Polarizer related knowledge
Polarizer is an optical film that provides polarized light for LCD displays
How many types of polarizers are available?
There are two kinds of polarizers, one is iodine-based polarizer and the other is dye-based polarizer
Iodine-based polarizers have high transmittance and high contrast. They not only have a wide range of wavelengths, but also have relatively economical prices, so they have a high market share and are widely used in smart wearable products, calculators, personal computers, etc. , generally used LCD displays also use iodine-based polarizers.
The polarizing properties of dye-based polarizers are worse than that of iodine-based polarizers, but their heat and humidity resistance is very good, so they are widely used in special fields, such as automobiles, ships, aircraft, outdoor measuring instruments, etc., because dye-based polarizers have better durability.
The polarizer is made by repeatedly stretching the resin sheet. The repeated stretching makes the resin only pass light at a specific angle. In order to protect and adhere to the polarizer, there are generally protective film, TAC film, PVA film, TAC film, Induction glue, release film
Additional functions of polarizers
● Reflective/Transflective — Power saving, mostly used in portable electronic products
● Phase difference plate — black and white and color STN
● AG/HC — anti-glare/hardness treatment
● WV — Wide angle of view
● DBEF — Brightness Enhancement Film
● GDA — Diffusion Adhesive – B&W and Color STN
● AR / LR / AS — anti, low reflection / antistatic
Polarizer flow chart
The manufacturing process of polarizer is divided into dyeing, extending, laminating and drying. Among them, dyeing is an important technical key. There are two kinds of iodine-based dyes and dye-based dyes according to different temperature requirements. In addition, the extension orientation control of PVA will also affect the optical properties of the polarizing film. After the polymer film is stretched, the mechanical properties will be reduced and deteriorated. The PVA film is hydrophilic and will deform and shrink quickly after absorbing moisture. Therefore, after the polarizing matrix PVA is stretched, a triacetate (TAC) film should be attached on both sides for protection. After that, it is coated with glue, dried, and coated with a protective film.