Method for leveling bent plastic flat plate

Abstract

The invention discloses a method flattening a bent plastic slab. The invention is characterized in that the invention comprises the following steps: (1) the plastic slabs to be processed are orderly piled from bottom to top with the piling type that the plastic slabs in odd number positions are taken as a group and the plastic slabs in even number positions are taken as the other group by counting from bottom to top; wherein, the concave surfaces of one group plastic slabs face upwards and the concave surfaces of the other group plastic slabs face downwards; adjacent plastic slabs are piled in symmetrical type; a concave surface gap is formed between opposite concave surfaces; in the piling process, liquid is added in the concave surface gap; (2) the piling state is kept, and the plastic slabs to be processed are pressed by virtue of gravity; (3) the levelness of the plastic slabs is detected; the plastic slabs with the levelness reaching the requirement are taken away and the residual plastic slabs are continued to be pressed, thus flattening the bent plastic slabs. The method can lead 98% of the bent plastic slabs to be leveled with the advantages of economy, saving energy, convenient and easy operation.

Description

technical field [0001] The invention relates to a method for shaping materials, in particular to a method for restoring flatness to a curved plastic plate, and is especially suitable for processing an acrylic light guide plate. Background technique [0002] The backlight module is mainly used as the light source system of the liquid crystal display. Its working principle is: the light emitted by the point light source or the line light source enters the light guide plate, passes through the bottom surface of the light guide plate with optical structure design and the reflector, so that the light is diffused and emitted. Evenly distributed in the light-emitting area to form a surface light source to meet the optical characteristics of liquid crystal displays. Therefore, the Light Guide Plate is the efficiency center of the light guide of the overall backlight module. Its principle is to use the dot distribution (pattern) on the bottom surface of the light guide plate made of ...

AI Technical Summary

Problems solved by technology

[0005] However, this injection molding method is only maturely applied in the manufacture of small and medium-sized light guide plates

With the emergence of LCD TVs, the demand for large-size light guide plates and backlight modules is increasing. Optical plastic products that are injection molded with precision molds are susceptible to various factors such as melt temperature, mold temperature, filling time, filling speed, and injection pressure. Due to the influence of processing conditions, and because of the high water absorption of acrylic, the product is very easy to bend and deform. The bending deformation of the light guide plate will distort the size, spacing and shape of the microstructure in the light guide plate, and the refractive index, refraction angle and exit of light The position will also change accordingly, resulting in a decrease in the uniformity of the display backlight

[0006] The most common technology used to correct the bending of the light guide plate in the prior art is the annealing process, that is, the plastic product of the light guide plate is placed in an oven, the temperature is precisely controlled, and the slightly deformed and bent light guide plate is baked. The defects of this technology are: 1. On the one hand, because the baking temperature cannot be too high and precise temperature control is required, the equipment is expensive; on the other hand, it consumes a lot of energy

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