Question
Question: The position of the pen seems to be changed when you look at it through your left and right eye with...
The position of the pen seems to be changed when you look at it through your left and right eye with respect to a fixed point on a wall. This effect is called_________.
Solution
This effect increases the distance between the eyes. It is an effect which shows displacement or change in the position of an object viewed from the eye. The left and right points have their own view and line of sights.
Complete answer:
The position of the pen to look through from the left and right eye is a fixed point on a wall. This effect is known as the parallax effect.
The parallax effect is half of the angle between two lines of sights. Also, this effect leads to focus on one point emitting the direction of another eye. The Blind spot is present behind the retina which receives and reacts to incoming light and sends signals to the brain. One part of the retina is however blind and does not provide visual information that is the eye's “blind spot”.
Example- hold an object at eye level about an arm’s length and make sure that it does not cross on the right. Close the right eye and directly cross the left eye. Noticing the dot with another eye. And then focus on the cross, and slowly bring the card close to face to see the dot. Then slowly pinpoint the card to and pro from where this point happens.
Now closing the left eye looks straight to the dot from the right eye. The time taken to observe the dot will disappear and reappear as you bring the card towards the face. The haziness and the time taken by the eye to re-focus on the dot is blind spot.
The optic nerve carrying fibers that messages from eye to brain passes through one spot that is- light sensitive spot and retina of eye. In that blind spot the retina has no receptors so the moment we observe the card close to face and focus on the dot we cannot see the dot.
Note:
The image formation is done from the brain. The image resolving eyes are present in arthropods and chordates. But in higher organisms like-humans have a complex system which collects light from the environment and focuses it through adjustable lenses and converts image to signals which pass through neural pathways and connect through optic nerve.