Stereoscopic Vision: The Mechanism of 3D Vision
Stereopsis is a process of visual perception in which an in-depth sense of sight creates different perspectives of received information by the horizontal separation of two eyes. This can also be termed as the binocular disparity in animals and retinal disparity in humans.
Stereoscopic vision signifies the three-dimensional visual ability of humans with their two eyes. A single eye creates a two-dimensional image of objects. However, the brain merges these two-dimensional images and interprets their difference. This causes the direct effect of three-dimensional or 3D vision through stereoscopic vision quality in humans.
Meaning of Stereoscopic Vision
In the Greek language, stereo means solid, and scopic means examining or looking. In stereoscopic meaning, the first prefix stereo refers to the ability to operate over multiple dimensions. For instance, the sound coming from multiple speakers is known as the stereo sound that can emulate the natural sound of the surrounding environment, the 3D world. Similarly, this mechanism also applies to stereoscopic vision meaning.
The most important condition of viewing the same object differently is that both the eyes need to be unimpaired as well as synchronised in their movements. This movement helps humans to understand the distance and the ability to achieve the perception of depth in true sense.
Due to retinal disparity, each human eye views slightly different images of a similar object. This helps the brain to interpret these images without physical movements. In this process, the brain first complements the obtained matches and then calculates the difference between these two images.
Even though marginal disparity occurs, the accuracy level of the final image is attainable in regards to depth perception.
Mechanism of Converting 2D Vision into 3D Vision
The human eyes see 2D images separately by each of them and that provide information on height and length. However, the information on the third dimension, width, of the objects can be guessed by foreshortening.
In this process, both the height and length of an object can be shortened because of the perspective. While seeing, the brain instantly and constantly provides information about the width subconsciously. The mechanism behind a 3D vision can be explained by the following.
By holding an object close enough to the face and focusing on the distant objects, two separated and slightly transparent images can be formed. Now, exactly, this happens when the brain creates 3D images.
Human Stereoscopic Vision
Each human eye captures a 2D image and thus, transfers two versions of an image to the brain. Human eyes have an evolved sense of vision that helps the brain to interpret exact synchronisation. Due to the ability of human eyes which possess foveas, felines, primates, and frontal vision, this accurate synchronisation happens.
The distance between two human eyes is about 2 inches. Thus, this retinal disparity helps the brain to process and assess a sense of distance. The brain utilises all these spatial information and brings about precise depth information as stereoscopic vision.
Animal Stereoscopic Vision
Animals can simultaneously interpret the depth information of images by various spatial locus. Thus, they have binocular vision. In some animals, the positions of the eye are in different directions. This quality provides the largest field of vision.
Some animals have forward-facing eyes positioned in the frontal part of their head. These animals can fix their vision on one object or can move their eyes independently. Many aerial animals are blessed with a 360-degree vision field.
The binocular disparity sends different images in the brain and helps it to bring out the stereoscopic vision.
Advantages of Stereoscopic Vision
- With the help of stereoscopic vision, humans can manage to handle small objects.
- It helps to reciprocate threats and react accordingly.
- Provides a deep sense of perception.
- It helps to achieve accuracy in various profiles like the manufacturing industry.
Other than the stereoscopic vision process, humans also use a stereogram mechanism for 3D vision. Cross-eye and parallel viewing are the two methods that bring about a stereogram.
FAQ (Frequently Asked Questions)
- What is a Stereoscopic Vision?
Ans. Stereoscopic vision is a 3D vision created by merging two slightly different images captured by two eyes.
- Why is Stereoscopic Vision Important?
Ans. Stereoscopic vision helps to improve the accuracy of depth perception. Nowadays, for animals, this vision helps them to collect food or defend themselves. However, humans now use stereoscopic vision for artistic purposes.
- What is the Cause of Stereoscopic Vision in Humans?
Ans. Tapetum lucidum between the retina and choroid is the reason for stereoscopic vision in humans.