Manufacturing process of light guide plate

It is a process of filling melted forming materials into a closed mold under high pressure, which requires the light guide plate and microstructure to be completed synchronously in injection molding. At the same time, the mold must be made quite sturdy, so the mold price is also quite expensive. Therefore, it must be produced in large quantities to offset the high mold cost. Single sided microstructure array light guide plates are generally produced using injection molding technology, and their bottom texture structure can be in the shape of micro lenses, micro spheres, or tetrahedral prisms.
photolithography
Photolithography technology is the process of coating a corrosion-resistant photoresist layer on a flat silicon wafer, and then allowing strong light to pass through the lithography plate. Selective exposure is performed on the lithography plate based on the specific layer pattern information produced. Next, the developed photoresist is removed, leaving a thin film with micro patterned structures on the surface of the silicon wafer. The surface roughness of the light guide plate made by photolithography is poor, and the loss of light energy is relatively large.
doping
During the injection molding of the light guide plate, a transparent particle material with scattering function is directly injected into the inside of the light guide plate. By adjusting the concentration of the transparent particles reasonably, effective control of the light output is achieved, ultimately achieving high uniformity of the light output. Due to the difficulty in precise control of the doping process, injection molding is suitable for producing small and medium-sized light guide plates. However, for large-sized light guide plates, uneven light output may occur.
laser engraving
The laser engraving production method is to use a computer to strictly control the energy and position of the laser head according to the program requirements, and use gasification to carve a microstructure array with a certain size on the back of the light guide plate. This method can accurately control the depth of the scattering structure, but its efficiency is low and not suitable for mass production.
sandblasting
Use sandblasting to create molds with rough distribution surfaces, and transfer the rough distribution on the mold to the light guide plate during injection molding. The more rough the surface, the stronger the scattering ability. By adjusting the surface roughness distribution reasonably, the light on the light emitting surface can be evenly distributed.