Polarizing film is roughly divided into two types: iodine-type film with superior optical characteristics and dye-type film with superior heat-resistant characteristics. Behind the high durability and high quality of our polarizing films are dyes and adhesives jointly developed with our parent company Nippon Kayaku, a leading dye manufacturer in Japan.
Ordinary light (natural light) travels while oscillating in 360° directions. Polarizing films have a characteristic that allows light oscillations to be shifted from 360° to one desired direction. As shown in the figure on the right, suppose that a polarizing film is a fine filter that has lattices arranged in one specific direction. Light that has oscillations parallel to these lattices can pass through the lattices, but light oscillating in another direction is intercepted. Light can thus be set on a constant and desired direction by allowing it pass through a filter with such a structure.
There are three important optical characteristics of polarizing film: transmittance, polarizing efficiency and hue. LCD luminance and contrast increase as transmittance is brought closer to 50% (theoretical limit value) and polarizing efficiency to 100%.
Polarizing film is made by dyeing film (mainly polyvinyl alcohol (PVA)) or by iodine being adsorbed onto its surface, then stretching and orientating it. This gives the film polarization characteristics that allow only light with a certain oscillation direction to pass through it. Furthermore, in order to secure mechanical strength of the film, backing materials such as a TAC film or a protective film is laminated to it.
Polarizing film is given various kinds of treatment. The film itself is also required to have functions to control reflection, stain and light leakage. Some types of LCDs, touch panels, or organic EL displays also require a product made by laminating a retardation film to the polarizing film. Polatechno is ready to provide our customers with polarizing film most suitable for their respective needs.
Dye-type polarizing film
Iodine-type polarizing film
Bare polarizing film for sunglasses
Circular and elliptical polarizing film