It is often said ‘The eyes are the window to the soul’. Today, from young children to teenagers to adults, almost everyone around us has a barrier between their eyes and the vivid and vast world around them – concave lenses. Glasses and contact lenses have become an inherent part towards protecting our vision. While some parents lament their children having glasses as a result of their unyielding desire for screen time, others boast of their children being studious and bookworms. But the question arises: why has there been an exponential rise in the need for glasses in our society? It is estimated that by 2050, fifty per cent of the population will have myopia.

First, let us understand how we see images in the first place. Rays of light pass through the cornea, which is the front clear layer of the eye. The cornea is dome-shaped and bends light to focus it. The light then enters through the pupil. The iris, the coloured part of the eye, controls how much light enters our eyes. The lens focuses the light on the retina, and photoreceptors turn the rays into electric signals. These electric signals travel through the optic nerve to the brain, which helps us perceive the images that we see. Myopia (nearsightedness) is a condition in which individuals face difficulty seeing distant objects and perceive them as blurry. If the cornea of our eye is too steeply curved or the eye is longer from the front to the back than normal, this unusual shape causes light to be focused in front of the retina instead of on the retina- thus leading to nearsightedness.

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Lamarck stated that organisms alter their behaviour in response to environmental changes, and this changed behaviour modifies their organs, and their offspring inherit such ‘improved’ traits. Charles Darwin’s natural selection talks about the survival of the fittest and their offspring being favoured for reproduction and survival. The truth is myopia is caused by both of these factors to a certain extent. Our lifestyle today is different from what it used to be. Our careers require long hours of eye strain in front of the computer. Children play games on their mobile phones instead of playing outside. The smaller the distance between the object and the lens, the more strain it causes on our eyes. The lack of outdoor exposure, pollution, environmental changes and long hours of blue light have a significant role in the rise of myopia among the youth. The highly demanding academic curriculum and long hours of reading and learning strain the eyes of students.

Our ancestors were hunters and farmers. They had keen eyes to protect themselves and hunt prey. Many eye diseases and defects went undetected in those days as well. In urbanised society, there is no stigma regarding favouring people with good vision, although visual impairments and medical treatments are widely available. Genetics is a major factor contributing to the rise in myopia. Children of myopic parents are more likely to be inflicted by it between ages nine to 16. Asians tend to be myopic more than other races due to unknown environmental and genetic factors and also the cultural emphasis on academics and studying.

Concave lenses correct myopia by being thin at the centre and thick at the edge. It diverges light rays entering the eye so they focus further back, landing directly on the retina instead of in front of it. Hence, they are used in glasses. Eating a balanced diet, avoiding prolonged outdoor exposure and wearing protective eyewear can protect our eyes from damage. We should take preventive measures to protect our eyes and safeguard them from diseases for a brighter future.