JPS61200783A - Light transmitting plate for display device - Google Patents

Abstract

PURPOSE:To remove moire or Newton rings to relieve a burden such as eye fatigue of the observer by placing slantingly a longitudinal array of groups of through-holes at an angle of 10 deg.-45 deg. against the longitudinal axis of the display screen. CONSTITUTION:An electro-magnetic shielding net 1 is formed by irradiating a laser beam to a metal film 3 to pierce numerous through-holes 2. In this case, the film 3 is formed of metal such as copper, iron or stainless steel having an electro-magnetic shielding capability with a thickness of 10-50mu, while surface treatment such as formation of copper oxide or silver film is applied to the surface of the film 3. The longitudinal array of the through-holes 2 on the film 3 is placed slantingly at an angle of 10 deg.-45 deg. against the longitudinal axis of the display surface. The number of prescribed holes in the transverse direction are pierced, while the position of irradiation of the spot light is shifted transversely each prescribed intervals, thereafter, a line is changed to shift longitudinally a prescribed amount. In line alignment, the position is shifted at an angle of 10 deg.-45 deg. against the preceding line to pierce the through-holes.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a light-transmitting face plate used for the screen of a display device such as a computer or a word processor.

<Prior Art> As is well known, a display device displays information by displaying light on a cathode ray tube screen. By the way, this cathode ray tube uses an electron gun to emit an electron beam to scan the fluorescent screen and draw bright spots that form characters according to the signal. Electromagnetic waves such as low frequencies, radio waves, and microwaves are emitted. These unnecessary electromagnetic waves are harmful to the human body and cause eye strain in observers, and there are various warnings from experts such as electromagnetic fields stimulating the central nervous system and causing stress in people. In recent years, this has become an important issue in terms of preserving the working environment. Therefore, a special translucent face plate for display equipment has been developed, which is placed in front of the screen of a cathode ray tube to shield electromagnetic waves and protect the viewer from their effects. It was proposed as shown in Japanese Patent Application No. 59-135789.

This structure consists of an electromagnetic shielding net with countless through holes and a translucent plate holding the shielding net in the form of a plate, and it blocks electromagnetic waves from the cathode ray tube without impairing the clarity of the image on the screen. The aim is to significantly reduce eye fatigue by blocking the effects of light and protecting the observer from its effects.

<Problems to be Solved by the Invention> By the way, if the arrangement of the through-holes of the electromagnetic shielding net is orthogonal along the horizontal and vertical axes of the display screen, moiré and Newton's rings are visually recognized to occur. Ta.

An object of the present invention is to provide a translucent picture plate for a display device having a structure capable of eliminating such moiré and Newton's rings.

Means for Solving the Problems> The present invention is characterized in that the vertical arrangement of the through holes is inclined by 106 to 45 inches with respect to the vertical axis of the display screen.

As a result of various experiments, it was confirmed that moiré and Newton's rings were eliminated when the vertical arrangement of the holes was tilted 10'-45'' with respect to the vertical axis of the display screen. Since the relationship between the scanning direction (horizontal direction) of the bright spot on the display screen and each through hole differs along the vertical direction, the screen as a whole is made as clear as possible and interference is less likely to occur. It is thought that this is because

<Example> The #L magnetic shielding net 1 can be formed by irradiating a metal film 3 with a laser beam and drilling countless through holes 2, as shown in FIGS. 1 to 3. In this case, the metal film 3 may be made of a metal such as copper, iron, or stainless steel that has an electromagnetic shielding ability of about 10 to 50 mm thick. Further, the surface of the metal film 3 may be subjected to various surface treatments such as forming a copper oxide coating or a silver coating.

Due to the copper oxide coating, the metal film 3 becomes gray or black and becomes matte. Therefore, when used in a display device, scattering of light is prevented and eye strain on the observer is reduced, and drilling processing using laser light, which will be described later, can be performed efficiently. Further, since oxidized steel and silver plating have shielding ability, they can be superimposed on a metal base material to increase the electric FB shielding ability.

The means for forming the shielding net 1 by the laser processing will be explained in more detail.

Regarding FIG. 3, a laser beam irradiated with a predetermined pulse passes through a mask a having a mold hole similar to the shape of the through hole 2 to be drilled, is focused by a focusing lens b, and the spot light is focused into a predetermined spot. The metal film 3 fixed to the holding device Mc
is irradiated.

The size of the image of the spot light formed on the metal film 3 is easily determined by changing the distance between the focusing lens b and the metal film 3. The metal film 3 is irradiated with one to several pulses of spot light at the same position to form a through hole 2. After drilling the through hole 2, the holding device WIC is moved and the spot light is irradiated again to the next drilling position on the metal film 3 to perform the drilling process, and this process is sequentially repeated at high speed. , countless through holes 2 are bored on the metal film 3. By moving the holding device C in relation to the number of pulses of the laser beam, its position can be precisely controlled.

The vertical arrangement of the through holes formed in the metal film 3 according to the main part of the present invention is
To install in rows at an angle of 45" to 45".

The irradiation position of the spot light is shifted at predetermined intervals in the transverse direction, and after a predetermined number of perforations in the transverse direction have been completed.

When performing a replacement by moving a predetermined amount in the vertical direction, the hole may be drilled at a position offset by 10 to 45 inches with respect to the through hole 2 in the previous row.

Figure 1 shows an example of the shape of the group of through holes,
The through hole 2 is a hexagonal hole.

In the above embodiment, the dimensions are X −0−150 mm,
7-0.070 am, Z = 0.02911, and the aperture ratio is about 65%. To enable such drilling.

As shown in Fig. 3, the mold hole of the mask a is hexagonal, and the amount of horizontal movement of the holding device 2tc is 0.150 m5, and as the predetermined number of horizontal holes is completed, it is moved by a predetermined amount in the vertical direction. Make a change.

At this time, the drilling position of the through hole 2 for each line change is 30 mm in the vertical direction.
They are shifted by @, so that they are aligned as shown in Figure 2.

FIG. 2 shows an embodiment in which a square through hole 2 is formed by the same method as described above, and the inclination angle is set to 30''.

In addition, the shape of the through hole 2 may be set in various ways, such as a circular shape.

The drilling process can be controlled by known means using a central control unit tcPU.

As shown in FIG. 4, the electromagnetic shielding net 1 can also be constructed by placing metal wires 4 having an electromagnetic shielding ability such as copper, iron, stainless steel, etc. in IIA. That is, it is made of a metal base material having electromagnetic shielding ability such as copper, iron, stainless steel, etc. A metal wire 4 with an outer diameter of about 50 mm is used, and this is knitted vertically and horizontally at intervals of 250 mm.

The shielding net 1 can have a porosity of about 50 to 70%. In this case as well, a copper oxide coating is used as described above.

A silver coating can also be applied.

In the shielding net l of this example, in order to incline the vertical arrangement of the through holes by 10'' to 45'' with respect to the vertical axis of the two display screens, the vertical lines 4a are inclined with respect to the horizontal lines 4b. This can be easily achieved.

In each of the above embodiments, the horizontal arrangement of the holes is arranged along the horizontal axis of the display screen, but the direction of the horizontal arrangement is not necessarily limited. may be arranged in an orthogonal relationship and the entire arrangement may be inclined from 10a to 45'' with respect to the display screen.

It consists of the above configuration. On the front and rear surfaces of the shielding net l.

As shown in FIG. 5, translucent plates 5.5 of acrylic resin or the like having a thickness of about 1 to 51 mm are joined to form a rectangular shape.

A holding frame 6 made of a material such as acrylic resin or vinyl chloride resin and having a U-shaped cross section is fitted around its outer periphery to form a light-transmitting face plate 7.

The light-transmitting face plate 7 having the above-mentioned structure can be constructed by attaching the holding frame 6 to the outer peripheral frame of the screen using double-sided adhesive tape 6, an appropriate locking hook, etc., or by using a suction cup provided on the outer periphery of the light-transmitting face plate 7. Attaches to existing display equipment. Further, so that the translucent plate 5.5 can be mounted in direct contact with the screen of a cathode ray tube, it can be curved to follow the screen to form a gently curved surface that bulges toward the front side. Further, the shielding net 1 between the translucent plates 5.5 is electrically drawn out to the outside and connected to earth.

<Effects of the Invention> As clarified by the above description, the present invention allows the vertical arrangement of the through holes to be arranged at 1 point with respect to the vertical axis of the display screen.
0 @ ~ 451' Because they are arranged in a row at an angle, moiré and Newton's rings are eliminated, and I! This has excellent effects such as reducing the burden of eye strain on the observer and enhancing the protective effect of the perforated face plate.

[Brief explanation of drawings]

The accompanying drawings show an embodiment of the present invention, and FIG. 1 shows a shielding net 1.
2 is an enlarged plan view of the shielding net 1 showing another embodiment of the through hole 2, FIG. 3 is a schematic diagram showing an example of laser processing means, and FIG. FIG. 5 is a longitudinal sectional side view of the light-transmitting face plate 7. FIG. 1;1! A shielding mesh 2; Through hole 3: Metal film 4; Metal wire m s, s: Transparent plate material 7; Transparent face plate 1 Figure 22 Figure 5

Claims (1)

[Claims] In a transparent face plate for a display device, which is formed by joining transparent plate materials before and after an electromagnetic shielding net having a large number of transparent holes,
A transparent face plate for a display device, characterized in that the vertical arrangement of the group of through holes is inclined at 10° to 45° with respect to the vertical axis of the display screen.