KR20140071111A

KR20140071111A - The Security Film for Display Device

Info

Publication number: KR20140071111A
Application number: KR1020120139085A
Authority: KR
Inventors: 김재진
Original assignee: 김재진
Priority date: 2012-12-03
Filing date: 2012-12-03
Publication date: 2014-06-11

Abstract

The present invention relates to a security film for a display device, which enables a display screen of a mobile phone, a notebook or a PDA, etc. to be shown only within a certain angle. More specifically, the security film for a display device can freely adjust a viewing angle and maintain the remarkably narrow viewing angle to enhance security. Furthermore, the security film can have the thin thickness, thereby preventing a decrease in a recognition rate for a user′s touch even in a case that the security film is attached to a touch screen. Also, the security film can be easily manufactured and remarkably reduce manufacturing costs. The security film for a display device according to the present invention comprises: a pair of protecting films which are made of transparent materials of light permeability, and are arranged, in parallel, to face to each other at certain intervals; and multiple light absorbing partitions which are made of opaque materials of non-permeability, and are vertically arranged at certain intervals in the space where the protecting films are spaced apart from each other at certain intervals upward and downward.

Description

[0001] The present invention relates to a security film for a display device,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a security film for a display device such as a mobile phone, a notebook computer, or a PDA, which is displayed only within a predetermined angle. More specifically, The thickness of the security film can be reduced while the security film is being reinforced. In particular, even when the security film is attached to the touch screen, deterioration of the recognition rate of the user's touch can be prevented, security films can be easily manufactured, To a security film for a display device.

BACKGROUND ART Portable information communication devices such as a notebook computer, a PDA and a mobile phone, and a cash dispenser of a financial institution store or input various data and personal information. Input and confirmation of personal data and information are displayed on the display screen of the corresponding device. .

In general, the conventional display screen has been developed for the purpose of improving a wide viewing angle and a high brightness, so that a person can easily observe the screen on both left and right sides of the display, and accordingly, personal information and important materials are exposed Such as the emergence of serious personal information leakage is emerging as a social problem.

In recent years, a security film for a display device has been developed to prevent leakage of personal information through such a display device. 1, a conventional security film for a display device has a structure in which a transparent light transmitting portion 101 and an opaque non-transparent portion 102 are alternately formed along a horizontal direction of the film. 2, a plurality of light transmissive films 110 and a non-transmissive film 120 are alternately bonded to each other and then cut to a predetermined thickness, And the transmissive portion was alternately formed.

As shown in FIGS. 3 and 4, the thus manufactured security film 100 suppresses side emission of light in a state of being attached to the front surface of various display devices 200, thereby reducing the viewing angle of the display device, Thereby preventing the screen displayed on the apparatus from being exposed to others.

However, in the conventional security film for a display device, since a plurality of light-transmissive films 110 and a non-transparent film 120 are both provided in a manufacturing process and a cutting process is performed after the alternate adhesive lamination process, Since the light transmitting portion 101 and the non-transmitting portion 102 are formed so as to correspond to the thickness of the security film, it is not possible to adjust the outgoing angle of light passing through the security film. A problem has occurred.

In this regard, Japanese Patent Application No. 10-0753591 (entitled " Security Film for Display Device and Method of Manufacturing the Same ") discloses a method of adjusting the viewing angle by changing the shape of the non-transmissive portion 102 However, since the additional material is required for forming the light transmitting portion 101, there is a limit to the material cost reduction,

The manufacturing process for forming the non-transmissive portion 102 is difficult and the conventional security film (the non-transmissive portion 102) is alternately arranged when the shape of the non-transmissive portion 102 for the viewing angle is changed 100, the same effect can be achieved by a method of narrowing the spacing distance of the non-transmissive portion 102. Particularly, when the non-transmissive portion 102 is arranged below a specific spacing distance, There is a problem that even a user can not clearly see the screen and there is a limitation in adjusting the viewing angle.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in order to solve the above-mentioned problems, and it is an object of the present invention to provide a security film which can reduce material cost for forming a light transmitting portion, do.

In addition, it is possible to restrict the viewing angle of both the left and right sides to a narrow range without reducing the interval between the non-transmissive portions, thereby providing a clear screen provided by the display device to a user viewing from the front,

It is possible to freely narrow the viewing angle to a predetermined range while keeping the thickness of the security film thin so that the security film can be easily attached to the display device and the security film is prevented from being detached from the screen during movement or storage of the display device In particular, even when the security film is attached on the touch screen, it is possible to minimize a decrease in the recognition rate of the user's touch.

According to an aspect of the present invention, there is provided a security film for a display device, comprising: a pair of protective films formed of a light-transmitting transparent material and disposed in parallel to face each other at a predetermined distance; And a plurality of light absorbing barrier ribs formed of a non-transparent opaque material, the pair of protective films being vertically arranged at a predetermined interval in a space spaced upward and downward by a predetermined distance A security film for a display device is provided.

In the security film for a display device according to the present invention, the space between the plurality of light absorbing barrier ribs may be provided with a viewing angle adjusting lens of a predetermined shape on an upper portion or a lower portion.

Preferably, the shape of the viewing angle adjusting lens may be a shape of a lenticular lens or a Fresnel lens,

More preferably, a transparent adhesion layer may be interposed between the pair of protective films and the light absorption barrier,

The plurality of light absorbing partition walls may be formed in a lattice shape perpendicular to each other,

In addition, the surface of the plurality of light absorbing partition walls may be formed as a matte.

The security film for a display device according to the present invention can reduce the cost of materials for forming a light transmitting portion in a security film in which a light transmitting portion and a non-transmitting portion are alternately arranged, , It is possible to facilitate the production of the security film.

Further, since the viewing angle can be freely adjusted, it is possible to restrict the viewing angle of both the left and right sides to a narrow range without reducing the interval between the non-transparent portions as in the prior art, thereby providing a clear screen provided by the display device to the user,

The viewing angle can be freely narrowed down to a predetermined range while keeping the thickness of the security film thin, so that the security film can be easily attached to the display device, and when the display device is moved or stored, It is possible to prevent the film from being released,

In particular, when the security film is attached on the touch screen, the decrease in the touch recognition rate of the display device with respect to the user's touch can be minimized.

1 is a perspective view showing a conventional security film;
FIG. 2 is a perspective view illustrating a manufacturing process of the security film of FIG. 1; FIG.
Fig. 3 is a state of use showing that the security film of Fig. 1 is attached on a screen of a display device; Fig.
Fig. 4 is a sectional view showing that the security film of Fig. 1 is attached on the screen of a display device; Fig.
5 is a cross-sectional view showing another embodiment of a non-transmissive portion of a conventional security film;
6 is a perspective view showing a security film for a display device according to the present invention;
7 is a sectional view showing a security film for a display device according to the present invention;
8 is a sectional view showing a viewing angle in a security film provided with a light absorption barrier (non-transmissive portion);
FIGS. 9A and 9B are cross-sectional views showing that a viewing angle adjusting lens is provided on the light-transmitting air layer of FIG. 6;
10A and 10B are views showing a security film for a display device according to the present invention, in which a transparent adhesive layer is interposed between a pair of protective films and a light absorbing partition wall, and a viewing angle adjusting lens is formed on a transparent adhesive layer Cross-section;
FIGS. 11A to 11D are cross-sectional views showing directions of refraction of light according to the structure of each security film; FIGS. And
12 is an exploded perspective view showing a plurality of light absorbing partition walls arranged in a lattice shape orthogonal to each other in the security film for a display device according to the present invention.

Hereinafter, embodiments of the present invention in which the above object can be specifically realized will be described with reference to the accompanying drawings. In describing the embodiments, the same names are denoted by the same reference numerals, and further description thereof will be omitted below.

6 is a perspective view showing a security film 1 for a display device according to the present invention, FIG. 7 is a cross-sectional view showing a security film 1 for a display device according to the present invention, FIG. 8 is a cross- Sectional view showing a view angle in the security film 1 provided with the non-transparent portion.

9A and 9B are cross-sectional views showing that a viewing angle adjusting lens is provided on the upper portion of the light transmitting air layer 30 of FIG. 6, and FIGS. 10A and 10B are views showing a case where the security film 1 for a display device according to the present invention Sectional view showing that a transparent adhesive layer 60 is sandwiched between a pair of protective films 10 and a light absorbing partition wall 20 and that a viewing angle adjusting lens is formed on the transparent adhesive layer 60 located on the top, 11A to 11D are cross-sectional views showing directions of refraction of light according to the structure of each security film 1, and FIG. 12 is a cross-sectional view of a security film for a display device according to the present invention, Like shape as shown in Fig.

As shown in FIGS. 6 and 7, the security film 1 for a display device according to the present invention includes a pair of protective films 10 arranged in parallel at positions spaced apart by a predetermined distance from each other, And a plurality of light absorbing barrier ribs 20 vertically arranged at a predetermined interval in a space between a pair of protective films 10 arranged in parallel and spaced apart from each other.

The security film for a display device according to the present invention has a light transmitting portion of a transparent material disposed between the light absorbing barrier ribs 20 so as to be alternately arranged with the light absorbing barrier ribs. The light transmitting part between the light absorbing barrier ribs 20 is omitted and only a plurality of the light absorbing barrier ribs 20 are disposed in a space between the pair of the security films 1 by a predetermined distance, 20, a light transmitting air layer 30 is formed. Therefore, the material cost for forming the conventional light transmitting portion can be omitted, and the cost for manufacturing the security film 1 can be remarkably reduced.

,

(Light absorption barrier 20 (20)), and H is a distance between the non-transmissive portion (20) and the non-transmissive portion (20), where n1 is the incident side refractive index, n2 is the exit side refractive index,? 1 is the incident angle,? 2 is the exit angle, )).

The viewing angle of the display device screen is proportional to the refractive index of the light transmitting portion (light transmitting air layer 30) and the spacing distance between the light absorbing partition walls 20 in accordance with FIG. 8 and Equation 1, Is inversely proportional to the height of the base 20. In order to improve the security of the device screen, it is effective to keep the screen viewing angle small. To do so, the refractive index of the light transmitting portion (light transmitting air layer 30) is made low and the distance between the light absorbing partition walls 20 And the height of the light absorption barrier 20 should be increased. In general, the refractive index of a transparent PET film or a PC film widely used as a material of a light transmitting portion is 1.5 to 1.52, and the refractive index of the light transmitting air layer 30 according to the present invention is larger than 1, It is possible to reduce the distance between the pair of protective films 10, and thus to reduce the thickness of the entire security film 1.

6 and 7, the protective film 10 located under the pair of protective films 10 is attached in contact with the screen of the display device, and the plurality of light absorbing barrier ribs 20 are attached to the lower The upper protective film 10 is formed on the upper surface of the light absorbing barrier rib 20 so as to be in contact with the upper surface of the protective film 10 at a predetermined interval. The protective film 10 may be a PET film or a PC film, which is a transparent transparent material. The light absorbing barrier rib 20 may be formed of a liquid phase in which black pigment such as epoxy, urethane, acrylate, And may be formed by curing the polymer compound.

9A and 9B, a viewing angle adjusting lens having a predetermined shape may be provided in a space between the light absorbing partition walls 20, that is, above or below the light transmitting air layer 30, The light transmitted through the pair of protective films, the light transmitting air layer 30 and the viewing angle adjusting lens is projected to a desired viewing angle through the viewing angle adjusting lens having various shapes as shown in Figs. 11c and 11d. .

9A and 9B, a lenticular lens 40 (Lenticular lens) or a Fresnel lens 50 (see FIG. 9A) is used as a typical viewing angle adjusting lens, (Fresnel lens) shape so that the viewing angle of the security film 1 can be narrowed.

10A and 10B, by forming a transparent adhesive layer 60 between the pair of protective films 10 and the light absorbing barrier rib 20, the pair of protective films 10, So that the light absorbing barrier rib 20 can be touched and firmly coupled,

The surface of the light absorbing partition wall is light-shielded so that light to be projected can be absorbed without being reflected by the surface of the light absorbing partition wall, and as shown in FIG. 6, However, as shown in FIG. 12, the plurality of light absorbing barrier ribs may be arranged in a lattice pattern orthogonal to each other so as to prevent the screen from being projected not only in the left and right but also in the upper and lower sides, .

As a method of forming the viewing angle adjusting lens, the viewing angle adjusting lens may be formed on the protective film 10, but may be formed on the transparent adhesive layer 60 as shown in FIGS. 10A and 10B.

Preferably, a hot-melt adhesive is applied to the inner surface of the upper and lower protective films 10 to a thickness of 5 to 15 μm to form the transparent adhesive layer 60, In order to adhere the barrier ribs 20 to the transparent adhesion layer 60, the pair of protective films 10 and the light absorption barrier walls 20 are pressed at a high temperature (not shown) So that the viewing angle adjusting lens can be easily formed on the transparent adhesive layer 60 through the molding die engraved.

11A to 11D are diagrams showing the directions of refraction of light transmitted on a security film in which the conventional light transmitting portion and the non-transmitting portion are alternately arranged, and the direction of refraction of the light transmitted through the light transmitting air layer 30 in the security film 1 according to the present invention When the lenticular lens 40 is formed on the upper part of the space between the light absorbing partition walls 20 in the refracting direction of the light, the Fresnel lens 50 is formed on the upper part of the space between the light absorbing partition walls 20 The direction of refraction of the transmitted light.

11A to 11D, in the security film 1 according to the present invention, the light transmitted through the light-transmitting air layer 30 passes through the conventional light-transmitting layer according to the difference in refractive index described above It can be seen that the viewing angle is narrower than the light, and that the viewing angle can be freely adjusted through the shape of the viewing angle adjusting lens formed on the space between the light absorbing partition walls.

As described above, the security film 1 for a display device according to the present invention can reduce the material cost of the security film 1 by forming the light transmitting air layer 30 by omitting the transparent material forming the conventional light transmitting portion 70 The refractive index of the light transmitting air layer 30 is lower than that of the PET film or the PC film used for forming the conventional light transmitting portion 70, 1) of the projection screen can be narrowed, thereby improving the security function.

In addition, by providing the viewing angle adjusting lens of a predetermined shape in the space between the light absorbing partition walls 20, the viewing angle of the screen of the display device can be freely adjusted and the user can freely adjust the viewing angle within a desired viewing angle The user who views the front of the screen can always view the image as it is on the screen of the display device,

The security film 1 can be easily attached to the display device and the security film 1 can be easily detached from the surface of the screen by making it possible to freely narrow the viewing angle to a predetermined range while keeping the thickness of the security film 1 small. In particular, when the security film 1 is attached on the touch screen, it is possible to minimize the degradation of the touch recognition rate of the display device with respect to the user's touch.

It is to be understood by those skilled in the art that the present invention may be embodied in many other forms without departing from the spirit and scope of the invention,

Accordingly, the above-described embodiments are to be considered illustrative and not restrictive, and all embodiments within the scope of the appended claims and their equivalents are intended to be included within the scope of the present invention.

1: Security film for display device according to the present invention
10: protective film 20: light absorption barrier
30: light transmitting air layer 40: lenticular lens
50: Fresnel lens 60: transparent adhesive layer
70: Light transmitting portion

Claims

A security film for a display device,
A pair of protective films formed of a transparent transparent material and arranged in parallel oppositely to each other with a predetermined distance therebetween; And
And a plurality of light absorbing barrier ribs formed of an opaque non-transparent material and arranged vertically at predetermined intervals in a space spaced apart by a predetermined distance between the pair of protective films. Security film for devices.

The method according to claim 1,
Wherein a space between the plurality of light absorbing barrier ribs is provided with a viewing angle adjusting lens of a predetermined shape on an upper portion or a lower portion thereof.

3. The method of claim 2,
The shape of the viewing-
Wherein the protective film is formed in a shape of a lenticular lens or a Fresnel lens.

4. The method according to any one of claims 1 to 3,
Wherein a transparent adhesive layer is interposed between the pair of protective films and the light absorbing partition wall.

4. The method according to any one of claims 1 to 3,
Wherein the plurality of light absorbing partition walls
Wherein the barrier film is formed in a lattice shape orthogonal to each other.

4. The method according to any one of claims 1 to 3,
Wherein the surface of the plurality of light absorption barrier walls is formed as a matte.