Question

blue light lenses

You can write about a blue light lens

The only criteria is that the write up must touch on 3 areas:

1. What is the problem this product (or technique) can solve
2. What are its limitations
3. What are its competing products

This is basically an essay about an optical product that you either are familiar with, or research. No calculations, no maths, and no more than 2 pages.

Answer 1

Blue Light Lenses

Blue Light lenses are basically clear eyeglass lenses with a blue light filter. They have filter in the lenses which can prevent the blue light from passing through.

Blue light of the visible spectrum has the shortest wavelength and highest energy. The cornea and lens of human eye does not block the blue light and it travels all the way through to the retina. Small amount of blue light is not at all harmful. But, the prolonged exposure to blue light increases the risk of macular degeneration. Too much blue light damages the light sensitive cells in retina which can cause permenant loss of vision.

Display of most of the electronic devices available today, like computers, laptops, smartphones, emits considerable mount of blue radiation. Taking into account the considerably large amount of time being spent infront of these devices, especially in dark, there is a high chance of damage to eye. Because blue light scatters easily, they are not focused easily and hence can cause digital strain to eye. It can also lead to insomnia and premature aging of eyes.

So it would be convenient to use a lens with blue light filter to protect your eyes.

Limitations:

i) Not all blue light are harmful. In fact the blue light from sun regulates your Circadian Rhythms, i.e, the natural sleep and wake cycles. So wearing a blue light lens in the day may disturb your Circadian Rhythm.

ii) The blue light filter lenses actually have a yellow tint to it. While they block out all the harmful light, it can cause colour distortion. It casts a yellow tint to the object that you are looking at.

Other alternatives for eye protection include Sunglasses and Leaded glass.

Sunglasses absorb most of the UV radiation and HEV(High Energy Visible) radiation.

Lead shield in the Lead Glasses reduce or completely eliminates the exposure to harmful rays by attenuation of the radiation. Lead acts as a barrier to reduce the X-rays effect by blocking or bouncing particles through a barrier material.