JPH0981048A - Light transmission plate device - Google Patents

Light transmission plate device

Info

Publication number
JPH0981048A
JPH0981048A JP26243895A JP26243895A JPH0981048A JP H0981048 A JPH0981048 A JP H0981048A JP 26243895 A JP26243895 A JP 26243895A JP 26243895 A JP26243895 A JP 26243895A JP H0981048 A JPH0981048 A JP H0981048A
Authority
JP
Japan
Prior art keywords
light
guide plate
light guide
prism
receiving
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP26243895A
Other languages
Japanese (ja)
Inventor
Honami Harada
保波 原田
Original Assignee
Beam Denshi Kogyo Kk
ビーム電子工業株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Beam Denshi Kogyo Kk, ビーム電子工業株式会社 filed Critical Beam Denshi Kogyo Kk
Priority to JP26243895A priority Critical patent/JPH0981048A/en
Publication of JPH0981048A publication Critical patent/JPH0981048A/en
Pending legal-status Critical Current

Links

Abstract

PROBLEM TO BE SOLVED: To form the projecting surface of a front or rear surface which are projecting surface or an opposite surface as a uniform light emitting surface by providing this front or rear surface on a prism reflection surface and forming the prism reflection surface variably in its angle, pitch or depth or fixedly in one thereof and variably in the other two. SOLUTION: The rear surface on one side edge 2a of a light transmission plate 1 is provided with a recessed light receiving part 3 opening to a required shape. This light receiving part 3 is internally provided with an LED in such a manner that at least the light emitting part thereof may be inserted and arranged into this part. The front surface which is the projecting surface of the light transmission plate 1 is previously installed on the projecting matte surface 5 formed with satin patterns. The rear surface which is the surface opposite to this projecting matte surface 5 is provided with a reflection surface 7 to act the matte surface 5 as a uniform emitting surface by varying the angle, pitch and depth of the parallel striped groove prisms. While all of the angle, pitch and depth of the striped groove prism of the reflection surface 7 may be made variable, the matte surface 5 may be formed as the uniform light emitting surface as well by forming one thereof fixed and the other two variable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light guide plate device for uniformly irradiating a liquid crystal dial plate, an image plate or the like of a small portable personal computer, a mobile phone or the like.

[0002]

2. Description of the Related Art Conventionally, a light guide plate which receives a light source from a side edge of a plate and uniformly projects light on the surface of the plate has a strip shape in which a reflection surface is gradually widened as the distance from the light source increases. Generally, a reflective film is applied to the back surface of the plate.

Further, the surface of the conventional light guide plate is a smooth surface, and the illuminance is uneven, and in order to average this, a diffuser plate composed of two prism plates or the like is arranged between the light guide plate and the liquid crystal plate. It is a thing.

[0004]

Since the conventional uniform reflecting surface device is manufactured by a method such as silk printing of the strip-shaped reflecting film, it takes a lot of time and effort to manufacture it, and it is not suitable for mass production. Since another material is attached, it absorbs light and the reflection efficiency is not good.

Further, not only the cost is increased by arranging a diffusion plate composed of two prism plates but the thickness thereof is increased,
It has the drawback of being bulky.

[0006]

[Means for Solving the Problems] One end surface, a plurality of end surfaces of a light guide plate molded into a flat plate using a transparent plastic material,
A light receiving portion for receiving a light source such as a cold cathode tube, a light bulb or an LED, which is an appropriate light emitting body, is provided on the front surface or the back surface near the one side edge, or the surface or the back surface facing the plurality of side edges, and the surface serving as the light emitting surface of the light guide plate or The back side is provided on the matte surface with a satin pattern,
The front surface or the back surface opposite to the projection surface can be changed in angle, pitch, depth or height, or one of the angle, pitch and depth or height can be fixed, and the other two can be changed. The light guide plate device is characterized in that it is provided on parallel prismatic reflecting surfaces of linear grooves or ridges, and the light projecting surface of the front surface or the back surface of the light guide plate becomes a uniform light emitting surface.

A light receiving portion for receiving a light source which is a light emitting body such as a cold cathode tube, a light bulb or an LED is provided on the front surface or the back surface near one side edge or a plurality of side edges of the light guide plate, and the surface corresponding to the light receiving section or The back surface may be provided with a required width on the corresponding prism reflecting surface of parallel stripes or ridges having a required angle, pitch, and depth or height.

A concave light receiving portion for receiving a light source such as a cold cathode tube, a light bulb or an LED, may be provided on one end surface or a plurality of end surfaces of the light guide plate.

A concave light receiving portion for receiving a light source which is a light emitting body such as a cold cathode tube, a light bulb or an LED may be provided on a front surface or a back surface near one side edge or a plurality of side edges of the light guide plate.

The surface or the back surface of the light guide plate which faces one side edge or a plurality of side edges of the front surface or the back surface, which corresponds to the concave light receiving portion, is formed into a parallel shape having a required angle, pitch, and depth or height. A required width may be provided on the corresponding prism reflecting surface of the groove or the ridge.

The front surface or the back surface which is the light projecting surface of the light guide plate intersects the matte surface of the matte pattern with the parallel groove or ridge on the opposite prism reflecting surface at the required angle, and the required angle, Pitch, depth or height of constant or variable, or one of these angles, pitch, depth or height is constant and the other two are variable: parallel prismatic grooves or ridges May be provided in the.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION A light receiving portion for receiving a light source which is a light emitting body such as a cold cathode tube, a light bulb or an LED is provided on a back surface of a light guide plate molded into a flat plate using a transparent plastic material, near the corresponding side edge. The light-transmitting surface of the light guide plate is provided on the matte surface of the matte pattern, and the back surface, which is the opposite surface of the light-transmitting surface, is formed with parallel angle grooves with variable pitch and depth. The light guide plate device is characterized in that the light projecting surface on the surface of the light guide plate is a uniform light emitting surface.

On the back surface of the light guide plate near the corresponding side edge, a cold cathode tube,
A light receiving part for receiving a light source such as a light bulb or an LED, which is an appropriate light emitting body, is provided, and the surface corresponding to the light receiving part is angled, pitched,
And the required width is provided on the corresponding reflecting surfaces of the parallel convex stripes having a constant depth.

A concave light receiving portion for receiving a light source such as a cold cathode tube, a light bulb, an LED, or the like is provided on one end surface or a plurality of end surfaces of the light guide plate.

A concave light receiving portion for receiving a light source such as a cold-cathode tube, a light bulb or an LED is appropriately provided on the back surface of the light guide plate near one side edge or the corresponding side edge.

The surface which becomes the light projecting surface of the light guide plate intersects with the matte surface of the matte pattern at the required angle with the parallel groove or ridge on the opposite prism reflecting surface, and at the required angle,
It is provided on the projection prism surface of the parallel groove having a constant pitch, depth or height.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below. FIGS. 1 to 5 show a first embodiment, 1 is a light guide plate, and a flat plate having a required width, length and thickness using a transparent plastic material. And a recessed light receiving portion 3 which is opened in a required shape on the back surface of the one side edge 2a, and LE is provided in the recessed light receiving portion 3.
D4 is provided so that at least the light emitting portion can be inserted and arranged,
The light-projecting surface of the light guide plate 1 is provided with a satin pattern on the light-projecting mat surface 5, and the back surface opposite to the light-projecting mat surface 5 has parallel stripe groove prisms as shown in FIG. 6a
The prism reflection surface 7 is provided so that the projection mat surface 5 becomes a uniform light emitting surface by differentiating the angle θ, the pitch p, and the depth h.

The satin pattern on the light-projecting mat surface 5 is provided by blasting particles of mesh # 500 to # 800.

Since there are many conditions for light diffusion, the illuminance at each point is measured to determine the angle θ, pitch p, and depth h of the groove prism 6a.

The grooved prism 6a of the prism reflecting surface 7
The angle .theta., The pitch p, and the depth h may all be variable, but one of them is fixed and the other two are variably set so that the light emitting mat surface 5 becomes a uniform light emitting surface. You can Further, as shown in FIG. 12, the linear groove prism 6a of the prism reflecting surface 7 is a ridge prism 6b.
It can be.

Next, a description will be given of specific examples thereof. Unit 1 mm Example 1 of groove groove prism 6a Angle 100 ° Constant (apex angle) Depth 0.002 to 0.149 Variable pitch 0.15 to 0.5 Example 2 of variable streak prism 6a Pitch 0.5 & 0.1 Constant depth 0.05-0.01 Variable angle 90 ° -110 ° Variable (apex angle) Example 3 of ridge prism 6b Pitch 0. 1 to 0.8 Variable depth 0.002 to 0.25 Variable angle 30 ° to 85 ° Variable (tilt angle) Example of lamp used a Cold cathode tube 2.6 mm diameter Emission length 230 mm b Light bulb 2.0 mm Diameter height 5 mm c LED 6 lights, light guide plate size a 232 × 178 b 26 × 40 c 90 × 118

On the surface of the light guide plate 1 corresponding to the recessed light receiving portion 3, a ridge prism 8 having a required angle .theta.1, a pitch p1 and a height h1 is provided with a required width, and a corresponding prism reflecting surface 9 is provided. The ridge prism 8 may be a groove prism.

Next, a specific example of the ridge prism 8 will be described. Unit mm Pitch 0.1 Constant depth 0.042 Constant angle 100 ° Constant (valley angle)

As shown in FIGS. 4 and 5, the light guide plate 1 may have the front surface and the side surface shielded and reflected by the window frame type reflective curtain 10 and the back surface shielded and reflected by the reflective curtain 11.

The concave light receiving portion 3 of the light guide plate 1 is formed in an arc shape as shown in FIG. 3 (which diffuses the light of the LED evenly), but as shown in FIG. Alternatively, it may have another shape (not shown). Further, in order to increase the brightness, it can be easily performed by increasing the number of point light sources such as LEDs.

The light guide plate 12 is the second embodiment, and the concave light receiving portion 3 has the light guide plate 1 as shown in FIGS.
It is provided on the back surfaces of the one side edge 2a and the other side edge 2b corresponding to each other. In this case, it goes without saying that the projection prism 8 may be provided on the front surface so as to have the required width in correspondence with the concave light receiving portion 3 to provide the corresponding prism reflection surface 9, but the angle θ of the prism 6 on the back surface and the pitch p. , And depth h also
It is based on the same theory as that of the first embodiment.

Although not shown, in the light guide plate 12 of the second embodiment, the front surface and the side surface may be shielded and reflected by the window frame type reflection screen 10 and the back surface may be shielded and reflected by the reflection screen 11.

The light guide plate 13 is the third embodiment, and as shown in FIG. 10, the matte projection surface 5 of the light guide plate 12 of the second embodiment, which is the light projection surface, has a matte pattern. In addition, the parallel groove prism 6a on the prism reflection surface 7 on the opposite back surface
And intersect, for example, 90 degrees and, for example, an angle of 100
° (valley angle), pitch (p) 0.2 mm, depth (h) 0.
A parallel groove prism 14 having a width of 042 mm and a width of the diffusion band mat surface 5a of 0.1 mm is provided on the light projecting surface and on the light projecting mat prism surface 15. Although not shown, the groove prism 14 may of course be a ridge prism.

The cold cathode tubes 16 may be arranged similarly to the light guide plate 1 as shown in FIG. 14 or to the light guide plates 12 and 13 (not shown). Although not shown, the bulb 4 and the cold cathode fluorescent lamp 16 are also included in the bulb.
Similarly to the above, the light guide plate 1, the light guide plate 12, and the light guide plate 13 may be arranged.

[0030]

According to the present invention, as described above, the irradiation light from the light emitting body can be efficiently incident on the light guide plate from the light receiving portion.

Further, according to the present invention, the front surface or the back surface opposite to the light projecting surface is provided on the prism reflecting surface, and the angle, pitch, and depth of the prism reflecting surface are variable or one of them is fixed, The other two can be variably provided and the front or back light projecting surface can be made to be a uniform light emitting surface.

Further, according to the present invention, since the front surface or the back surface serving as the light projecting surface of the light guide plate is provided on the matte diffusing matte surface, diffused light can be projected, and the conventional two prism diffuser plates, vertical and horizontal, are not required. This contributes to reduction of manufacturing cost and reduction of thickness of the light guide plate device.

In particular, the matte projection surface 5 having a matte pattern on the surface serving as the projection surface intersects with parallel stripe grooves or projecting prisms on the prism reflecting surface on the opposite back surface at an angle of 90 ° to 10 ° minus. By providing a groove or a ridge prism on the light-projecting surface, the uniformity of brightness was increased and the brightness was doubled with the same light-emitting body used as the projection mat / prism surface.

Therefore, the present invention provides a small portable personal computer,
It is possible to provide a light guide plate device for irradiating a liquid crystal dial plate, an image plate, etc. of a mobile phone or the like with high brightness and uniformity, as thin as possible, and at low cost.

[Brief description of drawings]

FIG. 1 is a cross-sectional side view showing a first embodiment of a light guide plate alone in which a light source of the light guide plate device of the present invention is arranged at one side edge.

FIG. 2 is likewise a plan view of a surface which is a light projecting surface thereof.

FIG. 3 is a bottom view of the back surface that is the prism reflection surface of the same.

FIG. 4 is likewise a partially enlarged cross-sectional view of the relevant part.

FIG. 5 is a partially enlarged perspective view of the main part of the same.

FIG. 6 is also a partial bottom view showing another embodiment of the shape of the recessed light receiving portion into which the light emitting portion of the LED is inserted.

FIG. 7 is a cross-sectional side view showing a second embodiment of a light guide plate in which concave light receiving portions into which light sources are inserted are provided on both side edges facing each other.

FIG. 8 is likewise a plan view showing a second embodiment of the surface which is the light projecting surface.

FIG. 9 is a second rear surface of the prism, which is a reflective surface of the prism.
It is a bottom view showing an example of.

FIG. 10 is a third structure in which the light projecting surface of the light guide plate is a prism projecting surface.
It is an external appearance perspective view which shows Example.

FIG. 11 is an enlarged explanatory view of the cut of the groove prism forming the prism reflecting surface in the first, second and third embodiments.

FIG. 12 is an enlarged explanatory view of the cut of the ridge prism constituting the prism reflecting surface in the first, second and third embodiments.

FIG. 13 is an enlarged explanatory diagram of the cut of the ridge prism on the corresponding prism reflection surface of the light guide plate.

FIG. 14 is an enlarged partial side view for explaining how the cold cathode tubes and the end face light receiving portions of the light guide plate are arranged.

[Explanation of symbols]

 1 Light guide plate 2a One side edge 2b Other side edge 3 Recessed light receiving part 4 LED 5 Light emitting mat surface 6a Streak prism 6b Ridge prism 7 Prism reflection surface 8 Ridge prism 9 Corresponding prism reflection surface 10 Window frame type reflection screen 11 Reflection screen 12 Light guide plate 13 Light guide plate 14 Strip groove prism 15 Light emitting mat / prism surface 16 Cold cathode tube

Claims (6)

[Claims]
1. A cold-cathode tube, a light bulb, on one end surface, a plurality of side end surfaces, a front surface or a back surface near one side edge, a front surface or a back surface near a plurality of side edges, which is formed into a flat plate using a transparent plastic material. A light receiving portion for receiving a light source which is an appropriate light emitting body such as an LED is provided, and a front surface or a back surface serving as a light projecting surface of the light guide plate is provided on a matte surface having a satin pattern, and a surface opposite to the light projecting surface or Angles, pitches, depths or heights of the back surface are variable, or one of the angles, pitches, and depths or heights is constant, and the other two are variable and parallel muscle grooves or ridges are formed. The light guide plate device, characterized in that it is provided on the prism reflection surface and the light projecting surface on the front surface or the back surface of the light guide plate becomes a uniform light emitting surface.
2. A light receiving portion for receiving a light source, which is a light emitting body such as a cold cathode tube, a light bulb or an LED, is provided on a front surface or a back surface near one side edge or a plurality of side edges of the light guide plate, and corresponds to the light receiving section. 2. The light guide plate according to claim 1, wherein the front surface or the back surface is provided with a required width on a corresponding prism reflection surface of parallel groove or ridge having a required angle, pitch, and depth or height. apparatus.
3. A light receiving plate having a concave light receiving portion for receiving a light source which is a light emitting body such as a cold cathode tube, a light bulb or an LED, is provided on one end surface or a plurality of side end surfaces of the light guide plate. Item 2. The light guide plate device according to item 2.
4. A concave light receiving portion for receiving a light source, which is a light emitting body such as a cold cathode tube, a light bulb or an LED, is provided on a front surface or a back surface near one side edge or a plurality of side edges of the light guide plate. The light guide plate device according to claim 1 or 2.
5. The front surface or the back surface of the light guide plate facing one side edge or a plurality of side edges facing the concave light receiving portion of the front surface or the back surface having a required angle, pitch, and depth or height. A corresponding prism reflecting surface having parallel streak grooves or ridges is provided with a required width.
The light guide plate device according to claim 2 or 3.
6. A light-transmitting surface of a light guide plate, the front surface or the back surface intersecting with a matte surface having a matte pattern at a required angle with parallel stripe grooves or ridges on the opposite prism reflecting surface, and Projection of parallel ridges or ridges that make the angle, pitch, depth or height constant or variable, or make one of the angles, pitch, depth or height constant and the other two variable. The light guide plate device according to claim 1, wherein a prism surface is provided.
JP26243895A 1995-09-14 1995-09-14 Light transmission plate device Pending JPH0981048A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP26243895A JPH0981048A (en) 1995-09-14 1995-09-14 Light transmission plate device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP26243895A JPH0981048A (en) 1995-09-14 1995-09-14 Light transmission plate device

Publications (1)

Publication Number Publication Date
JPH0981048A true JPH0981048A (en) 1997-03-28

Family

ID=17375798

Family Applications (1)

Application Number Title Priority Date Filing Date
JP26243895A Pending JPH0981048A (en) 1995-09-14 1995-09-14 Light transmission plate device

Country Status (1)

Country Link
JP (1) JPH0981048A (en)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1115393A (en) * 1997-06-09 1999-01-22 Lumitex Inc Display panel assembly
JP2001067915A (en) * 1999-08-25 2001-03-16 Hayashi Telempu Co Ltd Surface lighting system
WO2001063347A1 (en) * 2000-02-28 2001-08-30 Omron Corporation Surface light source, method for manufacturing the same and apparatus using it
US6669350B2 (en) 2000-12-14 2003-12-30 Mitsubish Rayon Co., Ltd. Planar light source system and light deflecting device therefor
US6854857B2 (en) 2002-06-11 2005-02-15 Fujitsu Limited Electronic apparatus, liquid crystal display device and light guide plate
JP2005353599A (en) * 2004-06-11 2005-12-22 Valeo Vision Vehicle lighting or signaling system with light guide
WO2006013969A1 (en) * 2004-08-06 2006-02-09 Kuraray Co., Ltd. Light guide plate, production method therefor, and surface light source device provided with it
JP2008004948A (en) * 2006-06-09 2008-01-10 Philips Lumileds Lightng Co Llc Low profile side emitting led
KR100798680B1 (en) * 2005-11-10 2008-01-28 오완호 The luminous device using light emitting diodes
US7527411B2 (en) 2006-02-22 2009-05-05 Citizen Electronics Co., Ltd. Lightguide plate of a double-sided illumination backlight and a double-sided liquid crystal display unit using the backlight
CN102086995A (en) * 2009-12-08 2011-06-08 乐金显示有限公司 Backlight unit and liquid crystal display device having the same
WO2012050121A1 (en) * 2010-10-15 2012-04-19 シャープ株式会社 Backlight unit

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1115393A (en) * 1997-06-09 1999-01-22 Lumitex Inc Display panel assembly
JP2001067915A (en) * 1999-08-25 2001-03-16 Hayashi Telempu Co Ltd Surface lighting system
WO2001063347A1 (en) * 2000-02-28 2001-08-30 Omron Corporation Surface light source, method for manufacturing the same and apparatus using it
US7014349B2 (en) 2000-02-28 2006-03-21 Omron Corporation Surface light source, method for manufacturing the same and apparatus using it
US6669350B2 (en) 2000-12-14 2003-12-30 Mitsubish Rayon Co., Ltd. Planar light source system and light deflecting device therefor
US7380969B2 (en) 2000-12-14 2008-06-03 Mitsubishi Rayon Co., Ltd. Planar light source system and light deflecting device therefor
US6854857B2 (en) 2002-06-11 2005-02-15 Fujitsu Limited Electronic apparatus, liquid crystal display device and light guide plate
JP2005353599A (en) * 2004-06-11 2005-12-22 Valeo Vision Vehicle lighting or signaling system with light guide
EP1780464A4 (en) * 2004-08-06 2009-08-19 Kuraray Co Light guide plate, production method therefor, and surface light source device provided with it
JP4802094B2 (en) * 2004-08-06 2011-10-26 株式会社クラレ Light guide plate, method for manufacturing the same, and surface light source device including the same
EP1780464A1 (en) * 2004-08-06 2007-05-02 Kuraray Co., Ltd. Light guide plate, production method therefor, and surface light source device provided with it
JPWO2006013969A1 (en) * 2004-08-06 2008-05-01 株式会社クラレ Light guide plate, method for manufacturing the same, and surface light source device including the same
WO2006013969A1 (en) * 2004-08-06 2006-02-09 Kuraray Co., Ltd. Light guide plate, production method therefor, and surface light source device provided with it
US7883254B2 (en) 2004-08-06 2011-02-08 Kuraray Co., Ltd. Light guide plate, production method therefor, and surface light source device provided with it
KR100798680B1 (en) * 2005-11-10 2008-01-28 오완호 The luminous device using light emitting diodes
US7527411B2 (en) 2006-02-22 2009-05-05 Citizen Electronics Co., Ltd. Lightguide plate of a double-sided illumination backlight and a double-sided liquid crystal display unit using the backlight
JP2008004948A (en) * 2006-06-09 2008-01-10 Philips Lumileds Lightng Co Llc Low profile side emitting led
CN102086995A (en) * 2009-12-08 2011-06-08 乐金显示有限公司 Backlight unit and liquid crystal display device having the same
US8508693B2 (en) 2009-12-08 2013-08-13 Lg Display Co., Ltd. Backlight unit and liquid crystal display device having the same
WO2012050121A1 (en) * 2010-10-15 2012-04-19 シャープ株式会社 Backlight unit
AU2011314771B2 (en) * 2010-10-15 2014-08-28 Sharp Kabushiki Kaisha Backlight unit

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