresnel lens 21 is absorbed by the elastic force of the screen holding member 4, it is possible to suppress changes in warping and bending of the Fresnel lens 21.

  The lenticular lens 22 is firmly fixed and supported by the thermal adhesive resin sheet 12 straddling the rear side surface portion 4b of the screen holding member 4 although it is located away from the screen holding member 4. Therefore, the expansion and contraction of the lenticular lens 22 is absorbed by the elastic force of the heat bonding resin sheet 12, and a partial stress is not easily applied to the fixed portion. For example, as shown in FIG. 5, when the lenticular lens 22 expands due to a temperature change, the force received from the lenticular lens 22 is absorbed by the elastic force of the thermal adhesive resin sheet 12, and a partial stress is applied to the fixing portion. It becomes difficult. In addition, although the side surface portion 21a of the Fresnel lens 21 and the side surface portion 22a of the lenticular lens 22 are adjacent to each other, it is difficult for direct stress to be applied to each other, so that changes in warpage and deflection of the lenticular lens 22 can be suppressed.

  As described above, in the rear projection type image display device 10 according to the embodiment, the thermal adhesive resin sheet 12 is not bonded to the single-sided adhesive heat-resistant tape 11, and the Fresnel lens 21 is attached to the screen holding member 4 by the single-sided adhesive heat-resistant tape 11. The lenticular lens 22 is fixed to the screen holding member 4 by a thermoadhesive resin sheet 12 straddling the single-sided adhesive heat-resistant tape 11.

  Therefore, when an environmental change such as temperature or humidity occurs during transportation or warehouse storage, the Fresnel lens 21 and the lenticular lens 22 can be separately expanded and contracted, so that the Fresnel lens 21 and the lenticular lens 22 are warped and bent. Is suppressed, and the occurrence of separation is also suppressed. Moreover, in the fixing part of the single-sided adhesive heat-resistant tape 11 to which the Fresnel lens 21 is fixed, and the fixing part of the thermoadhesive resin sheet 12 to which the lenticular lens 22 is fixed, the single-sided adhesive heat-resistant tape 11 and the thermoadhesive resin sheet 12 Occurrence of floating and peeling can also be suppressed.

  As described above, the transmissive screen 2 can be stably held by suppressing the warp, bend, or expansion / contraction of the transmissive screen 2 due to environmental changes, and the lenticular lens 22 and Fresnel. Since there is no structure in which a gap is provided between the lens 21 and the transmissive screen 2, an image defect is not generated.

  Further, the conventional rear projection type image display device described in Patent Document 1 has a problem that the machining cost due to NC machining for providing a notch-shaped portion on the outer peripheral end face of the Fresnel lens is high. On the other hand, in the rear projection type image display device 10 according to the embodiment, since it is not necessary to provide a notch-shaped portion on the outer peripheral end surface of the Fresnel lens 21, an increase in machining cost can be suppressed.

  In addition, in the conventional rear projection type image display device described in Patent Document 2, the strength defect is supplemented by adding an urging bracket with a claw for holding the screen to a key point. Since the claw portion of the brace is visible, there is a problem that the claw portion is recognized by the user as a missing portion of the video. Furthermore, in the conventional rear projection type image display device described in Patent Document 2, there is a problem that the surface of the screen is damaged by the contact between the claw portion of the urging bracket and the surface resin sheet of the screen. there were. On the other hand, since the rear projection type image display apparatus 10 according to the embodiment does not use the urging bracket with the claw, these problems do not occur.

  Since the lenticular lens 22, the Fresnel lens 21, the screen holding member 4, the single-sided adhesive heat-resistant tape 11 and the thermal adhesive resin sheet 12 include the same system resin having an equivalent linear expansion coefficient, even when an environmental change occurs, In these fixing portions, partial stress is difficult to be applied, and the expansion, contraction, and deflection of the lenticular lens 22 and the Fresnel lens 21 can be further suppressed.

  The single-sided adhesive heat-resistant tape 11 has heat resistance, and the surface of the single-sided adhesive heat-resistant tape 11 on the side where the thermoadhesive resin sheet 12 straddles has non-adhesiveness and slipperiness, and the thermoadhesive resin sheet 12 is thermosetting adhesive. The side surface portion 22a of the lenticular lens 22 and the rear side surface portion 4b of the screen holding member 4 are bonded by thermosetting.

  Therefore, since the Fresnel lens 21 and the lenticular lens 22 are separately firmly fixed and supported by the thin single-sided adhesive heat-resistant tape 11 and the thermal adhesive resin sheet 12, respectively, the lenticular lens 22 and The Fresnel lens 21 can reduce the influence of a partial stress change caused by expansion, contraction, or deflection change of the other screen sheet in each fixing portion. As a result, it is possible to suppress warping, deflection change, and separation as a whole of the transmissive screen 2, and it is also possible to suppress the occurrence of floating and peeling of the single-sided adhesive heat-resistant tape 11 and the thermoadhesive resin sheet 12.

  In the present invention, the embodiments can be appropriately modified and omitted within the scope of the invention.

  2 transmissive screen, 3 projection unit, 4 screen holding member, 5 screen support frame, 10 rear projection image display device, 11 single-sided adhesive heat-resistant tape, 12 thermal adhesive resin sheet, 13 adhesive, 21 Fresnel lens, 22 lenticular lens.

Claims (4)

A rear projection type image display device for projecting an image projected from a projection unit from the rear side of a transmissive screen,
The transmission screen is configured by superimposing a front screen sheet and a back screen sheet,
A screen holding member fixed to an edge of the back side screen sheet;
A screen support frame that supports the transmission screen via the screen holding member;
An adhesive that fixes the edge of the back side screen sheet and the front end surface of the screen holding member;
An adhesive tape that is pasted from the side surface portion of the back side screen sheet to the front side surface portion of the screen holding member;
An adhesive sheet that is pasted so as to straddle the adhesive tape from the side surface portion of the front screen sheet across the rear side surface portion of the screen holding member;
With
The adhesive sheet has a slipping property without being adhered against the adhesive tape, the back side screen sheet is fixed to the screen holding member by the adhesive tape, the front-side screen sheet straddling the adhesive tape A rear projection type image display device fixed to the screen holding member by the adhesive sheet.   2. The rear projection type image display according to claim 1, wherein the front side screen sheet, the rear side screen sheet, the screen holding member, the adhesive tape, and the adhesive sheet contain the same system of resin having an equivalent linear expansion coefficient. apparatus. The pressure-sensitive adhesive tape has heat resistance, and the surface of the pressure-sensitive adhesive tape on which the adhesive sheet straddles has non-adhesiveness and slipperiness,
2. The rear projection according to claim 1, wherein the adhesive sheet has a thermosetting adhesive layer, and bonds a side surface portion of the front screen sheet and a rear side surface portion of the screen holding member by a thermosetting action. Type image display device. A rear projection type image display device for projecting an image projected from a projection unit from the rear side of a transmissive screen,
The transmission screen is configured by superimposing a front screen sheet and a back screen sheet,
A screen holding member fixed to an edge of the back side screen sheet;
A screen support frame that supports the transmission screen via the screen holding member;
An adhesive that fixes the edge of the back side screen sheet and the front end surface of the screen holding member;
An adhesive tape that is pasted from the side surface portion of the back side screen sheet to the front side surface portion of the screen holding member;
An adhesive sheet that is pasted so as to straddle the adhesive tape from the side surface portion of the front screen sheet across the rear side surface portion of the screen holding member;
With
The adhesive sheet is not adhered to the adhesive tape, the back-side screen sheet is fixed to the screen holding member by the adhesive tape, and the front-side screen sheet is attached to the screen holding member by the adhesive sheet straddling the adhesive tape. Fixed,
The pressure-sensitive adhesive tape has heat resistance, and the surface of the pressure-sensitive adhesive tape on which the adhesive sheet straddles has non-adhesiveness and slipperiness,
The adhesive sheet has a thermosetting adhesive layer, and adheres a side surface portion of the front screen sheet and a rear side surface portion of the screen holding member by a thermosetting action.

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