JP6055945B2 - Backlight type display device for portable device - Google Patents

Description

  The present invention relates to a portable device such as a cellular phone, and more particularly to a backlight type display device.

  Today, many mobile phones are equipped with a backlight type display panel. In the backlight method, since a backlight light source for illuminating the entire display area is provided on the back side of the liquid crystal display panel, there is a problem that light from the backlight light source leaks unnecessarily to the display side. Various techniques for preventing light leakage have been proposed.

  For example, Patent Document 1 discloses a liquid crystal display device that prevents light leakage by covering the end face of a light guide that guides light from a backlight light source with a covering protrusion of an adhesive sheet. Patent Document 2 discloses a display device that prevents light leakage from a backlight light source by providing a light-shielding portion that covers an area other than the display area of the display panel and partially projecting the light-shielding part. ing. The display devices disclosed in these patent documents have a structure in which an adhesive sheet and a light-shielding portion are assembled with a plurality of components such as a frame and a transparent substrate.

JP 2002-107715 A JP 2006-154383 A

  However, in the above-described patent document, since an adhesive sheet having a protruding portion for preventing light leakage from the backlight is incorporated in the frame, a light leakage preventing sheet or the like must be prepared separately. For this reason, the number of parts increases, there is a problem that the weight reduction of the mobile phone is hindered and the manufacturing process becomes complicated.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a backlight in a portable device that can effectively prevent backlight light leakage and can reduce the number of parts and achieve weight reduction and easy manufacture of the portable device. The object is to provide a light-type display device.

  A backlight type display device according to the present invention is a backlight type display device in a portable device, and transmissive display means having a predetermined display range, and the display range of the transmissive display means is irradiated with light from behind. Backlight means, a mounting frame for mounting the transmissive display means and the backlight means in a frame, and a transparent panel covering the mounting frame, and the display range on the inner side of the transparent panel. A display in which a plurality of window frame printing layers forming an enclosing window frame are formed, and a light shielding printing layer covering at least a gap between the inner frame of the mounting frame and the edge of the transmissive display unit is formed thereon. The light-shielding print layer is printed and formed by receding by an offset amount that absorbs a printing error from the parting line of the window frame, and the first window frame print layer is formed on the transparent panel. The second window frame printing layer is printed so as to form the parting line, and the light-shielding printing layer is further printed on the offset line from the parting line. It is characterized by being printed with a receding amount.

  According to the present invention, backlight light leakage can be effectively prevented, and the number of components can be reduced to achieve weight reduction and easy manufacture of a portable device.

(A) is a top view which shows the external appearance of the display apparatus of the portable apparatus by one Embodiment of this invention, (B) is the aa sectional view taken on the line. It is a plane block diagram which shows the internal structure of the display apparatus shown to FIG. 1 (A). (A) is the cross-sectional block diagram which expanded the b part of FIG. 1 (B), (B) is a cross-sectional block diagram which shows the comparative example. (A) is typical sectional drawing which shows the printing layer structure by this embodiment, (B) is typical sectional drawing which shows the printing layer structure as the comparative example.

  Hereinafter, an embodiment of the present invention will be described in detail using a liquid crystal display (LCD) as a backlight-type transmissive display device and taking a mobile phone equipped with an LCD as an example.

  As shown in FIG. 1, an acrylic transparent panel 11, LCD 13, backlight light guide 14, and mounting frame 15 are mounted on the display side of the housing 10 of the mobile phone according to the present embodiment. On the back side of the transparent panel 11, a print layer of a display unit window frame, which will be described later, is formed, and an edge thereof forms a parting line 12. A display range 13d of the LCD 13 is located within a rectangular display portion window frame formed by the parting line 12. A backlight light guide 14 is overlaid on the back side of the LCD 13, and the LCD 13 and the backlight light guide 14 are fixed in the mounting frame 15. The mounting frame 15 is fixed to the recess of the housing 10, and the transparent panel 11 is attached to the main surface of the housing 10 so as to protect the LCD 13 attached to the mounting frame 15.

  As shown in FIG. 2, a claw portion 14 a is formed at a predetermined position of the backlight light guide portion 14, and the backlight light guide portion 14 is positioned and fixed by fitting the claw portion 14 a to the mounting frame 15. The The LCD 13 is placed on the backlight light guide 14 in an overlapping manner. Since the backlight light guide unit 14 is disposed corresponding to the display area 13 d of the LCD 13, the size thereof is slightly smaller than that of the LCD 13. Therefore, the claw portion 14 a passes under the LCD 13 and is fitted to the mounting frame 15.

  The backlight light guide 14 has a function of spreading light from a backlight light source (such as a light emitting diode) (not shown) over the entire LCD display range 13d. For this reason, light is also guided to the claw portion 14a, which leaks to the front side from the gap 21 between the LCD 13 and the mounting frame 15. In general, since the LCD determines the outer shape by breaking glass, the inner frame size of the mounting frame 15 is formed larger in consideration of the presence of glass burrs. For this reason, some gap exists between the LCD 13 and the mounting frame 15, and light leaks through the gap.

  As shown in FIG. 3A, according to one embodiment of the present invention, the window frame region inside the transparent panel 11 and outside the parting line 12 is decorated by silk printing. In the case of a light color, an appearance color A layer 30a such as pearl is laminated on the first layer, an appearance color B layer 30b such as white is laminated on the second layer, and a light-shielding printing layer 30c such as silver or black is further laminated on the third layer. Is printed. Since the light-shielding printing layer 30c is formed in the same manner as other appearance color layers using a printing technique, it is easy to manufacture and can be assembled by simply printing on the transparent panel 11, and the effect of reducing the number of parts can be obtained. You can also.

  However, when the printing technique is used, it is usually necessary to cope with a new technical problem that a deviation of about 0.15 mm occurs for each printing. For example, when printing a plurality of color layers on the periphery of the display area of the display panel, if there is such a print misalignment, the color misalignment will be noticeable around the display area, resulting in poor appearance. In particular, when printing is performed by further overlapping the light shielding layer on the pearl layer and the white layer, the appearance of the display panel is greatly deteriorated if the light shielding layer is shifted and exposed.

  Therefore, according to the present embodiment, the appearance color A layer 30a is printed and formed on the transparent panel 11 with an offset amount of about 0.2 mm outside the parting line 12, and the parting line 12 is formed thereon. The B layer 30b is printed. The edge (parting line 12) of the appearance color B layer 30b is arranged so as not to cover the LCD display range 13d. Furthermore, on the outer side of the parting line 12, a light shielding printing layer 30c is printed with an offset amount of about 0.2 mm.

  That is, as shown in FIG. 4A, the appearance color A layer 30a and the light-shielding print layer 30c are printed and formed on the outside of the parting line 12 with an offset amount of about 0.2 mm. Therefore, even when printing misalignment occurs, it does not enter inside the edge (parting line 12) of the appearance color B layer 30b.

  Thus, since the light-shielding print layer 30c is printed and formed with an offset amount of about 0.2 mm outside the parting line 12, light leaking from the gap 21 between the LCD 13 and the mounting frame 15 even if printing misalignment occurs. Can be effectively blocked by the light-shielding printing layer 30c.

  In the comparative example shown in FIG. 3B, the parting line 12 of the display unit window frame is configured by the appearance color A layer 40a, and the appearance color B layer 40b is further outwardly offset from the appearance color A layer 40a. The light-shielding print layer 40c is printed by offsetting. In this case, as shown in FIG. 4B, since the offset amounts from the parting line 12 to the appearance color B layer 40b and from the appearance color B layer 40b to the light-shielding print layer 40c are about 0.2 mm, The offset amount from 12 to the light-shielding print layer 40c is about 0.4 mm. Generally speaking, since the light shielding layer is usually formed last, the positional deviation of 0.2 mm × (n−1) on average from the end of the first layer to the end of the nth layer (light shielding layer). Will occur. When the position of the light shielding layer is retreated in this manner, there may be a case where light leakage from the backlight light source cannot be effectively prevented.

  That is, the gap 21 between the LCD 13 and the mounting frame 15 that should be covered with the light-shielding print layer 40c is not covered, and light from the range from the appearance color A layer 40a to the light-shielding print layer 40c of the transparent panel 11 leaks. Cause. As one countermeasure, it is conceivable to reduce the display portion window frame surrounded by the parting line 12 of the transparent panel 11. However, assuming the worst case in consideration of printing misalignment or assembly misalignment, the parting line 12 may cover a part of the LCD display range 13d.

  On the other hand, according to the present embodiment, such light leakage from the gap 21 is caused by a printing configuration including the appearance color A layer 30a, the appearance color B layer 30b, and the light shielding print layer 30c shown in FIG. Can be prevented. That is, the offset amount from the parting line 12 of the display unit panel to the light-shielding print layer 30c is changed from about 0.4 mm shown in FIG. 4B to FIG. 4A without changing the size of the display unit window frame. The backlight leakage light of the display LCD that could not be covered with an offset amount of about 0.4 mm can be covered.

  In recent mobile phones, it is required to finish the display panel with various colors from the design aspect. In order to answer such design requirements in detail, the use of printing technology can be considered. For example, in order to realize a light color on the display panel, a technique for printing a pearl layer on the first layer and a white layer on the second layer is required. The light-shielding print layer 30c according to the present embodiment also has an advantage that such a printing technique can be used as it is.

  The present invention can be applied to a portable device having a display unit using a backlight type LCD. Examples of portable devices include cellular phones, PHS (Personal Handyphone System), PDAs (Personal Digital Assistants), electronic dictionaries, calculators, notebook computers, and portable televisions.

10 Housing 11 Transparent panel 12 Parting line 13 LCD
13d LCD display range 14 Back light guide 15 Mounting frame 21 Gap 30a Appearance color A printing layer 30b Appearance color B printing layer 30c Light-shielding printing layer

Claims (2)

A backlight type display device in a portable device,
Transmissive display means having a predetermined display range;
Backlight means for irradiating light from behind the display range of the transmissive display means;
A mounting frame for mounting the transmissive display means and the backlight means in a frame;
A transparent panel covering the mounting frame;
And a plurality of window frame printing layers forming a window frame surrounding the display range are formed inside the transparent panel, and further on the inner frame of the mounting frame and the edge of the transmissive display means A light-shielding print layer covering at least the gap of the display device,
The light-shielding print layer is printed back by an offset amount that absorbs a printing error from the parting line of the window frame,
A first window frame printing layer is printed on the transparent panel so as to recede from the parting line by the offset amount, and a second window frame printing layer is printed thereon to form the parting line, The display device is characterized in that the light-shielding print layer is printed back by the offset amount from the parting line.   A mobile phone equipped with the display device according to claim 1.

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