KR20080101943A - Light guide film for keypad - Google Patents

Abstract

A light guide plate for a keypad for increasing and uniformly distributing the light of a light emitting diode is provided to increase and distribute the light of the light emitting diode by gradually controlling the luminance of each key unit by sequentially controlling the depth and interval of number and figure by a CNC process. A light guide plate(30) forms a pattern in a precut method on a flexible polycarbonate sheet of 0.125m/m. A lighting optical sheet for a keypad changes the LED light source into a distant light source. A number and a practical figure are successively molded on the left and right downside of the precut piping section. The light emitting diode light is uniformly induced at the processing pattern(31~37) without shadow.

Description

Light guide plate for keypad {LIGHT GUIDE FILM FOR KEYPAD}

1 is a plan view showing a light guide plate for a keypad according to an embodiment of the present invention;

2 is a vertical cross-sectional view for explaining a light guide plate for a keypad of the present invention;

Figure 3 is a state diagram radiated from the characters and figures of the processing pattern in the light guide plate for the keypad of the present invention,

4 is a state diagram in which light of the light emitting diode is emitted from the light guide plate for keypad of the present invention;

5 is a plan view showing a light guide plate for a keypad according to another embodiment of the present invention;

6 is a plan view showing a light guide plate for a conventional keypad;

7 and 8 are views showing a state of processing a light guide plate for a conventional keypad and a radiation state in a groove.

※ Explanation of code about main part of drawing ※

10: light guide plate 20: mold

30, 30 ': light guide plate

31-37: Machining pattern 38, 39, 39 ': Upper groove

The present invention sequentially adjusts the brightness and brightness of each key portion by sequentially adjusting and arranging the numbers and figures for each processing pattern by CNC (Computer Numerical Control) machining, thereby not only increasing the light of the light emitting diode as a whole but increasing uniformity. It relates to a light guide plate for a keypad to be distributed.

In general, the keypad is used as a switch device for generating signals and performing various additional functions by using a communication device such as a mobile phone. Such a switch has a key printed with numbers or letters. The key is inserted into a hole provided in the front housing of the communication device, and a part of the key protrudes out of the front housing.

The key constituting the keypad is formed with a printed surface on which numbers or letters are displayed as described above, and checks the numbers or letters displayed on the printed surface and presses a key desired by the user. In addition, a light source including a light emitting diode is installed outside the bottom of the key so that the printing surface can be checked at night. When the light is irradiated from the light source, the user may recognize numbers or letters printed on each key due to a backlighting effect. It is configured to be.

FIG. 6 is a plan view illustrating a conventional light guide plate for a keypad, and a plurality of grooves 12 and 12 are arranged on the bottom surface of the light guide plate 10, and the light emitting diode light of the upper portion (not shown) is provided in the grooves (not shown). 12, 12-) it radiates brightly and gradually decreases.

7 and 8 are views showing a state of processing a light guide plate for a conventional keypad and a radiation state in a groove. That is, the conventional heat press method is a method of processing the pattern of the groove into a mold (CORE: 20) and stamped on the light guide plate 10 as shown in Figure 7, wherein the shape of the pattern is extruded with stone or sandpaper, for example It is appearing as if it is. Therefore, when the grooves 12 and 12 of the light guide plate 10 are worked by using a conventional heat press method, since the work is performed using high temperature and high pressure even if the mold technology is good, as shown in FIG. 8. The processing surface of the groove could not be good, there was a disadvantage that the reflection of light is not good.

As shown in FIG. 6, the intensity of the light toward the rear is weakened, and the shadow outside the angle of the light occurs, and it is difficult to cope with frequent modification and sample request by the mold method. Therefore, the conventional heat press method is difficult to modify again when the uniform groove 12 is processed in one mold 10, it is difficult to modify later if the depth of the groove 12 is not set well from the beginning of the operator The problem of becoming difficult has arisen.

Therefore, the conventional heat press method, as well as environmental problems in manufacturing, the deformation of the light guide plate material occurs as time passes and the deformation becomes more severe, and it is easy to see that the depth adjustment of the unevenness is limited by the press method. have.

The present invention has been invented by adopting a good machined groove surface in order to solve the problems of the conventional heat press as described above, by adjusting the spacing and depth of numbers and figures for each processing pattern by CNC machining with dot density The light guide plate for the keypad of the FLGF (FREE-CUT KEYPAD LIGHTING GUIDE FILM) is improved to be uniformly distributed as well as to diffuse the light of the light emitting diode as a whole by adjusting the brightness to the brightness of each key part. There is a purpose.

Another object of the present invention, since the actual processing for each processing pattern of each character and figure, the brightness of each key is high, the uniformity of the light is also good, by forming each pattern to prevent light leakage of the edge area to the light to the shadowed area It is possible to induce and do not have a thermal or chemical process can provide an economic light guide plate for the keypad without deformation of the polycarbonate sheet.

In order to achieve the above object, the present invention provides a light guide plate which is directed straight or left and right from a side view light emitting diode to form a pre-cut pattern on a flashable polycarbonate sheet of 0.125 m / m in FLGF. A lighting optical sheet for keypad for converting the light source into a distant light source; As the grooves are gradually deepened from the top to the bottom, the actual numbers and figures of precut processing patterns, which are sequentially formed from the left and right sides of the precut piping part, use precut piping, and the light emitting diode light in the upper groove is recalled. It is characterized by including the one that is uniformly induced for each processing pattern and lightened without a shaded part.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a plan view showing a light guide plate for a keypad according to an embodiment of the present invention, in which the distance and depth of numbers and figures in the machining patterns 31 to 37 by CNC machining are different in dot (scratch: SCRETCH) density. By arranging them in order, the light of the light emitting diode (LED: not shown) can be brightly adjusted according to the brightness of each key part (CLR, SEND, END, 1 2 3 4 5 6 7 8 9 * 0 #). The light guide plate 30 for the keypad of the FLGF (FREE-CUT KEYPAD LIGHTING GUIDE FILM) improved not only to increase the overall diffusion but uniformly distributed.

The light guide plate 30, which is projected straight or left and right from the side view light emitting diodes (LEDs) in the upper grooves 38 and 39, is formed of a precut pattern on a flashable polycarbonate sheet of 0.125 m / m. The optical sheet for keypad lighting converts a point (LED) light source into a distant light source. Therefore, the present invention is capable of producing small quantities of various kinds, sample response in a short period of time, low production cost, and can use environmentally friendly materials.

As shown in FIG. 2 at the light emitting diode (LED) position of the light guide plate 30, the light may be brightened by adjusting the precut depth and the pattern spacing as the distance from the upper part to the lower part. That is, the pre-cut piping portion 31 is formed in the upper grooves 38 and 39 of the light guide plate 30, and the free-cut piping portion 31 is formed on the left and right sides in order. The processing patterns 32-37 of numbers and figures can be made uniformly bright by using precut piping and inducing light. Therefore, in the precut pattern of machining, scattered light is generated by the total reflection of the light.

In the FLGF light guide plate, the shape of the pre-cut processing pattern uses actual figures or numbers. In the step-by-step process of CNC machining equipment, the machine origin is set and the light guide plate, which is an optical sheet, is set not to be twisted. Then enter the program and then perform the machining.

The order in which the light guide plate is processed is to design a pattern in consideration of the position shown in the keypad drawing, and to set it in the robot machine using the drawing thus designed. The robot machine is used to directly process the light guide plate, and a half knife operation is performed by the processed semi-finished press. Then, the light guide plate of the precut processing pattern is assembled to the metal dome and then measured for conformity measurement.

In the characteristic which shows the comparative data of the brightness (cd m <2>) with respect to the light-guide plate for keypads of this invention, the color red which can be easily distinguished by an operator is luminance 131-168, dark yellow is luminance 111-130, and bright yellow is luminance 91-110, green is luminance 71-90, light blue is luminance 51-70, and pale blue is luminance 0-50.

Therefore, the luminances (cd m 2) of the numbers 1-9, * 0 # of the precut processing patterns 34-37 are 139, 168, 90, 132, 91, 69, 82.1, 83.7, 85.2, 102, 99.1, 130 The average luminance is 105.93 and the deviation is 41.1%, whereas the conventional luminance is 77.9, 92.3, 122, 59.1, 86.7, 115, 58.8, 68.4, 93.1, 59.4, 65.3, 53.4, which is a deviation of 43.8% from the average of 79.28. Thus, the operator can distinguish between red 1 2 4 and green 3 5 6 7 8 9, and bright yellow * 0 and dark yellow #.

Here, the luminance measurement is measured with the keypad mounted, the amount of light is different by the number of the keypad, there is a possibility of error occurs by the assembly of the light guide plate and the keypad. The precut machining patterns 32 and 33 of letters and figures between the machining pattern 31 and the other machining patterns 34 may be machined and arranged in the same manner as above.

As described above, in the present invention, since the brightness of the precut processing patterns 31 to 37 can be adjusted in the design of the actual letters and figures on the light guide plate 30, the parts can be modified according to the CNC machining. It is supposed to be. The figures 1-9 and * 0 # of the precut processing patterns 34 to 37 may be formed with various shapes, respectively, to adjust luminance.

2 is a vertical cross-sectional view for explaining a light guide plate for a keypad of the present invention, Figure 4 is a state diagram in which the light of the light emitting diode is emitted in the light guide plate for the keypad of the present invention.

 That is, as shown in FIG. 2, the grooves gradually become deeper, and thus the actual number and figure processing patterns 32 to 37 formed sequentially from the left and right sides in the precut piping 31 use precut piping. As a result, the LED light in the upper grooves 38 and 39 may be uniformly induced to brighten the whole (see FIG. 4).

Therefore, since the FLGF light guide plate 30 of the present invention processes the actual number and figure processing patterns 31 to 37 directly on the surface directly, the depth is easily modified. Therefore, the present invention has the advantage that mass production is possible within a short time before the development of the light guide plate for the keypad.

Figure 3 is a state diagram radiated from the characters and figures of the processing pattern in the light guide plate for the keypad of the present invention, because the FLGF light guide plate of the present invention is machined directly on the surface, unlike the conventional process pattern 31-37 as a whole of the groove The machining surface is good. Accordingly, the present invention manufactured by machining enables individual brightness adjustment of keys by simple physical lighting by machining and uniformly adjusts the brightness of the beginning and the end of the light emitting diode.

On the other hand, the light guide plate for the keypad of the present invention can be used in a state integrating the metal dome and then combined with the PC. The FLGF light guide plate of the present invention has a difference in the erection of each key according to the deviation of the assembly of the light emitting diodes. There is an advantage you can expect.

As described above, the present invention is less constrained to send light to the tail regardless of the dot (scratch) area by the precut pattern method (see FIGS. 2 and 4). Places outside the angle of light to solve the shadow by dragging the light using the piping. In addition, frequent modifications and sample response are advantageous in the machining method using a precut robot. Therefore, the ability to adjust the brightness of the actual individual characters is most advantageous to increase the overall uniformity of the keypad.

FIG. 5 is a plan view illustrating a light guide plate for a keypad according to another embodiment of the present invention, and the light guide plate 30 'for the keypad of the present invention is different from the light guide plate 30 shown in FIG. 39 is formed as a whole with grooves 39 'having unevenness, and is configured to further improve the luminance of the light emitting diode portion radiated as shown from the unevenness of the groove 39'.

As described above, according to the present invention, since each machining pattern of each character and figure is machined, the brightness of each key is high, the uniformity of light is good, and each pattern is formed so that the light leakage of the edge part can be prevented and the shaded part is formed. It can induce light and has no thermal or chemical process, thus providing an economical light guide plate for FLGF's keypad without deformation of polycarbonate sheet.

Although described based on the light guide plate for keypad of this invention, this is illustrative of the best embodiment of this invention, and does not limit the claim of this invention. It will be apparent to those skilled in the art that various modifications and imitations can be made without departing from the scope of the technical idea of the present invention.

Claims (4)

The light guide plate, which is projected straight or left and right from the side view LED, forms a pre-cut pattern on a flashable polycarbonate sheet of 0.125 m / m with FLGF, thereby converting the point (LED) light source into a distant light source. With sheets; The grooves are gradually deepened from the top to the bottom, and the precut machining patterns of actual numbers and figures, which are sequentially formed in the left and right bottoms in the precut piping, use precut piping and process the light emitting diode light in the upper groove. Light guide plate for a keypad, characterized in that it comprises a uniform induction for each pattern to be bright without a shadow area. The method of claim 1, The light guide plate for the keypad, characterized in that the figures 1 to 9, * 0 # of the pre-cut processing patterns are formed in the shape of each side to adjust the brightness for each key. The method according to claim 1 or 2, The light guide plate is a light guide plate for a keypad, characterized in that further comprising the one used in combination with the metal dome combined with the PCB. The method of claim 1, Light guide plate for a keypad, characterized in that the brightness is further increased by forming the upper groove as a groove having an unevenness as a whole.

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