JP2007041344A - Transmission-type projection screen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixing method for a transmission-type screen, whereby the application of sidewise (horizontal) tension to a lens sheet, that cannot stand by itself, is further ensured, the need for significant changes in housing (frame) and fixing tool used for mounting it onto a display screen is eliminated, the structure is made relatively simple, wrinkles or slacks are made less likely to be caused, and the transmission-type screen can be mounted stably. <P>SOLUTION: In the transmission type projection screen, a short strip of reinforcing member is stuck to the entire upper edge of at least one side of the lenticular sheet. In addition, the lenticular sheet and a Fresnel lens sheet are stuck together with a both-sided adhesive tape applied along the lower edge of the lenticular sheet. This forms a structure, in which tension is applied to the lower part of the lenticular sheet by the weight of the Fresnel lens sheet. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to an improvement in a screen used for a display represented by a transmissive projection TV (transmission TV, rear projection TV, rear projection TV, and the like, although all are synonymous). .
In particular, when one of the screens formed by superposing a Fresnel lens sheet and a lenticular sheet is composed of a flexible base material that is not self-supporting (has flexibility), it is mounted on the display screen. The present invention relates to a method for fixing a screen that can be stably mounted with a relatively simple structure without requiring a significant change in a housing (frame) and a fixing jig used for the purpose.

In a transmission type projection screen in which both the Fresnel lens sheet and the lenticular sheet have a self-supporting structure, both lens sheets are inserted in a concave portion on the inside of the casing and fixed using a jig as a separate member.
Here, being self-supporting means having a rigidity that can be raised while maintaining the shape.
FIG. 1 shows an example of a conventional fixing method. A lenticular sheet 1 and a Fresnel lens sheet 2 are placed in a recess (housing frame) of a housing (frame) 3 and screws 5 are used via a holding member 4. And fix.
In the figure, the left side is the viewer side, and the right side is the TV cabinet side provided with a projector.

  In FIG. 1, there is a relationship between the material of the Fresnel lens sheet 2 and the lenticular sheet 1 and the material of the housing (frame) 3, but the Fresnel lens sheet 2 and the lenticular sheet 1 have large differences in thermal expansion coefficients. If the thickness is the same, the Fresnel lens sheet 2 and the lenticular sheet 1 are overlapped and fixed with an adhesive tape (not shown), and then fixed to the housing (frame) 3 to change the temperature. Even if the Fresnel lens sheet and the lenticular sheet float or warp in accordance with changes in humidity or humidity, they will return to their original state when left in a room temperature environment.

On the other hand, transmissive projection screens using lenticular sheets and Fresnel lens sheets are being made thinner in order to improve optical characteristics.
As for the lenticular sheet, it is necessary to reduce the fine pitch with the higher definition of the image source, and with the fine pitch, the optical characteristics will inevitably become thinner.
As for the Fresnel lens sheet, if the plate thickness is large, a double image is generated due to stray light.
As this thinning progresses, with only the two-lens lens sheet and Fresnel lens sheet configuration, when an external force is applied from the outside of the screen, the screen may be easily detached from the frame due to insufficient rigidity, or the screen may be damaged. Invite problems such as.
Recently, a screen using a Fresnel lens sheet or a lenticular sheet made of a flexible base material having no self-supporting property (having flexibility) has been developed, and when at least one lens sheet has flexibility, When assembling to a TV, in addition to the above, an attachment method (fixing method) that eliminates the following adverse effects is required.

  In a projection screen in which one lens sheet is a non-supporting base material and the other lens sheet is a self-supporting base material, if two or four sides are fixed with adhesive or adhesive, the temperature Due to expansion and contraction due to changes and humidity changes, the lens sheet that is not self-supporting wrinkles and floats, and when incorporated in a transmissive projection TV, the focus blurs and color shifts over time. Therefore, there is a problem that image deterioration is caused.

The following cases are well-known as applications related to the mounting method (fixing method) assuming a screen composed of the above lens sheet combination (when one is not self-supporting and the other is self-supporting). I write.
JP-A-10-246918 Japanese Patent Laid-Open No. 11-271883 JP 2004-94147 A JP 2004-118166 A

<Patent Document 1>
In a transmission screen that combines a Fresnel lens sheet and a lenticular lens sheet,
The lenticular lens sheet is formed on a transparent substrate film with insufficient rigidity, and a lens portion made of a cured product of a photocurable resin or a radiation curable resin is formed.
A screen for image projection, characterized in that a side edge portion of the lenticular lens sheet and a holding frame of the screen are joined and fixed via a synthetic resin film having heat shrinkability. (Claim 1)

<Patent Document 2>
In a transmissive screen composed of a plurality of screens that expands and contracts due to changes in temperature and humidity, on which image light emitted from an image generation source is projected,
A first screen and a second screen having a rigidity relatively lower than that of the first screen, and the second screen in a state of being extended in high temperature and / or high humidity on the first screen. A transmission screen characterized by being fixed. (Claim 1)

<Patent Document 3>
A method of fixing a screen configured by superposing a Fresnel lens and a lenticular lens to a housing frame of a transmissive reaction screen television,
By sticking a single-sided adhesive tape around the superimposed Fresnel lens and lenticular lens in a U shape, the Fresnel lens and lenticular lens are integrated and fixed as a screen,
A method for fixing a screen, wherein the screen is fixed to a housing frame without applying pressure. (Claim 1)

<Patent Document 4>
In a transmissive rear projection screen in which a Fresnel lens sheet and a lenticular lens sheet are overlapped and the periphery is supported and fixed by a housing frame and a holder,
Either the Fresnel lens sheet or the lenticular lens sheet is composed of a lens sheet (2) made of a base material having self-supporting property, and the lens sheet (1) made of a base material having no self-supporting property. The lens sheet (2) made of a base material having no self-supporting property and the lens sheet (1) made of a base material having self-supporting property are fixed with an elastic adhesive layer (31) at a lower edge thereof. The upper edge of the lens sheet (1) made of a non-base material and one end of the holding tape (30) are fixed by the adhesive layer (41), and the other end of the holding tape (30) is the housing. Connected and fixed to the body frame (11a) via the adhesive layer (42) with the holder (12a) and the screw (13),
The lens sheet (2) made of the non-self-supporting base material is suspended between the housing frame (11a) and the holder (12a) and at one end of the lens sheet (2) by the holding tape (3). ) And the holder (12b). A transmissive rear projection screen characterized by being held between the holder and the holder (12b). (Claim 1: see FIG. 2)

  In the method disclosed in Patent Document 2 described above, a lens sheet that is not self-supporting is preliminarily stretched at a high temperature and / or high humidity, and then bonded to the lens sheet having self-supporting characteristics. Since a lens sheet that does not stretch is not self-supporting and is attached to the TV set, tension is always applied in the direction of contraction, so that the lens sheet is kept stretched without wrinkles or sagging. And the process of extending | stretching in high humidity is required.

In the methods disclosed in the above Patent Documents 1, 3, and 4, a self-supporting lens sheet and a non-self-supporting lens sheet are combined with a heat-shrinkable synthetic resin film (Patent Document 1), a single-sided adhesive tape ( Patent Document 3), holding tape (Patent Document 4) and the like are joined via a flexible film-like member, and tension is not sufficiently applied to the lens sheet in the lateral direction (horizontal direction) where gravity does not act. It is.
In other words, when an external force that causes lateral (horizontal) wrinkles or sagging acts on the lens sheet, wrinkles or sagging may occur on the lens sheet including the film-like member to be joined.

  In the present invention, the lateral (horizontal) tension is more reliably applied to the lens sheet that is not self-supporting, and the housing (frame) and fixing jig used for mounting on the display screen can be significantly changed. It is an object of the present invention to propose a method for fixing a screen that can be stably mounted with a relatively simple structure, which is less likely to cause wrinkles and sagging.

In order to achieve the above object, in the transmissive projection screen according to the present invention,
In a transmissive screen that is mounted on the display screen of a transmissive projection display by superposing a Fresnel lens sheet and a lenticular sheet and supporting and fixing the periphery to the frame,
In the lenticular sheet, a lens part composed of a cylindrical lens group is formed on the surface of the translucent substrate film with a cured product of a radiation curable resin, and the entire structure is flexible.
In the Fresnel lens sheet, a lens part is formed of a cured product of a radiation curable resin on the surface of a translucent base film, and a sheet having a light diffusion function is laminated and integrated on the film surface on the side opposite to the lens part. And is not flexible as a whole, and has a configuration with greater rigidity and thickness compared to the lenticular sheet,
On the upper side of the lenticular sheet, at least one side of the lenticular sheet has a strip-shaped reinforcing member attached along the entire upper side,
On the lower side of the lenticular sheet, the lenticular sheet and the Fresnel lens sheet are attached to each other on the surface of the lens part side by a double-sided adhesive tape along the lower side.
On the upper side of the frame, the Fresnel lens sheet and the lenticular sheet are pressed through a holding member so that the lenticular sheet is closely fixed to the upper side of the frame.
At the lower side of the frame, the Fresnel lens sheet suspended from the upper side of the frame and the lower side of the lenticular sheet are pressed through a holding member in a state where they are free ends,
Due to the weight of the Fresnel lens sheet, the lenticular sheet has a structure in which tension is applied downward.

In the transmissive projection screen according to the present invention,
A strip-shaped reinforcing member is attached to at least one side of the lenticular sheet that is not self-supporting (having flexibility), preventing wrinkles and sagging in the horizontal direction (horizontal direction). It is done.
In the vertical direction (vertical direction), it has a structure that is hung with a Fresnel lens sheet that is stiffer and thicker than the lenticular sheet. The weight of the Fresnel lens sheet causes the lenticular sheet to have downward tension. Therefore, wrinkles and sagging in the vertical direction (vertical direction) are also prevented.

Hereinafter, embodiments (examples) of the present invention will be described in detail with reference to the drawings.
<Example 1>
FIG. 3 is an explanatory cross-sectional view illustrating an outline of a screen mounting method (fixing method) according to the first embodiment of the present invention.
In the lenticular sheet, a lens part composed of a cylindrical lens group is formed on the surface of the translucent substrate film with a cured product of a radiation curable resin, and the entire structure is flexible.
In the Fresnel lens sheet, a lens part is formed of a cured product of a radiation curable resin on the surface of a translucent base film, and a sheet having a light diffusion function is laminated and integrated on the film surface on the side opposite to the lens part. In general, the lenticular sheet and the Fresnel lens sheet are simplified and have different thicknesses. It is illustrated as a lens sheet having a layer structure.

As the ratio of the thicknesses of both lens sheets, Fresnel lens sheet (F): lenticular sheet (L) is preferably (F / L) ≧ 1.5, and the greater the difference between the two, the more independent. By using the weight of the lens sheet on the side, the action of applying tension to the lens sheet on the other side (not self-supporting) greatly acts.
The specific gravity of both lens sheets is about (F / L) ≧ 1.5 if there is no significant difference between the materials of both.

On the upper side of the lenticular sheet, a strip-shaped reinforcing member is attached to one side of the lenticular sheet (the right side on the observer side in the figure) along the entire upper side with a double-sided tape.
In the figure, an acrylic plate is used as the reinforcing member. However, the reinforcing member is not limited to this, and the strength (depending on the thickness and rigidity) that prevents wrinkles and sagging from occurring in the flexible lenticular sheet. However, it is preferable that the screen is light in weight because of the screen mounting structure.

At the lower side of the lenticular sheet, the lenticular sheet and the Fresnel lens sheet are attached by a double-sided adhesive tape along the lower side (not shown in detail, but they face each other with the lens side facing each other) Is common),
On the upper side of the frame, the Fresnel lens sheet and the lenticular sheet are pressed through a holding member so that the lenticular sheet is closely fixed to the upper side of the frame.
At the lower side of the frame, the Fresnel lens sheet suspended from the upper side of the frame and the lower side of the lenticular sheet are pressed through a holding member in a state where they are free ends,
Due to the weight of the Fresnel lens sheet, the lenticular sheet has a structure in which tension is applied downward.

It is preferable that the strip-shaped reinforcing member (acrylic plate) whose longitudinal method extends in the paper surface vertical method is stuck in a state where it is in contact with a region having a width of 10 mm or more from the upper edge of the lenticular sheet.
If the contact area of the reinforcing member (acrylic plate) is secured against the flexible lenticular sheet, it is effective in preventing wrinkles and sagging from occurring on the lenticular sheet. With a lenticular sheet equivalent to the screen size of a projection TV (diagonal of 30 inches or more), if there is a contact width of about 20 mm from the upper side, the stability over time (environmental resistance to high temperature / high humidity experiments) is sufficient. It has been confirmed by experiment.

On the upper side of the lenticular sheet, the lenticular sheet and the reinforcing member (acrylic plate) are fixed with a clip so that the cross section becomes a U-shape,
The lower side of the lenticular sheet is also fixed by a clip so that the cross section becomes a U shape.

When fixing a lenticular sheet with a strip-shaped reinforcing member (acrylic plate) adhered to the top side of the frame, it can be joined with a double-sided adhesive tape, fixed with screws or bolts, or suspended from above the frame via an elastic body. Selected from at least one of
In this embodiment, as shown in the drawing, fixing by a bolt penetrating the holding member and the lenticular sheet is employed, and the holding member presses the screen including the Fresnel lens sheet against the frame.

<Example 2>
FIG. 4 is an explanatory cross-sectional view illustrating an outline of a screen mounting method (fixing method) according to the second embodiment of the present invention.
The difference from Example 1 (FIG. 3) is that, when the lenticular sheet with the strip-shaped reinforcing member (acrylic plate) is adhered and fixed to the upper side of the frame, bonding with a double-sided adhesive tape is employed. The bolt that does not penetrate the lenticular sheet fixes the holding member and the upper side of the frame.

  In this example, the direct fixing means for suspending the lenticular sheet from above the frame depends on the adhesive strength of the double-sided adhesive tape, but when considering the decrease in adhesive strength over time, the adhesive is: Since natural rubber has weak adhesive strength, acrylic, silicone and synthetic rubbers are desirable.

In Examples 1 and 2,
In the lenticular sheet, as the translucent substrate film, a material: a PET film having a thickness of 188 μm,
In the Fresnel lens sheet, as the translucent substrate film, a material obtained by dispersing and mixing a diffusing agent: an acrylic plate having a thickness of 2.0 mm was used.
In order to reduce wrinkles and sagging of the lenticular sheet within the flexible range, the thickness of the translucent substrate film is increased, or a material having high rigidity is used, etc. However, as described above, the ratio of the thicknesses of the two is preferably (F / L) ≧ 1.5.

  Further, as shown in Examples 1 and 2, when the lenticular sheet and the reinforcing member (acrylic plate) are fixed with a clip, a protrusion corresponding to the thickness of the clip is provided at a portion where the upper side of the lenticular sheet contacts the upper side of the frame. Therefore, there arises a disadvantage that the reinforcing member and the frame are difficult to contact uniformly over the entire surface.

  Therefore, at the place where the lenticular sheet and the reinforcing member are fixed by the clip, if the concave portion (spot face) corresponding to the thickness of the clip is formed on the surface of the reinforcing member, the reinforcing member and the frame are spread over the entire surface. Contact uniformly.

  Alternatively, the strip-shaped reinforcing member is not attached along the entire upper side on the upper side of the lenticular sheet, and the strip-shaped reinforcing member is intermittently removed except for the portion where the lenticular sheet and the reinforcing member are fixed by the clip. The member may be affixed, and the lenticular sheet and the frame may be affixed with a double-sided adhesive tape on the reinforcing member surface without a clip.

The following are various modifications of the embodiment of the present invention.
Except for the lower frame portion where the screen is mounted, the structure of the upper frame portion will be described with reference to the outline.
In the drawing, description with reference numerals and the like is omitted, but the thick lens sheet on the left side is a Fresnel lens sheet, and the thin lens sheet on the right side is a lenticular sheet.

<Example 3: See FIG. 5>
The lenticular sheet and the reinforcing member are fixed with a double-sided adhesive tape, and they are joined to the upper side of the frame using a double-sided adhesive tape without being fixed with a clip.

<Example 4: See FIG. 6>
The reinforcing member is fixed with a double-sided adhesive tape on the projector-side surface of the lenticular sheet, and the lenticular sheet is suspended from above the frame using an elastic body.
As the elastic body, a coil spring is used as shown, or a rubber material is used.
By adopting the above structure, the lenticular sheet can be tensioned upward, and the tension in the vertical direction of the lenticular sheet is further strengthened together with the downward tension applied by the weight of the Fresnel lens sheet.

<Example 5: See FIG. 7>
The reinforcing member is fixed with double-sided adhesive tape on both the observer side and the projector side of the lenticular sheet, and the reinforcing members on the front and back sides are suspended from above the frame using two elastic bodies.
The reinforcing members on the front and back sides are fixed through screws (bolts) in order to strengthen the connection with the lenticular sheet.

<Example 6: See FIG. 8>
In the second embodiment, the reinforcing member is a type of deformation that is fixed with a double-sided adhesive tape on the projector-side surface of the lenticular sheet.

<Example 7: See FIG. 9>
In Example 2, the reinforcing member is a type of deformation that is fixed with a double-sided adhesive tape on both the viewer side and the projector side of the lenticular sheet.
The reinforcing member on the observer side does not have to be attached over the entire upper side of the lenticular sheet, and may be attached intermittently at intervals in the clipped portion in FIG.

<Example 8: See FIG. 10>
A concave portion corresponding to the thickness of the reinforcing member is formed on the inner wall surface of the upper side of the frame facing the lenticular sheet side to which the reinforcing member is attached. By fitting the reinforcing member into the concave portion, the lenticular sheet A structure that is hung on the top side of the frame.
Compared with a type in which the reinforcing member is fixed to the inner wall surface of the upper side of the frame with a double-sided adhesive tape, the lenticular sheet is prevented from dropping due to a decrease in the adhesive strength of the double-sided adhesive tape.

<Example 9: See FIG. 11>
Fix the reinforcing member to the lenticular sheet with double-sided adhesive tape and reinforce it with clips.
Furthermore, in order to strengthen the joint with the lenticular sheet, it is fixed through screws (bolts).
At the position corresponding to the inner wall surface side of the upper side of the frame facing the head of the screw (bolt) or the clip, a recess (counterbore) for fitting them is formed.

<Example 10: See FIG. 12>
Fix the reinforcing member to the lenticular sheet with double-sided adhesive tape and reinforce it with clips.
The lenticular sheet and the reinforcing member are fixed with screws from the frame side until reaching the holding member.
In the holding member and the frame, a recess (counterbore) in which they are fitted is formed at a position corresponding to the inner wall surface facing the clip or screw.

<Example 11: See FIG. 13>
Fix the reinforcing member to the lenticular sheet with double-sided adhesive tape.
Fixing with screws from the holding member side to the reinforcing member.

The samples (screen + frame) according to the above examples were left in a 60 ° C. environment for 1 hour, and left in a 23 ° C. environment for 24 hours. No wrinkles or sagging was observed, and the environmental resistance was good.
In addition to the above embodiments, various modifications can be considered according to the combination of the elastic body, the clip, the screw, and the like, but improvements or modifications within the scope not departing from the gist of the present invention are appropriately performed. It is.

Explanatory drawing which shows an example of the transmission type screen (attachment method) which concerns on a prior art. Explanatory drawing which shows an example of the transmission type screen (attachment method) which concerns on a prior art. Explanatory drawing which shows an example of the transmission type screen (attachment method) by this invention. Explanatory drawing which shows an example of the transmission type screen (attachment method) by this invention. Explanatory drawing which shows an example of the transmission type screen (attachment method) by this invention. Explanatory drawing which shows an example of the transmission type screen (attachment method) by this invention. Explanatory drawing which shows an example of the transmission type screen (attachment method) by this invention. Explanatory drawing which shows an example of the transmission type screen (attachment method) by this invention. Explanatory drawing which shows an example of the transmission type screen (attachment method) by this invention. Explanatory drawing which shows an example of the transmission type screen (attachment method) by this invention. Explanatory drawing which shows an example of the transmission type screen (attachment method) by this invention. Explanatory drawing which shows an example of the transmission type screen (attachment method) by this invention. Explanatory drawing which shows an example of the transmission type screen (attachment method) by this invention.

Explanation of symbols

1 Lenticular sheet 2 Fresnel lens sheet 3 Housing (frame)
4 Holding member 5 Screw 6 Adhesive tape

Claims (8)

In a transmissive screen that is mounted on the display screen of a transmissive projection display by superposing a Fresnel lens sheet and a lenticular sheet and supporting and fixing the periphery to the frame,
In the lenticular sheet, a lens part composed of a cylindrical lens group is formed on the surface of the translucent substrate film with a cured product of a radiation curable resin, and the entire structure is flexible.
In the Fresnel lens sheet, a lens part is formed of a cured product of a radiation curable resin on the surface of a translucent base film, and a sheet having a light diffusion function is laminated and integrated on the film surface on the side opposite to the lens part. And is not flexible as a whole, and has a configuration with greater rigidity and thickness compared to the lenticular sheet,
On the upper side of the lenticular sheet, at least one side of the lenticular sheet has a strip-shaped reinforcing member attached along the entire upper side,
On the lower side of the lenticular sheet, the lenticular sheet and the Fresnel lens sheet are attached to each other on the surface of the lens part side by a double-sided adhesive tape along the lower side.
On the upper side of the frame, the Fresnel lens sheet and the lenticular sheet are pressed through a holding member so that the lenticular sheet is closely fixed to the upper side of the frame.
At the lower side of the frame, the Fresnel lens sheet suspended from the upper side of the frame and the lower side of the lenticular sheet are pressed through a holding member in a state where they are free ends,
A transmissive projection screen, wherein the lenticular sheet has a structure in which tension is applied downward due to the weight of the Fresnel lens sheet.   The transmission projection screen according to claim 1, wherein the strip-shaped reinforcing member is stuck in a state where it is in contact with a region having a width of 10 mm or more from the upper edge of the lenticular sheet. At the upper side of the lenticular sheet, with a strip-shaped reinforcing member attached to at least one side of the lenticular sheet via a double-sided adhesive tape, clip the lenticular sheet and the reinforcing member so that the cross-section becomes U-shaped. Fixed,
At the lower side of the lenticular sheet, the double-sided adhesive tape along the lower side is used to attach the lenticular sheet and the Fresnel lens sheet to each other on the lens side, and the cross-section is fixed with a clip so that it becomes a U-shape. The transmissive projection screen according to claim 1, wherein the transmissive projection screen is configured.   Where the lenticular sheet and the reinforcing member are fixed by the clip so that the cross section has a U-shaped cross section, a concave portion corresponding to the thickness of the clip is formed on the surface of the reinforcing member. The transmissive projection screen according to claim 1. On the upper side of the lenticular sheet, the strip-shaped reinforcing member is not stuck along the entire upper side,
The lenticular sheet and the reinforcing member are configured such that a strip-shaped reinforcing member is intermittently attached except for a portion where the cross section is fixed by a clip so as to have a U-shaped cross section. Item 4. The transmissive projection screen according to any one of Items 1 to 3. As a means for tightly fixing the lenticular sheet with the strip-shaped reinforcing member attached to the upper side of the frame,
6. The transmissive projection according to claim 1, wherein the transmissive projection is selected from at least one of joining with a double-sided adhesive tape, fixing with screws or bolts, and hanging from an upper part of the frame via an elastic body. screen.   A concave portion corresponding to the thickness of the reinforcing member is formed on the inner wall surface of the upper side of the frame facing the lenticular sheet side to which the strip-shaped reinforcing member is attached, and the reinforcing member is fitted into the concave portion. 6. The transmission projection screen according to claim 1, wherein the lenticular sheet is suspended while being hooked on the upper side of the frame. The holding member for tightly fixing the lenticular sheet to the upper side of the frame is
Above the frame, firmly fixed to the frame with screws or bolts,
The strip-shaped reinforcing member attached to the lenticular sheet is also firmly fixed by screws or bolts, and further reinforces the reinforcing member,
The transmissive projection screen according to any one of claims 1 to 7, further comprising a Fresnel lens sheet and being pressed against the upper side of the frame.