How the Eyes Work

Vector image of an eyeball.

Every morning, we open our eyes and become immersed in a wealth of visual information. The eyes and related brain structures are a complex system that allows us to experience visual information from the surrounding world. It is easy to take clear vision for granted, but even subtle changes in the structure or functioning of the eyes can disrupt our sight. An eye care provider conducts a thorough eye exam to ensure that these components are functioning together well.

Basic Eye Anatomy

The eyeball is not a single, spherical structure as is commonly thought. It consists of a smaller, curved portion called the cornea that attaches to a larger, roughly spherical structure called the sclera (the white of the eye). The eyeball is filled with a jelly-like substance called the vitreous fluid.

Toward the front of the eye are three essential structures: the iris, pupil, and lens. The iris is the colored part of your eye. It can open and close to determine how much light to let in through the pupil, the black hole in the center of your eye. Finally, the lens is a flexible, convex structure that changes shape to direct light rays in different directions within the eye.

At the back of the eyeball is a layer of tissue called the retina. The retina consists of millions of photosensitive cells that react to certain types of light. Cone cells are clustered toward the center of the retina, and react to colors and details in bright light. Rod cells, which are spread toward the periphery of the retina, react to dim lighting conditions.

How the Eyes Facilitate Vision

When light enters the eye through the pupil, it passes through the lens, which changes shape to ensure that the light rays hit the retina. When the light rays reach the back of the eye, it stimulates the rod and cone cells to fire. Cone cells detect fine details and color in the center of your visual field. Rod cells detect edges in peripheral vision and allow us to perceive shapes in dim light.

The rods and cones in your retina convert light energy into electrical signals, which exit the eye through the optic nerve, located just below the center of the retina. The optic nerve carries visual information to the occipital cortex in the very back of your brain, where it is processed to result in a rich visual experience.

If any part of this complex arrangement functions improperly, vision is impaired. Thus, it is essential to receive regular optometry exams to have your eye structures and visual abilities checked.

Contact us to request an appointment today.

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Testimonials

  • We love supporting our local businesses. Dave Nelson is such an asset to our community. He took the extra time needed to be completely thorough with some issues I was having. I love that he looked at my complete health before coming to a conclusion for my needs. We love the customer service from beginning to end. I put complete trust in Lee Ann to pick out some frame choices for me, listening to my wants and needs. She delivered and I am so excited to get them next week. Thank you so much!

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    Show More - C.D.
  • I was extremely pleased with the complete and thorough eye examination I received. Dr. Nelson took a great deal of time explaining his findings so that I understood them. He then laid out a plan for us to follow for the future of my eye health.

    - D.D.
  • I'm impressed with all of the technology. Great service. Thank you!

    - J.O
  • This was the best experience I have had with an eye doctor. I felt like Dr. Nelson actually listened to how my eye sight was affecting my daily routine and properly diagnose my vision correction needs.

    - A.K.
  • I've been a patient of Dr. Nelson for many years and he is absolutely amazing. I am grateful that he uses state-of-the-art tools to measure changes in my eye health. His advice is spot on for caring for my eyes and his prices make it affordable to do so. I highly recommend you schedule your next appointment here

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    Show More - J.B.
  • Exam and discussion of the results were excellent. Dr. Nelson is kind, considerate, and open to any discussion about your eyes. The pictures from the exam were amazing and Dr. Nelson explained everything that was going on with the exam and pictures. Frame and lens selection are outstanding as is the work of the staff in helping to pick out what I wanted. And those sunglasses...oh my...I love them! Great work Dr. Nelson and staff!

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    Show More - T.C.
  • This was the most thorough exam I've ever had and I've had many. Dr. Nelson understood my challenges and I felt confident in his care. Great experience. Thank you

    - L.F.
  • Efficient and courteous service with a sense of belonging to a family. I have had to wear prescription lenses for most of my life. Never, has anyone ever taken the time to explain what happens to our eyes as we age, why and HOW we see floaters (and with the latest technology used in Dr. Nelson's office - to show you these things and so much more.) and other retinal issues if they exist. The latest technology used in Dr. Nelson's office is non-invasive and amazing to literally see the inside of y

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    Show More - P.L.
  • I've seen Dr. Nelson for many years for my eye care before he opened the new practice in Cottage Grove. I appreciate how very thorough he is and how he takes the time to explain any changes in my vision etc. He and his staff are always very kind and friendly and they go the extra mile to help! I liked that Cottage Grove Eye Care was really easy to find...and I like the space and the fact that they have a large selection of cool frames. Would highly recommend it. Nice to have someone you can trus

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    Show More - H.S.
  • I went to Cottage Grove Eye Care for the first time last year and purchased both glasses and contacts. This is the first year that I have consistently worn both the glasses and contacts and didn't experience any issues with either. I always feel much educated about my eye health when I leave in a way that I never was at other eye clinics

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    Show More - E.W.
  • Friendly, professional, very thorough.

    - T.S.

Contact Us

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Monday

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Tuesday

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Wednesday

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Thursday

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7:00 pm

Friday

9:00 am

1:00 pm

Saturday

By Appointment Only

Sunday

Closed

Monday
10:00 am 7:00 pm
Tuesday
9:00 am 5:00 pm
Wednesday
8:00 am 3:00 pm
Thursday
10:00 am 7:00 pm
Friday
9:00 am 1:00 pm
Saturday
By Appointment Only
Sunday
Closed