KR100947356B1 - Apparatus and method for manufacturing light guide plate - Google Patents

Abstract

PURPOSE: An apparatus and a method for manufacturing light guide panels are provided to improve the productivity per unit time by simultaneously processing two light guide panels. CONSTITUTION: A plurality of light guide panels is loaded on the upper side of a transfer stage(120). The transfer stage is transferred to the direction of the long side of the short side of the light guide panels. A common laser head(130) is transmitted a laser form a laser source. The common laser head forms patterns on the surface of the light guide panels. The transfer stage is a dual stage which includes a first and a second light guide panel loading parts. A control part controls the common laser head to form via patterns with different lengths.

Description

Light guide plate manufacturing apparatus and manufacturing method {Apparatus and method for manufacturing light guide plate}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light guide plate manufacturing apparatus and a manufacturing method, and more particularly, to a light guide plate manufacturing apparatus and a manufacturing method which can improve productivity per unit time while being able to form a uniform pattern on the light guide plate.

A light guide plate is a component that performs brightness and uniform illumination functions in a back light unit.

That is, the light guide plate refers to acrylic assembled in a backlight unit that guides light to a liquid crystal (LCD panel) in a liquid crystal display (LCD). It is a kind of plastic molded lens that plays a role of uniformly transmitting the entire LCD panel.

As described above, the light guide plate must uniformly transmit the light emitted from the illumination to the entire surface of the LCD panel, so that a pattern is formed on the surface thereof. The pattern may have various shapes such as a prism pattern, a checkerboard pattern, a polygonal pattern, a star pattern, a dot pattern, a bar pattern, and the like.

Among these patterns, a prism pattern, a checkerboard pattern, a polygonal pattern, a star pattern, and the like are insufficient to be applied to a large television because of difficulty in controlling luminance. Therefore, a dot pattern or a bar pattern is usually applied to a light guide plate applied to a large television, for example, a large television of about 50 inches.

On the other hand, in forming a dot pattern or a bar pattern on the surface of the light guide plate, a pressing method using a mold may be considered. However, the method using a mold has difficulty in manufacturing a mold and also provides a uniform pattern on the surface of the light guide plate. It is not easy to apply because it cannot be formed consistently and precisely. Therefore, the research and development of the light guide plate manufacturing apparatus using a laser is progressing in order to improve the precision of processing in the recent years.

Hereinafter, a light guide plate manufacturing apparatus for forming a bar pattern on the surface of the light guide plate using a laser will be described.

In the conventional light guide plate manufacturing apparatus, the light guide plate is also fixed by mounting the light guide plate on one fixed stage, and then the bar head is formed on the surface of the light guide plate while the laser head is moved in the X and Y axes with respect to the fixed light guide plate. It has a structure to let For reference, the X axis may be a long side direction of the light guide plate, and the Y axis may be a short side direction of the light guide plate.

By the way, in such a conventional light guide plate manufacturing apparatus, since the laser head is moved in the X-axis and Y-axis with respect to the fixed stage, the pattern is formed on the surface of the light guide plate which is fixed on the fixed stage. As the laser head is moved in the direction, the distance from the laser source to the laser head is changed, so that the amount of laser light provided from the laser source to the laser head is not constant, making it difficult to form a uniform pattern.

In addition, the conventional light guide plate manufacturing apparatus has a structure in which a single light guide plate can be manufactured in one light guide plate manufacturing apparatus, and thus there is a problem in that productivity per unit time is reduced due to the acceleration and deceleration time of the laser head.

An object of the present invention is to provide a light guide plate manufacturing apparatus and a manufacturing method which can improve the productivity per unit time while being able to form a uniform pattern on the light guide plate.

According to the present invention, a plurality of light guide plate is loaded on the upper surface, the movable stage movable in the long side or short side direction of the light guide plate; And a common laser head which receives a laser provided from a laser source, forms a predetermined pattern on the surface of the plurality of light guide plates loaded on the moving stage, and is commonly applied to the plurality of light guide plates. It is achieved by the light-guide plate manufacturing apparatus made into.

The movement stage may be a dual movement stage provided with first and second light guide plate loading parts on which two light guide plates are loaded.

The common laser head is reciprocally driven in a direction intersecting with a direction in which the moving stage moves, so that a bar pattern having different first and second lengths is formed on the first and second light guide plates, respectively. It may further include a control unit for controlling the head.

The controller may control the common laser head so that the first and second lengths are set based on an average output of the laser beams irradiated from the common laser head to the first and second light guide plates.

When the common laser head reaches a shorter distance from the laser source to the common laser head when positioned in the second light guide plate than when the common laser head is located in the first light guide plate, the controller is further configured to provide the The common laser head can be controlled such that the bar pattern of the second length is shorter.

The display device may further include an alignment unit provided on an upper surface of the moving stage to align loading positions of the plurality of light guide plates.

The alignment unit may include at least one reference alignment rib formed on an upper surface of the moving stage and close to one side walls of the plurality of light guide plates to form a reference of a loading position for the plurality of light guide plates.

The alignment portion is disposed in a direction crossing with respect to the reference alignment rib between the plurality of light guide plates loaded on the moving stage, and the other side walls of the plurality of light guide plates are closely contacted with the reference alignment ribs. A side alignment alignment rib for aligning the light guide plate may be further included.

The moving stage may be a dual moving stage provided with first and second light guide plate loading parts in which two light guide plates are loaded on an upper surface thereof, and the side alignment alignment ribs may be disposed between the first and second light guide plates. And a common side alignment align rib arranged to align the first and second light guide plates, wherein the alignment unit presses the plurality of light guide plates toward the reference align rib from the opposite side of the reference align rib. The light guide plate may further include a movable pressure pad for preventing the position movement of the light guide plate.

A base plate provided in a lower region of the movement stage to support the movement stage in a Y-axis direction, which is a short side direction of the light guide plate; And a stage moving part provided on the moving stage and the base plate to move the moving stage in the Y-axis direction with respect to the base plate.

The stage moving unit includes: a moving unit coupled to the moving stage and the base plate to move the moving stage in the Y-axis direction; And a sensing unit configured to detect a moving distance of the mobile unit in stages and transmit a sensing signal to the controller.

The mobile unit may be a linear motor, and a lower part of the moving stage may further include a display unit that is detected by the sensing unit and displays a moving distance of the mobile unit.

The stage moving unit may further include a pair of guides provided on both sides of the mobile unit to be symmetrical to guide the movement of the moving stage.

Each of the pair of guides may include: a rail block coupled to any one of the moving stage and the base plate; And a rail coupled to the other of the movable stage and the base plate and slidably engaged with the rail block in a dove tail shape.

At least one shock absorber provided on the base plate to prevent excessive forward or backward movement of the moving stage; And a sober bracket provided in the movable stage to selectively contact the shock absorber.

The moving stage may include a plurality of vacuum suction holes for sucking the plurality of light guide plates in a vacuum; And a plurality of weight reducing grooves recessed between the plurality of vacuum suction holes to reduce the weight of the moving stage.

On the other hand, the above object, according to the present invention, forming a bar pattern (bar pattern) having a first length using a common laser head on the first light guide plate seated on one side on the moving stage; And forming a bar pattern having a second length different from the first length by using the common laser head on a second light guide plate disposed side by side with the first light guide plate on the other side of the moving stage. It is also achieved by a light guide plate manufacturing method.

Here, the first length and the second length are based on the average output of the laser beam irradiated to the first light guide plate from the common laser head and the average output of the laser beam irradiated to the second light guide plate from the common laser head. Can be set.

According to the present invention, it is possible to form a uniform pattern on the light guide plate while improving productivity per unit time.

In order to fully understand the present invention, the operational advantages of the present invention, and the objects achieved by the practice of the present invention, reference should be made to the accompanying drawings which illustrate preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, the present invention will be described in detail by explaining preferred embodiments of the present invention with reference to the accompanying drawings. Like reference numerals in the drawings denote like elements.

1 is a schematic plan view of a light guide plate manufactured by a light guide plate manufacturing apparatus according to a first embodiment of the present invention.

As shown in this figure, the light guide plate 1, which is made of a substantially rectangular plate-like body, is a component assembled in a backlight unit that guides light to a liquid crystal (LCD panel) in a liquid crystal display (LCD) as described above. to be.

The light guide plate 1 may be made of extruded plate acrylic or cast acrylic, and a plurality of LED coupling parts 3 are formed on the circumferential surface thereof, to which a plurality of LEDs (LEDs) are coupled. A plurality of patterns 2 are formed on the surface of the light guide plate 1 as a means for uniformly diffusing light from the LEDs in the entire region of the light guide plate 1.

In the present embodiment, the pattern 2 formed on the light guide plate 1 is formed in a bar pattern by a laser, in particular a carbon dioxide gas laser. The bar pattern is advantageous for brightness control and is sufficient for large televisions that require sharper and clearer displays, such as large televisions of around 50 inches.

However, since the scope of the present invention does not need to be limited thereto, the shape of the pattern 2 may be a dot pattern. In addition, the type of laser that processes the pattern 2 may also be applied to the laser of other physical properties other than the carbon dioxide laser.

Referring to FIGS. 2 to 9, a light guide plate manufacturing apparatus for manufacturing a light guide plate 1 having a bar pattern 2 formed on its surface as shown in FIG. 1 is as follows.

2 is a perspective view of a light guide plate manufacturing apparatus according to a first embodiment of the present invention, Figure 3 is a partial cutaway perspective view of Figure 2, Figure 4 is a front view of Figure 2, Figure 5 is an enlarged perspective view of the main portion of the belt, 6 is a partial plan view of FIG. 2 showing the arrangement relationship of the common laser head, the moving stage and the light guide plate, FIG. 7 is a graph schematically showing the output characteristics of the carbon dioxide gas laser, and FIGS. 8 and 9 are respectively shown in FIG. It is a perspective view showing the process of manufacturing the light guide plate by the light guide plate manufacturing apparatus step by step.

As shown in these figures, the light guide plate manufacturing apparatus of this embodiment is loaded with the apparatus main body 110 and two first and second light guide plates 1a, 1b, FIGS. 6, 8 and 9 on the upper surface. And the bar patterns 2a, 2b and 6 on the surfaces of the movable stage 120 and the first and second light guide plates 1a and 1b loaded on the movable stage 120, which are movable in the Y-axis direction of FIG. 2. ) And a single common laser head 130 commonly applied to the first and second light guide plates 1a and 1b.

The device body 110 is a portion for supporting the rest of the configuration except the movement stage 120 and the base plate 140.

The device body 110 is arranged to stand in the direction crossed with respect to the base plate 140. Most of the device body 110 is made of a metal material similar to the base plate 140, but may be used in part stone (石) material. The apparatus main body 110 is further provided with a dust inhaler 112 for sucking dust generated when the pattern (2a, 2b) processing.

The movement stage 120 is a portion in which the light guide plates 1a and 1b are loaded. Since the first and second light guide plates 1a and 1b are loaded on the moving stage 120 of the present exemplary embodiment, the moving stage 120 is applied as a dual moving stage.

However, since the scope of the present invention does not need to be limited thereto, three or more light guide plates 1 (refer to FIG. 1) may be loaded on the upper surface of the moving stage 120. However, when the pattern 2 (see FIG. 1) forming operation is performed by the laser after three or more light guide plates 1 are loaded on the upper surface of the moving stage 120, it is difficult to constantly control the amount of light of the laser. It may be difficult to form a uniform pattern 2 on all three or more light guide plates 1.

Therefore, if the light guide plate 1 is applied to a large television of about 50 inches, as shown in this embodiment, two first and second light guide plates 1a and 1b on the upper surface of the moving stage 120, Figs. 9) may be advantageously loaded. However, the scope of the present invention need not be limited thereto. In fact, it has been experimented that productivity is increased by 30% or more when the pattern 2a and 2b forming operations are simultaneously performed on the two first and second light guide plates 1a and 1b.

On the upper surface of the moving stage 120, two first and second LGP loading parts 121a and 121b are provided, in which two first and second LGPs 1a and 1b are loaded, respectively. The first and second LGP loading parts 121a and 121b may be provided in the form of two areas on the upper surface of the moving stage 120 processed in the shape of one disc as in the present embodiment, or One may be provided in two separate stages (not shown) separately.

On the surface of the moving stage 120, a plurality of vacuum adsorption holes 122 for adsorbing the first and second light guide plates 121a and 121b by vacuum so as not to shake the first and second light guide plates 1a and 1b. Is provided.

In addition, a plurality of weight reducing grooves 123 are formed between the vacuum suction holes 122 to be recessed from the surface of the moving stage 120.

The weight reducing groove 123 reduces the overall weight of the moving stage 120 made of a metal material to reduce the manufacturing cost of the moving stage 120 while reducing the power consumption of the moving stage 120. It plays a role.

For example, in order to load two light guide plates 1a and 1b of approximately 50 inches on the moving stage 120, the size of the moving stage 120 must be large, in this case, the weight of the moving stage 120. Various problems may occur according to the present invention. However, when the groove for reducing weight 123 is formed on the surface of the moving stage 120 as in the present embodiment, it is sufficient to solve various problems due to high weight.

An alignment part 124 is provided on the upper surface of the moving stage 120 to align the loading positions of the first and second light guide plates 1a and 1b when the first and second light guide plates 1a and 1b are loaded.

The alignment unit 124 is provided with a plurality of reference alignment ribs 124a provided in the front portion of the movement stage 120 along the Y-axis direction, and a side provided in the center portion of the movement stage 120 in parallel with the Y-axis direction. The alignment rib 124b and the movable pressure pad 124c are provided.

The reference alignment rib 124a forms a reference of the loading position with respect to the first and second light guide plates 1a and 1b while the front side walls of the first and second light guide plates 1a and 1b are in close contact with each other along the Y axis direction. .

The side alignment alignment ribs 124b align the first and second light guide plates 1a and 1b together with the reference alignment ribs 124a while the left and right side walls of the first and second light guide plates 1a and 1b are in close contact with each other. It plays a role. As described above, the side alignment alignment ribs 124b are disposed in a direction crossing with respect to the reference alignment rib 124a and are disposed in an area between the first and second light guide plate loading parts 121a and 121b. .

The side alignment aligning ribs 124b form a dummy space between the first and second light guide plates 1a and 1b in addition to aligning the first and second light guide plates 1a and 1b. It also serves as a tolerance management role for the first and second light guide plates 1a and 1b.

That is, even if the light guide plate 1 (refer to FIG. 1) is precisely processed, since the processing tolerance exists for each of the light guide plates 1, the size of the light guide plates 1 may not be the same. Therefore, if the two first and second light guide plates 1a and 1b are brought into contact with each other side by side without side alignment ribs 124b and loaded on the moving stage 120, the patterns 2a and 2b are processed. When the two first and second LGPs 1a and 1b are different in size, it may be difficult for the common laser head 130 to reciprocate a predetermined distance to form uniform patterns 2a and 2b. . However, when the side alignment alignment ribs 124b are provided as in this embodiment, the side alignment alignment ribs 124b having different sizes based on the sizes of the first and second light guide plates 1a and 1b to be loaded. May be sufficient to form a uniform pattern (2a, 2b).

The alignment rib 124b for side alignment is disposed between the first and second light guide plates 1a and 1b to align both the first and second light guide plates 1a and 1b. In this case, since the first and second light guide plates 1a and 1b may be centrally arranged and arranged, productivity may be further improved.

The movable pressure pad 124c presses the first and second light guide plates 1a and 1b toward the reference alignment rib 124a on the opposite side of the reference alignment rib 124a to thereby first and second light guide plates 1a and 1b. This serves to prevent the arbitrarily shifted position.

Unlike the reference alignment rib 124a and the side alignment alignment rib 124b, the movable pressure pad 124c may be detachably provided on the moving stage 120. Considering that the movement stage 120 is made of a metal material, the movable pressure pad 124c may be simply provided with a magnet.

Accordingly, the first and second light guide plates 1a and 1b to be processed are brought into close contact with the reference alignment rib 124a and the left and right walls are in close contact with the side alignment alignment rib 124b. Loading position with respect to the first and second light guide plates 1a and 1b by simply pressing the rear side walls of the first and second light guide plates 1a and 1b toward the reference alignment rib 124a using the pressure pad 124c. You can align the.

On the other hand, a base plate 140 is provided in the lower region of the movable stage 120 to support the movable stage 120 to be movable in the Y-axis direction. The base plate 140 may be connected to the apparatus body 110 described above.

A stage moving part 150 is provided in the base plate 140 and the moving stage 120 to move the moving stage 120 in the Y-axis direction with respect to the fixed base plate 140.

As shown in FIG. 4, the stage moving unit 150 is coupled to the moving stage 120 and the base plate 140 to move the moving stage 120 in the Y-axis direction, and to move. The detector 152 transmits a detection signal for detecting the moving distance of the unit 151 step by step to the controller. In addition to the mobile unit 151, the control unit controls the first half of the apparatus, in particular the common laser head 130, the control method of the common laser head 130 by the control unit will be described later.

The moving unit 151 may be applied as a linear motor that is easy to control position. A display unit (not shown) that is detected by the sensing unit 152 but displays the moving distance of the mobile unit 151 may be further formed below the moving stage 120. The display unit may be a plurality of grid lines formed under the moving stage 120 along the Y-axis direction.

In addition to this, the stage moving unit 150 is further provided with a pair of guides 154 provided on both sides of the moving unit 151 to guide the movement of the moving stage 120.

Each of the pair of guides 154 is coupled to the rail block 154a coupled to the base plate 140, and is coupled to the movable stage 120, and slidably moves in the shape of the rail block 154a and the dove tail. It may include an interlocking rail 154b. Of course, the rail block 154a may be provided in the movable stage 120 and the rail 154b may be provided in the base plate 140.

As described above, since the moving stage 120 made of metal is a huge structure, the light guide plate 1 (see FIG. 1) is damaged if the moving stage 120 is excessively or suddenly retracted due to an abnormal cause. Of course, this can pose a threat to worker safety.

To prevent this, the base plate 140 is provided with a shock absorber 143 (shock absorber (see FIG. 9)) as a means for preventing excessive forward or backward movement of the moving stage 120. The shock absorbers 143 may be provided in two pairs on both front and rear sides of the mobile unit 151.

The shock absorber 143 includes an oil shock absorber and a gas shock absorber, but any of them may be applied. In the present embodiment, a gas shock absorber is applied in which a spring (not shown) expands in the opposite direction while absorbing excessive shock by filling oil and nitrogen gas in the cylinder.

In order to operate the shock absorber 143, the move stage 120 is provided with a sober bracket 125 that is in selective contact with the shock absorber 143. In general, the absorber bracket 125 is not in contact with the shock absorber 143, but the absorber bracket 125 is in contact with the shock absorber 143 when the moving stage 120 is excessively moved forward or backward by abnormal operation. It prevents excessive forward or backward movement of the moving stage 120.

Meanwhile, the common laser head 130 receives the laser provided from the laser source L / S (refer to FIG. 6), and the first and second light guide plates loaded on the moving stage 120 while being reciprocally driven in the X-axis direction. It serves to form bar patterns 2a and 2b on the surfaces of (1a and 1b).

In the present exemplary embodiment, two first and second light guide plates 1a and 1b are loaded on one moving stage 120, but one common laser head 130 is used for the first and second light guide plates 1a and 1b. Bar patterns 2a and 2b are formed in both.

As such, when the bar patterns 2a and 2b are formed on the surfaces of the two first and second light guide plates 1a and 1b by using one common laser head 130, the cost of the two laser heads may be reduced. In addition to reducing the pressure, the structure is simplified.

The laser provided to the common laser head 130 is a carbon dioxide gas laser provided from a laser source (L / S) (see FIG. 6) provided in the sober bracket 111 provided on the upper portion of the apparatus body 110. Since the laser cannot be provided directly from the laser source L / S to the common laser head 130, a plurality of mirrors for converting the direction of the laser beam between the laser source L / S and the common laser head 130 ( Mirror).

In order to form the bar patterns 2a and 2b on the surfaces of the first and second light guide plates 1a and 1b while the common laser head 130 reciprocates along the X-axis direction, the common laser head 130 is moved to X. A head driver 160 for reciprocating in the axial direction is provided.

Referring to FIGS. 5 and 6, the head driving unit 160 may include a motor 161 generating a driving force, a driving pulley 162 coupled to a rotation shaft of the motor 161, and an opposite side of the driving pulley 162. A driven pulley 163 is provided, and a belt 164 that supports the common laser head 130 and is wound around the driving pulley 162 and the driven pulley 163 in the form of a closed loop. As in the present embodiment, when the common laser head 130 is reciprocally driven by the belt 164, the wear and friction of the common laser head 130 and the belt 164 may be prevented from increasing.

Since the common laser head 130 supported by the belt 164 needs to reciprocately drive, the motor 161 is applied as a servo motor capable of controlling rotation and speed in the forward and reverse directions. The belt 164 is applied as a timing belt made of engineering plastic material having wear resistance.

At this time, the belt 164 is applied to the vertical belt 164 disposed vertically in this embodiment, such that the surface of the belt 164 intersects the ground as shown in FIG. When applied to the vertical belt 164 as described above, the rotational track of the belt 164 is not visible from the outside of the device as shown in Figure 2 has the advantage that the appearance is neat and compact. However, since the scope of the present invention does not need to be limited thereto, the belt 164 may be a horizontal belt (not shown) in which a rotational trajectory, that is, an oval-shaped rotational trajectory is formed in the vertical direction.

As in the present embodiment, when the vertical belt 164 is applied and the common laser head 130 is reciprocally driven while the vertical belt 164 rotates at high speed by the motor 161, the driven pulley 163 is driven. When the vertical belt 164 and the vertical belt 164 is in contact with each other due to the deflection of the vertical belt 164 is subjected to different repetitive loads, thereby the upper end of the driven pulley 163 in contact with the vertical belt 164 Can be broken.

In order to prevent this, when the belt is applied to the vertical belt 164 as in the present embodiment, a belt support roller 170 is provided in the adjacent region of the driven pulley 163 to prevent the sagging of the vertical belt 164. .

The belt support roller 170 is in contact with the rotatable relative to prevent the sag of the belt 164, further serves to prevent the driven pulley 163 from being damaged.

The belt support roller 170 is a free-rotating roller and is disposed on both sides of the belt 164 with the belt 164 interposed therebetween to prevent sagging of the belt 164. The belt support roller 170 may be disposed on both sides of the vertical belt 164 adjacent to the driven pulley 163, but may also be disposed on the driving pulley 162 in some cases.

Meanwhile, referring to FIG. 6, the bar patterns 2a and 2b are formed on the surfaces of the first and second light guide plates 1a and 1b using the common laser head 130.

Referring to FIG. 6, the common laser head 130 controlled by the controller (not shown) reciprocates a distance greater than the full width (full length) of the two first and second light guide plates 1a and 1b. This is because the speed of each section of the common laser head 130 reciprocatingly driven at a high speed of approximately 4000 to 5000 mm / s is not constant, and also the output characteristics of the laser beam (including the intensity of the laser beam) are not constant. Because.

In particular, the laser beam output when the common laser head 130 is located in the constant velocity section in this embodiment because the output characteristics of the laser beam is not even more constant in the acceleration / deceleration section in the graph of the lower region shown in FIG. The bar patterns 2a and 2b are formed on the first and second light guide plates 1a and 1b by using.

However, even in the constant velocity section illustrated in FIG. 6, the output characteristics of the laser beam may not be considered to be exactly the same at all points of the constant velocity section. In particular, in the case of processing the bar patterns 2a and 2b by arranging two large area first and second light guide plates 1a and 1b as in the present embodiment, the common laser head 130 may use the first light guide plate 1a. Proper control of the laser beam output characteristics (intensity) when passing through) and the laser beam output characteristics (intensity) when the common laser head 130 passes through the second light guide plate 1b may be different from each other. Is required.

For convenience of description, the lengths of the bar patterns 2a and 2b formed on the first and second light guide plates 1a and 1b are referred to as L1 and L2 which are the first lengths, respectively, and the bar patterns 2a, The pitch between 2b) is P1 and P2, respectively, and the space | interval between the bar patterns 2a and 2b along the Y-axis direction is called W1 and W2, respectively.

L1 = L2, P1 assuming that the output characteristics of the laser beam from the common laser head 130 for laser processing while reciprocally driving the two first and second light guide plates 1a and 1b are at least as constant as in the constant velocity section. = P2, W1 = W2.

However, as described above, since the two large-area light guide plates 1a and 1b are used and the moving distance of the common laser head 130 is long, the laser reaching the common laser head 130 from the laser source L / S The reach of the beam is different in the first light guide plate 1a and the second light guide plate 1b. That is, the output characteristics (intensity) of the laser beam when the common laser head 130 processes the first bar pattern 2a in the first light guide plate 1a, and the common laser head 130 is the second light guide plate 1b. The first and second bar patterns 2a and 2b are different in depth because the output characteristics (intensities) of the laser beam when processing the second bar pattern 2b are different. Therefore, L1 = L2, P1 = P2, W1 = W2, in particular, the length L1 of the first bar pattern 2a and the length L2 of the second bar pattern 2b formed on the first and second light guide plates 1a and 1b. Is not the same, and if it is not properly compensated for, one of the first and second LGPs 1a and 1b may cause a pattern defect.

Therefore, in the present embodiment, the control unit uses the common laser head such that the bar patterns 2a, 2b and bar patterns having different first and second lengths L1 and L2 are formed on the first and second light guide plates 1a and 1b, respectively. 130 is controlled.

That is, the control unit of the present embodiment is shared so that the first and second lengths L1 and L2 are set based on the average output of the laser beams irradiated from the common laser head 130 to the first and second light guide plates 1a and 1b. The laser head 130 is controlled.

For example, as in the present embodiment, the common laser head 130 from the laser source L / S when the common laser head 130 is positioned on the second light guide plate 1b than when it is positioned on the first light guide plate 1a. When the distance of the laser beam reached is shorter, the control unit controls the common laser head 130 so that the length L2 of the second bar pattern 2b is shorter than the length L1 of the first bar pattern 2a. do.

In other words, when the common laser head 130 passes the second light guide plate 1b, since the laser beam is strong, the length L2 of the second bar pattern 2b is shortened (the second bar pattern 2b has a depth The pie is in the form), since the laser beam is relatively weak when the common laser head 130 passes through the first light guide plate 1a, the length L1 of the first bar pattern 2a is relatively long (at this time). The first bar pattern 2a is relatively less deep in shape).

When the processing is performed in this manner, the depths L1 and L2 of the first and second bar patterns 2a and 2b formed on the first and second light guide plates 1a and 1b may be different in depth. Therefore, it is possible to manufacture a good product to satisfy the required luminance conditions.

As a result, the lengths, pitches and spacings of the bar patterns 2a and 2b in the first and second light guide plates 1a and 1b manufactured together may be different as long as they satisfy the required luminance conditions. For reference, the minimum length of the bar patterns 2a and 2b may be designed to be 200 μm or more, and the pitch between the bar patterns 2a and 2b may be 2000 μm, but the present invention is not limited thereto.

On the other hand, in addition to the above, the laser output from the common laser head 130 is output characteristics (Pout 1) having a certain deviation (deviation) to shake according to the time (t1, t2, t3), as shown in FIG. , Pout 2, Pout 3). Due to the output characteristics of the laser, a non-uniform bar pattern 2 (see FIG. 1) may be formed on the light guide plate 1 (see FIG. 1). In this embodiment, in order to average the output characteristics of the laser, a plurality of times The bar pattern 2 is divided and formed. That is, the common laser head 130 reciprocatingly driven in the X-axis direction with respect to the movement stage 120 moved in the Y-axis direction forms a pattern 2 while skipping each line of the light guide plate 1.

For example, when the number of reciprocating movements of the movement stage 120 moved in the Y-axis direction is one time, the common laser head 130 may use 2N + 1 of the pattern 2 when the movement stage 120 moves in the + Y-axis direction. For the (N = 0,1,2,3, ...) line, 2N + 2 of the pattern (2) when the moving stage 120 moves in the -Y axis direction (N = 0,1,2,3) A pattern (2) is formed for the lines. As such, when the common laser head 130 forms a pattern 2 on the light guide plate 1 while skipping the line based on the reciprocating motion of the moving stage 120, the light guide plate is generally used even if the laser shows output characteristics as shown in FIG. 7. It becomes possible to form the uniform pattern 2 in (1).

As another example, if the number of reciprocating movements of the movement stage 120 moved in the Y-axis direction is 1.5 times, the common laser head 130 may determine the pattern 2 when the movement stage 120 moves in the + Y-axis direction. For the 3N + 1 (N = 0,1,2,3, ...) line, 3N + 2 (N = 0,1,3) of the pattern (2) when the moving stage 120 moves in the -Y axis direction. 3N + 3 (N = 0,1,2,3, ...) of the pattern (2) for the 2,3, ...) line and when the moving stage 120 moves back in the + Y axis direction. A pattern 2 is formed for the line. In the present embodiment, this method is applied, but the scope of the present invention does not need to be limited thereto.

If the number of reciprocating motions of the movement stage 120 moved in the Y-axis direction is twice, the common laser head 130 may use 4N + of the pattern 2 when the movement stage 120 moves in the + Y-axis direction. For line 1 (N = 0,1,2,3, ...), 4N + 2 (N = 0,1,2, of the pattern 2) when the movement stage 120 moves in the -Y axis direction. For the 3, ...) line, for the 4N + 3 (N = 0,1,2,3, ...) line of the pattern 2 when the moving stage 120 moves again in the + Y-axis direction Then, when the moving stage 120 moves in the -Y axis direction, the pattern 2 may be formed with respect to the 4N + 4 (N = 0,1,2,3, ...) line of the pattern 2. .

Referring to the operation of the light guide plate manufacturing apparatus having such a configuration is as follows.

First, as shown in FIG. 8, the first and second light guide plates 1a and 1b are loaded on the moving stage 120. At this time, the first and second light guide plates 1a and 1b are brought into close contact with the reference alignment rib 124a and the left and right side walls are in close contact with the side alignment alignment rib 124b, and then the movable pressure pad ( 124c is used to press the rear side walls of the first and second light guide plates 1a and 1b toward the reference alignment rib 124a. Then, the loading positions for the first and second light guide plates 1a and 1b are aligned.

As such, when the loading of the first and second LGPs 1a and 1b is completed and the operation is started, the common laser head 130 passes through several paths of the laser beam from the laser source L / S (see FIG. 6). Is passed to.

Subsequently, the moving stage 120 is moved stepwise and sequentially in the + Y axis or -Y axis direction by the stage moving unit 150, and at the same time, the common laser head 130 is moved by the head driving unit 160 by the head driving unit 160. As the reciprocating driving direction is performed, the bar patterns 2a and 2b are formed on the first and second light guide plates 1a and 1b, respectively.

Referring back to the above description, the common laser head 130, which is reciprocally driven, has a 3N + 1 (N = 0, 3, 0) pattern of the patterns 2a and 2b when the moving stage 120 moves in the + Y axis direction. Patterns 2a and 2b are formed primarily on the lines 1,2,3, ...). Subsequently, when the movement stage 120 is moved in the -Y-axis direction, the common laser head 130 reciprocally driven is 3N + 2 (N = 0,1,2,3, ..) of the patterns 2a and 2b. .) Secondly, the patterns 2a and 2b are formed with respect to the line. When the moving stage 120 is moved again in the + Y axis direction, the common laser head 130 reciprocally driven is 3N + 3 (N = 0,1,2,3, ..) of the patterns 2a and 2b. The pattern (2a, 2b) is formed in three orders for the line to complete.

In other words, the movement stage 120 is moved three times in the + Y, -Y, and + Y axis directions, and the first and second light guide plates 1a are moved while the common laser head 130 skips the line. The patterns 2a and 2b are formed on the first and second light guide plates 1a and 1b, and thus the uniform patterns 2a and 2b may be formed on the first and second light guide plates 1a and 1b. In particular, in the present embodiment, since two light guide plates 1a and 1b can be processed at a time, productivity per unit time can also be improved.

As described above, according to the present embodiment, it is possible to form uniform patterns 2a and 2b on the first and second light guide plates 1a and 1b while improving productivity per unit time.

10 is a plan view of principal parts of a light guide plate manufacturing apparatus according to a second embodiment of the present invention.

In the above-described embodiment, one side aligning rib 124b is provided in the center area of the moving stage 120, but as shown in FIG. 10, two side aligning ribs 224a are positioned on the moving stage 120. , 224b may be provided, and the first and second light guide plates 1a and 1b may be aligned while being in contact with the side alignment alignment ribs 224a and 224b, respectively.

As described above, the present invention is not limited to the described embodiments, and various modifications and changes can be made without departing from the spirit and scope of the present invention, which will be apparent to those skilled in the art. Therefore, such modifications or variations will have to be belong to the claims of the present invention.

1 is a schematic plan view of a light guide plate manufactured by a light guide plate manufacturing apparatus according to a first embodiment of the present invention.

2 is a perspective view of a light guide plate manufacturing apparatus according to a first embodiment of the present invention.

3 is a partial cutaway perspective view of FIG. 2.

4 is a front view of FIG. 2.

5 is an enlarged perspective view of the main portion of the belt.

FIG. 6 is a partial plan view of FIG. 2 illustrating a layout relationship of a common laser head, a moving stage, and a light guide plate.

7 is a graph schematically illustrating output characteristics of a carbon dioxide laser.

8 and 9 are perspective views illustrating a process of manufacturing a light guide plate by the light guide plate manufacturing apparatus of FIG. 2, respectively.

10 is a plan view of principal parts of a light guide plate manufacturing apparatus according to a second embodiment of the present invention.

* Explanation of symbols for the main parts of the drawings

1,1a, 1b: Light guide plate 2,2a, 2b: Bar pattern

110: device body 112: dust inhaler

120: moving stage 121a, 121b: light guide plate loading unit

122: vacuum suction hole 123: weight reducing groove

124: alignment portion 124a: reference alignment rib

124b: Alignment rib for side alignment 124c: Removable pressure pad

125: sober bracket 130: common laser head

140: base plate 143: shock absorber

150: stage moving unit 151: moving unit

152: detector 154: guide

160: head drive unit 161: motor

162: driving pulley 163: driven pulley

164 belt 170 belt support roller

Claims (18)

A plurality of light guide plates loaded on an upper surface thereof and movable in a long side or a short side direction of the light guide plate; And Receiving a laser provided from a laser source to form a predetermined pattern on a surface of the plurality of light guide plates loaded on the moving stage, and including a common laser head commonly applied to the plurality of light guide plates Light guide plate manufacturing apparatus. The method of claim 1, The moving stage is a light guide plate manufacturing apparatus, characterized in that the upper (dual) moving stage is provided with a first and second light guide plate loading section is loaded with two light guide plates. The method of claim 2, The common laser head is reciprocally driven in a direction intersecting with a direction in which the moving stage moves, so that a bar pattern having different first and second lengths is formed on the first and second light guide plates, respectively. Light guide plate manufacturing apparatus further comprises a control unit for controlling the head. The method of claim 3, The control unit controls the common laser head such that the first and second lengths are set based on an average output of laser beams irradiated from the common laser head to the first and second light guide plates. Device. The method of claim 4, wherein When the common laser head reaches a shorter distance from the laser source to the common laser head when positioned in the second light guide plate than when the common laser head is located in the first light guide plate, the controller is further configured to provide the And controlling the common laser head so that the bar pattern of the second length is shorter. The method of claim 1, The light guide plate manufacturing apparatus further comprises an alignment unit provided on the upper surface of the moving stage to align the loading position of the plurality of light guide plates. The method of claim 6, The alignment part may include at least one light guide plate provided on an upper surface of the moving stage and at least one reference alignment rib forming a reference of a loading position for the plurality of light guide plates while one side walls of the plurality of light guide plates are in close contact with each other. Manufacturing equipment. The method of claim 7, wherein The alignment portion is disposed in a direction crossing with respect to the reference alignment rib between the plurality of light guide plates loaded on the moving stage, and the other side walls of the plurality of light guide plates are closely contacted with the reference alignment ribs. Light guide plate manufacturing apparatus further comprises a side alignment aligning rib for aligning the light guide plate. The method of claim 8, The moving stage is a dual moving stage provided with first and second light guide plate loading parts on which two light guide plates are loaded. The side alignment align rib is a common side alignment align rib disposed between the first and second light guide plates to align the first and second light guide plates. The alignment part further comprises a movable pressure pad for pressing the plurality of light guide plates from the opposite side of the reference alignment rib toward the reference alignment rib to prevent the plurality of light guide plates from being randomly moved. Device. The method of claim 3, A base plate provided in a lower region of the movement stage to support the movement stage in a Y-axis direction, which is a short side direction of the light guide plate; And And a stage moving part provided on the moving stage and the base plate to move the moving stage in the Y-axis direction with respect to the base plate. The method of claim 10, The stage moving unit, A moving unit coupled to the moving stage and the base plate to move the moving stage in the Y-axis direction; And Light guide plate manufacturing apparatus characterized in that it comprises a detection unit for transmitting the detection signal to the control unit by detecting the moving distance of the mobile unit in stages. The method of claim 11, The mobile unit is a linear motor, The light guide plate manufacturing apparatus, characterized in that the lower portion of the moving stage is detected by the sensing unit, the display unit for displaying the moving distance of the mobile unit is further formed. The method of claim 11, The stage moving part further comprises a pair of guides provided on both sides of the moving unit to be symmetrical to guide the movement of the moving stage. The method of claim 13, Each of the pair of guides, A rail block coupled to any one of the moving stage and the base plate; And And a rail coupled to the other one of the movable stage and the base plate and slidably engaged with the rail block in a dove tail shape. The method of claim 10, At least one shock absorber provided on the base plate to prevent excessive forward or backward movement of the moving stage; And The light guide plate manufacturing apparatus further comprises a sober bracket provided in said moving stage and selectively contacting with said shock absorber. The method of claim 1, The moving stage, A plurality of vacuum adsorption holes for adsorbing the plurality of light guide plates in a vacuum; And And a plurality of weight reducing grooves formed to be recessed between the plurality of vacuum suction holes to reduce the weight of the moving stage. Forming a bar pattern having a first length on a first light guide plate seated on one side of the moving stage by using a common laser head; And And forming a bar pattern having a second length different from the first length by using the common laser head on a second light guide plate disposed side by side with the first light guide plate on the other side of the moving stage. Light guide plate manufacturing method. The method of claim 17, The first length and the second length are set based on an average output of a laser beam radiated from the common laser head to the first light guide plate and an average output of a laser beam radiated from the common laser head to the second light guide plate. Light guide plate manufacturing method characterized in that the.

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