JP2000019495A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease stress that chips generate in glass and to prevent the unequal luminance of the glass by adopting such an array that the two segments connecting the centers of the joint surfaces of the two chips adjacent to each other do not exist on the same straight line for the array of the respective chips joined to the glass. SOLUTION: Such array that the two segments connecting the centers of the joint surfaces of the two chips adjacent to the chips do not exist on the same straight line is adopted for the array of the respective chips joined to the glass. Namely, the elongated chips 1a, 1b are arranged on the neighborhood of the two sides on the circumference the glass 2 in such a manner that their positions are offset from the adjacent chips. A polarizing plate 4a and the glass 3 are adhered to both surfaces of the glass 2. The stresses of the glass assume a distribution that the stresses increase at the ends of the chips but the ends of the adjacent chips 1a, 1b stagger and, therefore, the occurrence of the superposition of the stresses generated by both chips 1a, 1b is averted and the occurrence of the unequal luminance in the glass 2 is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device having no luminance unevenness.

[0002]

2. Description of the Related Art An example of a conventional liquid crystal display device is shown in FIG. In the conventional liquid crystal display device, an elongated chip 1 is connected near two sides around a glass 2, and the mutual positions of the chips are arranged such that the chips are arranged in a line in the longitudinal direction. Although this sequence is slightly different from the object of the present invention in the production method, for example,
Supervised by Honda, Multi-chip mounting technology, 1991,
It is used in the liquid crystal display device shown in Photo 4 on page 319 issued by Trikeps Corporation. The polarizing plate 4a and the glass 3 are bonded to both surfaces of the glass 2. In order to show the structure more clearly, a cross section along line 5 is shown in FIG.

In FIG. 3, a liquid crystal 8 is held between glass 2 and glass 3, and polarizing plates 4a and 4b are adhered to the surface of the glass. On the surface of glass 2, bump 6 of chip 1
Are connected and fixed with a thermosetting adhesive 7. The method of connecting the chip 1 is a method in which a heated jig is pressed against the chip 1 and the thermosetting adhesive 7 is thermoset.

[0004] This connection method is shown, for example, in FIG. 12 on page 291 of Honda Supervision, Multi-Chip Mounting Technology, published by Trikeps Corporation in 1991. Since the chip 1 thermally shrinks in a cooling process after the adhesive is cured, the chip 1 generates stress on the glass 2. FIGS. 4A and 4B are enlarged views of the chip connecting portion of FIG. The stress of the glass has an increasing distribution at the edge of the chip. As shown in FIGS. 4A and 4B, when the ends of adjacent chips are close to each other, the stress generated by both chips is superimposed, and the stress further increases at the portion 9.

Returning to FIG. 3, the function of the liquid crystal display will be described. The light radiated from the upper part of FIG. 3 passes through the polarizing plate 4a and becomes polarized. Then, when passing through the liquid crystal, the polarization plane changes according to the optical axis of the liquid crystal changed according to the driving signal of the chip. Since the lower polarizing plate 4b is orthogonal to the upper polarizing plate 4a,
Without a drive signal, the display remains dark, and the greater the change in the plane of polarization due to the liquid crystal, the higher the brightness of the display.

Referring again to FIGS. 4 (a) and 4 (b). As described above, when a portion 9 having high stress occurs in the glass, the polarization plane of polarized light passing through the glass changes due to the photoelastic effect of the glass. Therefore, a bright portion is formed in the portion 10 even when there is no drive signal for the chip. This is called luminance unevenness.

[0007]

It is necessary to prevent luminance unevenness in order to make an actual image unclear.

An object of the present invention is to prevent such uneven brightness.

[0009]

SUMMARY OF THE INVENTION The above object is achieved by reducing the stress generated on the glass by the chip. In particular, the stress of glass increases due to the superposition of stress when the distance between adjacent chip ends is small. For this reason, stress can be reduced by increasing the interval between the ends of adjacent chips. For this purpose, there is a trivial method such as using a chip having a short length and widening the interval between chips. However, this requires an increase in the degree of integration of the chip, which is not easy. The present invention has found a method of reducing stress by using the same chip as the conventional one and devising the arrangement.

In this method, the arrangement of each chip bonded to the glass is such that two line segments connecting the bonding surface of each chip and the center of the bonding surface of two chips adjacent to this chip do not exist on the same straight line. The chips are arranged so that they are arranged in a simple manner.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a liquid crystal display device according to the present invention will be described below with reference to FIG. In the liquid crystal display device of the present invention, elongated chips 1a and 1b are arranged near two sides of the glass 2 so as to be displaced from adjacent chips. Polarizing plates 4a on both sides of glass 2
And the glass 3 are bonded. In order to show the structure more clearly, FIGS. 5A and 5B show cross sections along lines 5a and 5b. 5A and 5B, the liquid crystal 8 is held between the glass 2 and the glass 3, and the polarizing plates 4a and 4a are provided on the surface of the glass.
b is adhered. The bumps 6 of the chip 1 are connected to the surface of the glass 2 and are fixed with a thermosetting adhesive 7.

In FIGS. 5 (a) and 5 (b), the chips 1 are arranged so that the positions thereof are different from each other. FIGS. 6A and 6B show FIG.
FIG. 4 is an enlarged view of a chip connection part of FIG. The stress of the glass has a distribution that increases at the end 9 of the chip, but since the ends of the adjacent chips are staggered, the stress generated by both chips does not overlap and the portion 9 does not overlap. There is no luminance unevenness.

[0013]

According to the present invention, the stress generated in the glass by the chip can be reduced, and the luminance unevenness of the glass can be prevented.

[Brief description of the drawings]

FIG. 1 is a plan view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a plan view of a conventional liquid crystal display device.

FIG. 3 is a partially enlarged sectional view of a liquid crystal display device according to one embodiment of the present invention.

FIGS. 4A and 4B are a plan view and a front view showing luminance unevenness of a conventional liquid crystal display device.

FIGS. 5A and 5B are partially enlarged cross-sectional views of a liquid crystal display device according to one embodiment of the present invention.

FIGS. 6A and 6B are a plan view and a front view showing a stress generation position of the liquid crystal display device according to one embodiment of the present invention.

[Explanation of symbols]

1a, 1b: semiconductor chip, 2, 3: glass, 4a, 4
b: polarizing plate, 5a, 5b: line, 6: bump, 7: thermosetting resin, 8: liquid crystal, 9: stress generating portion, 10: uneven brightness portion.

Claims (1)

[Claims] 1. A liquid crystal display in which a liquid crystal is held between two glasses and a surface of the glass and a surface of a plurality of semiconductor chips facing the surface are bonded with a thermosetting resin. Are arranged so that two line segments connecting the center of the bonding surface of each chip and the bonding surface of two chips adjacent to this chip do not exist on the same straight line. apparatus.