Iris Function


human-eye-structure1The eyes are about the most vital part of our bodies & life. They are the tools that we use to visualize everything so that we can function. Through them we see everything in full light and color. As it may sound the eyes are very complicated instruments. Each individual component of the eye plays an important role in helping us to see. The iris of the eye is on of the key parts of the eye that works to help us to see the world. But what is the iris function? How does it play such an important role in helping  our eyes to perform their job of vision?


Function of the Iris: The Breakdown

The iris of the eye is the part of the eye that is located in between the cornea and lens. It resides at the bottom part of the pupil right underneath it. It is shaped like a small disc and contains fibers & tissues that connect together.

Iris Function: Eye Color Definition

A person’s eye color is indicative by the iris. The more the pigment the iris has, the more dark the eye color will be.The iris is unique as each individual will have various textures and patterns in their iris. This works much like the way that a finger print is unique between each person.The iris function also works to provide a barrier that sits between the anterior chamber (inside lens) and posterior chamber(outside lens)- it is the one the eye part that divides them .

Iris Function: Controls Light

Another iris function is that it controls light that is visualized and see by the human eye. It can filter it. It does this in order to protect the eye as well.The pupil is located in the very center of the iris.

It is a small, circular opening built with tissues and muscles that work to dilate (open, expand) or contract (shrink down.) When the pupil is dilated it allows more light to be absorbed by the retina. When is is contracted or small, the pupil will not be able to absorb as much light. This function helps to safe-guard the retina from being damaged.

Iris Function: Problems That Can Occur

bigeyeThere are certain conditions and functions that can impact the iris function negatively. These things can range from eye accidents and trauma, to congenital anomalies that a person can have when they are born. Some of these problems can cause the iris function to not work properly.

Problems with the iris can cause too much light to enter the retina that results in shadows, dark spots, and double vision. It can also cause blurred vision and hinder the ability for a person to be able to focus on anything they look at or try to visualize.

Additionally, there are parts of the eye (retina & urea) that are located around the iris that can also become damaged or problematic.

When the iris or local components near the iris are negatively impacted, the following symptoms can arise:

  1. Iris Colomba: Iris coloboma is usually brought about by a direct trauma or a physical defect. This can make it appear as if the eye has an odd shape and it also causes a hole in the iris itself.
  2. Burns, Pokes, Damage to Eye from Trauma:  Burns, pokes, and other traumas can impact the iris in a negative eay. The eye ca n be pierced by an object or impacted by a burn.
  3. Inflamed Iris: The iris can become irritated and inflamed for any reason. When this happens a person will experience sensitivity to light and also have blurry vision.
  4. Aniridia: Aniridia is not very common. But occasionally it does happen. It is where the iris for some reason is not developed fully. It is a disease of the iris that occurs while a baby is in the womb.
  5. Indocyclitis: Indocyclitis is a condition that is pretty common. It is a condition that impacts the ciliary body and the iris at the same time. When treated in a timely manner, this condition can be cured with a course of antibiotics, however if not caught early this can prove lethal to one’s sight and even cause them to be blind.

Iris Function: Other Components of the Eye


The sclera is the white part of the eye. It helps to protect the inner eye parts and also serves as a foundation for them.

Aqueous and Vitreous Humor

The Aqueous humor is a part of the eye that holds water. It consists of two main parts the anterior and posterior chamber. Between these chambers lies the iris. The Vitreous humor is made of a gel. It placed in the very back of the eye. It provides the entire eye its ovular-like shape


The dome part of the eye that covers it is known as the cornea. It functions to protect the eye from damage, But it is transparent so we are still able to see through it. The cornea is made-up of several layers that can regenerate. It is also where the light that enters the eye is put into focus.

Lacrimal and Conjunctiva Glands

The Lacrimal and conjunctive glands are the glands that actually produce moisture for the eye by way of tears and also mucus linings that keep the eyes moist and healthy,.


The lens is a clear component of the eye that’s placement lies right beneath the pupil. It is the part of the eye that works with the ciliary body muscles that change shape and also can help give focus to your vision


The retina is located at the very inner part of the eye. It is what transmits the visions to our brains that are comprehended as images. It consists of a fovea and a macula which each have responsibilities to detailing our perceptions and our visions.