CN111316033A - System for manufacturing surface light source device and method for manufacturing surface light source device - Google Patents

Abstract

The invention provides a manufacturing system of a surface light source device and a manufacturing method of the surface light source device, which can restrain light leakage of the surface light source device. A manufacturing system of a surface light source device comprises: a first bonding section that bonds the prism sheet to the light-shielding tape; a first imaging unit that images the light-shielding tape to which the prism sheet is attached from a thickness direction of the light-shielding tape, and images a frame that surrounds a side surface of the light guide plate and accommodates the light guide plate from the thickness direction of the frame; a calculating unit that calculates coordinates of a contour point and coordinates of a center point of the light-shielding tape from the image data of the light-shielding tape to which the prism sheet is attached, and calculates coordinates of a contour point and coordinates of a center point of the frame from the image data of the frame; and a second bonding section that bonds the light-shielding tape to which the prism sheet is bonded to the frame by adjusting at least one of a position of the light-shielding tape to which the prism sheet is bonded and a position of the frame based on coordinates of the contour point and coordinates of the center point of the light-shielding tape and coordinates of the contour point and coordinates of the center point of the frame.

Description

System for manufacturing surface light source device and method for manufacturing surface light source device

Technical Field

The present invention relates to a system for manufacturing a surface light source device and a method for manufacturing a surface light source device.

Background

In recent years, electronic devices have been reduced in size and thickness. In the liquid crystal display device mounted on the electronic apparatus, there is a demand for a narrower frame and a thinner display region to obtain a larger display region with the same area. As a backlight of a display device, for example, a surface Light source device of a side Light type (also referred to as an edge Light type) using a Light Guide plate (also referred to as a Light Guide) using an LED (Light Emitting Diode) Emitting white Light as a Light source is used. Fig. 12 is a diagram illustrating an example of a method for manufacturing the surface light source device 110. First, the light guide plate 102 and the light source 103 are disposed inside the frame 101, and the diffusion sheet 104 is placed on the light exit surface (upper surface) of the light guide plate 102. After the prism sheet 105 is placed on the diffusion sheet 104, the light-shielding double-sided tape 106 is attached to the frame 101 and the prism sheet 105, thereby manufacturing the surface light source device 110. In the manufacture of a liquid crystal display element, it has been proposed to perform position bonding of two substrates by image processing (see patent document 1). An alignment camera has been proposed to align the liquid crystal panel and the bonding sheet (see patent document 2).

Documents of the prior art

Patent document

Patent document 1: japanese unexamined patent publication No. 9-127546

Patent document 2: international publication No. 2013/129256

Disclosure of Invention

Technical problem to be solved by the invention

Fig. 13 is a sectional view of the surface light source device 110. A reflective sheet 107 is disposed on the lower surface of the light guide plate 102. In fig. 13, two prism sheets 105 are attached to the diffusion sheet 104. As shown in fig. 13, when the width W1 of the frame 101 and the width W2 of the light-shielding double-sided tape 106 are large, the surface light source device 110 does not leak light even if the position where the prism sheet 105 is placed is slightly deviated or the position where the light-shielding double-sided tape 106 is attached is slightly deviated. Fig. 14 is a sectional view of the surface light source device 110. In fig. 14, one prism sheet 105 is attached to the diffusion sheet 104. As shown in fig. 14, in response to the recent demand for a narrower bezel, the width W1 of the frame 101 and the width W2 of the light-shielding double-sided tape 106 are reduced. Therefore, in the case where the position where the prism sheet 105 is placed is deviated and the position where the light shielding double-sided tape 106 is pasted is deviated, the light leakage from the surface light source device 110 may occur.

In view of the above problems, an object of the present invention is to suppress light leakage from a surface light source device.

Technical solution for solving technical problem

In the present invention, the following means is adopted to solve the above problems. That is, the present invention is a system for manufacturing a surface light source device, including: a first bonding section that bonds the prism sheet to the light-shielding tape; a first imaging unit that images the light-shielding tape to which the prism sheet is attached from a thickness direction of the light-shielding tape, and images a frame that surrounds a side surface of the light guide plate and accommodates the light guide plate from the thickness direction of the frame; a calculating unit that calculates coordinates of a contour point and coordinates of a center point of the light-shielding tape from the image data of the light-shielding tape to which the prism sheet is attached, and calculates coordinates of a contour point and coordinates of a center point of the frame from the image data of the frame; and a second bonding section that bonds the light-shielding tape to which the prism sheet is bonded to the frame by adjusting at least one of a position of the light-shielding tape to which the prism sheet is bonded and a position of the frame based on coordinates of the contour point and coordinates of the center point of the light-shielding tape and coordinates of the contour point and coordinates of the center point of the frame.

In the system for manufacturing a surface light source device of the present invention, after the prism sheet is bonded to the light-shielding double-sided tape, the light-shielding double-sided tape to which the prism sheet is bonded to the frame. In the manufacturing system of the surface light source device of the present invention, at least one of the position of the light-shielding tape to which the prism sheet is attached and the position of the frame is adjusted based on the coordinates of the contour point and the coordinates of the center point of the light-shielding tape and the coordinates of the contour point and the coordinates of the center point of the frame, and the light-shielding tape to which the prism sheet is attached and the frame are attached. Therefore, the bonding precision of the frame and the light-shielding double-sided tape is improved. Even when the width of the frame is small or the width of the light-shielding double-sided tape is small, the light-shielding double-sided tape and the frame can be bonded with high accuracy. Since the positional deviation between the double-sided light-shielding tape and the frame can be suppressed, the occurrence of light leakage in the surface light source device 1 can be suppressed.

The manufacturing system of the surface light source device of the present invention may further include a second imaging unit that images the prism sheet from the thickness direction of the prism sheet and images the light shielding tape from the thickness direction of the light shielding tape, wherein the calculation unit calculates coordinates of a contour point and coordinates of a center point of the prism sheet from imaging data of the prism sheet and calculates coordinates of a contour point and coordinates of a center point of the light shielding tape from imaging data of the light shielding tape, and the first bonding unit adjusts at least one of positions of the prism sheet and the light shielding tape based on the coordinates of the contour point and the coordinates of the center point of the prism sheet and the coordinates of the center point and the coordinates of the contour point of the light shielding tape and bonds the prism sheet to the light shielding tape.

In the system for manufacturing a surface light source device of the present invention, the second imaging unit may image the prism sheet and then image the light-shielding tape in a state where the light-shielding tape is disposed so as to overlap the prism sheet with the light-shielding tape. In the system for manufacturing a surface light source device of the present invention, the second imaging unit may image the prism sheet in a state where the prism sheet is arranged by overlapping the light-shielding tape and the prism sheet after imaging the light-shielding tape.

In the system for manufacturing a surface light source device of the present invention, the first imaging unit may image the frame and then image the light-shielding tape to which the prism sheet is attached in a state where the light-shielding tape to which the prism sheet is attached is arranged so as to overlap the frame. In the system for manufacturing a surface light source device of the present invention, the first imaging unit may image the light-shielding tape to which the prism sheet is attached, and then image the frame in a state where the light-shielding tape to which the prism sheet is attached is placed on the frame.

Further, the present invention is a method for manufacturing a surface light source device, including: a first bonding step of bonding the prism sheet to the light-shielding tape; an imaging step of imaging the light-shielding tape to which the prism sheet is attached from the thickness direction of the light-shielding tape, and imaging a frame that surrounds the side surface of the light guide plate and accommodates the light guide plate from the thickness direction of the frame; a calculating step of calculating coordinates of a contour point and coordinates of a center point of the light-shielding tape from the image data of the light-shielding tape to which the prism sheet is attached, and calculating coordinates of a contour point and coordinates of a center point of the frame from the image data of the frame; and a second bonding step of adjusting at least one of a position of the light-shielding tape to which the prism sheet is bonded and a position of the frame based on the coordinates of the contour point and the coordinates of the center point of the light-shielding tape and the coordinates of the contour point and the coordinates of the center point of the frame, and bonding the light-shielding tape to which the prism sheet is bonded and the frame.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, light leakage from the surface light source device can be suppressed.

Drawings

Fig. 1 is a diagram showing an example of a manufacturing system according to an embodiment.

Fig. 2 is a perspective view illustrating the structure of the liquid crystal display device of the embodiment.

Fig. 3 is a perspective view illustrating a structure of a surface light source device of an embodiment.

Fig. 4 is a block diagram showing an example of the manufacturing system according to the embodiment.

Fig. 5 is an explanatory view of a process of attaching a prism sheet to a light-shielding double-sided tape.

Fig. 6 is a top view of a prism sheet.

Fig. 7 is a top view of a prism sheet.

Fig. 8 is an explanatory view of a process of attaching a prism sheet to a light-shielding double-sided tape.

Fig. 9 is an explanatory view of a process of attaching the light-shielding double-sided tape to which the prism sheet is attached to the frame.

Fig. 10 is an explanatory view of a process of attaching the light-shielding double-sided tape to which the prism sheet is attached to the frame.

Fig. 11 is a plan view of a surface light source device of an exemplary embodiment.

Fig. 12 is a view showing an example of a method for manufacturing the surface light source device.

Fig. 13 is a sectional view of the surface light source device.

Fig. 14 is a sectional view of the surface light source device.

Detailed Description

Embodiments of the present invention will be described below with reference to the drawings. The embodiments described below are merely examples for carrying out the present invention, and the present invention is not limited to the specific configurations described below.

In the following embodiments, a liquid crystal display device will be described as a "display device", and a backlight unit of the liquid crystal display device will be described as a "surface light source device". The "surface light source device" may be used for applications other than a backlight unit, such as a front surface light source disposed on the front surface of a display device including a display panel and an electronic paper.

Application example

Fig. 1 is a diagram showing an example of a manufacturing system according to an embodiment. The process indicated by the broken line a in fig. 1 will be described. In the step indicated by the broken line a in fig. 1, the prism sheet 15 and the light-shielding double-sided tape 16 are arranged, and the prism sheet 15 and the light-shielding double-sided tape 16 are imaged. After the prism sheet 15 is arranged and the prism sheet 15 is photographed, the light-shielding double-sided tape 16 may be arranged and the light-shielding double-sided tape 16 may be photographed. After the light-shielding double-sided tape 16 is disposed and the light-shielding double-sided tape 16 is imaged, the prism sheet 15 may be disposed and the prism sheet 15 may be imaged. Next, based on the image data of the prism sheet 15 and the image data of the light-shielding double-sided tape 16, at least one of the position of the prism sheet 15 and the position of the light-shielding double-sided tape 16 is adjusted, and the prism sheet 15 and the light-shielding double-sided tape 16 are bonded. The light-shielding double-sided tape 16 is an example of a light-shielding tape.

The process indicated by the broken line B in fig. 1 will be described. Prior to the step indicated by the broken line B in fig. 1, the light guide plate 11, the light source 12, and the frame 13 surrounding the side surface of the light guide plate 11 are arranged, and the diffusion sheet 14 is placed on the light exit surface of the light guide plate 11. In the step indicated by the broken line B in fig. 1, the frame 13 and the light-shielding double-sided tape 16 to which the prism sheet 15 is attached are disposed, and the frame 13 and the light-shielding double-sided tape 16 to which the prism sheet 15 is attached are imaged. After the frame 13 is disposed and the frame 13 is photographed, the light-shielding double-sided tape 16 to which the prism sheet 15 is attached is disposed and the light-shielding double-sided tape 16 to which the prism sheet 15 is attached can be photographed. After the light-shielding double-sided tape 16 to which the prism sheet 15 is attached is disposed and the light-shielding double-sided tape 16 to which the prism sheet 15 is attached is imaged, the frame 13 may be disposed and the frame 13 may be imaged. Next, based on the image data of the frame 13 and the image data of the light-shielding double-sided tape 16 to which the prism sheet 15 is attached, at least one of the position of the frame 13 and the position of the light-shielding double-sided tape 16 is adjusted, and the frame 13 and the light-shielding double-sided tape 16 are attached. The frame 13 and the light-shielding double-sided tape 16 are bonded to each other, thereby manufacturing the surface light source device 1.

As shown in fig. 1, after the step of bonding the prism sheet 15 and the light-shielding double-sided tape 16, the step of bonding the frame 13 and the light-shielding double-sided tape 16 is performed. That is, the step of attaching the prism sheet 15 and the light-shielding double-sided tape 16 and the step of attaching the frame 13 and the light-shielding double-sided tape 16 are different steps. Since the prism sheet 15 and the light-shielding double-sided tape 16 are bonded by adjusting at least one of the position of the prism sheet 15 and the position of the light-shielding double-sided tape 16, the accuracy of bonding the prism sheet 15 and the light-shielding double-sided tape 16 is improved. Since the frame 13 and the light-shielding double-sided tape 16 are bonded by adjusting at least one of the position of the frame 13 and the position of the light-shielding double-sided tape 16, the bonding accuracy between the frame 13 and the light-shielding double-sided tape 16 is improved. After the step of bonding the prism sheet 15 and the light-shielding double-sided tape 16, the step of bonding the frame 13 and the light-shielding double-sided tape 16 is performed. Therefore, the prism sheet 15 is placed on the diffusion sheet 14 by attaching the frame 13 to the light-shielding double-sided tape 16. Therefore, the accuracy of the position where the prism sheet 15 is placed on the diffusion sheet 14 is improved.

According to the embodiment, the position of the diffusion sheet 14 on which the prism sheet 15 is placed can be prevented from being shifted, and the position of the light-shielding double-sided tape 16 to be stuck can be prevented from being shifted, so that the light leakage from the surface light source device 1 can be prevented.

(Structure of liquid Crystal display device)

Fig. 2 is a perspective view illustrating the structure of the liquid crystal display device of the embodiment. As shown in fig. 2, the liquid crystal display device includes: a surface light source device 1 disposed as a backlight unit, and a display panel 2 receiving light emitted from the surface light source device 1. The display panel 2 displays an image by applying a voltage to the liquid crystal sealed with the glass plate interposed therebetween, increasing or decreasing light transmittance, or the like. Hereinafter, the surface light source device 1 will be described with the display panel 2 side as the upper surface side and the opposite surface side as the lower surface side. The liquid crystal display device can be mounted on various electronic apparatuses. Examples of the electronic device having the liquid crystal display device include a smartphone, a digital camera, a tablet terminal, an electronic book, a wearable device, a navigation device, an electronic dictionary, and an electronic billboard.

(Structure of surface light source device 1)

Fig. 3 is a perspective view illustrating the structure of the surface light source device 1 of the embodiment. The surface light source device 1 of the embodiment includes: a light guide plate 11, a light source 12, a frame 13, a flexible printed circuit board (hereinafter also referred to as "FPC") 17, and a fixing member 18. Further, the surface light source device 1 includes: a diffusion sheet 14, a prism sheet 15, and a light-shielding double-sided tape 16 laminated in this order on the light exit surface side (upper surface side) of the light guide plate 11, and a reflective sheet 19 disposed on the lower surface side of the light guide plate 11.

The light guide plate 11 is roughly in the shape of a flat plate and is formed of a light-transmitting material such as a polycarbonate resin or a polymethyl methacrylate resin. The upper surface of the light guide plate 11 is a light exit surface from which light exits, and is a surface facing the display panel 2. The light guide plate 11 guides light entering the light guide plate 11 from the light source 12 to the light exit surface, and the entire or a part of the light exit surface emits light. The light guide plate 11 may include a light guide plate body and a light introduction portion having a height higher than that of the light guide plate body. The light emitted from the light source 12 is efficiently incident into the light guide plate main body from the light introduction part, and the light utilization efficiency of the light guide plate 11 is improved. By making the light guide plate main body thinner than the light introducing portion, the surface light source device 1 can be made thinner, and the liquid crystal display device having the surface light source device 1 can be made thinner. However, the light guide plate 11 according to the embodiment may have a flat plate shape without a light introduction portion.

The light source 12 emits white light from the fluorescent portion. The light source 12 is, for example, an LED package, but a light source other than an LED package may be used. The light source 12 is formed by sealing a light-transmitting resin (resin layer) containing a phosphor in an LED chip which is a light-emitting element. Alternatively, the LED chip may be provided with a phosphor layer on the light exit surface of the light guide plate 11, instead of the phosphor, or the reflective sheet 19 may be provided with a phosphor layer. The light source 12 is driven by power supplied from the FPC17 and turns on. As the light source 12, an LED light source other than white may be used. The light source 12 is disposed at a position facing the light incident surface of the light guide plate 11. For example, the light source 12 is attached to the FPC17 with the light emitting surface of the light source 12 facing the light incident surface of the light guide plate 11. A plurality of light sources 12 may be mounted in a row at a constant interval on the FPC 17.

The frame 13 houses the light guide plate 11, the light source 12, the diffusion sheet 14, the prism sheet 15, the FPC17, the fixing member 18, and the reflective sheet 19. The frame 13 may be a frame (frame-shaped member) surrounding the side surface of the light guide plate 11, or may be a case (box-shaped member) having a frame surrounding the side surface of the light guide plate 11 and a bottom plate on which the frame is erected. The frame body may be formed of a four-sided side wall member, a circular side wall member having an opening, or an oval side wall member having an opening. The corner portions of the side wall members on the four sides of the frame may be formed in a right-angled shape, or the corner portions of the side wall members on the four sides of the frame may be formed in an R-shape. The frame 13 is not limited to the above example, and may have another shape.

A diffusion sheet 14 is disposed on the light exit surface of the light guide plate 11, and one or two prism sheets 15 are disposed on the diffusion sheet 14. The diffusion sheet 14 is a translucent resin film, and diffuses light emitted from the light exit surface of the light guide plate 11 to widen the directional characteristic of the light. The prism sheet 15 is a transparent resin film having a triangular prism-shaped fine pattern formed on the upper surface thereof, and collects light diffused by the diffusion sheet 14, thereby increasing luminance when the surface light source device 1 is viewed from the upper surface side. The prism sheet 15 may have a quadrangular shape or a quadrangular shape having R-shaped corners when viewed from the normal direction of the upper surface of the prism sheet 15. The prism sheet 15 is not limited to the above example, and may have another shape. The light-shielding double-sided tape 16 is a black adhesive tape having adhesive surfaces on both upper and lower surfaces. The light-shielding double-sided adhesive tape 16 may also have a frame shape (ring shape) having an opening. The light-shielding double-sided tape 16 is disposed along the outer peripheral portion of the frame 13, and suppresses light leakage to the outside of the surface light source device 1. The light-shielding double-sided tape 16 may be formed of a plurality of members. For example, the light-shielding double-sided tape 16 may have two members, and be disposed along the outer peripheral portion of the frame 13 with the two members facing each other. The light-shielding double-sided tape 16 is not limited to the above example, and the light-shielding double-sided tape 16 may have another shape.

FPC17 is a wiring board in which wiring is provided on a flexible insulating film or base material by a conductive foil, and a protective insulating film or a coverlay or a resin (photosensitive resin) is bonded to the surface. The FPC17 is provided with wiring. The wiring of the FPC17 is used to supply power to the light source 12. The fixing member 18 is disposed on the lower surface of the FPC17, for example, and fixes the FPC17 to the light guide plate 11. The fixing member 18 is, for example, a double-sided adhesive tape having an upper surface and a lower surface as adhesive surfaces.

The reflective sheet 19 is disposed in contact with the lower surface of the light guide plate 11, and is bonded to the frame 13 via an adhesive layer. The lower surface of the light guide plate 11 is the surface opposite to the upper surface of the light guide plate 11. The reflective sheet 19 is a smooth sheet formed of a highly reflective film having a multilayer film structure, a white resin sheet having a high reflectance, a metal foil, or the like, and reflects light so that the light in the light guide plate 11 does not leak from the lower surface of the surface light source device 1. When the frame 13 is a case having a housing and a bottom plate, the reflective sheet 19 is disposed between the light guide plate 11 and the bottom plate of the frame 13.

Fig. 4 is a block diagram showing an example of the manufacturing system 20 according to the embodiment. The manufacturing system 20 includes: a pasting unit 21, an imaging unit 22, a pasting unit 23, an imaging unit 24, a control unit 25, and a storage unit 26. The joining section 21 has a mechanism for gripping the prism sheet 15 and a mechanism for gripping the light-shielding double-sided tape 16, and joins the prism sheet 15 and the light-shielding double-sided tape 16. The attachment portion 21 is an example of a first attachment portion. The imaging unit 22 includes one or more cameras. The imaging section 22 images the prism sheet 15 and images the light-shielding double-sided tape 16. The imaging unit 22 is an example of a second imaging unit. The joining section 23 has a mechanism for gripping the frame 13 and a mechanism for gripping the light-shielding double-sided tape 16 to which the prism sheet 15 is joined, and joins the light-shielding double-sided tape 16 to which the prism sheet 15 is joined to the frame 13. The attachment portion 23 is an example of a second attachment portion. The imaging section 24 has one or more cameras. The imaging unit 24 images the frame 13 and images the light-shielding double-sided tape 16 to which the prism sheet 15 is attached. The imaging unit 24 is an example of a first imaging unit.

The control Unit 25 includes processors such as a CPU (Central Processing Unit) and an MPU (micro Processing Unit). The control unit 25 may be constituted by one CPU or MPU, or may be constituted by a combination of a plurality of CPUs and a plurality of MPUs. The CPU and MPU are not limited to a single processor, and may have a multiprocessor configuration. The control unit 25 executes various processes in accordance with a computer program that is executable and developed in the storage unit 26. The storage unit 26 includes memories such as a RAM (Random Access Memory) and a ROM (Read Only Memory). The storage unit 26 stores or temporarily stores imaging data imaged by the imaging units 22 and 24, data obtained by processing executed by the control unit 25, and the like. The control unit 25 and the storage unit 26 may be integrated. The plurality of control units 25 may be connected to the attaching unit 21 and the attaching unit 23, respectively, and the attaching unit 21 and the attaching unit 23 may have the control units 25, respectively. The control unit 25 is an example of the calculation unit.

Fig. 5 is an explanatory diagram of a process of bonding the prism sheet 15 and the light-shielding double-sided tape 16. In the steps (a1) to (A3) of fig. 5, after the position of the prism sheet 15 is adjusted, the position of the light-shielding double-sided tape 16 is adjusted, and the prism sheet 15 and the light-shielding double-sided tape 16 are bonded. In the example shown in fig. 5, the imaging unit 22 includes a plurality of cameras 31. In the step (a1) of fig. 5, the joining section 21 positions the prism sheet 15 at a predetermined position with the prism sheet 15 gripped, and the camera 31 photographs the prism sheet 15 from the thickness direction of the prism sheet 15. In the example shown in fig. 5, the camera 31 photographs the prism sheet 15 from the upper surface side of the prism sheet 15. The upper surface of the prism sheet 15 is a contact surface of the prism sheet 15 with the light-shielding double-sided tape 16. The shot data of the prism sheet 15 shot by the camera 31 is stored in the storage section 26. For example, when the prism sheet 15 is a square in a plan view (viewed from the normal direction of the upper surface of the prism sheet 15), the four cameras 31 may capture images of regions including the four corners of the prism sheet 15. Not limited to the example shown in fig. 5, one camera 31 may photograph the prism sheet 15.

The control unit 25 acquires the image data of the prism sheet 15 from the storage unit 26, and calculates the coordinates of the contour points of the prism sheet 15 according to the shape of the prism sheet 15. For example, when the prism sheet 15 is a quadrangle in a plan view, the coordinates of the contour points of the prism sheet 15 may be the coordinates of the vertices of the quadrangle. The control unit 25 calculates the coordinates of the center point of the prism sheet 15 from the coordinates of the contour points of the prism sheet 15. The control unit 25 calculates an average value of the coordinates of the plurality of contour points of the prism sheet 15 as the coordinates of the center point of the prism sheet 15. For example, when the prism sheet 15 is a quadrangle in a plan view, the coordinates of the center point of the prism sheet 15 may be an average value of the coordinates of the vertices of the quadrangle. The storage unit 26 stores coordinates of the reference contour point of the prism sheet 15 and coordinates of the reference center point of the prism sheet 15 in advance. The coordinates of the reference contour point and the coordinates of the reference center point of the prism sheet 15 are coordinates for accurately arranging the prism sheet 15 at a predetermined position. The pasting section 21 adjusts the position of the center point of the prism sheet 15 so that the coordinates of the center point of the prism sheet 15 match the coordinates of the reference center point of the prism sheet 15. The attaching portion 21 adjusts the position of the center point of the prism sheet 15 by moving the prism sheet 15 in the plane direction of the prism sheet 15. The pasting section 21 adjusts the position of the contour point of the prism sheet 15 so that the coordinates of the contour point of the prism sheet 15 match the coordinates of the reference contour point of the prism sheet 15. The pasting section 21 adjusts the position of the contour point of the prism sheet 15 by moving the prism sheet 15 in the planar direction of the prism sheet 15. The plane direction of the prism sheet 15 is orthogonal to the thickness direction of the prism sheet 15.

An example of the position adjustment of the contour points of the prism sheet 15 will be described with reference to fig. 6 and 7. Fig. 6 and 7 are plan views of the prism sheet 15. Fig. 6 shows coordinates (X1, Y1) of the center point of the prism sheet 15 and coordinates (X2, Y2) of the contour point of the prism sheet 15. The controller 25 calculates an angle (θ 1) formed by a line L1 connecting the coordinates (X1, Y1) of the center point of the prism sheet 15 and the coordinates (X2, Y2) of the contour point of the prism sheet 15 and the contour line L2 of the prism sheet 15. Fig. 7 shows the coordinates (X3, Y3) of the reference center point of the prism sheet 15 and the coordinates (X4, Y4) of the reference contour point of the prism sheet 15. The controller 25 calculates an angle (θ 2) formed by a line L3 connecting the coordinates (X3, Y3) of the reference center point of the prism sheet 15 and the coordinates (X4, Y4) of the reference contour point of the prism sheet 15 and the reference contour line L4 of the prism sheet 15. The pasting section 21 adjusts the position of the contour point of the prism sheet 15 so that the angle (θ 1) matches the angle (θ 2).

After the position of the center point and the position of the contour point of the prism sheet 15 are adjusted, the camera 31 images the prism sheet 15, and the control unit 25 calculates the coordinates of the contour point and the coordinates of the center point of the prism sheet 15. The control unit 25 determines whether or not the coordinates of the contour point of the prism sheet 15 match the coordinates of the reference contour point of the prism sheet 15. The control portion 25 determines whether or not the coordinates of the center point of the prism sheet 15 match the coordinates of the reference center point of the prism sheet 15. When the coordinates of the contour point of the prism sheet 15 match the coordinates of the reference contour point of the prism sheet 15 and the coordinates of the center point of the prism sheet 15 match the coordinates of the reference center point of the prism sheet 15, the process proceeds to step (a2) of fig. 5. On the other hand, when the coordinates of the contour points of the prism sheet 15 do not match the coordinates of the reference contour points of the prism sheet 15, or when the coordinates of the center point of the prism sheet 15 do not match the coordinates of the reference center point of the prism sheet 15, the pasting unit 21 adjusts the position of the center point and the position of the contour points of the prism sheet 15 again. In this way, the photographing and the position adjustment of the prism sheet 15 are repeated until the coordinates of the contour point of the prism sheet 15 coincide with the coordinates of the reference contour point of the prism sheet 15 and the coordinates of the center point of the prism sheet 15 coincide with the coordinates of the reference center point of the prism sheet 15.

The allowable range may be set with respect to the degree of coincidence between the coordinates of the contour point of the prism sheet 15 and the coordinates of the reference contour point of the prism sheet 15. For example, the control unit 25 may determine whether or not the coordinates of the center point of the prism sheet 15 match or are approximate to the coordinates of the reference center point of the prism sheet 15. The allowable range may be set with respect to the degree of coincidence between the coordinates of the center point of the prism sheet 15 and the coordinates of the reference center point of the prism sheet 15. For example, the control unit 25 may determine whether or not the coordinates of the center point of the prism sheet 15 match or are approximate to the coordinates of the reference center point of the prism sheet 15. In this case, the photographing of the prism sheet 15 and the adjustment of the position are repeated until the coordinates of the contour point of the prism sheet 15 coincide with or are approximate to the coordinates of the reference contour point of the prism sheet 15 and the coordinates of the center point of the prism sheet 15 coincide with or are approximate to the coordinates of the reference center point of the prism sheet 15.

In the step (a2) of fig. 5, the attaching unit 21 positions the light-shielding double-sided tape 16 at a predetermined position with the light-shielding double-sided tape 16 held, and the camera 31 photographs the light-shielding double-sided tape 16 from the thickness direction of the light-shielding double-sided tape 16. In the example shown in fig. 5, the light-shielding double-sided tape 16 is disposed so that the prism sheet 15 overlaps the light-shielding double-sided tape 16. In the example shown in fig. 5, the camera 31 photographs the light-shielding double-sided tape 16 from the upper surface side of the light-shielding double-sided tape 16. The upper surface of the light-shielding double-sided tape 16 is opposite to the surface of the light-shielding double-sided tape 16 in contact with the prism sheet 15. The shot data of the light-shielding double-sided tape 16 shot by the camera 31 is stored in the storage section 26.

The control unit 25 acquires the imaging data of the light-shielding double-sided tape 16 from the storage unit 26, and calculates the coordinates of the contour point of the light-shielding double-sided tape 16 according to the shape of the light-shielding double-sided tape 16. For example, when the light-shielding double-sided tape 16 has a frame shape having a quadrangular opening in a plan view (when viewed from a direction normal to the upper surface of the light-shielding double-sided tape 16), the coordinates of the contour points of the light-shielding double-sided tape 16 may be the coordinates of the vertices of the quadrangle of the opening of the light-shielding double-sided tape 16. The control unit 25 calculates coordinates of the center point of the light-shielding double-sided tape 16 from the coordinates of the contour point of the light-shielding double-sided tape 16. The control unit 25 may calculate an average value of coordinates of a plurality of contour points of the light-shielding double-sided tape 16 as coordinates of a center point of the light-shielding double-sided tape 16. For example, when the light-shielding double-sided tape 16 has a frame shape having a quadrangular opening in a plan view, the coordinates of the center point of the light-shielding double-sided tape 16 may be the average of the coordinates of the vertices of the quadrangle of the opening of the light-shielding double-sided tape 16.

The storage unit 26 stores coordinates of a reference contour point of the light-shielding double-sided tape 16 and coordinates of a reference center point of the light-shielding double-sided tape 16 in advance. The coordinates of the reference contour point and the coordinates of the reference center point of the light-shielding double-sided tape 16 are coordinates for accurately disposing the light-shielding double-sided tape 16 at a predetermined position. The attaching portion 21 adjusts the position of the center point of the light-shielding double-sided tape 16 so that the coordinates of the center point of the light-shielding double-sided tape 16 coincide with the coordinates of the reference center point of the light-shielding double-sided tape 16. The pasting section 21 adjusts the position of the center point of the light-shielding double-sided tape 16 by moving the light-shielding double-sided tape 16 in the planar direction of the light-shielding double-sided tape 16. The pasting section 21 adjusts the position of the outline point of the light-shielding double-sided tape 16 so that the coordinates of the outline point of the light-shielding double-sided tape 16 match the coordinates of the reference outline point of the light-shielding double-sided tape 16. The pasting section 21 adjusts the position of the outline point of the light-shielding double-sided tape 16 by moving the light-shielding double-sided tape 16 in the planar direction of the light-shielding double-sided tape 16. The plane direction of the light-shielding double-sided tape 16 is orthogonal to the thickness direction of the light-shielding double-sided tape 16. The position of the contour point of the light-shielding double-sided tape 16 may be adjusted by the same method as the position adjustment of the contour point of the prism sheet 15 shown in fig. 6 and 7.

After the position of the center point and the position of the contour point of the light-shielding double-sided tape 16 are adjusted, the camera 31 photographs the light-shielding double-sided tape 16, and the control unit 25 calculates the coordinates of the contour point and the coordinates of the center point of the light-shielding double-sided tape 16. The control unit 25 determines whether or not the coordinates of the contour point of the light-shielding double-sided tape 16 match the coordinates of the reference contour point of the light-shielding double-sided tape 16. The control unit 25 determines whether or not the coordinates of the center point of the light-shielding double-sided tape 16 match the coordinates of the reference center point of the light-shielding double-sided tape 16. When the coordinates of the outline point of the light-shielding double-sided tape 16 match the coordinates of the reference outline point of the light-shielding double-sided tape 16 and the coordinates of the center point of the light-shielding double-sided tape 16 match the coordinates of the reference center point of the light-shielding double-sided tape 16, the process proceeds to step (a3) of fig. 5. On the other hand, when the coordinates of the contour point of the light-shielding double-sided tape 16 do not match the coordinates of the reference contour point of the light-shielding double-sided tape 16, or when the coordinates of the center point of the light-shielding double-sided tape 16 do not match the coordinates of the reference center point of the light-shielding double-sided tape 16, the pasting section 21 adjusts the position of the center point and the position of the contour point of the light-shielding double-sided tape 16 again. In this way, the photographing and the position adjustment of the light-shielding double-sided tape 16 are repeated until the coordinates of the outline point of the light-shielding double-sided tape 16 coincide with the coordinates of the reference outline point of the light-shielding double-sided tape 16 and the coordinates of the center point of the light-shielding double-sided tape 16 coincide with the coordinates of the reference center point of the light-shielding double-sided tape 16.

The allowable range may be set with respect to the degree of coincidence between the coordinates of the contour point of the light-shielding double-sided tape 16 and the coordinates of the reference contour point of the light-shielding double-sided tape 16. For example, the control unit 25 may determine whether or not the coordinates of the center point of the light-shielding double-sided tape 16 match or are approximate to the coordinates of the reference center point of the light-shielding double-sided tape 16. The allowable range may be set with respect to the degree of coincidence between the coordinates of the center point of the light-shielding double-sided tape 16 and the coordinates of the reference center point of the light-shielding double-sided tape 16. For example, the control unit 25 may determine whether or not the coordinates of the center point of the light-shielding double-sided tape 16 match or are approximate to the coordinates of the reference center point of the light-shielding double-sided tape 16. In this case, the photographing and the position adjustment of the light-shielding double-sided tape 16 are repeated until the coordinates of the outline point of the light-shielding double-sided tape 16 coincide with or are approximate to the coordinates of the reference outline point of the light-shielding double-sided tape 16, and the coordinates of the center point of the light-shielding double-sided tape 16 coincide with or are approximate to the coordinates of the reference center point of the light-shielding double-sided tape 16.

In the step (a3) of fig. 5, the joining section 21 joins the prism sheet 15 and the light-shielding double-sided tape 16 by at least one of moving the prism sheet 15 in the thickness direction of the prism sheet 15 and moving the light-shielding double-sided tape 16 in the thickness direction of the light-shielding double-sided tape 16. For example, the attaching portion 21 may attach the prism sheet 15 to the light-shielding double-sided tape 16 by bringing the prism sheet 15 close to the light-shielding double-sided tape 16 in the thickness direction of the prism sheet 15. For example, the joining section 21 may join the prism sheet 15 and the light-shielding double-sided tape 16 by bringing the light-shielding double-sided tape 16 close to the prism sheet 15 in the thickness direction of the light-shielding double-sided tape 16.

In accordance with the steps (a1) to (A3) of fig. 5, the position of the prism sheet 15 and the position of the light-shielding double-sided tape 16 are adjusted to bond the prism sheet 15 and the light-shielding double-sided tape 16, and therefore, the accuracy of bonding the prism sheet 15 and the light-shielding double-sided tape 16 is improved. Accordingly, even when the width of the light-shielding double-sided tape 16 is small, the prism sheet 15 and the light-shielding double-sided tape 16 can be bonded with high accuracy, and the occurrence of light leakage in the surface light source device 1 can be suppressed while suppressing positional deviation between the bonded prism sheet 15 and the light-shielding double-sided tape 16.

Referring to fig. 5, an example in which the prism sheet 15 and the light-shielding double-sided tape 16 are bonded by adjusting the position of the prism sheet 15 and the position of the light-shielding double-sided tape 16 is described. Not limited to this example, the prism sheet 15 and the light-shielding double-sided tape 16 may be bonded to each other by adjusting the position of the light-shielding double-sided tape 16. Next, an example in which the prism sheet 15 and the light-shielding double-sided tape 16 are attached by adjusting the position of the light-shielding double-sided tape 16 will be described. In the step (a1) of fig. 5, the control unit 25 calculates the coordinates of the contour point and the coordinates of the center point of the prism sheet 15, and stores the calculated coordinates in the storage unit 26 as the coordinates of the reference contour point and the coordinates of the reference center point of the prism sheet 15. The other points of the step (a1) in fig. 5 are the same as those described above.

In the step (a2) of fig. 5, the control unit 25 calculates the coordinates of the contour point and the coordinates of the center point of the light-shielding double-sided tape 16, and stores the coordinates of the contour point and the coordinates of the center point of the light-shielding double-sided tape 16 in the storage unit 26. In the step (a2) of fig. 5, the control unit 25 corrects the coordinates of the contour point and the coordinates of the center point of the light-shielding double-sided tape 16 based on the coordinates of the reference contour point and the coordinates of the reference center point of the prism sheet 15, and stores the corrected coordinates in the storage unit 26 as the corrected coordinates of the contour point and the corrected coordinates of the center point of the light-shielding double-sided tape 16. In the step (a2) of fig. 5, the pasting section 21 adjusts the position of the center point of the light-shielding double-sided tape 16 so that the coordinates of the center point of the light-shielding double-sided tape 16 match the corrected coordinates of the center point of the light-shielding double-sided tape 16. In the step (a2) of fig. 5, the pasting unit 21 adjusts the position of the outline point of the light-shielding double-sided tape 16 so that the coordinate of the outline point of the light-shielding double-sided tape 16 matches the corrected coordinate of the outline point of the light-shielding double-sided tape 16. The other points of the step (a2) in fig. 5 are the same as those described above. The step (a3) in fig. 5 is the same as described above.

Fig. 8 is an explanatory diagram of a process of bonding the prism sheet 15 and the light-shielding double-sided tape 16. In the steps (B1) to (B3) in fig. 8, after the position of the light-shielding double-sided tape 16 is adjusted, the position of the prism sheet 15 is adjusted, and the prism sheet 15 and the light-shielding double-sided tape 16 are bonded to each other. In the example shown in fig. 8, the imaging unit 22 includes a plurality of cameras 31.

In the step (B1) in fig. 8, the attaching unit 21 positions the light-shielding double-sided tape 16 at a predetermined position with the light-shielding double-sided tape 16 held, and the camera 31 photographs the light-shielding double-sided tape 16 from the thickness direction of the light-shielding double-sided tape 16. In the example shown in fig. 8, the camera 31 photographs the light-shielding double-sided tape 16 from the lower surface side of the light-shielding double-sided tape 16. The lower surface of the light-shielding double-sided tape 16 is a contact surface of the light-shielding double-sided tape 16 with the prism sheet 15. The shot data of the light-shielding double-sided tape 16 shot by the camera 31 is stored in the storage section 26. For example, in the case where the light-shielding double-sided tape 16 has a frame shape having a quadrangular opening in a plan view, the four cameras 31 may capture images of respective regions of the light-shielding double-sided tape 16 including respective vertices of the quadrangular opening. Not limited to the example shown in fig. 8, one camera 31 may photograph the light-shielding double-sided tape 16. In the same manner as in the example shown in fig. 5, the control unit 25 calculates coordinates of a contour point and coordinates of a center point of the light-shielding double-sided tape 16, and the attaching unit 21 adjusts the position of the center point and the position of the contour point of the light-shielding double-sided tape 16. Further, as in the example shown in fig. 5, the photographing and the position adjustment of the light-shielding double-sided tape 16 are repeated until the coordinates of the outline point of the light-shielding double-sided tape 16 coincide with the coordinates of the reference outline point of the light-shielding double-sided tape 16 and the coordinates of the center point of the light-shielding double-sided tape 16 coincide with the coordinates of the reference center point of the light-shielding double-sided tape 16. In addition, similarly to the example shown in fig. 5, the photographing and the position adjustment of the light-shielding double-sided tape 16 may be repeated until the coordinates of the outline point of the light-shielding double-sided tape 16 coincide with or are approximate to the coordinates of the reference outline point of the light-shielding double-sided tape 16, and the coordinates of the center point of the light-shielding double-sided tape 16 coincide with or are approximate to the coordinates of the reference center point of the light-shielding double-sided tape 16.

In the step (B2) in fig. 8, the joining section 21 positions the prism sheet 15 at a predetermined position with the prism sheet 15 gripped, and the camera 31 photographs the prism sheet 15 from the thickness direction of the prism sheet 15. In the example shown in fig. 8, the prism sheet 15 is disposed so as to overlap the prism sheet 15 with the light-shielding double-sided tape 16. In the example shown in fig. 8, the camera 31 photographs the prism sheet 15 from the lower surface side of the prism sheet 15. The lower surface of the prism sheet 15 is opposite to the surface of the prism sheet 15 that is in contact with the light-shielding double-sided tape 16. The shot data of the prism sheet 15 shot by the camera 31 is stored in the storage section 26. In the same manner as in the example shown in fig. 5, the control unit 25 calculates the coordinates of the contour point and the coordinates of the center point of the prism sheet 15, and the pasting unit 21 adjusts the position of the center point and the position of the contour point of the prism sheet 15. Further, as in the example shown in fig. 5, the photographing of the prism sheet 15 and the adjustment of the position are repeated until the coordinates of the contour point of the prism sheet 15 coincide with the coordinates of the reference contour point of the prism sheet 15 and the coordinates of the center point of the prism sheet 15 coincide with the coordinates of the reference center point of the prism sheet 15. In the same manner as the example shown in fig. 5, the photographing of the prism sheet 15 and the adjustment of the position may be repeated until the coordinates of the contour point of the prism sheet 15 coincide with or are approximate to the coordinates of the reference contour point of the prism sheet 15 and the coordinates of the center point of the prism sheet 15 coincide with or are approximate to the coordinates of the reference center point of the prism sheet 15.

In the step (B3) of fig. 8, the joining section 21 joins the prism sheet 15 and the light-shielding double-sided tape 16 by at least one of moving the prism sheet 15 in the thickness direction of the prism sheet 15 and moving the light-shielding double-sided tape 16 in the thickness direction of the light-shielding double-sided tape 16.

In accordance with the steps (B1) to (B3) in fig. 8, the position of the prism sheet 15 and the position of the light-shielding double-sided tape 16 are adjusted to bond the prism sheet 15 and the light-shielding double-sided tape 16, and therefore, the accuracy of bonding the prism sheet 15 and the light-shielding double-sided tape 16 is improved. Accordingly, even when the width of the light-shielding double-sided tape 16 is small, the prism sheet 15 and the light-shielding double-sided tape 16 can be bonded with high accuracy, and the occurrence of light leakage in the surface light source device 1 can be suppressed while suppressing positional deviation between the bonded prism sheet 15 and the light-shielding double-sided tape 16.

Referring to fig. 8, an example in which the prism sheet 15 and the light-shielding double-sided tape 16 are bonded by adjusting the position of the prism sheet 15 and the position of the light-shielding double-sided tape 16 is described. Not limited to this example, the prism sheet 15 and the light-shielding double-sided tape 16 may be bonded to each other by adjusting the position of the light-shielding double-sided tape 16. Next, an example in which the prism sheet 15 and the light-shielding double-sided tape 16 are attached by adjusting the position of the light-shielding double-sided tape 16 will be described. In the step (B1) of fig. 8, the control unit 25 calculates the coordinates of the contour point and the coordinates of the center point of the light-shielding double-sided tape 16, and stores the calculated coordinates in the storage unit 26 as the coordinates of the reference contour point and the coordinates of the reference center point of the light-shielding double-sided tape 16. The other points of the step (B1) in fig. 8 are the same as those described above.

In the step (B2) of fig. 8, the control unit 25 calculates the coordinates of the contour point and the coordinates of the center point of the prism sheet 15, and stores the coordinates of the contour point and the coordinates of the center point of the prism sheet 15 in the storage unit 26. In the step (B2) of fig. 8, the control unit 25 corrects the coordinates of the contour point and the coordinates of the center point of the prism sheet 15 based on the coordinates of the reference contour point and the coordinates of the reference center point of the light-shielding double-sided tape 16, and stores the corrected coordinates in the storage unit 26 as the corrected coordinates of the contour point and the corrected coordinates of the center point of the prism sheet 15. In the step (B2) of fig. 8, the pasting unit 21 adjusts the position of the center point of the prism sheet 15 so that the coordinates of the center point of the prism sheet 15 match the corrected coordinates of the center point of the prism sheet 15. In the step (B2) of fig. 8, the pasting unit 21 adjusts the positions of the contour points of the prism sheet 15 so that the coordinates of the contour points of the prism sheet 15 match the corrected coordinates of the contour points of the prism sheet 15. The other points of the step (B2) in fig. 8 are the same as those described above. The step (B3) in fig. 8 is the same as described above.

The example shown in fig. 5 may be combined with the example shown in fig. 8. For example, the plurality of cameras 31 may be disposed on the upper surface side of the prism sheet 15 and the upper surface side of the light-shielding double-sided tape 16, and the plurality of cameras 31 may be disposed on the lower surface side of the prism sheet 15 and the lower surface side of the light-shielding double-sided tape 16. The plurality of cameras 31 may image the prism sheet 15 from the upper surface side of the prism sheet 15 and image the prism sheet 15 from the lower surface side of the prism sheet 15. The plurality of cameras 31 may photograph the light-shielding double-sided tape 16 from the upper surface side of the light-shielding double-sided tape 16 and photograph the light-shielding double-sided tape 16 from the lower surface side of the light-shielding double-sided tape 16.

Fig. 9 is an explanatory diagram of a process of attaching the light-shielding double-sided tape 16 to which the prism sheet 15 is attached to the frame 13. In the steps (C1) to (C3) in fig. 9, after the position of the frame 13 is adjusted, the position of the light-shielding double-sided tape 16 to which the prism sheet 15 is attached is adjusted, and the light-shielding double-sided tape 16 to which the prism sheet 15 is attached to the frame 13. In the example shown in fig. 9, the imaging unit 24 includes a plurality of cameras 32. In the example shown in fig. 9, the frame 13 is a frame body surrounding the side surface of the light guide plate 11. The frame 13 is not limited to the example shown in fig. 9, and may be a case having a frame body surrounding the side surface of the light guide plate 11 and a bottom plate on which the frame body is erected. In the example shown in fig. 9, the light guide plate 11, the light source 12, the diffusion sheet 14, the FPC17, and the fixing member 18 are housed in the frame 13, and the reflective sheet 19 is attached to the bottom of the frame 13 via the adhesive layer 40. In fig. 9, the light source 12, the FPC17, and the fixing member 18 are not shown.

In the step (C1) in fig. 9, the attachment portion 23 positions the frame 13 at a predetermined position with the frame 13 gripped, and the camera 32 photographs the frame 13 from the thickness direction of the frame 13. In the example shown in fig. 9, the camera 32 photographs the frame 13 from the upper surface side of the frame 13. The upper surface of the frame 13 is a contact surface of the frame 13 with the light-shielding double-sided tape 16, and faces the same direction as the light exit surface of the light guide plate 11. The shooting data of the frame 13 shot by the camera 32 is stored in the storage section 26. For example, when the outer peripheral portion of the frame 13 is a quadrangle in a plan view (as viewed from the normal direction of the upper surface of the frame 13), the four cameras 32 may capture images of regions including vertices of the quadrangle in the outer peripheral portion of the frame 13. Not limited to the example shown in fig. 9, one camera 32 may photograph the frame 13.

The control unit 25 acquires the image data of the frame 13 from the storage unit 26, and calculates the coordinates of the contour points of the frame 13 in accordance with the shape of the frame 13. For example, when the outer peripheral portion of the frame 13 is a quadrangle in a plan view, the coordinates of the contour points of the frame 13 may be the coordinates of the vertices of the quadrangle at the outer peripheral portion of the frame 13. The control unit 25 calculates coordinates of the center point of the frame 13 from the coordinates of the contour points of the frame 13. The control unit 25 may calculate an average value of the coordinates of the plurality of contour points of the frame 13 as the coordinates of the center point of the frame 13. For example, when the outer peripheral portion of the frame 13 is a quadrangle in a plan view, the coordinates of the center point of the frame 13 may be an average of the coordinates of the vertices of the quadrangle at the outer peripheral portion of the frame 13. The storage unit 26 stores coordinates of the reference contour point of the frame 13 and coordinates of the reference center point of the frame 13 in advance. The coordinates of the reference contour point and the coordinates of the reference center point of the frame 13 are coordinates for accurately positioning the frame 13 at a predetermined position. The attaching portion 23 adjusts the position of the center point of the frame 13 so that the coordinates of the center point of the frame 13 coincide with the coordinates of the reference center point of the frame 13. The attachment portion 23 adjusts the position of the center point of the frame 13 by moving the frame 13 in the plane direction of the frame 13. The pasting unit 23 adjusts the position of the contour point of the frame 13 so that the coordinates of the contour point of the frame 13 match the coordinates of the reference contour point of the frame 13. The attaching portion 23 adjusts the position of the contour point of the frame 13 by moving the frame 13 in the plane direction of the frame 13. The planar direction of the frame 13 is orthogonal to the thickness direction of the frame 13. The position of the contour point of the frame 13 may be adjusted by the same method as the position adjustment of the contour point of the prism sheet 15 shown in fig. 6 and 7.

After adjusting the position of the center point and the position of the contour point of the frame 13, the camera 32 images the frame 13, and the control unit 25 calculates the coordinates of the contour point and the coordinates of the center point of the frame 13. The control unit 25 determines whether or not the coordinates of the contour point of the frame 13 match the coordinates of the reference contour point of the frame 13. The control unit 25 determines whether or not the coordinates of the center point of the frame 13 match the coordinates of the reference center point of the frame 13. When the coordinates of the contour point of the frame 13 coincide with the coordinates of the reference contour point of the frame 13 and the coordinates of the center point of the frame 13 coincide with the coordinates of the reference center point of the frame 13, the process proceeds to step (C2) of fig. 9. On the other hand, when the coordinates of the contour points of the frame 13 do not match the coordinates of the reference contour points of the frame 13, or when the coordinates of the center point of the frame 13 do not match the coordinates of the reference center point of the frame 13, the pasting unit 23 adjusts the position of the center point of the frame 13 and the position of the contour points again. In this way, the photographing and the position adjustment of the frame 13 are repeated until the coordinates of the contour point of the frame 13 coincide with the coordinates of the reference contour point of the frame 13 and the coordinates of the center point of the frame 13 coincide with the coordinates of the reference center point of the frame 13.

The allowable range may be set with respect to the degree of coincidence between the coordinates of the contour point of the frame 13 and the coordinates of the reference contour point of the frame 13. For example, the control unit 25 may determine whether or not the coordinates of the center point of the frame 13 match or are approximate to the coordinates of the reference center point of the frame 13. The allowable range may be set with respect to the degree of coincidence between the coordinates of the center point of the frame 13 and the coordinates of the reference center point of the frame 13. For example, the control unit 25 may determine whether or not the coordinates of the center point of the frame 13 match or are approximate to the coordinates of the reference center point of the frame 13. In this case, the imaging of the frame 13 and the adjustment of the position are repeated until the coordinates of the contour point of the frame 13 coincide with or are approximate to the coordinates of the reference contour point of the frame 13 and the coordinates of the center point of the frame 13 coincide with or are approximate to the coordinates of the reference center point of the frame 13.

In the step (C2) of fig. 9, the attaching portion 23 positions the light-shielding double-sided tape 16 with the prism sheet 15 attached thereto held, and the camera 32 photographs the light-shielding double-sided tape 16 from the thickness direction of the light-shielding double-sided tape 16. In the example shown in fig. 9, the light-shielding double-sided tape 16 is disposed so that the frame 13 overlaps the light-shielding double-sided tape 16. In the example shown in fig. 9, the camera 32 photographs the light-shielding double-sided tape 16 from the upper surface side of the light-shielding double-sided tape 16. The upper surface of the light-shielding double-sided adhesive tape 16 faces in the same direction as the upper surface of the frame 13. The shot data of the light-shielding double-sided tape 16 shot by the camera 32 is stored in the storage section 26.

In the same manner as in the example shown in fig. 5, the control unit 25 calculates coordinates of the contour point and coordinates of the center point of the light-shielding double-sided tape 16, and the attaching unit 23 adjusts the position of the center point and the position of the contour point of the light-shielding double-sided tape 16. For example, when the light-shielding double-sided tape 16 has a frame shape having a quadrangular opening in a plan view, the coordinates of the contour points of the light-shielding double-sided tape 16 may be the coordinates of the vertices of the quadrangle of the opening of the light-shielding double-sided tape 16. For example, when the outer peripheral portion of the light-shielding double-sided tape 16 is a quadrangle in a plan view, the coordinates of the contour points of the light-shielding double-sided tape 16 may be the coordinates of the vertices of the quadrangle at the outer peripheral portion of the light-shielding double-sided tape 16. Further, as in the example shown in fig. 5, the photographing and the position adjustment of the light-shielding double-sided tape 16 are repeated until the coordinates of the outline point of the light-shielding double-sided tape 16 coincide with the coordinates of the reference outline point of the light-shielding double-sided tape 16 and the coordinates of the center point of the light-shielding double-sided tape 16 coincide with the coordinates of the reference center point of the light-shielding double-sided tape 16. In addition, similarly to the example shown in fig. 5, the photographing and the position adjustment of the light-shielding double-sided tape 16 may be repeated until the coordinates of the outline point of the light-shielding double-sided tape 16 coincide with or are approximate to the coordinates of the reference outline point of the light-shielding double-sided tape 16, and the coordinates of the center point of the light-shielding double-sided tape 16 coincide with or are approximate to the coordinates of the reference center point of the light-shielding double-sided tape 16.

In the step (C3) of fig. 9, the joining section 23 joins the light-shielding double-sided tape 16 to which the prism sheet 15 is joined to the frame 13 by at least one of the movement of the frame 13 in the thickness direction of the frame 13 and the movement of the light-shielding double-sided tape 16 in the thickness direction of the light-shielding double-sided tape 16. For example, the attaching portion 23 may attach the frame 13 and the light-shielding double-sided tape 16 by bringing the light-shielding double-sided tape 16 close to the frame 13 in the thickness direction of the light-shielding double-sided tape 16. For example, the attaching portion 23 may attach the frame 13 and the light-shielding double-sided tape 16 by bringing the frame 13 close to the light-shielding double-sided tape 16 in the thickness direction of the frame 13. The surface light source device 1 can be manufactured by bonding the light-shielding double-sided tape 16 to which the prism sheet 15 is bonded to the frame 13.

When the prism sheet 15 is displaced in the planar direction of the prism sheet 15 when the frame 13 and the light-shielding double-sided tape 16 are bonded, the prism sheet 15 may be placed on the upper surface of the frame 13. In the case where a stepped surface is formed at the inner peripheral portion of the frame 13, the upper surface of the frame 13 is higher than the stepped surface formed at the inner peripheral portion of the frame 13. The control unit 25 may determine whether or not the prism sheet 15 is in contact with the upper surface of the frame 13 based on the image data of the frame 13, the image data of the prism sheet 15, and the image data of the light-shielding double-sided tape 16. The attaching portion 23 adjusts at least one of the position of the frame 13 and the position of the light-shielding double-sided tape 16 in accordance with the determination result of the control portion 25. This can prevent the prism sheet 15 from being placed on the upper surface of the frame 13 when the frame 13 and the light-shielding double-sided tape 16 are bonded together.

In accordance with the steps (C1) to (C3) in fig. 9, since the position of the frame 13 and the position of the light-shielding double-sided tape 16 are adjusted to bond the frame 13 and the light-shielding double-sided tape 16, the bonding accuracy between the frame 13 and the light-shielding double-sided tape 16 is improved. Thus, even when the width of the frame 13 is small or when the width of the light-shielding double-sided tape 16 is small, the light-shielding double-sided tape 16 can be attached to the frame 13 with high accuracy, and the positional deviation between the attached frame 13 and the light-shielding double-sided tape 16 can be suppressed. Further, since the prism sheet 15 is placed on the diffusion sheet 14 by attaching the frame 13 and the light-shielding double-sided tape 16, the accuracy of the position where the prism sheet 15 is placed on the diffusion sheet 14 can be improved, and the deviation of the position where the prism sheet 15 is placed on the diffusion sheet 14 can be suppressed. Since the deviation of the position where the prism sheet 15 is placed on the diffusion sheet 14 and the deviation of the position where the light-shielding double-sided tape 16 is pasted can be suppressed, the occurrence of light leakage in the surface light source device 1 can be suppressed.

Referring to fig. 9, an example in which the frame 13 and the light-shielding double-sided tape 16 are attached by adjusting the position of the frame 13 and the position of the light-shielding double-sided tape 16 will be described. Not limited to this example, the frame 13 may be attached to the light-shielding double-sided tape 16 by adjusting the position of the light-shielding double-sided tape 16. Next, an example of attaching the frame 13 and the light-shielding double-sided tape 16 by adjusting the position of the light-shielding double-sided tape 16 will be described. In the step (C1) of fig. 9, the control unit 25 calculates the coordinates of the contour point and the coordinates of the center point of the frame 13, and stores the calculated coordinates in the storage unit 26 as the coordinates of the reference contour point and the coordinates of the reference center point of the frame 13. The other points of the step (C1) in fig. 9 are the same as those described above.

In the step (C2) of fig. 9, the control unit 25 calculates the coordinates of the contour point and the coordinates of the center point of the light-shielding double-sided tape 16, and stores the coordinates of the contour point and the coordinates of the center point of the light-shielding double-sided tape 16 in the storage unit 26. In the step (C2) of fig. 9, the control unit 25 corrects the coordinates of the contour point and the coordinates of the center point of the light-shielding double-sided tape 16 based on the coordinates of the reference contour point and the coordinates of the reference center point of the frame 13, and stores the corrected coordinates in the storage unit 26 as the corrected coordinates of the contour point and the corrected coordinates of the center point of the light-shielding double-sided tape 16. In the step (C2) of fig. 9, the pasting section 21 adjusts the position of the center point of the light-shielding double-sided tape 16 so that the coordinates of the center point of the light-shielding double-sided tape 16 match the corrected coordinates of the center point of the light-shielding double-sided tape 16. In the step (C2) of fig. 9, the pasting unit 21 adjusts the position of the outline point of the light-shielding double-sided tape 16 so that the coordinate of the outline point of the light-shielding double-sided tape 16 matches the corrected coordinate of the outline point of the light-shielding double-sided tape 16. The other points of the step (C2) in fig. 9 are the same as those described above. The step (C3) in fig. 9 is the same as described above.

Fig. 10 is an explanatory diagram of a process of attaching the light-shielding double-sided tape 16 to which the prism sheet 15 is attached to the frame 13. In the steps (D1) to (D3) in fig. 10, after the position of the light-shielding double-sided tape 16 to which the prism sheet 15 is attached is adjusted, the position of the frame 13 is adjusted, and the light-shielding double-sided tape 16 to which the prism sheet 15 is attached to the frame 13. In the example shown in fig. 10, the imaging unit 24 includes a plurality of cameras 32. In the example shown in fig. 10, the frame 13 is a case having a frame body surrounding the side surface of the light guide plate 11 and a bottom plate on which the frame body is erected. In the example shown in fig. 10, the light guide plate 11, the light source 12, the diffusion sheet 14, the FPC17, the fixing member 18, and the reflective sheet 19 are housed in the frame 13. In fig. 10, the light source 12, the FPC17, and the fixing member 18 are not shown. The frame 13 is not limited to the example shown in fig. 10, and may be a frame body surrounding the side surface of the light guide plate 11. When the frame 13 is a frame body surrounding the side surface of the light guide plate 11, the frame 13 is imaged by the camera 32 by making the size of the reflective sheet 19 smaller than the size of the frame 13.

In the step (D1) of fig. 10, the attaching part 23 positions the light-shielding double-sided tape 16 with the prism sheet 15 attached thereto held, and the camera 32 photographs the light-shielding double-sided tape 16 from the thickness direction of the light-shielding double-sided tape 16. In the example shown in fig. 10, the camera 32 photographs the light-shielding double-sided tape 16 from the lower surface side of the light-shielding double-sided tape 16. The shot data of the light-shielding double-sided tape 16 shot by the camera 32 is stored in the storage section 26. For example, in the case where the outer peripheral portion of the light-shielding double-sided tape 16 is a quadrangle in a plan view, the four cameras 32 may capture images of regions including vertices of the quadrangle in the outer peripheral portion of the light-shielding double-sided tape 16. Not limited to the example shown in fig. 10, one camera 32 may photograph the light-shielding double-sided tape 16.

In the same manner as in the example shown in fig. 5, the control unit 25 calculates coordinates of a contour point and coordinates of a center point of the light-shielding double-sided tape 16, and the attaching unit 21 adjusts the position of the center point and the position of the contour point of the light-shielding double-sided tape 16. For example, when the outer peripheral portion of the light-shielding double-sided tape 16 is a quadrangle in a plan view, the coordinates of the contour points of the light-shielding double-sided tape 16 may be the coordinates of the vertices of the quadrangle at the outer peripheral portion of the light-shielding double-sided tape 16. Further, as in the example shown in fig. 5, the photographing and the position adjustment of the light-shielding double-sided tape 16 are repeated until the coordinates of the outline point of the light-shielding double-sided tape 16 coincide with the coordinates of the reference outline point of the light-shielding double-sided tape 16 and the coordinates of the center point of the light-shielding double-sided tape 16 coincide with the coordinates of the reference center point of the light-shielding double-sided tape 16. In addition, similarly to the example shown in fig. 5, the photographing and the position adjustment of the light-shielding double-sided tape 16 may be repeated until the coordinates of the outline point of the light-shielding double-sided tape 16 coincide with or are approximate to the coordinates of the reference outline point of the light-shielding double-sided tape 16, and the coordinates of the center point of the light-shielding double-sided tape 16 coincide with or are approximate to the coordinates of the reference center point of the light-shielding double-sided tape 16.

In the step (D2) in fig. 10, the attachment portion 23 positions the frame 13 at a predetermined position with the frame 13 gripped, and the camera 32 photographs the frame 13 from the thickness direction of the frame 13. In the example shown in fig. 10, the frame 13 is disposed so as to overlap the light-shielding double-sided tape 16 with the frame 13. In the example shown in fig. 10, the camera 32 photographs the frame 13 from the lower surface side of the frame 13. The lower surface of the frame 13 is the opposite surface of the frame 13 from the surface in contact with the light-shielding double-sided tape 16. The shooting data of the frame 13 shot by the camera 32 is stored in the storage section 26. For example, when the outer peripheral portion of the frame 13 is a quadrangle as viewed from the normal direction of the lower surface of the frame 13, the four cameras 32 may capture images of regions including vertices of the quadrangle on the outer peripheral portion of the frame 13. Not limited to the example shown in fig. 10, one camera 32 may photograph the frame 13.

In the same manner as in the example shown in fig. 9, the control unit 25 calculates the coordinates of the contour point and the coordinates of the center point of the frame 13, and the pasting unit 23 adjusts the position of the center point and the position of the contour point of the frame 13. For example, when the outer periphery of the frame 13 is a quadrangle when viewed from the normal direction of the lower surface of the frame 13, the coordinates of the contour points of the frame 13 may be the coordinates of the vertices of the quadrangle on the outer periphery of the frame 13. Further, as in the example shown in fig. 9, the photographing of the frame 13 and the adjustment of the position are repeated until the coordinates of the contour point of the frame 13 coincide with the coordinates of the reference contour point of the frame 13 and the coordinates of the center point of the frame 13 coincide with the coordinates of the reference center point of the frame 13. In the same manner as the example shown in fig. 9, the photographing of the frame 13 and the adjustment of the position may be repeated until the coordinates of the contour point of the frame 13 coincide with or are approximate to the coordinates of the reference contour point of the frame 13 and the coordinates of the center point of the frame 13 coincide with or are approximate to the coordinates of the reference center point of the frame 13.

In the step (D3) of fig. 10, the joining section 23 joins the light-shielding double-sided tape 16 to which the prism sheet 15 is joined to the frame 13 by at least one of the movement of the frame 13 in the thickness direction of the frame 13 and the movement of the light-shielding double-sided tape 16 in the thickness direction of the light-shielding double-sided tape 16. For example, the attaching portion 23 may attach the frame 13 and the light-shielding double-sided tape 16 by bringing the light-shielding double-sided tape 16 close to the frame 13 in the thickness direction of the light-shielding double-sided tape 16. For example, the attaching portion 23 may attach the frame 13 and the light-shielding double-sided tape 16 by bringing the frame 13 close to the light-shielding double-sided tape 16 in the thickness direction of the frame 13. The surface light source device 1 is manufactured by bonding the light-shielding double-sided tape 16 to which the prism sheet 15 is bonded to the frame 13.

In accordance with the steps (D1) to (D3) in fig. 10, the position of the frame 13 and the position of the light-shielding double-sided tape 16 are adjusted to bond the frame 13 and the light-shielding double-sided tape 16, so that the bonding accuracy between the frame 13 and the light-shielding double-sided tape 16 is improved. Thus, even when the width of the frame 13 is small or when the width of the light-shielding double-sided tape 16 is small, the light-shielding double-sided tape 16 can be attached to the frame 13 with high accuracy, and the positional deviation between the attached frame 13 and the light-shielding double-sided tape 16 can be suppressed. Further, since the prism sheet 15 is placed on the diffusion sheet 14 by attaching the frame 13 and the light-shielding double-sided tape 16, the accuracy of the position of placing the prism sheet 15 on the diffusion sheet 14 is improved, and the position of placing the prism sheet 15 on the diffusion sheet 14 can be prevented from being deviated. Since the deviation of the position where the prism sheet 15 is placed on the diffusion sheet 14 and the deviation of the position where the light-shielding double-sided tape 16 is pasted can be suppressed, the occurrence of light leakage in the surface light source device 1 can be suppressed.

Referring to fig. 10, an example in which the frame 13 and the light-shielding double-sided tape 16 are attached by adjusting the position of the frame 13 and the position of the light-shielding double-sided tape 16 will be described. Not limited to this example, the frame 13 and the light-shielding double-sided tape 16 may be attached to each other by adjusting the position of the frame 13. Next, an example of attaching the frame 13 and the light-shielding double-sided tape 16 by adjusting the position of the frame 13 will be described. In the step (D1) of fig. 10, the control unit 25 calculates the coordinates of the contour point and the coordinates of the center point of the light-shielding double-sided tape 16, and stores the calculated coordinates in the storage unit 26 as the coordinates of the reference contour point and the coordinates of the reference center point of the light-shielding double-sided tape 16. The other points of the step (D1) in fig. 10 are the same as those described above.

In the step (D2) of fig. 10, the control unit 25 calculates the coordinates of the contour point and the coordinates of the center point of the frame 13, and stores the coordinates of the contour point and the coordinates of the center point of the frame 13 in the storage unit 26. In the step (D2) of fig. 10, the control unit 25 corrects the coordinates of the contour point and the coordinates of the center point of the frame 13 based on the coordinates of the reference contour point and the coordinates of the reference center point of the light-shielding double-sided tape 16, and stores the corrected coordinates in the storage unit 26 as the corrected coordinates of the contour point and the corrected coordinates of the center point of the frame 13. In the step (D2) of fig. 10, the attaching unit 21 adjusts the position of the center point of the frame 13 so that the coordinates of the center point of the frame 13 match the corrected coordinates of the center point of the frame 13. In the step (D2) of fig. 10, the pasting unit 21 adjusts the position of the contour point of the frame 13 so that the coordinate of the contour point of the frame 13 matches the corrected coordinate of the contour point of the frame 13. The other points of the step (D2) in fig. 10 are the same as those described above. The step (D3) in fig. 10 is the same as described above.

The example shown in fig. 9 may be combined with the example shown in fig. 10. For example, the plurality of cameras 32 may be disposed on the upper surface side of the frame 13 and the upper surface side of the light-shielding double-sided tape 16 to which the prism sheet 15 is attached, and the plurality of cameras 31 may be disposed on the lower surface side of the frame 13 and the lower surface side of the light-shielding double-sided tape 16 to which the prism sheet 15 is attached. The plurality of cameras 32 may also image the frame 13 from the upper surface side of the frame 13 and image the prism sheet 15 from the lower surface side of the frame 13. The plurality of cameras 32 may photograph the light-shielding double-sided tape 16 from the upper surface side of the light-shielding double-sided tape 16 to which the prism sheet 15 is attached, and photograph the light-shielding double-sided tape 16 from the lower surface side of the light-shielding double-sided tape 16 to which the prism sheet 15 is attached.

Fig. 11 is a plan view of the surface light source device 1 of the exemplary embodiment. A broken line B of fig. 11 is a center line of the surface light source device 1. A broken line C of fig. 11 is a line passing through one side of the opening of the light-shielding double-sided tape 16, and a broken line D of fig. 11 is a line passing through the other side of the opening of the light-shielding double-sided tape 16. According to the surface light source device 1 manufactured by the manufacturing system 20 of the embodiment, the interval G1-the interval G2 of ± 0.05mm can be realized for the interval G1 of the broken line B and the broken line C and the interval G2 of the broken line B and the broken line D, for example.

Description of the reference numerals

1 a surface light source device; 2 a display panel; 3, a frame; 11 a light guide plate; 12 light source; 13 a frame; 14 a diffuser sheet; 15 a prismatic sheet; 16 light-shielding double-sided adhesive tape; 17 FPC; 18 a fixing member; 19 a reflective sheet; 20 a manufacturing system; 21, 23 pasting parts; 22, 24 shooting parts; 25 a control unit; 26 a storage unit; 31, 32 cameras.

Claims (7)

1. A system for manufacturing a surface light source device, comprising:

a first bonding section that bonds the prism sheet to the light-shielding tape;

a first imaging unit that images the light-shielding tape to which the prism sheet is attached from a thickness direction of the light-shielding tape, and images the frame surrounding a side surface of the light guide plate and accommodating the light guide plate from a thickness direction of the frame;

a calculating unit that calculates coordinates of a contour point and coordinates of a center point of the light-shielding tape from imaging data of the light-shielding tape to which the prism sheet is attached, and calculates coordinates of a contour point and coordinates of a center point of the frame from imaging data of the frame;

and a second bonding part which adjusts at least one of a position of the light-shielding tape to which the prism sheet is bonded and a position of the frame based on coordinates of the contour point and the center point of the light-shielding tape and coordinates of the contour point and the center point of the frame, and bonds the light-shielding tape to which the prism sheet is bonded and the frame.

2. The manufacturing system of the surface light source device as set forth in claim 1,

a second imaging unit that images the prism sheet from a thickness direction of the prism sheet and images the light shielding tape from a thickness direction of the light shielding tape,

the calculating unit calculates coordinates of a contour point and coordinates of a center point of the prism sheet from the imaging data of the prism sheet, and calculates coordinates of a contour point and coordinates of a center point of the light-shielding tape from the imaging data of the light-shielding tape,

the first pasting unit adjusts at least one of the position of the prism sheet and the position of the light-shielding tape based on the coordinates of the contour point and the coordinates of the center point of the prism sheet and the coordinates of the center point and the coordinates of the contour point of the light-shielding tape, and pastes the prism sheet and the light-shielding tape.

3. The manufacturing system of the surface light source device as set forth in claim 2,

the second imaging unit images the prism sheet, and then images the light-shielding tape in a state where the light-shielding tape is disposed so as to overlap the prism sheet with the light-shielding tape.

4. The manufacturing system of the surface light source device as set forth in claim 2,

the second imaging unit images the prism sheet in a state where the prism sheet is arranged so that the light-shielding tape and the prism sheet overlap each other after the light-shielding tape is imaged.

5. The manufacturing system of the surface light source device as claimed in any one of claims 1 to 4,

the first imaging unit images the frame, and then images the light-shielding tape to which the prism sheet is attached in a state where the light-shielding tape to which the prism sheet is attached is arranged so as to overlap the frame.

6. The manufacturing system of the surface light source device as claimed in any one of claims 1 to 4,

the first imaging unit images the frame in a state where the light-shielding tape to which the prism sheet is attached is placed on the frame so as to overlap the light-shielding tape to which the prism sheet is attached.

7. A method for manufacturing a surface light source device, comprising:

a first bonding step of bonding the prism sheet to the light-shielding tape;

an imaging step of imaging the light-shielding tape to which the prism sheet is attached from a thickness direction of the light-shielding tape, and imaging the frame surrounding a side surface of a light guide plate and accommodating the light guide plate from a thickness direction of the frame;

a calculating step of calculating coordinates of a contour point and coordinates of a center point of the light-shielding tape from the image data of the light-shielding tape to which the prism sheet is attached, and calculating coordinates of a contour point and coordinates of a center point of the frame from the image data of the frame;

and a second bonding step of adjusting at least one of a position of the light-shielding tape to which the prism sheet is bonded and a position of the frame based on coordinates of the contour point and the center point of the light-shielding tape and coordinates of the contour point and the center point of the frame, and bonding the light-shielding tape to which the prism sheet is bonded and the frame.

Images