In our modern technological era, a term we often hear is polarization. But, some of us have less knowledge regarding this technology. Generally, a polarizer is a filter system in the optical elements which works to cut the lights off or block the massive beams and make the scene more visible. The filter can turn the undefined light beams polarizations into specific polarizations. In the present time, the photography instruments and LCD technology manufacturers use the polarizer system to build the solution regarding users’ optical techniques. And the physical element which we know as the polarizing converter is called polarizer film.
We can experience two types of polarizer films around our surroundings; one is the linear polarizer, and another is the circular polarizer. Before we use a linear polarizer film, we must know some basic or prime concepts about it.
The object linear polarizer has two classes.
a. Absorptive Polarizer
In this absorbent polarizing system, the film’s use reduces the unexpected polarizations by absorbing the process. If we discuss broadly, the specific types of crystal named Tourmaline are responsible for creating the effects that the crystal optics describes. Eventually, the result views the dichroism by absorbing the light or polarizing it in a particular direction.
The instrument which works to filter the light waves is called Polaroid, and the vital element of this Polaroid is microscopic herapathite crystals. This polarizer is more affordable than any other polarizing film, and the durability is relatively high. Hence, it has become a common type of polarizer to use, and the general purposes of use are sunglasses, photography instrument’s filters, LCD, etc.
b. Beam-Splitting Polarizer
The name beam-splitting came from the linear polarizer’s working method, and the operational strategy is the polarizer splits the beams from the incident into two particular beams. And one of the output beams goes through the polarization filter forms the polarized beam. Another beam remains mixed with polarization states. This beam-splitting linear polarizer does not act like the absorptive polarizer; it does not require to absorb the lights. Hence, this quality made this polarization system useable to work with beams of high intensity. The brightest example is laser light.
Till now, the description was to understand the primary beam-splitting polarizer. And there are four ways to polarize the beams in this method.
1. Through the Fresnel Reflection
The Fresnel reflection refers to the lights’ polarization through two transparent interfaces at an angle, and the review is different for the polarized beams. We all can design this polarization by keeping crystal clear the glass plates at Brewster’s rise on the beam’s way.
2. Birefringent Polarization
Quartz, calcite, and similar crystal elements can polarize the beams in this birefringent method. Here, the light beam goes through the crystal surface and splits into two ways or rays after polarization by refraction process. And both of the rays will be taking two completely different states.
3. Thin Film Polarization
The thin film polarization method starts with a glass substrate with a unique optical coat to polarize the light beams. The film with the interference effects works to direct the beams as a beam splitter. Generally, there are two ways to use the substrate. One the substrate can be a plate, and the other one is a wedge.
4. Wire-Grid Polarizer
Wire-grid polarizer is the simplest possible linear polarizer. On a plane surface, there many metallic wires, and all of these maintain a parallel distance. This polarizer reflects the non-transmitted polarization, and by this process, it splits the beams.
These were the basic concepts regarding the linear polarizer and polarizing systems. All of the aspects have more important details to learn.