Parallel Polarization: Several Facts And FAQs

In this article on parallel polarization, we will study several facts and concepts.

In general, polarization is a phenomenon that occurs by stopping the movement of waves that are traveling in a plane, and parallel polarization signifies the parallel direction along which the electric vector moves and propagate to the wave axis. It shows that polarized waves move in a transverse path.

Let’s navigate through the article to know the different insights of parallel polarization.

What is parallel polarization?

When a light beam falls on any matter, the specific process occurs due to polarization. Depending on the types of polarized waves, it is classified widely into parallel and perpendicular polarization.

Parallel polarization occurs when the electric field vector of the wave is parallelly aligned to the plane on which interactions occur. The other component, the magnetic vector, will be perpendicular. Parallel polarization is also known by another name called P-polarized light. It is even transverse.

To concentrate on the different definitions of parallel polarization.

Parallel polarization of light

The term parallel can be referred to as the light rays moving straight along the parallel path in a plane.

The P-polarized light contains a unique characteristic nature of transverse waves and makes its electric vectors move in a parallel path when the interactions between light and matter occur. It considers the plane of incidence and leads to polarized waves.

parallel polarization

To know how a parallel polarization is defined in terms of the wave.

Parallel polarization of wave

Light contains many properties; one of the main characteristics is its dual nature; it can act as a particle and even a wave. Now let us know the parallel polarization of a wave.

The electric and magnetic waves have two types that are transverse and longitudinal. When a transverse electric vector of a light ray is stopped in a plane by certain filters considering the axis of wave propagation, at this point, the waves get polarized and start to vibrate, which is generally termed parallelly polarized wave.

parallel polarization

It was about parallel polarization of wave, and next, let’s know one of the bases of the critical law of polarization called Brewster’s law.

Why Brewster angle occurs for parallel polarization?

Brewster’s angle is, in general, referred to as the angle at which polarization occurs or polarized angle.

Brewster’s angles for a parallel polarization signify that the electric field vectors of light component that gets reflected from a plane at Brewster’s angle are polarized and will travel parallel.

Another consequence is that when light strikes the plane at a polarizing angle, it gets reflected that contains no electric component parallel to the refracted light; it is due to the process that electrons present in atoms cannot oscillate in that path.

At Brewster’s angle, both reflected and refracted will be placed normal to each other.

Transmission coefficient parallel polarization

There is a difference in the meaning of reflected and transmitted rays; when seen in optics, both are entirely different.

In reflection, the rays get reflected within the boundary, whereas the electric and magnetic waves pass through a surface in transmission.


The term transmission coefficient for parallel polarization refers to the ratio of how much a light ray gets transmitted to the intensity of the light that gets incident, and it is measured on a parallel plane.

It’s time to focus on Fresnel’s equations for parallel polarization.

Fresnel equations parallel polarization

The general Fresnel’s equation of light defines the ratio of the electric component vector of the reflected ray to the electric component vector of the incident ray. The same applies to transmitted and incident rays.

Fresnel’s equation for parallel polarization happens through the incidence of the electric component of vector a plane surface. Here the other component that is magnetic will be normal to the same surface.

The equation for Fresnel’s parallel polarization is given below,

parallel polarization

To study the concept of the parallel polarization reflection coefficient.

Parallel polarization reflection coefficient

The reflection coefficient of light in the optics is defined as the attribute used to measure the number of waves that get reflected by a barrier that causes discontinuity in the transmission surface.

The parallel polarization reflection coefficient is defined as the ratio of the maximum path that a wave moves from a point is calculated from the equilibrium point of the reflected wave to the initial ray.


If we consider Fresnel’s equation, if we measure a similar reflection coefficient at 90°, it will result in zero.

Parallel polarization oblique incidence

The term oblique for a light ray tells that it falls on any matter in a slightly bent form, and the oblique incidence refers to the incident light that strikes the surface at an oblique angle, or we can say that it is not perpendicular to the surface.

The parallel polarization oblique incidence is when an incident light falls obliquely (not at 90) on a plane. The electric component of wave vectors moves parallel to the propagation axis.

Therefore, the parallel polarization oblique incidence occurs at an oblique angle leading to parallel polarized waves.

Polarization parallel plate capacitor

A parallel plate capacitor is a combination of two charged plates that are placed parallelly to each other, connecting a battery; it is constructed in this way to attain an electric field between them.

Polarization in a parallel plate capacitor occurs when any material made up of dielectric is placed between the plates; the electric field polarizes the dielectric. When you immerse the material between the plates, its constant value increases, making it polarized.

These were some concepts related to the parallel polarization of light.

To know more: Properties of Refraction

Frequently Asked Questions on Parallel Polarization | FAQs

What is the typical difference between parallel and perpendicularly polarized waves?

The common difference between parallel and perpendicularly polarized waves lies in their direction of travel.

In the s-polarized waves, also known as perpendicular polarization, the electric vector of these waves moves in a direction that will be at 90° to the wave axis. In contrast, P-Polarized that is considered parallel polarized waves, moves in a straight, parallel path to the wave axis.

What is the meaning of wave polarization?

Polarization is a phenomenon that is usually seen in the waves. With specific processes, the light gets blocked through some filters producing polarized waves.

It is usually considered a property that applies to the waves, which produce the bodies vibrating and oscillating. It has two classifications based on the types of waves.

What phenomenon results in the polarization of light?

Polarization of light is associated with waves that contain electric and magnetic components.

When any light interacts with a body or material, some amount of light suffers restriction on a plane resulting in the production of polarized light.

What is the cause of the Brewster angle?

The cause for Brewster’s angle is the reflection of a polarized light ray.

It is also considered as an incident angle. Brewster’s angle leads to the formation of angles between both reflected and refracted rays. The light ray strikes the surface in a way making the incident ray fall at 90°

What is Brewster’s angle in the field of electromagnetic theory?

Brewster angle is defined in terms of electric and magnetic components in electromagnetic theory.

It is defined as the angle of unpolarized electromagnetic wave that is made to an incident on a plane on average, which results in polarized waves. The initial electromagnetic wave consists of the same amount of parallel and perpendicular polarized waves.

Why does the parallel reflection of polarized light not occur at Brewster’s angle?

Only one light component gets polarized at Brewster angle, i.e., perpendicular polarized wave

What are the main conditions for Brewster’s and critical angle to occur?

The critical angle refers to that angle formed beyond the standard angle.

The primary condition for an angle to be Brewster’s and critical are the ray that gets reflected or refracted must strike the surface at 90 from the last ray, and it will be less polarized. The critical aspect is that critical and Brewster angles are necessary to measure the refractive index.

Why is the coefficient of transmission will be greater than 1?

We know that the transmission coefficient of polarized light will measure the ratios of amplitudes of polarized waves.

The transmission coefficient will be greater than one when the ratios of the two aspects undertaken are the same. When the value is more, it results in different impedances and amplitudes.

What will be the effect of polarization on the capacitance of a parallel plate capacitor?

The capacitance on the parallel plate capacitor increases due to polarization.

When any material made up of dielectric is inserted in the middle of two plates and a battery, and due to the previously generated electric field, the object gets polarized. It leads to the increase in capacitance of the plates due to the attraction between an accumulated layer of unlike charges.

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